/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1982, 1986, 1991, 1993, 1995
 *      The Regents of the University of California.
 * Copyright (c) 2007-2009 Robert N. M. Watson
 * Copyright (c) 2010-2011 Juniper Networks, Inc.
 * Copyright (c) 2021-2022 Gleb Smirnoff <glebius@FreeBSD.org>
 * All rights reserved.
 *
 * Portions of this software were developed by Robert N. M. Watson under
 * contract to Juniper Networks, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include "opt_ddb.h"
#include "opt_ipsec.h"
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_ratelimit.h"
#include "opt_rss.h"

#include <sys/param.h>
#include <sys/hash.h>
#include <sys/systm.h>
#include <sys/libkern.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/eventhandler.h>
#include <sys/domain.h>
#include <sys/proc.h>
#include <sys/protosw.h>
#include <sys/smp.h>
#include <sys/smr.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sockio.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/refcount.h>
#include <sys/jail.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>

#ifdef DDB
#include <ddb/ddb.h>
#endif

#include <vm/uma.h>
#include <vm/vm.h>

#include <net/if.h>
#include <net/if_var.h>
#include <net/if_private.h>
#include <net/if_types.h>
#include <net/if_llatbl.h>
#include <net/route.h>
#include <net/rss_config.h>
#include <net/vnet.h>

#if defined(INET) || defined(INET6)
#include <netinet/in.h>
#include <netinet/in_pcb.h>
#include <netinet/in_pcb_var.h>
#include <netinet/tcp.h>
#ifdef INET
#include <netinet/in_var.h>
#include <netinet/in_fib.h>
#endif
#include <netinet/ip_var.h>
#ifdef INET6
#include <netinet/ip6.h>
#include <netinet6/in6_pcb.h>
#include <netinet6/in6_var.h>
#include <netinet6/ip6_var.h>
#endif /* INET6 */
#include <net/route/nhop.h>
#endif

#include <netipsec/ipsec_support.h>

#include <security/mac/mac_framework.h>

#define INPCBLBGROUP_SIZMIN     8
#define INPCBLBGROUP_SIZMAX     256

#define INP_FREED       0x00000200      /* Went through in_pcbfree(). */
#define INP_INLBGROUP   0x01000000      /* Inserted into inpcblbgroup. */

/*
 * These configure the range of local port addresses assigned to
 * "unspecified" outgoing connections/packets/whatever.
 */
VNET_DEFINE(int, ipport_lowfirstauto) = IPPORT_RESERVED - 1;    /* 1023 */
VNET_DEFINE(int, ipport_lowlastauto) = IPPORT_RESERVEDSTART;    /* 600 */
VNET_DEFINE(int, ipport_firstauto) = IPPORT_EPHEMERALFIRST;     /* 10000 */
VNET_DEFINE(int, ipport_lastauto) = IPPORT_EPHEMERALLAST;       /* 65535 */
VNET_DEFINE(int, ipport_hifirstauto) = IPPORT_HIFIRSTAUTO;      /* 49152 */
VNET_DEFINE(int, ipport_hilastauto) = IPPORT_HILASTAUTO;        /* 65535 */

/*
 * Reserved ports accessible only to root. There are significant
 * security considerations that must be accounted for when changing these,
 * but the security benefits can be great. Please be careful.
 */
VNET_DEFINE(int, ipport_reservedhigh) = IPPORT_RESERVED - 1;    /* 1023 */
VNET_DEFINE(int, ipport_reservedlow);

/* Enable random ephemeral port allocation by default. */
VNET_DEFINE(int, ipport_randomized) = 1;

#ifdef INET
static struct inpcb     *in_pcblookup_hash_locked(struct inpcbinfo *pcbinfo,
                            struct in_addr faddr, u_int fport_arg,
                            struct in_addr laddr, u_int lport_arg,
                            int lookupflags, uint8_t numa_domain, int fib);

#define RANGECHK(var, min, max) \
        if ((var) < (min)) { (var) = (min); } \
        else if ((var) > (max)) { (var) = (max); }

static int
sysctl_net_ipport_check(SYSCTL_HANDLER_ARGS)
{
        int error;

        error = sysctl_handle_int(oidp, arg1, arg2, req);
        if (error == 0) {
                RANGECHK(V_ipport_lowfirstauto, 1, IPPORT_RESERVED - 1);
                RANGECHK(V_ipport_lowlastauto, 1, IPPORT_RESERVED - 1);
                RANGECHK(V_ipport_firstauto, IPPORT_RESERVED, IPPORT_MAX);
                RANGECHK(V_ipport_lastauto, IPPORT_RESERVED, IPPORT_MAX);
                RANGECHK(V_ipport_hifirstauto, IPPORT_RESERVED, IPPORT_MAX);
                RANGECHK(V_ipport_hilastauto, IPPORT_RESERVED, IPPORT_MAX);
        }
        return (error);
}

#undef RANGECHK

static SYSCTL_NODE(_net_inet_ip, IPPROTO_IP, portrange,
    CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
    "IP Ports");

SYSCTL_PROC(_net_inet_ip_portrange, OID_AUTO, lowfirst,
    CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
    &VNET_NAME(ipport_lowfirstauto), 0, &sysctl_net_ipport_check, "I",
    "");
SYSCTL_PROC(_net_inet_ip_portrange, OID_AUTO, lowlast,
    CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
    &VNET_NAME(ipport_lowlastauto), 0, &sysctl_net_ipport_check, "I",
    "");
SYSCTL_PROC(_net_inet_ip_portrange, OID_AUTO, first,
    CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
    &VNET_NAME(ipport_firstauto), 0, &sysctl_net_ipport_check, "I",
    "");
SYSCTL_PROC(_net_inet_ip_portrange, OID_AUTO, last,
    CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
    &VNET_NAME(ipport_lastauto), 0, &sysctl_net_ipport_check, "I",
    "");
SYSCTL_PROC(_net_inet_ip_portrange, OID_AUTO, hifirst,
    CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
    &VNET_NAME(ipport_hifirstauto), 0, &sysctl_net_ipport_check, "I",
    "");
SYSCTL_PROC(_net_inet_ip_portrange, OID_AUTO, hilast,
    CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
    &VNET_NAME(ipport_hilastauto), 0, &sysctl_net_ipport_check, "I",
    "");
SYSCTL_INT(_net_inet_ip_portrange, OID_AUTO, reservedhigh,
        CTLFLAG_VNET | CTLFLAG_RW | CTLFLAG_SECURE,
        &VNET_NAME(ipport_reservedhigh), 0, "");
SYSCTL_INT(_net_inet_ip_portrange, OID_AUTO, reservedlow,
        CTLFLAG_RW|CTLFLAG_SECURE, &VNET_NAME(ipport_reservedlow), 0, "");
SYSCTL_INT(_net_inet_ip_portrange, OID_AUTO, randomized,
        CTLFLAG_VNET | CTLFLAG_RW,
        &VNET_NAME(ipport_randomized), 0, "Enable random port allocation");

#ifdef RATELIMIT
counter_u64_t rate_limit_new;
counter_u64_t rate_limit_chg;
counter_u64_t rate_limit_active;
counter_u64_t rate_limit_alloc_fail;
counter_u64_t rate_limit_set_ok;

static SYSCTL_NODE(_net_inet_ip, OID_AUTO, rl, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
    "IP Rate Limiting");
SYSCTL_COUNTER_U64(_net_inet_ip_rl, OID_AUTO, active, CTLFLAG_RD,
    &rate_limit_active, "Active rate limited connections");
SYSCTL_COUNTER_U64(_net_inet_ip_rl, OID_AUTO, alloc_fail, CTLFLAG_RD,
   &rate_limit_alloc_fail, "Rate limited connection failures");
SYSCTL_COUNTER_U64(_net_inet_ip_rl, OID_AUTO, set_ok, CTLFLAG_RD,
   &rate_limit_set_ok, "Rate limited setting succeeded");
SYSCTL_COUNTER_U64(_net_inet_ip_rl, OID_AUTO, newrl, CTLFLAG_RD,
   &rate_limit_new, "Total Rate limit new attempts");
SYSCTL_COUNTER_U64(_net_inet_ip_rl, OID_AUTO, chgrl, CTLFLAG_RD,
   &rate_limit_chg, "Total Rate limited change attempts");
#endif /* RATELIMIT */

#endif /* INET */

VNET_DEFINE(uint32_t, in_pcbhashseed);
static void
in_pcbhashseed_init(void)
{

        V_in_pcbhashseed = arc4random();
}
VNET_SYSINIT(in_pcbhashseed_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST,
    in_pcbhashseed_init, NULL);

#ifdef INET
VNET_DEFINE_STATIC(int, connect_inaddr_wild) = 0;
#define V_connect_inaddr_wild   VNET(connect_inaddr_wild)
SYSCTL_INT(_net_inet_ip, OID_AUTO, connect_inaddr_wild,
    CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(connect_inaddr_wild), 0,
    "Allow connecting to INADDR_ANY or INADDR_BROADCAST for connect(2)");
#endif

static void in_pcbremhash(struct inpcb *);

/*
 * in_pcb.c: manage the Protocol Control Blocks.
 *
 * NOTE: It is assumed that most of these functions will be called with
 * the pcbinfo lock held, and often, the inpcb lock held, as these utility
 * functions often modify hash chains or addresses in pcbs.
 */

static struct inpcblbgroup *
in_pcblbgroup_alloc(struct ucred *cred, u_char vflag, uint16_t port,
    const union in_dependaddr *addr, int size, uint8_t numa_domain, int fib)
{
        struct inpcblbgroup *grp;
        size_t bytes;

        bytes = __offsetof(struct inpcblbgroup, il_inp[size]);
        grp = malloc(bytes, M_PCB, M_ZERO | M_NOWAIT);
        if (grp == NULL)
                return (NULL);
        LIST_INIT(&grp->il_pending);
        grp->il_cred = crhold(cred);
        grp->il_vflag = vflag;
        grp->il_lport = port;
        grp->il_numa_domain = numa_domain;
        grp->il_fibnum = fib;
        grp->il_dependladdr = *addr;
        grp->il_inpsiz = size;
        return (grp);
}

static void
in_pcblbgroup_free_deferred(epoch_context_t ctx)
{
        struct inpcblbgroup *grp;

        grp = __containerof(ctx, struct inpcblbgroup, il_epoch_ctx);
        crfree(grp->il_cred);
        free(grp, M_PCB);
}

static void
in_pcblbgroup_free(struct inpcblbgroup *grp)
{
        KASSERT(LIST_EMPTY(&grp->il_pending),
            ("local group %p still has pending inps", grp));

        CK_LIST_REMOVE(grp, il_list);
        NET_EPOCH_CALL(in_pcblbgroup_free_deferred, &grp->il_epoch_ctx);
}

static struct inpcblbgroup *
in_pcblbgroup_find(struct inpcb *inp)
{
        struct inpcbinfo *pcbinfo;
        struct inpcblbgroup *grp;
        struct inpcblbgrouphead *hdr;

