// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Linux Socket Filter - Kernel level socket filtering
 *
 * Based on the design of the Berkeley Packet Filter. The new
 * internal format has been designed by PLUMgrid:
 *
 *      Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com
 *
 * Authors:
 *
 *      Jay Schulist <jschlst@samba.org>
 *      Alexei Starovoitov <ast@plumgrid.com>
 *      Daniel Borkmann <dborkman@redhat.com>
 *
 * Andi Kleen - Fix a few bad bugs and races.
 * Kris Katterjohn - Added many additional checks in bpf_check_classic()
 */

#include <linux/atomic.h>
#include <linux/bpf_verifier.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/fcntl.h>
#include <linux/socket.h>
#include <linux/sock_diag.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/if_packet.h>
#include <linux/if_arp.h>
#include <linux/gfp.h>
#include <net/inet_common.h>
#include <net/ip.h>
#include <net/protocol.h>
#include <net/netlink.h>
#include <linux/skbuff.h>
#include <linux/skmsg.h>
#include <net/sock.h>
#include <net/flow_dissector.h>
#include <linux/errno.h>
#include <linux/timer.h>
#include <linux/uaccess.h>
#include <linux/unaligned.h>
#include <linux/filter.h>
#include <linux/ratelimit.h>
#include <linux/seccomp.h>
#include <linux/if_vlan.h>
#include <linux/bpf.h>
#include <linux/btf.h>
#include <net/sch_generic.h>
#include <net/cls_cgroup.h>
#include <net/dst_metadata.h>
#include <net/dst.h>
#include <net/sock_reuseport.h>
#include <net/busy_poll.h>
#include <net/tcp.h>
#include <net/xfrm.h>
#include <net/udp.h>
#include <linux/bpf_trace.h>
#include <net/xdp_sock.h>
#include <linux/inetdevice.h>
#include <net/inet_hashtables.h>
#include <net/inet6_hashtables.h>
#include <net/ip_fib.h>
#include <net/nexthop.h>
#include <net/flow.h>
#include <net/arp.h>
#include <net/ipv6.h>
#include <net/net_namespace.h>
#include <linux/seg6_local.h>
#include <net/seg6.h>
#include <net/seg6_local.h>
#include <net/lwtunnel.h>
#include <net/bpf_sk_storage.h>
#include <net/transp_v6.h>
#include <linux/btf_ids.h>
#include <net/tls.h>
#include <net/xdp.h>
#include <net/mptcp.h>
#include <net/netfilter/nf_conntrack_bpf.h>
#include <net/netkit.h>
#include <linux/un.h>
#include <net/xdp_sock_drv.h>
#include <net/inet_dscp.h>

#include "dev.h"

/* Keep the struct bpf_fib_lookup small so that it fits into a cacheline */
static_assert(sizeof(struct bpf_fib_lookup) == 64, "struct bpf_fib_lookup size check");

static const struct bpf_func_proto *
bpf_sk_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog);

int copy_bpf_fprog_from_user(struct sock_fprog *dst, sockptr_t src, int len)
{
        if (in_compat_syscall()) {
                struct compat_sock_fprog f32;

                if (len != sizeof(f32))
                        return -EINVAL;
                if (copy_from_sockptr(&f32, src, sizeof(f32)))
                        return -EFAULT;
                memset(dst, 0, sizeof(*dst));
                dst->len = f32.len;
                dst->filter = compat_ptr(f32.filter);
        } else {
                if (len != sizeof(*dst))
                        return -EINVAL;
                if (copy_from_sockptr(dst, src, sizeof(*dst)))
                        return -EFAULT;
        }

        return 0;
}
EXPORT_SYMBOL_GPL(copy_bpf_fprog_from_user);

/**
 *      sk_filter_trim_cap - run a packet through a socket filter
 *      @sk: sock associated with &sk_buff
 *      @skb: buffer to filter
 *      @cap: limit on how short the eBPF program may trim the packet
 *
 * Run the eBPF program and then cut skb->data to correct size returned by
 * the program. If pkt_len is 0 we toss packet. If skb->len is smaller
 * than pkt_len we keep whole skb->data. This is the socket level
 * wrapper to bpf_prog_run. It returns 0 if the packet should
 * be accepted or a drop_reason if the packet should be tossed.
 *
 */
enum skb_drop_reason
sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap)
{
        enum skb_drop_reason drop_reason;
        struct sk_filter *filter;
        int err;

        /*
         * If the skb was allocated from pfmemalloc reserves, only
         * allow SOCK_MEMALLOC sockets to use it as this socket is
         * helping free memory
         */
        if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) {
                NET_INC_STATS(sock_net(sk), LINUX_MIB_PFMEMALLOCDROP);
                return SKB_DROP_REASON_PFMEMALLOC;
        }
        err = BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb);
        if (err)
                return SKB_DROP_REASON_SOCKET_FILTER;

        err = security_sock_rcv_skb(sk, skb);
        if (err)
                return SKB_DROP_REASON_SECURITY_HOOK;

        drop_reason = 0;
        rcu_read_lock();
        filter = rcu_dereference(sk->sk_filter);
        if (filter) {
                struct sock *save_sk = skb->sk;
                unsigned int pkt_len;

                skb->sk = sk;
                pkt_len = bpf_prog_run_save_cb(filter->prog, skb);
                skb->sk = save_sk;
                err = pkt_len ? pskb_trim(skb, max(cap, pkt_len)) : -EPERM;
                if (err)
                        drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
        }
        rcu_read_unlock();

        return drop_reason;
}
EXPORT_SYMBOL(sk_filter_trim_cap);

BPF_CALL_1(bpf_skb_get_pay_offset, struct sk_buff *, skb)
{
        return skb_get_poff(skb);
}

BPF_CALL_3(bpf_skb_get_nlattr, struct sk_buff *, skb, u32, a, u32, x)
{
        struct nlattr *nla;

        if (skb_is_nonlinear(skb))
                return 0;

        if (skb->len < sizeof(struct nlattr))
                return 0;

        if (a > skb->len - sizeof(struct nlattr))
                return 0;

        nla = nla_find((struct nlattr *) &skb->data[a], skb->len - a, x);
        if (nla)
                return (void *) nla - (void *) skb->data;

        return 0;
}

BPF_CALL_3(bpf_skb_get_nlattr_nest, struct sk_buff *, skb, u32, a, u32, x)
{
        struct nlattr *nla;

        if (skb_is_nonlinear(skb))
                return 0;

        if (skb->len < sizeof(struct nlattr))
                return 0;

        if (a > skb->len - sizeof(struct nlattr))
                return 0;

        nla = (struct nlattr *) &skb->data[a];
        if (!nla_ok(nla, skb->len - a))
                return 0;

        nla = nla_find_nested(nla, x);
        if (nla)
                return (void *) nla - (void *) skb->data;

        return 0;
}

static int bpf_skb_load_helper_convert_offset(const struct sk_buff *skb, int offset)
{
        if (likely(offset >= 0))
                return offset;

        if (offset >= SKF_NET_OFF)
                return offset - SKF_NET_OFF + skb_network_offset(skb);

        if (offset >= SKF_LL_OFF && skb_mac_header_was_set(skb))
                return offset - SKF_LL_OFF + skb_mac_offset(skb);

        return INT_MIN;
}

BPF_CALL_4(bpf_skb_load_helper_8, const struct sk_buff *, skb, const void *,
           data, int, headlen, int, offset)
{
        u8 tmp;
        const int len = sizeof(tmp);

        offset = bpf_skb_load_helper_convert_offset(skb, offset);
        if (offset == INT_MIN)
                return -EFAULT;

        if (headlen - offset >= len)
                return *(u8 *)(data + offset);
        if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
                return tmp;
        else
                return -EFAULT;
}

BPF_CALL_2(bpf_skb_load_helper_8_no_cache, const struct sk_buff *, skb,
           int, offset)
{
        return ____bpf_skb_load_helper_8(skb, skb->data, skb->len - skb->data_len,
                                         offset);
}

BPF_CALL_4(bpf_skb_load_helper_16, const struct sk_buff *, skb, const void *,
           data, int, headlen, int, offset)
{
        __be16 tmp;
        const int len = sizeof(tmp);

        offset = bpf_skb_load_helper_convert_offset(skb, offset);
        if (offset == INT_MIN)
                return -EFAULT;

        if (headlen - offset >= len)
                return get_unaligned_be16(data + offset);
        if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
                return be16_to_cpu(tmp);
        else
                return -EFAULT;
}

BPF_CALL_2(bpf_skb_load_helper_16_no_cache, const struct sk_buff *, skb,
           int, offset)
{
        return ____bpf_skb_load_helper_16(skb, skb->data, skb->len - skb->data_len,
                                          offset);
}

BPF_CALL_4(bpf_skb_load_helper_32, const struct sk_buff *, skb, const void *,
           data, int, headlen, int, offset)
{
        __be32 tmp;
        const int len = sizeof(tmp);

        offset = bpf_skb_load_helper_convert_offset(skb, offset);
        if (offset == INT_MIN)
                return -EFAULT;

        if (headlen - offset >= len)
                return get_unaligned_be32(data + offset);
        if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
                return be32_to_cpu(tmp);
        else
                return -EFAULT;
}

BPF_CALL_2(bpf_skb_load_helper_32_no_cache, const struct sk_buff *, skb,
           int, offset)
{
        return ____bpf_skb_load_helper_32(skb, skb->data, skb->len - skb->data_len,
                                          offset);
}

static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg,
                              struct bpf_insn *insn_buf)
{
        struct bpf_insn *insn = insn_buf;

        switch (skb_field) {
        case SKF_AD_MARK:
                BUILD_BUG_ON(sizeof_field(struct sk_buff, mark) != 4);

                *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
                                      offsetof(struct sk_buff, mark));
                break;

        case SKF_AD_PKTTYPE:
                *insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_TYPE_OFFSET);
                *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, PKT_TYPE_MAX);
#ifdef __BIG_ENDIAN_BITFIELD
                *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 5);
#endif
                break;

        case SKF_AD_QUEUE:
                BUILD_BUG_ON(sizeof_field(struct sk_buff, queue_mapping) != 2);

                *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
                                      offsetof(struct sk_buff, queue_mapping));
                break;

        case SKF_AD_VLAN_TAG:
                BUILD_BUG_ON(sizeof_field(struct sk_buff, vlan_tci) != 2);

                /* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
                *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
                                      offsetof(struct sk_buff, vlan_tci));
                break;
        case SKF_AD_VLAN_TAG_PRESENT:
                BUILD_BUG_ON(sizeof_field(struct sk_buff, vlan_all) != 4);
                *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
                                      offsetof(struct sk_buff, vlan_all));
                *insn++ = BPF_JMP_IMM(BPF_JEQ, dst_reg, 0, 1);
                *insn++ = BPF_ALU32_IMM(BPF_MOV, dst_reg, 1);
                break;
        }

        return insn - insn_buf;
}

static bool convert_bpf_extensions(struct sock_filter *fp,
                                   struct bpf_insn **insnp)
{
        struct bpf_insn *insn = *insnp;
        u32 cnt;

        switch (fp->k) {
        case SKF_AD_OFF + SKF_AD_PROTOCOL:
                BUILD_BUG_ON(sizeof_field(struct sk_buff, protocol) != 2);

                /* A = *(u16 *) (CTX + offsetof(protocol)) */
                *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
                                      offsetof(struct sk_buff, protocol));
                /* A = ntohs(A) [emitting a nop or swap16] */
                *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
                break;

        case SKF_AD_OFF + SKF_AD_PKTTYPE:
                cnt = convert_skb_access(SKF_AD_PKTTYPE, BPF_REG_A, BPF_REG_CTX, insn);
                insn += cnt - 1;
                break;

        case SKF_AD_OFF + SKF_AD_IFINDEX:
        case SKF_AD_OFF + SKF_AD_HATYPE:
                BUILD_BUG_ON(sizeof_field(struct net_device, ifindex) != 4);
                BUILD_BUG_ON(sizeof_field(struct net_device, type) != 2);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
                                      BPF_REG_TMP, BPF_REG_CTX,
                                      offsetof(struct sk_buff, dev));
                /* if (tmp != 0) goto pc + 1 */
                *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_TMP, 0, 1);
                *insn++ = BPF_EXIT_INSN();
                if (fp->k == SKF_AD_OFF + SKF_AD_IFINDEX)
                        *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_TMP,
                                            offsetof(struct net_device, ifindex));
                else
                        *insn = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_TMP,
                                            offsetof(struct net_device, type));
                break;

        case SKF_AD_OFF + SKF_AD_MARK:
                cnt = convert_skb_access(SKF_AD_MARK, BPF_REG_A, BPF_REG_CTX, insn);
                insn += cnt - 1;
                break;

        case SKF_AD_OFF + SKF_AD_RXHASH:
                BUILD_BUG_ON(sizeof_field(struct sk_buff, hash) != 4);

                *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX,
                                    offsetof(struct sk_buff, hash));
                break;

        case SKF_AD_OFF + SKF_AD_QUEUE:
                cnt = convert_skb_access(SKF_AD_QUEUE, BPF_REG_A, BPF_REG_CTX, insn);
                insn += cnt - 1;
                break;

        case SKF_AD_OFF + SKF_AD_VLAN_TAG:
                cnt = convert_skb_access(SKF_AD_VLAN_TAG,
                                         BPF_REG_A, BPF_REG_CTX, insn);
                insn += cnt - 1;
                break;

        case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT:
                cnt = convert_skb_access(SKF_AD_VLAN_TAG_PRESENT,
                                         BPF_REG_A, BPF_REG_CTX, insn);
                insn += cnt - 1;
                break;

        case SKF_AD_OFF + SKF_AD_VLAN_TPID:
                BUILD_BUG_ON(sizeof_field(struct sk_buff, vlan_proto) != 2);

                /* A = *(u16 *) (CTX + offsetof(vlan_proto)) */
                *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
                                      offsetof(struct sk_buff, vlan_proto));
                /* A = ntohs(A) [emitting a nop or swap16] */
                *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
                break;

        case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
        case SKF_AD_OFF + SKF_AD_NLATTR:
        case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
        case SKF_AD_OFF + SKF_AD_CPU:
        case SKF_AD_OFF + SKF_AD_RANDOM:
                /* arg1 = CTX */
                *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
                /* arg2 = A */
                *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_A);
                /* arg3 = X */
                *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_X);
                /* Emit call(arg1=CTX, arg2=A, arg3=X) */
                switch (fp->k) {
                case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
                        *insn = BPF_EMIT_CALL(bpf_skb_get_pay_offset);
                        break;
                case SKF_AD_OFF + SKF_AD_NLATTR:
                        *insn = BPF_EMIT_CALL(bpf_skb_get_nlattr);
                        break;
                case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
                        *insn = BPF_EMIT_CALL(bpf_skb_get_nlattr_nest);
                        break;
                case SKF_AD_OFF + SKF_AD_CPU:
                        *insn = BPF_EMIT_CALL(bpf_get_raw_cpu_id);
                        break;
                case SKF_AD_OFF + SKF_AD_RANDOM:
                        *insn = BPF_EMIT_CALL(bpf_user_rnd_u32);
                        bpf_user_rnd_init_once();
                        break;
                }
                break;

        case SKF_AD_OFF + SKF_AD_ALU_XOR_X:
                /* A ^= X */
                *insn = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_X);
                break;

        default:
                /* This is just a dummy call to avoid letting the compiler
                 * evict __bpf_call_base() as an optimization. Placed here
                 * where no-one bothers.
                 */
                BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
                return false;
        }

        *insnp = insn;
        return true;
}

static bool convert_bpf_ld_abs(struct sock_filter *fp, struct bpf_insn **insnp)
{
        const bool unaligned_ok = IS_BUILTIN(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS);
        int size = bpf_size_to_bytes(BPF_SIZE(fp->code));
        bool endian = BPF_SIZE(fp->code) == BPF_H ||
                      BPF_SIZE(fp->code) == BPF_W;
        bool indirect = BPF_MODE(fp->code) == BPF_IND;
        const int ip_align = NET_IP_ALIGN;
        struct bpf_insn *insn = *insnp;
        int offset = fp->k;

        if (!indirect &&
            ((unaligned_ok && offset >= 0) ||
             (!unaligned_ok && offset >= 0 &&
              offset + ip_align >= 0 &&
              (offset + ip_align) % size == 0))) {
                bool ldx_off_ok = offset <= S16_MAX;

                *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_H);
                if (offset)
                        *insn++ = BPF_ALU64_IMM(BPF_SUB, BPF_REG_TMP, offset);
                *insn++ = BPF_JMP_IMM(BPF_JSLT, BPF_REG_TMP,
                                      size, 2 + endian + (!ldx_off_ok * 2));
                if (ldx_off_ok) {
                        *insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A,
                                              BPF_REG_D, offset);
                } else {
                        *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_D);
                        *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_TMP, offset);
                        *insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A,
                                              BPF_REG_TMP, 0);
                }
                if (endian)
                        *insn++ = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, size * 8);
                *insn++ = BPF_JMP_A(8);
        }

        *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
        *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_D);
        *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_H);
        if (!indirect) {
                *insn++ = BPF_MOV64_IMM(BPF_REG_ARG4, offset);
        } else {
                *insn++ = BPF_MOV64_REG(BPF_REG_ARG4, BPF_REG_X);
                if (fp->k)
                        *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG4, offset);
        }

        switch (BPF_SIZE(fp->code)) {
        case BPF_B:
                *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8);
                break;
        case BPF_H:
                *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16);
                break;
        case BPF_W:
                *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32);
                break;
        default:
                return false;
        }

        *insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_A, 0, 2);
        *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
        *insn   = BPF_EXIT_INSN();

        *insnp = insn;
        return true;
}

/**
 *      bpf_convert_filter - convert filter program
 *      @prog: the user passed filter program
 *      @len: the length of the user passed filter program
 *      @new_prog: allocated 'struct bpf_prog' or NULL
 *      @new_len: pointer to store length of converted program
 *      @seen_ld_abs: bool whether we've seen ld_abs/ind
 *
 * Remap 'sock_filter' style classic BPF (cBPF) instruction set to 'bpf_insn'
 * style extended BPF (eBPF).
 * Conversion workflow:
 *
 * 1) First pass for calculating the new program length:
 *   bpf_convert_filter(old_prog, old_len, NULL, &new_len, &seen_ld_abs)
 *
 * 2) 2nd pass to remap in two passes: 1st pass finds new
 *    jump offsets, 2nd pass remapping:
 *   bpf_convert_filter(old_prog, old_len, new_prog, &new_len, &seen_ld_abs)
 */
static int bpf_convert_filter(struct sock_filter *prog, int len,
                              struct bpf_prog *new_prog, int *new_len,
                              bool *seen_ld_abs)
{
        int new_flen = 0, pass = 0, target, i, stack_off;
        struct bpf_insn *new_insn, *first_insn = NULL;
        struct sock_filter *fp;
        int *addrs = NULL;
        u8 bpf_src;

        BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK);
        BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG);

        if (len <= 0 || len > BPF_MAXINSNS)
                return -EINVAL;

        if (new_prog) {
                first_insn = new_prog->insnsi;
                addrs = kzalloc_objs(*addrs, len, GFP_KERNEL | __GFP_NOWARN);
                if (!addrs)
                        return -ENOMEM;
        }

do_pass:
        new_insn = first_insn;
        fp = prog;

        /* Classic BPF related prologue emission. */
        if (new_prog) {
                /* Classic BPF expects A and X to be reset first. These need
                 * to be guaranteed to be the first two instructions.
                 */
                *new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
                *new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_X, BPF_REG_X);

                /* All programs must keep CTX in callee saved BPF_REG_CTX.
                 * In eBPF case it's done by the compiler, here we need to
                 * do this ourself. Initial CTX is present in BPF_REG_ARG1.
                 */
                *new_insn++ = BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1);
                if (*seen_ld_abs) {
                        /* For packet access in classic BPF, cache skb->data
                         * in callee-saved BPF R8 and skb->len - skb->data_len
                         * (headlen) in BPF R9. Since classic BPF is read-only
                         * on CTX, we only need to cache it once.
                         */
                        *new_insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
                                                  BPF_REG_D, BPF_REG_CTX,
                                                  offsetof(struct sk_buff, data));
                        *new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_H, BPF_REG_CTX,
                                                  offsetof(struct sk_buff, len));
                        *new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_TMP, BPF_REG_CTX,
                                                  offsetof(struct sk_buff, data_len));
                        *new_insn++ = BPF_ALU32_REG(BPF_SUB, BPF_REG_H, BPF_REG_TMP);
                }
        } else {
                new_insn += 3;
        }

        for (i = 0; i < len; fp++, i++) {
                struct bpf_insn tmp_insns[32] = { };
                struct bpf_insn *insn = tmp_insns;

                if (addrs)
                        addrs[i] = new_insn - first_insn;

                switch (fp->code) {
                /* All arithmetic insns and skb loads map as-is. */
                case BPF_ALU | BPF_ADD | BPF_X:
                case BPF_ALU | BPF_ADD | BPF_K:
                case BPF_ALU | BPF_SUB | BPF_X:
                case BPF_ALU | BPF_SUB | BPF_K:
                case BPF_ALU | BPF_AND | BPF_X:
                case BPF_ALU | BPF_AND | BPF_K:
                case BPF_ALU | BPF_OR | BPF_X:
                case BPF_ALU | BPF_OR | BPF_K:
                case BPF_ALU | BPF_LSH | BPF_X:
                case BPF_ALU | BPF_LSH | BPF_K:
                case BPF_ALU | BPF_RSH | BPF_X:
                case BPF_ALU | BPF_RSH | BPF_K:
                case BPF_ALU | BPF_XOR | BPF_X:
                case BPF_ALU | BPF_XOR | BPF_K:
                case BPF_ALU | BPF_MUL | BPF_X:
                case BPF_ALU | BPF_MUL | BPF_K:
                case BPF_ALU | BPF_DIV | BPF_X:
                case BPF_ALU | BPF_DIV | BPF_K:
                case BPF_ALU | BPF_MOD | BPF_X:
                case BPF_ALU | BPF_MOD | BPF_K:
                case BPF_ALU | BPF_NEG:
                case BPF_LD | BPF_ABS | BPF_W:
                case BPF_LD | BPF_ABS | BPF_H:
                case BPF_LD | BPF_ABS | BPF_B:
                case BPF_LD | BPF_IND | BPF_W:
                case BPF_LD | BPF_IND | BPF_H:
                case BPF_LD | BPF_IND | BPF_B:
                        /* Check for overloaded BPF extension and
                         * directly convert it if found, otherwise
                         * just move on with mapping.
                         */
                        if (BPF_CLASS(fp->code) == BPF_LD &&
                            BPF_MODE(fp->code) == BPF_ABS &&
                            convert_bpf_extensions(fp, &insn))
                                break;
                        if (BPF_CLASS(fp->code) == BPF_LD &&
                            convert_bpf_ld_abs(fp, &insn)) {
                                *seen_ld_abs = true;
                                break;
                        }

                        if (fp->code == (BPF_ALU | BPF_DIV | BPF_X) ||
                            fp->code == (BPF_ALU | BPF_MOD | BPF_X)) {
                                *insn++ = BPF_MOV32_REG(BPF_REG_X, BPF_REG_X);
                                /* Error with exception code on div/mod by 0.
                                 * For cBPF programs, this was always return 0.
                                 */
                                *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_X, 0, 2);
                                *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
                                *insn++ = BPF_EXIT_INSN();
                        }

                        *insn = BPF_RAW_INSN(fp->code, BPF_REG_A, BPF_REG_X, 0, fp->k);
                        break;

                /* Jump transformation cannot use BPF block macros
                 * everywhere as offset calculation and target updates
                 * require a bit more work than the rest, i.e. jump
                 * opcodes map as-is, but offsets need adjustment.
                 */

#define BPF_EMIT_JMP                                                    \
        do {                                                            \
                const s32 off_min = S16_MIN, off_max = S16_MAX;         \
                s32 off;                                                \
                                                                        \
                if (target >= len || target < 0)                        \
                        goto err;                                       \
                off = addrs ? addrs[target] - addrs[i] - 1 : 0;         \
                /* Adjust pc relative offset for 2nd or 3rd insn. */    \
                off -= insn - tmp_insns;                                \
                /* Reject anything not fitting into insn->off. */       \
                if (off < off_min || off > off_max)                     \
                        goto err;                                       \
                insn->off = off;                                        \
        } while (0)

                case BPF_JMP | BPF_JA:
                        target = i + fp->k + 1;
                        insn->code = fp->code;
                        BPF_EMIT_JMP;
                        break;

                case BPF_JMP | BPF_JEQ | BPF_K:
                case BPF_JMP | BPF_JEQ | BPF_X:
                case BPF_JMP | BPF_JSET | BPF_K:
                case BPF_JMP | BPF_JSET | BPF_X:
                case BPF_JMP | BPF_JGT | BPF_K:
                case BPF_JMP | BPF_JGT | BPF_X:
                case BPF_JMP | BPF_JGE | BPF_K:
                case BPF_JMP | BPF_JGE | BPF_X:
                        if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) {
                                /* BPF immediates are signed, zero extend
                                 * immediate into tmp register and use it
                                 * in compare insn.
                                 */
                                *insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k);

                                insn->dst_reg = BPF_REG_A;
                                insn->src_reg = BPF_REG_TMP;
                                bpf_src = BPF_X;
                        } else {
                                insn->dst_reg = BPF_REG_A;
                                insn->imm = fp->k;
                                bpf_src = BPF_SRC(fp->code);
                                insn->src_reg = bpf_src == BPF_X ? BPF_REG_X : 0;
                        }

                        /* Common case where 'jump_false' is next insn. */
                        if (fp->jf == 0) {
                                insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
                                target = i + fp->jt + 1;
                                BPF_EMIT_JMP;
                                break;
                        }

                        /* Convert some jumps when 'jump_true' is next insn. */
                        if (fp->jt == 0) {
                                switch (BPF_OP(fp->code)) {
                                case BPF_JEQ:
                                        insn->code = BPF_JMP | BPF_JNE | bpf_src;
                                        break;
                                case BPF_JGT:
                                        insn->code = BPF_JMP | BPF_JLE | bpf_src;
                                        break;
                                case BPF_JGE:
                                        insn->code = BPF_JMP | BPF_JLT | bpf_src;
                                        break;
                                default:
                                        goto jmp_rest;
                                }

                                target = i + fp->jf + 1;
                                BPF_EMIT_JMP;
                                break;
                        }
jmp_rest:
                        /* Other jumps are mapped into two insns: Jxx and JA. */
                        target = i + fp->jt + 1;
                        insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
                        BPF_EMIT_JMP;
                        insn++;

                        insn->code = BPF_JMP | BPF_JA;
                        target = i + fp->jf + 1;
                        BPF_EMIT_JMP;
                        break;

                /* ldxb 4 * ([14] & 0xf) is remapped into 6 insns. */
                case BPF_LDX | BPF_MSH | BPF_B: {
                        struct sock_filter tmp = {
                                .code   = BPF_LD | BPF_ABS | BPF_B,
                                .k      = fp->k,
                        };

                        *seen_ld_abs = true;

                        /* X = A */
                        *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
                        /* A = BPF_R0 = *(u8 *) (skb->data + K) */
                        convert_bpf_ld_abs(&tmp, &insn);
                        insn++;
                        /* A &= 0xf */
                        *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, 0xf);
                        /* A <<= 2 */
                        *insn++ = BPF_ALU32_IMM(BPF_LSH, BPF_REG_A, 2);
                        /* tmp = X */
                        *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_X);
                        /* X = A */
                        *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
                        /* A = tmp */
                        *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_TMP);
                        break;
                }
                /* RET_K is remapped into 2 insns. RET_A case doesn't need an
                 * extra mov as BPF_REG_0 is already mapped into BPF_REG_A.
                 */
                case BPF_RET | BPF_A:
                case BPF_RET | BPF_K:
                        if (BPF_RVAL(fp->code) == BPF_K)
                                *insn++ = BPF_MOV32_RAW(BPF_K, BPF_REG_0,
                                                        0, fp->k);
                        *insn = BPF_EXIT_INSN();
                        break;

                /* Store to stack. */
                case BPF_ST:
                case BPF_STX:
                        stack_off = fp->k * 4  + 4;
                        *insn = BPF_STX_MEM(BPF_W, BPF_REG_FP, BPF_CLASS(fp->code) ==
                                            BPF_ST ? BPF_REG_A : BPF_REG_X,
                                            -stack_off);
                        /* check_load_and_stores() verifies that classic BPF can
                         * load from stack only after write, so tracking
                         * stack_depth for ST|STX insns is enough
                         */
                        if (new_prog && new_prog->aux->stack_depth < stack_off)
                                new_prog->aux->stack_depth = stack_off;
                        break;

                /* Load from stack. */
                case BPF_LD | BPF_MEM:
                case BPF_LDX | BPF_MEM:
                        stack_off = fp->k * 4  + 4;
                        *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD  ?
                                            BPF_REG_A : BPF_REG_X, BPF_REG_FP,
                                            -stack_off);
                        break;

                /* A = K or X = K */
                case BPF_LD | BPF_IMM:
                case BPF_LDX | BPF_IMM:
                        *insn = BPF_MOV32_IMM(BPF_CLASS(fp->code) == BPF_LD ?
                                              BPF_REG_A : BPF_REG_X, fp->k);
                        break;

                /* X = A */
                case BPF_MISC | BPF_TAX:
                        *insn = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
                        break;

                /* A = X */
                case BPF_MISC | BPF_TXA:
                        *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_X);
                        break;

                /* A = skb->len or X = skb->len */
                case BPF_LD | BPF_W | BPF_LEN:
                case BPF_LDX | BPF_W | BPF_LEN:
                        *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
                                            BPF_REG_A : BPF_REG_X, BPF_REG_CTX,
                                            offsetof(struct sk_buff, len));
                        break;

                /* Access seccomp_data fields. */
                case BPF_LDX | BPF_ABS | BPF_W:
                        /* A = *(u32 *) (ctx + K) */
                        *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, fp->k);
                        break;

                /* Unknown instruction. */
                default:
                        goto err;
                }

                insn++;
                if (new_prog)
                        memcpy(new_insn, tmp_insns,
                               sizeof(*insn) * (insn - tmp_insns));
                new_insn += insn - tmp_insns;
        }

        if (!new_prog) {
                /* Only calculating new length. */
                *new_len = new_insn - first_insn;
                if (*seen_ld_abs)
                        *new_len += 4; /* Prologue bits. */
                return 0;
        }

        pass++;
        if (new_flen != new_insn - first_insn) {
                new_flen = new_insn - first_insn;
                if (pass > 2)
                        goto err;
                goto do_pass;
        }

        kfree(addrs);
        BUG_ON(*new_len != new_flen);
        return 0;
err:
        kfree(addrs);
        return -EINVAL;
}

/* Security:
 *
 * As we dont want to clear mem[] array for each packet going through
 * __bpf_prog_run(), we check that filter loaded by user never try to read
 * a cell if not previously written, and we check all branches to be sure
 * a malicious user doesn't try to abuse us.
 */
static int check_load_and_stores(const struct sock_filter *filter, int flen)
{
        u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */
        int pc, ret = 0;

        BUILD_BUG_ON(BPF_MEMWORDS > 16);

        masks = kmalloc_array(flen, sizeof(*masks), GFP_KERNEL);
        if (!masks)
                return -ENOMEM;

        memset(masks, 0xff, flen * sizeof(*masks));

        for (pc = 0; pc < flen; pc++) {
                memvalid &= masks[pc];

                switch (filter[pc].code) {
                case BPF_ST:
                case BPF_STX:
                        memvalid |= (1 << filter[pc].k);
                        break;
                case BPF_LD | BPF_MEM:
                case BPF_LDX | BPF_MEM:
                        if (!(memvalid & (1 << filter[pc].k))) {
                                ret = -EINVAL;
                                goto error;
                        }
                        break;
                case BPF_JMP | BPF_JA:
                        /* A jump must set masks on target */
                        masks[pc + 1 + filter[pc].k] &= memvalid;
                        memvalid = ~0;
                        break;
                case BPF_JMP | BPF_JEQ | BPF_K:
                case BPF_JMP | BPF_JEQ | BPF_X:
                case BPF_JMP | BPF_JGE | BPF_K:
                case BPF_JMP | BPF_JGE | BPF_X:
                case BPF_JMP | BPF_JGT | BPF_K:
                case BPF_JMP | BPF_JGT | BPF_X:
                case BPF_JMP | BPF_JSET | BPF_K:
                case BPF_JMP | BPF_JSET | BPF_X:
                        /* A jump must set masks on targets */
                        masks[pc + 1 + filter[pc].jt] &= memvalid;
                        masks[pc + 1 + filter[pc].jf] &= memvalid;
                        memvalid = ~0;
                        break;
                }
        }
error:
        kfree(masks);
        return ret;
}

static bool chk_code_allowed(u16 code_to_probe)
{
        static const bool codes[] = {
                /* 32 bit ALU operations */
                [BPF_ALU | BPF_ADD | BPF_K] = true,
                [BPF_ALU | BPF_ADD | BPF_X] = true,
                [BPF_ALU | BPF_SUB | BPF_K] = true,
                [BPF_ALU | BPF_SUB | BPF_X] = true,
                [BPF_ALU | BPF_MUL | BPF_K] = true,
                [BPF_ALU | BPF_MUL | BPF_X] = true,
                [BPF_ALU | BPF_DIV | BPF_K] = true,
                [BPF_ALU | BPF_DIV | BPF_X] = true,
                [BPF_ALU | BPF_MOD | BPF_K] = true,
                [BPF_ALU | BPF_MOD | BPF_X] = true,
                [BPF_ALU | BPF_AND | BPF_K] = true,
                [BPF_ALU | BPF_AND | BPF_X] = true,
                [BPF_ALU | BPF_OR | BPF_K] = true,
                [BPF_ALU | BPF_OR | BPF_X] = true,
                [BPF_ALU | BPF_XOR | BPF_K] = true,
                [BPF_ALU | BPF_XOR | BPF_X] = true,
                [BPF_ALU | BPF_LSH | BPF_K] = true,
                [BPF_ALU | BPF_LSH | BPF_X] = true,
                [BPF_ALU | BPF_RSH | BPF_K] = true,
                [BPF_ALU | BPF_RSH | BPF_X] = true,
                [BPF_ALU | BPF_NEG] = true,
                /* Load instructions */
                [BPF_LD | BPF_W | BPF_ABS] = true,
                [BPF_LD | BPF_H | BPF_ABS] = true,
                [BPF_LD | BPF_B | BPF_ABS] = true,
                [BPF_LD | BPF_W | BPF_LEN] = true,
                [BPF_LD | BPF_W | BPF_IND] = true,
                [BPF_LD | BPF_H | BPF_IND] = true,
                [BPF_LD | BPF_B | BPF_IND] = true,
                [BPF_LD | BPF_IMM] = true,
                [BPF_LD | BPF_MEM] = true,
                [BPF_LDX | BPF_W | BPF_LEN] = true,
                [BPF_LDX | BPF_B | BPF_MSH] = true,
                [BPF_LDX | BPF_IMM] = true,
                [BPF_LDX | BPF_MEM] = true,
                /* Store instructions */
                [BPF_ST] = true,
                [BPF_STX] = true,
                /* Misc instructions */
                [BPF_MISC | BPF_TAX] = true,
                [BPF_MISC | BPF_TXA] = true,
                /* Return instructions */
                [BPF_RET | BPF_K] = true,
                [BPF_RET | BPF_A] = true,
                /* Jump instructions */
                [BPF_JMP | BPF_JA] = true,
                [BPF_JMP | BPF_JEQ | BPF_K] = true,
                [BPF_JMP | BPF_JEQ | BPF_X] = true,
                [BPF_JMP | BPF_JGE | BPF_K] = true,
                [BPF_JMP | BPF_JGE | BPF_X] = true,
                [BPF_JMP | BPF_JGT | BPF_K] = true,
                [BPF_JMP | BPF_JGT | BPF_X] = true,
                [BPF_JMP | BPF_JSET | BPF_K] = true,
                [BPF_JMP | BPF_JSET | BPF_X] = true,
        };

        if (code_to_probe >= ARRAY_SIZE(codes))
                return false;

        return codes[code_to_probe];
}

static bool bpf_check_basics_ok(const struct sock_filter *filter,
                                unsigned int flen)
{
        if (filter == NULL)
                return false;
        if (flen == 0 || flen > BPF_MAXINSNS)
                return false;

        return true;
}

/**
 *      bpf_check_classic - verify socket filter code
 *      @filter: filter to verify
 *      @flen: length of filter
 *
 * Check the user's filter code. If we let some ugly
 * filter code slip through kaboom! The filter must contain
 * no references or jumps that are out of range, no illegal
 * instructions, and must end with a RET instruction.
 *
 * All jumps are forward as they are not signed.
 *
 * Returns 0 if the rule set is legal or -EINVAL if not.
 */
static int bpf_check_classic(const struct sock_filter *filter,
                             unsigned int flen)
{
        bool anc_found;
        int pc;

        /* Check the filter code now */
        for (pc = 0; pc < flen; pc++) {
                const struct sock_filter *ftest = &filter[pc];

                /* May we actually operate on this code? */
                if (!chk_code_allowed(ftest->code))
                        return -EINVAL;

                /* Some instructions need special checks */
                switch (ftest->code) {
                case BPF_ALU | BPF_DIV | BPF_K:
                case BPF_ALU | BPF_MOD | BPF_K:
                        /* Check for division by zero */
                        if (ftest->k == 0)
                                return -EINVAL;
                        break;
                case BPF_ALU | BPF_LSH | BPF_K:
                case BPF_ALU | BPF_RSH | BPF_K:
                        if (ftest->k >= 32)
                                return -EINVAL;
                        break;
                case BPF_LD | BPF_MEM:
                case BPF_LDX | BPF_MEM:
                case BPF_ST:
                case BPF_STX:
                        /* Check for invalid memory addresses */
                        if (ftest->k >= BPF_MEMWORDS)
                                return -EINVAL;
                        break;
                case BPF_JMP | BPF_JA:
                        /* Note, the large ftest->k might cause loops.
                         * Compare this with conditional jumps below,
                         * where offsets are limited. --ANK (981016)
                         */
                        if (ftest->k >= (unsigned int)(flen - pc - 1))
                                return -EINVAL;
                        break;
                case BPF_JMP | BPF_JEQ | BPF_K:
                case BPF_JMP | BPF_JEQ | BPF_X:
                case BPF_JMP | BPF_JGE | BPF_K:
                case BPF_JMP | BPF_JGE | BPF_X:
                case BPF_JMP | BPF_JGT | BPF_K:
                case BPF_JMP | BPF_JGT | BPF_X:
                case BPF_JMP | BPF_JSET | BPF_K:
                case BPF_JMP | BPF_JSET | BPF_X:
                        /* Both conditionals must be safe */
                        if (pc + ftest->jt + 1 >= flen ||
                            pc + ftest->jf + 1 >= flen)
                                return -EINVAL;
                        break;
                case BPF_LD | BPF_W | BPF_ABS:
                case BPF_LD | BPF_H | BPF_ABS:
                case BPF_LD | BPF_B | BPF_ABS:
                        anc_found = false;
                        if (bpf_anc_helper(ftest) & BPF_ANC)
                                anc_found = true;
                        /* Ancillary operation unknown or unsupported */
                        if (anc_found == false && ftest->k >= SKF_AD_OFF)
                                return -EINVAL;
                }
        }

        /* Last instruction must be a RET code */
        switch (filter[flen - 1].code) {
        case BPF_RET | BPF_K:
        case BPF_RET | BPF_A:
                return check_load_and_stores(filter, flen);
        }

        return -EINVAL;
}

static int bpf_prog_store_orig_filter(struct bpf_prog *fp,
                                      const struct sock_fprog *fprog)
{
        unsigned int fsize = bpf_classic_proglen(fprog);
        struct sock_fprog_kern *fkprog;

        fp->orig_prog = kmalloc_obj(*fkprog);
        if (!fp->orig_prog)
                return -ENOMEM;

        fkprog = fp->orig_prog;
        fkprog->len = fprog->len;

        fkprog->filter = kmemdup(fp->insns, fsize,
                                 GFP_KERNEL | __GFP_NOWARN);
        if (!fkprog->filter) {
                kfree(fp->orig_prog);
                return -ENOMEM;
        }

        return 0;
}

static void bpf_release_orig_filter(struct bpf_prog *fp)
{
        struct sock_fprog_kern *fprog = fp->orig_prog;

        if (fprog) {
                kfree(fprog->filter);
                kfree(fprog);
        }
}

static void __bpf_prog_release(struct bpf_prog *prog)
{
        if (prog->type == BPF_PROG_TYPE_SOCKET_FILTER) {
                bpf_prog_put(prog);
        } else {
                bpf_release_orig_filter(prog);
                bpf_prog_free(prog);
        }
}

static void __sk_filter_release(struct sk_filter *fp)
{
        __bpf_prog_release(fp->prog);
        kfree(fp);
}

/**
 *      sk_filter_release_rcu - Release a socket filter by rcu_head
 *      @rcu: rcu_head that contains the sk_filter to free
 */
static void sk_filter_release_rcu(struct rcu_head *rcu)
{
        struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);

        __sk_filter_release(fp);
}

/**
 *      sk_filter_release - release a socket filter
 *      @fp: filter to remove
 *
 *      Remove a filter from a socket and release its resources.
 */
static void sk_filter_release(struct sk_filter *fp)
{
        if (refcount_dec_and_test(&fp->refcnt))
                call_rcu(&fp->rcu, sk_filter_release_rcu);
}

void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
{
        u32 filter_size = bpf_prog_size(fp->prog->len);

        atomic_sub(filter_size, &sk->sk_omem_alloc);
        sk_filter_release(fp);
}

/* try to charge the socket memory if there is space available
 * return true on success
 */
static bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp)
{
        int optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max);
        u32 filter_size = bpf_prog_size(fp->prog->len);

        /* same check as in sock_kmalloc() */
        if (filter_size <= optmem_max &&
            atomic_read(&sk->sk_omem_alloc) + filter_size < optmem_max) {
                atomic_add(filter_size, &sk->sk_omem_alloc);
                return true;
        }
        return false;
}

bool sk_filter_charge(struct sock *sk, struct sk_filter *fp)
{
        if (!refcount_inc_not_zero(&fp->refcnt))
                return false;

        if (!__sk_filter_charge(sk, fp)) {
                sk_filter_release(fp);
                return false;
        }
        return true;
}

static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp)
{
        struct sock_filter *old_prog;
        struct bpf_prog *old_fp;
        int err, new_len, old_len = fp->len;
        bool seen_ld_abs = false;

        /* We are free to overwrite insns et al right here as it won't be used at
         * this point in time anymore internally after the migration to the eBPF
         * instruction representation.
         */
        BUILD_BUG_ON(sizeof(struct sock_filter) !=
                     sizeof(struct bpf_insn));

        /* Conversion cannot happen on overlapping memory areas,
         * so we need to keep the user BPF around until the 2nd
         * pass. At this time, the user BPF is stored in fp->insns.
         */
        old_prog = kmemdup_array(fp->insns, old_len, sizeof(struct sock_filter),
                                 GFP_KERNEL | __GFP_NOWARN);
        if (!old_prog) {
                err = -ENOMEM;
                goto out_err;
        }

        /* 1st pass: calculate the new program length. */
        err = bpf_convert_filter(old_prog, old_len, NULL, &new_len,
                                 &seen_ld_abs);
        if (err)
                goto out_err_free;

        /* Expand fp for appending the new filter representation. */
        old_fp = fp;
        fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0);
        if (!fp) {
                /* The old_fp is still around in case we couldn't
                 * allocate new memory, so uncharge on that one.
                 */
                fp = old_fp;
                err = -ENOMEM;
                goto out_err_free;
        }

        fp->len = new_len;

        /* 2nd pass: remap sock_filter insns into bpf_insn insns. */
        err = bpf_convert_filter(old_prog, old_len, fp, &new_len,
                                 &seen_ld_abs);
        if (err)
                /* 2nd bpf_convert_filter() can fail only if it fails
                 * to allocate memory, remapping must succeed. Note,
                 * that at this time old_fp has already been released
                 * by krealloc().
                 */
                goto out_err_free;

        fp = bpf_prog_select_runtime(fp, &err);
        if (err)
                goto out_err_free;

        kfree(old_prog);
        return fp;

out_err_free:
        kfree(old_prog);
out_err:
        __bpf_prog_release(fp);
        return ERR_PTR(err);
}

static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp,
                                           bpf_aux_classic_check_t trans)
{
        int err;

        fp->bpf_func = NULL;
        fp->jited = 0;

        err = bpf_check_classic(fp->insns, fp->len);
        if (err) {
                __bpf_prog_release(fp);
                return ERR_PTR(err);
        }

        /* There might be additional checks and transformations
         * needed on classic filters, f.e. in case of seccomp.
         */
        if (trans) {
                err = trans(fp->insns, fp->len);
                if (err) {
                        __bpf_prog_release(fp);
                        return ERR_PTR(err);
                }
        }

        /* Probe if we can JIT compile the filter and if so, do
         * the compilation of the filter.
         */
        bpf_jit_compile(fp);

        /* JIT compiler couldn't process this filter, so do the eBPF translation
         * for the optimized interpreter.
         */
        if (!fp->jited)
                fp = bpf_migrate_filter(fp);

        return fp;
}

/**
 *      bpf_prog_create - create an unattached filter
 *      @pfp: the unattached filter that is created
 *      @fprog: the filter program
 *
 * Create a filter independent of any socket. We first run some
 * sanity checks on it to make sure it does not explode on us later.
 * If an error occurs or there is insufficient memory for the filter
 * a negative errno code is returned. On success the return is zero.
 */
int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog)
{
        unsigned int fsize = bpf_classic_proglen(fprog);
        struct bpf_prog *fp;

        /* Make sure new filter is there and in the right amounts. */
        if (!bpf_check_basics_ok(fprog->filter, fprog->len))
                return -EINVAL;

        fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
        if (!fp)
                return -ENOMEM;

        memcpy(fp->insns, fprog->filter, fsize);

        fp->len = fprog->len;
        /* Since unattached filters are not copied back to user
         * space through sk_get_filter(), we do not need to hold
         * a copy here, and can spare us the work.
         */
        fp->orig_prog = NULL;

        /* bpf_prepare_filter() already takes care of freeing
         * memory in case something goes wrong.
         */
        fp = bpf_prepare_filter(fp, NULL);
        if (IS_ERR(fp))
                return PTR_ERR(fp);

        *pfp = fp;
        return 0;
}
EXPORT_SYMBOL_GPL(bpf_prog_create);

/**
 *      bpf_prog_create_from_user - create an unattached filter from user buffer
 *      @pfp: the unattached filter that is created
 *      @fprog: the filter program
 *      @trans: post-classic verifier transformation handler
 *      @save_orig: save classic BPF program
 *
 * This function effectively does the same as bpf_prog_create(), only
 * that it builds up its insns buffer from user space provided buffer.
 * It also allows for passing a bpf_aux_classic_check_t handler.
 */
int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
                              bpf_aux_classic_check_t trans, bool save_orig)
{
        unsigned int fsize = bpf_classic_proglen(fprog);
        struct bpf_prog *fp;
        int err;

        /* Make sure new filter is there and in the right amounts. */
        if (!bpf_check_basics_ok(fprog->filter, fprog->len))
                return -EINVAL;

        fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
        if (!fp)
                return -ENOMEM;

        if (copy_from_user(fp->insns, fprog->filter, fsize)) {
                __bpf_prog_free(fp);
                return -EFAULT;
        }

        fp->len = fprog->len;
        fp->orig_prog = NULL;

        if (save_orig) {
                err = bpf_prog_store_orig_filter(fp, fprog);
                if (err) {
                        __bpf_prog_free(fp);
                        return -ENOMEM;
                }
        }

        /* bpf_prepare_filter() already takes care of freeing
         * memory in case something goes wrong.
         */
        fp = bpf_prepare_filter(fp, trans);
        if (IS_ERR(fp))
                return PTR_ERR(fp);

        *pfp = fp;
        return 0;
}
EXPORT_SYMBOL_GPL(bpf_prog_create_from_user);

void bpf_prog_destroy(struct bpf_prog *fp)
{
        __bpf_prog_release(fp);
}
EXPORT_SYMBOL_GPL(bpf_prog_destroy);

static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk)
{
        struct sk_filter *fp, *old_fp;

        fp = kmalloc_obj(*fp);
        if (!fp)
                return -ENOMEM;

        fp->prog = prog;

        if (!__sk_filter_charge(sk, fp)) {
                kfree(fp);
                return -ENOMEM;
        }
        refcount_set(&fp->refcnt, 1);

        old_fp = rcu_dereference_protected(sk->sk_filter,
                                           lockdep_sock_is_held(sk));
        rcu_assign_pointer(sk->sk_filter, fp);

        if (old_fp)
                sk_filter_uncharge(sk, old_fp);

        return 0;
}

static
struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk)
{
        unsigned int fsize = bpf_classic_proglen(fprog);
        struct bpf_prog *prog;
        int err;

        if (sock_flag(sk, SOCK_FILTER_LOCKED))
                return ERR_PTR(-EPERM);

        /* Make sure new filter is there and in the right amounts. */
        if (!bpf_check_basics_ok(fprog->filter, fprog->len))
                return ERR_PTR(-EINVAL);

        prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
        if (!prog)
                return ERR_PTR(-ENOMEM);

        if (copy_from_user(prog->insns, fprog->filter, fsize)) {
                __bpf_prog_free(prog);
                return ERR_PTR(-EFAULT);
        }

        prog->len = fprog->len;

        err = bpf_prog_store_orig_filter(prog, fprog);
        if (err) {
                __bpf_prog_free(prog);
                return ERR_PTR(-ENOMEM);
        }

        /* bpf_prepare_filter() already takes care of freeing
         * memory in case something goes wrong.
         */
        return bpf_prepare_filter(prog, NULL);
}

