// SPDX-License-Identifier: GPL-2.0-only
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/export.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/if_vlan.h>
#include <linux/filter.h>
#include <net/dsa.h>
#include <net/dst_metadata.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <net/gre.h>
#include <net/pptp.h>
#include <net/tipc.h>
#include <linux/igmp.h>
#include <linux/icmp.h>
#include <linux/sctp.h>
#include <linux/dccp.h>
#include <linux/if_tunnel.h>
#include <linux/if_pppox.h>
#include <linux/ppp_defs.h>
#include <linux/stddef.h>
#include <linux/if_ether.h>
#include <linux/if_hsr.h>
#include <linux/mpls.h>
#include <linux/tcp.h>
#include <linux/ptp_classify.h>
#include <net/flow_dissector.h>
#include <net/pkt_cls.h>
#include <scsi/fc/fc_fcoe.h>
#include <uapi/linux/batadv_packet.h>
#include <linux/bpf.h>
#if IS_ENABLED(CONFIG_NF_CONNTRACK)
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/nf_conntrack_labels.h>
#endif
#include <linux/bpf-netns.h>

static void dissector_set_key(struct flow_dissector *flow_dissector,
                              enum flow_dissector_key_id key_id)
{
        flow_dissector->used_keys |= (1ULL << key_id);
}

void skb_flow_dissector_init(struct flow_dissector *flow_dissector,
                             const struct flow_dissector_key *key,
                             unsigned int key_count)
{
        unsigned int i;

        memset(flow_dissector, 0, sizeof(*flow_dissector));

        for (i = 0; i < key_count; i++, key++) {
                /* User should make sure that every key target offset is within
                 * boundaries of unsigned short.
                 */
                BUG_ON(key->offset > USHRT_MAX);
                BUG_ON(dissector_uses_key(flow_dissector,
                                          key->key_id));

                dissector_set_key(flow_dissector, key->key_id);
                flow_dissector->offset[key->key_id] = key->offset;
        }

        /* Ensure that the dissector always includes control and basic key.
         * That way we are able to avoid handling lack of these in fast path.
         */
        BUG_ON(!dissector_uses_key(flow_dissector,
                                   FLOW_DISSECTOR_KEY_CONTROL));
        BUG_ON(!dissector_uses_key(flow_dissector,
                                   FLOW_DISSECTOR_KEY_BASIC));
}
EXPORT_SYMBOL(skb_flow_dissector_init);

#ifdef CONFIG_BPF_SYSCALL
int flow_dissector_bpf_prog_attach_check(struct net *net,
                                         struct bpf_prog *prog)
{
        enum netns_bpf_attach_type type = NETNS_BPF_FLOW_DISSECTOR;

        if (net == &init_net) {
                /* BPF flow dissector in the root namespace overrides
                 * any per-net-namespace one. When attaching to root,
                 * make sure we don't have any BPF program attached
                 * to the non-root namespaces.
                 */
                struct net *ns;

                for_each_net(ns) {
                        if (ns == &init_net)
                                continue;
                        if (rcu_access_pointer(ns->bpf.run_array[type]))
                                return -EEXIST;
                }
        } else {
                /* Make sure root flow dissector is not attached
                 * when attaching to the non-root namespace.
                 */
                if (rcu_access_pointer(init_net.bpf.run_array[type]))
                        return -EEXIST;
        }

        return 0;
}
#endif /* CONFIG_BPF_SYSCALL */

/**
 * skb_flow_get_ports - extract the upper layer ports and return them
 * @skb: sk_buff to extract the ports from
 * @thoff: transport header offset
 * @ip_proto: protocol for which to get port offset
 * @data: raw buffer pointer to the packet, if NULL use skb->data
 * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
 *
 * The function will try to retrieve the ports at offset thoff + poff where poff
 * is the protocol port offset returned from proto_ports_offset
 */
__be32 skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
                          const void *data, int hlen)
{
        int poff = proto_ports_offset(ip_proto);

        if (!data) {
                data = skb->data;
                hlen = skb_headlen(skb);
        }

        if (poff >= 0) {
                __be32 *ports, _ports;

                ports = __skb_header_pointer(skb, thoff + poff,
                                             sizeof(_ports), data, hlen, &_ports);
                if (ports)
                        return *ports;
        }

        return 0;
}
EXPORT_SYMBOL(skb_flow_get_ports);

static bool icmp_has_id(u8 type)
{
        switch (type) {
        case ICMP_ECHO:
        case ICMP_ECHOREPLY:
        case ICMP_TIMESTAMP:
        case ICMP_TIMESTAMPREPLY:
        case ICMPV6_ECHO_REQUEST:
        case ICMPV6_ECHO_REPLY:
                return true;
        }

        return false;
}

/**
 * skb_flow_get_icmp_tci - extract ICMP(6) Type, Code and Identifier fields
 * @skb: sk_buff to extract from
 * @key_icmp: struct flow_dissector_key_icmp to fill
 * @data: raw buffer pointer to the packet
 * @thoff: offset to extract at
 * @hlen: packet header length
 */
void skb_flow_get_icmp_tci(const struct sk_buff *skb,
                           struct flow_dissector_key_icmp *key_icmp,
                           const void *data, int thoff, int hlen)
{
        struct icmphdr *ih, _ih;

        ih = __skb_header_pointer(skb, thoff, sizeof(_ih), data, hlen, &_ih);
        if (!ih)
                return;

        key_icmp->type = ih->type;
        key_icmp->code = ih->code;

        /* As we use 0 to signal that the Id field is not present,
         * avoid confusion with packets without such field
         */
        if (icmp_has_id(ih->type))
                key_icmp->id = ih->un.echo.id ? ntohs(ih->un.echo.id) : 1;
        else
                key_icmp->id = 0;
}
EXPORT_SYMBOL(skb_flow_get_icmp_tci);

/* If FLOW_DISSECTOR_KEY_ICMP is set, dissect an ICMP packet
 * using skb_flow_get_icmp_tci().
 */
static void __skb_flow_dissect_icmp(const struct sk_buff *skb,
                                    struct flow_dissector *flow_dissector,
                                    void *target_container, const void *data,
                                    int thoff, int hlen)
{
        struct flow_dissector_key_icmp *key_icmp;

        if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ICMP))
                return;

        key_icmp = skb_flow_dissector_target(flow_dissector,
                                             FLOW_DISSECTOR_KEY_ICMP,
                                             target_container);

        skb_flow_get_icmp_tci(skb, key_icmp, data, thoff, hlen);
}

static void __skb_flow_dissect_ah(const struct sk_buff *skb,
                                  struct flow_dissector *flow_dissector,
                                  void *target_container, const void *data,
                                  int nhoff, int hlen)
{
        struct flow_dissector_key_ipsec *key_ah;
        struct ip_auth_hdr _hdr, *hdr;

        if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPSEC))
                return;

        hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
        if (!hdr)
                return;

        key_ah = skb_flow_dissector_target(flow_dissector,
                                           FLOW_DISSECTOR_KEY_IPSEC,
                                           target_container);

        key_ah->spi = hdr->spi;
}

static void __skb_flow_dissect_esp(const struct sk_buff *skb,
                                   struct flow_dissector *flow_dissector,
                                   void *target_container, const void *data,
                                   int nhoff, int hlen)
{
        struct flow_dissector_key_ipsec *key_esp;
        struct ip_esp_hdr _hdr, *hdr;

        if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPSEC))
                return;

        hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
        if (!hdr)
                return;

        key_esp = skb_flow_dissector_target(flow_dissector,
                                            FLOW_DISSECTOR_KEY_IPSEC,
                                            target_container);

        key_esp->spi = hdr->spi;
}

static void __skb_flow_dissect_l2tpv3(const struct sk_buff *skb,
                                      struct flow_dissector *flow_dissector,
                                      void *target_container, const void *data,
                                      int nhoff, int hlen)
{
        struct flow_dissector_key_l2tpv3 *key_l2tpv3;
        struct {
                __be32 session_id;
        } *hdr, _hdr;

        if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_L2TPV3))
                return;

        hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
        if (!hdr)
                return;

        key_l2tpv3 = skb_flow_dissector_target(flow_dissector,
                                               FLOW_DISSECTOR_KEY_L2TPV3,
                                               target_container);

        key_l2tpv3->session_id = hdr->session_id;
}

void skb_flow_dissect_meta(const struct sk_buff *skb,
                           struct flow_dissector *flow_dissector,
                           void *target_container)
{
        struct flow_dissector_key_meta *meta;

        if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_META))
                return;

        meta = skb_flow_dissector_target(flow_dissector,
                                         FLOW_DISSECTOR_KEY_META,
                                         target_container);
        meta->ingress_ifindex = skb->skb_iif;
#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
        if (tc_skb_ext_tc_enabled()) {
                struct tc_skb_ext *ext;

                ext = skb_ext_find(skb, TC_SKB_EXT);
                if (ext)
                        meta->l2_miss = ext->l2_miss;
        }
#endif
}
EXPORT_SYMBOL(skb_flow_dissect_meta);