        INP_LOCK_ASSERT(inp);

        pcbinfo = inp->inp_pcbinfo;
        INP_HASH_LOCK_ASSERT(pcbinfo);

        hdr = &pcbinfo->ipi_lbgrouphashbase[
            INP_PCBPORTHASH(inp->inp_lport, pcbinfo->ipi_lbgrouphashmask)];
        CK_LIST_FOREACH(grp, hdr, il_list) {
                struct inpcb *inp1;

                for (unsigned int i = 0; i < grp->il_inpcnt; i++) {
                        if (inp == grp->il_inp[i])
                                goto found;
                }
                LIST_FOREACH(inp1, &grp->il_pending, inp_lbgroup_list) {
                        if (inp == inp1)
                                goto found;
                }
        }
found:
        return (grp);
}

static void
in_pcblbgroup_insert(struct inpcblbgroup *grp, struct inpcb *inp)
{
        KASSERT(grp->il_inpcnt < grp->il_inpsiz,
            ("invalid local group size %d and count %d", grp->il_inpsiz,
            grp->il_inpcnt));
        INP_WLOCK_ASSERT(inp);

        if (inp->inp_socket->so_proto->pr_listen != pr_listen_notsupp &&
            !SOLISTENING(inp->inp_socket)) {
                /*
                 * If this is a TCP socket, it should not be visible to lbgroup
                 * lookups until listen() has been called.
                 */
                LIST_INSERT_HEAD(&grp->il_pending, inp, inp_lbgroup_list);
                grp->il_pendcnt++;
        } else {
                grp->il_inp[grp->il_inpcnt] = inp;

                /*
                 * Synchronize with in_pcblookup_lbgroup(): make sure that we
                 * don't expose a null slot to the lookup path.
                 */
                atomic_store_rel_int(&grp->il_inpcnt, grp->il_inpcnt + 1);
        }

        inp->inp_flags |= INP_INLBGROUP;
}

static struct inpcblbgroup *
in_pcblbgroup_resize(struct inpcblbgrouphead *hdr,
    struct inpcblbgroup *old_grp, int size)
{
        struct inpcblbgroup *grp;
        int i;

        grp = in_pcblbgroup_alloc(old_grp->il_cred, old_grp->il_vflag,
            old_grp->il_lport, &old_grp->il_dependladdr, size,
            old_grp->il_numa_domain, old_grp->il_fibnum);
        if (grp == NULL)
                return (NULL);

        KASSERT(old_grp->il_inpcnt < grp->il_inpsiz,
            ("invalid new local group size %d and old local group count %d",
             grp->il_inpsiz, old_grp->il_inpcnt));

        for (i = 0; i < old_grp->il_inpcnt; ++i)
                grp->il_inp[i] = old_grp->il_inp[i];
        grp->il_inpcnt = old_grp->il_inpcnt;
        CK_LIST_INSERT_HEAD(hdr, grp, il_list);
        LIST_SWAP(&old_grp->il_pending, &grp->il_pending, inpcb,
            inp_lbgroup_list);
        grp->il_pendcnt = old_grp->il_pendcnt;
        old_grp->il_pendcnt = 0;
        in_pcblbgroup_free(old_grp);
        return (grp);
}

/*
 * Add PCB to load balance group for SO_REUSEPORT_LB option.
 */
static int
in_pcbinslbgrouphash(struct inpcb *inp, uint8_t numa_domain)
{
        const static struct timeval interval = { 60, 0 };
        static struct timeval lastprint;
        struct inpcbinfo *pcbinfo;
        struct inpcblbgrouphead *hdr;
        struct inpcblbgroup *grp;
        uint32_t idx;
        int fib;

        pcbinfo = inp->inp_pcbinfo;

        INP_WLOCK_ASSERT(inp);
        INP_HASH_WLOCK_ASSERT(pcbinfo);

        fib = (inp->inp_flags & INP_BOUNDFIB) != 0 ?
            inp->inp_inc.inc_fibnum : RT_ALL_FIBS;

#ifdef INET6
        /*
         * Don't allow IPv4 mapped INET6 wild socket.
         */
        if ((inp->inp_vflag & INP_IPV4) &&
            inp->inp_laddr.s_addr == INADDR_ANY &&
            INP_CHECK_SOCKAF(inp->inp_socket, AF_INET6)) {
                return (0);
        }
#endif

        idx = INP_PCBPORTHASH(inp->inp_lport, pcbinfo->ipi_lbgrouphashmask);
        hdr = &pcbinfo->ipi_lbgrouphashbase[idx];
        CK_LIST_FOREACH(grp, hdr, il_list) {
                if (grp->il_cred->cr_prison == inp->inp_cred->cr_prison &&
                    grp->il_vflag == inp->inp_vflag &&
                    grp->il_lport == inp->inp_lport &&
                    grp->il_numa_domain == numa_domain &&
                    grp->il_fibnum == fib &&
                    memcmp(&grp->il_dependladdr,
                    &inp->inp_inc.inc_ie.ie_dependladdr,
                    sizeof(grp->il_dependladdr)) == 0) {
                        break;
                }
        }
        if (grp == NULL) {
                /* Create new load balance group. */
                grp = in_pcblbgroup_alloc(inp->inp_cred, inp->inp_vflag,
                    inp->inp_lport, &inp->inp_inc.inc_ie.ie_dependladdr,
                    INPCBLBGROUP_SIZMIN, numa_domain, fib);
                if (grp == NULL)
                        return (ENOMEM);
                in_pcblbgroup_insert(grp, inp);
                CK_LIST_INSERT_HEAD(hdr, grp, il_list);
        } else if (grp->il_inpcnt + grp->il_pendcnt == grp->il_inpsiz) {
                if (grp->il_inpsiz >= INPCBLBGROUP_SIZMAX) {
                        if (ratecheck(&lastprint, &interval))
                                printf("lb group port %d, limit reached\n",
                                    ntohs(grp->il_lport));
                        return (0);
                }

                /* Expand this local group. */
                grp = in_pcblbgroup_resize(hdr, grp, grp->il_inpsiz * 2);
                if (grp == NULL)
                        return (ENOMEM);
                in_pcblbgroup_insert(grp, inp);
        } else {
                in_pcblbgroup_insert(grp, inp);
        }
        return (0);
}

/*
 * Remove PCB from load balance group.
 */
static void
in_pcbremlbgrouphash(struct inpcb *inp)
{
        struct inpcbinfo *pcbinfo;
        struct inpcblbgrouphead *hdr;
        struct inpcblbgroup *grp;
        struct inpcb *inp1;
        int i;

        pcbinfo = inp->inp_pcbinfo;

        INP_WLOCK_ASSERT(inp);
        MPASS(inp->inp_flags & INP_INLBGROUP);
        INP_HASH_WLOCK_ASSERT(pcbinfo);

        hdr = &pcbinfo->ipi_lbgrouphashbase[
            INP_PCBPORTHASH(inp->inp_lport, pcbinfo->ipi_lbgrouphashmask)];
        CK_LIST_FOREACH(grp, hdr, il_list) {
                for (i = 0; i < grp->il_inpcnt; ++i) {
                        if (grp->il_inp[i] != inp)
                                continue;

                        if (grp->il_inpcnt == 1 &&
                            LIST_EMPTY(&grp->il_pending)) {
                                /* We are the last, free this local group. */
                                in_pcblbgroup_free(grp);
                        } else {
                                grp->il_inp[i] =
                                    grp->il_inp[grp->il_inpcnt - 1];

                                /*
                                 * Synchronize with in_pcblookup_lbgroup().
                                 */
                                atomic_store_rel_int(&grp->il_inpcnt,
                                    grp->il_inpcnt - 1);
                        }
                        inp->inp_flags &= ~INP_INLBGROUP;
                        return;
                }
                LIST_FOREACH(inp1, &grp->il_pending, inp_lbgroup_list) {
                        if (inp == inp1) {
                                LIST_REMOVE(inp, inp_lbgroup_list);
                                grp->il_pendcnt--;
                                inp->inp_flags &= ~INP_INLBGROUP;
                                return;
                        }
                }
        }
        __assert_unreachable();
}

int
in_pcblbgroup_numa(struct inpcb *inp, int arg)
{
        struct inpcbinfo *pcbinfo;
        int error;
        uint8_t numa_domain;

        switch (arg) {
        case TCP_REUSPORT_LB_NUMA_NODOM:
                numa_domain = M_NODOM;
                break;
        case TCP_REUSPORT_LB_NUMA_CURDOM:
                numa_domain = PCPU_GET(domain);
                break;
        default:
                if (arg < 0 || arg >= vm_ndomains)
                        return (EINVAL);
                numa_domain = arg;
        }

        pcbinfo = inp->inp_pcbinfo;
        INP_WLOCK_ASSERT(inp);
        INP_HASH_WLOCK(pcbinfo);
        if (in_pcblbgroup_find(inp) != NULL) {
                /* Remove it from the old group. */
                in_pcbremlbgrouphash(inp);
                /* Add it to the new group based on numa domain. */
                in_pcbinslbgrouphash(inp, numa_domain);
                error = 0;
        } else {
                error = ENOENT;
        }
        INP_HASH_WUNLOCK(pcbinfo);
        return (error);
}

/* Make sure it is safe to use hashinit(9) on CK_LIST. */
CTASSERT(sizeof(struct inpcbhead) == sizeof(LIST_HEAD(, inpcb)));

/*
 * Initialize an inpcbinfo - a per-VNET instance of connections db.
 */
void
in_pcbinfo_init(struct inpcbinfo *pcbinfo, struct inpcbstorage *pcbstor,
    u_int hash_nelements, u_int porthash_nelements)
{

        mtx_init(&pcbinfo->ipi_lock, pcbstor->ips_infolock_name, NULL, MTX_DEF);
        mtx_init(&pcbinfo->ipi_hash_lock, pcbstor->ips_hashlock_name,
            NULL, MTX_DEF);
#ifdef VIMAGE
        pcbinfo->ipi_vnet = curvnet;
#endif
        CK_LIST_INIT(&pcbinfo->ipi_listhead);
        pcbinfo->ipi_count = 0;
        pcbinfo->ipi_hash_exact = hashinit(hash_nelements, M_PCB,
            &pcbinfo->ipi_hashmask);
        pcbinfo->ipi_hash_wild = hashinit(hash_nelements, M_PCB,
            &pcbinfo->ipi_hashmask);
        porthash_nelements = imin(porthash_nelements, IPPORT_MAX + 1);
        pcbinfo->ipi_porthashbase = hashinit(porthash_nelements, M_PCB,
            &pcbinfo->ipi_porthashmask);
        pcbinfo->ipi_lbgrouphashbase = hashinit(porthash_nelements, M_PCB,
            &pcbinfo->ipi_lbgrouphashmask);
        pcbinfo->ipi_zone = pcbstor->ips_zone;
        pcbinfo->ipi_smr = uma_zone_get_smr(pcbinfo->ipi_zone);
}

/*
 * Destroy an inpcbinfo.
 */
void
in_pcbinfo_destroy(struct inpcbinfo *pcbinfo)
{

        KASSERT(pcbinfo->ipi_count == 0,
            ("%s: ipi_count = %u", __func__, pcbinfo->ipi_count));

        hashdestroy(pcbinfo->ipi_hash_exact, M_PCB, pcbinfo->ipi_hashmask);
        hashdestroy(pcbinfo->ipi_hash_wild, M_PCB, pcbinfo->ipi_hashmask);
        hashdestroy(pcbinfo->ipi_porthashbase, M_PCB,
            pcbinfo->ipi_porthashmask);
        hashdestroy(pcbinfo->ipi_lbgrouphashbase, M_PCB,
            pcbinfo->ipi_lbgrouphashmask);
        mtx_destroy(&pcbinfo->ipi_hash_lock);
        mtx_destroy(&pcbinfo->ipi_lock);
}