/**
 *      sk_attach_filter - attach a socket filter
 *      @fprog: the filter program
 *      @sk: the socket to use
 *
 * Attach the user's filter code. We first run some sanity checks on
 * it to make sure it does not explode on us later. If an error
 * occurs or there is insufficient memory for the filter a negative
 * errno code is returned. On success the return is zero.
 */
int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
{
        struct bpf_prog *prog = __get_filter(fprog, sk);
        int err;

        if (IS_ERR(prog))
                return PTR_ERR(prog);

        err = __sk_attach_prog(prog, sk);
        if (err < 0) {
                __bpf_prog_release(prog);
                return err;
        }

        return 0;
}
EXPORT_SYMBOL_GPL(sk_attach_filter);

int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk)
{
        struct bpf_prog *prog = __get_filter(fprog, sk);
        int err, optmem_max;

        if (IS_ERR(prog))
                return PTR_ERR(prog);

        optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max);
        if (bpf_prog_size(prog->len) > optmem_max)
                err = -ENOMEM;
        else
                err = reuseport_attach_prog(sk, prog);

        if (err)
                __bpf_prog_release(prog);

        return err;
}

static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk)
{
        if (sock_flag(sk, SOCK_FILTER_LOCKED))
                return ERR_PTR(-EPERM);

        return bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
}

int sk_attach_bpf(u32 ufd, struct sock *sk)
{
        struct bpf_prog *prog = __get_bpf(ufd, sk);
        int err;

        if (IS_ERR(prog))
                return PTR_ERR(prog);

        err = __sk_attach_prog(prog, sk);
        if (err < 0) {
                bpf_prog_put(prog);
                return err;
        }

        return 0;
}

int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk)
{
        struct bpf_prog *prog;
        int err, optmem_max;

        if (sock_flag(sk, SOCK_FILTER_LOCKED))
                return -EPERM;

        prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
        if (PTR_ERR(prog) == -EINVAL)
                prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SK_REUSEPORT);
        if (IS_ERR(prog))
                return PTR_ERR(prog);

        if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT) {
                /* Like other non BPF_PROG_TYPE_SOCKET_FILTER
                 * bpf prog (e.g. sockmap).  It depends on the
                 * limitation imposed by bpf_prog_load().
                 * Hence, sysctl_optmem_max is not checked.
                 */
                if ((sk->sk_type != SOCK_STREAM &&
                     sk->sk_type != SOCK_DGRAM) ||
                    (sk->sk_protocol != IPPROTO_UDP &&
                     sk->sk_protocol != IPPROTO_TCP) ||
                    (sk->sk_family != AF_INET &&
                     sk->sk_family != AF_INET6)) {
                        err = -ENOTSUPP;
                        goto err_prog_put;
                }
        } else {
                /* BPF_PROG_TYPE_SOCKET_FILTER */
                optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max);
                if (bpf_prog_size(prog->len) > optmem_max) {
                        err = -ENOMEM;
                        goto err_prog_put;
                }
        }

        err = reuseport_attach_prog(sk, prog);
err_prog_put:
        if (err)
                bpf_prog_put(prog);

        return err;
}

static void sk_reuseport_prog_free_rcu(struct rcu_head *rcu)
{
        struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
        struct bpf_prog *prog = aux->prog;

        bpf_release_orig_filter(prog);
        bpf_prog_free(prog);
}

void sk_reuseport_prog_free(struct bpf_prog *prog)
{
        if (!prog)
                return;

        if (bpf_prog_was_classic(prog))
                call_rcu(&prog->aux->rcu, sk_reuseport_prog_free_rcu);
        else
                bpf_prog_put(prog);
}

static inline int __bpf_try_make_writable(struct sk_buff *skb,
                                          unsigned int write_len)
{
#ifdef CONFIG_DEBUG_NET
        /* Avoid a splat in pskb_may_pull_reason() */
        if (write_len > INT_MAX)
                return -EINVAL;
#endif
        return skb_ensure_writable(skb, write_len);
}

static inline int bpf_try_make_writable(struct sk_buff *skb,
                                        unsigned int write_len)
{
        int err = __bpf_try_make_writable(skb, write_len);

        bpf_compute_data_pointers(skb);
        return err;
}

static int bpf_try_make_head_writable(struct sk_buff *skb)
{
        return bpf_try_make_writable(skb, skb_headlen(skb));
}

static inline void bpf_push_mac_rcsum(struct sk_buff *skb)
{
        if (skb_at_tc_ingress(skb))
                skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len);
}

static inline void bpf_pull_mac_rcsum(struct sk_buff *skb)
{
        if (skb_at_tc_ingress(skb))
                skb_postpull_rcsum(skb, skb_mac_header(skb), skb->mac_len);
}

BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset,
           const void *, from, u32, len, u64, flags)
{
        void *ptr;

        if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH)))
                return -EINVAL;
        if (unlikely(offset > INT_MAX))
                return -EFAULT;
        if (unlikely(bpf_try_make_writable(skb, offset + len)))
                return -EFAULT;

        ptr = skb->data + offset;
        if (flags & BPF_F_RECOMPUTE_CSUM)
                __skb_postpull_rcsum(skb, ptr, len, offset);

        memcpy(ptr, from, len);

        if (flags & BPF_F_RECOMPUTE_CSUM)
                __skb_postpush_rcsum(skb, ptr, len, offset);
        if (flags & BPF_F_INVALIDATE_HASH)
                skb_clear_hash(skb);

        return 0;
}

static const struct bpf_func_proto bpf_skb_store_bytes_proto = {
        .func           = bpf_skb_store_bytes,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg4_type      = ARG_CONST_SIZE,
        .arg5_type      = ARG_ANYTHING,
};

int __bpf_skb_store_bytes(struct sk_buff *skb, u32 offset, const void *from,
                          u32 len, u64 flags)
{
        return ____bpf_skb_store_bytes(skb, offset, from, len, flags);
}

BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset,
           void *, to, u32, len)
{
        void *ptr;

        if (unlikely(offset > INT_MAX))
                goto err_clear;

        ptr = skb_header_pointer(skb, offset, len, to);
        if (unlikely(!ptr))
                goto err_clear;
        if (ptr != to)
                memcpy(to, ptr, len);

        return 0;
err_clear:
        memset(to, 0, len);
        return -EFAULT;
}

static const struct bpf_func_proto bpf_skb_load_bytes_proto = {
        .func           = bpf_skb_load_bytes,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_PTR_TO_UNINIT_MEM,
        .arg4_type      = ARG_CONST_SIZE,
};

int __bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, void *to, u32 len)
{
        return ____bpf_skb_load_bytes(skb, offset, to, len);
}

BPF_CALL_4(bpf_flow_dissector_load_bytes,
           const struct bpf_flow_dissector *, ctx, u32, offset,
           void *, to, u32, len)
{
        void *ptr;

        if (unlikely(offset > 0xffff))
                goto err_clear;

        if (unlikely(!ctx->skb))
                goto err_clear;

        ptr = skb_header_pointer(ctx->skb, offset, len, to);
        if (unlikely(!ptr))
                goto err_clear;
        if (ptr != to)
                memcpy(to, ptr, len);

        return 0;
err_clear:
        memset(to, 0, len);
        return -EFAULT;
}

static const struct bpf_func_proto bpf_flow_dissector_load_bytes_proto = {
        .func           = bpf_flow_dissector_load_bytes,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_PTR_TO_UNINIT_MEM,
        .arg4_type      = ARG_CONST_SIZE,
};

BPF_CALL_5(bpf_skb_load_bytes_relative, const struct sk_buff *, skb,
           u32, offset, void *, to, u32, len, u32, start_header)
{
        u8 *end = skb_tail_pointer(skb);
        u8 *start, *ptr;

        if (unlikely(offset > 0xffff))
                goto err_clear;

        switch (start_header) {
        case BPF_HDR_START_MAC:
                if (unlikely(!skb_mac_header_was_set(skb)))
                        goto err_clear;
                start = skb_mac_header(skb);
                break;
        case BPF_HDR_START_NET:
                start = skb_network_header(skb);
                break;
        default:
                goto err_clear;
        }

        ptr = start + offset;

        if (likely(ptr + len <= end)) {
                memcpy(to, ptr, len);
                return 0;
        }

err_clear:
        memset(to, 0, len);
        return -EFAULT;
}

static const struct bpf_func_proto bpf_skb_load_bytes_relative_proto = {
        .func           = bpf_skb_load_bytes_relative,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_PTR_TO_UNINIT_MEM,
        .arg4_type      = ARG_CONST_SIZE,
        .arg5_type      = ARG_ANYTHING,
};

BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len)
{
        /* Idea is the following: should the needed direct read/write
         * test fail during runtime, we can pull in more data and redo
         * again, since implicitly, we invalidate previous checks here.
         *
         * Or, since we know how much we need to make read/writeable,
         * this can be done once at the program beginning for direct
         * access case. By this we overcome limitations of only current
         * headroom being accessible.
         */
        return bpf_try_make_writable(skb, len ? : skb_headlen(skb));
}

static const struct bpf_func_proto bpf_skb_pull_data_proto = {
        .func           = bpf_skb_pull_data,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
};

BPF_CALL_1(bpf_sk_fullsock, struct sock *, sk)
{
        return sk_fullsock(sk) ? (unsigned long)sk : (unsigned long)NULL;
}

static const struct bpf_func_proto bpf_sk_fullsock_proto = {
        .func           = bpf_sk_fullsock,
        .gpl_only       = false,
        .ret_type       = RET_PTR_TO_SOCKET_OR_NULL,
        .arg1_type      = ARG_PTR_TO_SOCK_COMMON,
};

static inline int sk_skb_try_make_writable(struct sk_buff *skb,
                                           unsigned int write_len)
{
        return __bpf_try_make_writable(skb, write_len);
}

BPF_CALL_2(sk_skb_pull_data, struct sk_buff *, skb, u32, len)
{
        /* Idea is the following: should the needed direct read/write
         * test fail during runtime, we can pull in more data and redo
         * again, since implicitly, we invalidate previous checks here.
         *
         * Or, since we know how much we need to make read/writeable,
         * this can be done once at the program beginning for direct
         * access case. By this we overcome limitations of only current
         * headroom being accessible.
         */
        return sk_skb_try_make_writable(skb, len ? : skb_headlen(skb));
}

static const struct bpf_func_proto sk_skb_pull_data_proto = {
        .func           = sk_skb_pull_data,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
};

BPF_CALL_5(bpf_l3_csum_replace, struct sk_buff *, skb, u32, offset,
           u64, from, u64, to, u64, flags)
{
        __sum16 *ptr;

        if (unlikely(flags & ~(BPF_F_HDR_FIELD_MASK)))
                return -EINVAL;
        if (unlikely(offset > 0xffff || offset & 1))
                return -EFAULT;
        if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
                return -EFAULT;

        ptr = (__sum16 *)(skb->data + offset);
        switch (flags & BPF_F_HDR_FIELD_MASK) {
        case 0:
                if (unlikely(from != 0))
                        return -EINVAL;

                csum_replace_by_diff(ptr, to);
                break;
        case 2:
                csum_replace2(ptr, from, to);
                break;
        case 4:
                csum_replace4(ptr, from, to);
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static const struct bpf_func_proto bpf_l3_csum_replace_proto = {
        .func           = bpf_l3_csum_replace,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_ANYTHING,
        .arg5_type      = ARG_ANYTHING,
};

BPF_CALL_5(bpf_l4_csum_replace, struct sk_buff *, skb, u32, offset,
           u64, from, u64, to, u64, flags)
{
        bool is_pseudo = flags & BPF_F_PSEUDO_HDR;
        bool is_mmzero = flags & BPF_F_MARK_MANGLED_0;
        bool do_mforce = flags & BPF_F_MARK_ENFORCE;
        bool is_ipv6   = flags & BPF_F_IPV6;
        __sum16 *ptr;

        if (unlikely(flags & ~(BPF_F_MARK_MANGLED_0 | BPF_F_MARK_ENFORCE |
                               BPF_F_PSEUDO_HDR | BPF_F_HDR_FIELD_MASK | BPF_F_IPV6)))
                return -EINVAL;
        if (unlikely(offset > 0xffff || offset & 1))
                return -EFAULT;
        if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
                return -EFAULT;

        ptr = (__sum16 *)(skb->data + offset);
        if (is_mmzero && !do_mforce && !*ptr)
                return 0;

        switch (flags & BPF_F_HDR_FIELD_MASK) {
        case 0:
                if (unlikely(from != 0))
                        return -EINVAL;

                inet_proto_csum_replace_by_diff(ptr, skb, to, is_pseudo, is_ipv6);
                break;
        case 2:
                inet_proto_csum_replace2(ptr, skb, from, to, is_pseudo);
                break;
        case 4:
                inet_proto_csum_replace4(ptr, skb, from, to, is_pseudo);
                break;
        default:
                return -EINVAL;
        }

        if (is_mmzero && !*ptr)
                *ptr = CSUM_MANGLED_0;
        return 0;
}

static const struct bpf_func_proto bpf_l4_csum_replace_proto = {
        .func           = bpf_l4_csum_replace,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_ANYTHING,
        .arg5_type      = ARG_ANYTHING,
};

BPF_CALL_5(bpf_csum_diff, __be32 *, from, u32, from_size,
           __be32 *, to, u32, to_size, __wsum, seed)
{
        /* This is quite flexible, some examples:
         *
         * from_size == 0, to_size > 0,  seed := csum --> pushing data
         * from_size > 0,  to_size == 0, seed := csum --> pulling data
         * from_size > 0,  to_size > 0,  seed := 0    --> diffing data
         *
         * Even for diffing, from_size and to_size don't need to be equal.
         */

        __wsum ret = seed;

        if (from_size && to_size)
                ret = csum_sub(csum_partial(to, to_size, ret),
                               csum_partial(from, from_size, 0));
        else if (to_size)
                ret = csum_partial(to, to_size, ret);

        else if (from_size)
                ret = ~csum_partial(from, from_size, ~ret);

        return csum_from32to16((__force unsigned int)ret);
}

static const struct bpf_func_proto bpf_csum_diff_proto = {
        .func           = bpf_csum_diff,
        .gpl_only       = false,
        .pkt_access     = true,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
        .arg2_type      = ARG_CONST_SIZE_OR_ZERO,
        .arg3_type      = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
        .arg4_type      = ARG_CONST_SIZE_OR_ZERO,
        .arg5_type      = ARG_ANYTHING,
};

BPF_CALL_2(bpf_csum_update, struct sk_buff *, skb, __wsum, csum)
{
        /* The interface is to be used in combination with bpf_csum_diff()
         * for direct packet writes. csum rotation for alignment as well
         * as emulating csum_sub() can be done from the eBPF program.
         */
        if (skb->ip_summed == CHECKSUM_COMPLETE)
                return (skb->csum = csum_add(skb->csum, csum));

        return -ENOTSUPP;
}

static const struct bpf_func_proto bpf_csum_update_proto = {
        .func           = bpf_csum_update,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
};

BPF_CALL_2(bpf_csum_level, struct sk_buff *, skb, u64, level)
{
        /* The interface is to be used in combination with bpf_skb_adjust_room()
         * for encap/decap of packet headers when BPF_F_ADJ_ROOM_NO_CSUM_RESET
         * is passed as flags, for example.
         */
        switch (level) {
        case BPF_CSUM_LEVEL_INC:
                __skb_incr_checksum_unnecessary(skb);
                break;
        case BPF_CSUM_LEVEL_DEC:
                __skb_decr_checksum_unnecessary(skb);
                break;
        case BPF_CSUM_LEVEL_RESET:
                __skb_reset_checksum_unnecessary(skb);
                break;
        case BPF_CSUM_LEVEL_QUERY:
                return skb->ip_summed == CHECKSUM_UNNECESSARY ?
                       skb->csum_level : -EACCES;
        default:
                return -EINVAL;
        }

        return 0;
}

static const struct bpf_func_proto bpf_csum_level_proto = {
        .func           = bpf_csum_level,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
};

static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb)
{
        return dev_forward_skb_nomtu(dev, skb);
}

static inline int __bpf_rx_skb_no_mac(struct net_device *dev,
                                      struct sk_buff *skb)
{
        int ret = ____dev_forward_skb(dev, skb, false);

        if (likely(!ret)) {
                skb->dev = dev;
                ret = netif_rx(skb);
        }

        return ret;
}

static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)
{
        int ret;

        if (dev_xmit_recursion()) {
                net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
                kfree_skb(skb);
                return -ENETDOWN;
        }

        skb->dev = dev;
        skb_set_redirected_noclear(skb, skb_at_tc_ingress(skb));
        skb_clear_tstamp(skb);

        dev_xmit_recursion_inc();
        ret = dev_queue_xmit(skb);
        dev_xmit_recursion_dec();

        return ret;
}

static int __bpf_redirect_no_mac(struct sk_buff *skb, struct net_device *dev,
                                 u32 flags)
{
        unsigned int mlen = skb_network_offset(skb);

        if (unlikely(skb->len <= mlen)) {
                kfree_skb(skb);
                return -ERANGE;
        }

        if (mlen) {
                __skb_pull(skb, mlen);

                /* At ingress, the mac header has already been pulled once.
                 * At egress, skb_pospull_rcsum has to be done in case that
                 * the skb is originated from ingress (i.e. a forwarded skb)
                 * to ensure that rcsum starts at net header.
                 */
                if (!skb_at_tc_ingress(skb))
                        skb_postpull_rcsum(skb, skb_mac_header(skb), mlen);
        }
        skb_pop_mac_header(skb);
        skb_reset_mac_len(skb);
        return flags & BPF_F_INGRESS ?
               __bpf_rx_skb_no_mac(dev, skb) : __bpf_tx_skb(dev, skb);
}

static int __bpf_redirect_common(struct sk_buff *skb, struct net_device *dev,
                                 u32 flags)
{
        /* Verify that a link layer header is carried */
        if (unlikely(skb->mac_header >= skb->network_header || skb->len == 0)) {
                kfree_skb(skb);
                return -ERANGE;
        }

        bpf_push_mac_rcsum(skb);
        return flags & BPF_F_INGRESS ?
               __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb);
}

static int __bpf_redirect(struct sk_buff *skb, struct net_device *dev,
                          u32 flags)
{
        if (dev_is_mac_header_xmit(dev))
                return __bpf_redirect_common(skb, dev, flags);
        else
                return __bpf_redirect_no_mac(skb, dev, flags);
}

#if IS_ENABLED(CONFIG_IPV6)
static int bpf_out_neigh_v6(struct net *net, struct sk_buff *skb,
                            struct net_device *dev, struct bpf_nh_params *nh)
{
        u32 hh_len = LL_RESERVED_SPACE(dev);
        const struct in6_addr *nexthop;
        struct dst_entry *dst = NULL;
        struct neighbour *neigh;

        if (dev_xmit_recursion()) {
                net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
                goto out_drop;
        }

        skb->dev = dev;
        skb_clear_tstamp(skb);

        if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
                skb = skb_expand_head(skb, hh_len);
                if (!skb)
                        return -ENOMEM;
        }

        if (unlikely(!ipv6_mod_enabled()))
                goto out_drop;

        rcu_read_lock();
        if (!nh) {
                dst = skb_dst(skb);
                nexthop = rt6_nexthop(dst_rt6_info(dst),
                                      &ipv6_hdr(skb)->daddr);
        } else {
                nexthop = &nh->ipv6_nh;
        }
        neigh = ip_neigh_gw6(dev, nexthop);
        if (likely(!IS_ERR(neigh))) {
                int ret;

                sock_confirm_neigh(skb, neigh);
                local_bh_disable();
                dev_xmit_recursion_inc();
                ret = neigh_output(neigh, skb, false);
                dev_xmit_recursion_dec();
                local_bh_enable();
                rcu_read_unlock();
                return ret;
        }
        rcu_read_unlock();
        if (dst)
                IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
out_drop:
        kfree_skb(skb);
        return -ENETDOWN;
}

static int __bpf_redirect_neigh_v6(struct sk_buff *skb, struct net_device *dev,
                                   struct bpf_nh_params *nh)
{
        const struct ipv6hdr *ip6h = ipv6_hdr(skb);
        struct net *net = dev_net(dev);
        int err, ret = NET_XMIT_DROP;

        if (!nh) {
                struct dst_entry *dst;
                struct flowi6 fl6 = {
                        .flowi6_flags = FLOWI_FLAG_ANYSRC,
                        .flowi6_mark  = skb->mark,
                        .flowlabel    = ip6_flowinfo(ip6h),
                        .flowi6_oif   = dev->ifindex,
                        .flowi6_proto = ip6h->nexthdr,
                        .daddr        = ip6h->daddr,
                        .saddr        = ip6h->saddr,
                };

                dst = ip6_dst_lookup_flow(net, NULL, &fl6, NULL);
                if (IS_ERR(dst))
                        goto out_drop;

                skb_dst_drop(skb);
                skb_dst_set(skb, dst);
        } else if (nh->nh_family != AF_INET6) {
                goto out_drop;
        }

        err = bpf_out_neigh_v6(net, skb, dev, nh);
        if (unlikely(net_xmit_eval(err)))
                dev_core_stats_tx_dropped_inc(dev);
        else
                ret = NET_XMIT_SUCCESS;
        goto out_xmit;
out_drop:
        dev_core_stats_tx_dropped_inc(dev);
        kfree_skb(skb);
out_xmit:
        return ret;
}
#else
static int __bpf_redirect_neigh_v6(struct sk_buff *skb, struct net_device *dev,
                                   struct bpf_nh_params *nh)
{
        kfree_skb(skb);
        return NET_XMIT_DROP;
}
#endif /* CONFIG_IPV6 */

#if IS_ENABLED(CONFIG_INET)
static int bpf_out_neigh_v4(struct net *net, struct sk_buff *skb,
                            struct net_device *dev, struct bpf_nh_params *nh)
{
        u32 hh_len = LL_RESERVED_SPACE(dev);
        struct neighbour *neigh;
        bool is_v6gw = false;

        if (dev_xmit_recursion()) {
                net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
                goto out_drop;
        }

        skb->dev = dev;
        skb_clear_tstamp(skb);

        if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
                skb = skb_expand_head(skb, hh_len);
                if (!skb)
                        return -ENOMEM;
        }

        rcu_read_lock();
        if (!nh) {
                struct rtable *rt = skb_rtable(skb);

                neigh = ip_neigh_for_gw(rt, skb, &is_v6gw);
        } else if (nh->nh_family == AF_INET6) {
                if (unlikely(!ipv6_mod_enabled())) {
                        rcu_read_unlock();
                        goto out_drop;
                }
                neigh = ip_neigh_gw6(dev, &nh->ipv6_nh);
                is_v6gw = true;
        } else if (nh->nh_family == AF_INET) {
                neigh = ip_neigh_gw4(dev, nh->ipv4_nh);
        } else {
                rcu_read_unlock();
                goto out_drop;
        }

        if (likely(!IS_ERR(neigh))) {
                int ret;

                sock_confirm_neigh(skb, neigh);
                local_bh_disable();
                dev_xmit_recursion_inc();
                ret = neigh_output(neigh, skb, is_v6gw);
                dev_xmit_recursion_dec();
                local_bh_enable();
                rcu_read_unlock();
                return ret;
        }
        rcu_read_unlock();
out_drop:
        kfree_skb(skb);
        return -ENETDOWN;
}

static int __bpf_redirect_neigh_v4(struct sk_buff *skb, struct net_device *dev,
                                   struct bpf_nh_params *nh)
{
        const struct iphdr *ip4h = ip_hdr(skb);
        struct net *net = dev_net(dev);
        int err, ret = NET_XMIT_DROP;

        if (!nh) {
                struct flowi4 fl4 = {
                        .flowi4_flags = FLOWI_FLAG_ANYSRC,
                        .flowi4_mark  = skb->mark,
                        .flowi4_dscp  = ip4h_dscp(ip4h),
                        .flowi4_oif   = dev->ifindex,
                        .flowi4_proto = ip4h->protocol,
                        .daddr        = ip4h->daddr,
                        .saddr        = ip4h->saddr,
                };
                struct rtable *rt;

                rt = ip_route_output_flow(net, &fl4, NULL);
                if (IS_ERR(rt))
                        goto out_drop;
                if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) {
                        ip_rt_put(rt);
                        goto out_drop;
                }

                skb_dst_drop(skb);
                skb_dst_set(skb, &rt->dst);
        }

        err = bpf_out_neigh_v4(net, skb, dev, nh);
        if (unlikely(net_xmit_eval(err)))
                dev_core_stats_tx_dropped_inc(dev);
        else
                ret = NET_XMIT_SUCCESS;
        goto out_xmit;
out_drop:
        dev_core_stats_tx_dropped_inc(dev);
        kfree_skb(skb);
out_xmit:
        return ret;
}
#else
static int __bpf_redirect_neigh_v4(struct sk_buff *skb, struct net_device *dev,
                                   struct bpf_nh_params *nh)
{
        kfree_skb(skb);
        return NET_XMIT_DROP;
}
#endif /* CONFIG_INET */

static int __bpf_redirect_neigh(struct sk_buff *skb, struct net_device *dev,
                                struct bpf_nh_params *nh)
{
        struct ethhdr *ethh = eth_hdr(skb);

        if (unlikely(skb->mac_header >= skb->network_header))
                goto out;
        bpf_push_mac_rcsum(skb);
        if (is_multicast_ether_addr(ethh->h_dest))
                goto out;

        skb_pull(skb, sizeof(*ethh));
        skb_unset_mac_header(skb);
        skb_reset_network_header(skb);

        if (skb->protocol == htons(ETH_P_IP))
                return __bpf_redirect_neigh_v4(skb, dev, nh);
        else if (skb->protocol == htons(ETH_P_IPV6))
                return __bpf_redirect_neigh_v6(skb, dev, nh);
out:
        kfree_skb(skb);
        return -ENOTSUPP;
}

/* Internal, non-exposed redirect flags. */
enum {
        BPF_F_NEIGH     = (1ULL << 16),
        BPF_F_PEER      = (1ULL << 17),
        BPF_F_NEXTHOP   = (1ULL << 18),
#define BPF_F_REDIRECT_INTERNAL (BPF_F_NEIGH | BPF_F_PEER | BPF_F_NEXTHOP)
};

BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags)
{
        struct net_device *dev;
        struct sk_buff *clone;
        int ret;

        BUILD_BUG_ON(BPF_F_REDIRECT_INTERNAL & BPF_F_REDIRECT_FLAGS);

        if (unlikely(flags & (~(BPF_F_INGRESS) | BPF_F_REDIRECT_INTERNAL)))
                return -EINVAL;

        /* BPF test infra's convert___skb_to_skb() can create type-less
         * GSO packets. gso_features_check() will detect this as a bad
         * offload. However, lets not leak them out in the first place.
         */
        if (unlikely(skb_is_gso(skb) && !skb_shinfo(skb)->gso_type))
                return -EBADMSG;

        dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex);
        if (unlikely(!dev))
                return -EINVAL;

        clone = skb_clone(skb, GFP_ATOMIC);
        if (unlikely(!clone))
                return -ENOMEM;

        /* For direct write, we need to keep the invariant that the skbs
         * we're dealing with need to be uncloned. Should uncloning fail
         * here, we need to free the just generated clone to unclone once
         * again.
         */
        ret = bpf_try_make_head_writable(skb);
        if (unlikely(ret)) {
                kfree_skb(clone);
                return -ENOMEM;
        }

        return __bpf_redirect(clone, dev, flags);
}

static const struct bpf_func_proto bpf_clone_redirect_proto = {
        .func           = bpf_clone_redirect,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
};

static struct net_device *skb_get_peer_dev(struct net_device *dev)
{
        const struct net_device_ops *ops = dev->netdev_ops;

        if (likely(ops->ndo_get_peer_dev))
                return INDIRECT_CALL_1(ops->ndo_get_peer_dev,
                                       netkit_peer_dev, dev);
        return NULL;
}

int skb_do_redirect(struct sk_buff *skb)
{
        struct bpf_redirect_info *ri = bpf_net_ctx_get_ri();
        struct net *net = dev_net(skb->dev);
        struct net_device *dev;
        u32 flags = ri->flags;

        dev = dev_get_by_index_rcu(net, ri->tgt_index);
        ri->tgt_index = 0;
        ri->flags = 0;
        if (unlikely(!dev))
                goto out_drop;
        if (flags & BPF_F_PEER) {
                if (unlikely(!skb_at_tc_ingress(skb)))
                        goto out_drop;
                dev = skb_get_peer_dev(dev);
                if (unlikely(!dev ||
                             !(dev->flags & IFF_UP) ||
                             net_eq(net, dev_net(dev))))
                        goto out_drop;
                skb->dev = dev;
                dev_sw_netstats_rx_add(dev, skb->len);
                skb_scrub_packet(skb, false);
                return -EAGAIN;
        }
        return flags & BPF_F_NEIGH ?
               __bpf_redirect_neigh(skb, dev, flags & BPF_F_NEXTHOP ?
                                    &ri->nh : NULL) :
               __bpf_redirect(skb, dev, flags);
out_drop:
        kfree_skb(skb);
        return -EINVAL;
}

BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags)
{
        struct bpf_redirect_info *ri;

        if (unlikely(!bpf_net_ctx_get() ||
                     (flags & (~(BPF_F_INGRESS) | BPF_F_REDIRECT_INTERNAL))))
                return TC_ACT_SHOT;

        ri = bpf_net_ctx_get_ri();
        ri->flags = flags;
        ri->tgt_index = ifindex;

        return TC_ACT_REDIRECT;
}

static const struct bpf_func_proto bpf_redirect_proto = {
        .func           = bpf_redirect,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_ANYTHING,
        .arg2_type      = ARG_ANYTHING,
};

BPF_CALL_2(bpf_redirect_peer, u32, ifindex, u64, flags)
{
        struct bpf_redirect_info *ri;

        if (unlikely(!bpf_net_ctx_get() || flags))
                return TC_ACT_SHOT;

        ri = bpf_net_ctx_get_ri();
        ri->flags = BPF_F_PEER;
        ri->tgt_index = ifindex;

        return TC_ACT_REDIRECT;
}

static const struct bpf_func_proto bpf_redirect_peer_proto = {
        .func           = bpf_redirect_peer,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_ANYTHING,
        .arg2_type      = ARG_ANYTHING,
};

BPF_CALL_4(bpf_redirect_neigh, u32, ifindex, struct bpf_redir_neigh *, params,
           int, plen, u64, flags)
{
        struct bpf_redirect_info *ri;

        if (unlikely((plen && plen < sizeof(*params)) ||
                     !bpf_net_ctx_get() || flags))
                return TC_ACT_SHOT;

        ri = bpf_net_ctx_get_ri();
        ri->flags = BPF_F_NEIGH | (plen ? BPF_F_NEXTHOP : 0);
        ri->tgt_index = ifindex;

        BUILD_BUG_ON(sizeof(struct bpf_redir_neigh) != sizeof(struct bpf_nh_params));
        if (plen)
                memcpy(&ri->nh, params, sizeof(ri->nh));

        return TC_ACT_REDIRECT;
}

static const struct bpf_func_proto bpf_redirect_neigh_proto = {
        .func           = bpf_redirect_neigh,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_ANYTHING,
        .arg2_type      = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
        .arg4_type      = ARG_ANYTHING,
};

BPF_CALL_2(bpf_msg_apply_bytes, struct sk_msg *, msg, u32, bytes)
{
        msg->apply_bytes = bytes;
        return 0;
}

static const struct bpf_func_proto bpf_msg_apply_bytes_proto = {
        .func           = bpf_msg_apply_bytes,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
};

BPF_CALL_2(bpf_msg_cork_bytes, struct sk_msg *, msg, u32, bytes)
{
        msg->cork_bytes = bytes;
        return 0;
}

static void sk_msg_reset_curr(struct sk_msg *msg)
{
        if (!msg->sg.size) {
                msg->sg.curr = msg->sg.start;
                msg->sg.copybreak = 0;
        } else {
                u32 i = msg->sg.end;

                sk_msg_iter_var_prev(i);
                msg->sg.curr = i;
                msg->sg.copybreak = msg->sg.data[i].length;
        }
}

static bool sk_msg_elem_is_copy(const struct sk_msg *msg, u32 i)
{
        return test_bit(i, msg->sg.copy);
}

static void sk_msg_clear_elem_copy(struct sk_msg *msg, u32 i)
{
        __clear_bit(i, msg->sg.copy);
}

static void sk_msg_set_elem_copy(struct sk_msg *msg, u32 i, bool sg_copy)
{
        __assign_bit(i, msg->sg.copy, sg_copy);
}

static void sk_msg_clear_copy_range(struct sk_msg *msg, u32 start, u32 end)
{
        while (start != end) {
                sk_msg_clear_elem_copy(msg, start);
                sk_msg_iter_var_next(start);
        }
}

static void sk_msg_sg_move(struct sk_msg *msg, u32 dst, u32 src)
{
        msg->sg.data[dst] = msg->sg.data[src];

        sk_msg_set_elem_copy(msg, dst,  
                sk_msg_elem_is_copy(msg, src));
}

static const struct bpf_func_proto bpf_msg_cork_bytes_proto = {
        .func           = bpf_msg_cork_bytes,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
};

BPF_CALL_4(bpf_msg_pull_data, struct sk_msg *, msg, u32, start,
           u32, end, u64, flags)
{
        u32 len = 0, offset = 0, copy = 0, poffset = 0, bytes = end - start;
        u32 first_sge, last_sge, i, shift, bytes_sg_total;
        struct scatterlist *sge;
        u8 *raw, *to, *from;
        struct page *page;

        if (unlikely(flags || end <= start))
                return -EINVAL;

        /* First find the starting scatterlist element */
        i = msg->sg.start;
        do {
                offset += len;
                len = sk_msg_elem(msg, i)->length;
                if (start < offset + len)
                        break;
                sk_msg_iter_var_next(i);
        } while (i != msg->sg.end);

        if (unlikely(start >= offset + len))
                return -EINVAL;

        first_sge = i;
        /* The start may point into the sg element so we need to also
         * account for the headroom.
         */
        bytes_sg_total = start - offset + bytes;
        if (!sk_msg_elem_is_copy(msg, i) && bytes_sg_total <= len)
                goto out;

        /* At this point we need to linearize multiple scatterlist
         * elements or a single shared page. Either way we need to
         * copy into a linear buffer exclusively owned by BPF. Then
         * place the buffer in the scatterlist and fixup the original
         * entries by removing the entries now in the linear buffer
         * and shifting the remaining entries. For now we do not try
         * to copy partial entries to avoid complexity of running out
         * of sg_entry slots. The downside is reading a single byte
         * will copy the entire sg entry.
         */
        do {
                copy += sk_msg_elem(msg, i)->length;
                sk_msg_iter_var_next(i);
                if (bytes_sg_total <= copy)
                        break;
        } while (i != msg->sg.end);
        last_sge = i;

        if (unlikely(bytes_sg_total > copy))
                return -EINVAL;

        page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC | __GFP_COMP,
                           get_order(copy));
        if (unlikely(!page))
                return -ENOMEM;

        raw = page_address(page);
        i = first_sge;
        do {
                sge = sk_msg_elem(msg, i);
                from = sg_virt(sge);
                len = sge->length;
                to = raw + poffset;

                memcpy(to, from, len);
                poffset += len;
                sge->length = 0;
                put_page(sg_page(sge));
                sk_msg_clear_elem_copy(msg, i);

                sk_msg_iter_var_next(i);
        } while (i != last_sge);

        sg_set_page(&msg->sg.data[first_sge], page, copy, 0);
        sk_msg_clear_elem_copy(msg, first_sge);

        /* To repair sg ring we need to shift entries. If we only
         * had a single entry though we can just replace it and
         * be done. Otherwise walk the ring and shift the entries.
         */
        WARN_ON_ONCE(last_sge == first_sge);
        shift = last_sge > first_sge ?
                last_sge - first_sge - 1 :
                NR_MSG_FRAG_IDS - first_sge + last_sge - 1;
        if (!shift) {
                sk_msg_clear_elem_copy(msg, msg->sg.end);
                goto out;
        }

        i = first_sge;
        sk_msg_iter_var_next(i);
        sk_msg_clear_copy_range(msg, i, last_sge);

        i = first_sge;
        sk_msg_iter_var_next(i);
        do {
                u32 move_from;

                if (i + shift >= NR_MSG_FRAG_IDS)
                        move_from = i + shift - NR_MSG_FRAG_IDS;
                else
                        move_from = i + shift;
                if (move_from == msg->sg.end)
                        break;

                sk_msg_sg_move(msg, i, move_from);
                msg->sg.data[move_from].length = 0;
                msg->sg.data[move_from].page_link = 0;
                msg->sg.data[move_from].offset = 0;
                sk_msg_clear_elem_copy(msg, move_from);
                sk_msg_iter_var_next(i);
        } while (1);

        msg->sg.end = msg->sg.end - shift > msg->sg.end ?
                      msg->sg.end - shift + NR_MSG_FRAG_IDS :
                      msg->sg.end - shift;
        sk_msg_clear_elem_copy(msg, msg->sg.end);
out:
        sk_msg_reset_curr(msg);
        msg->data = sg_virt(&msg->sg.data[first_sge]) + start - offset;
        msg->data_end = msg->data + bytes;
        return 0;
}

static const struct bpf_func_proto bpf_msg_pull_data_proto = {
        .func           = bpf_msg_pull_data,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_ANYTHING,
};

BPF_CALL_4(bpf_msg_push_data, struct sk_msg *, msg, u32, start,
           u32, len, u64, flags)
{
        bool sge_copy = false, nsge_copy = false, nnsge_copy = false;
        struct scatterlist sge, nsge, nnsge, rsge = {0}, *psge;
        u32 new, i = 0, l = 0, space, copy = 0, offset = 0;
        bool rsge_copy = false;
        u8 *raw, *to, *from;
        struct page *page;

        if (unlikely(flags))
                return -EINVAL;

        if (unlikely(len == 0))
                return 0;

        /* First find the starting scatterlist element */
        i = msg->sg.start;
        do {
                offset += l;
                l = sk_msg_elem(msg, i)->length;

                if (start < offset + l)
                        break;
                sk_msg_iter_var_next(i);
        } while (i != msg->sg.end);

        if (start > offset + l)
                return -EINVAL;

        space = MAX_MSG_FRAGS - sk_msg_elem_used(msg);

        /* If no space available will fallback to copy, we need at
         * least one scatterlist elem available to push data into
         * when start aligns to the beginning of an element or two
         * when it falls inside an element. We handle the start equals
         * offset case because its the common case for inserting a
         * header.
         */
        if (!space || (space == 1 && start != offset))
                copy = msg->sg.data[i].length;

        if (unlikely(copy + len < copy))
                return -EINVAL;

        page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC | __GFP_COMP,
                           get_order(copy + len));
        if (unlikely(!page))
                return -ENOMEM;

        if (copy) {
                int front, back;

                raw = page_address(page);

                if (i == msg->sg.end)
                        sk_msg_iter_var_prev(i);
                psge = sk_msg_elem(msg, i);
                front = start - offset;
                back = psge->length - front;
                from = sg_virt(psge);

                if (front)
                        memcpy(raw, from, front);

                if (back) {
                        from += front;
                        to = raw + front + len;

                        memcpy(to, from, back);
                }

                put_page(sg_page(psge));
                new = i;
                goto place_new;
        }

        if (start - offset) {
                if (i == msg->sg.end)
                        sk_msg_iter_var_prev(i);
                psge = sk_msg_elem(msg, i);
                rsge = sk_msg_elem_cpy(msg, i);
                rsge_copy = sk_msg_elem_is_copy(msg, i);

                psge->length = start - offset;
                rsge.length -= psge->length;
                rsge.offset += start - offset;

                sk_msg_iter_var_next(i);
                sg_unmark_end(psge);
                sg_unmark_end(&rsge);
        }

        /* Slot(s) to place newly allocated data */
        sk_msg_iter_next(msg, end);
        new = i;
        sk_msg_iter_var_next(i);

        if (i == msg->sg.end) {
                if (!rsge.length)
                        goto place_new;
                sk_msg_iter_next(msg, end);
                goto place_new;
        }

        /* Shift one or two slots as needed */
        sge = sk_msg_elem_cpy(msg, new);
        sg_unmark_end(&sge);
        sge_copy = sk_msg_elem_is_copy(msg, new);

        nsge = sk_msg_elem_cpy(msg, i);
        nsge_copy = sk_msg_elem_is_copy(msg, i);
        if (rsge.length) {
                sk_msg_iter_var_next(i);
                nnsge = sk_msg_elem_cpy(msg, i);
                nnsge_copy = sk_msg_elem_is_copy(msg, i);
                sk_msg_iter_next(msg, end);
        }

        while (i != msg->sg.end) {
                msg->sg.data[i] = sge;
                sk_msg_set_elem_copy(msg, i, sge_copy);
                sge = nsge;
                sge_copy = nsge_copy;
                sk_msg_iter_var_next(i);
                if (rsge.length) {
                        nsge = nnsge;
                        nsge_copy = nnsge_copy;
                        nnsge = sk_msg_elem_cpy(msg, i);
                        nnsge_copy = sk_msg_elem_is_copy(msg, i);
                } else {
                        nsge = sk_msg_elem_cpy(msg, i);
                        nsge_copy = sk_msg_elem_is_copy(msg, i);
                }
        }

place_new:
        /* Place newly allocated data buffer */
        sk_mem_charge(msg->sk, len);
        msg->sg.size += len;
        sk_msg_clear_elem_copy(msg, new);
        sg_set_page(&msg->sg.data[new], page, len + copy, 0);
        if (rsge.length) {
                get_page(sg_page(&rsge));
                sk_msg_iter_var_next(new);
                msg->sg.data[new] = rsge;
                sk_msg_set_elem_copy(msg, new, rsge_copy);
        }
        sk_msg_clear_elem_copy(msg, msg->sg.end);

        sk_msg_reset_curr(msg);
        sk_msg_compute_data_pointers(msg);
        return 0;
}

static const struct bpf_func_proto bpf_msg_push_data_proto = {
        .func           = bpf_msg_push_data,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_ANYTHING,
};

static void sk_msg_shift_left(struct sk_msg *msg, int i)
{
        struct scatterlist *sge = sk_msg_elem(msg, i);
        int prev;

        put_page(sg_page(sge));
        do {
                prev = i;
                sk_msg_iter_var_next(i);
                sk_msg_sg_move(msg, prev, i);
        } while (i != msg->sg.end);

        sk_msg_iter_prev(msg, end);
        sk_msg_clear_elem_copy(msg, msg->sg.end);
}

static void sk_msg_shift_right(struct sk_msg *msg, int i)
{
        struct scatterlist tmp, sge;
        bool tmp_copy, sge_copy;

        sk_msg_iter_next(msg, end);
        sge = sk_msg_elem_cpy(msg, i);
        sge_copy = sk_msg_elem_is_copy(msg, i);
        sk_msg_iter_var_next(i);
        tmp = sk_msg_elem_cpy(msg, i);
        tmp_copy = sk_msg_elem_is_copy(msg, i);

        while (i != msg->sg.end) {
                msg->sg.data[i] = sge;
                sk_msg_set_elem_copy(msg, i, sge_copy);
                sk_msg_iter_var_next(i);
                sge = tmp;
                sge_copy = tmp_copy;
                tmp = sk_msg_elem_cpy(msg, i);
                tmp_copy = sk_msg_elem_is_copy(msg, i);
        }
        sk_msg_clear_elem_copy(msg, msg->sg.end);
}

BPF_CALL_4(bpf_msg_pop_data, struct sk_msg *, msg, u32, start,
           u32, len, u64, flags)
{
        u32 i = 0, l = 0, space, offset = 0;
        u64 last = (u64)start + len;
        u32 pop;

        if (unlikely(flags))
                return -EINVAL;

        if (unlikely(len == 0))
                return 0;

        /* First find the starting scatterlist element */
        i = msg->sg.start;
        do {
                offset += l;
                l = sk_msg_elem(msg, i)->length;

                if (start < offset + l)
                        break;
                sk_msg_iter_var_next(i);
        } while (i != msg->sg.end);

        /* Bounds checks: start and pop must be inside message */
        if (start >= offset + l || last > msg->sg.size)
                return -EINVAL;

        space = MAX_MSG_FRAGS - sk_msg_elem_used(msg);

        pop = len;
        /* --------------| offset
         * -| start      |-------- len -------|
         *
         *  |----- a ----|-------- pop -------|----- b ----|
         *  |______________________________________________| length
         *
         *
         * a:   region at front of scatter element to save
         * b:   region at back of scatter element to save when length > A + pop
         * pop: region to pop from element, same as input 'pop' here will be
         *      decremented below per iteration.
         *
         * Two top-level cases to handle when start != offset, first B is non
         * zero and second B is zero corresponding to when a pop includes more
         * than one element.
         *
         * Then if B is non-zero AND there is no space allocate space and
         * compact A, B regions into page. If there is space shift ring to
         * the right free'ing the next element in ring to place B, leaving
         * A untouched except to reduce length.
         */
        if (start != offset) {
                struct scatterlist *nsge, *sge = sk_msg_elem(msg, i);
                bool sge_copy = sk_msg_elem_is_copy(msg, i);
                int a = start - offset;
                int b = sge->length - pop - a;
                u32 sge_idx = i;

                sk_msg_iter_var_next(i);

                if (b > 0) {
                        if (space) {
                                sge->length = a;
                                sk_msg_shift_right(msg, i);
                                nsge = sk_msg_elem(msg, i);
                                get_page(sg_page(sge));
                                sg_set_page(nsge,
                                            sg_page(sge),
                                            b, sge->offset + pop + a);
                                sk_msg_set_elem_copy(msg, i, sge_copy);
                        } else {
                                struct page *page, *orig;
                                u8 *to, *from;

                                page = alloc_pages(__GFP_NOWARN |
                                                   __GFP_COMP   | GFP_ATOMIC,
                                                   get_order(a + b));
                                if (unlikely(!page))
                                        return -ENOMEM;

                                orig = sg_page(sge);
                                from = sg_virt(sge);
                                to = page_address(page);
                                memcpy(to, from, a);
                                memcpy(to + a, from + a + pop, b);
                                sg_set_page(sge, page, a + b, 0);
                                sk_msg_clear_elem_copy(msg, sge_idx);
                                put_page(orig);
                        }
                        pop = 0;
                } else {
                        pop -= (sge->length - a);
                        sge->length = a;
                }
        }

        /* From above the current layout _must_ be as follows,
         *
         * -| offset
         * -| start
         *
         *  |---- pop ---|---------------- b ------------|
         *  |____________________________________________| length
         *
         * Offset and start of the current msg elem are equal because in the
         * previous case we handled offset != start and either consumed the
         * entire element and advanced to the next element OR pop == 0.
         *
         * Two cases to handle here are first pop is less than the length
         * leaving some remainder b above. Simply adjust the element's layout
         * in this case. Or pop >= length of the element so that b = 0. In this
         * case advance to next element decrementing pop.
         */
        while (pop) {
                struct scatterlist *sge = sk_msg_elem(msg, i);

                if (pop < sge->length) {
                        sge->length -= pop;
                        sge->offset += pop;
                        pop = 0;
                } else {
                        pop -= sge->length;
                        sk_msg_shift_left(msg, i);
                }
        }

        sk_mem_uncharge(msg->sk, len - pop);
        msg->sg.size -= (len - pop);
        sk_msg_reset_curr(msg);
        sk_msg_compute_data_pointers(msg);
        return 0;
}

static const struct bpf_func_proto bpf_msg_pop_data_proto = {
        .func           = bpf_msg_pop_data,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_ANYTHING,
};

#ifdef CONFIG_CGROUP_NET_CLASSID
BPF_CALL_0(bpf_get_cgroup_classid_curr)
{
        return __task_get_classid(current);
}

const struct bpf_func_proto bpf_get_cgroup_classid_curr_proto = {
        .func           = bpf_get_cgroup_classid_curr,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
};

BPF_CALL_1(bpf_skb_cgroup_classid, const struct sk_buff *, skb)
{
        struct sock *sk = skb_to_full_sk(skb);

        if (!sk || !sk_fullsock(sk))
                return 0;

        return sock_cgroup_classid(&sk->sk_cgrp_data);
}

static const struct bpf_func_proto bpf_skb_cgroup_classid_proto = {
        .func           = bpf_skb_cgroup_classid,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
};
#endif

BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb)
{
        return task_get_classid(skb);
}

static const struct bpf_func_proto bpf_get_cgroup_classid_proto = {
        .func           = bpf_get_cgroup_classid,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
};

BPF_CALL_1(bpf_get_route_realm, const struct sk_buff *, skb)
{
        return dst_tclassid(skb);
}

static const struct bpf_func_proto bpf_get_route_realm_proto = {
        .func           = bpf_get_route_realm,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
};

BPF_CALL_1(bpf_get_hash_recalc, struct sk_buff *, skb)
{
        /* If skb_clear_hash() was called due to mangling, we can
         * trigger SW recalculation here. Later access to hash
         * can then use the inline skb->hash via context directly
         * instead of calling this helper again.
         */
        return skb_get_hash(skb);
}

static const struct bpf_func_proto bpf_get_hash_recalc_proto = {
        .func           = bpf_get_hash_recalc,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
};

BPF_CALL_1(bpf_set_hash_invalid, struct sk_buff *, skb)
{
        /* After all direct packet write, this can be used once for
         * triggering a lazy recalc on next skb_get_hash() invocation.
         */
        skb_clear_hash(skb);
        return 0;
}

static const struct bpf_func_proto bpf_set_hash_invalid_proto = {
        .func           = bpf_set_hash_invalid,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
};

BPF_CALL_2(bpf_set_hash, struct sk_buff *, skb, u32, hash)
{
        /* Set user specified hash as L4(+), so that it gets returned
         * on skb_get_hash() call unless BPF prog later on triggers a
         * skb_clear_hash().
         */
        __skb_set_sw_hash(skb, hash, true);
        return 0;
}

static const struct bpf_func_proto bpf_set_hash_proto = {
        .func           = bpf_set_hash,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
};

BPF_CALL_3(bpf_skb_vlan_push, struct sk_buff *, skb, __be16, vlan_proto,
           u16, vlan_tci)
{
        int ret;

        if (unlikely(vlan_proto != htons(ETH_P_8021Q) &&
                     vlan_proto != htons(ETH_P_8021AD)))
                vlan_proto = htons(ETH_P_8021Q);

        bpf_push_mac_rcsum(skb);
        ret = skb_vlan_push(skb, vlan_proto, vlan_tci);
        bpf_pull_mac_rcsum(skb);
        skb_reset_mac_len(skb);

        bpf_compute_data_pointers(skb);
        return ret;
}

static const struct bpf_func_proto bpf_skb_vlan_push_proto = {
        .func           = bpf_skb_vlan_push,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
};

BPF_CALL_1(bpf_skb_vlan_pop, struct sk_buff *, skb)
{
        int ret;

        bpf_push_mac_rcsum(skb);
        ret = skb_vlan_pop(skb);
        bpf_pull_mac_rcsum(skb);

        bpf_compute_data_pointers(skb);
        return ret;
}

static const struct bpf_func_proto bpf_skb_vlan_pop_proto = {
        .func           = bpf_skb_vlan_pop,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
};

static int bpf_skb_generic_push(struct sk_buff *skb, u32 off, u32 len)
{
        /* Caller already did skb_cow() with meta_len+len as headroom,
         * so no need to do it here.
         */
        skb_push(skb, len);
        skb_postpush_data_move(skb, len, off);
        memset(skb->data + off, 0, len);

        /* No skb_postpush_rcsum(skb, skb->data + off, len)
         * needed here as it does not change the skb->csum
         * result for checksum complete when summing over
         * zeroed blocks.
         */
        return 0;
}

static int bpf_skb_generic_pop(struct sk_buff *skb, u32 off, u32 len)
{
        void *old_data;

        /* skb_ensure_writable() is not needed here, as we're
         * already working on an uncloned skb.
         */
        if (unlikely(!pskb_may_pull(skb, off + len)))
                return -ENOMEM;

        old_data = skb->data;
        __skb_pull(skb, len);
        skb_postpull_rcsum(skb, old_data + off, len);
        skb_postpull_data_move(skb, len, off);

        return 0;
}

static int bpf_skb_net_hdr_push(struct sk_buff *skb, u32 off, u32 len)
{
        bool trans_same = skb->transport_header == skb->network_header;
        int ret;

        /* There's no need for __skb_push()/__skb_pull() pair to
         * get to the start of the mac header as we're guaranteed
         * to always start from here under eBPF.
         */
        ret = bpf_skb_generic_push(skb, off, len);
        if (likely(!ret)) {
                skb->mac_header -= len;
                skb->network_header -= len;
                if (trans_same)
                        skb->transport_header = skb->network_header;
        }

        return ret;
}

static int bpf_skb_net_hdr_pop(struct sk_buff *skb, u32 off, u32 len)
{
        bool trans_same = skb->transport_header == skb->network_header;
        int ret;

        /* Same here, __skb_push()/__skb_pull() pair not needed. */
        ret = bpf_skb_generic_pop(skb, off, len);
        if (likely(!ret)) {
                skb->mac_header += len;
                skb->network_header += len;
                if (trans_same)
                        skb->transport_header = skb->network_header;
        }

        return ret;
}

static int bpf_skb_proto_4_to_6(struct sk_buff *skb)
{
        const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
        const u8 meta_len = skb_metadata_len(skb);
        u32 off = skb_mac_header_len(skb);
        int ret;

        ret = skb_cow(skb, meta_len + len_diff);
        if (unlikely(ret < 0))
                return ret;

        ret = bpf_skb_net_hdr_push(skb, off, len_diff);
        if (unlikely(ret < 0))
                return ret;

        if (skb_is_gso(skb)) {
                struct skb_shared_info *shinfo = skb_shinfo(skb);