static void
skb_flow_dissect_set_enc_control(enum flow_dissector_key_id type,
                                 u32 ctrl_flags,
                                 struct flow_dissector *flow_dissector,
                                 void *target_container)
{
        struct flow_dissector_key_control *ctrl;

        if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_CONTROL))
                return;

        ctrl = skb_flow_dissector_target(flow_dissector,
                                         FLOW_DISSECTOR_KEY_ENC_CONTROL,
                                         target_container);
        ctrl->addr_type = type;
        ctrl->flags = ctrl_flags;
}

void
skb_flow_dissect_ct(const struct sk_buff *skb,
                    struct flow_dissector *flow_dissector,
                    void *target_container, u16 *ctinfo_map,
                    size_t mapsize, bool post_ct, u16 zone)
{
#if IS_ENABLED(CONFIG_NF_CONNTRACK)
        struct flow_dissector_key_ct *key;
        enum ip_conntrack_info ctinfo;
        struct nf_conn_labels *cl;
        struct nf_conn *ct;

        if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_CT))
                return;

        ct = nf_ct_get(skb, &ctinfo);
        if (!ct && !post_ct)
                return;

        key = skb_flow_dissector_target(flow_dissector,
                                        FLOW_DISSECTOR_KEY_CT,
                                        target_container);

        if (!ct) {
                key->ct_state = TCA_FLOWER_KEY_CT_FLAGS_TRACKED |
                                TCA_FLOWER_KEY_CT_FLAGS_INVALID;
                key->ct_zone = zone;
                return;
        }

        if (ctinfo < mapsize)
                key->ct_state = ctinfo_map[ctinfo];
#if IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)
        key->ct_zone = ct->zone.id;
#endif
#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
        key->ct_mark = READ_ONCE(ct->mark);
#endif

        cl = nf_ct_labels_find(ct);
        if (cl)
                memcpy(key->ct_labels, cl->bits, sizeof(key->ct_labels));
#endif /* CONFIG_NF_CONNTRACK */
}
EXPORT_SYMBOL(skb_flow_dissect_ct);

void
skb_flow_dissect_tunnel_info(const struct sk_buff *skb,
                             struct flow_dissector *flow_dissector,
                             void *target_container)
{
        struct ip_tunnel_info *info;
        struct ip_tunnel_key *key;
        u32 ctrl_flags = 0;

        /* A quick check to see if there might be something to do. */
        if (!dissector_uses_key(flow_dissector,
                                FLOW_DISSECTOR_KEY_ENC_KEYID) &&
            !dissector_uses_key(flow_dissector,
                                FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS) &&
            !dissector_uses_key(flow_dissector,
                                FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS) &&
            !dissector_uses_key(flow_dissector,
                                FLOW_DISSECTOR_KEY_ENC_CONTROL) &&
            !dissector_uses_key(flow_dissector,
                                FLOW_DISSECTOR_KEY_ENC_PORTS) &&
            !dissector_uses_key(flow_dissector,
                                FLOW_DISSECTOR_KEY_ENC_IP) &&
            !dissector_uses_key(flow_dissector,
                                FLOW_DISSECTOR_KEY_ENC_OPTS))
                return;

        info = skb_tunnel_info(skb);
        if (!info)
                return;

        key = &info->key;

        if (test_bit(IP_TUNNEL_CSUM_BIT, key->tun_flags))
                ctrl_flags |= FLOW_DIS_F_TUNNEL_CSUM;
        if (test_bit(IP_TUNNEL_DONT_FRAGMENT_BIT, key->tun_flags))
                ctrl_flags |= FLOW_DIS_F_TUNNEL_DONT_FRAGMENT;
        if (test_bit(IP_TUNNEL_OAM_BIT, key->tun_flags))
                ctrl_flags |= FLOW_DIS_F_TUNNEL_OAM;
        if (test_bit(IP_TUNNEL_CRIT_OPT_BIT, key->tun_flags))
                ctrl_flags |= FLOW_DIS_F_TUNNEL_CRIT_OPT;

        switch (ip_tunnel_info_af(info)) {
        case AF_INET:
                skb_flow_dissect_set_enc_control(FLOW_DISSECTOR_KEY_IPV4_ADDRS,
                                                 ctrl_flags, flow_dissector,
                                                 target_container);
                if (dissector_uses_key(flow_dissector,
                                       FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS)) {
                        struct flow_dissector_key_ipv4_addrs *ipv4;

                        ipv4 = skb_flow_dissector_target(flow_dissector,
                                                         FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS,
                                                         target_container);
                        ipv4->src = key->u.ipv4.src;
                        ipv4->dst = key->u.ipv4.dst;
                }
                break;
        case AF_INET6:
                skb_flow_dissect_set_enc_control(FLOW_DISSECTOR_KEY_IPV6_ADDRS,
                                                 ctrl_flags, flow_dissector,
                                                 target_container);
                if (dissector_uses_key(flow_dissector,
                                       FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS)) {
                        struct flow_dissector_key_ipv6_addrs *ipv6;

                        ipv6 = skb_flow_dissector_target(flow_dissector,
                                                         FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS,
                                                         target_container);
                        ipv6->src = key->u.ipv6.src;
                        ipv6->dst = key->u.ipv6.dst;
                }
                break;
        default:
                skb_flow_dissect_set_enc_control(0, ctrl_flags, flow_dissector,
                                                 target_container);
                break;
        }

        if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_KEYID)) {
                struct flow_dissector_key_keyid *keyid;

                keyid = skb_flow_dissector_target(flow_dissector,
                                                  FLOW_DISSECTOR_KEY_ENC_KEYID,
                                                  target_container);
                keyid->keyid = tunnel_id_to_key32(key->tun_id);
        }

        if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_PORTS)) {
                struct flow_dissector_key_ports *tp;

                tp = skb_flow_dissector_target(flow_dissector,
                                               FLOW_DISSECTOR_KEY_ENC_PORTS,
                                               target_container);
                tp->src = key->tp_src;
                tp->dst = key->tp_dst;
        }

        if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_IP)) {
                struct flow_dissector_key_ip *ip;

                ip = skb_flow_dissector_target(flow_dissector,
                                               FLOW_DISSECTOR_KEY_ENC_IP,
                                               target_container);
                ip->tos = key->tos;
                ip->ttl = key->ttl;
        }

        if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_OPTS)) {
                struct flow_dissector_key_enc_opts *enc_opt;
                IP_TUNNEL_DECLARE_FLAGS(flags) = { };
                u32 val;

                enc_opt = skb_flow_dissector_target(flow_dissector,
                                                    FLOW_DISSECTOR_KEY_ENC_OPTS,
                                                    target_container);

                if (!info->options_len)
                        return;

                enc_opt->len = info->options_len;
                ip_tunnel_info_opts_get(enc_opt->data, info);

                ip_tunnel_set_options_present(flags);
                ip_tunnel_flags_and(flags, info->key.tun_flags, flags);

                val = find_next_bit(flags, __IP_TUNNEL_FLAG_NUM,
                                    IP_TUNNEL_GENEVE_OPT_BIT);
                enc_opt->dst_opt_type = val < __IP_TUNNEL_FLAG_NUM ? val : 0;
        }
}
EXPORT_SYMBOL(skb_flow_dissect_tunnel_info);

void skb_flow_dissect_hash(const struct sk_buff *skb,
                           struct flow_dissector *flow_dissector,
                           void *target_container)
{
        struct flow_dissector_key_hash *key;

        if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_HASH))
                return;

        key = skb_flow_dissector_target(flow_dissector,
                                        FLOW_DISSECTOR_KEY_HASH,
                                        target_container);

        key->hash = skb_get_hash_raw(skb);
}
EXPORT_SYMBOL(skb_flow_dissect_hash);

static enum flow_dissect_ret
__skb_flow_dissect_mpls(const struct sk_buff *skb,
                        struct flow_dissector *flow_dissector,
                        void *target_container, const void *data, int nhoff,
                        int hlen, int lse_index, bool *entropy_label)
{
        struct mpls_label *hdr, _hdr;
        u32 entry, label, bos;

        if (!dissector_uses_key(flow_dissector,
                                FLOW_DISSECTOR_KEY_MPLS_ENTROPY) &&
            !dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS))
                return FLOW_DISSECT_RET_OUT_GOOD;

        if (lse_index >= FLOW_DIS_MPLS_MAX)
                return FLOW_DISSECT_RET_OUT_GOOD;

        hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
                                   hlen, &_hdr);
        if (!hdr)
                return FLOW_DISSECT_RET_OUT_BAD;

        entry = ntohl(hdr->entry);
        label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
        bos = (entry & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT;

        if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS)) {
                struct flow_dissector_key_mpls *key_mpls;
                struct flow_dissector_mpls_lse *lse;

                key_mpls = skb_flow_dissector_target(flow_dissector,
                                                     FLOW_DISSECTOR_KEY_MPLS,
                                                     target_container);
                lse = &key_mpls->ls[lse_index];

                lse->mpls_ttl = (entry & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT;
                lse->mpls_bos = bos;
                lse->mpls_tc = (entry & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT;
                lse->mpls_label = label;
                dissector_set_mpls_lse(key_mpls, lse_index);
        }

        if (*entropy_label &&
            dissector_uses_key(flow_dissector,
                               FLOW_DISSECTOR_KEY_MPLS_ENTROPY)) {
                struct flow_dissector_key_keyid *key_keyid;

                key_keyid = skb_flow_dissector_target(flow_dissector,
                                                      FLOW_DISSECTOR_KEY_MPLS_ENTROPY,
                                                      target_container);
                key_keyid->keyid = cpu_to_be32(label);
        }