/*
 * Initialize a pcbstorage - per protocol zones to allocate inpcbs.
 */
static void inpcb_fini(void *, int);
void
in_pcbstorage_init(void *arg)
{
        struct inpcbstorage *pcbstor = arg;

        pcbstor->ips_zone = uma_zcreate(pcbstor->ips_zone_name,
            pcbstor->ips_size, NULL, NULL, pcbstor->ips_pcbinit,
            inpcb_fini, UMA_ALIGN_CACHE, UMA_ZONE_SMR);
}

/*
 * Destroy a pcbstorage - used by unloadable protocols.
 */
void
in_pcbstorage_destroy(void *arg)
{
        struct inpcbstorage *pcbstor = arg;

        uma_zdestroy(pcbstor->ips_zone);
}

/*
 * Allocate a PCB and associate it with the socket.
 * On success return with the PCB locked.
 */
int
in_pcballoc(struct socket *so, struct inpcbinfo *pcbinfo)
{
        struct inpcb *inp;
#if defined(IPSEC) || defined(IPSEC_SUPPORT) || defined(MAC)
        int error;
#endif

        inp = uma_zalloc_smr(pcbinfo->ipi_zone, M_NOWAIT);
        if (inp == NULL)
                return (ENOBUFS);
        bzero(&inp->inp_start_zero, inp_zero_size);
#ifdef NUMA
        inp->inp_numa_domain = M_NODOM;
#endif
        inp->inp_pcbinfo = pcbinfo;
        inp->inp_socket = so;
        inp->inp_cred = crhold(so->so_cred);
        inp->inp_inc.inc_fibnum = so->so_fibnum;
#ifdef MAC
        error = mac_inpcb_init(inp, M_NOWAIT);
        if (error != 0)
                goto out;
        mac_inpcb_create(so, inp);
#endif
#if defined(IPSEC) || defined(IPSEC_SUPPORT)
        error = ipsec_init_pcbpolicy(inp);
        if (error != 0) {
#ifdef MAC
                mac_inpcb_destroy(inp);
#endif
                goto out;
        }
#endif /*IPSEC*/
#ifdef INET6
        if (INP_SOCKAF(so) == AF_INET6) {
                inp->inp_vflag |= INP_IPV6PROTO | INP_IPV6;
                if (V_ip6_v6only)
                        inp->inp_flags |= IN6P_IPV6_V6ONLY;
#ifdef INET
                else
                        inp->inp_vflag |= INP_IPV4;
#endif
                if (V_ip6_auto_flowlabel)
                        inp->inp_flags |= IN6P_AUTOFLOWLABEL;
                inp->in6p_hops = -1;    /* use kernel default */
        }
#endif
#if defined(INET) && defined(INET6)
        else
#endif
#ifdef INET
                inp->inp_vflag |= INP_IPV4;
#endif
        inp->inp_smr = SMR_SEQ_INVALID;

        /*
         * Routes in inpcb's can cache L2 as well; they are guaranteed
         * to be cleaned up.
         */
        inp->inp_route.ro_flags = RT_LLE_CACHE;
        refcount_init(&inp->inp_refcount, 1);   /* Reference from socket. */
        INP_WLOCK(inp);
        INP_INFO_WLOCK(pcbinfo);
        pcbinfo->ipi_count++;
        inp->inp_gencnt = ++pcbinfo->ipi_gencnt;
        CK_LIST_INSERT_HEAD(&pcbinfo->ipi_listhead, inp, inp_list);
        INP_INFO_WUNLOCK(pcbinfo);
        so->so_pcb = inp;

        return (0);

#if defined(IPSEC) || defined(IPSEC_SUPPORT) || defined(MAC)
out:
        crfree(inp->inp_cred);
#ifdef INVARIANTS
        inp->inp_cred = NULL;
#endif
        uma_zfree_smr(pcbinfo->ipi_zone, inp);
        return (error);
#endif
}

#ifdef INET
int
in_pcbbind(struct inpcb *inp, struct sockaddr_in *sin, int flags,
    struct ucred *cred)
{
        int error;
        bool anonport;

        KASSERT(sin == NULL || sin->sin_family == AF_INET,
            ("%s: invalid address family for %p", __func__, sin));
        KASSERT(sin == NULL || sin->sin_len == sizeof(struct sockaddr_in),
            ("%s: invalid address length for %p", __func__, sin));
        INP_WLOCK_ASSERT(inp);
        INP_HASH_WLOCK_ASSERT(inp->inp_pcbinfo);

        if (inp->inp_lport != 0 || inp->inp_laddr.s_addr != INADDR_ANY)
                return (EINVAL);
        anonport = sin == NULL || sin->sin_port == 0;
        error = in_pcbbind_setup(inp, sin, &inp->inp_laddr.s_addr,
            &inp->inp_lport, flags, cred);
        if (error)
                return (error);
        if (__predict_false((error = in_pcbinshash(inp)) != 0)) {
                MPASS(inp->inp_socket->so_options & SO_REUSEPORT_LB);
                inp->inp_laddr.s_addr = INADDR_ANY;
                inp->inp_lport = 0;
                inp->inp_flags &= ~INP_BOUNDFIB;
                return (error);
        }
        if (anonport)
                inp->inp_flags |= INP_ANONPORT;
        return (0);
}
#endif

#if defined(INET) || defined(INET6)
/*
 * Assign a local port like in_pcb_lport(), but also used with connect()
 * and a foreign address and port.  If fsa is non-NULL, choose a local port
 * that is unused with those, otherwise one that is completely unused.
 * lsa can be NULL for IPv6.
 */
int
in_pcb_lport_dest(const struct inpcb *inp, struct sockaddr *lsa,
    u_short *lportp, struct sockaddr *fsa, u_short fport, struct ucred *cred,
    int lookupflags)
{
        struct inpcbinfo *pcbinfo;
        struct inpcb *tmpinp;
        unsigned short *lastport;
        int count, error;
        u_short aux, first, last, lport;
#ifdef INET
        struct in_addr laddr, faddr;
#endif
#ifdef INET6
        struct in6_addr *laddr6, *faddr6;
#endif

        pcbinfo = inp->inp_pcbinfo;

        /*
         * Because no actual state changes occur here, a global write lock on
         * the pcbinfo isn't required.
         */
        INP_LOCK_ASSERT(inp);
        INP_HASH_LOCK_ASSERT(pcbinfo);

        if (inp->inp_flags & INP_HIGHPORT) {
                first = V_ipport_hifirstauto;   /* sysctl */
                last  = V_ipport_hilastauto;
                lastport = &pcbinfo->ipi_lasthi;
        } else if (inp->inp_flags & INP_LOWPORT) {
                error = priv_check_cred(cred, PRIV_NETINET_RESERVEDPORT);
                if (error)
                        return (error);
                first = V_ipport_lowfirstauto;  /* 1023 */
                last  = V_ipport_lowlastauto;   /* 600 */
                lastport = &pcbinfo->ipi_lastlow;
        } else {
                first = V_ipport_firstauto;     /* sysctl */
                last  = V_ipport_lastauto;
                lastport = &pcbinfo->ipi_lastport;
        }

        /*
         * Instead of having two loops further down counting up or down
         * make sure that first is always <= last and go with only one
         * code path implementing all logic.
         */
        if (first > last) {
                aux = first;
                first = last;
                last = aux;
        }

#ifdef INET
        laddr.s_addr = INADDR_ANY;      /* used by INET6+INET below too */
        if ((inp->inp_vflag & (INP_IPV4|INP_IPV6)) == INP_IPV4) {
                if (lsa != NULL)
                        laddr = ((struct sockaddr_in *)lsa)->sin_addr;
                if (fsa != NULL)
                        faddr = ((struct sockaddr_in *)fsa)->sin_addr;
        }
#endif
#ifdef INET6
        laddr6 = NULL;
        if ((inp->inp_vflag & INP_IPV6) != 0) {
                if (lsa != NULL)
                        laddr6 = &((struct sockaddr_in6 *)lsa)->sin6_addr;
                if (fsa != NULL)
                        faddr6 = &((struct sockaddr_in6 *)fsa)->sin6_addr;
        }
#endif

        tmpinp = NULL;

        if (V_ipport_randomized)
                *lastport = first + (arc4random() % (last - first));

        count = last - first;

        do {
                if (count-- < 0)        /* completely used? */
                        return (EADDRNOTAVAIL);
                ++*lastport;
                if (*lastport < first || *lastport > last)
                        *lastport = first;
                lport = htons(*lastport);

                if (fsa != NULL) {
#ifdef INET
                        if (lsa->sa_family == AF_INET) {
                                tmpinp = in_pcblookup_hash_locked(pcbinfo,
                                    faddr, fport, laddr, lport, lookupflags,
                                    M_NODOM, RT_ALL_FIBS);
                        }
#endif
#ifdef INET6
                        if (lsa->sa_family == AF_INET6) {
                                tmpinp = in6_pcblookup_hash_locked(pcbinfo,
                                    faddr6, fport, laddr6, lport, lookupflags,
                                    M_NODOM, RT_ALL_FIBS);
                        }
#endif
                } else {
#ifdef INET6
                        if ((inp->inp_vflag & INP_IPV6) != 0) {
                                tmpinp = in6_pcblookup_local(pcbinfo,
                                    &inp->in6p_laddr, lport, RT_ALL_FIBS,
                                    lookupflags, cred);
#ifdef INET
                                if (tmpinp == NULL &&
                                    (inp->inp_vflag & INP_IPV4))
                                        tmpinp = in_pcblookup_local(pcbinfo,
                                            laddr, lport, RT_ALL_FIBS,
                                            lookupflags, cred);
#endif
                        }
#endif
#if defined(INET) && defined(INET6)
                        else
#endif
#ifdef INET
                                tmpinp = in_pcblookup_local(pcbinfo, laddr,
                                    lport, RT_ALL_FIBS, lookupflags, cred);
#endif
                }
        } while (tmpinp != NULL);

        *lportp = lport;

        return (0);
}

/*
 * Select a local port (number) to use.
 */
int
in_pcb_lport(struct inpcb *inp, struct in_addr *laddrp, u_short *lportp,
    struct ucred *cred, int lookupflags)
{
        struct sockaddr_in laddr;

        if (laddrp) {
                bzero(&laddr, sizeof(laddr));
                laddr.sin_family = AF_INET;
                laddr.sin_addr = *laddrp;
        }
        return (in_pcb_lport_dest(inp, laddrp ? (struct sockaddr *) &laddr :
            NULL, lportp, NULL, 0, cred, lookupflags));
}
#endif /* INET || INET6 */

#ifdef INET
/*
 * Determine whether the inpcb can be bound to the specified address/port tuple.
 */
static int
in_pcbbind_avail(struct inpcb *inp, const struct in_addr laddr,
    const u_short lport, const int fib, int sooptions, int lookupflags,
    struct ucred *cred)
{
        int reuseport, reuseport_lb;