                /* SKB_GSO_TCPV4 needs to be changed into SKB_GSO_TCPV6. */
                if (shinfo->gso_type & SKB_GSO_TCPV4) {
                        shinfo->gso_type &= ~SKB_GSO_TCPV4;
                        shinfo->gso_type |=  SKB_GSO_TCPV6;
                }
                shinfo->gso_type |=  SKB_GSO_DODGY;
        }

        skb->protocol = htons(ETH_P_IPV6);
        skb_clear_hash(skb);

        return 0;
}

static int bpf_skb_proto_6_to_4(struct sk_buff *skb)
{
        const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
        u32 off = skb_mac_header_len(skb);
        int ret;

        ret = skb_unclone(skb, GFP_ATOMIC);
        if (unlikely(ret < 0))
                return ret;

        ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
        if (unlikely(ret < 0))
                return ret;

        if (skb_is_gso(skb)) {
                struct skb_shared_info *shinfo = skb_shinfo(skb);

                /* SKB_GSO_TCPV6 needs to be changed into SKB_GSO_TCPV4. */
                if (shinfo->gso_type & SKB_GSO_TCPV6) {
                        shinfo->gso_type &= ~SKB_GSO_TCPV6;
                        shinfo->gso_type |=  SKB_GSO_TCPV4;
                }
                shinfo->gso_type |=  SKB_GSO_DODGY;
        }

        skb->protocol = htons(ETH_P_IP);
        skb_clear_hash(skb);

        return 0;
}

static int bpf_skb_proto_xlat(struct sk_buff *skb, __be16 to_proto)
{
        __be16 from_proto = skb->protocol;

        if (from_proto == htons(ETH_P_IP) &&
              to_proto == htons(ETH_P_IPV6))
                return bpf_skb_proto_4_to_6(skb);

        if (from_proto == htons(ETH_P_IPV6) &&
              to_proto == htons(ETH_P_IP))
                return bpf_skb_proto_6_to_4(skb);

        return -ENOTSUPP;
}

BPF_CALL_3(bpf_skb_change_proto, struct sk_buff *, skb, __be16, proto,
           u64, flags)
{
        int ret;

        if (unlikely(flags))
                return -EINVAL;

        /* General idea is that this helper does the basic groundwork
         * needed for changing the protocol, and eBPF program fills the
         * rest through bpf_skb_store_bytes(), bpf_lX_csum_replace()
         * and other helpers, rather than passing a raw buffer here.
         *
         * The rationale is to keep this minimal and without a need to
         * deal with raw packet data. F.e. even if we would pass buffers
         * here, the program still needs to call the bpf_lX_csum_replace()
         * helpers anyway. Plus, this way we keep also separation of
         * concerns, since f.e. bpf_skb_store_bytes() should only take
         * care of stores.
         *
         * Currently, additional options and extension header space are
         * not supported, but flags register is reserved so we can adapt
         * that. For offloads, we mark packet as dodgy, so that headers
         * need to be verified first.
         */
        ret = bpf_skb_proto_xlat(skb, proto);
        bpf_compute_data_pointers(skb);
        if (ret)
                return ret;

        if (skb_valid_dst(skb))
                skb_dst_drop(skb);

        return 0;
}

static const struct bpf_func_proto bpf_skb_change_proto_proto = {
        .func           = bpf_skb_change_proto,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
};

BPF_CALL_2(bpf_skb_change_type, struct sk_buff *, skb, u32, pkt_type)
{
        /* We only allow a restricted subset to be changed for now. */
        if (unlikely(!skb_pkt_type_ok(skb->pkt_type) ||
                     !skb_pkt_type_ok(pkt_type)))
                return -EINVAL;

        skb->pkt_type = pkt_type;
        return 0;
}

static const struct bpf_func_proto bpf_skb_change_type_proto = {
        .func           = bpf_skb_change_type,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
};

static u32 bpf_skb_net_base_len(const struct sk_buff *skb)
{
        switch (skb->protocol) {
        case htons(ETH_P_IP):
                return sizeof(struct iphdr);
        case htons(ETH_P_IPV6):
                return sizeof(struct ipv6hdr);
        default:
                return ~0U;
        }
}

#define BPF_F_ADJ_ROOM_ENCAP_L3_MASK    (BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 | \
                                         BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)

#define BPF_F_ADJ_ROOM_DECAP_L3_MASK    (BPF_F_ADJ_ROOM_DECAP_L3_IPV4 | \
                                         BPF_F_ADJ_ROOM_DECAP_L3_IPV6)

#define BPF_F_ADJ_ROOM_MASK             (BPF_F_ADJ_ROOM_FIXED_GSO | \
                                         BPF_F_ADJ_ROOM_ENCAP_L3_MASK | \
                                         BPF_F_ADJ_ROOM_ENCAP_L4_GRE | \
                                         BPF_F_ADJ_ROOM_ENCAP_L4_UDP | \
                                         BPF_F_ADJ_ROOM_ENCAP_L2_ETH | \
                                         BPF_F_ADJ_ROOM_ENCAP_L2( \
                                          BPF_ADJ_ROOM_ENCAP_L2_MASK) | \
                                         BPF_F_ADJ_ROOM_DECAP_L3_MASK)

static int bpf_skb_net_grow(struct sk_buff *skb, u32 off, u32 len_diff,
                            u64 flags)
{
        u8 inner_mac_len = flags >> BPF_ADJ_ROOM_ENCAP_L2_SHIFT;
        bool encap = flags & BPF_F_ADJ_ROOM_ENCAP_L3_MASK;
        u16 mac_len = 0, inner_net = 0, inner_trans = 0;
        const u8 meta_len = skb_metadata_len(skb);
        unsigned int gso_type = SKB_GSO_DODGY;
        int ret;

        if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) {
                /* udp gso_size delineates datagrams, only allow if fixed */
                if (!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) ||
                    !(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
                        return -ENOTSUPP;
        }

        ret = skb_cow_head(skb, meta_len + len_diff);
        if (unlikely(ret < 0))
                return ret;

        if (encap) {
                if (skb->protocol != htons(ETH_P_IP) &&
                    skb->protocol != htons(ETH_P_IPV6))
                        return -ENOTSUPP;

                if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 &&
                    flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
                        return -EINVAL;

                if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE &&
                    flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP)
                        return -EINVAL;

                if (flags & BPF_F_ADJ_ROOM_ENCAP_L2_ETH &&
                    inner_mac_len < ETH_HLEN)
                        return -EINVAL;

                if (skb->encapsulation)
                        return -EALREADY;

                mac_len = skb->network_header - skb->mac_header;
                inner_net = skb->network_header;
                if (inner_mac_len > len_diff)
                        return -EINVAL;
                inner_trans = skb->transport_header;
        }

        ret = bpf_skb_net_hdr_push(skb, off, len_diff);
        if (unlikely(ret < 0))
                return ret;

        if (encap) {
                skb->inner_mac_header = inner_net - inner_mac_len;
                skb->inner_network_header = inner_net;
                skb->inner_transport_header = inner_trans;

                if (flags & BPF_F_ADJ_ROOM_ENCAP_L2_ETH)
                        skb_set_inner_protocol(skb, htons(ETH_P_TEB));
                else
                        skb_set_inner_protocol(skb, skb->protocol);

                skb->encapsulation = 1;
                skb_set_network_header(skb, mac_len);

                if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP)
                        gso_type |= SKB_GSO_UDP_TUNNEL;
                else if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE)
                        gso_type |= SKB_GSO_GRE;
                else if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
                        gso_type |= SKB_GSO_IPXIP6;
                else if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4)
                        gso_type |= SKB_GSO_IPXIP4;

                if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE ||
                    flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP) {
                        int nh_len = flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6 ?
                                        sizeof(struct ipv6hdr) :
                                        sizeof(struct iphdr);

                        skb_set_transport_header(skb, mac_len + nh_len);
                }

                /* Match skb->protocol to new outer l3 protocol */
                if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
                        skb->protocol = htons(ETH_P_IPV6);
                else if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4)
                        skb->protocol = htons(ETH_P_IP);

                if (skb_valid_dst(skb))
                        skb_dst_drop(skb);
        }

        if (skb_is_gso(skb)) {
                struct skb_shared_info *shinfo = skb_shinfo(skb);

                /* Header must be checked, and gso_segs recomputed. */
                shinfo->gso_type |= gso_type;
                shinfo->gso_segs = 0;

                /* Due to header growth, MSS needs to be downgraded.
                 * There is a BUG_ON() when segmenting the frag_list with
                 * head_frag true, so linearize the skb after downgrading
                 * the MSS.
                 */
                if (!(flags & BPF_F_ADJ_ROOM_FIXED_GSO)) {
                        skb_decrease_gso_size(shinfo, len_diff);
                        if (shinfo->frag_list)
                                return skb_linearize(skb);
                }
        }

        return 0;
}

static int bpf_skb_net_shrink(struct sk_buff *skb, u32 off, u32 len_diff,
                              u64 flags)
{
        bool decap = flags & BPF_F_ADJ_ROOM_DECAP_L3_MASK;
        int ret;

        if (unlikely(flags & ~(BPF_F_ADJ_ROOM_FIXED_GSO |
                               BPF_F_ADJ_ROOM_DECAP_L3_MASK |
                               BPF_F_ADJ_ROOM_NO_CSUM_RESET)))
                return -EINVAL;

        if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) {
                /* udp gso_size delineates datagrams, only allow if fixed */
                if (!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) ||
                    !(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
                        return -ENOTSUPP;
        }

        ret = skb_unclone(skb, GFP_ATOMIC);
        if (unlikely(ret < 0))
                return ret;

        ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
        if (unlikely(ret < 0))
                return ret;

        if (decap) {
                /* Match skb->protocol to new outer l3 protocol */
                if (flags & BPF_F_ADJ_ROOM_DECAP_L3_IPV6)
                        skb->protocol = htons(ETH_P_IPV6);
                else if (flags & BPF_F_ADJ_ROOM_DECAP_L3_IPV4)
                        skb->protocol = htons(ETH_P_IP);

                if (skb_valid_dst(skb))
                        skb_dst_drop(skb);
        }

        if (skb_is_gso(skb)) {
                struct skb_shared_info *shinfo = skb_shinfo(skb);

                /* Due to header shrink, MSS can be upgraded. */
                if (!(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
                        skb_increase_gso_size(shinfo, len_diff);

                /* Header must be checked, and gso_segs recomputed. */
                shinfo->gso_type |= SKB_GSO_DODGY;
                shinfo->gso_segs = 0;
        }

        return 0;
}

#define BPF_SKB_MAX_LEN SKB_MAX_ALLOC

BPF_CALL_4(sk_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
           u32, mode, u64, flags)
{
        u32 len_diff_abs = abs(len_diff);
        bool shrink = len_diff < 0;
        int ret = 0;

        if (unlikely(flags || mode))
                return -EINVAL;
        if (unlikely(len_diff_abs > 0xfffU))
                return -EFAULT;

        if (!shrink) {
                ret = skb_cow(skb, len_diff);
                if (unlikely(ret < 0))
                        return ret;
                __skb_push(skb, len_diff_abs);
                memset(skb->data, 0, len_diff_abs);
        } else {
                if (unlikely(!pskb_may_pull(skb, len_diff_abs)))
                        return -ENOMEM;
                __skb_pull(skb, len_diff_abs);
        }
        if (tls_sw_has_ctx_rx(skb->sk)) {
                struct strp_msg *rxm = strp_msg(skb);

                rxm->full_len += len_diff;
        }
        return ret;
}

static const struct bpf_func_proto sk_skb_adjust_room_proto = {
        .func           = sk_skb_adjust_room,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_ANYTHING,
};

BPF_CALL_4(bpf_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
           u32, mode, u64, flags)
{
        u32 len_cur, len_diff_abs = abs(len_diff);
        u32 len_min = bpf_skb_net_base_len(skb);
        u32 len_max = BPF_SKB_MAX_LEN;
        __be16 proto = skb->protocol;
        bool shrink = len_diff < 0;
        u32 off;
        int ret;

        if (unlikely(flags & ~(BPF_F_ADJ_ROOM_MASK |
                               BPF_F_ADJ_ROOM_NO_CSUM_RESET)))
                return -EINVAL;
        if (unlikely(len_diff_abs > 0xfffU))
                return -EFAULT;
        if (unlikely(proto != htons(ETH_P_IP) &&
                     proto != htons(ETH_P_IPV6)))
                return -ENOTSUPP;

        off = skb_mac_header_len(skb);
        switch (mode) {
        case BPF_ADJ_ROOM_NET:
                off += bpf_skb_net_base_len(skb);
                break;
        case BPF_ADJ_ROOM_MAC:
                break;
        default:
                return -ENOTSUPP;
        }

        if (flags & BPF_F_ADJ_ROOM_DECAP_L3_MASK) {
                if (!shrink)
                        return -EINVAL;

                switch (flags & BPF_F_ADJ_ROOM_DECAP_L3_MASK) {
                case BPF_F_ADJ_ROOM_DECAP_L3_IPV4:
                        len_min = sizeof(struct iphdr);
                        break;
                case BPF_F_ADJ_ROOM_DECAP_L3_IPV6:
                        len_min = sizeof(struct ipv6hdr);
                        break;
                default:
                        return -EINVAL;
                }
        }

        len_cur = skb->len - skb_network_offset(skb);
        if ((shrink && (len_diff_abs >= len_cur ||
                        len_cur - len_diff_abs < len_min)) ||
            (!shrink && (skb->len + len_diff_abs > len_max &&
                         !skb_is_gso(skb))))
                return -ENOTSUPP;

        ret = shrink ? bpf_skb_net_shrink(skb, off, len_diff_abs, flags) :
                       bpf_skb_net_grow(skb, off, len_diff_abs, flags);
        if (!ret && !(flags & BPF_F_ADJ_ROOM_NO_CSUM_RESET))
                __skb_reset_checksum_unnecessary(skb);

        bpf_compute_data_pointers(skb);
        return ret;
}

static const struct bpf_func_proto bpf_skb_adjust_room_proto = {
        .func           = bpf_skb_adjust_room,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_ANYTHING,
};

static u32 __bpf_skb_min_len(const struct sk_buff *skb)
{
        int offset = skb_network_offset(skb);
        u32 min_len = 0;

        if (offset > 0)
                min_len = offset;
        if (skb_transport_header_was_set(skb)) {
                offset = skb_transport_offset(skb);
                if (offset > 0)
                        min_len = offset;
        }
        if (skb->ip_summed == CHECKSUM_PARTIAL) {
                offset = skb_checksum_start_offset(skb) +
                         skb->csum_offset + sizeof(__sum16);
                if (offset > 0)
                        min_len = offset;
        }
        return min_len;
}

static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len)
{
        unsigned int old_len = skb->len;
        int ret;

        ret = __skb_grow_rcsum(skb, new_len);
        if (!ret)
                memset(skb->data + old_len, 0, new_len - old_len);
        return ret;
}

static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len)
{
        return __skb_trim_rcsum(skb, new_len);
}

static inline int __bpf_skb_change_tail(struct sk_buff *skb, u32 new_len,
                                        u64 flags)
{
        u32 max_len = BPF_SKB_MAX_LEN;
        u32 min_len = __bpf_skb_min_len(skb);
        int ret;

        if (unlikely(flags || new_len > max_len || new_len < min_len))
                return -EINVAL;
        if (skb->encapsulation)
                return -ENOTSUPP;

        /* The basic idea of this helper is that it's performing the
         * needed work to either grow or trim an skb, and eBPF program
         * rewrites the rest via helpers like bpf_skb_store_bytes(),
         * bpf_lX_csum_replace() and others rather than passing a raw
         * buffer here. This one is a slow path helper and intended
         * for replies with control messages.
         *
         * Like in bpf_skb_change_proto(), we want to keep this rather
         * minimal and without protocol specifics so that we are able
         * to separate concerns as in bpf_skb_store_bytes() should only
         * be the one responsible for writing buffers.
         *
         * It's really expected to be a slow path operation here for
         * control message replies, so we're implicitly linearizing,
         * uncloning and drop offloads from the skb by this.
         */
        ret = __bpf_try_make_writable(skb, skb->len);
        if (!ret) {
                if (new_len > skb->len)
                        ret = bpf_skb_grow_rcsum(skb, new_len);
                else if (new_len < skb->len)
                        ret = bpf_skb_trim_rcsum(skb, new_len);
                if (!ret && skb_is_gso(skb))
                        skb_gso_reset(skb);
        }
        return ret;
}

BPF_CALL_3(bpf_skb_change_tail, struct sk_buff *, skb, u32, new_len,
           u64, flags)
{
        int ret = __bpf_skb_change_tail(skb, new_len, flags);

        bpf_compute_data_pointers(skb);
        return ret;
}

static const struct bpf_func_proto bpf_skb_change_tail_proto = {
        .func           = bpf_skb_change_tail,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
};

BPF_CALL_3(sk_skb_change_tail, struct sk_buff *, skb, u32, new_len,
           u64, flags)
{
        return __bpf_skb_change_tail(skb, new_len, flags);
}

static const struct bpf_func_proto sk_skb_change_tail_proto = {
        .func           = sk_skb_change_tail,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
};

static inline int __bpf_skb_change_head(struct sk_buff *skb, u32 head_room,
                                        u64 flags)
{
        const u8 meta_len = skb_metadata_len(skb);
        u32 max_len = BPF_SKB_MAX_LEN;
        u32 new_len = skb->len + head_room;
        int ret;

        if (unlikely(flags || (int)head_room < 0 ||
                     (!skb_is_gso(skb) && new_len > max_len) ||
                     new_len < skb->len))
                return -EINVAL;

        ret = skb_cow(skb, meta_len + head_room);
        if (likely(!ret)) {
                /* Idea for this helper is that we currently only
                 * allow to expand on mac header. This means that
                 * skb->protocol network header, etc, stay as is.
                 * Compared to bpf_skb_change_tail(), we're more
                 * flexible due to not needing to linearize or
                 * reset GSO. Intention for this helper is to be
                 * used by an L3 skb that needs to push mac header
                 * for redirection into L2 device.
                 */
                __skb_push(skb, head_room);
                skb_postpush_data_move(skb, head_room, 0);
                memset(skb->data, 0, head_room);
                skb_reset_mac_header(skb);
                skb_reset_mac_len(skb);
        }

        return ret;
}

BPF_CALL_3(bpf_skb_change_head, struct sk_buff *, skb, u32, head_room,
           u64, flags)
{
        int ret = __bpf_skb_change_head(skb, head_room, flags);

        bpf_compute_data_pointers(skb);
        return ret;
}

static const struct bpf_func_proto bpf_skb_change_head_proto = {
        .func           = bpf_skb_change_head,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
};

BPF_CALL_3(sk_skb_change_head, struct sk_buff *, skb, u32, head_room,
           u64, flags)
{
        return __bpf_skb_change_head(skb, head_room, flags);
}

static const struct bpf_func_proto sk_skb_change_head_proto = {
        .func           = sk_skb_change_head,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
};

BPF_CALL_1(bpf_xdp_get_buff_len, struct xdp_buff*, xdp)
{
        return xdp_get_buff_len(xdp);
}

static const struct bpf_func_proto bpf_xdp_get_buff_len_proto = {
        .func           = bpf_xdp_get_buff_len,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
};

BTF_ID_LIST_SINGLE(bpf_xdp_get_buff_len_bpf_ids, struct, xdp_buff)

const struct bpf_func_proto bpf_xdp_get_buff_len_trace_proto = {
        .func           = bpf_xdp_get_buff_len,
        .gpl_only       = false,
        .arg1_type      = ARG_PTR_TO_BTF_ID,
        .arg1_btf_id    = &bpf_xdp_get_buff_len_bpf_ids[0],
};

static unsigned long xdp_get_metalen(const struct xdp_buff *xdp)
{
        return xdp_data_meta_unsupported(xdp) ? 0 :
               xdp->data - xdp->data_meta;
}

BPF_CALL_2(bpf_xdp_adjust_head, struct xdp_buff *, xdp, int, offset)
{
        void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame);
        unsigned long metalen = xdp_get_metalen(xdp);
        void *data_start = xdp_frame_end + metalen;
        void *data = xdp->data + offset;

        if (unlikely(data < data_start ||
                     data > xdp->data_end - ETH_HLEN))
                return -EINVAL;

        if (metalen)
                memmove(xdp->data_meta + offset,
                        xdp->data_meta, metalen);
        xdp->data_meta += offset;
        xdp->data = data;

        return 0;
}

static const struct bpf_func_proto bpf_xdp_adjust_head_proto = {
        .func           = bpf_xdp_adjust_head,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
};

void bpf_xdp_copy_buf(struct xdp_buff *xdp, unsigned long off,
                      void *buf, unsigned long len, bool flush)
{
        unsigned long ptr_len, ptr_off = 0;
        skb_frag_t *next_frag, *end_frag;
        struct skb_shared_info *sinfo;
        void *src, *dst;
        u8 *ptr_buf;

        if (likely(xdp->data_end - xdp->data >= off + len)) {
                src = flush ? buf : xdp->data + off;
                dst = flush ? xdp->data + off : buf;
                memcpy(dst, src, len);
                return;
        }

        sinfo = xdp_get_shared_info_from_buff(xdp);
        end_frag = &sinfo->frags[sinfo->nr_frags];
        next_frag = &sinfo->frags[0];

        ptr_len = xdp->data_end - xdp->data;
        ptr_buf = xdp->data;

        while (true) {
                if (off < ptr_off + ptr_len) {
                        unsigned long copy_off = off - ptr_off;
                        unsigned long copy_len = min(len, ptr_len - copy_off);

                        src = flush ? buf : ptr_buf + copy_off;
                        dst = flush ? ptr_buf + copy_off : buf;
                        memcpy(dst, src, copy_len);

                        off += copy_len;
                        len -= copy_len;
                        buf += copy_len;
                }

                if (!len || next_frag == end_frag)
                        break;

                ptr_off += ptr_len;
                ptr_buf = skb_frag_address(next_frag);
                ptr_len = skb_frag_size(next_frag);
                next_frag++;
        }
}

void *bpf_xdp_pointer(struct xdp_buff *xdp, u32 offset, u32 len)
{
        u32 size = xdp->data_end - xdp->data;
        struct skb_shared_info *sinfo;
        void *addr = xdp->data;
        int i;

        if (unlikely(offset > 0xffff || len > 0xffff))
                return ERR_PTR(-EFAULT);

        if (unlikely(offset + len > xdp_get_buff_len(xdp)))
                return ERR_PTR(-EINVAL);

        if (likely(offset < size)) /* linear area */
                goto out;

        sinfo = xdp_get_shared_info_from_buff(xdp);
        offset -= size;
        for (i = 0; i < sinfo->nr_frags; i++) { /* paged area */
                u32 frag_size = skb_frag_size(&sinfo->frags[i]);

                if  (offset < frag_size) {
                        addr = skb_frag_address(&sinfo->frags[i]);
                        size = frag_size;
                        break;
                }
                offset -= frag_size;
        }
out:
        return offset + len <= size ? addr + offset : NULL;
}

BPF_CALL_4(bpf_xdp_load_bytes, struct xdp_buff *, xdp, u32, offset,
           void *, buf, u32, len)
{
        void *ptr;

        ptr = bpf_xdp_pointer(xdp, offset, len);
        if (IS_ERR(ptr))
                return PTR_ERR(ptr);

        if (!ptr)
                bpf_xdp_copy_buf(xdp, offset, buf, len, false);
        else
                memcpy(buf, ptr, len);

        return 0;
}

static const struct bpf_func_proto bpf_xdp_load_bytes_proto = {
        .func           = bpf_xdp_load_bytes,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_PTR_TO_UNINIT_MEM,
        .arg4_type      = ARG_CONST_SIZE,
};

int __bpf_xdp_load_bytes(struct xdp_buff *xdp, u32 offset, void *buf, u32 len)
{
        return ____bpf_xdp_load_bytes(xdp, offset, buf, len);
}

BPF_CALL_4(bpf_xdp_store_bytes, struct xdp_buff *, xdp, u32, offset,
           void *, buf, u32, len)
{
        void *ptr;

        ptr = bpf_xdp_pointer(xdp, offset, len);
        if (IS_ERR(ptr))
                return PTR_ERR(ptr);

        if (!ptr)
                bpf_xdp_copy_buf(xdp, offset, buf, len, true);
        else
                memcpy(ptr, buf, len);

        return 0;
}

static const struct bpf_func_proto bpf_xdp_store_bytes_proto = {
        .func           = bpf_xdp_store_bytes,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg4_type      = ARG_CONST_SIZE,
};

int __bpf_xdp_store_bytes(struct xdp_buff *xdp, u32 offset, void *buf, u32 len)
{
        return ____bpf_xdp_store_bytes(xdp, offset, buf, len);
}

static int bpf_xdp_frags_increase_tail(struct xdp_buff *xdp, int offset)
{
        struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
        skb_frag_t *frag = &sinfo->frags[sinfo->nr_frags - 1];
        struct xdp_rxq_info *rxq = xdp->rxq;
        int tailroom;

        if (!rxq->frag_size || rxq->frag_size > xdp->frame_sz)
                return -EOPNOTSUPP;

        tailroom = rxq->frag_size - skb_frag_size(frag) -
                   skb_frag_off(frag) % rxq->frag_size;
        WARN_ON_ONCE(tailroom < 0);
        if (unlikely(offset > tailroom))
                return -EINVAL;

        memset(skb_frag_address(frag) + skb_frag_size(frag), 0, offset);
        skb_frag_size_add(frag, offset);
        sinfo->xdp_frags_size += offset;
        if (rxq->mem.type == MEM_TYPE_XSK_BUFF_POOL)
                xsk_buff_get_tail(xdp)->data_end += offset;

        return 0;
}

static struct xdp_buff *bpf_xdp_shrink_data_zc(struct xdp_buff *xdp, int shrink,
                                               bool tail, bool release)
{
        struct xdp_buff *zc_frag = tail ? xsk_buff_get_tail(xdp) :
                                          xsk_buff_get_head(xdp);

        if (release) {
                xsk_buff_del_frag(zc_frag);
        } else {
                if (tail)
                        zc_frag->data_end -= shrink;
                else
                        zc_frag->data += shrink;
        }

        return zc_frag;
}

static bool bpf_xdp_shrink_data(struct xdp_buff *xdp, skb_frag_t *frag,
                                int shrink, bool tail)
{
        enum xdp_mem_type mem_type = xdp->rxq->mem.type;
        bool release = skb_frag_size(frag) == shrink;
        netmem_ref netmem = skb_frag_netmem(frag);
        struct xdp_buff *zc_frag = NULL;

        if (mem_type == MEM_TYPE_XSK_BUFF_POOL) {
                netmem = 0;
                zc_frag = bpf_xdp_shrink_data_zc(xdp, shrink, tail, release);
        }

        if (release) {
                __xdp_return(netmem, mem_type, false, zc_frag);
        } else {
                if (!tail)
                        skb_frag_off_add(frag, shrink);
                skb_frag_size_sub(frag, shrink);
        }

        return release;
}

static int bpf_xdp_frags_shrink_tail(struct xdp_buff *xdp, int offset)
{
        struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
        int i, n_frags_free = 0, len_free = 0;

        if (unlikely(offset > (int)xdp_get_buff_len(xdp) - ETH_HLEN))
                return -EINVAL;

        for (i = sinfo->nr_frags - 1; i >= 0 && offset > 0; i--) {
                skb_frag_t *frag = &sinfo->frags[i];
                int shrink = min_t(int, offset, skb_frag_size(frag));

                len_free += shrink;
                offset -= shrink;
                if (bpf_xdp_shrink_data(xdp, frag, shrink, true))
                        n_frags_free++;
        }
        sinfo->nr_frags -= n_frags_free;
        sinfo->xdp_frags_size -= len_free;

        if (unlikely(!sinfo->nr_frags)) {
                xdp_buff_clear_frags_flag(xdp);
                xdp_buff_clear_frag_pfmemalloc(xdp);
                xdp->data_end -= offset;
        }

        return 0;
}

BPF_CALL_2(bpf_xdp_adjust_tail, struct xdp_buff *, xdp, int, offset)
{
        void *data_hard_end = xdp_data_hard_end(xdp); /* use xdp->frame_sz */
        void *data_end = xdp->data_end + offset;

        if (unlikely(xdp_buff_has_frags(xdp))) { /* non-linear xdp buff */
                if (offset < 0)
                        return bpf_xdp_frags_shrink_tail(xdp, -offset);

                return bpf_xdp_frags_increase_tail(xdp, offset);
        }

        /* Notice that xdp_data_hard_end have reserved some tailroom */
        if (unlikely(data_end > data_hard_end))
                return -EINVAL;

        if (unlikely(data_end < xdp->data + ETH_HLEN))
                return -EINVAL;

        /* Clear memory area on grow, can contain uninit kernel memory */
        if (offset > 0)
                memset(xdp->data_end, 0, offset);

        xdp->data_end = data_end;

        return 0;
}

static const struct bpf_func_proto bpf_xdp_adjust_tail_proto = {
        .func           = bpf_xdp_adjust_tail,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
};

BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset)
{
        void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame);
        void *meta = xdp->data_meta + offset;
        unsigned long metalen = xdp->data - meta;

        if (xdp_data_meta_unsupported(xdp))
                return -ENOTSUPP;
        if (unlikely(meta < xdp_frame_end ||
                     meta > xdp->data))
                return -EINVAL;
        if (unlikely(xdp_metalen_invalid(metalen)))
                return -EACCES;

        xdp->data_meta = meta;

        return 0;
}

static const struct bpf_func_proto bpf_xdp_adjust_meta_proto = {
        .func           = bpf_xdp_adjust_meta,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
};

/**
 * DOC: xdp redirect
 *
 * XDP_REDIRECT works by a three-step process, implemented in the functions
 * below:
 *
 * 1. The bpf_redirect() and bpf_redirect_map() helpers will lookup the target
 *    of the redirect and store it (along with some other metadata) in a per-CPU
 *    struct bpf_redirect_info.
 *
 * 2. When the program returns the XDP_REDIRECT return code, the driver will
 *    call xdp_do_redirect() which will use the information in struct
 *    bpf_redirect_info to actually enqueue the frame into a map type-specific
 *    bulk queue structure.
 *
 * 3. Before exiting its NAPI poll loop, the driver will call
 *    xdp_do_flush(), which will flush all the different bulk queues,
 *    thus completing the redirect. Note that xdp_do_flush() must be
 *    called before napi_complete_done() in the driver, as the
 *    XDP_REDIRECT logic relies on being inside a single NAPI instance
 *    through to the xdp_do_flush() call for RCU protection of all
 *    in-kernel data structures.
 */
/*
 * Pointers to the map entries will be kept around for this whole sequence of
 * steps, protected by RCU. However, there is no top-level rcu_read_lock() in
 * the core code; instead, the RCU protection relies on everything happening
 * inside a single NAPI poll sequence, which means it's between a pair of calls
 * to local_bh_disable()/local_bh_enable().
 *
 * The map entries are marked as __rcu and the map code makes sure to
 * dereference those pointers with rcu_dereference_check() in a way that works
 * for both sections that to hold an rcu_read_lock() and sections that are
 * called from NAPI without a separate rcu_read_lock(). The code below does not
 * use RCU annotations, but relies on those in the map code.
 */
void xdp_do_flush(void)
{
        struct list_head *lh_map, *lh_dev, *lh_xsk;

        bpf_net_ctx_get_all_used_flush_lists(&lh_map, &lh_dev, &lh_xsk);
        if (lh_dev)
                __dev_flush(lh_dev);
        if (lh_map)
                __cpu_map_flush(lh_map);
        if (lh_xsk)
                __xsk_map_flush(lh_xsk);
}
EXPORT_SYMBOL_GPL(xdp_do_flush);

#if defined(CONFIG_DEBUG_NET) && defined(CONFIG_BPF_SYSCALL)
void xdp_do_check_flushed(struct napi_struct *napi)
{
        struct list_head *lh_map, *lh_dev, *lh_xsk;
        bool missed = false;

        bpf_net_ctx_get_all_used_flush_lists(&lh_map, &lh_dev, &lh_xsk);
        if (lh_dev) {
                __dev_flush(lh_dev);
                missed = true;
        }
        if (lh_map) {
                __cpu_map_flush(lh_map);
                missed = true;
        }
        if (lh_xsk) {
                __xsk_map_flush(lh_xsk);
                missed = true;
        }

        WARN_ONCE(missed, "Missing xdp_do_flush() invocation after NAPI by %ps\n",
                  napi->poll);
}
#endif

DEFINE_STATIC_KEY_FALSE(bpf_master_redirect_enabled_key);
EXPORT_SYMBOL_GPL(bpf_master_redirect_enabled_key);

u32 xdp_master_redirect(struct xdp_buff *xdp)
{
        struct bpf_redirect_info *ri = bpf_net_ctx_get_ri();
        struct net_device *master, *slave;

        master = netdev_master_upper_dev_get_rcu(xdp->rxq->dev);
        if (unlikely(!master || !(master->flags & IFF_UP)))
                return XDP_ABORTED;
        slave = master->netdev_ops->ndo_xdp_get_xmit_slave(master, xdp);
        if (slave && slave != xdp->rxq->dev) {
                /* The target device is different from the receiving device, so
                 * redirect it to the new device.
                 * Using XDP_REDIRECT gets the correct behaviour from XDP enabled
                 * drivers to unmap the packet from their rx ring.
                 */
                ri->tgt_index = slave->ifindex;
                ri->map_id = INT_MAX;
                ri->map_type = BPF_MAP_TYPE_UNSPEC;
                return XDP_REDIRECT;
        }
        return XDP_TX;
}
EXPORT_SYMBOL_GPL(xdp_master_redirect);

static inline int __xdp_do_redirect_xsk(struct bpf_redirect_info *ri,
                                        const struct net_device *dev,
                                        struct xdp_buff *xdp,
                                        const struct bpf_prog *xdp_prog)
{
        enum bpf_map_type map_type = ri->map_type;
        void *fwd = ri->tgt_value;
        u32 map_id = ri->map_id;
        int err;

        ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
        ri->map_type = BPF_MAP_TYPE_UNSPEC;

        err = __xsk_map_redirect(fwd, xdp);
        if (unlikely(err))
                goto err;

        _trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
        return 0;
err:
        _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
        return err;
}

static __always_inline int
__xdp_do_redirect_frame(struct bpf_redirect_info *ri, struct net_device *dev,
                        struct xdp_frame *xdpf,
                        const struct bpf_prog *xdp_prog)
{
        enum bpf_map_type map_type = ri->map_type;
        void *fwd = ri->tgt_value;
        u32 map_id = ri->map_id;
        u32 flags = ri->flags;
        struct bpf_map *map;
        int err;

        ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
        ri->flags = 0;
        ri->map_type = BPF_MAP_TYPE_UNSPEC;

        if (unlikely(!xdpf)) {
                err = -EOVERFLOW;
                goto err;
        }

        switch (map_type) {
        case BPF_MAP_TYPE_DEVMAP:
                fallthrough;
        case BPF_MAP_TYPE_DEVMAP_HASH:
                if (unlikely(flags & BPF_F_BROADCAST)) {
                        map = READ_ONCE(ri->map);

                        /* The map pointer is cleared when the map is being torn
                         * down by dev_map_free()
                         */
                        if (unlikely(!map)) {
                                err = -ENOENT;
                                break;
                        }

                        WRITE_ONCE(ri->map, NULL);
                        err = dev_map_enqueue_multi(xdpf, dev, map,
                                                    flags & BPF_F_EXCLUDE_INGRESS);
                } else {
                        err = dev_map_enqueue(fwd, xdpf, dev);
                }
                break;
        case BPF_MAP_TYPE_CPUMAP:
                err = cpu_map_enqueue(fwd, xdpf, dev);
                break;
        case BPF_MAP_TYPE_UNSPEC:
                if (map_id == INT_MAX) {
                        fwd = dev_get_by_index_rcu(dev_net(dev), ri->tgt_index);
                        if (unlikely(!fwd)) {
                                err = -EINVAL;
                                break;
                        }
                        err = dev_xdp_enqueue(fwd, xdpf, dev);
                        break;
                }
                fallthrough;
        default:
                err = -EBADRQC;
        }

        if (unlikely(err))
                goto err;

        _trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
        return 0;
err:
        _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
        return err;
}

int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp,
                    const struct bpf_prog *xdp_prog)
{
        struct bpf_redirect_info *ri = bpf_net_ctx_get_ri();
        enum bpf_map_type map_type = ri->map_type;

        if (map_type == BPF_MAP_TYPE_XSKMAP)
                return __xdp_do_redirect_xsk(ri, dev, xdp, xdp_prog);

        return __xdp_do_redirect_frame(ri, dev, xdp_convert_buff_to_frame(xdp),
                                       xdp_prog);
}
EXPORT_SYMBOL_GPL(xdp_do_redirect);

int xdp_do_redirect_frame(struct net_device *dev, struct xdp_buff *xdp,
                          struct xdp_frame *xdpf,
                          const struct bpf_prog *xdp_prog)
{
        struct bpf_redirect_info *ri = bpf_net_ctx_get_ri();
        enum bpf_map_type map_type = ri->map_type;

        if (map_type == BPF_MAP_TYPE_XSKMAP)
                return __xdp_do_redirect_xsk(ri, dev, xdp, xdp_prog);

        return __xdp_do_redirect_frame(ri, dev, xdpf, xdp_prog);
}
EXPORT_SYMBOL_GPL(xdp_do_redirect_frame);

static int xdp_do_generic_redirect_map(struct net_device *dev,
                                       struct sk_buff *skb,
                                       struct xdp_buff *xdp,
                                       const struct bpf_prog *xdp_prog,
                                       void *fwd, enum bpf_map_type map_type,
                                       u32 map_id, u32 flags)
{
        struct bpf_redirect_info *ri = bpf_net_ctx_get_ri();
        struct bpf_map *map;
        int err;

        switch (map_type) {
        case BPF_MAP_TYPE_DEVMAP:
                fallthrough;
        case BPF_MAP_TYPE_DEVMAP_HASH:
                if (unlikely(flags & BPF_F_BROADCAST)) {
                        map = READ_ONCE(ri->map);

                        /* The map pointer is cleared when the map is being torn
                         * down by dev_map_free()
                         */
                        if (unlikely(!map)) {
                                err = -ENOENT;
                                break;
                        }

                        WRITE_ONCE(ri->map, NULL);
                        err = dev_map_redirect_multi(dev, skb, xdp_prog, map,
                                                     flags & BPF_F_EXCLUDE_INGRESS);
                } else {
                        err = dev_map_generic_redirect(fwd, skb, xdp_prog);
                }
                if (unlikely(err))
                        goto err;
                break;
        case BPF_MAP_TYPE_XSKMAP:
                err = xsk_generic_rcv(fwd, xdp);
                if (err)
                        goto err;
                consume_skb(skb);
                break;
        case BPF_MAP_TYPE_CPUMAP:
                err = cpu_map_generic_redirect(fwd, skb);
                if (unlikely(err))
                        goto err;
                break;
        default:
                err = -EBADRQC;
                goto err;
        }

        _trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
        return 0;
err:
        _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
        return err;
}

int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
                            struct xdp_buff *xdp,
                            const struct bpf_prog *xdp_prog)
{
        struct bpf_redirect_info *ri = bpf_net_ctx_get_ri();
        enum bpf_map_type map_type = ri->map_type;
        void *fwd = ri->tgt_value;
        u32 map_id = ri->map_id;
        u32 flags = ri->flags;
        int err;

        ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
        ri->flags = 0;
        ri->map_type = BPF_MAP_TYPE_UNSPEC;

        if (map_type == BPF_MAP_TYPE_UNSPEC && map_id == INT_MAX) {
                fwd = dev_get_by_index_rcu(dev_net(dev), ri->tgt_index);
                if (unlikely(!fwd)) {
                        err = -EINVAL;
                        goto err;
                }

                err = xdp_ok_fwd_dev(fwd, skb->len);
                if (unlikely(err))
                        goto err;

                skb->dev = fwd;
                _trace_xdp_redirect(dev, xdp_prog, ri->tgt_index);
                generic_xdp_tx(skb, xdp_prog);
                return 0;
        }

        return xdp_do_generic_redirect_map(dev, skb, xdp, xdp_prog, fwd, map_type, map_id, flags);
err:
        _trace_xdp_redirect_err(dev, xdp_prog, ri->tgt_index, err);
        return err;
}

BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags)
{
        struct bpf_redirect_info *ri = bpf_net_ctx_get_ri();

        if (unlikely(flags))
                return XDP_ABORTED;

        /* NB! Map type UNSPEC and map_id == INT_MAX (never generated
         * by map_idr) is used for ifindex based XDP redirect.
         */
        ri->tgt_index = ifindex;
        ri->map_id = INT_MAX;
        ri->map_type = BPF_MAP_TYPE_UNSPEC;

        return XDP_REDIRECT;
}

static const struct bpf_func_proto bpf_xdp_redirect_proto = {
        .func           = bpf_xdp_redirect,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_ANYTHING,
        .arg2_type      = ARG_ANYTHING,
};

BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u64, key,
           u64, flags)
{
        return map->ops->map_redirect(map, key, flags);
}

static const struct bpf_func_proto bpf_xdp_redirect_map_proto = {
        .func           = bpf_xdp_redirect_map,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_CONST_MAP_PTR,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
};

static unsigned long bpf_skb_copy(void *dst_buff, const void *skb,
                                  unsigned long off, unsigned long len)
{
        void *ptr = skb_header_pointer(skb, off, len, dst_buff);

        if (unlikely(!ptr))
                return len;
        if (ptr != dst_buff)
                memcpy(dst_buff, ptr, len);

        return 0;
}

BPF_CALL_5(bpf_skb_event_output, struct sk_buff *, skb, struct bpf_map *, map,
           u64, flags, void *, meta, u64, meta_size)
{
        u64 skb_size = (flags & BPF_F_CTXLEN_MASK) >> 32;

        if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
                return -EINVAL;
        if (unlikely(!skb || skb_size > skb->len))
                return -EFAULT;

        return bpf_event_output(map, flags, meta, meta_size, skb, skb_size,
                                bpf_skb_copy);
}

static const struct bpf_func_proto bpf_skb_event_output_proto = {
        .func           = bpf_skb_event_output,
        .gpl_only       = true,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_CONST_MAP_PTR,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg5_type      = ARG_CONST_SIZE_OR_ZERO,
};

BTF_ID_LIST_SINGLE(bpf_skb_output_btf_ids, struct, sk_buff)

const struct bpf_func_proto bpf_skb_output_proto = {
        .func           = bpf_skb_event_output,
        .gpl_only       = true,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_BTF_ID,
        .arg1_btf_id    = &bpf_skb_output_btf_ids[0],
        .arg2_type      = ARG_CONST_MAP_PTR,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg5_type      = ARG_CONST_SIZE_OR_ZERO,
};

static unsigned short bpf_tunnel_key_af(u64 flags)
{
        return flags & BPF_F_TUNINFO_IPV6 ? AF_INET6 : AF_INET;
}

BPF_CALL_4(bpf_skb_get_tunnel_key, struct sk_buff *, skb, struct bpf_tunnel_key *, to,
           u32, size, u64, flags)
{
        const struct ip_tunnel_info *info = skb_tunnel_info(skb);
        u8 compat[sizeof(struct bpf_tunnel_key)];
        void *to_orig = to;
        int err;

        if (unlikely(!info || (flags & ~(BPF_F_TUNINFO_IPV6 |
                                         BPF_F_TUNINFO_FLAGS)))) {
                err = -EINVAL;
                goto err_clear;
        }
        if (ip_tunnel_info_af(info) != bpf_tunnel_key_af(flags)) {
                err = -EPROTO;
                goto err_clear;
        }
        if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
                err = -EINVAL;
                switch (size) {
                case offsetof(struct bpf_tunnel_key, local_ipv6[0]):
                case offsetof(struct bpf_tunnel_key, tunnel_label):
                case offsetof(struct bpf_tunnel_key, tunnel_ext):
                        goto set_compat;
                case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
                        /* Fixup deprecated structure layouts here, so we have
                         * a common path later on.
                         */
                        if (ip_tunnel_info_af(info) != AF_INET)
                                goto err_clear;
set_compat:
                        to = (struct bpf_tunnel_key *)compat;
                        break;
                default:
                        goto err_clear;
                }
        }

        to->tunnel_id = be64_to_cpu(info->key.tun_id);
        to->tunnel_tos = info->key.tos;
        to->tunnel_ttl = info->key.ttl;
        if (flags & BPF_F_TUNINFO_FLAGS)
                to->tunnel_flags = ip_tunnel_flags_to_be16(info->key.tun_flags);
        else
                to->tunnel_ext = 0;

        if (flags & BPF_F_TUNINFO_IPV6) {
                memcpy(to->remote_ipv6, &info->key.u.ipv6.src,
                       sizeof(to->remote_ipv6));
                memcpy(to->local_ipv6, &info->key.u.ipv6.dst,
                       sizeof(to->local_ipv6));
                to->tunnel_label = be32_to_cpu(info->key.label);
        } else {
                to->remote_ipv4 = be32_to_cpu(info->key.u.ipv4.src);
                memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3);
                to->local_ipv4 = be32_to_cpu(info->key.u.ipv4.dst);
                memset(&to->local_ipv6[1], 0, sizeof(__u32) * 3);
                to->tunnel_label = 0;
        }

        if (unlikely(size != sizeof(struct bpf_tunnel_key)))
                memcpy(to_orig, to, size);

        return 0;
err_clear:
        memset(to_orig, 0, size);
        return err;
}

static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto = {
        .func           = bpf_skb_get_tunnel_key,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_UNINIT_MEM,
        .arg3_type      = ARG_CONST_SIZE,
        .arg4_type      = ARG_ANYTHING,
};

BPF_CALL_3(bpf_skb_get_tunnel_opt, struct sk_buff *, skb, u8 *, to, u32, size)
{
        const struct ip_tunnel_info *info = skb_tunnel_info(skb);
        int err;

        if (unlikely(!info ||
                     !ip_tunnel_is_options_present(info->key.tun_flags))) {
                err = -ENOENT;
                goto err_clear;
        }
        if (unlikely(size < info->options_len)) {
                err = -ENOMEM;
                goto err_clear;
        }

        ip_tunnel_info_opts_get(to, info);
        if (size > info->options_len)
                memset(to + info->options_len, 0, size - info->options_len);

        return info->options_len;
err_clear:
        memset(to, 0, size);
        return err;
}

static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto = {
        .func           = bpf_skb_get_tunnel_opt,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_UNINIT_MEM,
        .arg3_type      = ARG_CONST_SIZE,
};

static struct metadata_dst __percpu *md_dst;

BPF_CALL_4(bpf_skb_set_tunnel_key, struct sk_buff *, skb,
           const struct bpf_tunnel_key *, from, u32, size, u64, flags)
{
        struct metadata_dst *md = this_cpu_ptr(md_dst);
        u8 compat[sizeof(struct bpf_tunnel_key)];
        struct ip_tunnel_info *info;

        if (unlikely(flags & ~(BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX |
                               BPF_F_DONT_FRAGMENT | BPF_F_SEQ_NUMBER |
                               BPF_F_NO_TUNNEL_KEY)))
                return -EINVAL;
        if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
                switch (size) {
                case offsetof(struct bpf_tunnel_key, local_ipv6[0]):
                case offsetof(struct bpf_tunnel_key, tunnel_label):
                case offsetof(struct bpf_tunnel_key, tunnel_ext):
                case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
                        /* Fixup deprecated structure layouts here, so we have
                         * a common path later on.
                         */
                        memcpy(compat, from, size);
                        memset(compat + size, 0, sizeof(compat) - size);
                        from = (const struct bpf_tunnel_key *) compat;
                        break;
                default:
                        return -EINVAL;
                }
        }
        if (unlikely((!(flags & BPF_F_TUNINFO_IPV6) && from->tunnel_label) ||
                     from->tunnel_ext))
                return -EINVAL;

        skb_dst_drop(skb);
        dst_hold((struct dst_entry *) md);
        skb_dst_set(skb, (struct dst_entry *) md);

        info = &md->u.tun_info;
        memset(info, 0, sizeof(*info));
        info->mode = IP_TUNNEL_INFO_TX;

        __set_bit(IP_TUNNEL_NOCACHE_BIT, info->key.tun_flags);
        __assign_bit(IP_TUNNEL_DONT_FRAGMENT_BIT, info->key.tun_flags,
                     flags & BPF_F_DONT_FRAGMENT);
        __assign_bit(IP_TUNNEL_CSUM_BIT, info->key.tun_flags,
                     !(flags & BPF_F_ZERO_CSUM_TX));
        __assign_bit(IP_TUNNEL_SEQ_BIT, info->key.tun_flags,
                     flags & BPF_F_SEQ_NUMBER);
        __assign_bit(IP_TUNNEL_KEY_BIT, info->key.tun_flags,
                     !(flags & BPF_F_NO_TUNNEL_KEY));

        info->key.tun_id = cpu_to_be64(from->tunnel_id);
        info->key.tos = from->tunnel_tos;
        info->key.ttl = from->tunnel_ttl;

        if (flags & BPF_F_TUNINFO_IPV6) {
                info->mode |= IP_TUNNEL_INFO_IPV6;
                memcpy(&info->key.u.ipv6.dst, from->remote_ipv6,
                       sizeof(from->remote_ipv6));
                memcpy(&info->key.u.ipv6.src, from->local_ipv6,
                       sizeof(from->local_ipv6));
                info->key.label = cpu_to_be32(from->tunnel_label) &
                                  IPV6_FLOWLABEL_MASK;
        } else {
                info->key.u.ipv4.dst = cpu_to_be32(from->remote_ipv4);
                info->key.u.ipv4.src = cpu_to_be32(from->local_ipv4);
                info->key.flow_flags = FLOWI_FLAG_ANYSRC;
        }

        return 0;
}

static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto = {
        .func           = bpf_skb_set_tunnel_key,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE,
        .arg4_type      = ARG_ANYTHING,
};

BPF_CALL_3(bpf_skb_set_tunnel_opt, struct sk_buff *, skb,
           const u8 *, from, u32, size)
{
        struct ip_tunnel_info *info = skb_tunnel_info(skb);
        const struct metadata_dst *md = this_cpu_ptr(md_dst);
        IP_TUNNEL_DECLARE_FLAGS(present) = { };

        if (unlikely(info != &md->u.tun_info || (size & (sizeof(u32) - 1))))
                return -EINVAL;
        if (unlikely(size > IP_TUNNEL_OPTS_MAX))
                return -ENOMEM;

        ip_tunnel_set_options_present(present);
        ip_tunnel_info_opts_set(info, from, size, present);

        return 0;
}

static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto = {
        .func           = bpf_skb_set_tunnel_opt,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE,
};

static const struct bpf_func_proto *
bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)
{
        if (!md_dst) {
                struct metadata_dst __percpu *tmp;

                tmp = metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX,
                                                METADATA_IP_TUNNEL,
                                                GFP_KERNEL);
                if (!tmp)
                        return NULL;
                if (cmpxchg(&md_dst, NULL, tmp))
                        metadata_dst_free_percpu(tmp);
        }

        switch (which) {
        case BPF_FUNC_skb_set_tunnel_key:
                return &bpf_skb_set_tunnel_key_proto;
        case BPF_FUNC_skb_set_tunnel_opt:
                return &bpf_skb_set_tunnel_opt_proto;
        default:
                return NULL;
        }
}