        *entropy_label = label == MPLS_LABEL_ENTROPY;

        return bos ? FLOW_DISSECT_RET_OUT_GOOD : FLOW_DISSECT_RET_PROTO_AGAIN;
}

static enum flow_dissect_ret
__skb_flow_dissect_arp(const struct sk_buff *skb,
                       struct flow_dissector *flow_dissector,
                       void *target_container, const void *data,
                       int nhoff, int hlen)
{
        struct flow_dissector_key_arp *key_arp;
        struct {
                unsigned char ar_sha[ETH_ALEN];
                unsigned char ar_sip[4];
                unsigned char ar_tha[ETH_ALEN];
                unsigned char ar_tip[4];
        } *arp_eth, _arp_eth;
        const struct arphdr *arp;
        struct arphdr _arp;

        if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ARP))
                return FLOW_DISSECT_RET_OUT_GOOD;

        arp = __skb_header_pointer(skb, nhoff, sizeof(_arp), data,
                                   hlen, &_arp);
        if (!arp)
                return FLOW_DISSECT_RET_OUT_BAD;

        if (arp->ar_hrd != htons(ARPHRD_ETHER) ||
            arp->ar_pro != htons(ETH_P_IP) ||
            arp->ar_hln != ETH_ALEN ||
            arp->ar_pln != 4 ||
            (arp->ar_op != htons(ARPOP_REPLY) &&
             arp->ar_op != htons(ARPOP_REQUEST)))
                return FLOW_DISSECT_RET_OUT_BAD;

        arp_eth = __skb_header_pointer(skb, nhoff + sizeof(_arp),
                                       sizeof(_arp_eth), data,
                                       hlen, &_arp_eth);
        if (!arp_eth)
                return FLOW_DISSECT_RET_OUT_BAD;

        key_arp = skb_flow_dissector_target(flow_dissector,
                                            FLOW_DISSECTOR_KEY_ARP,
                                            target_container);

        memcpy(&key_arp->sip, arp_eth->ar_sip, sizeof(key_arp->sip));
        memcpy(&key_arp->tip, arp_eth->ar_tip, sizeof(key_arp->tip));

        /* Only store the lower byte of the opcode;
         * this covers ARPOP_REPLY and ARPOP_REQUEST.
         */
        key_arp->op = ntohs(arp->ar_op) & 0xff;

        ether_addr_copy(key_arp->sha, arp_eth->ar_sha);
        ether_addr_copy(key_arp->tha, arp_eth->ar_tha);

        return FLOW_DISSECT_RET_OUT_GOOD;
}

static enum flow_dissect_ret
__skb_flow_dissect_cfm(const struct sk_buff *skb,
                       struct flow_dissector *flow_dissector,
                       void *target_container, const void *data,
                       int nhoff, int hlen)
{
        struct flow_dissector_key_cfm *key, *hdr, _hdr;

        if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_CFM))
                return FLOW_DISSECT_RET_OUT_GOOD;

        hdr = __skb_header_pointer(skb, nhoff, sizeof(*key), data, hlen, &_hdr);
        if (!hdr)
                return FLOW_DISSECT_RET_OUT_BAD;

        key = skb_flow_dissector_target(flow_dissector, FLOW_DISSECTOR_KEY_CFM,
                                        target_container);

        key->mdl_ver = hdr->mdl_ver;
        key->opcode = hdr->opcode;

        return FLOW_DISSECT_RET_OUT_GOOD;
}

static enum flow_dissect_ret
__skb_flow_dissect_gre(const struct sk_buff *skb,
                       struct flow_dissector_key_control *key_control,
                       struct flow_dissector *flow_dissector,
                       void *target_container, const void *data,
                       __be16 *p_proto, int *p_nhoff, int *p_hlen,
                       unsigned int flags)
{
        struct flow_dissector_key_keyid *key_keyid;
        struct gre_base_hdr *hdr, _hdr;
        int offset = 0;
        u16 gre_ver;

        hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr),
                                   data, *p_hlen, &_hdr);
        if (!hdr)
                return FLOW_DISSECT_RET_OUT_BAD;

        /* Only look inside GRE without routing */
        if (hdr->flags & GRE_ROUTING)
                return FLOW_DISSECT_RET_OUT_GOOD;

        /* Only look inside GRE for version 0 and 1 */
        gre_ver = ntohs(hdr->flags & GRE_VERSION);
        if (gre_ver > 1)
                return FLOW_DISSECT_RET_OUT_GOOD;

        *p_proto = hdr->protocol;
        if (gre_ver) {
                /* Version1 must be PPTP, and check the flags */
                if (!(*p_proto == GRE_PROTO_PPP && (hdr->flags & GRE_KEY)))
                        return FLOW_DISSECT_RET_OUT_GOOD;
        }

        offset += sizeof(struct gre_base_hdr);

        if (hdr->flags & GRE_CSUM)
                offset += sizeof_field(struct gre_full_hdr, csum) +
                          sizeof_field(struct gre_full_hdr, reserved1);

        if (hdr->flags & GRE_KEY) {
                const __be32 *keyid;
                __be32 _keyid;

                keyid = __skb_header_pointer(skb, *p_nhoff + offset,
                                             sizeof(_keyid),
                                             data, *p_hlen, &_keyid);
                if (!keyid)
                        return FLOW_DISSECT_RET_OUT_BAD;

                if (dissector_uses_key(flow_dissector,
                                       FLOW_DISSECTOR_KEY_GRE_KEYID)) {
                        key_keyid = skb_flow_dissector_target(flow_dissector,
                                                              FLOW_DISSECTOR_KEY_GRE_KEYID,
                                                              target_container);
                        if (gre_ver == 0)
                                key_keyid->keyid = *keyid;
                        else
                                key_keyid->keyid = *keyid & GRE_PPTP_KEY_MASK;
                }
                offset += sizeof_field(struct gre_full_hdr, key);
        }

        if (hdr->flags & GRE_SEQ)
                offset += sizeof_field(struct pptp_gre_header, seq);

        if (gre_ver == 0) {
                if (*p_proto == htons(ETH_P_TEB)) {
                        const struct ethhdr *eth;
                        struct ethhdr _eth;

                        eth = __skb_header_pointer(skb, *p_nhoff + offset,
                                                   sizeof(_eth),
                                                   data, *p_hlen, &_eth);
                        if (!eth)
                                return FLOW_DISSECT_RET_OUT_BAD;
                        *p_proto = eth->h_proto;
                        offset += sizeof(*eth);

                        /* Cap headers that we access via pointers at the
                         * end of the Ethernet header as our maximum alignment
                         * at that point is only 2 bytes.
                         */
                        if (NET_IP_ALIGN)
                                *p_hlen = *p_nhoff + offset;
                }
        } else { /* version 1, must be PPTP */
                u8 _ppp_hdr[PPP_HDRLEN];
                u8 *ppp_hdr;

                if (hdr->flags & GRE_ACK)
                        offset += sizeof_field(struct pptp_gre_header, ack);

                ppp_hdr = __skb_header_pointer(skb, *p_nhoff + offset,
                                               sizeof(_ppp_hdr),
                                               data, *p_hlen, _ppp_hdr);
                if (!ppp_hdr)
                        return FLOW_DISSECT_RET_OUT_BAD;

                switch (PPP_PROTOCOL(ppp_hdr)) {
                case PPP_IP:
                        *p_proto = htons(ETH_P_IP);
                        break;
                case PPP_IPV6:
                        *p_proto = htons(ETH_P_IPV6);
                        break;
                default:
                        /* Could probably catch some more like MPLS */
                        break;
                }

                offset += PPP_HDRLEN;
        }

        *p_nhoff += offset;
        key_control->flags |= FLOW_DIS_ENCAPSULATION;
        if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
                return FLOW_DISSECT_RET_OUT_GOOD;