        INP_LOCK_ASSERT(inp);
        INP_HASH_LOCK_ASSERT(inp->inp_pcbinfo);

        reuseport = (sooptions & SO_REUSEPORT);
        reuseport_lb = (sooptions & SO_REUSEPORT_LB);

        if (IN_MULTICAST(ntohl(laddr.s_addr))) {
                /*
                 * Treat SO_REUSEADDR as SO_REUSEPORT for multicast;
                 * allow complete duplication of binding if
                 * SO_REUSEPORT is set, or if SO_REUSEADDR is set
                 * and a multicast address is bound on both
                 * new and duplicated sockets.
                 */
                if ((sooptions & (SO_REUSEADDR | SO_REUSEPORT)) != 0)
                        reuseport = SO_REUSEADDR | SO_REUSEPORT;
                /*
                 * XXX: How to deal with SO_REUSEPORT_LB here?
                 * Treat same as SO_REUSEPORT for now.
                 */
                if ((sooptions & (SO_REUSEADDR | SO_REUSEPORT_LB)) != 0)
                        reuseport_lb = SO_REUSEADDR | SO_REUSEPORT_LB;
        } else if (!in_nullhost(laddr)) {
                struct sockaddr_in sin;

                memset(&sin, 0, sizeof(sin));
                sin.sin_family = AF_INET;
                sin.sin_len = sizeof(sin);
                sin.sin_addr = laddr;

                /*
                 * Is the address a local IP address?
                 * If INP_BINDANY is set, then the socket may be bound
                 * to any endpoint address, local or not.
                 */
                if ((inp->inp_flags & INP_BINDANY) == 0 &&
                    ifa_ifwithaddr_check((const struct sockaddr *)&sin) == 0)
                        return (EADDRNOTAVAIL);
        }

        if (lport != 0) {
                struct inpcb *t;

                if (ntohs(lport) <= V_ipport_reservedhigh &&
                    ntohs(lport) >= V_ipport_reservedlow &&
                    priv_check_cred(cred, PRIV_NETINET_RESERVEDPORT))
                        return (EACCES);

                if (!IN_MULTICAST(ntohl(laddr.s_addr)) &&
                    priv_check_cred(inp->inp_cred, PRIV_NETINET_REUSEPORT) != 0) {
                        /*
                         * If a socket owned by a different user is already
                         * bound to this port, fail.  In particular, SO_REUSE*
                         * can only be used to share a port among sockets owned
                         * by the same user.
                         *
                         * However, we can share a port with a connected socket
                         * which has a unique 4-tuple.
                         */
                        t = in_pcblookup_local(inp->inp_pcbinfo, laddr, lport,
                            RT_ALL_FIBS, INPLOOKUP_WILDCARD, cred);
                        if (t != NULL &&
                            (inp->inp_socket->so_type != SOCK_STREAM ||
                             in_nullhost(t->inp_faddr)) &&
                            (inp->inp_cred->cr_uid != t->inp_cred->cr_uid))
                                return (EADDRINUSE);
                }
                t = in_pcblookup_local(inp->inp_pcbinfo, laddr, lport, fib,
                    lookupflags, cred);
                if (t != NULL && ((reuseport | reuseport_lb) &
                    t->inp_socket->so_options) == 0) {
#ifdef INET6
                        if (!in_nullhost(laddr) ||
                            !in_nullhost(t->inp_laddr) ||
                            (inp->inp_vflag & INP_IPV6PROTO) == 0 ||
                            (t->inp_vflag & INP_IPV6PROTO) == 0)
#endif
                                return (EADDRINUSE);
                }
        }
        return (0);
}

/*
 * Set up a bind operation on a PCB, performing port allocation
 * as required, but do not actually modify the PCB. Callers can
 * either complete the bind by setting inp_laddr/inp_lport and
 * calling in_pcbinshash(), or they can just use the resulting
 * port and address to authorise the sending of a once-off packet.
 *
 * On error, the values of *laddrp and *lportp are not changed.
 */
int
in_pcbbind_setup(struct inpcb *inp, struct sockaddr_in *sin, in_addr_t *laddrp,
    u_short *lportp, int flags, struct ucred *cred)
{
        struct socket *so = inp->inp_socket;
        struct in_addr laddr;
        u_short lport = 0;
        int error, fib, lookupflags, sooptions;

        /*
         * No state changes, so read locks are sufficient here.
         */
        INP_LOCK_ASSERT(inp);
        INP_HASH_LOCK_ASSERT(inp->inp_pcbinfo);

        laddr.s_addr = *laddrp;
        if (sin != NULL && laddr.s_addr != INADDR_ANY)
                return (EINVAL);

        lookupflags = 0;
        sooptions = atomic_load_int(&so->so_options);
        if ((sooptions & (SO_REUSEADDR | SO_REUSEPORT | SO_REUSEPORT_LB)) == 0)
                lookupflags = INPLOOKUP_WILDCARD;
        if (sin == NULL) {
                if ((error = prison_local_ip4(cred, &laddr)) != 0)
                        return (error);
        } else {
                KASSERT(sin->sin_family == AF_INET,
                    ("%s: invalid family for address %p", __func__, sin));
                KASSERT(sin->sin_len == sizeof(*sin),
                    ("%s: invalid length for address %p", __func__, sin));

                error = prison_local_ip4(cred, &sin->sin_addr);
                if (error)
                        return (error);
                if (sin->sin_port != *lportp) {
                        /* Don't allow the port to change. */
                        if (*lportp != 0)
                                return (EINVAL);
                        lport = sin->sin_port;
                }
                laddr = sin->sin_addr;

                fib = (flags & INPBIND_FIB) != 0 ? inp->inp_inc.inc_fibnum :
                    RT_ALL_FIBS;

                /* See if this address/port combo is available. */
                error = in_pcbbind_avail(inp, laddr, lport, fib, sooptions,
                    lookupflags, cred);
                if (error != 0)
                        return (error);
        }
        if (*lportp != 0)
                lport = *lportp;
        if (lport == 0) {
                error = in_pcb_lport(inp, &laddr, &lport, cred, lookupflags);
                if (error != 0)
                        return (error);
        }
        *laddrp = laddr.s_addr;
        *lportp = lport;
        if ((flags & INPBIND_FIB) != 0)
                inp->inp_flags |= INP_BOUNDFIB;
        return (0);
}

/*
 * Connect from a socket to a specified address.
 * Both address and port must be specified in argument sin.
 * If don't have a local address for this socket yet,
 * then pick one.
 */
int
in_pcbconnect(struct inpcb *inp, struct sockaddr_in *sin, struct ucred *cred)
{
        struct in_addr laddr, faddr;
        u_short lport;
        int error;
        bool anonport;

        INP_WLOCK_ASSERT(inp);
        INP_HASH_WLOCK_ASSERT(inp->inp_pcbinfo);
        KASSERT(in_nullhost(inp->inp_faddr),
            ("%s: inp is already connected", __func__));
        KASSERT(sin->sin_family == AF_INET,
            ("%s: invalid address family for %p", __func__, sin));
        KASSERT(sin->sin_len == sizeof(*sin),
            ("%s: invalid address length for %p", __func__, sin));

        if (sin->sin_port == 0)
                return (EADDRNOTAVAIL);

        anonport = (inp->inp_lport == 0);

        if (__predict_false(in_broadcast(sin->sin_addr))) {
                if (!V_connect_inaddr_wild || CK_STAILQ_EMPTY(&V_in_ifaddrhead))
                        return (ENETUNREACH);
                /*
                 * If the destination address is INADDR_ANY, use the primary
                 * local address.  If the supplied address is INADDR_BROADCAST,
                 * and the primary interface supports broadcast, choose the
                 * broadcast address for that interface.
                 */
                if (in_nullhost(sin->sin_addr)) {
                        faddr =
                            IA_SIN(CK_STAILQ_FIRST(&V_in_ifaddrhead))->sin_addr;
                        if ((error = prison_get_ip4(cred, &faddr)) != 0)
                                return (error);
                } else if (sin->sin_addr.s_addr == INADDR_BROADCAST &&
                    CK_STAILQ_FIRST(&V_in_ifaddrhead)->ia_ifp->if_flags
                    & IFF_BROADCAST) {
                        faddr = satosin(&CK_STAILQ_FIRST(
                            &V_in_ifaddrhead)->ia_broadaddr)->sin_addr;
                } else
                        faddr = sin->sin_addr;
        } else
                faddr = sin->sin_addr;

        if (in_nullhost(inp->inp_laddr)) {
                error = in_pcbladdr(inp, &faddr, &laddr, cred);
                if (error)
                        return (error);
        } else
                laddr = inp->inp_laddr;

        if (anonport) {
                struct sockaddr_in lsin = {
                        .sin_family = AF_INET,
                        .sin_addr = laddr,
                };
                struct sockaddr_in fsin = {
                        .sin_family = AF_INET,
                        .sin_addr = faddr,
                };

                error = in_pcb_lport_dest(inp, (struct sockaddr *)&lsin,
                    &lport, (struct sockaddr *)&fsin, sin->sin_port, cred,
                    INPLOOKUP_WILDCARD);
                if (error)
                        return (error);
        } else if (in_pcblookup_hash_locked(inp->inp_pcbinfo, faddr,
            sin->sin_port, laddr, inp->inp_lport, 0, M_NODOM, RT_ALL_FIBS) !=
            NULL)
                return (EADDRINUSE);
        else
                lport = inp->inp_lport;

        MPASS(!in_nullhost(inp->inp_laddr) || inp->inp_lport != 0 ||
            !(inp->inp_flags & INP_INHASHLIST));

        inp->inp_faddr = faddr;
        inp->inp_fport = sin->sin_port;
        inp->inp_laddr = laddr;
        inp->inp_lport = lport;

        if ((inp->inp_flags & INP_INHASHLIST) == 0) {
                error = in_pcbinshash(inp);
                MPASS(error == 0);
        } else
                in_pcbrehash(inp);

        if (V_fib_hash_outbound) {
                uint32_t hash_val, hash_type;

                hash_val = fib4_calc_software_hash(inp->inp_laddr,
                    inp->inp_faddr, 0, sin->sin_port,
                    inp->inp_socket->so_proto->pr_protocol, &hash_type);

                inp->inp_flowid = hash_val;
                inp->inp_flowtype = hash_type;
        }
        if (anonport)
                inp->inp_flags |= INP_ANONPORT;
        return (0);
}

/*
 * Do proper source address selection on an unbound socket in case
 * of connect. Take jails into account as well.
 */
int
in_pcbladdr(const struct inpcb *inp, struct in_addr *faddr,
    struct in_addr *laddr, struct ucred *cred)
{
        struct ifaddr *ifa;
        struct sockaddr *sa;
        struct sockaddr_in *sin, dst;
        struct nhop_object *nh;
        int error;

        NET_EPOCH_ASSERT();
        KASSERT(laddr != NULL, ("%s: laddr NULL", __func__));

        /*
         * Bypass source address selection and use the primary jail IP
         * if requested.
         */
        if (!prison_saddrsel_ip4(cred, laddr))
                return (0);

        /*
         * If the destination address is multicast and an outgoing
         * interface has been set as a multicast option, prefer the
         * address of that interface as our source address.
         */
        if (IN_MULTICAST(ntohl(faddr->s_addr)) && inp->inp_moptions != NULL &&
            inp->inp_moptions->imo_multicast_ifp != NULL) {
                struct ifnet *ifp = inp->inp_moptions->imo_multicast_ifp;
                struct in_ifaddr *ia;