BPF_CALL_3(bpf_skb_under_cgroup, struct sk_buff *, skb, struct bpf_map *, map,
           u32, idx)
{
        struct bpf_array *array = container_of(map, struct bpf_array, map);
        struct cgroup *cgrp;
        struct sock *sk;

        sk = skb_to_full_sk(skb);
        if (!sk || !sk_fullsock(sk))
                return -ENOENT;
        if (unlikely(idx >= array->map.max_entries))
                return -E2BIG;

        cgrp = READ_ONCE(array->ptrs[idx]);
        if (unlikely(!cgrp))
                return -EAGAIN;

        return sk_under_cgroup_hierarchy(sk, cgrp);
}

static const struct bpf_func_proto bpf_skb_under_cgroup_proto = {
        .func           = bpf_skb_under_cgroup,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_CONST_MAP_PTR,
        .arg3_type      = ARG_ANYTHING,
};

#ifdef CONFIG_SOCK_CGROUP_DATA
static inline u64 __bpf_sk_cgroup_id(struct sock *sk)
{
        struct cgroup *cgrp;

        sk = sk_to_full_sk(sk);
        if (!sk || !sk_fullsock(sk))
                return 0;

        cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
        return cgroup_id(cgrp);
}

BPF_CALL_1(bpf_skb_cgroup_id, const struct sk_buff *, skb)
{
        return __bpf_sk_cgroup_id(skb->sk);
}

static const struct bpf_func_proto bpf_skb_cgroup_id_proto = {
        .func           = bpf_skb_cgroup_id,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
};

static inline u64 __bpf_sk_ancestor_cgroup_id(struct sock *sk,
                                              int ancestor_level)
{
        struct cgroup *ancestor;
        struct cgroup *cgrp;

        sk = sk_to_full_sk(sk);
        if (!sk || !sk_fullsock(sk))
                return 0;

        cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
        ancestor = cgroup_ancestor(cgrp, ancestor_level);
        if (!ancestor)
                return 0;

        return cgroup_id(ancestor);
}

BPF_CALL_2(bpf_skb_ancestor_cgroup_id, const struct sk_buff *, skb, int,
           ancestor_level)
{
        return __bpf_sk_ancestor_cgroup_id(skb->sk, ancestor_level);
}

static const struct bpf_func_proto bpf_skb_ancestor_cgroup_id_proto = {
        .func           = bpf_skb_ancestor_cgroup_id,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
};

BPF_CALL_1(bpf_sk_cgroup_id, struct sock *, sk)
{
        return __bpf_sk_cgroup_id(sk);
}

static const struct bpf_func_proto bpf_sk_cgroup_id_proto = {
        .func           = bpf_sk_cgroup_id,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
};

BPF_CALL_2(bpf_sk_ancestor_cgroup_id, struct sock *, sk, int, ancestor_level)
{
        return __bpf_sk_ancestor_cgroup_id(sk, ancestor_level);
}

static const struct bpf_func_proto bpf_sk_ancestor_cgroup_id_proto = {
        .func           = bpf_sk_ancestor_cgroup_id,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
        .arg2_type      = ARG_ANYTHING,
};
#endif

static unsigned long bpf_xdp_copy(void *dst, const void *ctx,
                                  unsigned long off, unsigned long len)
{
        struct xdp_buff *xdp = (struct xdp_buff *)ctx;

        bpf_xdp_copy_buf(xdp, off, dst, len, false);
        return 0;
}

BPF_CALL_5(bpf_xdp_event_output, struct xdp_buff *, xdp, struct bpf_map *, map,
           u64, flags, void *, meta, u64, meta_size)
{
        u64 xdp_size = (flags & BPF_F_CTXLEN_MASK) >> 32;

        if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
                return -EINVAL;

        if (unlikely(!xdp || xdp_size > xdp_get_buff_len(xdp)))
                return -EFAULT;

        return bpf_event_output(map, flags, meta, meta_size, xdp,
                                xdp_size, bpf_xdp_copy);
}

static const struct bpf_func_proto bpf_xdp_event_output_proto = {
        .func           = bpf_xdp_event_output,
        .gpl_only       = true,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_CONST_MAP_PTR,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg5_type      = ARG_CONST_SIZE_OR_ZERO,
};

BTF_ID_LIST_SINGLE(bpf_xdp_output_btf_ids, struct, xdp_buff)

const struct bpf_func_proto bpf_xdp_output_proto = {
        .func           = bpf_xdp_event_output,
        .gpl_only       = true,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_BTF_ID,
        .arg1_btf_id    = &bpf_xdp_output_btf_ids[0],
        .arg2_type      = ARG_CONST_MAP_PTR,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg5_type      = ARG_CONST_SIZE_OR_ZERO,
};

BPF_CALL_1(bpf_get_socket_cookie, struct sk_buff *, skb)
{
        return skb->sk ? __sock_gen_cookie(skb->sk) : 0;
}

static const struct bpf_func_proto bpf_get_socket_cookie_proto = {
        .func           = bpf_get_socket_cookie,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
};

BPF_CALL_1(bpf_get_socket_cookie_sock_addr, struct bpf_sock_addr_kern *, ctx)
{
        return __sock_gen_cookie(ctx->sk);
}

static const struct bpf_func_proto bpf_get_socket_cookie_sock_addr_proto = {
        .func           = bpf_get_socket_cookie_sock_addr,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
};

BPF_CALL_1(bpf_get_socket_cookie_sock, struct sock *, ctx)
{
        return __sock_gen_cookie(ctx);
}

static const struct bpf_func_proto bpf_get_socket_cookie_sock_proto = {
        .func           = bpf_get_socket_cookie_sock,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
};

BPF_CALL_1(bpf_get_socket_ptr_cookie, struct sock *, sk)
{
        return sk ? sock_gen_cookie(sk) : 0;
}

const struct bpf_func_proto bpf_get_socket_ptr_cookie_proto = {
        .func           = bpf_get_socket_ptr_cookie,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON | PTR_MAYBE_NULL,
};

BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
{
        return __sock_gen_cookie(ctx->sk);
}

static const struct bpf_func_proto bpf_get_socket_cookie_sock_ops_proto = {
        .func           = bpf_get_socket_cookie_sock_ops,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
};

static u64 __bpf_get_netns_cookie(struct sock *sk)
{
        const struct net *net = sk ? sock_net(sk) : &init_net;

        return net->net_cookie;
}

BPF_CALL_1(bpf_get_netns_cookie, struct sk_buff *, skb)
{
        return __bpf_get_netns_cookie(skb && skb->sk ? skb->sk : NULL);
}

static const struct bpf_func_proto bpf_get_netns_cookie_proto = {
        .func           = bpf_get_netns_cookie,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX_OR_NULL,
};

BPF_CALL_1(bpf_get_netns_cookie_sock, struct sock *, ctx)
{
        return __bpf_get_netns_cookie(ctx);
}

static const struct bpf_func_proto bpf_get_netns_cookie_sock_proto = {
        .func           = bpf_get_netns_cookie_sock,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX_OR_NULL,
};

BPF_CALL_1(bpf_get_netns_cookie_sock_addr, struct bpf_sock_addr_kern *, ctx)
{
        return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
}

static const struct bpf_func_proto bpf_get_netns_cookie_sock_addr_proto = {
        .func           = bpf_get_netns_cookie_sock_addr,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX_OR_NULL,
};

BPF_CALL_1(bpf_get_netns_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
{
        return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
}

static const struct bpf_func_proto bpf_get_netns_cookie_sock_ops_proto = {
        .func           = bpf_get_netns_cookie_sock_ops,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX_OR_NULL,
};

BPF_CALL_1(bpf_get_netns_cookie_sk_msg, struct sk_msg *, ctx)
{
        return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
}

static const struct bpf_func_proto bpf_get_netns_cookie_sk_msg_proto = {
        .func           = bpf_get_netns_cookie_sk_msg,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX_OR_NULL,
};

BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb)
{
        struct sock *sk = sk_to_full_sk(skb->sk);
        kuid_t kuid;

        if (!sk || !sk_fullsock(sk))
                return overflowuid;
        kuid = sock_net_uid(sock_net(sk), sk);
        return from_kuid_munged(sock_net(sk)->user_ns, kuid);
}

static const struct bpf_func_proto bpf_get_socket_uid_proto = {
        .func           = bpf_get_socket_uid,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
};

static int sk_bpf_set_get_cb_flags(struct sock *sk, char *optval, bool getopt)
{
        u32 sk_bpf_cb_flags;

        if (getopt) {
                *(u32 *)optval = sk->sk_bpf_cb_flags;
                return 0;
        }

        sk_bpf_cb_flags = *(u32 *)optval;

        if (sk_bpf_cb_flags & ~SK_BPF_CB_MASK)
                return -EINVAL;

        sk->sk_bpf_cb_flags = sk_bpf_cb_flags;

        return 0;
}

static int sol_socket_sockopt(struct sock *sk, int optname,
                              char *optval, int *optlen,
                              bool getopt)
{
        switch (optname) {
        case SO_REUSEADDR:
        case SO_SNDBUF:
        case SO_RCVBUF:
        case SO_KEEPALIVE:
        case SO_PRIORITY:
        case SO_REUSEPORT:
        case SO_RCVLOWAT:
        case SO_MARK:
        case SO_MAX_PACING_RATE:
        case SO_BINDTOIFINDEX:
        case SO_TXREHASH:
        case SK_BPF_CB_FLAGS:
                if (*optlen != sizeof(int))
                        return -EINVAL;
                break;
        case SO_BINDTODEVICE:
                break;
        default:
                return -EINVAL;
        }

        if (optname == SK_BPF_CB_FLAGS)
                return sk_bpf_set_get_cb_flags(sk, optval, getopt);

        if (getopt) {
                if (optname == SO_BINDTODEVICE)
                        return -EINVAL;
                return sk_getsockopt(sk, SOL_SOCKET, optname,
                                     KERNEL_SOCKPTR(optval),
                                     KERNEL_SOCKPTR(optlen));
        }

        return sk_setsockopt(sk, SOL_SOCKET, optname,
                             KERNEL_SOCKPTR(optval), *optlen);
}

static int bpf_sol_tcp_getsockopt(struct sock *sk, int optname,
                                  char *optval, int optlen)
{
        if (optlen != sizeof(int))
                return -EINVAL;

        switch (optname) {
        case TCP_BPF_SOCK_OPS_CB_FLAGS: {
                int cb_flags = tcp_sk(sk)->bpf_sock_ops_cb_flags;

                memcpy(optval, &cb_flags, optlen);
                break;
        }
        case TCP_BPF_RTO_MIN: {
                int rto_min_us = jiffies_to_usecs(inet_csk(sk)->icsk_rto_min);

                memcpy(optval, &rto_min_us, optlen);
                break;
        }
        case TCP_BPF_DELACK_MAX: {
                int delack_max_us = jiffies_to_usecs(inet_csk(sk)->icsk_delack_max);

                memcpy(optval, &delack_max_us, optlen);
                break;
        }
        default:
                return -EINVAL;
        }

        return 0;
}

static int bpf_sol_tcp_setsockopt(struct sock *sk, int optname,
                                  char *optval, int optlen)
{
        struct tcp_sock *tp = tcp_sk(sk);
        unsigned long timeout;
        int val;

        if (optlen != sizeof(int))
                return -EINVAL;

        val = *(int *)optval;

        /* Only some options are supported */
        switch (optname) {
        case TCP_BPF_IW:
                if (val <= 0 || tp->data_segs_out > tp->syn_data)
                        return -EINVAL;
                tcp_snd_cwnd_set(tp, val);
                break;
        case TCP_BPF_SNDCWND_CLAMP:
                if (val <= 0)
                        return -EINVAL;
                tp->snd_cwnd_clamp = val;
                WRITE_ONCE(tp->snd_ssthresh, val);
                break;
        case TCP_BPF_DELACK_MAX:
                timeout = usecs_to_jiffies(val);
                if (timeout > TCP_DELACK_MAX ||
                    timeout < TCP_TIMEOUT_MIN)
                        return -EINVAL;
                inet_csk(sk)->icsk_delack_max = timeout;
                break;
        case TCP_BPF_RTO_MIN:
                timeout = usecs_to_jiffies(val);
                if (timeout > TCP_RTO_MIN ||
                    timeout < TCP_TIMEOUT_MIN)
                        return -EINVAL;
                inet_csk(sk)->icsk_rto_min = timeout;
                break;
        case TCP_BPF_SOCK_OPS_CB_FLAGS:
                if (val & ~(BPF_SOCK_OPS_ALL_CB_FLAGS))
                        return -EINVAL;
                tp->bpf_sock_ops_cb_flags = val;
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static int sol_tcp_sockopt_congestion(struct sock *sk, char *optval,
                                      int *optlen, bool getopt)
{
        struct tcp_sock *tp;
        int ret;

        if (*optlen < 2)
                return -EINVAL;

        if (getopt) {
                if (!inet_csk(sk)->icsk_ca_ops)
                        return -EINVAL;
                /* BPF expects NULL-terminated tcp-cc string */
                optval[--(*optlen)] = '\0';
                return do_tcp_getsockopt(sk, SOL_TCP, TCP_CONGESTION,
                                         KERNEL_SOCKPTR(optval),
                                         KERNEL_SOCKPTR(optlen));
        }

        /* "cdg" is the only cc that alloc a ptr
         * in inet_csk_ca area.  The bpf-tcp-cc may
         * overwrite this ptr after switching to cdg.
         */
        if (*optlen >= sizeof("cdg") - 1 && !strncmp("cdg", optval, *optlen))
                return -ENOTSUPP;

        /* It stops this looping
         *
         * .init => bpf_setsockopt(tcp_cc) => .init =>
         * bpf_setsockopt(tcp_cc)" => .init => ....
         *
         * The second bpf_setsockopt(tcp_cc) is not allowed
         * in order to break the loop when both .init
         * are the same bpf prog.
         *
         * This applies even the second bpf_setsockopt(tcp_cc)
         * does not cause a loop.  This limits only the first
         * '.init' can call bpf_setsockopt(TCP_CONGESTION) to
         * pick a fallback cc (eg. peer does not support ECN)
         * and the second '.init' cannot fallback to
         * another.
         */
        tp = tcp_sk(sk);
        if (tp->bpf_chg_cc_inprogress)
                return -EBUSY;

        tp->bpf_chg_cc_inprogress = 1;
        ret = do_tcp_setsockopt(sk, SOL_TCP, TCP_CONGESTION,
                                KERNEL_SOCKPTR(optval), *optlen);
        tp->bpf_chg_cc_inprogress = 0;
        return ret;
}

static int sol_tcp_sockopt(struct sock *sk, int optname,
                           char *optval, int *optlen,
                           bool getopt)
{
        if (!sk_is_tcp(sk))
                return -EINVAL;

        switch (optname) {
        case TCP_NODELAY:
        case TCP_MAXSEG:
        case TCP_KEEPIDLE:
        case TCP_KEEPINTVL:
        case TCP_KEEPCNT:
        case TCP_SYNCNT:
        case TCP_WINDOW_CLAMP:
        case TCP_THIN_LINEAR_TIMEOUTS:
        case TCP_USER_TIMEOUT:
        case TCP_NOTSENT_LOWAT:
        case TCP_SAVE_SYN:
        case TCP_RTO_MAX_MS:
                if (*optlen != sizeof(int))
                        return -EINVAL;
                break;
        case TCP_CONGESTION:
                return sol_tcp_sockopt_congestion(sk, optval, optlen, getopt);
        case TCP_SAVED_SYN:
                if (*optlen < 1)
                        return -EINVAL;
                break;
        default:
                if (getopt)
                        return bpf_sol_tcp_getsockopt(sk, optname, optval, *optlen);
                return bpf_sol_tcp_setsockopt(sk, optname, optval, *optlen);
        }

        if (getopt) {
                if (optname == TCP_SAVED_SYN) {
                        struct tcp_sock *tp = tcp_sk(sk);

                        if (!tp->saved_syn ||
                            *optlen > tcp_saved_syn_len(tp->saved_syn))
                                return -EINVAL;
                        memcpy(optval, tp->saved_syn->data, *optlen);
                        /* It cannot free tp->saved_syn here because it
                         * does not know if the user space still needs it.
                         */
                        return 0;
                }

                return do_tcp_getsockopt(sk, SOL_TCP, optname,
                                         KERNEL_SOCKPTR(optval),
                                         KERNEL_SOCKPTR(optlen));
        }

        return do_tcp_setsockopt(sk, SOL_TCP, optname,
                                 KERNEL_SOCKPTR(optval), *optlen);
}

static bool sk_allows_sol_ip_sockopt(struct sock *sk)
{
        switch (sk->sk_family) {
        case AF_INET:
                return true;
        case AF_INET6:
                /* Allow getting/setting sockopt for possible ipv4-mapped ipv6 socket. */
                return sk->sk_type != SOCK_RAW && !ipv6_only_sock(sk);
        default:
                return false;
        }
}

static int sol_ip_sockopt(struct sock *sk, int optname,
                          char *optval, int *optlen,
                          bool getopt)
{
        if (!sk_allows_sol_ip_sockopt(sk))
                return -EINVAL;

        switch (optname) {
        case IP_TOS:
                if (*optlen != sizeof(int))
                        return -EINVAL;
                break;
        default:
                return -EINVAL;
        }

        if (getopt)
                return do_ip_getsockopt(sk, SOL_IP, optname,
                                        KERNEL_SOCKPTR(optval),
                                        KERNEL_SOCKPTR(optlen));

        return do_ip_setsockopt(sk, SOL_IP, optname,
                                KERNEL_SOCKPTR(optval), *optlen);
}

static int sol_ipv6_sockopt(struct sock *sk, int optname,
                            char *optval, int *optlen,
                            bool getopt)
{
        if (sk->sk_family != AF_INET6)
                return -EINVAL;

        switch (optname) {
        case IPV6_TCLASS:
        case IPV6_AUTOFLOWLABEL:
                if (*optlen != sizeof(int))
                        return -EINVAL;
                break;
        default:
                return -EINVAL;
        }

        if (getopt)
                return do_ipv6_getsockopt(sk, SOL_IPV6, optname,
                                          KERNEL_SOCKPTR(optval),
                                          KERNEL_SOCKPTR(optlen));

        return do_ipv6_setsockopt(sk, SOL_IPV6, optname,
                                  KERNEL_SOCKPTR(optval), *optlen);
}

static int __bpf_setsockopt(struct sock *sk, int level, int optname,
                            char *optval, int optlen)
{
        if (!sk_fullsock(sk))
                return -EINVAL;

        if (level == SOL_SOCKET)
                return sol_socket_sockopt(sk, optname, optval, &optlen, false);
        else if (IS_ENABLED(CONFIG_INET) && level == SOL_IP)
                return sol_ip_sockopt(sk, optname, optval, &optlen, false);
        else if (IS_ENABLED(CONFIG_IPV6) && level == SOL_IPV6)
                return sol_ipv6_sockopt(sk, optname, optval, &optlen, false);
        else if (IS_ENABLED(CONFIG_INET) && level == SOL_TCP)
                return sol_tcp_sockopt(sk, optname, optval, &optlen, false);

        return -EINVAL;
}

static bool is_locked_tcp_sock_ops(struct bpf_sock_ops_kern *bpf_sock)
{
        return bpf_sock->op <= BPF_SOCK_OPS_WRITE_HDR_OPT_CB;
}

static int _bpf_setsockopt(struct sock *sk, int level, int optname,
                           char *optval, int optlen)
{
        if (sk_fullsock(sk))
                sock_owned_by_me(sk);
        return __bpf_setsockopt(sk, level, optname, optval, optlen);
}

static int __bpf_getsockopt(struct sock *sk, int level, int optname,
                            char *optval, int optlen)
{
        int err, saved_optlen = optlen;

        if (!sk_fullsock(sk)) {
                err = -EINVAL;
                goto done;
        }

        if (level == SOL_SOCKET)
                err = sol_socket_sockopt(sk, optname, optval, &optlen, true);
        else if (IS_ENABLED(CONFIG_INET) && level == SOL_TCP)
                err = sol_tcp_sockopt(sk, optname, optval, &optlen, true);
        else if (IS_ENABLED(CONFIG_INET) && level == SOL_IP)
                err = sol_ip_sockopt(sk, optname, optval, &optlen, true);
        else if (IS_ENABLED(CONFIG_IPV6) && level == SOL_IPV6)
                err = sol_ipv6_sockopt(sk, optname, optval, &optlen, true);
        else
                err = -EINVAL;

done:
        if (err)
                optlen = 0;
        if (optlen < saved_optlen)
                memset(optval + optlen, 0, saved_optlen - optlen);
        return err;
}

static int _bpf_getsockopt(struct sock *sk, int level, int optname,
                           char *optval, int optlen)
{
        if (sk_fullsock(sk))
                sock_owned_by_me(sk);
        return __bpf_getsockopt(sk, level, optname, optval, optlen);
}

BPF_CALL_5(bpf_sk_setsockopt, struct sock *, sk, int, level,
           int, optname, char *, optval, int, optlen)
{
        return _bpf_setsockopt(sk, level, optname, optval, optlen);
}

const struct bpf_func_proto bpf_sk_setsockopt_proto = {
        .func           = bpf_sk_setsockopt,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg5_type      = ARG_CONST_SIZE,
};

BPF_CALL_5(bpf_sk_getsockopt, struct sock *, sk, int, level,
           int, optname, char *, optval, int, optlen)
{
        return _bpf_getsockopt(sk, level, optname, optval, optlen);
}

const struct bpf_func_proto bpf_sk_getsockopt_proto = {
        .func           = bpf_sk_getsockopt,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_PTR_TO_UNINIT_MEM,
        .arg5_type      = ARG_CONST_SIZE,
};

BPF_CALL_5(bpf_sk_setsockopt_nodelay, struct sock *, sk, int, level,
           int, optname, char *, optval, int, optlen)
{
        /*
         * TCP_NODELAY triggers tcp_push_pending_frames() and re-enters
         * CA_EVENT_TX_START in bpf_tcp_cc.
         */
        if (level == SOL_TCP && optname == TCP_NODELAY)
                return -EOPNOTSUPP;

        return _bpf_setsockopt(sk, level, optname, optval, optlen);
}

const struct bpf_func_proto bpf_sk_setsockopt_nodelay_proto = {
        .func           = bpf_sk_setsockopt_nodelay,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg5_type      = ARG_CONST_SIZE,
};

BPF_CALL_5(bpf_unlocked_sk_setsockopt, struct sock *, sk, int, level,
           int, optname, char *, optval, int, optlen)
{
        return __bpf_setsockopt(sk, level, optname, optval, optlen);
}

const struct bpf_func_proto bpf_unlocked_sk_setsockopt_proto = {
        .func           = bpf_unlocked_sk_setsockopt,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg5_type      = ARG_CONST_SIZE,
};

BPF_CALL_5(bpf_unlocked_sk_getsockopt, struct sock *, sk, int, level,
           int, optname, char *, optval, int, optlen)
{
        return __bpf_getsockopt(sk, level, optname, optval, optlen);
}

const struct bpf_func_proto bpf_unlocked_sk_getsockopt_proto = {
        .func           = bpf_unlocked_sk_getsockopt,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_PTR_TO_UNINIT_MEM,
        .arg5_type      = ARG_CONST_SIZE,
};

BPF_CALL_5(bpf_sock_addr_setsockopt, struct bpf_sock_addr_kern *, ctx,
           int, level, int, optname, char *, optval, int, optlen)
{
        return _bpf_setsockopt(ctx->sk, level, optname, optval, optlen);
}

static const struct bpf_func_proto bpf_sock_addr_setsockopt_proto = {
        .func           = bpf_sock_addr_setsockopt,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg5_type      = ARG_CONST_SIZE,
};

BPF_CALL_5(bpf_sock_addr_getsockopt, struct bpf_sock_addr_kern *, ctx,
           int, level, int, optname, char *, optval, int, optlen)
{
        return _bpf_getsockopt(ctx->sk, level, optname, optval, optlen);
}

static const struct bpf_func_proto bpf_sock_addr_getsockopt_proto = {
        .func           = bpf_sock_addr_getsockopt,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_PTR_TO_UNINIT_MEM,
        .arg5_type      = ARG_CONST_SIZE,
};

static int sk_bpf_set_get_bypass_prot_mem(struct sock *sk,
                                          char *optval, int optlen,
                                          bool getopt)
{
        int val;

        if (optlen != sizeof(int))
                return -EINVAL;

        if (!sk_has_account(sk))
                return -EOPNOTSUPP;

        if (getopt) {
                *(int *)optval = sk->sk_bypass_prot_mem;
                return 0;
        }

        val = *(int *)optval;
        if (val < 0 || val > 1)
                return -EINVAL;

        sk->sk_bypass_prot_mem = val;
        return 0;
}

BPF_CALL_5(bpf_sock_create_setsockopt, struct sock *, sk, int, level,
           int, optname, char *, optval, int, optlen)
{
        if (level == SOL_SOCKET && optname == SK_BPF_BYPASS_PROT_MEM)
                return sk_bpf_set_get_bypass_prot_mem(sk, optval, optlen, false);

        return __bpf_setsockopt(sk, level, optname, optval, optlen);
}

static const struct bpf_func_proto bpf_sock_create_setsockopt_proto = {
        .func           = bpf_sock_create_setsockopt,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg5_type      = ARG_CONST_SIZE,
};

BPF_CALL_5(bpf_sock_create_getsockopt, struct sock *, sk, int, level,
           int, optname, char *, optval, int, optlen)
{
        if (level == SOL_SOCKET && optname == SK_BPF_BYPASS_PROT_MEM) {
                int err = sk_bpf_set_get_bypass_prot_mem(sk, optval, optlen, true);

                if (err)
                        memset(optval, 0, optlen);

                return err;
        }

        return __bpf_getsockopt(sk, level, optname, optval, optlen);
}

static const struct bpf_func_proto bpf_sock_create_getsockopt_proto = {
        .func           = bpf_sock_create_getsockopt,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_PTR_TO_UNINIT_MEM,
        .arg5_type      = ARG_CONST_SIZE,
};

BPF_CALL_5(bpf_sock_ops_setsockopt, struct bpf_sock_ops_kern *, bpf_sock,
           int, level, int, optname, char *, optval, int, optlen)
{
        if (!is_locked_tcp_sock_ops(bpf_sock))
                return -EOPNOTSUPP;

        /* TCP_NODELAY triggers tcp_push_pending_frames() and re-enters these callbacks. */
        if ((bpf_sock->op == BPF_SOCK_OPS_HDR_OPT_LEN_CB ||
             bpf_sock->op == BPF_SOCK_OPS_WRITE_HDR_OPT_CB) &&
            level == SOL_TCP && optname == TCP_NODELAY)
                return -EOPNOTSUPP;

        return _bpf_setsockopt(bpf_sock->sk, level, optname, optval, optlen);
}

static const struct bpf_func_proto bpf_sock_ops_setsockopt_proto = {
        .func           = bpf_sock_ops_setsockopt,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg5_type      = ARG_CONST_SIZE,
};

static int bpf_sock_ops_get_syn(struct bpf_sock_ops_kern *bpf_sock,
                                int optname, const u8 **start)
{
        struct sk_buff *syn_skb = bpf_sock->syn_skb;
        const u8 *hdr_start;
        int ret;

        if (syn_skb) {
                /* sk is a request_sock here */

                if (optname == TCP_BPF_SYN) {
                        hdr_start = syn_skb->data;
                        ret = tcp_hdrlen(syn_skb);
                } else if (optname == TCP_BPF_SYN_IP) {
                        hdr_start = skb_network_header(syn_skb);
                        ret = skb_network_header_len(syn_skb) +
                                tcp_hdrlen(syn_skb);
                } else {
                        /* optname == TCP_BPF_SYN_MAC */
                        hdr_start = skb_mac_header(syn_skb);
                        ret = skb_mac_header_len(syn_skb) +
                                skb_network_header_len(syn_skb) +
                                tcp_hdrlen(syn_skb);
                }
        } else {
                struct sock *sk = bpf_sock->sk;
                struct saved_syn *saved_syn;

                if (sk->sk_state == TCP_NEW_SYN_RECV)
                        /* synack retransmit. bpf_sock->syn_skb will
                         * not be available.  It has to resort to
                         * saved_syn (if it is saved).
                         */
                        saved_syn = inet_reqsk(sk)->saved_syn;
                else
                        saved_syn = tcp_sk(sk)->saved_syn;

                if (!saved_syn)
                        return -ENOENT;

                if (optname == TCP_BPF_SYN) {
                        hdr_start = saved_syn->data +
                                saved_syn->mac_hdrlen +
                                saved_syn->network_hdrlen;
                        ret = saved_syn->tcp_hdrlen;
                } else if (optname == TCP_BPF_SYN_IP) {
                        hdr_start = saved_syn->data +
                                saved_syn->mac_hdrlen;
                        ret = saved_syn->network_hdrlen +
                                saved_syn->tcp_hdrlen;
                } else {
                        /* optname == TCP_BPF_SYN_MAC */

                        /* TCP_SAVE_SYN may not have saved the mac hdr */
                        if (!saved_syn->mac_hdrlen)
                                return -ENOENT;

                        hdr_start = saved_syn->data;
                        ret = saved_syn->mac_hdrlen +
                                saved_syn->network_hdrlen +
                                saved_syn->tcp_hdrlen;
                }
        }

        *start = hdr_start;
        return ret;
}

BPF_CALL_5(bpf_sock_ops_getsockopt, struct bpf_sock_ops_kern *, bpf_sock,
           int, level, int, optname, char *, optval, int, optlen)
{
        if (!is_locked_tcp_sock_ops(bpf_sock))
                return -EOPNOTSUPP;

        if (IS_ENABLED(CONFIG_INET) && level == SOL_TCP &&
            optname >= TCP_BPF_SYN && optname <= TCP_BPF_SYN_MAC) {
                int ret, copy_len = 0;
                const u8 *start;

                ret = bpf_sock_ops_get_syn(bpf_sock, optname, &start);
                if (ret > 0) {
                        copy_len = ret;
                        if (optlen < copy_len) {
                                copy_len = optlen;
                                ret = -ENOSPC;
                        }

                        memcpy(optval, start, copy_len);
                }

                /* Zero out unused buffer at the end */
                memset(optval + copy_len, 0, optlen - copy_len);

                return ret;
        }

        return _bpf_getsockopt(bpf_sock->sk, level, optname, optval, optlen);
}

static const struct bpf_func_proto bpf_sock_ops_getsockopt_proto = {
        .func           = bpf_sock_ops_getsockopt,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
        .arg4_type      = ARG_PTR_TO_UNINIT_MEM,
        .arg5_type      = ARG_CONST_SIZE,
};

BPF_CALL_2(bpf_sock_ops_cb_flags_set, struct bpf_sock_ops_kern *, bpf_sock,
           int, argval)
{
        struct sock *sk = bpf_sock->sk;
        int val = argval & BPF_SOCK_OPS_ALL_CB_FLAGS;

        if (!is_locked_tcp_sock_ops(bpf_sock))
                return -EOPNOTSUPP;

        if (!IS_ENABLED(CONFIG_INET) || !sk_fullsock(sk))
                return -EINVAL;

        tcp_sk(sk)->bpf_sock_ops_cb_flags = val;

        return argval & (~BPF_SOCK_OPS_ALL_CB_FLAGS);
}

static const struct bpf_func_proto bpf_sock_ops_cb_flags_set_proto = {
        .func           = bpf_sock_ops_cb_flags_set,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
};

BPF_CALL_3(bpf_bind, struct bpf_sock_addr_kern *, ctx, struct sockaddr *, addr,
           int, addr_len)
{
#ifdef CONFIG_INET
        struct sock *sk = ctx->sk;
        u32 flags = BIND_FROM_BPF;
        int err;

        err = -EINVAL;
        if (addr_len < offsetofend(struct sockaddr, sa_family))
                return err;
        if (addr->sa_family == AF_INET) {
                if (addr_len < sizeof(struct sockaddr_in))
                        return err;
                if (((struct sockaddr_in *)addr)->sin_port == htons(0))
                        flags |= BIND_FORCE_ADDRESS_NO_PORT;
                return __inet_bind(sk, (struct sockaddr_unsized *)addr, addr_len, flags);
#if IS_ENABLED(CONFIG_IPV6)
        } else if (addr->sa_family == AF_INET6) {
                if (addr_len < SIN6_LEN_RFC2133)
                        return err;
                if (((struct sockaddr_in6 *)addr)->sin6_port == htons(0))
                        flags |= BIND_FORCE_ADDRESS_NO_PORT;

                return __inet6_bind(sk, (struct sockaddr_unsized *)addr,
                                    addr_len, flags);
#endif /* CONFIG_IPV6 */
        }
#endif /* CONFIG_INET */

        return -EAFNOSUPPORT;
}

static const struct bpf_func_proto bpf_bind_proto = {
        .func           = bpf_bind,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE,
};

#ifdef CONFIG_XFRM

#if (IS_BUILTIN(CONFIG_XFRM_INTERFACE) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF)) || \
    (IS_MODULE(CONFIG_XFRM_INTERFACE) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES))

struct metadata_dst __percpu *xfrm_bpf_md_dst;
EXPORT_SYMBOL_GPL(xfrm_bpf_md_dst);

#endif

BPF_CALL_5(bpf_skb_get_xfrm_state, struct sk_buff *, skb, u32, index,
           struct bpf_xfrm_state *, to, u32, size, u64, flags)
{
        const struct sec_path *sp = skb_sec_path(skb);
        const struct xfrm_state *x;

        if (!sp || unlikely(index >= sp->len || flags))
                goto err_clear;

        x = sp->xvec[index];

        if (unlikely(size != sizeof(struct bpf_xfrm_state)))
                goto err_clear;

        to->reqid = x->props.reqid;
        to->spi = x->id.spi;
        to->family = x->props.family;
        to->ext = 0;

        if (to->family == AF_INET6) {
                memcpy(to->remote_ipv6, x->props.saddr.a6,
                       sizeof(to->remote_ipv6));
        } else {
                to->remote_ipv4 = x->props.saddr.a4;
                memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3);
        }

        return 0;
err_clear:
        memset(to, 0, size);
        return -EINVAL;
}

static const struct bpf_func_proto bpf_skb_get_xfrm_state_proto = {
        .func           = bpf_skb_get_xfrm_state,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_PTR_TO_UNINIT_MEM,
        .arg4_type      = ARG_CONST_SIZE,
        .arg5_type      = ARG_ANYTHING,
};
#endif

#if IS_ENABLED(CONFIG_INET) || IS_ENABLED(CONFIG_IPV6)
static int bpf_fib_set_fwd_params(struct bpf_fib_lookup *params, u32 mtu)
{
        params->h_vlan_TCI = 0;
        params->h_vlan_proto = 0;
        if (mtu)
                params->mtu_result = mtu; /* union with tot_len */

        return 0;
}
#endif

#if IS_ENABLED(CONFIG_INET)
static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
                               u32 flags, bool check_mtu)
{
        struct neighbour *neigh = NULL;
        struct fib_nh_common *nhc;
        struct in_device *in_dev;
        struct net_device *dev;
        struct fib_result res;
        struct flowi4 fl4 = {};
        u32 mtu = 0;
        int err;

        dev = dev_get_by_index_rcu(net, params->ifindex);
        if (unlikely(!dev))
                return -ENODEV;

        /* verify forwarding is enabled on this interface */
        in_dev = __in_dev_get_rcu(dev);
        if (unlikely(!in_dev || !IN_DEV_FORWARD(in_dev)))
                return BPF_FIB_LKUP_RET_FWD_DISABLED;

        if (flags & BPF_FIB_LOOKUP_OUTPUT) {
                fl4.flowi4_iif = 1;
                fl4.flowi4_oif = params->ifindex;
        } else {
                fl4.flowi4_iif = params->ifindex;
                fl4.flowi4_oif = 0;
        }
        fl4.flowi4_dscp = inet_dsfield_to_dscp(params->tos);
        fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
        fl4.flowi4_flags = 0;

        fl4.flowi4_proto = params->l4_protocol;
        fl4.daddr = params->ipv4_dst;
        fl4.saddr = params->ipv4_src;
        fl4.fl4_sport = params->sport;
        fl4.fl4_dport = params->dport;
        fl4.flowi4_multipath_hash = 0;

        if (flags & BPF_FIB_LOOKUP_DIRECT) {
                u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
                struct fib_table *tb;

                if (flags & BPF_FIB_LOOKUP_TBID) {
                        tbid = params->tbid;
                        /* zero out for vlan output */
                        params->tbid = 0;
                }

                tb = fib_get_table(net, tbid);
                if (unlikely(!tb))
                        return BPF_FIB_LKUP_RET_NOT_FWDED;

                err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF);
        } else {
                if (flags & BPF_FIB_LOOKUP_MARK)
                        fl4.flowi4_mark = params->mark;
                else
                        fl4.flowi4_mark = 0;
                fl4.flowi4_secid = 0;
                fl4.flowi4_tun_key.tun_id = 0;
                fl4.flowi4_uid = sock_net_uid(net, NULL);

                err = fib_lookup(net, &fl4, &res, FIB_LOOKUP_NOREF);
        }

        if (err) {
                /* map fib lookup errors to RTN_ type */
                if (err == -EINVAL)
                        return BPF_FIB_LKUP_RET_BLACKHOLE;
                if (err == -EHOSTUNREACH)
                        return BPF_FIB_LKUP_RET_UNREACHABLE;
                if (err == -EACCES)
                        return BPF_FIB_LKUP_RET_PROHIBIT;

                return BPF_FIB_LKUP_RET_NOT_FWDED;
        }

        if (res.type != RTN_UNICAST)
                return BPF_FIB_LKUP_RET_NOT_FWDED;

        if (fib_info_num_path(res.fi) > 1)
                fib_select_path(net, &res, &fl4, NULL);

        if (check_mtu) {
                mtu = ip_mtu_from_fib_result(&res, params->ipv4_dst);
                if (params->tot_len > mtu) {
                        params->mtu_result = mtu; /* union with tot_len */
                        return BPF_FIB_LKUP_RET_FRAG_NEEDED;
                }
        }

        nhc = res.nhc;

        /* do not handle lwt encaps right now */
        if (nhc->nhc_lwtstate)
                return BPF_FIB_LKUP_RET_UNSUPP_LWT;

        dev = nhc->nhc_dev;

        params->rt_metric = res.fi->fib_priority;
        params->ifindex = dev->ifindex;

        if (flags & BPF_FIB_LOOKUP_SRC)
                params->ipv4_src = fib_result_prefsrc(net, &res);

        /* xdp and cls_bpf programs are run in RCU-bh so
         * rcu_read_lock_bh is not needed here
         */
        if (likely(nhc->nhc_gw_family != AF_INET6)) {
                if (nhc->nhc_gw_family)
                        params->ipv4_dst = nhc->nhc_gw.ipv4;
        } else {
                struct in6_addr *dst = (struct in6_addr *)params->ipv6_dst;

                params->family = AF_INET6;
                *dst = nhc->nhc_gw.ipv6;
        }

        if (flags & BPF_FIB_LOOKUP_SKIP_NEIGH)
                goto set_fwd_params;

        if (likely(nhc->nhc_gw_family != AF_INET6))
                neigh = __ipv4_neigh_lookup_noref(dev,
                                                  (__force u32)params->ipv4_dst);
        else if (IS_ENABLED(CONFIG_IPV6))
                neigh = __ipv6_neigh_lookup_noref(dev, params->ipv6_dst);

        if (!neigh || !(READ_ONCE(neigh->nud_state) & NUD_VALID))
                return BPF_FIB_LKUP_RET_NO_NEIGH;
        memcpy(params->dmac, neigh->ha, ETH_ALEN);
        memcpy(params->smac, dev->dev_addr, ETH_ALEN);

set_fwd_params:
        return bpf_fib_set_fwd_params(params, mtu);
}
#endif

#if IS_ENABLED(CONFIG_IPV6)
static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
                               u32 flags, bool check_mtu)
{
        struct in6_addr *src = (struct in6_addr *) params->ipv6_src;
        struct in6_addr *dst = (struct in6_addr *) params->ipv6_dst;
        struct fib6_result res = {};
        struct neighbour *neigh;
        struct net_device *dev;
        struct inet6_dev *idev;
        struct flowi6 fl6 = {};
        int strict = 0;
        int oif, err;
        u32 mtu = 0;

        /* link local addresses are never forwarded */
        if (rt6_need_strict(dst) || rt6_need_strict(src))
                return BPF_FIB_LKUP_RET_NOT_FWDED;

        dev = dev_get_by_index_rcu(net, params->ifindex);
        if (unlikely(!dev))
                return -ENODEV;

        idev = __in6_dev_get_safely(dev);
        if (unlikely(!idev || !READ_ONCE(idev->cnf.forwarding)))
                return BPF_FIB_LKUP_RET_FWD_DISABLED;

        if (flags & BPF_FIB_LOOKUP_OUTPUT) {
                fl6.flowi6_iif = 1;
                oif = fl6.flowi6_oif = params->ifindex;
        } else {
                oif = fl6.flowi6_iif = params->ifindex;
                fl6.flowi6_oif = 0;
                strict = RT6_LOOKUP_F_HAS_SADDR;
        }
        fl6.flowlabel = params->flowinfo;
        fl6.flowi6_scope = 0;
        fl6.flowi6_flags = 0;
        fl6.mp_hash = 0;

        fl6.flowi6_proto = params->l4_protocol;
        fl6.daddr = *dst;
        fl6.saddr = *src;
        fl6.fl6_sport = params->sport;
        fl6.fl6_dport = params->dport;

        if (flags & BPF_FIB_LOOKUP_DIRECT) {
                u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
                struct fib6_table *tb;

                if (flags & BPF_FIB_LOOKUP_TBID) {
                        tbid = params->tbid;
                        /* zero out for vlan output */
                        params->tbid = 0;
                }

                tb = fib6_get_table(net, tbid);
                if (unlikely(!tb))
                        return BPF_FIB_LKUP_RET_NOT_FWDED;

                err = fib6_table_lookup(net, tb, oif, &fl6, &res, strict);
        } else {
                if (flags & BPF_FIB_LOOKUP_MARK)
                        fl6.flowi6_mark = params->mark;
                else
                        fl6.flowi6_mark = 0;
                fl6.flowi6_secid = 0;
                fl6.flowi6_tun_key.tun_id = 0;
                fl6.flowi6_uid = sock_net_uid(net, NULL);

                err = fib6_lookup(net, oif, &fl6, &res, strict);
        }

        if (unlikely(err || IS_ERR_OR_NULL(res.f6i) ||
                     res.f6i == net->ipv6.fib6_null_entry))
                return BPF_FIB_LKUP_RET_NOT_FWDED;

        switch (res.fib6_type) {
        /* only unicast is forwarded */
        case RTN_UNICAST:
                break;
        case RTN_BLACKHOLE:
                return BPF_FIB_LKUP_RET_BLACKHOLE;
        case RTN_UNREACHABLE:
                return BPF_FIB_LKUP_RET_UNREACHABLE;
        case RTN_PROHIBIT:
                return BPF_FIB_LKUP_RET_PROHIBIT;
        default:
                return BPF_FIB_LKUP_RET_NOT_FWDED;
        }

        fib6_select_path(net, &res, &fl6, fl6.flowi6_oif,
                         fl6.flowi6_oif != 0, NULL, strict);

        if (check_mtu) {
                mtu = ip6_mtu_from_fib6(&res, dst, src);
                if (params->tot_len > mtu) {
                        params->mtu_result = mtu; /* union with tot_len */
                        return BPF_FIB_LKUP_RET_FRAG_NEEDED;
                }
        }

        if (res.nh->fib_nh_lws)
                return BPF_FIB_LKUP_RET_UNSUPP_LWT;

        if (res.nh->fib_nh_gw_family)
                *dst = res.nh->fib_nh_gw6;

        dev = res.nh->fib_nh_dev;
        params->rt_metric = res.f6i->fib6_metric;
        params->ifindex = dev->ifindex;

        if (flags & BPF_FIB_LOOKUP_SRC) {
                if (res.f6i->fib6_prefsrc.plen) {
                        *src = res.f6i->fib6_prefsrc.addr;
                } else {
                        err = ipv6_dev_get_saddr(net, dev, &fl6.daddr, 0, src);
                        if (err)
                                return BPF_FIB_LKUP_RET_NO_SRC_ADDR;
                }
        }

        if (flags & BPF_FIB_LOOKUP_SKIP_NEIGH)
                goto set_fwd_params;

        /* xdp and cls_bpf programs are run in RCU-bh so rcu_read_lock_bh is
         * not needed here.
         */
        neigh = __ipv6_neigh_lookup_noref(dev, dst);
        if (!neigh || !(READ_ONCE(neigh->nud_state) & NUD_VALID))
                return BPF_FIB_LKUP_RET_NO_NEIGH;
        memcpy(params->dmac, neigh->ha, ETH_ALEN);
        memcpy(params->smac, dev->dev_addr, ETH_ALEN);

set_fwd_params:
        return bpf_fib_set_fwd_params(params, mtu);
}
#endif

#define BPF_FIB_LOOKUP_MASK (BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT | \
                             BPF_FIB_LOOKUP_SKIP_NEIGH | BPF_FIB_LOOKUP_TBID | \
                             BPF_FIB_LOOKUP_SRC | BPF_FIB_LOOKUP_MARK)

BPF_CALL_4(bpf_xdp_fib_lookup, struct xdp_buff *, ctx,
           struct bpf_fib_lookup *, params, int, plen, u32, flags)
{
        if (plen < sizeof(*params))
                return -EINVAL;

        if (flags & ~BPF_FIB_LOOKUP_MASK)
                return -EINVAL;

        switch (params->family) {
#if IS_ENABLED(CONFIG_INET)
        case AF_INET:
                return bpf_ipv4_fib_lookup(dev_net(ctx->rxq->dev), params,
                                           flags, true);
#endif
#if IS_ENABLED(CONFIG_IPV6)
        case AF_INET6:
                return bpf_ipv6_fib_lookup(dev_net(ctx->rxq->dev), params,
                                           flags, true);
#endif
        }
        return -EAFNOSUPPORT;
}

static const struct bpf_func_proto bpf_xdp_fib_lookup_proto = {
        .func           = bpf_xdp_fib_lookup,
        .gpl_only       = true,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_WRITE,
        .arg3_type      = ARG_CONST_SIZE,
        .arg4_type      = ARG_ANYTHING,
};

BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb,
           struct bpf_fib_lookup *, params, int, plen, u32, flags)
{
        struct net *net = dev_net(skb->dev);
        int rc = -EAFNOSUPPORT;
        bool check_mtu = false;

        if (plen < sizeof(*params))
                return -EINVAL;

        if (flags & ~BPF_FIB_LOOKUP_MASK)
                return -EINVAL;

        if (params->tot_len)
                check_mtu = true;

        switch (params->family) {
#if IS_ENABLED(CONFIG_INET)
        case AF_INET:
                rc = bpf_ipv4_fib_lookup(net, params, flags, check_mtu);
                break;
#endif
#if IS_ENABLED(CONFIG_IPV6)
        case AF_INET6:
                rc = bpf_ipv6_fib_lookup(net, params, flags, check_mtu);
                break;
#endif
        }

        if (rc == BPF_FIB_LKUP_RET_SUCCESS && !check_mtu) {
                struct net_device *dev;

                /* When tot_len isn't provided by user, check skb
                 * against MTU of FIB lookup resulting net_device
                 */
                dev = dev_get_by_index_rcu(net, params->ifindex);
                if (unlikely(!dev))
                        return -ENODEV;
                if (!is_skb_forwardable(dev, skb))
                        rc = BPF_FIB_LKUP_RET_FRAG_NEEDED;

                params->mtu_result = dev->mtu; /* union with tot_len */
        }

        return rc;
}

static const struct bpf_func_proto bpf_skb_fib_lookup_proto = {
        .func           = bpf_skb_fib_lookup,
        .gpl_only       = true,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_WRITE,
        .arg3_type      = ARG_CONST_SIZE,
        .arg4_type      = ARG_ANYTHING,
};

static struct net_device *__dev_via_ifindex(struct net_device *dev_curr,
                                            u32 ifindex)
{
        struct net *netns = dev_net(dev_curr);

        /* Non-redirect use-cases can use ifindex=0 and save ifindex lookup */
        if (ifindex == 0)
                return dev_curr;

        return dev_get_by_index_rcu(netns, ifindex);
}

BPF_CALL_5(bpf_skb_check_mtu, struct sk_buff *, skb,
           u32, ifindex, u32 *, mtu_len, s32, len_diff, u64, flags)
{
        int ret = BPF_MTU_CHK_RET_FRAG_NEEDED;
        struct net_device *dev = skb->dev;
        int mtu, dev_len, skb_len;

        if (unlikely(flags & ~(BPF_MTU_CHK_SEGS)))
                return -EINVAL;
        if (unlikely(flags & BPF_MTU_CHK_SEGS && (len_diff || *mtu_len)))
                return -EINVAL;

        dev = __dev_via_ifindex(dev, ifindex);
        if (unlikely(!dev))
                return -ENODEV;

        mtu = READ_ONCE(dev->mtu);
        dev_len = mtu + dev->hard_header_len;

        /* If set use *mtu_len as input, L3 as iph->tot_len (like fib_lookup) */
        skb_len = *mtu_len ? *mtu_len + dev->hard_header_len : skb->len;

        skb_len += len_diff; /* minus result pass check */
        if (skb_len <= dev_len) {
                ret = BPF_MTU_CHK_RET_SUCCESS;
                goto out;
        }
        /* At this point, skb->len exceed MTU, but as it include length of all
         * segments, it can still be below MTU.  The SKB can possibly get
         * re-segmented in transmit path (see validate_xmit_skb).  Thus, user
         * must choose if segs are to be MTU checked.
         */
        if (skb_is_gso(skb)) {
                ret = BPF_MTU_CHK_RET_SUCCESS;
                if (flags & BPF_MTU_CHK_SEGS) {
                        if (!skb_transport_header_was_set(skb))
                                return -EINVAL;
                        if (!skb_gso_validate_network_len(skb, mtu))
                                ret = BPF_MTU_CHK_RET_SEGS_TOOBIG;
                }
        }
out:
        *mtu_len = mtu;
        return ret;
}

BPF_CALL_5(bpf_xdp_check_mtu, struct xdp_buff *, xdp,
           u32, ifindex, u32 *, mtu_len, s32, len_diff, u64, flags)
{
        struct net_device *dev = xdp->rxq->dev;
        int xdp_len = xdp->data_end - xdp->data;
        int ret = BPF_MTU_CHK_RET_SUCCESS;
        int mtu, dev_len;

        /* XDP variant doesn't support multi-buffer segment check (yet) */
        if (unlikely(flags))
                return -EINVAL;

        dev = __dev_via_ifindex(dev, ifindex);
        if (unlikely(!dev))
                return -ENODEV;

        mtu = READ_ONCE(dev->mtu);
        dev_len = mtu + dev->hard_header_len;

        /* Use *mtu_len as input, L3 as iph->tot_len (like fib_lookup) */
        if (*mtu_len)
                xdp_len = *mtu_len + dev->hard_header_len;

        xdp_len += len_diff; /* minus result pass check */
        if (xdp_len > dev_len)
                ret = BPF_MTU_CHK_RET_FRAG_NEEDED;

        *mtu_len = mtu;
        return ret;
}

static const struct bpf_func_proto bpf_skb_check_mtu_proto = {
        .func           = bpf_skb_check_mtu,
        .gpl_only       = true,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_WRITE | MEM_ALIGNED,
        .arg3_size      = sizeof(u32),
        .arg4_type      = ARG_ANYTHING,
        .arg5_type      = ARG_ANYTHING,
};

static const struct bpf_func_proto bpf_xdp_check_mtu_proto = {
        .func           = bpf_xdp_check_mtu,
        .gpl_only       = true,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_WRITE | MEM_ALIGNED,
        .arg3_size      = sizeof(u32),
        .arg4_type      = ARG_ANYTHING,
        .arg5_type      = ARG_ANYTHING,
};