        return FLOW_DISSECT_RET_PROTO_AGAIN;
}

/**
 * __skb_flow_dissect_batadv() - dissect batman-adv header
 * @skb: sk_buff to with the batman-adv header
 * @key_control: flow dissectors control key
 * @data: raw buffer pointer to the packet, if NULL use skb->data
 * @p_proto: pointer used to update the protocol to process next
 * @p_nhoff: pointer used to update inner network header offset
 * @hlen: packet header length
 * @flags: any combination of FLOW_DISSECTOR_F_*
 *
 * ETH_P_BATMAN packets are tried to be dissected. Only
 * &struct batadv_unicast packets are actually processed because they contain an
 * inner ethernet header and are usually followed by actual network header. This
 * allows the flow dissector to continue processing the packet.
 *
 * Return: FLOW_DISSECT_RET_PROTO_AGAIN when &struct batadv_unicast was found,
 *  FLOW_DISSECT_RET_OUT_GOOD when dissector should stop after encapsulation,
 *  otherwise FLOW_DISSECT_RET_OUT_BAD
 */
static enum flow_dissect_ret
__skb_flow_dissect_batadv(const struct sk_buff *skb,
                          struct flow_dissector_key_control *key_control,
                          const void *data, __be16 *p_proto, int *p_nhoff,
                          int hlen, unsigned int flags)
{
        struct {
                struct batadv_unicast_packet batadv_unicast;
                struct ethhdr eth;
        } *hdr, _hdr;

        hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr), data, hlen,
                                   &_hdr);
        if (!hdr)
                return FLOW_DISSECT_RET_OUT_BAD;

        if (hdr->batadv_unicast.version != BATADV_COMPAT_VERSION)
                return FLOW_DISSECT_RET_OUT_BAD;

        if (hdr->batadv_unicast.packet_type != BATADV_UNICAST)
                return FLOW_DISSECT_RET_OUT_BAD;

        *p_proto = hdr->eth.h_proto;
        *p_nhoff += sizeof(*hdr);

        key_control->flags |= FLOW_DIS_ENCAPSULATION;
        if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
                return FLOW_DISSECT_RET_OUT_GOOD;

        return FLOW_DISSECT_RET_PROTO_AGAIN;
}

static void
__skb_flow_dissect_tcp(const struct sk_buff *skb,
                       struct flow_dissector *flow_dissector,
                       void *target_container, const void *data,
                       int thoff, int hlen)
{
        struct flow_dissector_key_tcp *key_tcp;
        struct tcphdr *th, _th;

        if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_TCP))
                return;

        th = __skb_header_pointer(skb, thoff, sizeof(_th), data, hlen, &_th);
        if (!th)
                return;

        if (unlikely(__tcp_hdrlen(th) < sizeof(_th)))
                return;

        key_tcp = skb_flow_dissector_target(flow_dissector,
                                            FLOW_DISSECTOR_KEY_TCP,
                                            target_container);
        key_tcp->flags = (*(__be16 *) &tcp_flag_word(th) & htons(0x0FFF));
}

static void
__skb_flow_dissect_ports(const struct sk_buff *skb,
                         struct flow_dissector *flow_dissector,
                         void *target_container, const void *data,
                         int nhoff, u8 ip_proto, int hlen)
{
        struct flow_dissector_key_ports_range *key_ports_range = NULL;
        struct flow_dissector_key_ports *key_ports = NULL;
        __be32 ports;

        if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS))
                key_ports = skb_flow_dissector_target(flow_dissector,
                                                      FLOW_DISSECTOR_KEY_PORTS,
                                                      target_container);

        if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS_RANGE))
                key_ports_range = skb_flow_dissector_target(flow_dissector,
                                                            FLOW_DISSECTOR_KEY_PORTS_RANGE,
                                                            target_container);

        if (!key_ports && !key_ports_range)
                return;

        ports = skb_flow_get_ports(skb, nhoff, ip_proto, data, hlen);

        if (key_ports)
                key_ports->ports = ports;

        if (key_ports_range)
                key_ports_range->tp.ports = ports;
}

static void
__skb_flow_dissect_ipv4(const struct sk_buff *skb,
                        struct flow_dissector *flow_dissector,
                        void *target_container, const void *data,
                        const struct iphdr *iph)
{
        struct flow_dissector_key_ip *key_ip;

        if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
                return;

        key_ip = skb_flow_dissector_target(flow_dissector,
                                           FLOW_DISSECTOR_KEY_IP,
                                           target_container);
        key_ip->tos = iph->tos;
        key_ip->ttl = iph->ttl;
}

static void
__skb_flow_dissect_ipv6(const struct sk_buff *skb,
                        struct flow_dissector *flow_dissector,
                        void *target_container, const void *data,
                        const struct ipv6hdr *iph)
{
        struct flow_dissector_key_ip *key_ip;

        if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
                return;

        key_ip = skb_flow_dissector_target(flow_dissector,
                                           FLOW_DISSECTOR_KEY_IP,
                                           target_container);
        key_ip->tos = ipv6_get_dsfield(iph);
        key_ip->ttl = iph->hop_limit;
}

/* Maximum number of protocol headers that can be parsed in
 * __skb_flow_dissect
 */
#define MAX_FLOW_DISSECT_HDRS   15

static bool skb_flow_dissect_allowed(int *num_hdrs)
{
        ++*num_hdrs;

        return (*num_hdrs <= MAX_FLOW_DISSECT_HDRS);
}

static void __skb_flow_bpf_to_target(const struct bpf_flow_keys *flow_keys,
                                     struct flow_dissector *flow_dissector,
                                     void *target_container)
{
        struct flow_dissector_key_ports_range *key_ports_range = NULL;
        struct flow_dissector_key_ports *key_ports = NULL;
        struct flow_dissector_key_control *key_control;
        struct flow_dissector_key_basic *key_basic;
        struct flow_dissector_key_addrs *key_addrs;
        struct flow_dissector_key_tags *key_tags;

        key_control = skb_flow_dissector_target(flow_dissector,
                                                FLOW_DISSECTOR_KEY_CONTROL,
                                                target_container);
        key_control->thoff = flow_keys->thoff;
        if (flow_keys->is_frag)
                key_control->flags |= FLOW_DIS_IS_FRAGMENT;
        if (flow_keys->is_first_frag)
                key_control->flags |= FLOW_DIS_FIRST_FRAG;
        if (flow_keys->is_encap)
                key_control->flags |= FLOW_DIS_ENCAPSULATION;

        key_basic = skb_flow_dissector_target(flow_dissector,
                                              FLOW_DISSECTOR_KEY_BASIC,
                                              target_container);
        key_basic->n_proto = flow_keys->n_proto;
        key_basic->ip_proto = flow_keys->ip_proto;

        if (flow_keys->addr_proto == ETH_P_IP &&
            dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
                key_addrs = skb_flow_dissector_target(flow_dissector,
                                                      FLOW_DISSECTOR_KEY_IPV4_ADDRS,
                                                      target_container);
                key_addrs->v4addrs.src = flow_keys->ipv4_src;
                key_addrs->v4addrs.dst = flow_keys->ipv4_dst;
                key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
        } else if (flow_keys->addr_proto == ETH_P_IPV6 &&
                   dissector_uses_key(flow_dissector,
                                      FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
                key_addrs = skb_flow_dissector_target(flow_dissector,
                                                      FLOW_DISSECTOR_KEY_IPV6_ADDRS,
                                                      target_container);
                memcpy(&key_addrs->v6addrs.src, &flow_keys->ipv6_src,
                       sizeof(key_addrs->v6addrs.src));
                memcpy(&key_addrs->v6addrs.dst, &flow_keys->ipv6_dst,
                       sizeof(key_addrs->v6addrs.dst));
                key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
        }

        if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS)) {
                key_ports = skb_flow_dissector_target(flow_dissector,
                                                      FLOW_DISSECTOR_KEY_PORTS,
                                                      target_container);
                key_ports->src = flow_keys->sport;
                key_ports->dst = flow_keys->dport;
        }
        if (dissector_uses_key(flow_dissector,
                               FLOW_DISSECTOR_KEY_PORTS_RANGE)) {
                key_ports_range = skb_flow_dissector_target(flow_dissector,
                                                            FLOW_DISSECTOR_KEY_PORTS_RANGE,
                                                            target_container);
                key_ports_range->tp.src = flow_keys->sport;
                key_ports_range->tp.dst = flow_keys->dport;
        }

        if (dissector_uses_key(flow_dissector,
                               FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
                key_tags = skb_flow_dissector_target(flow_dissector,
                                                     FLOW_DISSECTOR_KEY_FLOW_LABEL,
                                                     target_container);
                key_tags->flow_label = ntohl(flow_keys->flow_label);
        }
}

u32 bpf_flow_dissect(struct bpf_prog *prog, struct bpf_flow_dissector *ctx,
                     __be16 proto, int nhoff, int hlen, unsigned int flags)
{
        struct bpf_flow_keys *flow_keys = ctx->flow_keys;
        u32 result;

        /* Pass parameters to the BPF program */
        memset(flow_keys, 0, sizeof(*flow_keys));
        flow_keys->n_proto = proto;
        flow_keys->nhoff = nhoff;
        flow_keys->thoff = flow_keys->nhoff;

        BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG !=
                     (int)FLOW_DISSECTOR_F_PARSE_1ST_FRAG);
        BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL !=
                     (int)FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
        BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_STOP_AT_ENCAP !=
                     (int)FLOW_DISSECTOR_F_STOP_AT_ENCAP);
        flow_keys->flags = flags;

        result = bpf_prog_run_pin_on_cpu(prog, ctx);

        flow_keys->nhoff = clamp_t(u16, flow_keys->nhoff, nhoff, hlen);
        flow_keys->thoff = clamp_t(u16, flow_keys->thoff,
                                   flow_keys->nhoff, hlen);

        return result;
}

static bool is_pppoe_ses_hdr_valid(const struct pppoe_hdr *hdr)
{
        return hdr->ver == 1 && hdr->type == 1 && hdr->code == 0;
}

/**
 * __skb_flow_dissect - extract the flow_keys struct and return it
 * @net: associated network namespace, derived from @skb if NULL
 * @skb: sk_buff to extract the flow from, can be NULL if the rest are specified
 * @flow_dissector: list of keys to dissect
 * @target_container: target structure to put dissected values into
 * @data: raw buffer pointer to the packet, if NULL use skb->data
 * @proto: protocol for which to get the flow, if @data is NULL use skb->protocol
 * @nhoff: network header offset, if @data is NULL use skb_network_offset(skb)
 * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
 * @flags: flags that control the dissection process, e.g.
 *         FLOW_DISSECTOR_F_STOP_AT_ENCAP.
 *
 * The function will try to retrieve individual keys into target specified
 * by flow_dissector from either the skbuff or a raw buffer specified by the
 * rest parameters.
 *
 * Caller must take care of zeroing target container memory.
 */
bool __skb_flow_dissect(const struct net *net,
                        const struct sk_buff *skb,
                        struct flow_dissector *flow_dissector,
                        void *target_container, const void *data,
                        __be16 proto, int nhoff, int hlen, unsigned int flags)
{
        struct flow_dissector_key_control *key_control;
        struct flow_dissector_key_basic *key_basic;
        struct flow_dissector_key_addrs *key_addrs;
        struct flow_dissector_key_tags *key_tags;
        struct flow_dissector_key_vlan *key_vlan;
        enum flow_dissect_ret fdret;
        enum flow_dissector_key_id dissector_vlan = FLOW_DISSECTOR_KEY_MAX;
        bool mpls_el = false;
        int mpls_lse = 0;
        int num_hdrs = 0;
        u8 ip_proto = 0;
        bool ret;

        if (!data) {
                data = skb->data;
                proto = skb_vlan_tag_present(skb) ?
                         skb->vlan_proto : skb->protocol;
                nhoff = skb_network_offset(skb);
                hlen = skb_headlen(skb);
#if IS_ENABLED(CONFIG_NET_DSA)
                if (unlikely(skb->dev && netdev_uses_dsa(skb->dev) &&
                             proto == htons(ETH_P_XDSA))) {
                        struct metadata_dst *md_dst = skb_metadata_dst(skb);
                        const struct dsa_device_ops *ops;
                        int offset = 0;

                        ops = skb->dev->dsa_ptr->tag_ops;
                        /* Only DSA header taggers break flow dissection */
                        if (ops->needed_headroom &&
                            (!md_dst || md_dst->type != METADATA_HW_PORT_MUX)) {
                                if (ops->flow_dissect)
                                        ops->flow_dissect(skb, &proto, &offset);
                                else
                                        dsa_tag_generic_flow_dissect(skb,
                                                                     &proto,
                                                                     &offset);
                                hlen -= offset;
                                nhoff += offset;
                        }
                }
#endif
        }

        /* It is ensured by skb_flow_dissector_init() that control key will
         * be always present.
         */
        key_control = skb_flow_dissector_target(flow_dissector,
                                                FLOW_DISSECTOR_KEY_CONTROL,
                                                target_container);

        /* It is ensured by skb_flow_dissector_init() that basic key will
         * be always present.
         */
        key_basic = skb_flow_dissector_target(flow_dissector,
                                              FLOW_DISSECTOR_KEY_BASIC,
                                              target_container);

        rcu_read_lock();

        if (skb) {
                if (!net) {
                        if (skb->dev)
                                net = dev_net_rcu(skb->dev);
                        else if (skb->sk)
                                net = sock_net(skb->sk);
                }
        }

        DEBUG_NET_WARN_ON_ONCE(!net);
        if (net) {
                enum netns_bpf_attach_type type = NETNS_BPF_FLOW_DISSECTOR;
                struct bpf_prog_array *run_array;

                run_array = rcu_dereference(init_net.bpf.run_array[type]);
                if (!run_array)
                        run_array = rcu_dereference(net->bpf.run_array[type]);

                if (run_array) {
                        struct bpf_flow_keys flow_keys;
                        struct bpf_flow_dissector ctx = {
                                .flow_keys = &flow_keys,
                                .data = data,
                                .data_end = data + hlen,
                        };
                        __be16 n_proto = proto;
                        struct bpf_prog *prog;
                        u32 result;

                        if (skb) {
                                ctx.skb = skb;
                                /* we can't use 'proto' in the skb case
                                 * because it might be set to skb->vlan_proto
                                 * which has been pulled from the data
                                 */
                                n_proto = skb->protocol;
                        }

                        prog = READ_ONCE(run_array->items[0].prog);
                        result = bpf_flow_dissect(prog, &ctx, n_proto, nhoff,
                                                  hlen, flags);
                        if (result != BPF_FLOW_DISSECTOR_CONTINUE) {
                                __skb_flow_bpf_to_target(&flow_keys, flow_dissector,
                                                         target_container);
                                rcu_read_unlock();
                                return result == BPF_OK;
                        }
                }
        }

        rcu_read_unlock();

        if (dissector_uses_key(flow_dissector,
                               FLOW_DISSECTOR_KEY_ETH_ADDRS)) {
                struct ethhdr *eth = eth_hdr(skb);
                struct flow_dissector_key_eth_addrs *key_eth_addrs;

                key_eth_addrs = skb_flow_dissector_target(flow_dissector,
                                                          FLOW_DISSECTOR_KEY_ETH_ADDRS,
                                                          target_container);
                memcpy(key_eth_addrs, eth, sizeof(*key_eth_addrs));
        }

        if (dissector_uses_key(flow_dissector,
                               FLOW_DISSECTOR_KEY_NUM_OF_VLANS)) {
                struct flow_dissector_key_num_of_vlans *key_num_of_vlans;

                key_num_of_vlans = skb_flow_dissector_target(flow_dissector,
                                                             FLOW_DISSECTOR_KEY_NUM_OF_VLANS,
                                                             target_container);
                key_num_of_vlans->num_of_vlans = 0;
        }

proto_again:
        fdret = FLOW_DISSECT_RET_CONTINUE;

        switch (proto) {
        case htons(ETH_P_IP): {
                const struct iphdr *iph;
                struct iphdr _iph;

                iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
                if (!iph || iph->ihl < 5) {
                        fdret = FLOW_DISSECT_RET_OUT_BAD;
                        break;
                }

                nhoff += iph->ihl * 4;

                ip_proto = iph->protocol;

                if (dissector_uses_key(flow_dissector,
                                       FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
                        key_addrs = skb_flow_dissector_target(flow_dissector,
                                                              FLOW_DISSECTOR_KEY_IPV4_ADDRS,
                                                              target_container);

                        memcpy(&key_addrs->v4addrs.src, &iph->saddr,
                               sizeof(key_addrs->v4addrs.src));
                        memcpy(&key_addrs->v4addrs.dst, &iph->daddr,
                               sizeof(key_addrs->v4addrs.dst));
                        key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
                }

                __skb_flow_dissect_ipv4(skb, flow_dissector,
                                        target_container, data, iph);

                if (ip_is_fragment(iph)) {
                        key_control->flags |= FLOW_DIS_IS_FRAGMENT;

                        if (iph->frag_off & htons(IP_OFFSET)) {
                                fdret = FLOW_DISSECT_RET_OUT_GOOD;
                                break;
                        } else {
                                key_control->flags |= FLOW_DIS_FIRST_FRAG;
                                if (!(flags &
                                      FLOW_DISSECTOR_F_PARSE_1ST_FRAG)) {
                                        fdret = FLOW_DISSECT_RET_OUT_GOOD;
                                        break;
                                }
                        }
                }

                break;
        }
        case htons(ETH_P_IPV6): {
                const struct ipv6hdr *iph;
                struct ipv6hdr _iph;

                iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
                if (!iph) {
                        fdret = FLOW_DISSECT_RET_OUT_BAD;
                        break;
                }

                ip_proto = iph->nexthdr;
                nhoff += sizeof(struct ipv6hdr);

                if (dissector_uses_key(flow_dissector,
                                       FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
                        key_addrs = skb_flow_dissector_target(flow_dissector,
                                                              FLOW_DISSECTOR_KEY_IPV6_ADDRS,
                                                              target_container);