                CK_STAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
                        if (ia->ia_ifp == ifp &&
                            prison_check_ip4(cred, &ia->ia_addr.sin_addr) == 0)
                                break;
                }
                if (ia == NULL)
                        return (EADDRNOTAVAIL);
                *laddr = ia->ia_addr.sin_addr;
                return (0);
        }

        error = 0;

        nh = NULL;
        bzero(&dst, sizeof(dst));
        sin = &dst;
        sin->sin_family = AF_INET;
        sin->sin_len = sizeof(struct sockaddr_in);
        sin->sin_addr.s_addr = faddr->s_addr;

        /*
         * If route is known our src addr is taken from the i/f,
         * else punt.
         *
         * Find out route to destination.
         */
        if ((inp->inp_socket->so_options & SO_DONTROUTE) == 0)
                nh = fib4_lookup(inp->inp_inc.inc_fibnum, *faddr,
                    0, NHR_NONE, 0);

        /*
         * If we found a route, use the address corresponding to
         * the outgoing interface.
         *
         * Otherwise assume faddr is reachable on a directly connected
         * network and try to find a corresponding interface to take
         * the source address from.
         */
        if (nh == NULL || nh->nh_ifp == NULL) {
                struct in_ifaddr *ia;
                struct ifnet *ifp;

                ia = ifatoia(ifa_ifwithdstaddr((struct sockaddr *)sin,
                                        inp->inp_socket->so_fibnum));
                if (ia == NULL) {
                        ia = ifatoia(ifa_ifwithnet((struct sockaddr *)sin, 0,
                                                inp->inp_socket->so_fibnum));
                }
                if (ia == NULL) {
                        error = ENETUNREACH;
                        goto done;
                }

                if (!prison_flag(cred, PR_IP4)) {
                        laddr->s_addr = ia->ia_addr.sin_addr.s_addr;
                        goto done;
                }

                ifp = ia->ia_ifp;
                ia = NULL;
                CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
                        sa = ifa->ifa_addr;
                        if (sa->sa_family != AF_INET)
                                continue;
                        sin = (struct sockaddr_in *)sa;
                        if (prison_check_ip4(cred, &sin->sin_addr) == 0) {
                                ia = (struct in_ifaddr *)ifa;
                                break;
                        }
                }
                if (ia != NULL) {
                        laddr->s_addr = ia->ia_addr.sin_addr.s_addr;
                        goto done;
                }

                /* 3. As a last resort return the 'default' jail address. */
                error = prison_get_ip4(cred, laddr);
                goto done;
        }

        /*
         * If the outgoing interface on the route found is not
         * a loopback interface, use the address from that interface.
         * In case of jails do those three steps:
         * 1. check if the interface address belongs to the jail. If so use it.
         * 2. check if we have any address on the outgoing interface
         *    belonging to this jail. If so use it.
         * 3. as a last resort return the 'default' jail address.
         */
        if ((nh->nh_ifp->if_flags & IFF_LOOPBACK) == 0) {
                struct in_ifaddr *ia;
                struct ifnet *ifp;

                /* If not jailed, use the default returned. */
                if (!prison_flag(cred, PR_IP4)) {
                        ia = (struct in_ifaddr *)nh->nh_ifa;
                        laddr->s_addr = ia->ia_addr.sin_addr.s_addr;
                        goto done;
                }

                /* Jailed. */
                /* 1. Check if the iface address belongs to the jail. */
                sin = (struct sockaddr_in *)nh->nh_ifa->ifa_addr;
                if (prison_check_ip4(cred, &sin->sin_addr) == 0) {
                        ia = (struct in_ifaddr *)nh->nh_ifa;
                        laddr->s_addr = ia->ia_addr.sin_addr.s_addr;
                        goto done;
                }

                /*
                 * 2. Check if we have any address on the outgoing interface
                 *    belonging to this jail.
                 */
                ia = NULL;
                ifp = nh->nh_ifp;
                CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
                        sa = ifa->ifa_addr;
                        if (sa->sa_family != AF_INET)
                                continue;
                        sin = (struct sockaddr_in *)sa;
                        if (prison_check_ip4(cred, &sin->sin_addr) == 0) {
                                ia = (struct in_ifaddr *)ifa;
                                break;
                        }
                }
                if (ia != NULL) {
                        laddr->s_addr = ia->ia_addr.sin_addr.s_addr;
                        goto done;
                }

                /* 3. As a last resort return the 'default' jail address. */
                error = prison_get_ip4(cred, laddr);
                goto done;
        }

        /*
         * The outgoing interface is marked with 'loopback net', so a route
         * to ourselves is here.
         * Try to find the interface of the destination address and then
         * take the address from there. That interface is not necessarily
         * a loopback interface.
         * In case of jails, check that it is an address of the jail
         * and if we cannot find, fall back to the 'default' jail address.
         */
        if ((nh->nh_ifp->if_flags & IFF_LOOPBACK) != 0) {
                struct in_ifaddr *ia;

                ia = ifatoia(ifa_ifwithdstaddr(sintosa(&dst),
                                        inp->inp_socket->so_fibnum));
                if (ia == NULL)
                        ia = ifatoia(ifa_ifwithnet(sintosa(&dst), 0,
                                                inp->inp_socket->so_fibnum));
                if (ia == NULL)
                        ia = ifatoia(ifa_ifwithaddr(sintosa(&dst)));

                if (!prison_flag(cred, PR_IP4)) {
                        if (ia == NULL) {
                                error = ENETUNREACH;
                                goto done;
                        }
                        laddr->s_addr = ia->ia_addr.sin_addr.s_addr;
                        goto done;
                }

                /* Jailed. */
                if (ia != NULL) {
                        struct ifnet *ifp;

                        ifp = ia->ia_ifp;
                        ia = NULL;
                        CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
                                sa = ifa->ifa_addr;
                                if (sa->sa_family != AF_INET)
                                        continue;
                                sin = (struct sockaddr_in *)sa;
                                if (prison_check_ip4(cred,
                                    &sin->sin_addr) == 0) {
                                        ia = (struct in_ifaddr *)ifa;
                                        break;
                                }
                        }
                        if (ia != NULL) {
                                laddr->s_addr = ia->ia_addr.sin_addr.s_addr;
                                goto done;
                        }
                }

                /* 3. As a last resort return the 'default' jail address. */
                error = prison_get_ip4(cred, laddr);
                goto done;
        }

done:
        if (error == 0 && laddr->s_addr == INADDR_ANY)
                return (EHOSTUNREACH);
        return (error);
}

void
in_pcbdisconnect(struct inpcb *inp)
{

        INP_WLOCK_ASSERT(inp);
        INP_HASH_WLOCK_ASSERT(inp->inp_pcbinfo);
        KASSERT(inp->inp_smr == SMR_SEQ_INVALID,
            ("%s: inp %p was already disconnected", __func__, inp));

        in_pcbremhash_locked(inp);

        /* See the comment in in_pcbinshash(). */
        inp->inp_smr = smr_advance(inp->inp_pcbinfo->ipi_smr);
        inp->inp_laddr.s_addr = INADDR_ANY;
        inp->inp_faddr.s_addr = INADDR_ANY;
        inp->inp_fport = 0;
}
#endif /* INET */

void
in_pcblisten(struct inpcb *inp)
{
        struct inpcblbgroup *grp;

        INP_WLOCK_ASSERT(inp);

        if ((inp->inp_flags & INP_INLBGROUP) != 0) {
                struct inpcbinfo *pcbinfo;

                pcbinfo = inp->inp_pcbinfo;
                INP_HASH_WLOCK(pcbinfo);
                grp = in_pcblbgroup_find(inp);
                LIST_REMOVE(inp, inp_lbgroup_list);
                grp->il_pendcnt--;
                in_pcblbgroup_insert(grp, inp);
                INP_HASH_WUNLOCK(pcbinfo);
        }
}

/*
 * inpcb hash lookups are protected by SMR section.
 *
 * Once desired pcb has been found, switching from SMR section to a pcb
 * lock is performed with inp_smr_lock(). We can not use INP_(W|R)LOCK
 * here because SMR is a critical section.
 * In 99%+ cases inp_smr_lock() would obtain the lock immediately.
 */
void
inp_lock(struct inpcb *inp, const inp_lookup_t lock)
{

        lock == INPLOOKUP_RLOCKPCB ?
            rw_rlock(&inp->inp_lock) : rw_wlock(&inp->inp_lock);
}

void
inp_unlock(struct inpcb *inp, const inp_lookup_t lock)
{

        lock == INPLOOKUP_RLOCKPCB ?
            rw_runlock(&inp->inp_lock) : rw_wunlock(&inp->inp_lock);
}

int
inp_trylock(struct inpcb *inp, const inp_lookup_t lock)
{

        return (lock == INPLOOKUP_RLOCKPCB ?
            rw_try_rlock(&inp->inp_lock) : rw_try_wlock(&inp->inp_lock));
}

static inline bool
_inp_smr_lock(struct inpcb *inp, const inp_lookup_t lock, const int ignflags)
{

        MPASS(lock == INPLOOKUP_RLOCKPCB || lock == INPLOOKUP_WLOCKPCB);
        SMR_ASSERT_ENTERED(inp->inp_pcbinfo->ipi_smr);

        if (__predict_true(inp_trylock(inp, lock))) {
                if (__predict_false(inp->inp_flags & ignflags)) {
                        smr_exit(inp->inp_pcbinfo->ipi_smr);
                        inp_unlock(inp, lock);
                        return (false);
                }
                smr_exit(inp->inp_pcbinfo->ipi_smr);
                return (true);
        }

        if (__predict_true(refcount_acquire_if_not_zero(&inp->inp_refcount))) {
                smr_exit(inp->inp_pcbinfo->ipi_smr);
                inp_lock(inp, lock);
                if (__predict_false(in_pcbrele(inp, lock)))
                        return (false);
                /*
                 * inp acquired through refcount & lock for sure didn't went
                 * through uma_zfree().  However, it may have already went
                 * through in_pcbfree() and has another reference, that
                 * prevented its release by our in_pcbrele().
                 */
                if (__predict_false(inp->inp_flags & ignflags)) {
                        inp_unlock(inp, lock);
                        return (false);
                }
                return (true);
        } else {
                smr_exit(inp->inp_pcbinfo->ipi_smr);
                return (false);
        }
}

bool
inp_smr_lock(struct inpcb *inp, const inp_lookup_t lock)
{

        /*
         * in_pcblookup() family of functions ignore not only freed entries,
         * that may be found due to lockless access to the hash, but dropped
         * entries, too.
         */
        return (_inp_smr_lock(inp, lock, INP_FREED | INP_DROPPED));
}