#if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
static int bpf_push_seg6_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len)
{
        int err;
        struct ipv6_sr_hdr *srh = (struct ipv6_sr_hdr *)hdr;

        if (!seg6_validate_srh(srh, len, false))
                return -EINVAL;

        switch (type) {
        case BPF_LWT_ENCAP_SEG6_INLINE:
                if (skb->protocol != htons(ETH_P_IPV6))
                        return -EBADMSG;

                err = seg6_do_srh_inline(skb, srh);
                break;
        case BPF_LWT_ENCAP_SEG6:
                skb_reset_inner_headers(skb);
                skb->encapsulation = 1;
                err = seg6_do_srh_encap(skb, srh, IPPROTO_IPV6);
                break;
        default:
                return -EINVAL;
        }

        bpf_compute_data_pointers(skb);
        if (err)
                return err;

        skb_set_transport_header(skb, sizeof(struct ipv6hdr));

        return seg6_lookup_nexthop(skb, NULL, 0);
}
#endif /* CONFIG_IPV6_SEG6_BPF */

#if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
static int bpf_push_ip_encap(struct sk_buff *skb, void *hdr, u32 len,
                             bool ingress)
{
        return bpf_lwt_push_ip_encap(skb, hdr, len, ingress);
}
#endif

BPF_CALL_4(bpf_lwt_in_push_encap, struct sk_buff *, skb, u32, type, void *, hdr,
           u32, len)
{
        switch (type) {
#if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
        case BPF_LWT_ENCAP_SEG6:
        case BPF_LWT_ENCAP_SEG6_INLINE:
                return bpf_push_seg6_encap(skb, type, hdr, len);
#endif
#if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
        case BPF_LWT_ENCAP_IP:
                return bpf_push_ip_encap(skb, hdr, len, true /* ingress */);
#endif
        default:
                return -EINVAL;
        }
}

BPF_CALL_4(bpf_lwt_xmit_push_encap, struct sk_buff *, skb, u32, type,
           void *, hdr, u32, len)
{
        switch (type) {
#if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
        case BPF_LWT_ENCAP_IP:
                return bpf_push_ip_encap(skb, hdr, len, false /* egress */);
#endif
        default:
                return -EINVAL;
        }
}

static const struct bpf_func_proto bpf_lwt_in_push_encap_proto = {
        .func           = bpf_lwt_in_push_encap,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg4_type      = ARG_CONST_SIZE
};

static const struct bpf_func_proto bpf_lwt_xmit_push_encap_proto = {
        .func           = bpf_lwt_xmit_push_encap,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg4_type      = ARG_CONST_SIZE
};

#if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
BPF_CALL_4(bpf_lwt_seg6_store_bytes, struct sk_buff *, skb, u32, offset,
           const void *, from, u32, len)
{
        struct seg6_bpf_srh_state *srh_state =
                this_cpu_ptr(&seg6_bpf_srh_states);
        struct ipv6_sr_hdr *srh = srh_state->srh;
        void *srh_tlvs, *srh_end, *ptr;
        int srhoff = 0;

        lockdep_assert_held(&srh_state->bh_lock);
        if (srh == NULL)
                return -EINVAL;

        srh_tlvs = (void *)((char *)srh + ((srh->first_segment + 1) << 4));
        srh_end = (void *)((char *)srh + sizeof(*srh) + srh_state->hdrlen);

        ptr = skb->data + offset;
        if (ptr >= srh_tlvs && ptr + len <= srh_end)
                srh_state->valid = false;
        else if (ptr < (void *)&srh->flags ||
                 ptr + len > (void *)&srh->segments)
                return -EFAULT;

        if (unlikely(bpf_try_make_writable(skb, offset + len)))
                return -EFAULT;
        if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
                return -EINVAL;
        srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);

        memcpy(skb->data + offset, from, len);
        return 0;
}

static const struct bpf_func_proto bpf_lwt_seg6_store_bytes_proto = {
        .func           = bpf_lwt_seg6_store_bytes,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg4_type      = ARG_CONST_SIZE
};

static void bpf_update_srh_state(struct sk_buff *skb)
{
        struct seg6_bpf_srh_state *srh_state =
                this_cpu_ptr(&seg6_bpf_srh_states);
        int srhoff = 0;

        if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) {
                srh_state->srh = NULL;
        } else {
                srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
                srh_state->hdrlen = srh_state->srh->hdrlen << 3;
                srh_state->valid = true;
        }
}

BPF_CALL_4(bpf_lwt_seg6_action, struct sk_buff *, skb,
           u32, action, void *, param, u32, param_len)
{
        struct seg6_bpf_srh_state *srh_state =
                this_cpu_ptr(&seg6_bpf_srh_states);
        int hdroff = 0;
        int err;

        lockdep_assert_held(&srh_state->bh_lock);
        switch (action) {
        case SEG6_LOCAL_ACTION_END_X:
                if (!seg6_bpf_has_valid_srh(skb))
                        return -EBADMSG;
                if (param_len != sizeof(struct in6_addr))
                        return -EINVAL;
                return seg6_lookup_nexthop(skb, (struct in6_addr *)param, 0);
        case SEG6_LOCAL_ACTION_END_T:
                if (!seg6_bpf_has_valid_srh(skb))
                        return -EBADMSG;
                if (param_len != sizeof(int))
                        return -EINVAL;
                return seg6_lookup_nexthop(skb, NULL, *(int *)param);
        case SEG6_LOCAL_ACTION_END_DT6:
                if (!seg6_bpf_has_valid_srh(skb))
                        return -EBADMSG;
                if (param_len != sizeof(int))
                        return -EINVAL;

                if (ipv6_find_hdr(skb, &hdroff, IPPROTO_IPV6, NULL, NULL) < 0)
                        return -EBADMSG;
                if (!pskb_pull(skb, hdroff))
                        return -EBADMSG;

                skb_postpull_rcsum(skb, skb_network_header(skb), hdroff);
                skb_reset_network_header(skb);
                skb_reset_transport_header(skb);
                skb->encapsulation = 0;

                bpf_compute_data_pointers(skb);
                bpf_update_srh_state(skb);
                return seg6_lookup_nexthop(skb, NULL, *(int *)param);
        case SEG6_LOCAL_ACTION_END_B6:
                if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
                        return -EBADMSG;
                err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6_INLINE,
                                          param, param_len);
                if (!err)
                        bpf_update_srh_state(skb);

                return err;
        case SEG6_LOCAL_ACTION_END_B6_ENCAP:
                if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
                        return -EBADMSG;
                err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6,
                                          param, param_len);
                if (!err)
                        bpf_update_srh_state(skb);

                return err;
        default:
                return -EINVAL;
        }
}

static const struct bpf_func_proto bpf_lwt_seg6_action_proto = {
        .func           = bpf_lwt_seg6_action,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg4_type      = ARG_CONST_SIZE
};

BPF_CALL_3(bpf_lwt_seg6_adjust_srh, struct sk_buff *, skb, u32, offset,
           s32, len)
{
        struct seg6_bpf_srh_state *srh_state =
                this_cpu_ptr(&seg6_bpf_srh_states);
        struct ipv6_sr_hdr *srh = srh_state->srh;
        void *srh_end, *srh_tlvs, *ptr;
        struct ipv6hdr *hdr;
        int srhoff = 0;
        int ret;

        lockdep_assert_held(&srh_state->bh_lock);
        if (unlikely(srh == NULL))
                return -EINVAL;

        srh_tlvs = (void *)((unsigned char *)srh + sizeof(*srh) +
                        ((srh->first_segment + 1) << 4));
        srh_end = (void *)((unsigned char *)srh + sizeof(*srh) +
                        srh_state->hdrlen);
        ptr = skb->data + offset;

        if (unlikely(ptr < srh_tlvs || ptr > srh_end))
                return -EFAULT;
        if (unlikely(len < 0 && (void *)((char *)ptr - len) > srh_end))
                return -EFAULT;

        if (len > 0) {
                ret = skb_cow_head(skb, len);
                if (unlikely(ret < 0))
                        return ret;

                ret = bpf_skb_net_hdr_push(skb, offset, len);
        } else {
                ret = bpf_skb_net_hdr_pop(skb, offset, -1 * len);
        }

        bpf_compute_data_pointers(skb);
        if (unlikely(ret < 0))
                return ret;

        hdr = (struct ipv6hdr *)skb->data;
        hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));

        if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
                return -EINVAL;
        srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
        srh_state->hdrlen += len;
        srh_state->valid = false;
        return 0;
}

static const struct bpf_func_proto bpf_lwt_seg6_adjust_srh_proto = {
        .func           = bpf_lwt_seg6_adjust_srh,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
};
#endif /* CONFIG_IPV6_SEG6_BPF */

#ifdef CONFIG_INET
static struct sock *sk_lookup(struct net *net, struct bpf_sock_tuple *tuple,
                              int dif, int sdif, u8 family, u8 proto)
{
        bool refcounted = false;
        struct sock *sk = NULL;

        if (family == AF_INET) {
                __be32 src4 = tuple->ipv4.saddr;
                __be32 dst4 = tuple->ipv4.daddr;

                if (proto == IPPROTO_TCP)
                        sk = __inet_lookup(net, NULL, 0,
                                           src4, tuple->ipv4.sport,
                                           dst4, tuple->ipv4.dport,
                                           dif, sdif, &refcounted);
                else
                        sk = __udp4_lib_lookup(net, src4, tuple->ipv4.sport,
                                               dst4, tuple->ipv4.dport,
                                               dif, sdif, NULL);
#if IS_ENABLED(CONFIG_IPV6)
        } else {
                struct in6_addr *src6 = (struct in6_addr *)&tuple->ipv6.saddr;
                struct in6_addr *dst6 = (struct in6_addr *)&tuple->ipv6.daddr;

                if (proto == IPPROTO_TCP)
                        sk = __inet6_lookup(net, NULL, 0,
                                            src6, tuple->ipv6.sport,
                                            dst6, ntohs(tuple->ipv6.dport),
                                            dif, sdif, &refcounted);
                else if (likely(ipv6_mod_enabled()))
                        sk = __udp6_lib_lookup(net, src6, tuple->ipv6.sport,
                                               dst6, tuple->ipv6.dport,
                                               dif, sdif, NULL);
#endif
        }

        if (unlikely(sk && !refcounted && !sock_flag(sk, SOCK_RCU_FREE))) {
                WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
                sk = NULL;
        }
        return sk;
}

/* bpf_skc_lookup performs the core lookup for different types of sockets,
 * taking a reference on the socket if it doesn't have the flag SOCK_RCU_FREE.
 */
static struct sock *
__bpf_skc_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
                 struct net *caller_net, u32 ifindex, u8 proto, u64 netns_id,
                 u64 flags, int sdif)
{
        struct sock *sk = NULL;
        struct net *net;
        u8 family;

        if (len == sizeof(tuple->ipv4))
                family = AF_INET;
        else if (len == sizeof(tuple->ipv6))
                family = AF_INET6;
        else
                return NULL;

        if (unlikely(flags || !((s32)netns_id < 0 || netns_id <= S32_MAX)))
                goto out;

        if (sdif < 0) {
                if (family == AF_INET)
                        sdif = inet_sdif(skb);
                else
                        sdif = inet6_sdif(skb);
        }

        if ((s32)netns_id < 0) {
                net = caller_net;
                sk = sk_lookup(net, tuple, ifindex, sdif, family, proto);
        } else {
                net = get_net_ns_by_id(caller_net, netns_id);
                if (unlikely(!net))
                        goto out;
                sk = sk_lookup(net, tuple, ifindex, sdif, family, proto);
                put_net(net);
        }

out:
        return sk;
}

static struct sock *
__bpf_sk_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
                struct net *caller_net, u32 ifindex, u8 proto, u64 netns_id,
                u64 flags, int sdif)
{
        struct sock *sk = __bpf_skc_lookup(skb, tuple, len, caller_net,
                                           ifindex, proto, netns_id, flags,
                                           sdif);

        if (sk) {
                struct sock *sk2 = sk_to_full_sk(sk);

                /* sk_to_full_sk() may return (sk)->rsk_listener, so make sure the original sk
                 * sock refcnt is decremented to prevent a request_sock leak.
                 */
                if (sk2 != sk) {
                        sock_gen_put(sk);
                        /* Ensure there is no need to bump sk2 refcnt */
                        if (unlikely(sk2 && !sock_flag(sk2, SOCK_RCU_FREE))) {
                                WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
                                return NULL;
                        }
                        sk = sk2;
                }
        }

        return sk;
}

static struct sock *
bpf_skc_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
               u8 proto, u64 netns_id, u64 flags)
{
        struct net *caller_net;
        int ifindex;

        if (skb->dev) {
                caller_net = dev_net(skb->dev);
                ifindex = skb->dev->ifindex;
        } else {
                caller_net = sock_net(skb->sk);
                ifindex = 0;
        }

        return __bpf_skc_lookup(skb, tuple, len, caller_net, ifindex, proto,
                                netns_id, flags, -1);
}

static struct sock *
bpf_sk_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
              u8 proto, u64 netns_id, u64 flags)
{
        struct sock *sk = bpf_skc_lookup(skb, tuple, len, proto, netns_id,
                                         flags);

        if (sk) {
                struct sock *sk2 = sk_to_full_sk(sk);

                /* sk_to_full_sk() may return (sk)->rsk_listener, so make sure the original sk
                 * sock refcnt is decremented to prevent a request_sock leak.
                 */
                if (sk2 != sk) {
                        sock_gen_put(sk);
                        /* Ensure there is no need to bump sk2 refcnt */
                        if (unlikely(sk2 && !sock_flag(sk2, SOCK_RCU_FREE))) {
                                WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
                                return NULL;
                        }
                        sk = sk2;
                }
        }

        return sk;
}

BPF_CALL_5(bpf_skc_lookup_tcp, struct sk_buff *, skb,
           struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
{
        return (unsigned long)bpf_skc_lookup(skb, tuple, len, IPPROTO_TCP,
                                             netns_id, flags);
}

static const struct bpf_func_proto bpf_skc_lookup_tcp_proto = {
        .func           = bpf_skc_lookup_tcp,
        .gpl_only       = false,
        .pkt_access     = true,
        .ret_type       = RET_PTR_TO_SOCK_COMMON_OR_NULL,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
        .arg4_type      = ARG_ANYTHING,
        .arg5_type      = ARG_ANYTHING,
};

BPF_CALL_5(bpf_sk_lookup_tcp, struct sk_buff *, skb,
           struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
{
        return (unsigned long)bpf_sk_lookup(skb, tuple, len, IPPROTO_TCP,
                                            netns_id, flags);
}

static const struct bpf_func_proto bpf_sk_lookup_tcp_proto = {
        .func           = bpf_sk_lookup_tcp,
        .gpl_only       = false,
        .pkt_access     = true,
        .ret_type       = RET_PTR_TO_SOCKET_OR_NULL,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
        .arg4_type      = ARG_ANYTHING,
        .arg5_type      = ARG_ANYTHING,
};

BPF_CALL_5(bpf_sk_lookup_udp, struct sk_buff *, skb,
           struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
{
        return (unsigned long)bpf_sk_lookup(skb, tuple, len, IPPROTO_UDP,
                                            netns_id, flags);
}

static const struct bpf_func_proto bpf_sk_lookup_udp_proto = {
        .func           = bpf_sk_lookup_udp,
        .gpl_only       = false,
        .pkt_access     = true,
        .ret_type       = RET_PTR_TO_SOCKET_OR_NULL,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
        .arg4_type      = ARG_ANYTHING,
        .arg5_type      = ARG_ANYTHING,
};

BPF_CALL_5(bpf_tc_skc_lookup_tcp, struct sk_buff *, skb,
           struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
{
        struct net_device *dev = skb->dev;
        int ifindex = dev->ifindex, sdif = dev_sdif(dev);
        struct net *caller_net = dev_net(dev);

        return (unsigned long)__bpf_skc_lookup(skb, tuple, len, caller_net,
                                               ifindex, IPPROTO_TCP, netns_id,
                                               flags, sdif);
}

static const struct bpf_func_proto bpf_tc_skc_lookup_tcp_proto = {
        .func           = bpf_tc_skc_lookup_tcp,
        .gpl_only       = false,
        .pkt_access     = true,
        .ret_type       = RET_PTR_TO_SOCK_COMMON_OR_NULL,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
        .arg4_type      = ARG_ANYTHING,
        .arg5_type      = ARG_ANYTHING,
};

BPF_CALL_5(bpf_tc_sk_lookup_tcp, struct sk_buff *, skb,
           struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
{
        struct net_device *dev = skb->dev;
        int ifindex = dev->ifindex, sdif = dev_sdif(dev);
        struct net *caller_net = dev_net(dev);

        return (unsigned long)__bpf_sk_lookup(skb, tuple, len, caller_net,
                                              ifindex, IPPROTO_TCP, netns_id,
                                              flags, sdif);
}

static const struct bpf_func_proto bpf_tc_sk_lookup_tcp_proto = {
        .func           = bpf_tc_sk_lookup_tcp,
        .gpl_only       = false,
        .pkt_access     = true,
        .ret_type       = RET_PTR_TO_SOCKET_OR_NULL,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
        .arg4_type      = ARG_ANYTHING,
        .arg5_type      = ARG_ANYTHING,
};

BPF_CALL_5(bpf_tc_sk_lookup_udp, struct sk_buff *, skb,
           struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
{
        struct net_device *dev = skb->dev;
        int ifindex = dev->ifindex, sdif = dev_sdif(dev);
        struct net *caller_net = dev_net(dev);

        return (unsigned long)__bpf_sk_lookup(skb, tuple, len, caller_net,
                                              ifindex, IPPROTO_UDP, netns_id,
                                              flags, sdif);
}

static const struct bpf_func_proto bpf_tc_sk_lookup_udp_proto = {
        .func           = bpf_tc_sk_lookup_udp,
        .gpl_only       = false,
        .pkt_access     = true,
        .ret_type       = RET_PTR_TO_SOCKET_OR_NULL,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
        .arg4_type      = ARG_ANYTHING,
        .arg5_type      = ARG_ANYTHING,
};

BPF_CALL_1(bpf_sk_release, struct sock *, sk)
{
        if (sk && sk_is_refcounted(sk))
                sock_gen_put(sk);
        return 0;
}

static const struct bpf_func_proto bpf_sk_release_proto = {
        .func           = bpf_sk_release,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON | OBJ_RELEASE,
};

BPF_CALL_5(bpf_xdp_sk_lookup_udp, struct xdp_buff *, ctx,
           struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
{
        struct net_device *dev = ctx->rxq->dev;
        int ifindex = dev->ifindex, sdif = dev_sdif(dev);
        struct net *caller_net = dev_net(dev);

        return (unsigned long)__bpf_sk_lookup(NULL, tuple, len, caller_net,
                                              ifindex, IPPROTO_UDP, netns_id,
                                              flags, sdif);
}

static const struct bpf_func_proto bpf_xdp_sk_lookup_udp_proto = {
        .func           = bpf_xdp_sk_lookup_udp,
        .gpl_only       = false,
        .pkt_access     = true,
        .ret_type       = RET_PTR_TO_SOCKET_OR_NULL,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
        .arg4_type      = ARG_ANYTHING,
        .arg5_type      = ARG_ANYTHING,
};

BPF_CALL_5(bpf_xdp_skc_lookup_tcp, struct xdp_buff *, ctx,
           struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
{
        struct net_device *dev = ctx->rxq->dev;
        int ifindex = dev->ifindex, sdif = dev_sdif(dev);
        struct net *caller_net = dev_net(dev);

        return (unsigned long)__bpf_skc_lookup(NULL, tuple, len, caller_net,
                                               ifindex, IPPROTO_TCP, netns_id,
                                               flags, sdif);
}

static const struct bpf_func_proto bpf_xdp_skc_lookup_tcp_proto = {
        .func           = bpf_xdp_skc_lookup_tcp,
        .gpl_only       = false,
        .pkt_access     = true,
        .ret_type       = RET_PTR_TO_SOCK_COMMON_OR_NULL,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
        .arg4_type      = ARG_ANYTHING,
        .arg5_type      = ARG_ANYTHING,
};

BPF_CALL_5(bpf_xdp_sk_lookup_tcp, struct xdp_buff *, ctx,
           struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
{
        struct net_device *dev = ctx->rxq->dev;
        int ifindex = dev->ifindex, sdif = dev_sdif(dev);
        struct net *caller_net = dev_net(dev);

        return (unsigned long)__bpf_sk_lookup(NULL, tuple, len, caller_net,
                                              ifindex, IPPROTO_TCP, netns_id,
                                              flags, sdif);
}

static const struct bpf_func_proto bpf_xdp_sk_lookup_tcp_proto = {
        .func           = bpf_xdp_sk_lookup_tcp,
        .gpl_only       = false,
        .pkt_access     = true,
        .ret_type       = RET_PTR_TO_SOCKET_OR_NULL,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
        .arg4_type      = ARG_ANYTHING,
        .arg5_type      = ARG_ANYTHING,
};

BPF_CALL_5(bpf_sock_addr_skc_lookup_tcp, struct bpf_sock_addr_kern *, ctx,
           struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
{
        return (unsigned long)__bpf_skc_lookup(NULL, tuple, len,
                                               sock_net(ctx->sk), 0,
                                               IPPROTO_TCP, netns_id, flags,
                                               -1);
}

static const struct bpf_func_proto bpf_sock_addr_skc_lookup_tcp_proto = {
        .func           = bpf_sock_addr_skc_lookup_tcp,
        .gpl_only       = false,
        .ret_type       = RET_PTR_TO_SOCK_COMMON_OR_NULL,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
        .arg4_type      = ARG_ANYTHING,
        .arg5_type      = ARG_ANYTHING,
};

BPF_CALL_5(bpf_sock_addr_sk_lookup_tcp, struct bpf_sock_addr_kern *, ctx,
           struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
{
        return (unsigned long)__bpf_sk_lookup(NULL, tuple, len,
                                              sock_net(ctx->sk), 0, IPPROTO_TCP,
                                              netns_id, flags, -1);
}

static const struct bpf_func_proto bpf_sock_addr_sk_lookup_tcp_proto = {
        .func           = bpf_sock_addr_sk_lookup_tcp,
        .gpl_only       = false,
        .ret_type       = RET_PTR_TO_SOCKET_OR_NULL,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
        .arg4_type      = ARG_ANYTHING,
        .arg5_type      = ARG_ANYTHING,
};

BPF_CALL_5(bpf_sock_addr_sk_lookup_udp, struct bpf_sock_addr_kern *, ctx,
           struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
{
        return (unsigned long)__bpf_sk_lookup(NULL, tuple, len,
                                              sock_net(ctx->sk), 0, IPPROTO_UDP,
                                              netns_id, flags, -1);
}

static const struct bpf_func_proto bpf_sock_addr_sk_lookup_udp_proto = {
        .func           = bpf_sock_addr_sk_lookup_udp,
        .gpl_only       = false,
        .ret_type       = RET_PTR_TO_SOCKET_OR_NULL,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
        .arg4_type      = ARG_ANYTHING,
        .arg5_type      = ARG_ANYTHING,
};

bool bpf_tcp_sock_is_valid_access(int off, int size, enum bpf_access_type type,
                                  struct bpf_insn_access_aux *info)
{
        if (off < 0 || off >= offsetofend(struct bpf_tcp_sock,
                                          icsk_retransmits))
                return false;

        if (off % size != 0)
                return false;

        switch (off) {
        case offsetof(struct bpf_tcp_sock, bytes_received):
        case offsetof(struct bpf_tcp_sock, bytes_acked):
                return size == sizeof(__u64);
        default:
                return size == sizeof(__u32);
        }
}

u32 bpf_tcp_sock_convert_ctx_access(enum bpf_access_type type,
                                    const struct bpf_insn *si,
                                    struct bpf_insn *insn_buf,
                                    struct bpf_prog *prog, u32 *target_size)
{
        struct bpf_insn *insn = insn_buf;

#define BPF_TCP_SOCK_GET_COMMON(FIELD)                                  \
        do {                                                            \
                BUILD_BUG_ON(sizeof_field(struct tcp_sock, FIELD) >     \
                             sizeof_field(struct bpf_tcp_sock, FIELD)); \
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct tcp_sock, FIELD),\
                                      si->dst_reg, si->src_reg,         \
                                      offsetof(struct tcp_sock, FIELD)); \
        } while (0)

#define BPF_INET_SOCK_GET_COMMON(FIELD)                                 \
        do {                                                            \
                BUILD_BUG_ON(sizeof_field(struct inet_connection_sock,  \
                                          FIELD) >                      \
                             sizeof_field(struct bpf_tcp_sock, FIELD)); \
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(                 \
                                        struct inet_connection_sock,    \
                                        FIELD),                         \
                                      si->dst_reg, si->src_reg,         \
                                      offsetof(                         \
                                        struct inet_connection_sock,    \
                                        FIELD));                        \
        } while (0)

        BTF_TYPE_EMIT(struct bpf_tcp_sock);

        switch (si->off) {
        case offsetof(struct bpf_tcp_sock, rtt_min):
                BUILD_BUG_ON(sizeof_field(struct tcp_sock, rtt_min) !=
                             sizeof(struct minmax));
                BUILD_BUG_ON(sizeof(struct minmax) <
                             sizeof(struct minmax_sample));

                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
                                      offsetof(struct tcp_sock, rtt_min) +
                                      offsetof(struct minmax_sample, v));
                break;
        case offsetof(struct bpf_tcp_sock, snd_cwnd):
                BPF_TCP_SOCK_GET_COMMON(snd_cwnd);
                break;
        case offsetof(struct bpf_tcp_sock, srtt_us):
                BPF_TCP_SOCK_GET_COMMON(srtt_us);
                break;
        case offsetof(struct bpf_tcp_sock, snd_ssthresh):
                BPF_TCP_SOCK_GET_COMMON(snd_ssthresh);
                break;
        case offsetof(struct bpf_tcp_sock, rcv_nxt):
                BPF_TCP_SOCK_GET_COMMON(rcv_nxt);
                break;
        case offsetof(struct bpf_tcp_sock, snd_nxt):
                BPF_TCP_SOCK_GET_COMMON(snd_nxt);
                break;
        case offsetof(struct bpf_tcp_sock, snd_una):
                BPF_TCP_SOCK_GET_COMMON(snd_una);
                break;
        case offsetof(struct bpf_tcp_sock, mss_cache):
                BPF_TCP_SOCK_GET_COMMON(mss_cache);
                break;
        case offsetof(struct bpf_tcp_sock, ecn_flags):
                BPF_TCP_SOCK_GET_COMMON(ecn_flags);
                break;
        case offsetof(struct bpf_tcp_sock, rate_delivered):
                BPF_TCP_SOCK_GET_COMMON(rate_delivered);
                break;
        case offsetof(struct bpf_tcp_sock, rate_interval_us):
                BPF_TCP_SOCK_GET_COMMON(rate_interval_us);
                break;
        case offsetof(struct bpf_tcp_sock, packets_out):
                BPF_TCP_SOCK_GET_COMMON(packets_out);
                break;
        case offsetof(struct bpf_tcp_sock, retrans_out):
                BPF_TCP_SOCK_GET_COMMON(retrans_out);
                break;
        case offsetof(struct bpf_tcp_sock, total_retrans):
                BPF_TCP_SOCK_GET_COMMON(total_retrans);
                break;
        case offsetof(struct bpf_tcp_sock, segs_in):
                BPF_TCP_SOCK_GET_COMMON(segs_in);
                break;
        case offsetof(struct bpf_tcp_sock, data_segs_in):
                BPF_TCP_SOCK_GET_COMMON(data_segs_in);
                break;
        case offsetof(struct bpf_tcp_sock, segs_out):
                BPF_TCP_SOCK_GET_COMMON(segs_out);
                break;
        case offsetof(struct bpf_tcp_sock, data_segs_out):
                BPF_TCP_SOCK_GET_COMMON(data_segs_out);
                break;
        case offsetof(struct bpf_tcp_sock, lost_out):
                BPF_TCP_SOCK_GET_COMMON(lost_out);
                break;
        case offsetof(struct bpf_tcp_sock, sacked_out):
                BPF_TCP_SOCK_GET_COMMON(sacked_out);
                break;
        case offsetof(struct bpf_tcp_sock, bytes_received):
                BPF_TCP_SOCK_GET_COMMON(bytes_received);
                break;
        case offsetof(struct bpf_tcp_sock, bytes_acked):
                BPF_TCP_SOCK_GET_COMMON(bytes_acked);
                break;
        case offsetof(struct bpf_tcp_sock, dsack_dups):
                BPF_TCP_SOCK_GET_COMMON(dsack_dups);
                break;
        case offsetof(struct bpf_tcp_sock, delivered):
                BPF_TCP_SOCK_GET_COMMON(delivered);
                break;
        case offsetof(struct bpf_tcp_sock, delivered_ce):
                BPF_TCP_SOCK_GET_COMMON(delivered_ce);
                break;
        case offsetof(struct bpf_tcp_sock, icsk_retransmits):
                BPF_INET_SOCK_GET_COMMON(icsk_retransmits);
                break;
        }

        return insn - insn_buf;
}

BPF_CALL_1(bpf_tcp_sock, struct sock *, sk)
{
        if (sk_fullsock(sk) && sk_is_tcp(sk))
                return (unsigned long)sk;

        return (unsigned long)NULL;
}

const struct bpf_func_proto bpf_tcp_sock_proto = {
        .func           = bpf_tcp_sock,
        .gpl_only       = false,
        .ret_type       = RET_PTR_TO_TCP_SOCK_OR_NULL,
        .arg1_type      = ARG_PTR_TO_SOCK_COMMON,
};

BPF_CALL_1(bpf_get_listener_sock, struct sock *, sk)
{
        sk = sk_to_full_sk(sk);

        if (sk && sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_RCU_FREE))
                return (unsigned long)sk;

        return (unsigned long)NULL;
}

static const struct bpf_func_proto bpf_get_listener_sock_proto = {
        .func           = bpf_get_listener_sock,
        .gpl_only       = false,
        .ret_type       = RET_PTR_TO_SOCKET_OR_NULL,
        .arg1_type      = ARG_PTR_TO_SOCK_COMMON,
};

BPF_CALL_1(bpf_skb_ecn_set_ce, struct sk_buff *, skb)
{
        unsigned int iphdr_len;

        switch (skb_protocol(skb, true)) {
        case cpu_to_be16(ETH_P_IP):
                iphdr_len = sizeof(struct iphdr);
                break;
        case cpu_to_be16(ETH_P_IPV6):
                iphdr_len = sizeof(struct ipv6hdr);
                break;
        default:
                return 0;
        }

        if (skb_headlen(skb) < iphdr_len)
                return 0;

        if (skb_cloned(skb) && !skb_clone_writable(skb, iphdr_len))
                return 0;

        return INET_ECN_set_ce(skb);
}

bool bpf_xdp_sock_is_valid_access(int off, int size, enum bpf_access_type type,
                                  struct bpf_insn_access_aux *info)
{
        if (off < 0 || off >= offsetofend(struct bpf_xdp_sock, queue_id))
                return false;

        if (off % size != 0)
                return false;

        switch (off) {
        default:
                return size == sizeof(__u32);
        }
}

u32 bpf_xdp_sock_convert_ctx_access(enum bpf_access_type type,
                                    const struct bpf_insn *si,
                                    struct bpf_insn *insn_buf,
                                    struct bpf_prog *prog, u32 *target_size)
{
        struct bpf_insn *insn = insn_buf;

#define BPF_XDP_SOCK_GET(FIELD)                                         \
        do {                                                            \
                BUILD_BUG_ON(sizeof_field(struct xdp_sock, FIELD) >     \
                             sizeof_field(struct bpf_xdp_sock, FIELD)); \
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_sock, FIELD),\
                                      si->dst_reg, si->src_reg,         \
                                      offsetof(struct xdp_sock, FIELD)); \
        } while (0)

        BTF_TYPE_EMIT(struct bpf_xdp_sock);

        switch (si->off) {
        case offsetof(struct bpf_xdp_sock, queue_id):
                BPF_XDP_SOCK_GET(queue_id);
                break;
        }

        return insn - insn_buf;
}

static const struct bpf_func_proto bpf_skb_ecn_set_ce_proto = {
        .func           = bpf_skb_ecn_set_ce,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
};

BPF_CALL_5(bpf_tcp_check_syncookie, struct sock *, sk, void *, iph, u32, iph_len,
           struct tcphdr *, th, u32, th_len)
{
#ifdef CONFIG_SYN_COOKIES
        int ret;

        if (unlikely(!sk || th_len < sizeof(*th)))
                return -EINVAL;

        /* sk_listener() allows TCP_NEW_SYN_RECV, which makes no sense here. */
        if (sk->sk_protocol != IPPROTO_TCP || sk->sk_state != TCP_LISTEN)
                return -EINVAL;

        if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_syncookies))
                return -EINVAL;

        if (!th->ack || th->rst || th->syn)
                return -ENOENT;

        if (unlikely(iph_len < sizeof(struct iphdr)))
                return -EINVAL;

        if (tcp_synq_no_recent_overflow(sk))
                return -ENOENT;

        /* Both struct iphdr and struct ipv6hdr have the version field at the
         * same offset so we can cast to the shorter header (struct iphdr).
         */
        switch (((struct iphdr *)iph)->version) {
        case 4:
                if (sk->sk_family == AF_INET6 && ipv6_only_sock(sk))
                        return -EINVAL;

                ret = __cookie_v4_check((struct iphdr *)iph, th);
                break;

#if IS_ENABLED(CONFIG_IPV6)
        case 6:
                if (unlikely(iph_len < sizeof(struct ipv6hdr)))
                        return -EINVAL;

                if (sk->sk_family != AF_INET6)
                        return -EINVAL;

                ret = __cookie_v6_check((struct ipv6hdr *)iph, th);
                break;
#endif /* CONFIG_IPV6 */

        default:
                return -EPROTONOSUPPORT;
        }

        if (ret > 0)
                return 0;

        return -ENOENT;
#else
        return -ENOTSUPP;
#endif
}

static const struct bpf_func_proto bpf_tcp_check_syncookie_proto = {
        .func           = bpf_tcp_check_syncookie,
        .gpl_only       = true,
        .pkt_access     = true,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE,
        .arg4_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg5_type      = ARG_CONST_SIZE,
};

BPF_CALL_5(bpf_tcp_gen_syncookie, struct sock *, sk, void *, iph, u32, iph_len,
           struct tcphdr *, th, u32, th_len)
{
#ifdef CONFIG_SYN_COOKIES
        u32 cookie;
        u16 mss;

        if (unlikely(!sk || th_len < sizeof(*th) || th_len != th->doff * 4))
                return -EINVAL;

        if (sk->sk_protocol != IPPROTO_TCP || sk->sk_state != TCP_LISTEN)
                return -EINVAL;

        if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_syncookies))
                return -ENOENT;

        if (!th->syn || th->ack || th->fin || th->rst)
                return -EINVAL;

        if (unlikely(iph_len < sizeof(struct iphdr)))
                return -EINVAL;

        /* Both struct iphdr and struct ipv6hdr have the version field at the
         * same offset so we can cast to the shorter header (struct iphdr).
         */
        switch (((struct iphdr *)iph)->version) {
        case 4:
                if (sk->sk_family == AF_INET6 && ipv6_only_sock(sk))
                        return -EINVAL;

                mss = tcp_v4_get_syncookie(sk, iph, th, &cookie);
                break;

#if IS_ENABLED(CONFIG_IPV6)
        case 6:
                if (unlikely(iph_len < sizeof(struct ipv6hdr)))
                        return -EINVAL;

                if (sk->sk_family != AF_INET6)
                        return -EINVAL;

                mss = tcp_v6_get_syncookie(sk, iph, th, &cookie);
                break;
#endif /* CONFIG_IPV6 */

        default:
                return -EPROTONOSUPPORT;
        }
        if (mss == 0)
                return -ENOENT;

        return cookie | ((u64)mss << 32);
#else
        return -EOPNOTSUPP;
#endif /* CONFIG_SYN_COOKIES */
}

static const struct bpf_func_proto bpf_tcp_gen_syncookie_proto = {
        .func           = bpf_tcp_gen_syncookie,
        .gpl_only       = true, /* __cookie_v*_init_sequence() is GPL */
        .pkt_access     = true,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE,
        .arg4_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg5_type      = ARG_CONST_SIZE,
};

BPF_CALL_3(bpf_sk_assign, struct sk_buff *, skb, struct sock *, sk, u64, flags)
{
        if (!sk || flags != 0)
                return -EINVAL;
        if (!skb_at_tc_ingress(skb))
                return -EOPNOTSUPP;
        if (unlikely(dev_net(skb->dev) != sock_net(sk)))
                return -ENETUNREACH;
        if (sk_unhashed(sk))
                return -EOPNOTSUPP;
        if (sk_is_refcounted(sk) &&
            unlikely(!refcount_inc_not_zero(&sk->sk_refcnt)))
                return -ENOENT;

        skb_orphan(skb);
        skb->sk = sk;
        skb->destructor = sock_pfree;

        return 0;
}

static const struct bpf_func_proto bpf_sk_assign_proto = {
        .func           = bpf_sk_assign,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
        .arg3_type      = ARG_ANYTHING,
};

static const u8 *bpf_search_tcp_opt(const u8 *op, const u8 *opend,
                                    u8 search_kind, const u8 *magic,
                                    u8 magic_len, bool *eol)
{
        u8 kind, kind_len;

        *eol = false;

        while (op < opend) {
                kind = op[0];

                if (kind == TCPOPT_EOL) {
                        *eol = true;
                        return ERR_PTR(-ENOMSG);
                } else if (kind == TCPOPT_NOP) {
                        op++;
                        continue;
                }

                if (opend - op < 2 || opend - op < op[1] || op[1] < 2)
                        /* Something is wrong in the received header.
                         * Follow the TCP stack's tcp_parse_options()
                         * and just bail here.
                         */
                        return ERR_PTR(-EFAULT);

                kind_len = op[1];
                if (search_kind == kind) {
                        if (!magic_len)
                                return op;

                        if (magic_len > kind_len - 2)
                                return ERR_PTR(-ENOMSG);

                        if (!memcmp(&op[2], magic, magic_len))
                                return op;
                }

                op += kind_len;
        }

        return ERR_PTR(-ENOMSG);
}

BPF_CALL_4(bpf_sock_ops_load_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
           void *, search_res, u32, len, u64, flags)
{
        bool eol, load_syn = flags & BPF_LOAD_HDR_OPT_TCP_SYN;
        const u8 *op, *opend, *magic, *search = search_res;
        u8 search_kind, search_len, copy_len, magic_len;
        int ret;

        if (!is_locked_tcp_sock_ops(bpf_sock))
                return -EOPNOTSUPP;

        /* 2 byte is the minimal option len except TCPOPT_NOP and
         * TCPOPT_EOL which are useless for the bpf prog to learn
         * and this helper disallow loading them also.
         */
        if (len < 2 || flags & ~BPF_LOAD_HDR_OPT_TCP_SYN)
                return -EINVAL;

        search_kind = search[0];
        search_len = search[1];

        if (search_len > len || search_kind == TCPOPT_NOP ||
            search_kind == TCPOPT_EOL)
                return -EINVAL;

        if (search_kind == TCPOPT_EXP || search_kind == 253) {
                /* 16 or 32 bit magic.  +2 for kind and kind length */
                if (search_len != 4 && search_len != 6)
                        return -EINVAL;
                magic = &search[2];
                magic_len = search_len - 2;
        } else {
                if (search_len)
                        return -EINVAL;
                magic = NULL;
                magic_len = 0;
        }

        if (load_syn) {
                ret = bpf_sock_ops_get_syn(bpf_sock, TCP_BPF_SYN, &op);
                if (ret < 0)
                        return ret;

                opend = op + ret;
                op += sizeof(struct tcphdr);
        } else {
                if (!bpf_sock->skb ||
                    bpf_sock->op == BPF_SOCK_OPS_HDR_OPT_LEN_CB)
                        /* This bpf_sock->op cannot call this helper */
                        return -EPERM;

                opend = bpf_sock->skb_data_end;
                op = bpf_sock->skb->data + sizeof(struct tcphdr);
        }

        op = bpf_search_tcp_opt(op, opend, search_kind, magic, magic_len,
                                &eol);
        if (IS_ERR(op))
                return PTR_ERR(op);

        copy_len = op[1];
        ret = copy_len;
        if (copy_len > len) {
                ret = -ENOSPC;
                copy_len = len;
        }

        memcpy(search_res, op, copy_len);
        return ret;
}

static const struct bpf_func_proto bpf_sock_ops_load_hdr_opt_proto = {
        .func           = bpf_sock_ops_load_hdr_opt,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_WRITE,
        .arg3_type      = ARG_CONST_SIZE,
        .arg4_type      = ARG_ANYTHING,
};

BPF_CALL_4(bpf_sock_ops_store_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
           const void *, from, u32, len, u64, flags)
{
        u8 new_kind, new_kind_len, magic_len = 0, *opend;
        const u8 *op, *new_op, *magic = NULL;
        struct sk_buff *skb;
        bool eol;

        if (bpf_sock->op != BPF_SOCK_OPS_WRITE_HDR_OPT_CB)
                return -EPERM;

        if (len < 2 || flags)
                return -EINVAL;

        new_op = from;
        new_kind = new_op[0];
        new_kind_len = new_op[1];

        if (new_kind_len > len || new_kind == TCPOPT_NOP ||
            new_kind == TCPOPT_EOL)
                return -EINVAL;

        if (new_kind_len > bpf_sock->remaining_opt_len)
                return -ENOSPC;

        /* 253 is another experimental kind */
        if (new_kind == TCPOPT_EXP || new_kind == 253)  {
                if (new_kind_len < 4)
                        return -EINVAL;
                /* Match for the 2 byte magic also.
                 * RFC 6994: the magic could be 2 or 4 bytes.
                 * Hence, matching by 2 byte only is on the
                 * conservative side but it is the right
                 * thing to do for the 'search-for-duplication'
                 * purpose.
                 */
                magic = &new_op[2];
                magic_len = 2;
        }

        /* Check for duplication */
        skb = bpf_sock->skb;
        op = skb->data + sizeof(struct tcphdr);
        opend = bpf_sock->skb_data_end;

        op = bpf_search_tcp_opt(op, opend, new_kind, magic, magic_len,
                                &eol);
        if (!IS_ERR(op))
                return -EEXIST;

        if (PTR_ERR(op) != -ENOMSG)
                return PTR_ERR(op);

        if (eol)
                /* The option has been ended.  Treat it as no more
                 * header option can be written.
                 */
                return -ENOSPC;

        /* No duplication found.  Store the header option. */
        memcpy(opend, from, new_kind_len);

        bpf_sock->remaining_opt_len -= new_kind_len;
        bpf_sock->skb_data_end += new_kind_len;

        return 0;
}

static const struct bpf_func_proto bpf_sock_ops_store_hdr_opt_proto = {
        .func           = bpf_sock_ops_store_hdr_opt,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE,
        .arg4_type      = ARG_ANYTHING,
};

BPF_CALL_3(bpf_sock_ops_reserve_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
           u32, len, u64, flags)
{
        if (bpf_sock->op != BPF_SOCK_OPS_HDR_OPT_LEN_CB)
                return -EPERM;

        if (flags || len < 2)
                return -EINVAL;

        if (len > bpf_sock->remaining_opt_len)
                return -ENOSPC;

        bpf_sock->remaining_opt_len -= len;

        return 0;
}

static const struct bpf_func_proto bpf_sock_ops_reserve_hdr_opt_proto = {
        .func           = bpf_sock_ops_reserve_hdr_opt,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
};

BPF_CALL_3(bpf_skb_set_tstamp, struct sk_buff *, skb,
           u64, tstamp, u32, tstamp_type)
{
        /* skb_clear_delivery_time() is done for inet protocol */
        if (skb->protocol != htons(ETH_P_IP) &&
            skb->protocol != htons(ETH_P_IPV6))
                return -EOPNOTSUPP;

        switch (tstamp_type) {
        case BPF_SKB_CLOCK_REALTIME:
                skb->tstamp = tstamp;
                skb->tstamp_type = SKB_CLOCK_REALTIME;
                break;
        case BPF_SKB_CLOCK_MONOTONIC:
                if (!tstamp)
                        return -EINVAL;
                skb->tstamp = tstamp;
                skb->tstamp_type = SKB_CLOCK_MONOTONIC;
                break;
        case BPF_SKB_CLOCK_TAI:
                if (!tstamp)
                        return -EINVAL;
                skb->tstamp = tstamp;
                skb->tstamp_type = SKB_CLOCK_TAI;
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static const struct bpf_func_proto bpf_skb_set_tstamp_proto = {
        .func           = bpf_skb_set_tstamp,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_ANYTHING,
};

#ifdef CONFIG_SYN_COOKIES
BPF_CALL_3(bpf_tcp_raw_gen_syncookie_ipv4, struct iphdr *, iph,
           struct tcphdr *, th, u32, th_len)
{
        u32 cookie;
        u16 mss;

        if (unlikely(th_len < sizeof(*th) || th_len != th->doff * 4))
                return -EINVAL;

        mss = tcp_parse_mss_option(th, 0) ?: TCP_MSS_DEFAULT;
        cookie = __cookie_v4_init_sequence(iph, th, &mss);

        return cookie | ((u64)mss << 32);
}

static const struct bpf_func_proto bpf_tcp_raw_gen_syncookie_ipv4_proto = {
        .func           = bpf_tcp_raw_gen_syncookie_ipv4,
        .gpl_only       = true, /* __cookie_v4_init_sequence() is GPL */
        .pkt_access     = true,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_RDONLY,
        .arg1_size      = sizeof(struct iphdr),
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
};

BPF_CALL_3(bpf_tcp_raw_gen_syncookie_ipv6, struct ipv6hdr *, iph,
           struct tcphdr *, th, u32, th_len)
{
#if IS_ENABLED(CONFIG_IPV6)
        const u16 mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) -
                sizeof(struct ipv6hdr);
        u32 cookie;
        u16 mss;

        if (unlikely(th_len < sizeof(*th) || th_len != th->doff * 4))
                return -EINVAL;

        mss = tcp_parse_mss_option(th, 0) ?: mss_clamp;
        cookie = __cookie_v6_init_sequence(iph, th, &mss);

        return cookie | ((u64)mss << 32);
#else
        return -EPROTONOSUPPORT;
#endif
}

static const struct bpf_func_proto bpf_tcp_raw_gen_syncookie_ipv6_proto = {
        .func           = bpf_tcp_raw_gen_syncookie_ipv6,
        .gpl_only       = true, /* __cookie_v6_init_sequence() is GPL */
        .pkt_access     = true,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_RDONLY,
        .arg1_size      = sizeof(struct ipv6hdr),
        .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
        .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
};

BPF_CALL_2(bpf_tcp_raw_check_syncookie_ipv4, struct iphdr *, iph,
           struct tcphdr *, th)
{
        if (__cookie_v4_check(iph, th) > 0)
                return 0;

        return -EACCES;
}

static const struct bpf_func_proto bpf_tcp_raw_check_syncookie_ipv4_proto = {
        .func           = bpf_tcp_raw_check_syncookie_ipv4,
        .gpl_only       = true, /* __cookie_v4_check is GPL */
        .pkt_access     = true,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_RDONLY,
        .arg1_size      = sizeof(struct iphdr),
        .arg2_type      = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_RDONLY,
        .arg2_size      = sizeof(struct tcphdr),
};

BPF_CALL_2(bpf_tcp_raw_check_syncookie_ipv6, struct ipv6hdr *, iph,
           struct tcphdr *, th)
{
#if IS_ENABLED(CONFIG_IPV6)
        if (__cookie_v6_check(iph, th) > 0)
                return 0;

        return -EACCES;
#else
        return -EPROTONOSUPPORT;
#endif
}

static const struct bpf_func_proto bpf_tcp_raw_check_syncookie_ipv6_proto = {
        .func           = bpf_tcp_raw_check_syncookie_ipv6,
        .gpl_only       = true, /* __cookie_v6_check is GPL */
        .pkt_access     = true,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_RDONLY,
        .arg1_size      = sizeof(struct ipv6hdr),
        .arg2_type      = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_RDONLY,
        .arg2_size      = sizeof(struct tcphdr),
};
#endif /* CONFIG_SYN_COOKIES */