                        memcpy(&key_addrs->v6addrs.src, &iph->saddr,
                               sizeof(key_addrs->v6addrs.src));
                        memcpy(&key_addrs->v6addrs.dst, &iph->daddr,
                               sizeof(key_addrs->v6addrs.dst));
                        key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
                }

                if ((dissector_uses_key(flow_dissector,
                                        FLOW_DISSECTOR_KEY_FLOW_LABEL) ||
                     (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL)) &&
                    ip6_flowlabel(iph)) {
                        __be32 flow_label = ip6_flowlabel(iph);

                        if (dissector_uses_key(flow_dissector,
                                               FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
                                key_tags = skb_flow_dissector_target(flow_dissector,
                                                                     FLOW_DISSECTOR_KEY_FLOW_LABEL,
                                                                     target_container);
                                key_tags->flow_label = ntohl(flow_label);
                        }
                        if (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL) {
                                fdret = FLOW_DISSECT_RET_OUT_GOOD;
                                break;
                        }
                }

                __skb_flow_dissect_ipv6(skb, flow_dissector,
                                        target_container, data, iph);

                break;
        }
        case htons(ETH_P_8021AD):
        case htons(ETH_P_8021Q): {
                const struct vlan_hdr *vlan = NULL;
                struct vlan_hdr _vlan;
                __be16 saved_vlan_tpid = proto;

                if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX &&
                    skb && skb_vlan_tag_present(skb)) {
                        proto = skb->protocol;
                } else {
                        vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan),
                                                    data, hlen, &_vlan);
                        if (!vlan) {
                                fdret = FLOW_DISSECT_RET_OUT_BAD;
                                break;
                        }

                        proto = vlan->h_vlan_encapsulated_proto;
                        nhoff += sizeof(*vlan);
                }

                if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_NUM_OF_VLANS) &&
                    !(key_control->flags & FLOW_DIS_ENCAPSULATION)) {
                        struct flow_dissector_key_num_of_vlans *key_nvs;

                        key_nvs = skb_flow_dissector_target(flow_dissector,
                                                            FLOW_DISSECTOR_KEY_NUM_OF_VLANS,
                                                            target_container);
                        key_nvs->num_of_vlans++;
                }

                if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX) {
                        dissector_vlan = FLOW_DISSECTOR_KEY_VLAN;
                } else if (dissector_vlan == FLOW_DISSECTOR_KEY_VLAN) {
                        dissector_vlan = FLOW_DISSECTOR_KEY_CVLAN;
                } else {
                        fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
                        break;
                }

                if (dissector_uses_key(flow_dissector, dissector_vlan)) {
                        key_vlan = skb_flow_dissector_target(flow_dissector,
                                                             dissector_vlan,
                                                             target_container);

                        if (!vlan) {
                                key_vlan->vlan_id = skb_vlan_tag_get_id(skb);
                                key_vlan->vlan_priority = skb_vlan_tag_get_prio(skb);
                        } else {
                                key_vlan->vlan_id = ntohs(vlan->h_vlan_TCI) &
                                        VLAN_VID_MASK;
                                key_vlan->vlan_priority =
                                        (ntohs(vlan->h_vlan_TCI) &
                                         VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
                        }
                        key_vlan->vlan_tpid = saved_vlan_tpid;
                        key_vlan->vlan_eth_type = proto;
                }

                fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
                break;
        }
        case htons(ETH_P_PPP_SES): {
                struct {
                        struct pppoe_hdr hdr;
                        __be16 proto;
                } *hdr, _hdr;
                u16 ppp_proto;

                hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
                if (!hdr) {
                        fdret = FLOW_DISSECT_RET_OUT_BAD;
                        break;
                }

                if (!is_pppoe_ses_hdr_valid(&hdr->hdr)) {
                        fdret = FLOW_DISSECT_RET_OUT_BAD;
                        break;
                }

                /* least significant bit of the most significant octet
                 * indicates if protocol field was compressed
                 */
                ppp_proto = ntohs(hdr->proto);
                if (ppp_proto & 0x0100) {
                        ppp_proto = ppp_proto >> 8;
                        nhoff += PPPOE_SES_HLEN - 1;
                } else {
                        nhoff += PPPOE_SES_HLEN;
                }

                if (ppp_proto == PPP_IP) {
                        proto = htons(ETH_P_IP);
                        fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
                } else if (ppp_proto == PPP_IPV6) {
                        proto = htons(ETH_P_IPV6);
                        fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
                } else if (ppp_proto == PPP_MPLS_UC) {
                        proto = htons(ETH_P_MPLS_UC);
                        fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
                } else if (ppp_proto == PPP_MPLS_MC) {
                        proto = htons(ETH_P_MPLS_MC);
                        fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
                } else if (ppp_proto_is_valid(ppp_proto)) {
                        fdret = FLOW_DISSECT_RET_OUT_GOOD;
                } else {
                        fdret = FLOW_DISSECT_RET_OUT_BAD;
                        break;
                }

                if (dissector_uses_key(flow_dissector,
                                       FLOW_DISSECTOR_KEY_PPPOE)) {
                        struct flow_dissector_key_pppoe *key_pppoe;

                        key_pppoe = skb_flow_dissector_target(flow_dissector,
                                                              FLOW_DISSECTOR_KEY_PPPOE,
                                                              target_container);
                        key_pppoe->session_id = hdr->hdr.sid;
                        key_pppoe->ppp_proto = htons(ppp_proto);
                        key_pppoe->type = htons(ETH_P_PPP_SES);
                }
                break;
        }
        case htons(ETH_P_TIPC): {
                struct tipc_basic_hdr *hdr, _hdr;

                hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr),
                                           data, hlen, &_hdr);
                if (!hdr) {
                        fdret = FLOW_DISSECT_RET_OUT_BAD;
                        break;
                }

                if (dissector_uses_key(flow_dissector,
                                       FLOW_DISSECTOR_KEY_TIPC)) {
                        key_addrs = skb_flow_dissector_target(flow_dissector,
                                                              FLOW_DISSECTOR_KEY_TIPC,
                                                              target_container);
                        key_addrs->tipckey.key = tipc_hdr_rps_key(hdr);
                        key_control->addr_type = FLOW_DISSECTOR_KEY_TIPC;
                }
                fdret = FLOW_DISSECT_RET_OUT_GOOD;
                break;
        }

        case htons(ETH_P_MPLS_UC):
        case htons(ETH_P_MPLS_MC):
                fdret = __skb_flow_dissect_mpls(skb, flow_dissector,
                                                target_container, data,
                                                nhoff, hlen, mpls_lse,
                                                &mpls_el);
                nhoff += sizeof(struct mpls_label);
                mpls_lse++;
                break;
        case htons(ETH_P_FCOE):
                if ((hlen - nhoff) < FCOE_HEADER_LEN) {
                        fdret = FLOW_DISSECT_RET_OUT_BAD;
                        break;
                }

                nhoff += FCOE_HEADER_LEN;
                fdret = FLOW_DISSECT_RET_OUT_GOOD;
                break;

        case htons(ETH_P_ARP):
        case htons(ETH_P_RARP):
                fdret = __skb_flow_dissect_arp(skb, flow_dissector,
                                               target_container, data,
                                               nhoff, hlen);
                break;

        case htons(ETH_P_BATMAN):
                fdret = __skb_flow_dissect_batadv(skb, key_control, data,
                                                  &proto, &nhoff, hlen, flags);
                break;

        case htons(ETH_P_1588): {
                struct ptp_header *hdr, _hdr;

                hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
                                           hlen, &_hdr);
                if (!hdr) {
                        fdret = FLOW_DISSECT_RET_OUT_BAD;
                        break;
                }

                nhoff += sizeof(struct ptp_header);
                fdret = FLOW_DISSECT_RET_OUT_GOOD;
                break;
        }

        case htons(ETH_P_PRP):
        case htons(ETH_P_HSR): {
                struct hsr_tag *hdr, _hdr;

                hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen,
                                           &_hdr);
                if (!hdr) {
                        fdret = FLOW_DISSECT_RET_OUT_BAD;
                        break;
                }

                proto = hdr->encap_proto;
                nhoff += HSR_HLEN;
                fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
                break;
        }

        case htons(ETH_P_CFM):
                fdret = __skb_flow_dissect_cfm(skb, flow_dissector,
                                               target_container, data,
                                               nhoff, hlen);
                break;

        default:
                fdret = FLOW_DISSECT_RET_OUT_BAD;
                break;
        }