/*
 * inp_next() - inpcb hash/list traversal iterator
 *
 * Requires initialized struct inpcb_iterator for context.
 * The structure can be initialized with INP_ITERATOR() or INP_ALL_ITERATOR().
 *
 * - Iterator can have either write-lock or read-lock semantics, that can not
 *   be changed later.
 * - Iterator can iterate either over all pcbs list (INP_ALL_LIST), or through
 *   a single hash slot.  Note: only rip_input() does the latter.
 * - Iterator may have optional bool matching function.  The matching function
 *   will be executed for each inpcb in the SMR context, so it can not acquire
 *   locks and can safely access only immutable fields of inpcb.
 *
 * A fresh initialized iterator has NULL inpcb in its context and that
 * means that inp_next() call would return the very first inpcb on the list
 * locked with desired semantic.  In all following calls the context pointer
 * shall hold the current inpcb pointer.  The KPI user is not supposed to
 * unlock the current inpcb!  Upon end of traversal inp_next() will return NULL
 * and write NULL to its context.  After end of traversal an iterator can be
 * reused.
 *
 * List traversals have the following features/constraints:
 * - New entries won't be seen, as they are always added to the head of a list.
 * - Removed entries won't stop traversal as long as they are not added to
 *   a different list. This is violated by in_pcbrehash().
 */
#define II_LIST_FIRST(ipi, hash)                                        \
                (((hash) == INP_ALL_LIST) ?                             \
                    CK_LIST_FIRST(&(ipi)->ipi_listhead) :               \
                    CK_LIST_FIRST(&(ipi)->ipi_hash_exact[(hash)]))
#define II_LIST_NEXT(inp, hash)                                         \
                (((hash) == INP_ALL_LIST) ?                             \
                    CK_LIST_NEXT((inp), inp_list) :                     \
                    CK_LIST_NEXT((inp), inp_hash_exact))
#define II_LOCK_ASSERT(inp, lock)                                       \
                rw_assert(&(inp)->inp_lock,                             \
                    (lock) == INPLOOKUP_RLOCKPCB ?  RA_RLOCKED : RA_WLOCKED )
struct inpcb *
inp_next(struct inpcb_iterator *ii)
{
        const struct inpcbinfo *ipi = ii->ipi;
        inp_match_t *match = ii->match;
        void *ctx = ii->ctx;
        inp_lookup_t lock = ii->lock;
        int hash = ii->hash;
        struct inpcb *inp;

        if (ii->inp == NULL) {          /* First call. */
                smr_enter(ipi->ipi_smr);
                /* This is unrolled CK_LIST_FOREACH(). */
                for (inp = II_LIST_FIRST(ipi, hash);
                    inp != NULL;
                    inp = II_LIST_NEXT(inp, hash)) {
                        if (match != NULL && (match)(inp, ctx) == false)
                                continue;
                        if (__predict_true(_inp_smr_lock(inp, lock, INP_FREED)))
                                break;
                        else {
                                smr_enter(ipi->ipi_smr);
                                MPASS(inp != II_LIST_FIRST(ipi, hash));
                                inp = II_LIST_FIRST(ipi, hash);
                                if (inp == NULL)
                                        break;
                        }
                }

                if (inp == NULL)
                        smr_exit(ipi->ipi_smr);
                else
                        ii->inp = inp;

                return (inp);
        }

        /* Not a first call. */
        smr_enter(ipi->ipi_smr);
restart:
        inp = ii->inp;
        II_LOCK_ASSERT(inp, lock);
next:
        inp = II_LIST_NEXT(inp, hash);
        if (inp == NULL) {
                smr_exit(ipi->ipi_smr);
                goto found;
        }

        if (match != NULL && (match)(inp, ctx) == false)
                goto next;

        if (__predict_true(inp_trylock(inp, lock))) {
                if (__predict_false(inp->inp_flags & INP_FREED)) {
                        /*
                         * Entries are never inserted in middle of a list, thus
                         * as long as we are in SMR, we can continue traversal.
                         * Jump to 'next' should yield in the same result, but
                         * could produce unnecessary looping.  Could this
                         * looping be unbound?
                         */
                        inp_unlock(inp, lock);
                        goto next;
                } else {
                        smr_exit(ipi->ipi_smr);
                        goto found;
                }
        }

        /*
         * Can't obtain lock immediately, thus going hard.  Once we exit the
         * SMR section we can no longer jump to 'next', and our only stable
         * anchoring point is ii->inp, which we keep locked for this case, so
         * we jump to 'restart'.
         */
        if (__predict_true(refcount_acquire_if_not_zero(&inp->inp_refcount))) {
                smr_exit(ipi->ipi_smr);
                inp_lock(inp, lock);
                if (__predict_false(in_pcbrele(inp, lock))) {
                        smr_enter(ipi->ipi_smr);
                        goto restart;
                }
                /*
                 * See comment in inp_smr_lock().
                 */
                if (__predict_false(inp->inp_flags & INP_FREED)) {
                        inp_unlock(inp, lock);
                        smr_enter(ipi->ipi_smr);
                        goto restart;
                }
        } else
                goto next;

found:
        inp_unlock(ii->inp, lock);
        ii->inp = inp;

        return (ii->inp);
}

/*
 * in_pcbref() bumps the reference count on an inpcb in order to maintain
 * stability of an inpcb pointer despite the inpcb lock being released or
 * SMR section exited.
 *
 * To free a reference later in_pcbrele_(r|w)locked() must be performed.
 */
void
in_pcbref(struct inpcb *inp)
{
        u_int old __diagused;

        old = refcount_acquire(&inp->inp_refcount);
        KASSERT(old > 0, ("%s: refcount 0", __func__));
}

/*
 * Drop a refcount on an inpcb elevated using in_pcbref(), potentially
 * freeing the pcb, if the reference was very last.
 */
bool
in_pcbrele_rlocked(struct inpcb *inp)
{

        INP_RLOCK_ASSERT(inp);

        if (!refcount_release(&inp->inp_refcount))
                return (false);

        MPASS(inp->inp_flags & INP_FREED);
        MPASS(inp->inp_socket == NULL);
        crfree(inp->inp_cred);
#ifdef INVARIANTS
        inp->inp_cred = NULL;
#endif
        INP_RUNLOCK(inp);
        uma_zfree_smr(inp->inp_pcbinfo->ipi_zone, inp);
        return (true);
}

bool
in_pcbrele_wlocked(struct inpcb *inp)
{

        INP_WLOCK_ASSERT(inp);

        if (!refcount_release(&inp->inp_refcount))
                return (false);

        MPASS(inp->inp_flags & INP_FREED);
        MPASS(inp->inp_socket == NULL);
        crfree(inp->inp_cred);
#ifdef INVARIANTS
        inp->inp_cred = NULL;
#endif
        INP_WUNLOCK(inp);
        uma_zfree_smr(inp->inp_pcbinfo->ipi_zone, inp);
        return (true);
}

bool
in_pcbrele(struct inpcb *inp, const inp_lookup_t lock)
{

        return (lock == INPLOOKUP_RLOCKPCB ?
            in_pcbrele_rlocked(inp) : in_pcbrele_wlocked(inp));
}

/*
 * Dereference and rlock inp, for which the caller must own the
 * reference.  Returns true if inp no longer usable, false otherwise.
 */
bool
in_pcbrele_rlock(struct inpcb *inp)
{
        INP_RLOCK(inp);
        if (in_pcbrele_rlocked(inp))
                return (true);
        if ((inp->inp_flags & INP_FREED) != 0) {
                INP_RUNLOCK(inp);
                return (true);
        }
        return (false);
}

/*
 * Unconditionally schedule an inpcb to be freed by decrementing its
 * reference count, which should occur only after the inpcb has been detached
 * from its socket.  If another thread holds a temporary reference (acquired
 * using in_pcbref()) then the free is deferred until that reference is
 * released using in_pcbrele_(r|w)locked(), but the inpcb is still unlocked.
 *  Almost all work, including removal from global lists, is done in this
 * context, where the pcbinfo lock is held.
 */
void
in_pcbfree(struct inpcb *inp)
{
        struct inpcbinfo *pcbinfo = inp->inp_pcbinfo;
#ifdef INET
        struct ip_moptions *imo;
#endif
#ifdef INET6
        struct ip6_moptions *im6o;
#endif

        INP_WLOCK_ASSERT(inp);
        KASSERT(inp->inp_socket != NULL, ("%s: inp_socket == NULL", __func__));
        KASSERT((inp->inp_flags & INP_FREED) == 0,
            ("%s: called twice for pcb %p", __func__, inp));

        /*
         * in_pcblookup_local() and in6_pcblookup_local() may return an inpcb
         * from the hash without acquiring inpcb lock, they rely on the hash
         * lock, thus in_pcbremhash() should be the first action.
         */
        if (inp->inp_flags & INP_INHASHLIST)
                in_pcbremhash(inp);
        INP_INFO_WLOCK(pcbinfo);
        inp->inp_gencnt = ++pcbinfo->ipi_gencnt;
        pcbinfo->ipi_count--;
        CK_LIST_REMOVE(inp, inp_list);
        INP_INFO_WUNLOCK(pcbinfo);

#ifdef RATELIMIT
        if (inp->inp_snd_tag != NULL)
                in_pcbdetach_txrtlmt(inp);
#endif
        inp->inp_flags |= INP_FREED;
        inp->inp_socket->so_pcb = NULL;
        inp->inp_socket = NULL;

        RO_INVALIDATE_CACHE(&inp->inp_route);
#ifdef MAC
        mac_inpcb_destroy(inp);
#endif
#if defined(IPSEC) || defined(IPSEC_SUPPORT)
        if (inp->inp_sp != NULL)
                ipsec_delete_pcbpolicy(inp);
#endif
#ifdef INET
        if (inp->inp_options)
                (void)m_free(inp->inp_options);
        DEBUG_POISON_POINTER(inp->inp_options);
        imo = inp->inp_moptions;
        DEBUG_POISON_POINTER(inp->inp_moptions);
#endif
#ifdef INET6
        if (inp->inp_vflag & INP_IPV6PROTO) {
                ip6_freepcbopts(inp->in6p_outputopts);
                DEBUG_POISON_POINTER(inp->in6p_outputopts);
                im6o = inp->in6p_moptions;
                DEBUG_POISON_POINTER(inp->in6p_moptions);
        } else
                im6o = NULL;
#endif

        if (__predict_false(in_pcbrele_wlocked(inp) == false)) {
                INP_WUNLOCK(inp);
        }
#ifdef INET6
        ip6_freemoptions(im6o);
#endif
#ifdef INET
        inp_freemoptions(imo);
#endif
}

/*
 * Different protocols initialize their inpcbs differently - giving
 * different name to the lock.  But they all are disposed the same.
 */
static void
inpcb_fini(void *mem, int size)
{
        struct inpcb *inp = mem;

        INP_LOCK_DESTROY(inp);
}

/*
 * in_pcbdrop() removes an inpcb from hashed lists, releasing its address and
 * port reservation, and preventing it from being returned by inpcb lookups.
 *
 * It is used by TCP to mark an inpcb as unused and avoid future packet
 * delivery or event notification when a socket remains open but TCP has
 * closed.  This might occur as a result of a shutdown()-initiated TCP close
 * or a RST on the wire, and allows the port binding to be reused while still
 * maintaining the invariant that so_pcb always points to a valid inpcb until
 * in_pcbdetach().
 *
 * XXXRW: Possibly in_pcbdrop() should also prevent future notifications by
 * in_pcbpurgeif0()?
 */
void
in_pcbdrop(struct inpcb *inp)
{

        INP_WLOCK_ASSERT(inp);

        inp->inp_flags |= INP_DROPPED;
        if (inp->inp_flags & INP_INHASHLIST)
                in_pcbremhash(inp);
}

#ifdef INET
/*
 * Common routines to return the socket addresses associated with inpcbs.
 */
int
in_getsockaddr(struct socket *so, struct sockaddr *sa)
{
        struct inpcb *inp;

        inp = sotoinpcb(so);
        KASSERT(inp != NULL, ("in_getsockaddr: inp == NULL"));