#endif /* CONFIG_INET */

bool bpf_helper_changes_pkt_data(enum bpf_func_id func_id)
{
        switch (func_id) {
        case BPF_FUNC_clone_redirect:
        case BPF_FUNC_l3_csum_replace:
        case BPF_FUNC_l4_csum_replace:
        case BPF_FUNC_lwt_push_encap:
        case BPF_FUNC_lwt_seg6_action:
        case BPF_FUNC_lwt_seg6_adjust_srh:
        case BPF_FUNC_lwt_seg6_store_bytes:
        case BPF_FUNC_msg_pop_data:
        case BPF_FUNC_msg_pull_data:
        case BPF_FUNC_msg_push_data:
        case BPF_FUNC_skb_adjust_room:
        case BPF_FUNC_skb_change_head:
        case BPF_FUNC_skb_change_proto:
        case BPF_FUNC_skb_change_tail:
        case BPF_FUNC_skb_pull_data:
        case BPF_FUNC_skb_store_bytes:
        case BPF_FUNC_skb_vlan_pop:
        case BPF_FUNC_skb_vlan_push:
        case BPF_FUNC_store_hdr_opt:
        case BPF_FUNC_xdp_adjust_head:
        case BPF_FUNC_xdp_adjust_meta:
        case BPF_FUNC_xdp_adjust_tail:
        /* tail-called program could call any of the above */
        case BPF_FUNC_tail_call:
                return true;
        default:
                return false;
        }
}

const struct bpf_func_proto bpf_event_output_data_proto __weak;
const struct bpf_func_proto bpf_sk_storage_get_cg_sock_proto __weak;

static const struct bpf_func_proto *
sock_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
        const struct bpf_func_proto *func_proto;

        func_proto = cgroup_common_func_proto(func_id, prog);
        if (func_proto)
                return func_proto;

        switch (func_id) {
        case BPF_FUNC_get_socket_cookie:
                return &bpf_get_socket_cookie_sock_proto;
        case BPF_FUNC_get_netns_cookie:
                return &bpf_get_netns_cookie_sock_proto;
        case BPF_FUNC_perf_event_output:
                return &bpf_event_output_data_proto;
        case BPF_FUNC_sk_storage_get:
                return &bpf_sk_storage_get_cg_sock_proto;
        case BPF_FUNC_ktime_get_coarse_ns:
                return &bpf_ktime_get_coarse_ns_proto;
        case BPF_FUNC_setsockopt:
                switch (prog->expected_attach_type) {
                case BPF_CGROUP_INET_SOCK_CREATE:
                        return &bpf_sock_create_setsockopt_proto;
                default:
                        return NULL;
                }
        case BPF_FUNC_getsockopt:
                switch (prog->expected_attach_type) {
                case BPF_CGROUP_INET_SOCK_CREATE:
                        return &bpf_sock_create_getsockopt_proto;
                default:
                        return NULL;
                }
        default:
                return bpf_base_func_proto(func_id, prog);
        }
}

static const struct bpf_func_proto *
sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
        const struct bpf_func_proto *func_proto;

        func_proto = cgroup_common_func_proto(func_id, prog);
        if (func_proto)
                return func_proto;

        switch (func_id) {
        case BPF_FUNC_bind:
                switch (prog->expected_attach_type) {
                case BPF_CGROUP_INET4_CONNECT:
                case BPF_CGROUP_INET6_CONNECT:
                        return &bpf_bind_proto;
                default:
                        return NULL;
                }
        case BPF_FUNC_get_socket_cookie:
                return &bpf_get_socket_cookie_sock_addr_proto;
        case BPF_FUNC_get_netns_cookie:
                return &bpf_get_netns_cookie_sock_addr_proto;
        case BPF_FUNC_perf_event_output:
                return &bpf_event_output_data_proto;
#ifdef CONFIG_INET
        case BPF_FUNC_sk_lookup_tcp:
                return &bpf_sock_addr_sk_lookup_tcp_proto;
        case BPF_FUNC_sk_lookup_udp:
                return &bpf_sock_addr_sk_lookup_udp_proto;
        case BPF_FUNC_sk_release:
                return &bpf_sk_release_proto;
        case BPF_FUNC_skc_lookup_tcp:
                return &bpf_sock_addr_skc_lookup_tcp_proto;
#endif /* CONFIG_INET */
        case BPF_FUNC_sk_storage_get:
                return &bpf_sk_storage_get_proto;
        case BPF_FUNC_sk_storage_delete:
                return &bpf_sk_storage_delete_proto;
        case BPF_FUNC_setsockopt:
                switch (prog->expected_attach_type) {
                case BPF_CGROUP_INET4_BIND:
                case BPF_CGROUP_INET6_BIND:
                case BPF_CGROUP_INET4_CONNECT:
                case BPF_CGROUP_INET6_CONNECT:
                case BPF_CGROUP_UNIX_CONNECT:
                case BPF_CGROUP_UDP4_RECVMSG:
                case BPF_CGROUP_UDP6_RECVMSG:
                case BPF_CGROUP_UNIX_RECVMSG:
                case BPF_CGROUP_UDP4_SENDMSG:
                case BPF_CGROUP_UDP6_SENDMSG:
                case BPF_CGROUP_UNIX_SENDMSG:
                case BPF_CGROUP_INET4_GETPEERNAME:
                case BPF_CGROUP_INET6_GETPEERNAME:
                case BPF_CGROUP_UNIX_GETPEERNAME:
                case BPF_CGROUP_INET4_GETSOCKNAME:
                case BPF_CGROUP_INET6_GETSOCKNAME:
                case BPF_CGROUP_UNIX_GETSOCKNAME:
                        return &bpf_sock_addr_setsockopt_proto;
                default:
                        return NULL;
                }
        case BPF_FUNC_getsockopt:
                switch (prog->expected_attach_type) {
                case BPF_CGROUP_INET4_BIND:
                case BPF_CGROUP_INET6_BIND:
                case BPF_CGROUP_INET4_CONNECT:
                case BPF_CGROUP_INET6_CONNECT:
                case BPF_CGROUP_UNIX_CONNECT:
                case BPF_CGROUP_UDP4_RECVMSG:
                case BPF_CGROUP_UDP6_RECVMSG:
                case BPF_CGROUP_UNIX_RECVMSG:
                case BPF_CGROUP_UDP4_SENDMSG:
                case BPF_CGROUP_UDP6_SENDMSG:
                case BPF_CGROUP_UNIX_SENDMSG:
                case BPF_CGROUP_INET4_GETPEERNAME:
                case BPF_CGROUP_INET6_GETPEERNAME:
                case BPF_CGROUP_UNIX_GETPEERNAME:
                case BPF_CGROUP_INET4_GETSOCKNAME:
                case BPF_CGROUP_INET6_GETSOCKNAME:
                case BPF_CGROUP_UNIX_GETSOCKNAME:
                        return &bpf_sock_addr_getsockopt_proto;
                default:
                        return NULL;
                }
        default:
                return bpf_sk_base_func_proto(func_id, prog);
        }
}

static const struct bpf_func_proto *
sk_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
        switch (func_id) {
        case BPF_FUNC_skb_load_bytes:
                return &bpf_skb_load_bytes_proto;
        case BPF_FUNC_skb_load_bytes_relative:
                return &bpf_skb_load_bytes_relative_proto;
        case BPF_FUNC_get_socket_cookie:
                return &bpf_get_socket_cookie_proto;
        case BPF_FUNC_get_netns_cookie:
                return &bpf_get_netns_cookie_proto;
        case BPF_FUNC_get_socket_uid:
                return &bpf_get_socket_uid_proto;
        case BPF_FUNC_perf_event_output:
                return &bpf_skb_event_output_proto;
        default:
                return bpf_sk_base_func_proto(func_id, prog);
        }
}

const struct bpf_func_proto bpf_sk_storage_get_proto __weak;
const struct bpf_func_proto bpf_sk_storage_delete_proto __weak;

static const struct bpf_func_proto *
cg_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
        const struct bpf_func_proto *func_proto;

        func_proto = cgroup_common_func_proto(func_id, prog);
        if (func_proto)
                return func_proto;

        switch (func_id) {
        case BPF_FUNC_sk_fullsock:
                return &bpf_sk_fullsock_proto;
        case BPF_FUNC_sk_storage_get:
                return &bpf_sk_storage_get_proto;
        case BPF_FUNC_sk_storage_delete:
                return &bpf_sk_storage_delete_proto;
        case BPF_FUNC_perf_event_output:
                return &bpf_skb_event_output_proto;
#ifdef CONFIG_SOCK_CGROUP_DATA
        case BPF_FUNC_skb_cgroup_id:
                return &bpf_skb_cgroup_id_proto;
        case BPF_FUNC_skb_ancestor_cgroup_id:
                return &bpf_skb_ancestor_cgroup_id_proto;
        case BPF_FUNC_sk_cgroup_id:
                return &bpf_sk_cgroup_id_proto;
        case BPF_FUNC_sk_ancestor_cgroup_id:
                return &bpf_sk_ancestor_cgroup_id_proto;
#endif
#ifdef CONFIG_INET
        case BPF_FUNC_sk_lookup_tcp:
                return &bpf_sk_lookup_tcp_proto;
        case BPF_FUNC_sk_lookup_udp:
                return &bpf_sk_lookup_udp_proto;
        case BPF_FUNC_sk_release:
                return &bpf_sk_release_proto;
        case BPF_FUNC_skc_lookup_tcp:
                return &bpf_skc_lookup_tcp_proto;
        case BPF_FUNC_tcp_sock:
                return &bpf_tcp_sock_proto;
        case BPF_FUNC_get_listener_sock:
                return &bpf_get_listener_sock_proto;
        case BPF_FUNC_skb_ecn_set_ce:
                return &bpf_skb_ecn_set_ce_proto;
#endif
        default:
                return sk_filter_func_proto(func_id, prog);
        }
}

static const struct bpf_func_proto *
tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
        switch (func_id) {
        case BPF_FUNC_skb_store_bytes:
                return &bpf_skb_store_bytes_proto;
        case BPF_FUNC_skb_load_bytes:
                return &bpf_skb_load_bytes_proto;
        case BPF_FUNC_skb_load_bytes_relative:
                return &bpf_skb_load_bytes_relative_proto;
        case BPF_FUNC_skb_pull_data:
                return &bpf_skb_pull_data_proto;
        case BPF_FUNC_csum_diff:
                return &bpf_csum_diff_proto;
        case BPF_FUNC_csum_update:
                return &bpf_csum_update_proto;
        case BPF_FUNC_csum_level:
                return &bpf_csum_level_proto;
        case BPF_FUNC_l3_csum_replace:
                return &bpf_l3_csum_replace_proto;
        case BPF_FUNC_l4_csum_replace:
                return &bpf_l4_csum_replace_proto;
        case BPF_FUNC_clone_redirect:
                return &bpf_clone_redirect_proto;
        case BPF_FUNC_get_cgroup_classid:
                return &bpf_get_cgroup_classid_proto;
        case BPF_FUNC_skb_vlan_push:
                return &bpf_skb_vlan_push_proto;
        case BPF_FUNC_skb_vlan_pop:
                return &bpf_skb_vlan_pop_proto;
        case BPF_FUNC_skb_change_proto:
                return &bpf_skb_change_proto_proto;
        case BPF_FUNC_skb_change_type:
                return &bpf_skb_change_type_proto;
        case BPF_FUNC_skb_adjust_room:
                return &bpf_skb_adjust_room_proto;
        case BPF_FUNC_skb_change_tail:
                return &bpf_skb_change_tail_proto;
        case BPF_FUNC_skb_change_head:
                return &bpf_skb_change_head_proto;
        case BPF_FUNC_skb_get_tunnel_key:
                return &bpf_skb_get_tunnel_key_proto;
        case BPF_FUNC_skb_set_tunnel_key:
                return bpf_get_skb_set_tunnel_proto(func_id);
        case BPF_FUNC_skb_get_tunnel_opt:
                return &bpf_skb_get_tunnel_opt_proto;
        case BPF_FUNC_skb_set_tunnel_opt:
                return bpf_get_skb_set_tunnel_proto(func_id);
        case BPF_FUNC_redirect:
                return &bpf_redirect_proto;
        case BPF_FUNC_redirect_neigh:
                return &bpf_redirect_neigh_proto;
        case BPF_FUNC_redirect_peer:
                return &bpf_redirect_peer_proto;
        case BPF_FUNC_get_route_realm:
                return &bpf_get_route_realm_proto;
        case BPF_FUNC_get_hash_recalc:
                return &bpf_get_hash_recalc_proto;
        case BPF_FUNC_set_hash_invalid:
                return &bpf_set_hash_invalid_proto;
        case BPF_FUNC_set_hash:
                return &bpf_set_hash_proto;
        case BPF_FUNC_perf_event_output:
                return &bpf_skb_event_output_proto;
        case BPF_FUNC_get_smp_processor_id:
                return &bpf_get_smp_processor_id_proto;
        case BPF_FUNC_skb_under_cgroup:
                return &bpf_skb_under_cgroup_proto;
        case BPF_FUNC_get_socket_cookie:
                return &bpf_get_socket_cookie_proto;
        case BPF_FUNC_get_netns_cookie:
                return &bpf_get_netns_cookie_proto;
        case BPF_FUNC_get_socket_uid:
                return &bpf_get_socket_uid_proto;
        case BPF_FUNC_fib_lookup:
                return &bpf_skb_fib_lookup_proto;
        case BPF_FUNC_check_mtu:
                return &bpf_skb_check_mtu_proto;
        case BPF_FUNC_sk_fullsock:
                return &bpf_sk_fullsock_proto;
        case BPF_FUNC_sk_storage_get:
                return &bpf_sk_storage_get_proto;
        case BPF_FUNC_sk_storage_delete:
                return &bpf_sk_storage_delete_proto;
#ifdef CONFIG_XFRM
        case BPF_FUNC_skb_get_xfrm_state:
                return &bpf_skb_get_xfrm_state_proto;
#endif
#ifdef CONFIG_CGROUP_NET_CLASSID
        case BPF_FUNC_skb_cgroup_classid:
                return &bpf_skb_cgroup_classid_proto;
#endif
#ifdef CONFIG_SOCK_CGROUP_DATA
        case BPF_FUNC_skb_cgroup_id:
                return &bpf_skb_cgroup_id_proto;
        case BPF_FUNC_skb_ancestor_cgroup_id:
                return &bpf_skb_ancestor_cgroup_id_proto;
#endif
#ifdef CONFIG_INET
        case BPF_FUNC_sk_lookup_tcp:
                return &bpf_tc_sk_lookup_tcp_proto;
        case BPF_FUNC_sk_lookup_udp:
                return &bpf_tc_sk_lookup_udp_proto;
        case BPF_FUNC_sk_release:
                return &bpf_sk_release_proto;
        case BPF_FUNC_tcp_sock:
                return &bpf_tcp_sock_proto;
        case BPF_FUNC_get_listener_sock:
                return &bpf_get_listener_sock_proto;
        case BPF_FUNC_skc_lookup_tcp:
                return &bpf_tc_skc_lookup_tcp_proto;
        case BPF_FUNC_tcp_check_syncookie:
                return &bpf_tcp_check_syncookie_proto;
        case BPF_FUNC_skb_ecn_set_ce:
                return &bpf_skb_ecn_set_ce_proto;
        case BPF_FUNC_tcp_gen_syncookie:
                return &bpf_tcp_gen_syncookie_proto;
        case BPF_FUNC_sk_assign:
                return &bpf_sk_assign_proto;
        case BPF_FUNC_skb_set_tstamp:
                return &bpf_skb_set_tstamp_proto;
#ifdef CONFIG_SYN_COOKIES
        case BPF_FUNC_tcp_raw_gen_syncookie_ipv4:
                return &bpf_tcp_raw_gen_syncookie_ipv4_proto;
        case BPF_FUNC_tcp_raw_gen_syncookie_ipv6:
                return &bpf_tcp_raw_gen_syncookie_ipv6_proto;
        case BPF_FUNC_tcp_raw_check_syncookie_ipv4:
                return &bpf_tcp_raw_check_syncookie_ipv4_proto;
        case BPF_FUNC_tcp_raw_check_syncookie_ipv6:
                return &bpf_tcp_raw_check_syncookie_ipv6_proto;
#endif
#endif
        default:
                return bpf_sk_base_func_proto(func_id, prog);
        }
}

static const struct bpf_func_proto *
xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
        switch (func_id) {
        case BPF_FUNC_perf_event_output:
                return &bpf_xdp_event_output_proto;
        case BPF_FUNC_get_smp_processor_id:
                return &bpf_get_smp_processor_id_proto;
        case BPF_FUNC_csum_diff:
                return &bpf_csum_diff_proto;
        case BPF_FUNC_xdp_adjust_head:
                return &bpf_xdp_adjust_head_proto;
        case BPF_FUNC_xdp_adjust_meta:
                return &bpf_xdp_adjust_meta_proto;
        case BPF_FUNC_redirect:
                return &bpf_xdp_redirect_proto;
        case BPF_FUNC_redirect_map:
                return &bpf_xdp_redirect_map_proto;
        case BPF_FUNC_xdp_adjust_tail:
                return &bpf_xdp_adjust_tail_proto;
        case BPF_FUNC_xdp_get_buff_len:
                return &bpf_xdp_get_buff_len_proto;
        case BPF_FUNC_xdp_load_bytes:
                return &bpf_xdp_load_bytes_proto;
        case BPF_FUNC_xdp_store_bytes:
                return &bpf_xdp_store_bytes_proto;
        case BPF_FUNC_fib_lookup:
                return &bpf_xdp_fib_lookup_proto;
        case BPF_FUNC_check_mtu:
                return &bpf_xdp_check_mtu_proto;
#ifdef CONFIG_INET
        case BPF_FUNC_sk_lookup_udp:
                return &bpf_xdp_sk_lookup_udp_proto;
        case BPF_FUNC_sk_lookup_tcp:
                return &bpf_xdp_sk_lookup_tcp_proto;
        case BPF_FUNC_sk_release:
                return &bpf_sk_release_proto;
        case BPF_FUNC_skc_lookup_tcp:
                return &bpf_xdp_skc_lookup_tcp_proto;
        case BPF_FUNC_tcp_check_syncookie:
                return &bpf_tcp_check_syncookie_proto;
        case BPF_FUNC_tcp_gen_syncookie:
                return &bpf_tcp_gen_syncookie_proto;
#ifdef CONFIG_SYN_COOKIES
        case BPF_FUNC_tcp_raw_gen_syncookie_ipv4:
                return &bpf_tcp_raw_gen_syncookie_ipv4_proto;
        case BPF_FUNC_tcp_raw_gen_syncookie_ipv6:
                return &bpf_tcp_raw_gen_syncookie_ipv6_proto;
        case BPF_FUNC_tcp_raw_check_syncookie_ipv4:
                return &bpf_tcp_raw_check_syncookie_ipv4_proto;
        case BPF_FUNC_tcp_raw_check_syncookie_ipv6:
                return &bpf_tcp_raw_check_syncookie_ipv6_proto;
#endif
#endif
        default:
                return bpf_sk_base_func_proto(func_id, prog);
        }

#if IS_MODULE(CONFIG_NF_CONNTRACK) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES)
        /* The nf_conn___init type is used in the NF_CONNTRACK kfuncs. The
         * kfuncs are defined in two different modules, and we want to be able
         * to use them interchangeably with the same BTF type ID. Because modules
         * can't de-duplicate BTF IDs between each other, we need the type to be
         * referenced in the vmlinux BTF or the verifier will get confused about
         * the different types. So we add this dummy type reference which will
         * be included in vmlinux BTF, allowing both modules to refer to the
         * same type ID.
         */
        BTF_TYPE_EMIT(struct nf_conn___init);
#endif
}

const struct bpf_func_proto bpf_sock_map_update_proto __weak;
const struct bpf_func_proto bpf_sock_hash_update_proto __weak;

static const struct bpf_func_proto *
sock_ops_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
        const struct bpf_func_proto *func_proto;

        func_proto = cgroup_common_func_proto(func_id, prog);
        if (func_proto)
                return func_proto;

        switch (func_id) {
        case BPF_FUNC_setsockopt:
                return &bpf_sock_ops_setsockopt_proto;
        case BPF_FUNC_getsockopt:
                return &bpf_sock_ops_getsockopt_proto;
        case BPF_FUNC_sock_ops_cb_flags_set:
                return &bpf_sock_ops_cb_flags_set_proto;
        case BPF_FUNC_sock_map_update:
                return &bpf_sock_map_update_proto;
        case BPF_FUNC_sock_hash_update:
                return &bpf_sock_hash_update_proto;
        case BPF_FUNC_get_socket_cookie:
                return &bpf_get_socket_cookie_sock_ops_proto;
        case BPF_FUNC_perf_event_output:
                return &bpf_event_output_data_proto;
        case BPF_FUNC_sk_storage_get:
                return &bpf_sk_storage_get_proto;
        case BPF_FUNC_sk_storage_delete:
                return &bpf_sk_storage_delete_proto;
        case BPF_FUNC_get_netns_cookie:
                return &bpf_get_netns_cookie_sock_ops_proto;
#ifdef CONFIG_INET
        case BPF_FUNC_load_hdr_opt:
                return &bpf_sock_ops_load_hdr_opt_proto;
        case BPF_FUNC_store_hdr_opt:
                return &bpf_sock_ops_store_hdr_opt_proto;
        case BPF_FUNC_reserve_hdr_opt:
                return &bpf_sock_ops_reserve_hdr_opt_proto;
        case BPF_FUNC_tcp_sock:
                return &bpf_tcp_sock_proto;
#endif /* CONFIG_INET */
        default:
                return bpf_sk_base_func_proto(func_id, prog);
        }
}

const struct bpf_func_proto bpf_msg_redirect_map_proto __weak;
const struct bpf_func_proto bpf_msg_redirect_hash_proto __weak;

static const struct bpf_func_proto *
sk_msg_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
        switch (func_id) {
        case BPF_FUNC_msg_redirect_map:
                return &bpf_msg_redirect_map_proto;
        case BPF_FUNC_msg_redirect_hash:
                return &bpf_msg_redirect_hash_proto;
        case BPF_FUNC_msg_apply_bytes:
                return &bpf_msg_apply_bytes_proto;
        case BPF_FUNC_msg_cork_bytes:
                return &bpf_msg_cork_bytes_proto;
        case BPF_FUNC_msg_pull_data:
                return &bpf_msg_pull_data_proto;
        case BPF_FUNC_msg_push_data:
                return &bpf_msg_push_data_proto;
        case BPF_FUNC_msg_pop_data:
                return &bpf_msg_pop_data_proto;
        case BPF_FUNC_perf_event_output:
                return &bpf_event_output_data_proto;
        case BPF_FUNC_sk_storage_get:
                return &bpf_sk_storage_get_proto;
        case BPF_FUNC_sk_storage_delete:
                return &bpf_sk_storage_delete_proto;
        case BPF_FUNC_get_netns_cookie:
                return &bpf_get_netns_cookie_sk_msg_proto;
        default:
                return bpf_sk_base_func_proto(func_id, prog);
        }
}

const struct bpf_func_proto bpf_sk_redirect_map_proto __weak;
const struct bpf_func_proto bpf_sk_redirect_hash_proto __weak;

static const struct bpf_func_proto *
sk_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
        switch (func_id) {
        case BPF_FUNC_skb_store_bytes:
                return &bpf_skb_store_bytes_proto;
        case BPF_FUNC_skb_load_bytes:
                return &bpf_skb_load_bytes_proto;
        case BPF_FUNC_skb_pull_data:
                return &sk_skb_pull_data_proto;
        case BPF_FUNC_skb_change_tail:
                return &sk_skb_change_tail_proto;
        case BPF_FUNC_skb_change_head:
                return &sk_skb_change_head_proto;
        case BPF_FUNC_skb_adjust_room:
                return &sk_skb_adjust_room_proto;
        case BPF_FUNC_get_socket_cookie:
                return &bpf_get_socket_cookie_proto;
        case BPF_FUNC_get_socket_uid:
                return &bpf_get_socket_uid_proto;
        case BPF_FUNC_sk_redirect_map:
                return &bpf_sk_redirect_map_proto;
        case BPF_FUNC_sk_redirect_hash:
                return &bpf_sk_redirect_hash_proto;
        case BPF_FUNC_perf_event_output:
                return &bpf_skb_event_output_proto;
#ifdef CONFIG_INET
        case BPF_FUNC_sk_lookup_tcp:
                return &bpf_sk_lookup_tcp_proto;
        case BPF_FUNC_sk_lookup_udp:
                return &bpf_sk_lookup_udp_proto;
        case BPF_FUNC_sk_release:
                return &bpf_sk_release_proto;
        case BPF_FUNC_skc_lookup_tcp:
                return &bpf_skc_lookup_tcp_proto;
#endif
        default:
                return bpf_sk_base_func_proto(func_id, prog);
        }
}

static const struct bpf_func_proto *
flow_dissector_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
        switch (func_id) {
        case BPF_FUNC_skb_load_bytes:
                return &bpf_flow_dissector_load_bytes_proto;
        default:
                return bpf_sk_base_func_proto(func_id, prog);
        }
}

static const struct bpf_func_proto *
lwt_out_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
        switch (func_id) {
        case BPF_FUNC_skb_load_bytes:
                return &bpf_skb_load_bytes_proto;
        case BPF_FUNC_skb_pull_data:
                return &bpf_skb_pull_data_proto;
        case BPF_FUNC_csum_diff:
                return &bpf_csum_diff_proto;
        case BPF_FUNC_get_cgroup_classid:
                return &bpf_get_cgroup_classid_proto;
        case BPF_FUNC_get_route_realm:
                return &bpf_get_route_realm_proto;
        case BPF_FUNC_get_hash_recalc:
                return &bpf_get_hash_recalc_proto;
        case BPF_FUNC_perf_event_output:
                return &bpf_skb_event_output_proto;
        case BPF_FUNC_get_smp_processor_id:
                return &bpf_get_smp_processor_id_proto;
        case BPF_FUNC_skb_under_cgroup:
                return &bpf_skb_under_cgroup_proto;
        default:
                return bpf_sk_base_func_proto(func_id, prog);
        }
}

static const struct bpf_func_proto *
lwt_in_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
        switch (func_id) {
        case BPF_FUNC_lwt_push_encap:
                return &bpf_lwt_in_push_encap_proto;
        default:
                return lwt_out_func_proto(func_id, prog);
        }
}

static const struct bpf_func_proto *
lwt_xmit_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
        switch (func_id) {
        case BPF_FUNC_skb_get_tunnel_key:
                return &bpf_skb_get_tunnel_key_proto;
        case BPF_FUNC_skb_set_tunnel_key:
                return bpf_get_skb_set_tunnel_proto(func_id);
        case BPF_FUNC_skb_get_tunnel_opt:
                return &bpf_skb_get_tunnel_opt_proto;
        case BPF_FUNC_skb_set_tunnel_opt:
                return bpf_get_skb_set_tunnel_proto(func_id);
        case BPF_FUNC_redirect:
                return &bpf_redirect_proto;
        case BPF_FUNC_clone_redirect:
                return &bpf_clone_redirect_proto;
        case BPF_FUNC_skb_change_tail:
                return &bpf_skb_change_tail_proto;
        case BPF_FUNC_skb_change_head:
                return &bpf_skb_change_head_proto;
        case BPF_FUNC_skb_store_bytes:
                return &bpf_skb_store_bytes_proto;
        case BPF_FUNC_csum_update:
                return &bpf_csum_update_proto;
        case BPF_FUNC_csum_level:
                return &bpf_csum_level_proto;
        case BPF_FUNC_l3_csum_replace:
                return &bpf_l3_csum_replace_proto;
        case BPF_FUNC_l4_csum_replace:
                return &bpf_l4_csum_replace_proto;
        case BPF_FUNC_set_hash_invalid:
                return &bpf_set_hash_invalid_proto;
        case BPF_FUNC_lwt_push_encap:
                return &bpf_lwt_xmit_push_encap_proto;
        default:
                return lwt_out_func_proto(func_id, prog);
        }
}

static const struct bpf_func_proto *
lwt_seg6local_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
        switch (func_id) {
#if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
        case BPF_FUNC_lwt_seg6_store_bytes:
                return &bpf_lwt_seg6_store_bytes_proto;
        case BPF_FUNC_lwt_seg6_action:
                return &bpf_lwt_seg6_action_proto;
        case BPF_FUNC_lwt_seg6_adjust_srh:
                return &bpf_lwt_seg6_adjust_srh_proto;
#endif
        default:
                return lwt_out_func_proto(func_id, prog);
        }
}

static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type,
                                    const struct bpf_prog *prog,
                                    struct bpf_insn_access_aux *info)
{
        const int size_default = sizeof(__u32);

        if (off < 0 || off >= sizeof(struct __sk_buff))
                return false;

        /* The verifier guarantees that size > 0. */
        if (off % size != 0)
                return false;

        switch (off) {
        case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
                if (off + size > offsetofend(struct __sk_buff, cb[4]))
                        return false;
                break;
        case bpf_ctx_range(struct __sk_buff, data):
        case bpf_ctx_range(struct __sk_buff, data_meta):
        case bpf_ctx_range(struct __sk_buff, data_end):
                if (info->is_ldsx || size != size_default)
                        return false;
                break;
        case bpf_ctx_range_till(struct __sk_buff, remote_ip6[0], remote_ip6[3]):
        case bpf_ctx_range_till(struct __sk_buff, local_ip6[0], local_ip6[3]):
        case bpf_ctx_range_till(struct __sk_buff, remote_ip4, remote_ip4):
        case bpf_ctx_range_till(struct __sk_buff, local_ip4, local_ip4):
                if (size != size_default)
                        return false;
                break;
        case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
                return false;
        case bpf_ctx_range(struct __sk_buff, hwtstamp):
                if (type == BPF_WRITE || size != sizeof(__u64))
                        return false;
                break;
        case bpf_ctx_range(struct __sk_buff, tstamp):
                if (size != sizeof(__u64))
                        return false;
                break;
        case bpf_ctx_range_ptr(struct __sk_buff, sk):
                if (type == BPF_WRITE || size != sizeof(__u64))
                        return false;
                info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL;
                break;
        case offsetof(struct __sk_buff, tstamp_type):
                return false;
        case offsetofend(struct __sk_buff, tstamp_type) ... offsetof(struct __sk_buff, hwtstamp) - 1:
                /* Explicitly prohibit access to padding in __sk_buff. */
                return false;
        default:
                /* Only narrow read access allowed for now. */
                if (type == BPF_WRITE) {
                        if (size != size_default)
                                return false;
                } else {
                        bpf_ctx_record_field_size(info, size_default);
                        if (!bpf_ctx_narrow_access_ok(off, size, size_default))
                                return false;
                }
        }

        return true;
}

static bool sk_filter_is_valid_access(int off, int size,
                                      enum bpf_access_type type,
                                      const struct bpf_prog *prog,
                                      struct bpf_insn_access_aux *info)
{
        switch (off) {
        case bpf_ctx_range(struct __sk_buff, tc_classid):
        case bpf_ctx_range(struct __sk_buff, data):
        case bpf_ctx_range(struct __sk_buff, data_meta):
        case bpf_ctx_range(struct __sk_buff, data_end):
        case bpf_ctx_range_till(struct __sk_buff, family, local_port):
        case bpf_ctx_range(struct __sk_buff, tstamp):
        case bpf_ctx_range(struct __sk_buff, wire_len):
        case bpf_ctx_range(struct __sk_buff, hwtstamp):
                return false;
        }

        if (type == BPF_WRITE) {
                switch (off) {
                case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
                        break;
                default:
                        return false;
                }
        }

        return bpf_skb_is_valid_access(off, size, type, prog, info);
}

static bool cg_skb_is_valid_access(int off, int size,
                                   enum bpf_access_type type,
                                   const struct bpf_prog *prog,
                                   struct bpf_insn_access_aux *info)
{
        switch (off) {
        case bpf_ctx_range(struct __sk_buff, tc_classid):
        case bpf_ctx_range(struct __sk_buff, data_meta):
        case bpf_ctx_range(struct __sk_buff, wire_len):
                return false;
        case bpf_ctx_range(struct __sk_buff, data):
        case bpf_ctx_range(struct __sk_buff, data_end):
                if (!bpf_token_capable(prog->aux->token, CAP_BPF))
                        return false;
                break;
        }

        if (type == BPF_WRITE) {
                switch (off) {
                case bpf_ctx_range(struct __sk_buff, mark):
                case bpf_ctx_range(struct __sk_buff, priority):
                case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
                        break;
                case bpf_ctx_range(struct __sk_buff, tstamp):
                        if (!bpf_token_capable(prog->aux->token, CAP_BPF))
                                return false;
                        break;
                default:
                        return false;
                }
        }

        switch (off) {
        case bpf_ctx_range(struct __sk_buff, data):
                info->reg_type = PTR_TO_PACKET;
                break;
        case bpf_ctx_range(struct __sk_buff, data_end):
                info->reg_type = PTR_TO_PACKET_END;
                break;
        }

        return bpf_skb_is_valid_access(off, size, type, prog, info);
}

static bool lwt_is_valid_access(int off, int size,
                                enum bpf_access_type type,
                                const struct bpf_prog *prog,
                                struct bpf_insn_access_aux *info)
{
        switch (off) {
        case bpf_ctx_range(struct __sk_buff, tc_classid):
        case bpf_ctx_range_till(struct __sk_buff, family, local_port):
        case bpf_ctx_range(struct __sk_buff, data_meta):
        case bpf_ctx_range(struct __sk_buff, tstamp):
        case bpf_ctx_range(struct __sk_buff, wire_len):
        case bpf_ctx_range(struct __sk_buff, hwtstamp):
                return false;
        }

        if (type == BPF_WRITE) {
                switch (off) {
                case bpf_ctx_range(struct __sk_buff, mark):
                case bpf_ctx_range(struct __sk_buff, priority):
                case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
                        break;
                default:
                        return false;
                }
        }

        switch (off) {
        case bpf_ctx_range(struct __sk_buff, data):
                info->reg_type = PTR_TO_PACKET;
                break;
        case bpf_ctx_range(struct __sk_buff, data_end):
                info->reg_type = PTR_TO_PACKET_END;
                break;
        }

        return bpf_skb_is_valid_access(off, size, type, prog, info);
}

/* Attach type specific accesses */
static bool __sock_filter_check_attach_type(int off,
                                            enum bpf_access_type access_type,
                                            enum bpf_attach_type attach_type)
{
        switch (off) {
        case offsetof(struct bpf_sock, bound_dev_if):
        case offsetof(struct bpf_sock, mark):
        case offsetof(struct bpf_sock, priority):
                switch (attach_type) {
                case BPF_CGROUP_INET_SOCK_CREATE:
                case BPF_CGROUP_INET_SOCK_RELEASE:
                        goto full_access;
                default:
                        return false;
                }
        case bpf_ctx_range(struct bpf_sock, src_ip4):
                switch (attach_type) {
                case BPF_CGROUP_INET4_POST_BIND:
                        goto read_only;
                default:
                        return false;
                }
        case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
                switch (attach_type) {
                case BPF_CGROUP_INET6_POST_BIND:
                        goto read_only;
                default:
                        return false;
                }
        case bpf_ctx_range(struct bpf_sock, src_port):
                switch (attach_type) {
                case BPF_CGROUP_INET4_POST_BIND:
                case BPF_CGROUP_INET6_POST_BIND:
                        goto read_only;
                default:
                        return false;
                }
        }
read_only:
        return access_type == BPF_READ;
full_access:
        return true;
}

bool bpf_sock_common_is_valid_access(int off, int size,
                                     enum bpf_access_type type,
                                     struct bpf_insn_access_aux *info)
{
        switch (off) {
        case bpf_ctx_range_till(struct bpf_sock, type, priority):
                return false;
        default:
                return bpf_sock_is_valid_access(off, size, type, info);
        }
}

bool bpf_sock_is_valid_access(int off, int size, enum bpf_access_type type,
                              struct bpf_insn_access_aux *info)
{
        const int size_default = sizeof(__u32);
        int field_size;

        if (off < 0 || off >= sizeof(struct bpf_sock))
                return false;
        if (off % size != 0)
                return false;

        switch (off) {
        case offsetof(struct bpf_sock, state):
        case offsetof(struct bpf_sock, family):
        case offsetof(struct bpf_sock, type):
        case offsetof(struct bpf_sock, protocol):
        case offsetof(struct bpf_sock, src_port):
        case offsetof(struct bpf_sock, rx_queue_mapping):
        case bpf_ctx_range(struct bpf_sock, src_ip4):
        case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
        case bpf_ctx_range(struct bpf_sock, dst_ip4):
        case bpf_ctx_range_till(struct bpf_sock, dst_ip6[0], dst_ip6[3]):
                bpf_ctx_record_field_size(info, size_default);
                return bpf_ctx_narrow_access_ok(off, size, size_default);
        case bpf_ctx_range(struct bpf_sock, dst_port):
                field_size = size == size_default ?
                        size_default : sizeof_field(struct bpf_sock, dst_port);
                bpf_ctx_record_field_size(info, field_size);
                return bpf_ctx_narrow_access_ok(off, size, field_size);
        case offsetofend(struct bpf_sock, dst_port) ...
             offsetof(struct bpf_sock, dst_ip4) - 1:
                return false;
        }

        return size == size_default;
}

static bool sock_filter_is_valid_access(int off, int size,
                                        enum bpf_access_type type,
                                        const struct bpf_prog *prog,
                                        struct bpf_insn_access_aux *info)
{
        if (!bpf_sock_is_valid_access(off, size, type, info))
                return false;
        return __sock_filter_check_attach_type(off, type,
                                               prog->expected_attach_type);
}

static int bpf_noop_prologue(struct bpf_insn *insn_buf, bool direct_write,
                             const struct bpf_prog *prog)
{
        /* Neither direct read nor direct write requires any preliminary
         * action.
         */
        return 0;
}

static int bpf_unclone_prologue(struct bpf_insn *insn_buf, bool direct_write,
                                const struct bpf_prog *prog, int drop_verdict)
{
        struct bpf_insn *insn = insn_buf;

        if (!direct_write)
                return 0;

        /* if (!skb->cloned)
         *       goto start;
         *
         * (Fast-path, otherwise approximation that we might be
         *  a clone, do the rest in helper.)
         */
        *insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_6, BPF_REG_1, CLONED_OFFSET);
        *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_6, CLONED_MASK);
        *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 7);

        /* ret = bpf_skb_pull_data(skb, 0); */
        *insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
        *insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_2, BPF_REG_2);
        *insn++ = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
                               BPF_FUNC_skb_pull_data);
        /* if (!ret)
         *      goto restore;
         * return TC_ACT_SHOT;
         */
        *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2);
        *insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, drop_verdict);
        *insn++ = BPF_EXIT_INSN();

        /* restore: */
        *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
        /* start: */
        *insn++ = prog->insnsi[0];

        return insn - insn_buf;
}

static int bpf_gen_ld_abs(const struct bpf_insn *orig,
                          struct bpf_insn *insn_buf)
{
        bool indirect = BPF_MODE(orig->code) == BPF_IND;
        struct bpf_insn *insn = insn_buf;

        if (!indirect) {
                *insn++ = BPF_MOV64_IMM(BPF_REG_2, orig->imm);
        } else {
                *insn++ = BPF_MOV64_REG(BPF_REG_2, orig->src_reg);
                if (orig->imm)
                        *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, orig->imm);
        }
        /* We're guaranteed here that CTX is in R6. */
        *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_CTX);

        switch (BPF_SIZE(orig->code)) {
        case BPF_B:
                *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8_no_cache);
                break;
        case BPF_H:
                *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16_no_cache);
                break;
        case BPF_W:
                *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32_no_cache);
                break;
        }

        *insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_0, 0, 2);
        *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_0, BPF_REG_0);
        *insn++ = BPF_EXIT_INSN();

        return insn - insn_buf;
}

static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write,
                               const struct bpf_prog *prog)
{
        return bpf_unclone_prologue(insn_buf, direct_write, prog, TC_ACT_SHOT);
}

static bool tc_cls_act_is_valid_access(int off, int size,
                                       enum bpf_access_type type,
                                       const struct bpf_prog *prog,
                                       struct bpf_insn_access_aux *info)
{
        if (type == BPF_WRITE) {
                switch (off) {
                case bpf_ctx_range(struct __sk_buff, mark):
                case bpf_ctx_range(struct __sk_buff, tc_index):
                case bpf_ctx_range(struct __sk_buff, priority):
                case bpf_ctx_range(struct __sk_buff, tc_classid):
                case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
                case bpf_ctx_range(struct __sk_buff, tstamp):
                case bpf_ctx_range(struct __sk_buff, queue_mapping):
                        break;
                default:
                        return false;
                }
        }

        switch (off) {
        case bpf_ctx_range(struct __sk_buff, data):
                info->reg_type = PTR_TO_PACKET;
                break;
        case bpf_ctx_range(struct __sk_buff, data_meta):
                info->reg_type = PTR_TO_PACKET_META;
                break;
        case bpf_ctx_range(struct __sk_buff, data_end):
                info->reg_type = PTR_TO_PACKET_END;
                break;
        case bpf_ctx_range_till(struct __sk_buff, family, local_port):
                return false;
        case offsetof(struct __sk_buff, tstamp_type):
                /* The convert_ctx_access() on reading and writing
                 * __sk_buff->tstamp depends on whether the bpf prog
                 * has used __sk_buff->tstamp_type or not.
                 * Thus, we need to set prog->tstamp_type_access
                 * earlier during is_valid_access() here.
                 */
                ((struct bpf_prog *)prog)->tstamp_type_access = 1;
                return size == sizeof(__u8);
        }

        return bpf_skb_is_valid_access(off, size, type, prog, info);
}

DEFINE_MUTEX(nf_conn_btf_access_lock);
EXPORT_SYMBOL_GPL(nf_conn_btf_access_lock);

int (*nfct_btf_struct_access)(struct bpf_verifier_log *log,
                              const struct bpf_reg_state *reg,
                              int off, int size);
EXPORT_SYMBOL_GPL(nfct_btf_struct_access);

static int tc_cls_act_btf_struct_access(struct bpf_verifier_log *log,
                                        const struct bpf_reg_state *reg,
                                        int off, int size)
{
        int ret = -EACCES;

        mutex_lock(&nf_conn_btf_access_lock);
        if (nfct_btf_struct_access)
                ret = nfct_btf_struct_access(log, reg, off, size);
        mutex_unlock(&nf_conn_btf_access_lock);

        return ret;
}

static bool __is_valid_xdp_access(int off, int size)
{
        if (off < 0 || off >= sizeof(struct xdp_md))
                return false;
        if (off % size != 0)
                return false;
        if (size != sizeof(__u32))
                return false;

        return true;
}

static bool xdp_is_valid_access(int off, int size,
                                enum bpf_access_type type,
                                const struct bpf_prog *prog,
                                struct bpf_insn_access_aux *info)
{
        if (prog->expected_attach_type != BPF_XDP_DEVMAP) {
                switch (off) {
                case offsetof(struct xdp_md, egress_ifindex):
                        return false;
                }
        }

        if (type == BPF_WRITE) {
                if (bpf_prog_is_offloaded(prog->aux)) {
                        switch (off) {
                        case offsetof(struct xdp_md, rx_queue_index):
                                return __is_valid_xdp_access(off, size);
                        }
                }
                return false;
        } else {
                switch (off) {
                case offsetof(struct xdp_md, data_meta):
                case offsetof(struct xdp_md, data):
                case offsetof(struct xdp_md, data_end):
                        if (info->is_ldsx)
                                return false;
                }
        }

        switch (off) {
        case offsetof(struct xdp_md, data):
                info->reg_type = PTR_TO_PACKET;
                break;
        case offsetof(struct xdp_md, data_meta):
                info->reg_type = PTR_TO_PACKET_META;
                break;
        case offsetof(struct xdp_md, data_end):
                info->reg_type = PTR_TO_PACKET_END;
                break;
        }

        return __is_valid_xdp_access(off, size);
}

void bpf_warn_invalid_xdp_action(const struct net_device *dev,
                                 const struct bpf_prog *prog, u32 act)
{
        const u32 act_max = XDP_REDIRECT;

        pr_warn_once("%s XDP return value %u on prog %s (id %d) dev %s, expect packet loss!\n",
                     act > act_max ? "Illegal" : "Driver unsupported",
                     act, prog->aux->name, prog->aux->id, dev ? dev->name : "N/A");
}
EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);

static int xdp_btf_struct_access(struct bpf_verifier_log *log,
                                 const struct bpf_reg_state *reg,
                                 int off, int size)
{
        int ret = -EACCES;

        mutex_lock(&nf_conn_btf_access_lock);
        if (nfct_btf_struct_access)
                ret = nfct_btf_struct_access(log, reg, off, size);
        mutex_unlock(&nf_conn_btf_access_lock);

        return ret;
}

static bool sock_addr_is_valid_access(int off, int size,
                                      enum bpf_access_type type,
                                      const struct bpf_prog *prog,
                                      struct bpf_insn_access_aux *info)
{
        const int size_default = sizeof(__u32);

        if (off < 0 || off >= sizeof(struct bpf_sock_addr))
                return false;
        if (off % size != 0)
                return false;

        /* Disallow access to fields not belonging to the attach type's address
         * family.
         */
        switch (off) {
        case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
                switch (prog->expected_attach_type) {
                case BPF_CGROUP_INET4_BIND:
                case BPF_CGROUP_INET4_CONNECT:
                case BPF_CGROUP_INET4_GETPEERNAME:
                case BPF_CGROUP_INET4_GETSOCKNAME:
                case BPF_CGROUP_UDP4_SENDMSG:
                case BPF_CGROUP_UDP4_RECVMSG:
                        break;
                default:
                        return false;
                }
                break;
        case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
                switch (prog->expected_attach_type) {
                case BPF_CGROUP_INET6_BIND:
                case BPF_CGROUP_INET6_CONNECT:
                case BPF_CGROUP_INET6_GETPEERNAME:
                case BPF_CGROUP_INET6_GETSOCKNAME:
                case BPF_CGROUP_UDP6_SENDMSG:
                case BPF_CGROUP_UDP6_RECVMSG:
                        break;
                default:
                        return false;
                }
                break;
        case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4):
                switch (prog->expected_attach_type) {
                case BPF_CGROUP_UDP4_SENDMSG:
                        break;
                default:
                        return false;
                }
                break;
        case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
                                msg_src_ip6[3]):
                switch (prog->expected_attach_type) {
                case BPF_CGROUP_UDP6_SENDMSG:
                        break;
                default:
                        return false;
                }
                break;
        }

        switch (off) {
        case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
        case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
        case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4):
        case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
                                msg_src_ip6[3]):
        case bpf_ctx_range(struct bpf_sock_addr, user_port):
                if (type == BPF_READ) {
                        bpf_ctx_record_field_size(info, size_default);

                        if (bpf_ctx_wide_access_ok(off, size,
                                                   struct bpf_sock_addr,
                                                   user_ip6))
                                return true;

                        if (bpf_ctx_wide_access_ok(off, size,
                                                   struct bpf_sock_addr,
                                                   msg_src_ip6))
                                return true;

                        if (!bpf_ctx_narrow_access_ok(off, size, size_default))
                                return false;
                } else {
                        if (bpf_ctx_wide_access_ok(off, size,
                                                   struct bpf_sock_addr,
                                                   user_ip6))
                                return true;

                        if (bpf_ctx_wide_access_ok(off, size,
                                                   struct bpf_sock_addr,
                                                   msg_src_ip6))
                                return true;

                        if (size != size_default)
                                return false;
                }
                break;
        case bpf_ctx_range_ptr(struct bpf_sock_addr, sk):
                if (type != BPF_READ)
                        return false;
                if (size != sizeof(__u64))
                        return false;
                info->reg_type = PTR_TO_SOCKET;
                break;
        case bpf_ctx_range(struct bpf_sock_addr, user_family):
        case bpf_ctx_range(struct bpf_sock_addr, family):
        case bpf_ctx_range(struct bpf_sock_addr, type):
        case bpf_ctx_range(struct bpf_sock_addr, protocol):
                if (type != BPF_READ)
                        return false;
                if (size != size_default)
                        return false;
                break;
        default:
                return false;
        }

        return true;
}

static bool sock_ops_is_valid_access(int off, int size,
                                     enum bpf_access_type type,
                                     const struct bpf_prog *prog,
                                     struct bpf_insn_access_aux *info)
{
        const int size_default = sizeof(__u32);

        if (off < 0 || off >= sizeof(struct bpf_sock_ops))
                return false;

        /* The verifier guarantees that size > 0. */
        if (off % size != 0)
                return false;

        if (type == BPF_WRITE) {
                switch (off) {
                case offsetof(struct bpf_sock_ops, reply):
                case offsetof(struct bpf_sock_ops, sk_txhash):
                        if (size != size_default)
                                return false;
                        break;
                default:
                        return false;
                }
        } else {
                switch (off) {
                case bpf_ctx_range_till(struct bpf_sock_ops, bytes_received,
                                        bytes_acked):
                        if (size != sizeof(__u64))
                                return false;
                        break;
                case bpf_ctx_range_ptr(struct bpf_sock_ops, sk):
                        if (size != sizeof(__u64))
                                return false;
                        info->reg_type = PTR_TO_SOCKET_OR_NULL;
                        break;
                case bpf_ctx_range_ptr(struct bpf_sock_ops, skb_data):
                        if (size != sizeof(__u64))
                                return false;
                        info->reg_type = PTR_TO_PACKET;
                        break;
                case bpf_ctx_range_ptr(struct bpf_sock_ops, skb_data_end):
                        if (size != sizeof(__u64))
                                return false;
                        info->reg_type = PTR_TO_PACKET_END;
                        break;
                case offsetof(struct bpf_sock_ops, skb_tcp_flags):
                        bpf_ctx_record_field_size(info, size_default);
                        return bpf_ctx_narrow_access_ok(off, size,
                                                        size_default);
                case bpf_ctx_range(struct bpf_sock_ops, skb_hwtstamp):
                        if (size != sizeof(__u64))
                                return false;
                        break;
                default:
                        if (size != size_default)
                                return false;
                        break;
                }
        }

        return true;
}

static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write,
                           const struct bpf_prog *prog)
{
        return bpf_unclone_prologue(insn_buf, direct_write, prog, SK_DROP);
}

static bool sk_skb_is_valid_access(int off, int size,
                                   enum bpf_access_type type,
                                   const struct bpf_prog *prog,
                                   struct bpf_insn_access_aux *info)
{
        switch (off) {
        case bpf_ctx_range(struct __sk_buff, tc_classid):
        case bpf_ctx_range(struct __sk_buff, data_meta):
        case bpf_ctx_range(struct __sk_buff, tstamp):
        case bpf_ctx_range(struct __sk_buff, wire_len):
        case bpf_ctx_range(struct __sk_buff, hwtstamp):
                return false;
        }

        if (type == BPF_WRITE) {
                switch (off) {
                case bpf_ctx_range(struct __sk_buff, tc_index):
                case bpf_ctx_range(struct __sk_buff, priority):
                        break;
                default:
                        return false;
                }
        }

        switch (off) {
        case bpf_ctx_range(struct __sk_buff, mark):
                return false;
        case bpf_ctx_range(struct __sk_buff, data):
                info->reg_type = PTR_TO_PACKET;
                break;
        case bpf_ctx_range(struct __sk_buff, data_end):
                info->reg_type = PTR_TO_PACKET_END;
                break;
        }

        return bpf_skb_is_valid_access(off, size, type, prog, info);
}

static bool sk_msg_is_valid_access(int off, int size,
                                   enum bpf_access_type type,
                                   const struct bpf_prog *prog,
                                   struct bpf_insn_access_aux *info)
{
        if (type == BPF_WRITE)
                return false;

        if (off % size != 0)
                return false;

        switch (off) {
        case bpf_ctx_range_ptr(struct sk_msg_md, data):
                info->reg_type = PTR_TO_PACKET;
                if (size != sizeof(__u64))
                        return false;
                break;
        case bpf_ctx_range_ptr(struct sk_msg_md, data_end):
                info->reg_type = PTR_TO_PACKET_END;
                if (size != sizeof(__u64))
                        return false;
                break;
        case bpf_ctx_range_ptr(struct sk_msg_md, sk):
                if (size != sizeof(__u64))
                        return false;
                info->reg_type = PTR_TO_SOCKET;
                break;
        case bpf_ctx_range(struct sk_msg_md, family):
        case bpf_ctx_range(struct sk_msg_md, remote_ip4):
        case bpf_ctx_range(struct sk_msg_md, local_ip4):
        case bpf_ctx_range_till(struct sk_msg_md, remote_ip6[0], remote_ip6[3]):
        case bpf_ctx_range_till(struct sk_msg_md, local_ip6[0], local_ip6[3]):
        case bpf_ctx_range(struct sk_msg_md, remote_port):
        case bpf_ctx_range(struct sk_msg_md, local_port):
        case bpf_ctx_range(struct sk_msg_md, size):
                if (size != sizeof(__u32))
                        return false;
                break;
        default:
                return false;
        }
        return true;
}

static bool flow_dissector_is_valid_access(int off, int size,
                                           enum bpf_access_type type,
                                           const struct bpf_prog *prog,
                                           struct bpf_insn_access_aux *info)
{
        const int size_default = sizeof(__u32);

        if (off < 0 || off >= sizeof(struct __sk_buff))
                return false;

        if (off % size != 0)
                return false;

        if (type == BPF_WRITE)
                return false;

        switch (off) {
        case bpf_ctx_range(struct __sk_buff, data):
                if (info->is_ldsx || size != size_default)
                        return false;
                info->reg_type = PTR_TO_PACKET;
                return true;
        case bpf_ctx_range(struct __sk_buff, data_end):
                if (info->is_ldsx || size != size_default)
                        return false;
                info->reg_type = PTR_TO_PACKET_END;
                return true;
        case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
                if (size != sizeof(__u64))
                        return false;
                info->reg_type = PTR_TO_FLOW_KEYS;
                return true;
        default:
                return false;
        }
}

static u32 flow_dissector_convert_ctx_access(enum bpf_access_type type,
                                             const struct bpf_insn *si,
                                             struct bpf_insn *insn_buf,
                                             struct bpf_prog *prog,
                                             u32 *target_size)