        /* Process result of proto processing */
        switch (fdret) {
        case FLOW_DISSECT_RET_OUT_GOOD:
                goto out_good;
        case FLOW_DISSECT_RET_PROTO_AGAIN:
                if (skb_flow_dissect_allowed(&num_hdrs))
                        goto proto_again;
                goto out_good;
        case FLOW_DISSECT_RET_CONTINUE:
        case FLOW_DISSECT_RET_IPPROTO_AGAIN:
                break;
        case FLOW_DISSECT_RET_OUT_BAD:
        default:
                goto out_bad;
        }

ip_proto_again:
        fdret = FLOW_DISSECT_RET_CONTINUE;

        switch (ip_proto) {
        case IPPROTO_GRE:
                if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
                        fdret = FLOW_DISSECT_RET_OUT_GOOD;
                        break;
                }

                fdret = __skb_flow_dissect_gre(skb, key_control, flow_dissector,
                                               target_container, data,
                                               &proto, &nhoff, &hlen, flags);
                break;

        case NEXTHDR_HOP:
        case NEXTHDR_ROUTING:
        case NEXTHDR_DEST: {
                u8 _opthdr[2], *opthdr;

                if (proto != htons(ETH_P_IPV6))
                        break;

                opthdr = __skb_header_pointer(skb, nhoff, sizeof(_opthdr),
                                              data, hlen, &_opthdr);
                if (!opthdr) {
                        fdret = FLOW_DISSECT_RET_OUT_BAD;
                        break;
                }

                ip_proto = opthdr[0];
                nhoff += (opthdr[1] + 1) << 3;

                fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
                break;
        }
        case NEXTHDR_FRAGMENT: {
                struct frag_hdr _fh, *fh;

                if (proto != htons(ETH_P_IPV6))
                        break;

                fh = __skb_header_pointer(skb, nhoff, sizeof(_fh),
                                          data, hlen, &_fh);

                if (!fh) {
                        fdret = FLOW_DISSECT_RET_OUT_BAD;
                        break;
                }

                key_control->flags |= FLOW_DIS_IS_FRAGMENT;

                nhoff += sizeof(_fh);
                ip_proto = fh->nexthdr;

                if (!(fh->frag_off & htons(IP6_OFFSET))) {
                        key_control->flags |= FLOW_DIS_FIRST_FRAG;
                        if (flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG) {
                                fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
                                break;
                        }
                }

                fdret = FLOW_DISSECT_RET_OUT_GOOD;
                break;
        }
        case IPPROTO_IPIP:
                if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
                        fdret = FLOW_DISSECT_RET_OUT_GOOD;
                        break;
                }

                proto = htons(ETH_P_IP);

                key_control->flags |= FLOW_DIS_ENCAPSULATION;
                if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
                        fdret = FLOW_DISSECT_RET_OUT_GOOD;
                        break;
                }

                fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
                break;

        case IPPROTO_IPV6:
                if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
                        fdret = FLOW_DISSECT_RET_OUT_GOOD;
                        break;
                }

                proto = htons(ETH_P_IPV6);

                key_control->flags |= FLOW_DIS_ENCAPSULATION;
                if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
                        fdret = FLOW_DISSECT_RET_OUT_GOOD;
                        break;
                }

                fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
                break;


        case IPPROTO_MPLS:
                proto = htons(ETH_P_MPLS_UC);
                fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
                break;

        case IPPROTO_TCP:
                __skb_flow_dissect_tcp(skb, flow_dissector, target_container,
                                       data, nhoff, hlen);
                break;

        case IPPROTO_ICMP:
        case IPPROTO_ICMPV6:
                __skb_flow_dissect_icmp(skb, flow_dissector, target_container,
                                        data, nhoff, hlen);
                break;
        case IPPROTO_L2TP:
                __skb_flow_dissect_l2tpv3(skb, flow_dissector, target_container,
                                          data, nhoff, hlen);
                break;
        case IPPROTO_ESP:
                __skb_flow_dissect_esp(skb, flow_dissector, target_container,
                                       data, nhoff, hlen);
                break;
        case IPPROTO_AH:
                __skb_flow_dissect_ah(skb, flow_dissector, target_container,
                                      data, nhoff, hlen);
                break;
        default:
                break;
        }

        if (!(key_control->flags & FLOW_DIS_IS_FRAGMENT))
                __skb_flow_dissect_ports(skb, flow_dissector, target_container,
                                         data, nhoff, ip_proto, hlen);

        /* Process result of IP proto processing */
        switch (fdret) {
        case FLOW_DISSECT_RET_PROTO_AGAIN:
                if (skb_flow_dissect_allowed(&num_hdrs))
                        goto proto_again;
                break;
        case FLOW_DISSECT_RET_IPPROTO_AGAIN:
                if (skb_flow_dissect_allowed(&num_hdrs))
                        goto ip_proto_again;
                break;
        case FLOW_DISSECT_RET_OUT_GOOD:
        case FLOW_DISSECT_RET_CONTINUE:
                break;
        case FLOW_DISSECT_RET_OUT_BAD:
        default:
                goto out_bad;
        }

out_good:
        ret = true;

out:
        key_control->thoff = min_t(u16, nhoff, skb ? skb->len : hlen);
        key_basic->n_proto = proto;
        key_basic->ip_proto = ip_proto;

        return ret;

out_bad:
        ret = false;
        goto out;
}
EXPORT_SYMBOL(__skb_flow_dissect);

static siphash_aligned_key_t hashrnd;
static __always_inline void __flow_hash_secret_init(void)
{
        net_get_random_once(&hashrnd, sizeof(hashrnd));
}

static const void *flow_keys_hash_start(const struct flow_keys *flow)
{
        BUILD_BUG_ON(FLOW_KEYS_HASH_OFFSET % SIPHASH_ALIGNMENT);
        return &flow->FLOW_KEYS_HASH_START_FIELD;
}

static inline size_t flow_keys_hash_length(const struct flow_keys *flow)
{
        size_t diff = FLOW_KEYS_HASH_OFFSET + sizeof(flow->addrs);

        BUILD_BUG_ON((sizeof(*flow) - FLOW_KEYS_HASH_OFFSET) % sizeof(u32));

        switch (flow->control.addr_type) {
        case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
                diff -= sizeof(flow->addrs.v4addrs);
                break;
        case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
                diff -= sizeof(flow->addrs.v6addrs);
                break;
        case FLOW_DISSECTOR_KEY_TIPC:
                diff -= sizeof(flow->addrs.tipckey);
                break;
        }
        return sizeof(*flow) - diff;
}

__be32 flow_get_u32_src(const struct flow_keys *flow)
{
        switch (flow->control.addr_type) {
        case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
                return flow->addrs.v4addrs.src;
        case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
                return (__force __be32)ipv6_addr_hash(
                        &flow->addrs.v6addrs.src);
        case FLOW_DISSECTOR_KEY_TIPC:
                return flow->addrs.tipckey.key;
        default:
                return 0;
        }
}
EXPORT_SYMBOL(flow_get_u32_src);

__be32 flow_get_u32_dst(const struct flow_keys *flow)
{
        switch (flow->control.addr_type) {
        case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
                return flow->addrs.v4addrs.dst;
        case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
                return (__force __be32)ipv6_addr_hash(
                        &flow->addrs.v6addrs.dst);
        default:
                return 0;
        }
}
EXPORT_SYMBOL(flow_get_u32_dst);

/* Sort the source and destination IP and the ports,
 * to have consistent hash within the two directions
 */
static inline void __flow_hash_consistentify(struct flow_keys *keys)
{
        int addr_diff, i;

        switch (keys->control.addr_type) {
        case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
                if ((__force u32)keys->addrs.v4addrs.dst <
                    (__force u32)keys->addrs.v4addrs.src)
                        swap(keys->addrs.v4addrs.src, keys->addrs.v4addrs.dst);

                if ((__force u16)keys->ports.dst <
                    (__force u16)keys->ports.src) {
                        swap(keys->ports.src, keys->ports.dst);
                }
                break;
        case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
                addr_diff = memcmp(&keys->addrs.v6addrs.dst,
                                   &keys->addrs.v6addrs.src,
                                   sizeof(keys->addrs.v6addrs.dst));
                if (addr_diff < 0) {
                        for (i = 0; i < 4; i++)
                                swap(keys->addrs.v6addrs.src.s6_addr32[i],
                                     keys->addrs.v6addrs.dst.s6_addr32[i]);
                }
                if ((__force u16)keys->ports.dst <
                    (__force u16)keys->ports.src) {
                        swap(keys->ports.src, keys->ports.dst);
                }
                break;
        }
}

static inline u32 __flow_hash_from_keys(struct flow_keys *keys,
                                        const siphash_key_t *keyval)
{
        u32 hash;

        __flow_hash_consistentify(keys);

        hash = siphash(flow_keys_hash_start(keys),
                       flow_keys_hash_length(keys), keyval);
        if (!hash)
                hash = 1;

        return hash;
}

u32 flow_hash_from_keys(struct flow_keys *keys)
{
        __flow_hash_secret_init();
        return __flow_hash_from_keys(keys, &hashrnd);
}
EXPORT_SYMBOL(flow_hash_from_keys);

u32 flow_hash_from_keys_seed(struct flow_keys *keys,
                             const siphash_key_t *keyval)
{
        return __flow_hash_from_keys(keys, keyval);
}
EXPORT_SYMBOL(flow_hash_from_keys_seed);

static inline u32 ___skb_get_hash(const struct sk_buff *skb,
                                  struct flow_keys *keys,
                                  const siphash_key_t *keyval)
{
        skb_flow_dissect_flow_keys(skb, keys,
                                   FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);

        return __flow_hash_from_keys(keys, keyval);
}

struct _flow_keys_digest_data {
        __be16  n_proto;
        u8      ip_proto;
        u8      padding;
        __be32  ports;
        __be32  src;
        __be32  dst;
};

void make_flow_keys_digest(struct flow_keys_digest *digest,
                           const struct flow_keys *flow)
{
        struct _flow_keys_digest_data *data =
            (struct _flow_keys_digest_data *)digest;