        *(struct sockaddr_in *)sa = (struct sockaddr_in ){
                .sin_len = sizeof(struct sockaddr_in),
                .sin_family = AF_INET,
                .sin_port = inp->inp_lport,
                .sin_addr = inp->inp_laddr,
        };

        return (0);
}

int
in_getpeeraddr(struct socket *so, struct sockaddr *sa)
{
        struct inpcb *inp;

        inp = sotoinpcb(so);
        KASSERT(inp != NULL, ("in_getpeeraddr: inp == NULL"));

        *(struct sockaddr_in *)sa = (struct sockaddr_in ){
                .sin_len = sizeof(struct sockaddr_in),
                .sin_family = AF_INET,
                .sin_port = inp->inp_fport,
                .sin_addr = inp->inp_faddr,
        };

        return (0);
}

static bool
inp_v4_multi_match(const struct inpcb *inp, void *v __unused)
{

        if ((inp->inp_vflag & INP_IPV4) && inp->inp_moptions != NULL)
                return (true);
        else
                return (false);
}

void
in_pcbpurgeif0(struct inpcbinfo *pcbinfo, struct ifnet *ifp)
{
        struct inpcb_iterator inpi = INP_ITERATOR(pcbinfo, INPLOOKUP_WLOCKPCB,
            inp_v4_multi_match, NULL);
        struct inpcb *inp;
        struct in_multi *inm;
        struct in_mfilter *imf;
        struct ip_moptions *imo;

        IN_MULTI_LOCK_ASSERT();

        while ((inp = inp_next(&inpi)) != NULL) {
                INP_WLOCK_ASSERT(inp);

                imo = inp->inp_moptions;
                /*
                 * Unselect the outgoing interface if it is being
                 * detached.
                 */
                if (imo->imo_multicast_ifp == ifp)
                        imo->imo_multicast_ifp = NULL;

                /*
                 * Drop multicast group membership if we joined
                 * through the interface being detached.
                 *
                 * XXX This can all be deferred to an epoch_call
                 */
restart:
                IP_MFILTER_FOREACH(imf, &imo->imo_head) {
                        if ((inm = imf->imf_inm) == NULL)
                                continue;
                        if (inm->inm_ifp != ifp)
                                continue;
                        ip_mfilter_remove(&imo->imo_head, imf);
                        in_leavegroup_locked(inm, NULL);
                        ip_mfilter_free(imf);
                        goto restart;
                }
        }
}

/*
 * Lookup a PCB based on the local address and port.  Caller must hold the
 * hash lock.  No inpcb locks or references are acquired.
 */
#define INP_LOOKUP_MAPPED_PCB_COST      3
struct inpcb *
in_pcblookup_local(struct inpcbinfo *pcbinfo, struct in_addr laddr,
    u_short lport, int fib, int lookupflags, struct ucred *cred)
{
        struct inpcb *inp;
#ifdef INET6
        int matchwild = 3 + INP_LOOKUP_MAPPED_PCB_COST;
#else
        int matchwild = 3;
#endif
        int wildcard;

        KASSERT((lookupflags & ~(INPLOOKUP_WILDCARD)) == 0,
            ("%s: invalid lookup flags %d", __func__, lookupflags));
        KASSERT(fib == RT_ALL_FIBS || (fib >= 0 && fib < V_rt_numfibs),
            ("%s: invalid fib %d", __func__, fib));

        INP_HASH_LOCK_ASSERT(pcbinfo);

        if ((lookupflags & INPLOOKUP_WILDCARD) == 0) {
                struct inpcbhead *head;
                /*
                 * Look for an unconnected (wildcard foreign addr) PCB that
                 * matches the local address and port we're looking for.
                 */
                head = &pcbinfo->ipi_hash_wild[INP_PCBHASH_WILD(lport,
                    pcbinfo->ipi_hashmask)];
                CK_LIST_FOREACH(inp, head, inp_hash_wild) {
#ifdef INET6
                        /* XXX inp locking */
                        if ((inp->inp_vflag & INP_IPV4) == 0)
                                continue;
#endif
                        if (inp->inp_faddr.s_addr == INADDR_ANY &&
                            inp->inp_laddr.s_addr == laddr.s_addr &&
                            inp->inp_lport == lport && (fib == RT_ALL_FIBS ||
                            inp->inp_inc.inc_fibnum == fib)) {
                                /*
                                 * Found?
                                 */
                                if (prison_equal_ip4(cred->cr_prison,
                                    inp->inp_cred->cr_prison))
                                        return (inp);
                        }
                }
                /*
                 * Not found.
                 */
                return (NULL);
        } else {
                struct inpcbhead *porthash;
                struct inpcb *match = NULL;

                /*
                 * Port is in use by one or more PCBs. Look for best
                 * fit.
                 */
                porthash = &pcbinfo->ipi_porthashbase[INP_PCBPORTHASH(lport,
                    pcbinfo->ipi_porthashmask)];
                CK_LIST_FOREACH(inp, porthash, inp_portlist) {
                        if (inp->inp_lport != lport)
                                continue;
                        if (!prison_equal_ip4(inp->inp_cred->cr_prison,
                            cred->cr_prison))
                                continue;
                        if (fib != RT_ALL_FIBS &&
                            inp->inp_inc.inc_fibnum != fib)
                                continue;
                        wildcard = 0;
#ifdef INET6
                        /* XXX inp locking */
                        if ((inp->inp_vflag & INP_IPV4) == 0)
                                continue;
                        /*
                         * We never select the PCB that has INP_IPV6 flag and
                         * is bound to :: if we have another PCB which is bound
                         * to 0.0.0.0.  If a PCB has the INP_IPV6 flag, then we
                         * set its cost higher than IPv4 only PCBs.
                         *
                         * Note that the case only happens when a socket is
                         * bound to ::, under the condition that the use of the
                         * mapped address is allowed.
                         */
                        if ((inp->inp_vflag & INP_IPV6) != 0)
                                wildcard += INP_LOOKUP_MAPPED_PCB_COST;
#endif
                        if (inp->inp_faddr.s_addr != INADDR_ANY)
                                wildcard++;
                        if (inp->inp_laddr.s_addr != INADDR_ANY) {
                                if (laddr.s_addr == INADDR_ANY)
                                        wildcard++;
                                else if (inp->inp_laddr.s_addr != laddr.s_addr)
                                        continue;
                        } else {
                                if (laddr.s_addr != INADDR_ANY)
                                        wildcard++;
                        }
                        if (wildcard < matchwild) {
                                match = inp;
                                matchwild = wildcard;
                                if (matchwild == 0)
                                        break;
                        }
                }
                return (match);
        }
}
#undef INP_LOOKUP_MAPPED_PCB_COST

static bool
in_pcblookup_lb_match(const struct inpcblbgroup *grp, int domain, int fib)
{
        return ((domain == M_NODOM || domain == grp->il_numa_domain) &&
            (fib == RT_ALL_FIBS || fib == grp->il_fibnum));
}

static struct inpcb *
in_pcblookup_lbgroup(const struct inpcbinfo *pcbinfo,
    const struct in_addr *faddr, uint16_t fport, const struct in_addr *laddr,
    uint16_t lport, int domain, int fib)
{
        const struct inpcblbgrouphead *hdr;
        struct inpcblbgroup *grp;
        struct inpcblbgroup *jail_exact, *jail_wild, *local_exact, *local_wild;
        struct inpcb *inp;
        u_int count;

        INP_HASH_LOCK_ASSERT(pcbinfo);
        NET_EPOCH_ASSERT();

        hdr = &pcbinfo->ipi_lbgrouphashbase[
            INP_PCBPORTHASH(lport, pcbinfo->ipi_lbgrouphashmask)];

        /*
         * Search for an LB group match based on the following criteria:
         * - prefer jailed groups to non-jailed groups
         * - prefer exact source address matches to wildcard matches
         * - prefer groups bound to the specified NUMA domain
         */
        jail_exact = jail_wild = local_exact = local_wild = NULL;
        CK_LIST_FOREACH(grp, hdr, il_list) {
                bool injail;

#ifdef INET6
                if (!(grp->il_vflag & INP_IPV4))
                        continue;
#endif
                if (grp->il_lport != lport)
                        continue;

                injail = prison_flag(grp->il_cred, PR_IP4) != 0;
                if (injail && prison_check_ip4_locked(grp->il_cred->cr_prison,
                    laddr) != 0)
                        continue;

                if (grp->il_laddr.s_addr == laddr->s_addr) {
                        if (injail) {
                                jail_exact = grp;
                                if (in_pcblookup_lb_match(grp, domain, fib))
                                        /* This is a perfect match. */
                                        goto out;
                        } else if (local_exact == NULL ||
                            in_pcblookup_lb_match(grp, domain, fib)) {
                                local_exact = grp;
                        }
                } else if (grp->il_laddr.s_addr == INADDR_ANY) {
                        if (injail) {
                                if (jail_wild == NULL ||
                                    in_pcblookup_lb_match(grp, domain, fib))
                                        jail_wild = grp;
                        } else if (local_wild == NULL ||
                            in_pcblookup_lb_match(grp, domain, fib)) {
                                local_wild = grp;
                        }
                }
        }

        if (jail_exact != NULL)
                grp = jail_exact;
        else if (jail_wild != NULL)
                grp = jail_wild;
        else if (local_exact != NULL)
                grp = local_exact;
        else
                grp = local_wild;
        if (grp == NULL)
                return (NULL);

out:
        /*
         * Synchronize with in_pcblbgroup_insert().
         */
        count = atomic_load_acq_int(&grp->il_inpcnt);
        if (count == 0)
                return (NULL);
        inp = grp->il_inp[INP_PCBLBGROUP_PKTHASH(faddr, lport, fport) % count];
        KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
        return (inp);
}

static bool
in_pcblookup_exact_match(const struct inpcb *inp, struct in_addr faddr,
    u_short fport, struct in_addr laddr, u_short lport)
{
#ifdef INET6
        /* XXX inp locking */
        if ((inp->inp_vflag & INP_IPV4) == 0)
                return (false);
#endif
        if (inp->inp_faddr.s_addr == faddr.s_addr &&
            inp->inp_laddr.s_addr == laddr.s_addr &&
            inp->inp_fport == fport &&
            inp->inp_lport == lport)
                return (true);
        return (false);
}

static struct inpcb *
in_pcblookup_hash_exact(struct inpcbinfo *pcbinfo, struct in_addr faddr,
    u_short fport, struct in_addr laddr, u_short lport)
{
        struct inpcbhead *head;
        struct inpcb *inp;

        INP_HASH_LOCK_ASSERT(pcbinfo);

        head = &pcbinfo->ipi_hash_exact[INP_PCBHASH(&faddr, lport, fport,
            pcbinfo->ipi_hashmask)];
        CK_LIST_FOREACH(inp, head, inp_hash_exact) {
                if (in_pcblookup_exact_match(inp, faddr, fport, laddr, lport))
                        return (inp);
        }
        return (NULL);
}

typedef enum {
        INPLOOKUP_MATCH_NONE = 0,
        INPLOOKUP_MATCH_WILD = 1,
        INPLOOKUP_MATCH_LADDR = 2,
} inp_lookup_match_t;

static inp_lookup_match_t
in_pcblookup_wild_match(const struct inpcb *inp, struct in_addr laddr,
    u_short lport, int fib)
{
#ifdef INET6
        /* XXX inp locking */
        if ((inp->inp_vflag & INP_IPV4) == 0)
                return (INPLOOKUP_MATCH_NONE);
#endif
        if (inp->inp_faddr.s_addr != INADDR_ANY || inp->inp_lport != lport)
                return (INPLOOKUP_MATCH_NONE);
        if (fib != RT_ALL_FIBS && inp->inp_inc.inc_fibnum != fib)
                return (INPLOOKUP_MATCH_NONE);
        if (inp->inp_laddr.s_addr == INADDR_ANY)
                return (INPLOOKUP_MATCH_WILD);
        if (inp->inp_laddr.s_addr == laddr.s_addr)
                return (INPLOOKUP_MATCH_LADDR);
        return (INPLOOKUP_MATCH_NONE);
}