{
        struct bpf_insn *insn = insn_buf;

        switch (si->off) {
        case offsetof(struct __sk_buff, data):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, data),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_flow_dissector, data));
                break;

        case offsetof(struct __sk_buff, data_end):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, data_end),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_flow_dissector, data_end));
                break;

        case offsetof(struct __sk_buff, flow_keys):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, flow_keys),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_flow_dissector, flow_keys));
                break;
        }

        return insn - insn_buf;
}

static struct bpf_insn *bpf_convert_tstamp_type_read(const struct bpf_insn *si,
                                                     struct bpf_insn *insn)
{
        __u8 value_reg = si->dst_reg;
        __u8 skb_reg = si->src_reg;
        BUILD_BUG_ON(__SKB_CLOCK_MAX != (int)BPF_SKB_CLOCK_TAI);
        BUILD_BUG_ON(SKB_CLOCK_REALTIME != (int)BPF_SKB_CLOCK_REALTIME);
        BUILD_BUG_ON(SKB_CLOCK_MONOTONIC != (int)BPF_SKB_CLOCK_MONOTONIC);
        BUILD_BUG_ON(SKB_CLOCK_TAI != (int)BPF_SKB_CLOCK_TAI);
        *insn++ = BPF_LDX_MEM(BPF_B, value_reg, skb_reg, SKB_BF_MONO_TC_OFFSET);
        *insn++ = BPF_ALU32_IMM(BPF_AND, value_reg, SKB_TSTAMP_TYPE_MASK);
#ifdef __BIG_ENDIAN_BITFIELD
        *insn++ = BPF_ALU32_IMM(BPF_RSH, value_reg, SKB_TSTAMP_TYPE_RSHIFT);
#else
        BUILD_BUG_ON(!(SKB_TSTAMP_TYPE_MASK & 0x1));
#endif

        return insn;
}

static struct bpf_insn *bpf_convert_shinfo_access(__u8 dst_reg, __u8 skb_reg,
                                                  struct bpf_insn *insn)
{
        /* si->dst_reg = skb_shinfo(SKB); */
#ifdef NET_SKBUFF_DATA_USES_OFFSET
        *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, end),
                              BPF_REG_AX, skb_reg,
                              offsetof(struct sk_buff, end));
        *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, head),
                              dst_reg, skb_reg,
                              offsetof(struct sk_buff, head));
        *insn++ = BPF_ALU64_REG(BPF_ADD, dst_reg, BPF_REG_AX);
#else
        *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, end),
                              dst_reg, skb_reg,
                              offsetof(struct sk_buff, end));
#endif

        return insn;
}

static struct bpf_insn *bpf_convert_tstamp_read(const struct bpf_prog *prog,
                                                const struct bpf_insn *si,
                                                struct bpf_insn *insn)
{
        __u8 value_reg = si->dst_reg;
        __u8 skb_reg = si->src_reg;

#ifdef CONFIG_NET_XGRESS
        /* If the tstamp_type is read,
         * the bpf prog is aware the tstamp could have delivery time.
         * Thus, read skb->tstamp as is if tstamp_type_access is true.
         */
        if (!prog->tstamp_type_access) {
                /* AX is needed because src_reg and dst_reg could be the same */
                __u8 tmp_reg = BPF_REG_AX;

                *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, SKB_BF_MONO_TC_OFFSET);
                /* check if ingress mask bits is set */
                *insn++ = BPF_JMP32_IMM(BPF_JSET, tmp_reg, TC_AT_INGRESS_MASK, 1);
                *insn++ = BPF_JMP_A(4);
                *insn++ = BPF_JMP32_IMM(BPF_JSET, tmp_reg, SKB_TSTAMP_TYPE_MASK, 1);
                *insn++ = BPF_JMP_A(2);
                /* skb->tc_at_ingress && skb->tstamp_type,
                 * read 0 as the (rcv) timestamp.
                 */
                *insn++ = BPF_MOV64_IMM(value_reg, 0);
                *insn++ = BPF_JMP_A(1);
        }
#endif

        *insn++ = BPF_LDX_MEM(BPF_DW, value_reg, skb_reg,
                              offsetof(struct sk_buff, tstamp));
        return insn;
}

static struct bpf_insn *bpf_convert_tstamp_write(const struct bpf_prog *prog,
                                                 const struct bpf_insn *si,
                                                 struct bpf_insn *insn)
{
        __u8 value_reg = si->src_reg;
        __u8 skb_reg = si->dst_reg;

#ifdef CONFIG_NET_XGRESS
        /* If the tstamp_type is read,
         * the bpf prog is aware the tstamp could have delivery time.
         * Thus, write skb->tstamp as is if tstamp_type_access is true.
         * Otherwise, writing at ingress will have to clear the
         * skb->tstamp_type bit also.
         */
        if (!prog->tstamp_type_access) {
                __u8 tmp_reg = BPF_REG_AX;

                *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, SKB_BF_MONO_TC_OFFSET);
                /* Writing __sk_buff->tstamp as ingress, goto <clear> */
                *insn++ = BPF_JMP32_IMM(BPF_JSET, tmp_reg, TC_AT_INGRESS_MASK, 1);
                /* goto <store> */
                *insn++ = BPF_JMP_A(2);
                /* <clear>: skb->tstamp_type */
                *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, ~SKB_TSTAMP_TYPE_MASK);
                *insn++ = BPF_STX_MEM(BPF_B, skb_reg, tmp_reg, SKB_BF_MONO_TC_OFFSET);
        }
#endif

        /* <store>: skb->tstamp = tstamp */
        *insn++ = BPF_RAW_INSN(BPF_CLASS(si->code) | BPF_DW | BPF_MEM,
                               skb_reg, value_reg, offsetof(struct sk_buff, tstamp), si->imm);
        return insn;
}

#define BPF_EMIT_STORE(size, si, off)                                   \
        BPF_RAW_INSN(BPF_CLASS((si)->code) | (size) | BPF_MEM,          \
                     (si)->dst_reg, (si)->src_reg, (off), (si)->imm)

static u32 bpf_convert_ctx_access(enum bpf_access_type type,
                                  const struct bpf_insn *si,
                                  struct bpf_insn *insn_buf,
                                  struct bpf_prog *prog, u32 *target_size)
{
        struct bpf_insn *insn = insn_buf;
        int off;

        switch (si->off) {
        case offsetof(struct __sk_buff, len):
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
                                      bpf_target_off(struct sk_buff, len, 4,
                                                     target_size));
                break;

        case offsetof(struct __sk_buff, protocol):
                *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
                                      bpf_target_off(struct sk_buff, protocol, 2,
                                                     target_size));
                break;

        case offsetof(struct __sk_buff, vlan_proto):
                *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
                                      bpf_target_off(struct sk_buff, vlan_proto, 2,
                                                     target_size));
                break;

        case offsetof(struct __sk_buff, priority):
                if (type == BPF_WRITE)
                        *insn++ = BPF_EMIT_STORE(BPF_W, si,
                                                 bpf_target_off(struct sk_buff, priority, 4,
                                                                target_size));
                else
                        *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
                                              bpf_target_off(struct sk_buff, priority, 4,
                                                             target_size));
                break;

        case offsetof(struct __sk_buff, ingress_ifindex):
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
                                      bpf_target_off(struct sk_buff, skb_iif, 4,
                                                     target_size));
                break;

        case offsetof(struct __sk_buff, ifindex):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_buff, dev));
                *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      bpf_target_off(struct net_device, ifindex, 4,
                                                     target_size));
                break;

        case offsetof(struct __sk_buff, hash):
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
                                      bpf_target_off(struct sk_buff, hash, 4,
                                                     target_size));
                break;

        case offsetof(struct __sk_buff, mark):
                if (type == BPF_WRITE)
                        *insn++ = BPF_EMIT_STORE(BPF_W, si,
                                                 bpf_target_off(struct sk_buff, mark, 4,
                                                                target_size));
                else
                        *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
                                              bpf_target_off(struct sk_buff, mark, 4,
                                                             target_size));
                break;

        case offsetof(struct __sk_buff, pkt_type):
                *target_size = 1;
                *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
                                      PKT_TYPE_OFFSET);
                *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, PKT_TYPE_MAX);
#ifdef __BIG_ENDIAN_BITFIELD
                *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 5);
#endif
                break;

        case offsetof(struct __sk_buff, queue_mapping):
                if (type == BPF_WRITE) {
                        u32 offset = bpf_target_off(struct sk_buff, queue_mapping, 2, target_size);

                        if (BPF_CLASS(si->code) == BPF_ST && si->imm >= NO_QUEUE_MAPPING) {
                                *insn++ = BPF_JMP_A(0); /* noop */
                                break;
                        }

                        if (BPF_CLASS(si->code) == BPF_STX)
                                *insn++ = BPF_JMP_IMM(BPF_JGE, si->src_reg, NO_QUEUE_MAPPING, 1);
                        *insn++ = BPF_EMIT_STORE(BPF_H, si, offset);
                } else {
                        *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
                                              bpf_target_off(struct sk_buff,
                                                             queue_mapping,
                                                             2, target_size));
                }
                break;

        case offsetof(struct __sk_buff, vlan_present):
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
                                      bpf_target_off(struct sk_buff,
                                                     vlan_all, 4, target_size));
                *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
                *insn++ = BPF_ALU32_IMM(BPF_MOV, si->dst_reg, 1);
                break;

        case offsetof(struct __sk_buff, vlan_tci):
                *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
                                      bpf_target_off(struct sk_buff, vlan_tci, 2,
                                                     target_size));
                break;

        case offsetof(struct __sk_buff, cb[0]) ...
             offsetofend(struct __sk_buff, cb[4]) - 1:
                BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, data) < 20);
                BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
                              offsetof(struct qdisc_skb_cb, data)) %
                             sizeof(__u64));

                prog->cb_access = 1;
                off  = si->off;
                off -= offsetof(struct __sk_buff, cb[0]);
                off += offsetof(struct sk_buff, cb);
                off += offsetof(struct qdisc_skb_cb, data);
                if (type == BPF_WRITE)
                        *insn++ = BPF_EMIT_STORE(BPF_SIZE(si->code), si, off);
                else
                        *insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
                                              si->src_reg, off);
                break;

        case offsetof(struct __sk_buff, tc_classid):
                BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, tc_classid) != 2);

                off  = si->off;
                off -= offsetof(struct __sk_buff, tc_classid);
                off += offsetof(struct sk_buff, cb);
                off += offsetof(struct qdisc_skb_cb, tc_classid);
                *target_size = 2;
                if (type == BPF_WRITE)
                        *insn++ = BPF_EMIT_STORE(BPF_H, si, off);
                else
                        *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg,
                                              si->src_reg, off);
                break;

        case offsetof(struct __sk_buff, data):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_buff, data));
                break;

        case offsetof(struct __sk_buff, data_meta):
                off  = si->off;
                off -= offsetof(struct __sk_buff, data_meta);
                off += offsetof(struct sk_buff, cb);
                off += offsetof(struct bpf_skb_data_end, data_meta);
                *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
                                      si->src_reg, off);
                break;

        case offsetof(struct __sk_buff, data_end):
                off  = si->off;
                off -= offsetof(struct __sk_buff, data_end);
                off += offsetof(struct sk_buff, cb);
                off += offsetof(struct bpf_skb_data_end, data_end);
                *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
                                      si->src_reg, off);
                break;

        case offsetof(struct __sk_buff, tc_index):
#ifdef CONFIG_NET_SCHED
                if (type == BPF_WRITE)
                        *insn++ = BPF_EMIT_STORE(BPF_H, si,
                                                 bpf_target_off(struct sk_buff, tc_index, 2,
                                                                target_size));
                else
                        *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
                                              bpf_target_off(struct sk_buff, tc_index, 2,
                                                             target_size));
#else
                *target_size = 2;
                if (type == BPF_WRITE)
                        *insn++ = BPF_MOV64_REG(si->dst_reg, si->dst_reg);
                else
                        *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
#endif
                break;

        case offsetof(struct __sk_buff, napi_id):
#if defined(CONFIG_NET_RX_BUSY_POLL)
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
                                      bpf_target_off(struct sk_buff, napi_id, 4,
                                                     target_size));
                *insn++ = BPF_JMP_IMM(BPF_JGE, si->dst_reg, MIN_NAPI_ID, 1);
                *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
#else
                *target_size = 4;
                *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
#endif
                break;
        case offsetof(struct __sk_buff, family):
                BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_buff, sk));
                *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
                                      bpf_target_off(struct sock_common,
                                                     skc_family,
                                                     2, target_size));
                break;
        case offsetof(struct __sk_buff, remote_ip4):
                BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_buff, sk));
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      bpf_target_off(struct sock_common,
                                                     skc_daddr,
                                                     4, target_size));
                break;
        case offsetof(struct __sk_buff, local_ip4):
                BUILD_BUG_ON(sizeof_field(struct sock_common,
                                          skc_rcv_saddr) != 4);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_buff, sk));
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      bpf_target_off(struct sock_common,
                                                     skc_rcv_saddr,
                                                     4, target_size));
                break;
        case offsetof(struct __sk_buff, remote_ip6[0]) ...
             offsetof(struct __sk_buff, remote_ip6[3]):
#if IS_ENABLED(CONFIG_IPV6)
                BUILD_BUG_ON(sizeof_field(struct sock_common,
                                          skc_v6_daddr.s6_addr32[0]) != 4);

                off = si->off;
                off -= offsetof(struct __sk_buff, remote_ip6[0]);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_buff, sk));
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      offsetof(struct sock_common,
                                               skc_v6_daddr.s6_addr32[0]) +
                                      off);
#else
                *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
#endif
                break;
        case offsetof(struct __sk_buff, local_ip6[0]) ...
             offsetof(struct __sk_buff, local_ip6[3]):
#if IS_ENABLED(CONFIG_IPV6)
                BUILD_BUG_ON(sizeof_field(struct sock_common,
                                          skc_v6_rcv_saddr.s6_addr32[0]) != 4);

                off = si->off;
                off -= offsetof(struct __sk_buff, local_ip6[0]);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_buff, sk));
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      offsetof(struct sock_common,
                                               skc_v6_rcv_saddr.s6_addr32[0]) +
                                      off);
#else
                *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
#endif
                break;

        case offsetof(struct __sk_buff, remote_port):
                BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_buff, sk));
                *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
                                      bpf_target_off(struct sock_common,
                                                     skc_dport,
                                                     2, target_size));
#ifndef __BIG_ENDIAN_BITFIELD
                *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
#endif
                break;

        case offsetof(struct __sk_buff, local_port):
                BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_buff, sk));
                *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
                                      bpf_target_off(struct sock_common,
                                                     skc_num, 2, target_size));
                break;

        case offsetof(struct __sk_buff, tstamp):
                BUILD_BUG_ON(sizeof_field(struct sk_buff, tstamp) != 8);

                if (type == BPF_WRITE)
                        insn = bpf_convert_tstamp_write(prog, si, insn);
                else
                        insn = bpf_convert_tstamp_read(prog, si, insn);
                break;

        case offsetof(struct __sk_buff, tstamp_type):
                insn = bpf_convert_tstamp_type_read(si, insn);
                break;

        case offsetof(struct __sk_buff, gso_segs):
                insn = bpf_convert_shinfo_access(si->dst_reg, si->src_reg, insn);
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct skb_shared_info, gso_segs),
                                      si->dst_reg, si->dst_reg,
                                      bpf_target_off(struct skb_shared_info,
                                                     gso_segs, 2,
                                                     target_size));
                break;
        case offsetof(struct __sk_buff, gso_size):
                insn = bpf_convert_shinfo_access(si->dst_reg, si->src_reg, insn);
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct skb_shared_info, gso_size),
                                      si->dst_reg, si->dst_reg,
                                      bpf_target_off(struct skb_shared_info,
                                                     gso_size, 2,
                                                     target_size));
                break;
        case offsetof(struct __sk_buff, wire_len):
                BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, pkt_len) != 4);

                off = si->off;
                off -= offsetof(struct __sk_buff, wire_len);
                off += offsetof(struct sk_buff, cb);
                off += offsetof(struct qdisc_skb_cb, pkt_len);
                *target_size = 4;
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, off);
                break;

        case offsetof(struct __sk_buff, sk):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_buff, sk));
                break;
        case offsetof(struct __sk_buff, hwtstamp):
                BUILD_BUG_ON(sizeof_field(struct skb_shared_hwtstamps, hwtstamp) != 8);
                BUILD_BUG_ON(offsetof(struct skb_shared_hwtstamps, hwtstamp) != 0);

                insn = bpf_convert_shinfo_access(si->dst_reg, si->src_reg, insn);
                *insn++ = BPF_LDX_MEM(BPF_DW,
                                      si->dst_reg, si->dst_reg,
                                      bpf_target_off(struct skb_shared_info,
                                                     hwtstamps, 8,
                                                     target_size));
                break;
        }

        return insn - insn_buf;
}

u32 bpf_sock_convert_ctx_access(enum bpf_access_type type,
                                const struct bpf_insn *si,
                                struct bpf_insn *insn_buf,
                                struct bpf_prog *prog, u32 *target_size)
{
        struct bpf_insn *insn = insn_buf;
        int off;

        switch (si->off) {
        case offsetof(struct bpf_sock, bound_dev_if):
                BUILD_BUG_ON(sizeof_field(struct sock, sk_bound_dev_if) != 4);

                if (type == BPF_WRITE)
                        *insn++ = BPF_EMIT_STORE(BPF_W, si,
                                                 offsetof(struct sock, sk_bound_dev_if));
                else
                        *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
                                      offsetof(struct sock, sk_bound_dev_if));
                break;

        case offsetof(struct bpf_sock, mark):
                BUILD_BUG_ON(sizeof_field(struct sock, sk_mark) != 4);

                if (type == BPF_WRITE)
                        *insn++ = BPF_EMIT_STORE(BPF_W, si,
                                                 offsetof(struct sock, sk_mark));
                else
                        *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
                                      offsetof(struct sock, sk_mark));
                break;

        case offsetof(struct bpf_sock, priority):
                BUILD_BUG_ON(sizeof_field(struct sock, sk_priority) != 4);

                if (type == BPF_WRITE)
                        *insn++ = BPF_EMIT_STORE(BPF_W, si,
                                                 offsetof(struct sock, sk_priority));
                else
                        *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
                                      offsetof(struct sock, sk_priority));
                break;

        case offsetof(struct bpf_sock, family):
                *insn++ = BPF_LDX_MEM(
                        BPF_FIELD_SIZEOF(struct sock_common, skc_family),
                        si->dst_reg, si->src_reg,
                        bpf_target_off(struct sock_common,
                                       skc_family,
                                       sizeof_field(struct sock_common,
                                                    skc_family),
                                       target_size));
                break;

        case offsetof(struct bpf_sock, type):
                *insn++ = BPF_LDX_MEM(
                        BPF_FIELD_SIZEOF(struct sock, sk_type),
                        si->dst_reg, si->src_reg,
                        bpf_target_off(struct sock, sk_type,
                                       sizeof_field(struct sock, sk_type),
                                       target_size));
                break;

        case offsetof(struct bpf_sock, protocol):
                *insn++ = BPF_LDX_MEM(
                        BPF_FIELD_SIZEOF(struct sock, sk_protocol),
                        si->dst_reg, si->src_reg,
                        bpf_target_off(struct sock, sk_protocol,
                                       sizeof_field(struct sock, sk_protocol),
                                       target_size));
                break;

        case offsetof(struct bpf_sock, src_ip4):
                *insn++ = BPF_LDX_MEM(
                        BPF_SIZE(si->code), si->dst_reg, si->src_reg,
                        bpf_target_off(struct sock_common, skc_rcv_saddr,
                                       sizeof_field(struct sock_common,
                                                    skc_rcv_saddr),
                                       target_size));
                break;

        case offsetof(struct bpf_sock, dst_ip4):
                *insn++ = BPF_LDX_MEM(
                        BPF_SIZE(si->code), si->dst_reg, si->src_reg,
                        bpf_target_off(struct sock_common, skc_daddr,
                                       sizeof_field(struct sock_common,
                                                    skc_daddr),
                                       target_size));
                break;

        case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
#if IS_ENABLED(CONFIG_IPV6)
                off = si->off;
                off -= offsetof(struct bpf_sock, src_ip6[0]);
                *insn++ = BPF_LDX_MEM(
                        BPF_SIZE(si->code), si->dst_reg, si->src_reg,
                        bpf_target_off(
                                struct sock_common,
                                skc_v6_rcv_saddr.s6_addr32[0],
                                sizeof_field(struct sock_common,
                                             skc_v6_rcv_saddr.s6_addr32[0]),
                                target_size) + off);
#else
                (void)off;
                *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
#endif
                break;

        case bpf_ctx_range_till(struct bpf_sock, dst_ip6[0], dst_ip6[3]):
#if IS_ENABLED(CONFIG_IPV6)
                off = si->off;
                off -= offsetof(struct bpf_sock, dst_ip6[0]);
                *insn++ = BPF_LDX_MEM(
                        BPF_SIZE(si->code), si->dst_reg, si->src_reg,
                        bpf_target_off(struct sock_common,
                                       skc_v6_daddr.s6_addr32[0],
                                       sizeof_field(struct sock_common,
                                                    skc_v6_daddr.s6_addr32[0]),
                                       target_size) + off);
#else
                *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
                *target_size = 4;
#endif
                break;

        case offsetof(struct bpf_sock, src_port):
                *insn++ = BPF_LDX_MEM(
                        BPF_FIELD_SIZEOF(struct sock_common, skc_num),
                        si->dst_reg, si->src_reg,
                        bpf_target_off(struct sock_common, skc_num,
                                       sizeof_field(struct sock_common,
                                                    skc_num),
                                       target_size));
                break;

        case offsetof(struct bpf_sock, dst_port):
                *insn++ = BPF_LDX_MEM(
                        BPF_FIELD_SIZEOF(struct sock_common, skc_dport),
                        si->dst_reg, si->src_reg,
                        bpf_target_off(struct sock_common, skc_dport,
                                       sizeof_field(struct sock_common,
                                                    skc_dport),
                                       target_size));
                break;

        case offsetof(struct bpf_sock, state):
                *insn++ = BPF_LDX_MEM(
                        BPF_FIELD_SIZEOF(struct sock_common, skc_state),
                        si->dst_reg, si->src_reg,
                        bpf_target_off(struct sock_common, skc_state,
                                       sizeof_field(struct sock_common,
                                                    skc_state),
                                       target_size));
                break;
        case offsetof(struct bpf_sock, rx_queue_mapping):
#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
                *insn++ = BPF_LDX_MEM(
                        BPF_FIELD_SIZEOF(struct sock, sk_rx_queue_mapping),
                        si->dst_reg, si->src_reg,
                        bpf_target_off(struct sock, sk_rx_queue_mapping,
                                       sizeof_field(struct sock,
                                                    sk_rx_queue_mapping),
                                       target_size));
                *insn++ = BPF_JMP_IMM(BPF_JNE, si->dst_reg, NO_QUEUE_MAPPING,
                                      1);
                *insn++ = BPF_MOV64_IMM(si->dst_reg, -1);
#else
                *insn++ = BPF_MOV64_IMM(si->dst_reg, -1);
                *target_size = 2;
#endif
                break;
        }

        return insn - insn_buf;
}

static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type,
                                         const struct bpf_insn *si,
                                         struct bpf_insn *insn_buf,
                                         struct bpf_prog *prog, u32 *target_size)
{
        struct bpf_insn *insn = insn_buf;

        switch (si->off) {
        case offsetof(struct __sk_buff, ifindex):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_buff, dev));
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      bpf_target_off(struct net_device, ifindex, 4,
                                                     target_size));
                break;
        default:
                return bpf_convert_ctx_access(type, si, insn_buf, prog,
                                              target_size);
        }

        return insn - insn_buf;
}

static u32 xdp_convert_ctx_access(enum bpf_access_type type,
                                  const struct bpf_insn *si,
                                  struct bpf_insn *insn_buf,
                                  struct bpf_prog *prog, u32 *target_size)
{
        struct bpf_insn *insn = insn_buf;

        switch (si->off) {
        case offsetof(struct xdp_md, data):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct xdp_buff, data));
                break;
        case offsetof(struct xdp_md, data_meta):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_meta),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct xdp_buff, data_meta));
                break;
        case offsetof(struct xdp_md, data_end):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_end),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct xdp_buff, data_end));
                break;
        case offsetof(struct xdp_md, ingress_ifindex):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct xdp_buff, rxq));
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_rxq_info, dev),
                                      si->dst_reg, si->dst_reg,
                                      offsetof(struct xdp_rxq_info, dev));
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      offsetof(struct net_device, ifindex));
                break;
        case offsetof(struct xdp_md, rx_queue_index):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct xdp_buff, rxq));
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      offsetof(struct xdp_rxq_info,
                                               queue_index));
                break;
        case offsetof(struct xdp_md, egress_ifindex):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, txq),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct xdp_buff, txq));
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_txq_info, dev),
                                      si->dst_reg, si->dst_reg,
                                      offsetof(struct xdp_txq_info, dev));
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      offsetof(struct net_device, ifindex));
                break;
        }

        return insn - insn_buf;
}

/* SOCK_ADDR_LOAD_NESTED_FIELD() loads Nested Field S.F.NF where S is type of
 * context Structure, F is Field in context structure that contains a pointer
 * to Nested Structure of type NS that has the field NF.
 *
 * SIZE encodes the load size (BPF_B, BPF_H, etc). It's up to caller to make
 * sure that SIZE is not greater than actual size of S.F.NF.
 *
 * If offset OFF is provided, the load happens from that offset relative to
 * offset of NF.
 */
#define SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF)          \
        do {                                                                   \
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), si->dst_reg,     \
                                      si->src_reg, offsetof(S, F));            \
                *insn++ = BPF_LDX_MEM(                                         \
                        SIZE, si->dst_reg, si->dst_reg,                        \
                        bpf_target_off(NS, NF, sizeof_field(NS, NF),           \
                                       target_size)                            \
                                + OFF);                                        \
        } while (0)

#define SOCK_ADDR_LOAD_NESTED_FIELD(S, NS, F, NF)                              \
        SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF,                     \
                                             BPF_FIELD_SIZEOF(NS, NF), 0)

/* SOCK_ADDR_STORE_NESTED_FIELD_OFF() has semantic similar to
 * SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF() but for store operation.
 *
 * In addition it uses Temporary Field TF (member of struct S) as the 3rd
 * "register" since two registers available in convert_ctx_access are not
 * enough: we can't override neither SRC, since it contains value to store, nor
 * DST since it contains pointer to context that may be used by later
 * instructions. But we need a temporary place to save pointer to nested
 * structure whose field we want to store to.
 */
#define SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, SIZE, OFF, TF)          \
        do {                                                                   \
                int tmp_reg = BPF_REG_9;                                       \
                if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg)          \
                        --tmp_reg;                                             \
                if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg)          \
                        --tmp_reg;                                             \
                *insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, tmp_reg,            \
                                      offsetof(S, TF));                        \
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), tmp_reg,         \
                                      si->dst_reg, offsetof(S, F));            \
                *insn++ = BPF_RAW_INSN(SIZE | BPF_MEM | BPF_CLASS(si->code),   \
                                       tmp_reg, si->src_reg,                   \
                        bpf_target_off(NS, NF, sizeof_field(NS, NF),           \
                                       target_size)                            \
                                       + OFF,                                  \
                                       si->imm);                               \
                *insn++ = BPF_LDX_MEM(BPF_DW, tmp_reg, si->dst_reg,            \
                                      offsetof(S, TF));                        \
        } while (0)

#define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF, \
                                                      TF)                      \
        do {                                                                   \
                if (type == BPF_WRITE) {                                       \
                        SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, SIZE,   \
                                                         OFF, TF);             \
                } else {                                                       \
                        SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(                  \
                                S, NS, F, NF, SIZE, OFF);  \
                }                                                              \
        } while (0)

static u32 sock_addr_convert_ctx_access(enum bpf_access_type type,
                                        const struct bpf_insn *si,
                                        struct bpf_insn *insn_buf,
                                        struct bpf_prog *prog, u32 *target_size)
{
        int off, port_size = sizeof_field(struct sockaddr_in6, sin6_port);
        struct bpf_insn *insn = insn_buf;

        switch (si->off) {
        case offsetof(struct bpf_sock_addr, user_family):
                SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
                                            struct sockaddr, uaddr, sa_family);
                break;

        case offsetof(struct bpf_sock_addr, user_ip4):
                SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
                        struct bpf_sock_addr_kern, struct sockaddr_in, uaddr,
                        sin_addr, BPF_SIZE(si->code), 0, tmp_reg);
                break;

        case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
                off = si->off;
                off -= offsetof(struct bpf_sock_addr, user_ip6[0]);
                SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
                        struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr,
                        sin6_addr.s6_addr32[0], BPF_SIZE(si->code), off,
                        tmp_reg);
                break;

        case offsetof(struct bpf_sock_addr, user_port):
                /* To get port we need to know sa_family first and then treat
                 * sockaddr as either sockaddr_in or sockaddr_in6.
                 * Though we can simplify since port field has same offset and
                 * size in both structures.
                 * Here we check this invariant and use just one of the
                 * structures if it's true.
                 */
                BUILD_BUG_ON(offsetof(struct sockaddr_in, sin_port) !=
                             offsetof(struct sockaddr_in6, sin6_port));
                BUILD_BUG_ON(sizeof_field(struct sockaddr_in, sin_port) !=
                             sizeof_field(struct sockaddr_in6, sin6_port));
                /* Account for sin6_port being smaller than user_port. */
                port_size = min(port_size, BPF_LDST_BYTES(si));
                SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
                        struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr,
                        sin6_port, bytes_to_bpf_size(port_size), 0, tmp_reg);
                break;

        case offsetof(struct bpf_sock_addr, family):
                SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
                                            struct sock, sk, sk_family);
                break;

        case offsetof(struct bpf_sock_addr, type):
                SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
                                            struct sock, sk, sk_type);
                break;

        case offsetof(struct bpf_sock_addr, protocol):
                SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
                                            struct sock, sk, sk_protocol);
                break;

        case offsetof(struct bpf_sock_addr, msg_src_ip4):
                /* Treat t_ctx as struct in_addr for msg_src_ip4. */
                SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
                        struct bpf_sock_addr_kern, struct in_addr, t_ctx,
                        s_addr, BPF_SIZE(si->code), 0, tmp_reg);
                break;

        case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
                                msg_src_ip6[3]):
                off = si->off;
                off -= offsetof(struct bpf_sock_addr, msg_src_ip6[0]);
                /* Treat t_ctx as struct in6_addr for msg_src_ip6. */
                SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
                        struct bpf_sock_addr_kern, struct in6_addr, t_ctx,
                        s6_addr32[0], BPF_SIZE(si->code), off, tmp_reg);
                break;
        case offsetof(struct bpf_sock_addr, sk):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_addr_kern, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sock_addr_kern, sk));
                break;
        }

        return insn - insn_buf;
}

static u32 sock_ops_convert_ctx_access(enum bpf_access_type type,
                                       const struct bpf_insn *si,
                                       struct bpf_insn *insn_buf,
                                       struct bpf_prog *prog,
                                       u32 *target_size)
{
        struct bpf_insn *insn = insn_buf;
        int off;

/* Helper macro for adding read access to tcp_sock or sock fields. */
#define SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ)                         \
        do {                                                                  \
                int fullsock_reg = si->dst_reg, reg = BPF_REG_9, jmp = 2;     \
                BUILD_BUG_ON(sizeof_field(OBJ, OBJ_FIELD) >                   \
                             sizeof_field(struct bpf_sock_ops, BPF_FIELD));   \
                if (si->dst_reg == reg || si->src_reg == reg)                 \
                        reg--;                                                \
                if (si->dst_reg == reg || si->src_reg == reg)                 \
                        reg--;                                                \
                if (si->dst_reg == si->src_reg) {                             \
                        *insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg,       \
                                          offsetof(struct bpf_sock_ops_kern,  \
                                          temp));                             \
                        fullsock_reg = reg;                                   \
                        jmp += 2;                                             \
                }                                                             \
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(                       \
                                                struct bpf_sock_ops_kern,     \
                                                is_locked_tcp_sock),          \
                                      fullsock_reg, si->src_reg,              \
                                      offsetof(struct bpf_sock_ops_kern,      \
                                               is_locked_tcp_sock));          \
                *insn++ = BPF_JMP_IMM(BPF_JEQ, fullsock_reg, 0, jmp);         \
                if (si->dst_reg == si->src_reg)                               \
                        *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg,       \
                                      offsetof(struct bpf_sock_ops_kern,      \
                                      temp));                                 \
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(                       \
                                                struct bpf_sock_ops_kern, sk),\
                                      si->dst_reg, si->src_reg,               \
                                      offsetof(struct bpf_sock_ops_kern, sk));\
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(OBJ,                   \
                                                       OBJ_FIELD),            \
                                      si->dst_reg, si->dst_reg,               \
                                      offsetof(OBJ, OBJ_FIELD));              \
                if (si->dst_reg == si->src_reg) {                             \
                        *insn++ = BPF_JMP_A(2);                               \
                        *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg,       \
                                      offsetof(struct bpf_sock_ops_kern,      \
                                      temp));                                 \
                        *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);              \
                }                                                             \
        } while (0)

#define SOCK_OPS_GET_SK()                                                             \
        do {                                                                  \
                int fullsock_reg = si->dst_reg, reg = BPF_REG_9, jmp = 1;     \
                if (si->dst_reg == reg || si->src_reg == reg)                 \
                        reg--;                                                \
                if (si->dst_reg == reg || si->src_reg == reg)                 \
                        reg--;                                                \
                if (si->dst_reg == si->src_reg) {                             \
                        *insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg,       \
                                          offsetof(struct bpf_sock_ops_kern,  \
                                          temp));                             \
                        fullsock_reg = reg;                                   \
                        jmp += 2;                                             \
                }                                                             \
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(                       \
                                                struct bpf_sock_ops_kern,     \
                                                is_fullsock),                 \
                                      fullsock_reg, si->src_reg,              \
                                      offsetof(struct bpf_sock_ops_kern,      \
                                               is_fullsock));                 \
                *insn++ = BPF_JMP_IMM(BPF_JEQ, fullsock_reg, 0, jmp);         \
                if (si->dst_reg == si->src_reg)                               \
                        *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg,       \
                                      offsetof(struct bpf_sock_ops_kern,      \
                                      temp));                                 \
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(                       \
                                                struct bpf_sock_ops_kern, sk),\
                                      si->dst_reg, si->src_reg,               \
                                      offsetof(struct bpf_sock_ops_kern, sk));\
                if (si->dst_reg == si->src_reg) {                             \
                        *insn++ = BPF_JMP_A(2);                               \
                        *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg,       \
                                      offsetof(struct bpf_sock_ops_kern,      \
                                      temp));                                 \
                        *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);              \
                }                                                             \
        } while (0)

#define SOCK_OPS_GET_TCP_SOCK_FIELD(FIELD) \
                SOCK_OPS_GET_FIELD(FIELD, FIELD, struct tcp_sock)

/* Helper macro for adding write access to tcp_sock or sock fields.
 * The macro is called with two registers, dst_reg which contains a pointer
 * to ctx (context) and src_reg which contains the value that should be
 * stored. However, we need an additional register since we cannot overwrite
 * dst_reg because it may be used later in the program.
 * Instead we "borrow" one of the other register. We first save its value
 * into a new (temp) field in bpf_sock_ops_kern, use it, and then restore
 * it at the end of the macro.
 */
#define SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ)                         \
        do {                                                                  \
                int reg = BPF_REG_9;                                          \
                BUILD_BUG_ON(sizeof_field(OBJ, OBJ_FIELD) >                   \
                             sizeof_field(struct bpf_sock_ops, BPF_FIELD));   \
                if (si->dst_reg == reg || si->src_reg == reg)                 \
                        reg--;                                                \
                if (si->dst_reg == reg || si->src_reg == reg)                 \
                        reg--;                                                \
                *insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, reg,               \
                                      offsetof(struct bpf_sock_ops_kern,      \
                                               temp));                        \
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(                       \
                                                struct bpf_sock_ops_kern,     \
                                                is_locked_tcp_sock),          \
                                      reg, si->dst_reg,                       \
                                      offsetof(struct bpf_sock_ops_kern,      \
                                               is_locked_tcp_sock));          \
                *insn++ = BPF_JMP_IMM(BPF_JEQ, reg, 0, 2);                    \
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(                       \
                                                struct bpf_sock_ops_kern, sk),\
                                      reg, si->dst_reg,                       \
                                      offsetof(struct bpf_sock_ops_kern, sk));\
                *insn++ = BPF_RAW_INSN(BPF_FIELD_SIZEOF(OBJ, OBJ_FIELD) |     \
                                       BPF_MEM | BPF_CLASS(si->code),         \
                                       reg, si->src_reg,                      \
                                       offsetof(OBJ, OBJ_FIELD),              \
                                       si->imm);                              \
                *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->dst_reg,               \
                                      offsetof(struct bpf_sock_ops_kern,      \
                                               temp));                        \
        } while (0)

#define SOCK_OPS_GET_OR_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ, TYPE)            \
        do {                                                                  \
                if (TYPE == BPF_WRITE)                                        \
                        SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ);        \
                else                                                          \
                        SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ);        \
        } while (0)

        switch (si->off) {
        case offsetof(struct bpf_sock_ops, op):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
                                                       op),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sock_ops_kern, op));
                break;

        case offsetof(struct bpf_sock_ops, replylong[0]) ...
             offsetof(struct bpf_sock_ops, replylong[3]):
                BUILD_BUG_ON(sizeof_field(struct bpf_sock_ops, reply) !=
                             sizeof_field(struct bpf_sock_ops_kern, reply));
                BUILD_BUG_ON(sizeof_field(struct bpf_sock_ops, replylong) !=
                             sizeof_field(struct bpf_sock_ops_kern, replylong));
                off = si->off;
                off -= offsetof(struct bpf_sock_ops, replylong[0]);
                off += offsetof(struct bpf_sock_ops_kern, replylong[0]);
                if (type == BPF_WRITE)
                        *insn++ = BPF_EMIT_STORE(BPF_W, si, off);
                else
                        *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
                                              off);
                break;

        case offsetof(struct bpf_sock_ops, family):
                BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
                                              struct bpf_sock_ops_kern, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sock_ops_kern, sk));
                *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
                                      offsetof(struct sock_common, skc_family));
                break;

        case offsetof(struct bpf_sock_ops, remote_ip4):
                BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
                                                struct bpf_sock_ops_kern, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sock_ops_kern, sk));
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      offsetof(struct sock_common, skc_daddr));
                break;

        case offsetof(struct bpf_sock_ops, local_ip4):
                BUILD_BUG_ON(sizeof_field(struct sock_common,
                                          skc_rcv_saddr) != 4);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
                                              struct bpf_sock_ops_kern, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sock_ops_kern, sk));
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      offsetof(struct sock_common,
                                               skc_rcv_saddr));
                break;

        case offsetof(struct bpf_sock_ops, remote_ip6[0]) ...
             offsetof(struct bpf_sock_ops, remote_ip6[3]):
#if IS_ENABLED(CONFIG_IPV6)
                BUILD_BUG_ON(sizeof_field(struct sock_common,
                                          skc_v6_daddr.s6_addr32[0]) != 4);

                off = si->off;
                off -= offsetof(struct bpf_sock_ops, remote_ip6[0]);
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
                                                struct bpf_sock_ops_kern, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sock_ops_kern, sk));
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      offsetof(struct sock_common,
                                               skc_v6_daddr.s6_addr32[0]) +
                                      off);
#else
                *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
#endif
                break;

        case offsetof(struct bpf_sock_ops, local_ip6[0]) ...
             offsetof(struct bpf_sock_ops, local_ip6[3]):
#if IS_ENABLED(CONFIG_IPV6)
                BUILD_BUG_ON(sizeof_field(struct sock_common,
                                          skc_v6_rcv_saddr.s6_addr32[0]) != 4);

                off = si->off;
                off -= offsetof(struct bpf_sock_ops, local_ip6[0]);
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
                                                struct bpf_sock_ops_kern, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sock_ops_kern, sk));
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      offsetof(struct sock_common,
                                               skc_v6_rcv_saddr.s6_addr32[0]) +
                                      off);
#else
                *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
#endif
                break;

        case offsetof(struct bpf_sock_ops, remote_port):
                BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
                                                struct bpf_sock_ops_kern, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sock_ops_kern, sk));
                *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
                                      offsetof(struct sock_common, skc_dport));
#ifndef __BIG_ENDIAN_BITFIELD
                *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
#endif
                break;

        case offsetof(struct bpf_sock_ops, local_port):
                BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
                                                struct bpf_sock_ops_kern, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sock_ops_kern, sk));
                *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
                                      offsetof(struct sock_common, skc_num));
                break;

        case offsetof(struct bpf_sock_ops, is_fullsock):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
                                                struct bpf_sock_ops_kern,
                                                is_fullsock),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sock_ops_kern,
                                               is_fullsock));
                break;

        case offsetof(struct bpf_sock_ops, state):
                BUILD_BUG_ON(sizeof_field(struct sock_common, skc_state) != 1);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
                                                struct bpf_sock_ops_kern, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sock_ops_kern, sk));
                *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->dst_reg,
                                      offsetof(struct sock_common, skc_state));
                break;

        case offsetof(struct bpf_sock_ops, rtt_min):
                BUILD_BUG_ON(sizeof_field(struct tcp_sock, rtt_min) !=
                             sizeof(struct minmax));
                BUILD_BUG_ON(sizeof(struct minmax) <
                             sizeof(struct minmax_sample));

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
                                                struct bpf_sock_ops_kern, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sock_ops_kern, sk));
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      offsetof(struct tcp_sock, rtt_min) +
                                      sizeof_field(struct minmax_sample, t));
                break;

        case offsetof(struct bpf_sock_ops, bpf_sock_ops_cb_flags):
                SOCK_OPS_GET_FIELD(bpf_sock_ops_cb_flags, bpf_sock_ops_cb_flags,
                                   struct tcp_sock);
                break;

        case offsetof(struct bpf_sock_ops, sk_txhash):
                SOCK_OPS_GET_OR_SET_FIELD(sk_txhash, sk_txhash,
                                          struct sock, type);
                break;
        case offsetof(struct bpf_sock_ops, snd_cwnd):
                SOCK_OPS_GET_TCP_SOCK_FIELD(snd_cwnd);
                break;
        case offsetof(struct bpf_sock_ops, srtt_us):
                SOCK_OPS_GET_TCP_SOCK_FIELD(srtt_us);
                break;
        case offsetof(struct bpf_sock_ops, snd_ssthresh):
                SOCK_OPS_GET_TCP_SOCK_FIELD(snd_ssthresh);
                break;
        case offsetof(struct bpf_sock_ops, rcv_nxt):
                SOCK_OPS_GET_TCP_SOCK_FIELD(rcv_nxt);
                break;
        case offsetof(struct bpf_sock_ops, snd_nxt):
                SOCK_OPS_GET_TCP_SOCK_FIELD(snd_nxt);
                break;
        case offsetof(struct bpf_sock_ops, snd_una):
                SOCK_OPS_GET_TCP_SOCK_FIELD(snd_una);
                break;
        case offsetof(struct bpf_sock_ops, mss_cache):
                SOCK_OPS_GET_TCP_SOCK_FIELD(mss_cache);
                break;
        case offsetof(struct bpf_sock_ops, ecn_flags):
                SOCK_OPS_GET_TCP_SOCK_FIELD(ecn_flags);
                break;
        case offsetof(struct bpf_sock_ops, rate_delivered):
                SOCK_OPS_GET_TCP_SOCK_FIELD(rate_delivered);
                break;
        case offsetof(struct bpf_sock_ops, rate_interval_us):
                SOCK_OPS_GET_TCP_SOCK_FIELD(rate_interval_us);
                break;
        case offsetof(struct bpf_sock_ops, packets_out):
                SOCK_OPS_GET_TCP_SOCK_FIELD(packets_out);
                break;
        case offsetof(struct bpf_sock_ops, retrans_out):
                SOCK_OPS_GET_TCP_SOCK_FIELD(retrans_out);
                break;
        case offsetof(struct bpf_sock_ops, total_retrans):
                SOCK_OPS_GET_TCP_SOCK_FIELD(total_retrans);
                break;
        case offsetof(struct bpf_sock_ops, segs_in):
                SOCK_OPS_GET_TCP_SOCK_FIELD(segs_in);
                break;
        case offsetof(struct bpf_sock_ops, data_segs_in):
                SOCK_OPS_GET_TCP_SOCK_FIELD(data_segs_in);
                break;
        case offsetof(struct bpf_sock_ops, segs_out):
                SOCK_OPS_GET_TCP_SOCK_FIELD(segs_out);
                break;
        case offsetof(struct bpf_sock_ops, data_segs_out):
                SOCK_OPS_GET_TCP_SOCK_FIELD(data_segs_out);
                break;
        case offsetof(struct bpf_sock_ops, lost_out):
                SOCK_OPS_GET_TCP_SOCK_FIELD(lost_out);
                break;
        case offsetof(struct bpf_sock_ops, sacked_out):
                SOCK_OPS_GET_TCP_SOCK_FIELD(sacked_out);
                break;
        case offsetof(struct bpf_sock_ops, bytes_received):
                SOCK_OPS_GET_TCP_SOCK_FIELD(bytes_received);
                break;
        case offsetof(struct bpf_sock_ops, bytes_acked):
                SOCK_OPS_GET_TCP_SOCK_FIELD(bytes_acked);
                break;
        case offsetof(struct bpf_sock_ops, sk):
                SOCK_OPS_GET_SK();
                break;
        case offsetof(struct bpf_sock_ops, skb_data_end):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
                                                       skb_data_end),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sock_ops_kern,
                                               skb_data_end));
                break;
        case offsetof(struct bpf_sock_ops, skb_data):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
                                                       skb),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sock_ops_kern,
                                               skb));
                *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
                                      si->dst_reg, si->dst_reg,
                                      offsetof(struct sk_buff, data));
                break;
        case offsetof(struct bpf_sock_ops, skb_len):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
                                                       skb),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sock_ops_kern,
                                               skb));
                *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, len),
                                      si->dst_reg, si->dst_reg,
                                      offsetof(struct sk_buff, len));
                break;
        case offsetof(struct bpf_sock_ops, skb_tcp_flags):
                off = offsetof(struct sk_buff, cb);
                off += offsetof(struct tcp_skb_cb, tcp_flags);
                *target_size = sizeof_field(struct tcp_skb_cb, tcp_flags);
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
                                                       skb),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sock_ops_kern,
                                               skb));
                *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct tcp_skb_cb,
                                                       tcp_flags),
                                      si->dst_reg, si->dst_reg, off);
                break;
        case offsetof(struct bpf_sock_ops, skb_hwtstamp): {
                struct bpf_insn *jmp_on_null_skb;

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
                                                       skb),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sock_ops_kern,
                                               skb));
                /* Reserve one insn to test skb == NULL */
                jmp_on_null_skb = insn++;
                insn = bpf_convert_shinfo_access(si->dst_reg, si->dst_reg, insn);
                *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
                                      bpf_target_off(struct skb_shared_info,
                                                     hwtstamps, 8,
                                                     target_size));
                *jmp_on_null_skb = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0,
                                               insn - jmp_on_null_skb - 1);
                break;
        }
        }
        return insn - insn_buf;
}

/* data_end = skb->data + skb_headlen() */
static struct bpf_insn *bpf_convert_data_end_access(const struct bpf_insn *si,
                                                    struct bpf_insn *insn)
{
        int reg;
        int temp_reg_off = offsetof(struct sk_buff, cb) +
                           offsetof(struct sk_skb_cb, temp_reg);

        if (si->src_reg == si->dst_reg) {
                /* We need an extra register, choose and save a register. */
                reg = BPF_REG_9;
                if (si->src_reg == reg || si->dst_reg == reg)
                        reg--;
                if (si->src_reg == reg || si->dst_reg == reg)
                        reg--;
                *insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg, temp_reg_off);
        } else {
                reg = si->dst_reg;
        }

        /* reg = skb->data */
        *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
                              reg, si->src_reg,
                              offsetof(struct sk_buff, data));
        /* AX = skb->len */
        *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, len),
                              BPF_REG_AX, si->src_reg,
                              offsetof(struct sk_buff, len));
        /* reg = skb->data + skb->len */
        *insn++ = BPF_ALU64_REG(BPF_ADD, reg, BPF_REG_AX);
        /* AX = skb->data_len */
        *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data_len),
                              BPF_REG_AX, si->src_reg,
                              offsetof(struct sk_buff, data_len));

        /* reg = skb->data + skb->len - skb->data_len */
        *insn++ = BPF_ALU64_REG(BPF_SUB, reg, BPF_REG_AX);

        if (si->src_reg == si->dst_reg) {
                /* Restore the saved register */
                *insn++ = BPF_MOV64_REG(BPF_REG_AX, si->src_reg);
                *insn++ = BPF_MOV64_REG(si->dst_reg, reg);
                *insn++ = BPF_LDX_MEM(BPF_DW, reg, BPF_REG_AX, temp_reg_off);
        }

        return insn;
}

static u32 sk_skb_convert_ctx_access(enum bpf_access_type type,
                                     const struct bpf_insn *si,
                                     struct bpf_insn *insn_buf,
                                     struct bpf_prog *prog, u32 *target_size)
{
        struct bpf_insn *insn = insn_buf;
        int off;

        switch (si->off) {
        case offsetof(struct __sk_buff, data_end):
                insn = bpf_convert_data_end_access(si, insn);
                break;
        case offsetof(struct __sk_buff, cb[0]) ...
             offsetofend(struct __sk_buff, cb[4]) - 1:
                BUILD_BUG_ON(sizeof_field(struct sk_skb_cb, data) < 20);
                BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
                              offsetof(struct sk_skb_cb, data)) %
                             sizeof(__u64));

                prog->cb_access = 1;
                off  = si->off;
                off -= offsetof(struct __sk_buff, cb[0]);
                off += offsetof(struct sk_buff, cb);
                off += offsetof(struct sk_skb_cb, data);
                if (type == BPF_WRITE)
                        *insn++ = BPF_EMIT_STORE(BPF_SIZE(si->code), si, off);
                else
                        *insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
                                              si->src_reg, off);
                break;


        default:
                return bpf_convert_ctx_access(type, si, insn_buf, prog,
                                              target_size);
        }

        return insn - insn_buf;
}

static u32 sk_msg_convert_ctx_access(enum bpf_access_type type,
                                     const struct bpf_insn *si,
                                     struct bpf_insn *insn_buf,
                                     struct bpf_prog *prog, u32 *target_size)
{
        struct bpf_insn *insn = insn_buf;
#if IS_ENABLED(CONFIG_IPV6)
        int off;
#endif

        /* convert ctx uses the fact sg element is first in struct */
        BUILD_BUG_ON(offsetof(struct sk_msg, sg) != 0);

        switch (si->off) {
        case offsetof(struct sk_msg_md, data):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, data),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_msg, data));
                break;
        case offsetof(struct sk_msg_md, data_end):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, data_end),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_msg, data_end));
                break;
        case offsetof(struct sk_msg_md, family):
                BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
                                              struct sk_msg, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_msg, sk));
                *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
                                      offsetof(struct sock_common, skc_family));
                break;

        case offsetof(struct sk_msg_md, remote_ip4):
                BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
                                                struct sk_msg, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_msg, sk));
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      offsetof(struct sock_common, skc_daddr));
                break;

        case offsetof(struct sk_msg_md, local_ip4):
                BUILD_BUG_ON(sizeof_field(struct sock_common,
                                          skc_rcv_saddr) != 4);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
                                              struct sk_msg, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_msg, sk));
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      offsetof(struct sock_common,
                                               skc_rcv_saddr));
                break;

        case offsetof(struct sk_msg_md, remote_ip6[0]) ...
             offsetof(struct sk_msg_md, remote_ip6[3]):
#if IS_ENABLED(CONFIG_IPV6)
                BUILD_BUG_ON(sizeof_field(struct sock_common,
                                          skc_v6_daddr.s6_addr32[0]) != 4);

                off = si->off;
                off -= offsetof(struct sk_msg_md, remote_ip6[0]);
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
                                                struct sk_msg, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_msg, sk));
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      offsetof(struct sock_common,
                                               skc_v6_daddr.s6_addr32[0]) +
                                      off);
#else
                *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
#endif
                break;

        case offsetof(struct sk_msg_md, local_ip6[0]) ...
             offsetof(struct sk_msg_md, local_ip6[3]):
#if IS_ENABLED(CONFIG_IPV6)
                BUILD_BUG_ON(sizeof_field(struct sock_common,
                                          skc_v6_rcv_saddr.s6_addr32[0]) != 4);

                off = si->off;
                off -= offsetof(struct sk_msg_md, local_ip6[0]);
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
                                                struct sk_msg, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_msg, sk));
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
                                      offsetof(struct sock_common,
                                               skc_v6_rcv_saddr.s6_addr32[0]) +
                                      off);
#else
                *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
#endif
                break;

        case offsetof(struct sk_msg_md, remote_port):
                BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
                                                struct sk_msg, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_msg, sk));
                *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
                                      offsetof(struct sock_common, skc_dport));
#ifndef __BIG_ENDIAN_BITFIELD
                *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
#endif
                break;

        case offsetof(struct sk_msg_md, local_port):
                BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);