        BUILD_BUG_ON(sizeof(*data) > sizeof(*digest));

        memset(digest, 0, sizeof(*digest));

        data->n_proto = flow->basic.n_proto;
        data->ip_proto = flow->basic.ip_proto;
        data->ports = flow->ports.ports;
        data->src = flow->addrs.v4addrs.src;
        data->dst = flow->addrs.v4addrs.dst;
}
EXPORT_SYMBOL(make_flow_keys_digest);

static struct flow_dissector flow_keys_dissector_symmetric __read_mostly;

u32 __skb_get_hash_symmetric_net(const struct net *net, const struct sk_buff *skb)
{
        struct flow_keys keys;

        __flow_hash_secret_init();

        memset(&keys, 0, sizeof(keys));
        __skb_flow_dissect(net, skb, &flow_keys_dissector_symmetric,
                           &keys, NULL, 0, 0, 0, 0);

        return __flow_hash_from_keys(&keys, &hashrnd);
}
EXPORT_SYMBOL_GPL(__skb_get_hash_symmetric_net);

/**
 * __skb_get_hash_net: calculate a flow hash
 * @net: associated network namespace, derived from @skb if NULL
 * @skb: sk_buff to calculate flow hash from
 *
 * This function calculates a flow hash based on src/dst addresses
 * and src/dst port numbers.  Sets hash in skb to non-zero hash value
 * on success, zero indicates no valid hash.  Also, sets l4_hash in skb
 * if hash is a canonical 4-tuple hash over transport ports.
 */
void __skb_get_hash_net(const struct net *net, struct sk_buff *skb)
{
        struct flow_keys keys;
        u32 hash;

        memset(&keys, 0, sizeof(keys));

        __skb_flow_dissect(net, skb, &flow_keys_dissector,
                           &keys, NULL, 0, 0, 0,
                           FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);

        __flow_hash_secret_init();

        hash = __flow_hash_from_keys(&keys, &hashrnd);

        __skb_set_sw_hash(skb, hash, flow_keys_have_l4(&keys));
}
EXPORT_SYMBOL(__skb_get_hash_net);

__u32 skb_get_hash_perturb(const struct sk_buff *skb,
                           const siphash_key_t *perturb)
{
        struct flow_keys keys;

        return ___skb_get_hash(skb, &keys, perturb);
}
EXPORT_SYMBOL(skb_get_hash_perturb);

u32 __skb_get_poff(const struct sk_buff *skb, const void *data,
                   const struct flow_keys_basic *keys, int hlen)
{
        u32 poff = keys->control.thoff;

        /* skip L4 headers for fragments after the first */
        if ((keys->control.flags & FLOW_DIS_IS_FRAGMENT) &&
            !(keys->control.flags & FLOW_DIS_FIRST_FRAG))
                return poff;

        switch (keys->basic.ip_proto) {
        case IPPROTO_TCP: {
                /* access doff as u8 to avoid unaligned access */
                const u8 *doff;
                u8 _doff;

                doff = __skb_header_pointer(skb, poff + 12, sizeof(_doff),
                                            data, hlen, &_doff);
                if (!doff)
                        return poff;

                poff += max_t(u32, sizeof(struct tcphdr), (*doff & 0xF0) >> 2);
                break;
        }
        case IPPROTO_UDP:
        case IPPROTO_UDPLITE:
                poff += sizeof(struct udphdr);
                break;
        /* For the rest, we do not really care about header
         * extensions at this point for now.
         */
        case IPPROTO_ICMP:
                poff += sizeof(struct icmphdr);
                break;
        case IPPROTO_ICMPV6:
                poff += sizeof(struct icmp6hdr);
                break;
        case IPPROTO_IGMP:
                poff += sizeof(struct igmphdr);
                break;
        case IPPROTO_DCCP:
                poff += sizeof(struct dccp_hdr);
                break;
        case IPPROTO_SCTP:
                poff += sizeof(struct sctphdr);
                break;
        }

        return poff;
}

/**
 * skb_get_poff - get the offset to the payload
 * @skb: sk_buff to get the payload offset from
 *
 * The function will get the offset to the payload as far as it could
 * be dissected.  The main user is currently BPF, so that we can dynamically
 * truncate packets without needing to push actual payload to the user
 * space and can analyze headers only, instead.
 */
u32 skb_get_poff(const struct sk_buff *skb)
{
        struct flow_keys_basic keys;

        if (!skb_flow_dissect_flow_keys_basic(NULL, skb, &keys,
                                              NULL, 0, 0, 0, 0))
                return 0;

        return __skb_get_poff(skb, skb->data, &keys, skb_headlen(skb));
}

__u32 __get_hash_from_flowi6(const struct flowi6 *fl6, struct flow_keys *keys)
{
        memset(keys, 0, sizeof(*keys));

        memcpy(&keys->addrs.v6addrs.src, &fl6->saddr,
            sizeof(keys->addrs.v6addrs.src));
        memcpy(&keys->addrs.v6addrs.dst, &fl6->daddr,
            sizeof(keys->addrs.v6addrs.dst));
        keys->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
        keys->ports.src = fl6->fl6_sport;
        keys->ports.dst = fl6->fl6_dport;
        keys->keyid.keyid = fl6->fl6_gre_key;
        keys->tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
        keys->basic.ip_proto = fl6->flowi6_proto;

        return flow_hash_from_keys(keys);
}
EXPORT_SYMBOL(__get_hash_from_flowi6);

static const struct flow_dissector_key flow_keys_dissector_keys[] = {
        {
                .key_id = FLOW_DISSECTOR_KEY_CONTROL,
                .offset = offsetof(struct flow_keys, control),
        },
        {
                .key_id = FLOW_DISSECTOR_KEY_BASIC,
                .offset = offsetof(struct flow_keys, basic),
        },
        {
                .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
                .offset = offsetof(struct flow_keys, addrs.v4addrs),
        },
        {
                .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
                .offset = offsetof(struct flow_keys, addrs.v6addrs),
        },
        {
                .key_id = FLOW_DISSECTOR_KEY_TIPC,
                .offset = offsetof(struct flow_keys, addrs.tipckey),
        },
        {
                .key_id = FLOW_DISSECTOR_KEY_PORTS,
                .offset = offsetof(struct flow_keys, ports),
        },
        {
                .key_id = FLOW_DISSECTOR_KEY_VLAN,
                .offset = offsetof(struct flow_keys, vlan),
        },
        {
                .key_id = FLOW_DISSECTOR_KEY_FLOW_LABEL,
                .offset = offsetof(struct flow_keys, tags),
        },
        {
                .key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
                .offset = offsetof(struct flow_keys, keyid),
        },
};

static const struct flow_dissector_key flow_keys_dissector_symmetric_keys[] = {
        {
                .key_id = FLOW_DISSECTOR_KEY_CONTROL,
                .offset = offsetof(struct flow_keys, control),
        },
        {
                .key_id = FLOW_DISSECTOR_KEY_BASIC,
                .offset = offsetof(struct flow_keys, basic),
        },
        {
                .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
                .offset = offsetof(struct flow_keys, addrs.v4addrs),
        },
        {
                .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
                .offset = offsetof(struct flow_keys, addrs.v6addrs),
        },
        {
                .key_id = FLOW_DISSECTOR_KEY_PORTS,
                .offset = offsetof(struct flow_keys, ports),
        },
};

static const struct flow_dissector_key flow_keys_basic_dissector_keys[] = {
        {
                .key_id = FLOW_DISSECTOR_KEY_CONTROL,
                .offset = offsetof(struct flow_keys, control),
        },
        {
                .key_id = FLOW_DISSECTOR_KEY_BASIC,
                .offset = offsetof(struct flow_keys, basic),
        },
};

struct flow_dissector flow_keys_dissector __read_mostly;
EXPORT_SYMBOL(flow_keys_dissector);

struct flow_dissector flow_keys_basic_dissector __read_mostly;
EXPORT_SYMBOL(flow_keys_basic_dissector);

static int __init init_default_flow_dissectors(void)
{
        skb_flow_dissector_init(&flow_keys_dissector,
                                flow_keys_dissector_keys,
                                ARRAY_SIZE(flow_keys_dissector_keys));
        skb_flow_dissector_init(&flow_keys_dissector_symmetric,
                                flow_keys_dissector_symmetric_keys,
                                ARRAY_SIZE(flow_keys_dissector_symmetric_keys));
        skb_flow_dissector_init(&flow_keys_basic_dissector,
                                flow_keys_basic_dissector_keys,
                                ARRAY_SIZE(flow_keys_basic_dissector_keys));
        return 0;
}
core_initcall(init_default_flow_dissectors);