                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
                                                struct sk_msg, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_msg, sk));
                *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
                                      offsetof(struct sock_common, skc_num));
                break;

        case offsetof(struct sk_msg_md, size):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg_sg, size),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_msg_sg, size));
                break;

        case offsetof(struct sk_msg_md, sk):
                *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, sk),
                                      si->dst_reg, si->src_reg,
                                      offsetof(struct sk_msg, sk));
                break;
        }

        return insn - insn_buf;
}

const struct bpf_verifier_ops sk_filter_verifier_ops = {
        .get_func_proto         = sk_filter_func_proto,
        .is_valid_access        = sk_filter_is_valid_access,
        .convert_ctx_access     = bpf_convert_ctx_access,
        .gen_ld_abs             = bpf_gen_ld_abs,
};

const struct bpf_prog_ops sk_filter_prog_ops = {
        .test_run               = bpf_prog_test_run_skb,
};

const struct bpf_verifier_ops tc_cls_act_verifier_ops = {
        .get_func_proto         = tc_cls_act_func_proto,
        .is_valid_access        = tc_cls_act_is_valid_access,
        .convert_ctx_access     = tc_cls_act_convert_ctx_access,
        .gen_prologue           = tc_cls_act_prologue,
        .gen_ld_abs             = bpf_gen_ld_abs,
        .btf_struct_access      = tc_cls_act_btf_struct_access,
};

const struct bpf_prog_ops tc_cls_act_prog_ops = {
        .test_run               = bpf_prog_test_run_skb,
};

const struct bpf_verifier_ops xdp_verifier_ops = {
        .get_func_proto         = xdp_func_proto,
        .is_valid_access        = xdp_is_valid_access,
        .convert_ctx_access     = xdp_convert_ctx_access,
        .gen_prologue           = bpf_noop_prologue,
        .btf_struct_access      = xdp_btf_struct_access,
};

const struct bpf_prog_ops xdp_prog_ops = {
        .test_run               = bpf_prog_test_run_xdp,
};

const struct bpf_verifier_ops cg_skb_verifier_ops = {
        .get_func_proto         = cg_skb_func_proto,
        .is_valid_access        = cg_skb_is_valid_access,
        .convert_ctx_access     = bpf_convert_ctx_access,
};

const struct bpf_prog_ops cg_skb_prog_ops = {
        .test_run               = bpf_prog_test_run_skb,
};

const struct bpf_verifier_ops lwt_in_verifier_ops = {
        .get_func_proto         = lwt_in_func_proto,
        .is_valid_access        = lwt_is_valid_access,
        .convert_ctx_access     = bpf_convert_ctx_access,
};

const struct bpf_prog_ops lwt_in_prog_ops = {
        .test_run               = bpf_prog_test_run_skb,
};

const struct bpf_verifier_ops lwt_out_verifier_ops = {
        .get_func_proto         = lwt_out_func_proto,
        .is_valid_access        = lwt_is_valid_access,
        .convert_ctx_access     = bpf_convert_ctx_access,
};

const struct bpf_prog_ops lwt_out_prog_ops = {
        .test_run               = bpf_prog_test_run_skb,
};

const struct bpf_verifier_ops lwt_xmit_verifier_ops = {
        .get_func_proto         = lwt_xmit_func_proto,
        .is_valid_access        = lwt_is_valid_access,
        .convert_ctx_access     = bpf_convert_ctx_access,
        .gen_prologue           = tc_cls_act_prologue,
};

const struct bpf_prog_ops lwt_xmit_prog_ops = {
        .test_run               = bpf_prog_test_run_skb,
};

const struct bpf_verifier_ops lwt_seg6local_verifier_ops = {
        .get_func_proto         = lwt_seg6local_func_proto,
        .is_valid_access        = lwt_is_valid_access,
        .convert_ctx_access     = bpf_convert_ctx_access,
};

const struct bpf_prog_ops lwt_seg6local_prog_ops = {
};

const struct bpf_verifier_ops cg_sock_verifier_ops = {
        .get_func_proto         = sock_filter_func_proto,
        .is_valid_access        = sock_filter_is_valid_access,
        .convert_ctx_access     = bpf_sock_convert_ctx_access,
};

const struct bpf_prog_ops cg_sock_prog_ops = {
};

const struct bpf_verifier_ops cg_sock_addr_verifier_ops = {
        .get_func_proto         = sock_addr_func_proto,
        .is_valid_access        = sock_addr_is_valid_access,
        .convert_ctx_access     = sock_addr_convert_ctx_access,
};

const struct bpf_prog_ops cg_sock_addr_prog_ops = {
};

const struct bpf_verifier_ops sock_ops_verifier_ops = {
        .get_func_proto         = sock_ops_func_proto,
        .is_valid_access        = sock_ops_is_valid_access,
        .convert_ctx_access     = sock_ops_convert_ctx_access,
};

const struct bpf_prog_ops sock_ops_prog_ops = {
};

const struct bpf_verifier_ops sk_skb_verifier_ops = {
        .get_func_proto         = sk_skb_func_proto,
        .is_valid_access        = sk_skb_is_valid_access,
        .convert_ctx_access     = sk_skb_convert_ctx_access,
        .gen_prologue           = sk_skb_prologue,
};

const struct bpf_prog_ops sk_skb_prog_ops = {
};

const struct bpf_verifier_ops sk_msg_verifier_ops = {
        .get_func_proto         = sk_msg_func_proto,
        .is_valid_access        = sk_msg_is_valid_access,
        .convert_ctx_access     = sk_msg_convert_ctx_access,
        .gen_prologue           = bpf_noop_prologue,
};

const struct bpf_prog_ops sk_msg_prog_ops = {
};

const struct bpf_verifier_ops flow_dissector_verifier_ops = {
        .get_func_proto         = flow_dissector_func_proto,
        .is_valid_access        = flow_dissector_is_valid_access,
        .convert_ctx_access     = flow_dissector_convert_ctx_access,
};

const struct bpf_prog_ops flow_dissector_prog_ops = {
        .test_run               = bpf_prog_test_run_flow_dissector,
};

int sk_detach_filter(struct sock *sk)
{
        int ret = -ENOENT;
        struct sk_filter *filter;

        if (sock_flag(sk, SOCK_FILTER_LOCKED))
                return -EPERM;

        filter = rcu_dereference_protected(sk->sk_filter,
                                           lockdep_sock_is_held(sk));
        if (filter) {
                RCU_INIT_POINTER(sk->sk_filter, NULL);
                sk_filter_uncharge(sk, filter);
                ret = 0;
        }

        return ret;
}
EXPORT_SYMBOL_GPL(sk_detach_filter);

int sk_get_filter(struct sock *sk, sockptr_t optval, unsigned int len)
{
        struct sock_fprog_kern *fprog;
        struct sk_filter *filter;
        int ret = 0;

        sockopt_lock_sock(sk);
        filter = rcu_dereference_protected(sk->sk_filter,
                                           lockdep_sock_is_held(sk));
        if (!filter)
                goto out;

        /* We're copying the filter that has been originally attached,
         * so no conversion/decode needed anymore. eBPF programs that
         * have no original program cannot be dumped through this.
         */
        ret = -EACCES;
        fprog = filter->prog->orig_prog;
        if (!fprog)
                goto out;

        ret = fprog->len;
        if (!len)
                /* User space only enquires number of filter blocks. */
                goto out;

        ret = -EINVAL;
        if (len < fprog->len)
                goto out;

        ret = -EFAULT;
        if (copy_to_sockptr(optval, fprog->filter, bpf_classic_proglen(fprog)))
                goto out;

        /* Instead of bytes, the API requests to return the number
         * of filter blocks.
         */
        ret = fprog->len;
out:
        sockopt_release_sock(sk);
        return ret;
}

#ifdef CONFIG_INET
static void bpf_init_reuseport_kern(struct sk_reuseport_kern *reuse_kern,
                                    struct sock_reuseport *reuse,
                                    struct sock *sk, struct sk_buff *skb,
                                    struct sock *migrating_sk,
                                    u32 hash)
{
        reuse_kern->skb = skb;
        reuse_kern->sk = sk;
        reuse_kern->selected_sk = NULL;
        reuse_kern->migrating_sk = migrating_sk;
        reuse_kern->data_end = skb->data + skb_headlen(skb);
        reuse_kern->hash = hash;
        reuse_kern->reuseport_id = reuse->reuseport_id;
        reuse_kern->bind_inany = reuse->bind_inany;
}

struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
                                  struct bpf_prog *prog, struct sk_buff *skb,
                                  struct sock *migrating_sk,
                                  u32 hash)
{
        struct sk_reuseport_kern reuse_kern;
        enum sk_action action;

        bpf_init_reuseport_kern(&reuse_kern, reuse, sk, skb, migrating_sk, hash);
        action = bpf_prog_run(prog, &reuse_kern);

        if (action == SK_PASS)
                return reuse_kern.selected_sk;
        else
                return ERR_PTR(-ECONNREFUSED);
}

BPF_CALL_4(sk_select_reuseport, struct sk_reuseport_kern *, reuse_kern,
           struct bpf_map *, map, void *, key, u32, flags)
{
        bool is_sockarray = map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY;
        struct sock_reuseport *reuse;
        struct sock *selected_sk;
        int err;

        selected_sk = map->ops->map_lookup_elem(map, key);
        if (!selected_sk)
                return -ENOENT;

        reuse = rcu_dereference(selected_sk->sk_reuseport_cb);
        if (!reuse) {
                /* reuseport_array has only sk with non NULL sk_reuseport_cb.
                 * The only (!reuse) case here is - the sk has already been
                 * unhashed (e.g. by close()), so treat it as -ENOENT.
                 *
                 * Other maps (e.g. sock_map) do not provide this guarantee and
                 * the sk may never be in the reuseport group to begin with.
                 */
                err = is_sockarray ? -ENOENT : -EINVAL;
                goto error;
        }

        if (unlikely(reuse->reuseport_id != reuse_kern->reuseport_id)) {
                struct sock *sk = reuse_kern->sk;

                if (sk->sk_protocol != selected_sk->sk_protocol) {
                        err = -EPROTOTYPE;
                } else if (sk->sk_family != selected_sk->sk_family) {
                        err = -EAFNOSUPPORT;
                } else {
                        /* Catch all. Likely bound to a different sockaddr. */
                        err = -EBADFD;
                }
                goto error;
        }

        reuse_kern->selected_sk = selected_sk;

        return 0;
error:
        /* Lookup in sock_map can return TCP ESTABLISHED sockets. */
        if (sk_is_refcounted(selected_sk))
                sock_put(selected_sk);

        return err;
}

static const struct bpf_func_proto sk_select_reuseport_proto = {
        .func           = sk_select_reuseport,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_CONST_MAP_PTR,
        .arg3_type      = ARG_PTR_TO_MAP_KEY,
        .arg4_type      = ARG_ANYTHING,
};

BPF_CALL_4(sk_reuseport_load_bytes,
           const struct sk_reuseport_kern *, reuse_kern, u32, offset,
           void *, to, u32, len)
{
        return ____bpf_skb_load_bytes(reuse_kern->skb, offset, to, len);
}

static const struct bpf_func_proto sk_reuseport_load_bytes_proto = {
        .func           = sk_reuseport_load_bytes,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_PTR_TO_UNINIT_MEM,
        .arg4_type      = ARG_CONST_SIZE,
};

BPF_CALL_5(sk_reuseport_load_bytes_relative,
           const struct sk_reuseport_kern *, reuse_kern, u32, offset,
           void *, to, u32, len, u32, start_header)
{
        return ____bpf_skb_load_bytes_relative(reuse_kern->skb, offset, to,
                                               len, start_header);
}

static const struct bpf_func_proto sk_reuseport_load_bytes_relative_proto = {
        .func           = sk_reuseport_load_bytes_relative,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_ANYTHING,
        .arg3_type      = ARG_PTR_TO_UNINIT_MEM,
        .arg4_type      = ARG_CONST_SIZE,
        .arg5_type      = ARG_ANYTHING,
};

static const struct bpf_func_proto *
sk_reuseport_func_proto(enum bpf_func_id func_id,
                        const struct bpf_prog *prog)
{
        switch (func_id) {
        case BPF_FUNC_sk_select_reuseport:
                return &sk_select_reuseport_proto;
        case BPF_FUNC_skb_load_bytes:
                return &sk_reuseport_load_bytes_proto;
        case BPF_FUNC_skb_load_bytes_relative:
                return &sk_reuseport_load_bytes_relative_proto;
        case BPF_FUNC_get_socket_cookie:
                return &bpf_get_socket_ptr_cookie_proto;
        case BPF_FUNC_ktime_get_coarse_ns:
                return &bpf_ktime_get_coarse_ns_proto;
        default:
                return bpf_base_func_proto(func_id, prog);
        }
}

static bool
sk_reuseport_is_valid_access(int off, int size,
                             enum bpf_access_type type,
                             const struct bpf_prog *prog,
                             struct bpf_insn_access_aux *info)
{
        const u32 size_default = sizeof(__u32);

        if (off < 0 || off >= sizeof(struct sk_reuseport_md) ||
            off % size || type != BPF_READ)
                return false;

        switch (off) {
        case offsetof(struct sk_reuseport_md, data):
                info->reg_type = PTR_TO_PACKET;
                return size == sizeof(__u64);

        case offsetof(struct sk_reuseport_md, data_end):
                info->reg_type = PTR_TO_PACKET_END;
                return size == sizeof(__u64);

        case offsetof(struct sk_reuseport_md, hash):
                return size == size_default;

        case offsetof(struct sk_reuseport_md, sk):
                info->reg_type = PTR_TO_SOCKET;
                return size == sizeof(__u64);

        case offsetof(struct sk_reuseport_md, migrating_sk):
                info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL;
                return size == sizeof(__u64);

        /* Fields that allow narrowing */
        case bpf_ctx_range(struct sk_reuseport_md, eth_protocol):
                if (size < sizeof_field(struct sk_buff, protocol))
                        return false;
                fallthrough;
        case bpf_ctx_range(struct sk_reuseport_md, ip_protocol):
        case bpf_ctx_range(struct sk_reuseport_md, bind_inany):
        case bpf_ctx_range(struct sk_reuseport_md, len):
                bpf_ctx_record_field_size(info, size_default);
                return bpf_ctx_narrow_access_ok(off, size, size_default);

        default:
                return false;
        }
}

#define SK_REUSEPORT_LOAD_FIELD(F) ({                                   \
        *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_reuseport_kern, F), \
                              si->dst_reg, si->src_reg,                 \
                              bpf_target_off(struct sk_reuseport_kern, F, \
                                             sizeof_field(struct sk_reuseport_kern, F), \
                                             target_size));             \
        })

#define SK_REUSEPORT_LOAD_SKB_FIELD(SKB_FIELD)                          \
        SOCK_ADDR_LOAD_NESTED_FIELD(struct sk_reuseport_kern,           \
                                    struct sk_buff,                     \
                                    skb,                                \
                                    SKB_FIELD)

#define SK_REUSEPORT_LOAD_SK_FIELD(SK_FIELD)                            \
        SOCK_ADDR_LOAD_NESTED_FIELD(struct sk_reuseport_kern,           \
                                    struct sock,                        \
                                    sk,                                 \
                                    SK_FIELD)

static u32 sk_reuseport_convert_ctx_access(enum bpf_access_type type,
                                           const struct bpf_insn *si,
                                           struct bpf_insn *insn_buf,
                                           struct bpf_prog *prog,
                                           u32 *target_size)
{
        struct bpf_insn *insn = insn_buf;

        switch (si->off) {
        case offsetof(struct sk_reuseport_md, data):
                SK_REUSEPORT_LOAD_SKB_FIELD(data);
                break;

        case offsetof(struct sk_reuseport_md, len):
                SK_REUSEPORT_LOAD_SKB_FIELD(len);
                break;

        case offsetof(struct sk_reuseport_md, eth_protocol):
                SK_REUSEPORT_LOAD_SKB_FIELD(protocol);
                break;

        case offsetof(struct sk_reuseport_md, ip_protocol):
                SK_REUSEPORT_LOAD_SK_FIELD(sk_protocol);
                break;

        case offsetof(struct sk_reuseport_md, data_end):
                SK_REUSEPORT_LOAD_FIELD(data_end);
                break;

        case offsetof(struct sk_reuseport_md, hash):
                SK_REUSEPORT_LOAD_FIELD(hash);
                break;

        case offsetof(struct sk_reuseport_md, bind_inany):
                SK_REUSEPORT_LOAD_FIELD(bind_inany);
                break;

        case offsetof(struct sk_reuseport_md, sk):
                SK_REUSEPORT_LOAD_FIELD(sk);
                break;

        case offsetof(struct sk_reuseport_md, migrating_sk):
                SK_REUSEPORT_LOAD_FIELD(migrating_sk);
                break;
        }

        return insn - insn_buf;
}

const struct bpf_verifier_ops sk_reuseport_verifier_ops = {
        .get_func_proto         = sk_reuseport_func_proto,
        .is_valid_access        = sk_reuseport_is_valid_access,
        .convert_ctx_access     = sk_reuseport_convert_ctx_access,
};

const struct bpf_prog_ops sk_reuseport_prog_ops = {
};

DEFINE_STATIC_KEY_FALSE(bpf_sk_lookup_enabled);
EXPORT_SYMBOL(bpf_sk_lookup_enabled);

BPF_CALL_3(bpf_sk_lookup_assign, struct bpf_sk_lookup_kern *, ctx,
           struct sock *, sk, u64, flags)
{
        if (unlikely(flags & ~(BPF_SK_LOOKUP_F_REPLACE |
                               BPF_SK_LOOKUP_F_NO_REUSEPORT)))
                return -EINVAL;
        if (unlikely(sk && sk_is_refcounted(sk)))
                return -ESOCKTNOSUPPORT; /* reject non-RCU freed sockets */
        if (unlikely(sk && sk_is_tcp(sk) && sk->sk_state != TCP_LISTEN))
                return -ESOCKTNOSUPPORT; /* only accept TCP socket in LISTEN */
        if (unlikely(sk && sk_is_udp(sk) && sk->sk_state != TCP_CLOSE))
                return -ESOCKTNOSUPPORT; /* only accept UDP socket in CLOSE */

        /* Check if socket is suitable for packet L3/L4 protocol */
        if (sk && sk->sk_protocol != ctx->protocol)
                return -EPROTOTYPE;
        if (sk && sk->sk_family != ctx->family &&
            (sk->sk_family == AF_INET || ipv6_only_sock(sk)))
                return -EAFNOSUPPORT;

        if (ctx->selected_sk && !(flags & BPF_SK_LOOKUP_F_REPLACE))
                return -EEXIST;

        /* Select socket as lookup result */
        ctx->selected_sk = sk;
        ctx->no_reuseport = flags & BPF_SK_LOOKUP_F_NO_REUSEPORT;
        return 0;
}

static const struct bpf_func_proto bpf_sk_lookup_assign_proto = {
        .func           = bpf_sk_lookup_assign,
        .gpl_only       = false,
        .ret_type       = RET_INTEGER,
        .arg1_type      = ARG_PTR_TO_CTX,
        .arg2_type      = ARG_PTR_TO_SOCKET_OR_NULL,
        .arg3_type      = ARG_ANYTHING,
};

static const struct bpf_func_proto *
sk_lookup_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
        switch (func_id) {
        case BPF_FUNC_perf_event_output:
                return &bpf_event_output_data_proto;
        case BPF_FUNC_sk_assign:
                return &bpf_sk_lookup_assign_proto;
        case BPF_FUNC_sk_release:
                return &bpf_sk_release_proto;
        default:
                return bpf_sk_base_func_proto(func_id, prog);
        }
}

static bool sk_lookup_is_valid_access(int off, int size,
                                      enum bpf_access_type type,
                                      const struct bpf_prog *prog,
                                      struct bpf_insn_access_aux *info)
{
        if (off < 0 || off >= sizeof(struct bpf_sk_lookup))
                return false;
        if (off % size != 0)
                return false;
        if (type != BPF_READ)
                return false;

        switch (off) {
        case bpf_ctx_range_ptr(struct bpf_sk_lookup, sk):
                info->reg_type = PTR_TO_SOCKET_OR_NULL;
                return size == sizeof(__u64);

        case bpf_ctx_range(struct bpf_sk_lookup, family):
        case bpf_ctx_range(struct bpf_sk_lookup, protocol):
        case bpf_ctx_range(struct bpf_sk_lookup, remote_ip4):
        case bpf_ctx_range(struct bpf_sk_lookup, local_ip4):
        case bpf_ctx_range_till(struct bpf_sk_lookup, remote_ip6[0], remote_ip6[3]):
        case bpf_ctx_range_till(struct bpf_sk_lookup, local_ip6[0], local_ip6[3]):
        case bpf_ctx_range(struct bpf_sk_lookup, local_port):
        case bpf_ctx_range(struct bpf_sk_lookup, ingress_ifindex):
                bpf_ctx_record_field_size(info, sizeof(__u32));
                return bpf_ctx_narrow_access_ok(off, size, sizeof(__u32));

        case bpf_ctx_range(struct bpf_sk_lookup, remote_port):
                /* Allow 4-byte access to 2-byte field for backward compatibility */
                if (size == sizeof(__u32))
                        return true;
                bpf_ctx_record_field_size(info, sizeof(__be16));
                return bpf_ctx_narrow_access_ok(off, size, sizeof(__be16));

        case offsetofend(struct bpf_sk_lookup, remote_port) ...
             offsetof(struct bpf_sk_lookup, local_ip4) - 1:
                /* Allow access to zero padding for backward compatibility */
                bpf_ctx_record_field_size(info, sizeof(__u16));
                return bpf_ctx_narrow_access_ok(off, size, sizeof(__u16));

        default:
                return false;
        }
}

static u32 sk_lookup_convert_ctx_access(enum bpf_access_type type,
                                        const struct bpf_insn *si,
                                        struct bpf_insn *insn_buf,
                                        struct bpf_prog *prog,
                                        u32 *target_size)
{
        struct bpf_insn *insn = insn_buf;

        switch (si->off) {
        case offsetof(struct bpf_sk_lookup, sk):
                *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sk_lookup_kern, selected_sk));
                break;

        case offsetof(struct bpf_sk_lookup, family):
                *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
                                      bpf_target_off(struct bpf_sk_lookup_kern,
                                                     family, 2, target_size));
                break;

        case offsetof(struct bpf_sk_lookup, protocol):
                *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
                                      bpf_target_off(struct bpf_sk_lookup_kern,
                                                     protocol, 2, target_size));
                break;

        case offsetof(struct bpf_sk_lookup, remote_ip4):
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
                                      bpf_target_off(struct bpf_sk_lookup_kern,
                                                     v4.saddr, 4, target_size));
                break;

        case offsetof(struct bpf_sk_lookup, local_ip4):
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
                                      bpf_target_off(struct bpf_sk_lookup_kern,
                                                     v4.daddr, 4, target_size));
                break;

        case bpf_ctx_range_till(struct bpf_sk_lookup,
                                remote_ip6[0], remote_ip6[3]): {
#if IS_ENABLED(CONFIG_IPV6)
                int off = si->off;

                off -= offsetof(struct bpf_sk_lookup, remote_ip6[0]);
                off += bpf_target_off(struct in6_addr, s6_addr32[0], 4, target_size);
                *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sk_lookup_kern, v6.saddr));
                *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, off);
#else
                *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
#endif
                break;
        }
        case bpf_ctx_range_till(struct bpf_sk_lookup,
                                local_ip6[0], local_ip6[3]): {
#if IS_ENABLED(CONFIG_IPV6)
                int off = si->off;

                off -= offsetof(struct bpf_sk_lookup, local_ip6[0]);
                off += bpf_target_off(struct in6_addr, s6_addr32[0], 4, target_size);
                *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
                                      offsetof(struct bpf_sk_lookup_kern, v6.daddr));
                *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, off);
#else
                *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
#endif
                break;
        }
        case offsetof(struct bpf_sk_lookup, remote_port):
                *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
                                      bpf_target_off(struct bpf_sk_lookup_kern,
                                                     sport, 2, target_size));
                break;

        case offsetofend(struct bpf_sk_lookup, remote_port):
                *target_size = 2;
                *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
                break;

        case offsetof(struct bpf_sk_lookup, local_port):
                *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
                                      bpf_target_off(struct bpf_sk_lookup_kern,
                                                     dport, 2, target_size));
                break;

        case offsetof(struct bpf_sk_lookup, ingress_ifindex):
                *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
                                      bpf_target_off(struct bpf_sk_lookup_kern,
                                                     ingress_ifindex, 4, target_size));
                break;
        }

        return insn - insn_buf;
}

const struct bpf_prog_ops sk_lookup_prog_ops = {
        .test_run = bpf_prog_test_run_sk_lookup,
};

const struct bpf_verifier_ops sk_lookup_verifier_ops = {
        .get_func_proto         = sk_lookup_func_proto,
        .is_valid_access        = sk_lookup_is_valid_access,
        .convert_ctx_access     = sk_lookup_convert_ctx_access,
};

#endif /* CONFIG_INET */

DEFINE_BPF_DISPATCHER(xdp)

void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog)
{
        bpf_dispatcher_change_prog(BPF_DISPATCHER_PTR(xdp), prev_prog, prog);
}

BTF_ID_LIST_GLOBAL(btf_sock_ids, MAX_BTF_SOCK_TYPE)
#define BTF_SOCK_TYPE(name, type) BTF_ID(struct, type)
BTF_SOCK_TYPE_xxx
#undef BTF_SOCK_TYPE

BPF_CALL_1(bpf_skc_to_tcp6_sock, struct sock *, sk)
{
        /* tcp6_sock type is not generated in dwarf and hence btf,
         * trigger an explicit type generation here.
         */
        BTF_TYPE_EMIT(struct tcp6_sock);
        if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP &&
            sk->sk_type == SOCK_STREAM && sk->sk_family == AF_INET6)
                return (unsigned long)sk;

        return (unsigned long)NULL;
}

const struct bpf_func_proto bpf_skc_to_tcp6_sock_proto = {
        .func                   = bpf_skc_to_tcp6_sock,
        .gpl_only               = false,
        .ret_type               = RET_PTR_TO_BTF_ID_OR_NULL,
        .arg1_type              = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
        .ret_btf_id             = &btf_sock_ids[BTF_SOCK_TYPE_TCP6],
};

BPF_CALL_1(bpf_skc_to_tcp_sock, struct sock *, sk)
{
        if (sk && sk_fullsock(sk) && sk_is_tcp(sk))
                return (unsigned long)sk;

        return (unsigned long)NULL;
}

const struct bpf_func_proto bpf_skc_to_tcp_sock_proto = {
        .func                   = bpf_skc_to_tcp_sock,
        .gpl_only               = false,
        .ret_type               = RET_PTR_TO_BTF_ID_OR_NULL,
        .arg1_type              = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
        .ret_btf_id             = &btf_sock_ids[BTF_SOCK_TYPE_TCP],
};

BPF_CALL_1(bpf_skc_to_tcp_timewait_sock, struct sock *, sk)
{
        /* BTF types for tcp_timewait_sock and inet_timewait_sock are not
         * generated if CONFIG_INET=n. Trigger an explicit generation here.
         */
        BTF_TYPE_EMIT(struct inet_timewait_sock);
        BTF_TYPE_EMIT(struct tcp_timewait_sock);

#ifdef CONFIG_INET
        if (sk && sk->sk_prot == &tcp_prot && sk->sk_state == TCP_TIME_WAIT)
                return (unsigned long)sk;
#endif

#if IS_ENABLED(CONFIG_IPV6)
        if (sk && sk->sk_prot == &tcpv6_prot && sk->sk_state == TCP_TIME_WAIT)
                return (unsigned long)sk;
#endif

        return (unsigned long)NULL;
}

const struct bpf_func_proto bpf_skc_to_tcp_timewait_sock_proto = {
        .func                   = bpf_skc_to_tcp_timewait_sock,
        .gpl_only               = false,
        .ret_type               = RET_PTR_TO_BTF_ID_OR_NULL,
        .arg1_type              = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
        .ret_btf_id             = &btf_sock_ids[BTF_SOCK_TYPE_TCP_TW],
};

BPF_CALL_1(bpf_skc_to_tcp_request_sock, struct sock *, sk)
{
#ifdef CONFIG_INET
        if (sk && sk->sk_prot == &tcp_prot && sk->sk_state == TCP_NEW_SYN_RECV)
                return (unsigned long)sk;
#endif

#if IS_ENABLED(CONFIG_IPV6)
        if (sk && sk->sk_prot == &tcpv6_prot && sk->sk_state == TCP_NEW_SYN_RECV)
                return (unsigned long)sk;
#endif

        return (unsigned long)NULL;
}

const struct bpf_func_proto bpf_skc_to_tcp_request_sock_proto = {
        .func                   = bpf_skc_to_tcp_request_sock,
        .gpl_only               = false,
        .ret_type               = RET_PTR_TO_BTF_ID_OR_NULL,
        .arg1_type              = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
        .ret_btf_id             = &btf_sock_ids[BTF_SOCK_TYPE_TCP_REQ],
};

BPF_CALL_1(bpf_skc_to_udp6_sock, struct sock *, sk)
{
        /* udp6_sock type is not generated in dwarf and hence btf,
         * trigger an explicit type generation here.
         */
        BTF_TYPE_EMIT(struct udp6_sock);
        if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_UDP &&
            sk->sk_type == SOCK_DGRAM && sk->sk_family == AF_INET6)
                return (unsigned long)sk;

        return (unsigned long)NULL;
}

const struct bpf_func_proto bpf_skc_to_udp6_sock_proto = {
        .func                   = bpf_skc_to_udp6_sock,
        .gpl_only               = false,
        .ret_type               = RET_PTR_TO_BTF_ID_OR_NULL,
        .arg1_type              = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
        .ret_btf_id             = &btf_sock_ids[BTF_SOCK_TYPE_UDP6],
};

BPF_CALL_1(bpf_skc_to_unix_sock, struct sock *, sk)
{
        /* unix_sock type is not generated in dwarf and hence btf,
         * trigger an explicit type generation here.
         */
        BTF_TYPE_EMIT(struct unix_sock);
        if (sk && sk_is_unix(sk))
                return (unsigned long)sk;

        return (unsigned long)NULL;
}

const struct bpf_func_proto bpf_skc_to_unix_sock_proto = {
        .func                   = bpf_skc_to_unix_sock,
        .gpl_only               = false,
        .ret_type               = RET_PTR_TO_BTF_ID_OR_NULL,
        .arg1_type              = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
        .ret_btf_id             = &btf_sock_ids[BTF_SOCK_TYPE_UNIX],
};

BPF_CALL_1(bpf_skc_to_mptcp_sock, struct sock *, sk)
{
        BTF_TYPE_EMIT(struct mptcp_sock);
        return (unsigned long)bpf_mptcp_sock_from_subflow(sk);
}

const struct bpf_func_proto bpf_skc_to_mptcp_sock_proto = {
        .func           = bpf_skc_to_mptcp_sock,
        .gpl_only       = false,
        .ret_type       = RET_PTR_TO_BTF_ID_OR_NULL,
        .arg1_type      = ARG_PTR_TO_SOCK_COMMON,
        .ret_btf_id     = &btf_sock_ids[BTF_SOCK_TYPE_MPTCP],
};

BPF_CALL_1(bpf_sock_from_file, struct file *, file)
{
        return (unsigned long)sock_from_file(file);
}

BTF_ID_LIST(bpf_sock_from_file_btf_ids)
BTF_ID(struct, socket)
BTF_ID(struct, file)

const struct bpf_func_proto bpf_sock_from_file_proto = {
        .func           = bpf_sock_from_file,
        .gpl_only       = false,
        .ret_type       = RET_PTR_TO_BTF_ID_OR_NULL,
        .ret_btf_id     = &bpf_sock_from_file_btf_ids[0],
        .arg1_type      = ARG_PTR_TO_BTF_ID,
        .arg1_btf_id    = &bpf_sock_from_file_btf_ids[1],
};

static const struct bpf_func_proto *
bpf_sk_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
        const struct bpf_func_proto *func;

        switch (func_id) {
        case BPF_FUNC_skc_to_tcp6_sock:
                func = &bpf_skc_to_tcp6_sock_proto;
                break;
        case BPF_FUNC_skc_to_tcp_sock:
                func = &bpf_skc_to_tcp_sock_proto;
                break;
        case BPF_FUNC_skc_to_tcp_timewait_sock:
                func = &bpf_skc_to_tcp_timewait_sock_proto;
                break;
        case BPF_FUNC_skc_to_tcp_request_sock:
                func = &bpf_skc_to_tcp_request_sock_proto;
                break;
        case BPF_FUNC_skc_to_udp6_sock:
                func = &bpf_skc_to_udp6_sock_proto;
                break;
        case BPF_FUNC_skc_to_unix_sock:
                func = &bpf_skc_to_unix_sock_proto;
                break;
        case BPF_FUNC_skc_to_mptcp_sock:
                func = &bpf_skc_to_mptcp_sock_proto;
                break;
        case BPF_FUNC_ktime_get_coarse_ns:
                return &bpf_ktime_get_coarse_ns_proto;
        default:
                return bpf_base_func_proto(func_id, prog);
        }

        if (!bpf_token_capable(prog->aux->token, CAP_PERFMON))
                return NULL;

        return func;
}

/**
 * bpf_skb_meta_pointer() - Gets a mutable pointer within the skb metadata area.
 * @skb: socket buffer carrying the metadata
 * @offset: offset into the metadata area, must be <= skb_metadata_len()
 */
void *bpf_skb_meta_pointer(struct sk_buff *skb, u32 offset)
{
        return skb_metadata_end(skb) - skb_metadata_len(skb) + offset;
}

int __bpf_skb_meta_store_bytes(struct sk_buff *skb, u32 offset,
                               const void *from, u32 len, u64 flags)
{
        if (unlikely(flags))
                return -EINVAL;
        if (unlikely(bpf_try_make_writable(skb, 0)))
                return -EFAULT;

        memmove(bpf_skb_meta_pointer(skb, offset), from, len);
        return 0;
}

__bpf_kfunc_start_defs();
__bpf_kfunc int bpf_dynptr_from_skb(struct __sk_buff *s, u64 flags,
                                    struct bpf_dynptr *ptr__uninit)
{
        struct bpf_dynptr_kern *ptr = (struct bpf_dynptr_kern *)ptr__uninit;
        struct sk_buff *skb = (struct sk_buff *)s;

        if (flags) {
                bpf_dynptr_set_null(ptr);
                return -EINVAL;
        }

        bpf_dynptr_init(ptr, skb, BPF_DYNPTR_TYPE_SKB, 0, skb->len);

        return 0;
}

/**
 * bpf_dynptr_from_skb_meta() - Initialize a dynptr to the skb metadata area.
 * @skb_: socket buffer carrying the metadata
 * @flags: future use, must be zero
 * @ptr__uninit: dynptr to initialize
 *
 * Set up a dynptr for access to the metadata area earlier allocated from the
 * XDP context with bpf_xdp_adjust_meta(). Serves as an alternative to
 * &__sk_buff->data_meta.
 *
 * Return:
 * * %0         - dynptr ready to use
 * * %-EINVAL   - invalid flags, dynptr set to null
 */
__bpf_kfunc int bpf_dynptr_from_skb_meta(struct __sk_buff *skb_, u64 flags,
                                         struct bpf_dynptr *ptr__uninit)
{
        struct bpf_dynptr_kern *ptr = (struct bpf_dynptr_kern *)ptr__uninit;
        struct sk_buff *skb = (struct sk_buff *)skb_;

        if (flags) {
                bpf_dynptr_set_null(ptr);
                return -EINVAL;
        }

        bpf_dynptr_init(ptr, skb, BPF_DYNPTR_TYPE_SKB_META, 0, skb_metadata_len(skb));

        return 0;
}

__bpf_kfunc int bpf_dynptr_from_xdp(struct xdp_md *x, u64 flags,
                                    struct bpf_dynptr *ptr__uninit)
{
        struct bpf_dynptr_kern *ptr = (struct bpf_dynptr_kern *)ptr__uninit;
        struct xdp_buff *xdp = (struct xdp_buff *)x;

        if (flags) {
                bpf_dynptr_set_null(ptr);
                return -EINVAL;
        }

        bpf_dynptr_init(ptr, xdp, BPF_DYNPTR_TYPE_XDP, 0, xdp_get_buff_len(xdp));

        return 0;
}

__bpf_kfunc int bpf_sock_addr_set_sun_path(struct bpf_sock_addr_kern *sa_kern,
                                           const u8 *sun_path, u32 sun_path__sz)
{
        struct sockaddr_un *un;

        if (sa_kern->sk->sk_family != AF_UNIX)
                return -EINVAL;

        /* We do not allow changing the address to unnamed or larger than the
         * maximum allowed address size for a unix sockaddr.
         */
        if (sun_path__sz == 0 || sun_path__sz > UNIX_PATH_MAX)
                return -EINVAL;

        un = (struct sockaddr_un *)sa_kern->uaddr;
        memcpy(un->sun_path, sun_path, sun_path__sz);
        sa_kern->uaddrlen = offsetof(struct sockaddr_un, sun_path) + sun_path__sz;

        return 0;
}

__bpf_kfunc int bpf_sk_assign_tcp_reqsk(struct __sk_buff *s, struct sock *sk,
                                        struct bpf_tcp_req_attrs *attrs, int attrs__sz)
{
#if IS_ENABLED(CONFIG_SYN_COOKIES)
        struct sk_buff *skb = (struct sk_buff *)s;
        const struct request_sock_ops *ops;
        struct inet_request_sock *ireq;
        struct tcp_request_sock *treq;
        struct request_sock *req;
        struct net *net;
        __u16 min_mss;
        u32 tsoff = 0;

        if (attrs__sz != sizeof(*attrs) ||
            attrs->reserved[0] || attrs->reserved[1] || attrs->reserved[2])
                return -EINVAL;

        if (!skb_at_tc_ingress(skb))
                return -EINVAL;

        net = dev_net(skb->dev);
        if (net != sock_net(sk))
                return -ENETUNREACH;

        switch (skb->protocol) {
        case htons(ETH_P_IP):
                ops = &tcp_request_sock_ops;
                min_mss = 536;
                break;
#if IS_ENABLED(CONFIG_IPV6)
        case htons(ETH_P_IPV6):
                ops = &tcp6_request_sock_ops;
                min_mss = IPV6_MIN_MTU - 60;
                break;
#endif
        default:
                return -EINVAL;
        }

        if (sk->sk_type != SOCK_STREAM || sk->sk_state != TCP_LISTEN ||
            sk_is_mptcp(sk))
                return -EINVAL;

        if (attrs->mss < min_mss)
                return -EINVAL;

        if (attrs->wscale_ok) {
                if (!READ_ONCE(net->ipv4.sysctl_tcp_window_scaling))
                        return -EINVAL;

                if (attrs->snd_wscale > TCP_MAX_WSCALE ||
                    attrs->rcv_wscale > TCP_MAX_WSCALE)
                        return -EINVAL;
        }

        if (attrs->sack_ok && !READ_ONCE(net->ipv4.sysctl_tcp_sack))
                return -EINVAL;

        if (attrs->tstamp_ok) {
                if (!READ_ONCE(net->ipv4.sysctl_tcp_timestamps))
                        return -EINVAL;

                tsoff = attrs->rcv_tsecr - tcp_ns_to_ts(attrs->usec_ts_ok, tcp_clock_ns());
        }

        req = inet_reqsk_alloc(ops, sk, false);
        if (!req)
                return -ENOMEM;

        ireq = inet_rsk(req);
        treq = tcp_rsk(req);

        req->rsk_listener = sk;
        req->syncookie = 1;
        req->mss = attrs->mss;
        req->ts_recent = attrs->rcv_tsval;

        ireq->snd_wscale = attrs->snd_wscale;
        ireq->rcv_wscale = attrs->rcv_wscale;
        ireq->tstamp_ok = !!attrs->tstamp_ok;
        ireq->sack_ok = !!attrs->sack_ok;
        ireq->wscale_ok = !!attrs->wscale_ok;
        ireq->ecn_ok = !!attrs->ecn_ok;

        treq->req_usec_ts = !!attrs->usec_ts_ok;
        treq->ts_off = tsoff;

        skb_orphan(skb);
        skb->sk = req_to_sk(req);
        skb->destructor = sock_pfree;

        return 0;
#else
        return -EOPNOTSUPP;
#endif
}

__bpf_kfunc int bpf_sock_ops_enable_tx_tstamp(struct bpf_sock_ops_kern *skops,
                                              u64 flags)
{
        struct sk_buff *skb;

        if (skops->op != BPF_SOCK_OPS_TSTAMP_SENDMSG_CB)
                return -EOPNOTSUPP;

        if (flags)
                return -EINVAL;

        skb = skops->skb;
        skb_shinfo(skb)->tx_flags |= SKBTX_BPF;
        TCP_SKB_CB(skb)->txstamp_ack |= TSTAMP_ACK_BPF;
        skb_shinfo(skb)->tskey = TCP_SKB_CB(skb)->seq + skb->len - 1;

        return 0;
}

/**
 * bpf_xdp_pull_data() - Pull in non-linear xdp data.
 * @x: &xdp_md associated with the XDP buffer
 * @len: length of data to be made directly accessible in the linear part
 *
 * Pull in data in case the XDP buffer associated with @x is non-linear and
 * not all @len are in the linear data area.
 *
 * Direct packet access allows reading and writing linear XDP data through
 * packet pointers (i.e., &xdp_md->data + offsets). The amount of data which
 * ends up in the linear part of the xdp_buff depends on the NIC and its
 * configuration. When a frag-capable XDP program wants to directly access
 * headers that may be in the non-linear area, call this kfunc to make sure
 * the data is available in the linear area. Alternatively, use dynptr or
 * bpf_xdp_{load,store}_bytes() to access data without pulling.
 *
 * This kfunc can also be used with bpf_xdp_adjust_head() to decapsulate
 * headers in the non-linear data area.
 *
 * A call to this kfunc may reduce headroom. If there is not enough tailroom
 * in the linear data area, metadata and data will be shifted down.
 *
 * A call to this kfunc is susceptible to change the buffer geometry.
 * Therefore, at load time, all checks on pointers previously done by the
 * verifier are invalidated and must be performed again, if the kfunc is used
 * in combination with direct packet access.
 *
 * Return:
 * * %0         - success
 * * %-EINVAL   - invalid len
 */
__bpf_kfunc int bpf_xdp_pull_data(struct xdp_md *x, u32 len)
{
        struct xdp_buff *xdp = (struct xdp_buff *)x;
        struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
        int i, delta, shift, headroom, tailroom, n_frags_free = 0;
        void *data_hard_end = xdp_data_hard_end(xdp);
        int data_len = xdp->data_end - xdp->data;
        void *start;

        if (len <= data_len)
                return 0;

        if (unlikely(len > xdp_get_buff_len(xdp)))
                return -EINVAL;

        start = xdp_data_meta_unsupported(xdp) ? xdp->data : xdp->data_meta;

        headroom = start - xdp->data_hard_start - sizeof(struct xdp_frame);
        tailroom = data_hard_end - xdp->data_end;

        delta = len - data_len;
        if (unlikely(delta > tailroom + headroom))
                return -EINVAL;

        shift = delta - tailroom;
        if (shift > 0) {
                memmove(start - shift, start, xdp->data_end - start);

                xdp->data_meta -= shift;
                xdp->data -= shift;
                xdp->data_end -= shift;
        }

        for (i = 0; i < sinfo->nr_frags && delta; i++) {
                skb_frag_t *frag = &sinfo->frags[i];
                u32 shrink = min_t(u32, delta, skb_frag_size(frag));

                memcpy(xdp->data_end, skb_frag_address(frag), shrink);

                xdp->data_end += shrink;
                sinfo->xdp_frags_size -= shrink;
                delta -= shrink;
                if (bpf_xdp_shrink_data(xdp, frag, shrink, false))
                        n_frags_free++;
        }

        if (unlikely(n_frags_free)) {
                memmove(sinfo->frags, sinfo->frags + n_frags_free,
                        (sinfo->nr_frags - n_frags_free) * sizeof(skb_frag_t));

                sinfo->nr_frags -= n_frags_free;

                if (!sinfo->nr_frags) {
                        xdp_buff_clear_frags_flag(xdp);
                        xdp_buff_clear_frag_pfmemalloc(xdp);
                }
        }

        return 0;
}

__bpf_kfunc_end_defs();

int bpf_dynptr_from_skb_rdonly(struct __sk_buff *skb, u64 flags,
                               struct bpf_dynptr *ptr__uninit)
{
        struct bpf_dynptr_kern *ptr = (struct bpf_dynptr_kern *)ptr__uninit;
        int err;

        err = bpf_dynptr_from_skb(skb, flags, ptr__uninit);
        if (err)
                return err;

        bpf_dynptr_set_rdonly(ptr);

        return 0;
}

BTF_KFUNCS_START(bpf_kfunc_check_set_skb)
BTF_ID_FLAGS(func, bpf_dynptr_from_skb)
BTF_KFUNCS_END(bpf_kfunc_check_set_skb)

BTF_KFUNCS_START(bpf_kfunc_check_set_skb_meta)
BTF_ID_FLAGS(func, bpf_dynptr_from_skb_meta)
BTF_KFUNCS_END(bpf_kfunc_check_set_skb_meta)

BTF_KFUNCS_START(bpf_kfunc_check_set_xdp)
BTF_ID_FLAGS(func, bpf_dynptr_from_xdp)
BTF_ID_FLAGS(func, bpf_xdp_pull_data)
BTF_KFUNCS_END(bpf_kfunc_check_set_xdp)

BTF_KFUNCS_START(bpf_kfunc_check_set_sock_addr)
BTF_ID_FLAGS(func, bpf_sock_addr_set_sun_path)
BTF_KFUNCS_END(bpf_kfunc_check_set_sock_addr)

BTF_KFUNCS_START(bpf_kfunc_check_set_tcp_reqsk)
BTF_ID_FLAGS(func, bpf_sk_assign_tcp_reqsk)
BTF_KFUNCS_END(bpf_kfunc_check_set_tcp_reqsk)

BTF_KFUNCS_START(bpf_kfunc_check_set_sock_ops)
BTF_ID_FLAGS(func, bpf_sock_ops_enable_tx_tstamp)
BTF_KFUNCS_END(bpf_kfunc_check_set_sock_ops)

static const struct btf_kfunc_id_set bpf_kfunc_set_skb = {
        .owner = THIS_MODULE,
        .set = &bpf_kfunc_check_set_skb,
};

static const struct btf_kfunc_id_set bpf_kfunc_set_skb_meta = {
        .owner = THIS_MODULE,
        .set = &bpf_kfunc_check_set_skb_meta,
};

static const struct btf_kfunc_id_set bpf_kfunc_set_xdp = {
        .owner = THIS_MODULE,
        .set = &bpf_kfunc_check_set_xdp,
};

static const struct btf_kfunc_id_set bpf_kfunc_set_sock_addr = {
        .owner = THIS_MODULE,
        .set = &bpf_kfunc_check_set_sock_addr,
};

static const struct btf_kfunc_id_set bpf_kfunc_set_tcp_reqsk = {
        .owner = THIS_MODULE,
        .set = &bpf_kfunc_check_set_tcp_reqsk,
};

static const struct btf_kfunc_id_set bpf_kfunc_set_sock_ops = {
        .owner = THIS_MODULE,
        .set = &bpf_kfunc_check_set_sock_ops,
};

static int __init bpf_kfunc_init(void)
{
        int ret;

        ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &bpf_kfunc_set_skb);
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_ACT, &bpf_kfunc_set_skb);
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SK_SKB, &bpf_kfunc_set_skb);
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SOCKET_FILTER, &bpf_kfunc_set_skb);
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_CGROUP_SKB, &bpf_kfunc_set_skb);
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_LWT_OUT, &bpf_kfunc_set_skb);
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_LWT_IN, &bpf_kfunc_set_skb);
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_LWT_XMIT, &bpf_kfunc_set_skb);
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_LWT_SEG6LOCAL, &bpf_kfunc_set_skb);
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_NETFILTER, &bpf_kfunc_set_skb);
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &bpf_kfunc_set_skb);
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &bpf_kfunc_set_skb_meta);
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_ACT, &bpf_kfunc_set_skb_meta);
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_XDP, &bpf_kfunc_set_xdp);
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
                                               &bpf_kfunc_set_sock_addr);
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &bpf_kfunc_set_tcp_reqsk);
        return ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SOCK_OPS, &bpf_kfunc_set_sock_ops);
}
late_initcall(bpf_kfunc_init);

__bpf_kfunc_start_defs();

/* bpf_sock_destroy: Destroy the given socket with ECONNABORTED error code.
 *
 * The function expects a non-NULL pointer to a socket, and invokes the
 * protocol specific socket destroy handlers.
 *
 * The helper can only be called from BPF contexts that have acquired the socket
 * locks.
 *
 * Parameters:
 * @sock: Pointer to socket to be destroyed
 *
 * Return:
 * On error, may return EPROTONOSUPPORT, EINVAL.
 * EPROTONOSUPPORT if protocol specific destroy handler is not supported.
 * 0 otherwise
 */
__bpf_kfunc int bpf_sock_destroy(struct sock_common *sock)
{
        struct sock *sk = (struct sock *)sock;

        /* The locking semantics that allow for synchronous execution of the
         * destroy handlers are only supported for TCP and UDP.
         * Supporting protocols will need to acquire sock lock in the BPF context
         * prior to invoking this kfunc.
         */
        if (!sk->sk_prot->diag_destroy || (sk->sk_protocol != IPPROTO_TCP &&
                                           sk->sk_protocol != IPPROTO_UDP))
                return -EOPNOTSUPP;

        return sk->sk_prot->diag_destroy(sk, ECONNABORTED);
}

__bpf_kfunc_end_defs();

BTF_KFUNCS_START(bpf_sk_iter_kfunc_ids)
BTF_ID_FLAGS(func, bpf_sock_destroy)
BTF_KFUNCS_END(bpf_sk_iter_kfunc_ids)

static int tracing_iter_filter(const struct bpf_prog *prog, u32 kfunc_id)
{
        if (btf_id_set8_contains(&bpf_sk_iter_kfunc_ids, kfunc_id) &&
            prog->expected_attach_type != BPF_TRACE_ITER)
                return -EACCES;
        return 0;
}

static const struct btf_kfunc_id_set bpf_sk_iter_kfunc_set = {
        .owner = THIS_MODULE,
        .set   = &bpf_sk_iter_kfunc_ids,
        .filter = tracing_iter_filter,
};

static int init_subsystem(void)
{
        return register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &bpf_sk_iter_kfunc_set);
}
late_initcall(init_subsystem);