#define INP_LOOKUP_AGAIN        ((struct inpcb *)(uintptr_t)-1)

static struct inpcb *
in_pcblookup_hash_wild_smr(struct inpcbinfo *pcbinfo, struct in_addr laddr,
    u_short lport, int fib, const inp_lookup_t lockflags)
{
        struct inpcbhead *head;
        struct inpcb *inp;

        KASSERT(SMR_ENTERED(pcbinfo->ipi_smr),
            ("%s: not in SMR read section", __func__));

        head = &pcbinfo->ipi_hash_wild[INP_PCBHASH_WILD(lport,
            pcbinfo->ipi_hashmask)];
        CK_LIST_FOREACH(inp, head, inp_hash_wild) {
                inp_lookup_match_t match;

                match = in_pcblookup_wild_match(inp, laddr, lport, fib);
                if (match == INPLOOKUP_MATCH_NONE)
                        continue;

                if (__predict_true(inp_smr_lock(inp, lockflags))) {
                        match = in_pcblookup_wild_match(inp, laddr, lport, fib);
                        if (match != INPLOOKUP_MATCH_NONE &&
                            prison_check_ip4_locked(inp->inp_cred->cr_prison,
                            &laddr) == 0)
                                return (inp);
                        inp_unlock(inp, lockflags);
                }

                /*
                 * The matching socket disappeared out from under us.  Fall back
                 * to a serialized lookup.
                 */
                return (INP_LOOKUP_AGAIN);
        }
        return (NULL);
}

static struct inpcb *
in_pcblookup_hash_wild_locked(struct inpcbinfo *pcbinfo, struct in_addr laddr,
    u_short lport, int fib)
{
        struct inpcbhead *head;
        struct inpcb *inp, *local_wild, *local_exact, *jail_wild;
#ifdef INET6
        struct inpcb *local_wild_mapped;
#endif

        INP_HASH_LOCK_ASSERT(pcbinfo);

        /*
         * Order of socket selection - we always prefer jails.
         *      1. jailed, non-wild.
         *      2. jailed, wild.
         *      3. non-jailed, non-wild.
         *      4. non-jailed, wild.
         */
        head = &pcbinfo->ipi_hash_wild[INP_PCBHASH_WILD(lport,
            pcbinfo->ipi_hashmask)];
        local_wild = local_exact = jail_wild = NULL;
#ifdef INET6
        local_wild_mapped = NULL;
#endif
        CK_LIST_FOREACH(inp, head, inp_hash_wild) {
                inp_lookup_match_t match;
                bool injail;

                match = in_pcblookup_wild_match(inp, laddr, lport, fib);
                if (match == INPLOOKUP_MATCH_NONE)
                        continue;

                injail = prison_flag(inp->inp_cred, PR_IP4) != 0;
                if (injail) {
                        if (prison_check_ip4_locked(inp->inp_cred->cr_prison,
                            &laddr) != 0)
                                continue;
                } else {
                        if (local_exact != NULL)
                                continue;
                }

                if (match == INPLOOKUP_MATCH_LADDR) {
                        if (injail)
                                return (inp);
                        local_exact = inp;
                } else {
#ifdef INET6
                        /* XXX inp locking, NULL check */
                        if (inp->inp_vflag & INP_IPV6PROTO)
                                local_wild_mapped = inp;
                        else
#endif
                                if (injail)
                                        jail_wild = inp;
                                else
                                        local_wild = inp;
                }
        }
        if (jail_wild != NULL)
                return (jail_wild);
        if (local_exact != NULL)
                return (local_exact);
        if (local_wild != NULL)
                return (local_wild);
#ifdef INET6
        if (local_wild_mapped != NULL)
                return (local_wild_mapped);
#endif
        return (NULL);
}

/*
 * Lookup PCB in hash list, using pcbinfo tables.  This variation assumes
 * that the caller has either locked the hash list, which usually happens
 * for bind(2) operations, or is in SMR section, which happens when sorting
 * out incoming packets.
 */
static struct inpcb *
in_pcblookup_hash_locked(struct inpcbinfo *pcbinfo, struct in_addr faddr,
    u_int fport_arg, struct in_addr laddr, u_int lport_arg, int lookupflags,
    uint8_t numa_domain, int fib)
{
        struct inpcb *inp;
        const u_short fport = fport_arg, lport = lport_arg;

        KASSERT((lookupflags & ~(INPLOOKUP_WILDCARD | INPLOOKUP_FIB)) == 0,
            ("%s: invalid lookup flags %d", __func__, lookupflags));
        KASSERT(faddr.s_addr != INADDR_ANY,
            ("%s: invalid foreign address", __func__));
        KASSERT(laddr.s_addr != INADDR_ANY,
            ("%s: invalid local address", __func__));
        INP_HASH_WLOCK_ASSERT(pcbinfo);

        inp = in_pcblookup_hash_exact(pcbinfo, faddr, fport, laddr, lport);
        if (inp != NULL)
                return (inp);

        if ((lookupflags & INPLOOKUP_WILDCARD) != 0) {
                inp = in_pcblookup_lbgroup(pcbinfo, &faddr, fport,
                    &laddr, lport, numa_domain, fib);
                if (inp == NULL) {
                        inp = in_pcblookup_hash_wild_locked(pcbinfo, laddr,
                            lport, fib);
                }
        }

        return (inp);
}

static struct inpcb *
in_pcblookup_hash(struct inpcbinfo *pcbinfo, struct in_addr faddr,
    u_int fport, struct in_addr laddr, u_int lport, int lookupflags,
    uint8_t numa_domain, int fib)
{
        struct inpcb *inp;
        const inp_lookup_t lockflags = lookupflags & INPLOOKUP_LOCKMASK;

        KASSERT((lookupflags & (INPLOOKUP_RLOCKPCB | INPLOOKUP_WLOCKPCB)) != 0,
            ("%s: LOCKPCB not set", __func__));

        INP_HASH_WLOCK(pcbinfo);
        inp = in_pcblookup_hash_locked(pcbinfo, faddr, fport, laddr, lport,
            lookupflags & ~INPLOOKUP_LOCKMASK, numa_domain, fib);
        if (inp != NULL && !inp_trylock(inp, lockflags)) {
                in_pcbref(inp);
                INP_HASH_WUNLOCK(pcbinfo);
                inp_lock(inp, lockflags);
                if (in_pcbrele(inp, lockflags))
                        /* XXX-MJ or retry until we get a negative match? */
                        inp = NULL;
        } else {
                INP_HASH_WUNLOCK(pcbinfo);
        }
        return (inp);
}

static struct inpcb *
in_pcblookup_hash_smr(struct inpcbinfo *pcbinfo, struct in_addr faddr,
    u_int fport_arg, struct in_addr laddr, u_int lport_arg, int lookupflags,
    uint8_t numa_domain, int fib)
{
        struct inpcb *inp;
        const inp_lookup_t lockflags = lookupflags & INPLOOKUP_LOCKMASK;
        const u_short fport = fport_arg, lport = lport_arg;

        KASSERT((lookupflags & ~INPLOOKUP_MASK) == 0,
            ("%s: invalid lookup flags %d", __func__, lookupflags));
        KASSERT((lookupflags & (INPLOOKUP_RLOCKPCB | INPLOOKUP_WLOCKPCB)) != 0,
            ("%s: LOCKPCB not set", __func__));

        smr_enter(pcbinfo->ipi_smr);
        inp = in_pcblookup_hash_exact(pcbinfo, faddr, fport, laddr, lport);
        if (inp != NULL) {
                if (__predict_true(inp_smr_lock(inp, lockflags))) {
                        /*
                         * Revalidate the 4-tuple, the socket could have been
                         * disconnected.
                         */
                        if (__predict_true(in_pcblookup_exact_match(inp,
                            faddr, fport, laddr, lport)))
                                return (inp);
                        inp_unlock(inp, lockflags);
                }

                /*
                 * We failed to lock the inpcb, or its connection state changed
                 * out from under us.  Fall back to a precise search.
                 */
                return (in_pcblookup_hash(pcbinfo, faddr, fport, laddr, lport,
                    lookupflags, numa_domain, fib));
        }

        if ((lookupflags & INPLOOKUP_WILDCARD) != 0) {
                inp = in_pcblookup_lbgroup(pcbinfo, &faddr, fport,
                    &laddr, lport, numa_domain, fib);
                if (inp != NULL) {
                        if (__predict_true(inp_smr_lock(inp, lockflags))) {
                                if (__predict_true(in_pcblookup_wild_match(inp,
                                    laddr, lport, fib) != INPLOOKUP_MATCH_NONE))
                                        return (inp);
                                inp_unlock(inp, lockflags);
                        }
                        inp = INP_LOOKUP_AGAIN;
                } else {
                        inp = in_pcblookup_hash_wild_smr(pcbinfo, laddr, lport,
                            fib, lockflags);
                }
                if (inp == INP_LOOKUP_AGAIN) {
                        return (in_pcblookup_hash(pcbinfo, faddr, fport, laddr,
                            lport, lookupflags, numa_domain, fib));
                }
        }

        if (inp == NULL)
                smr_exit(pcbinfo->ipi_smr);

        return (inp);
}

/*
 * Public inpcb lookup routines, accepting a 4-tuple, and optionally, an mbuf
 * from which a pre-calculated hash value may be extracted.
 */
struct inpcb *
in_pcblookup(struct inpcbinfo *pcbinfo, struct in_addr faddr, u_int fport,
    struct in_addr laddr, u_int lport, int lookupflags,
    struct ifnet *ifp)
{
        int fib;

        fib = (lookupflags & INPLOOKUP_FIB) ? if_getfib(ifp) : RT_ALL_FIBS;
        return (in_pcblookup_hash_smr(pcbinfo, faddr, fport, laddr, lport,
            lookupflags, M_NODOM, fib));
}

struct inpcb *
in_pcblookup_mbuf(struct inpcbinfo *pcbinfo, struct in_addr faddr,
    u_int fport, struct in_addr laddr, u_int lport, int lookupflags,
    struct ifnet *ifp __unused, struct mbuf *m)
{
        int fib;

        M_ASSERTPKTHDR(m);
        fib = (lookupflags & INPLOOKUP_FIB) ? M_GETFIB(m) : RT_ALL_FIBS;
        return (in_pcblookup_hash_smr(pcbinfo, faddr, fport, laddr, lport,
            lookupflags, m->m_pkthdr.numa_domain, fib));
}
#endif /* INET */

static bool
in_pcbjailed(const struct inpcb *inp, unsigned int flag)
{
        return (prison_flag(inp->inp_cred, flag) != 0);
}

/*
 * Insert the PCB into a hash chain using ordering rules which ensure that
 * in_pcblookup_hash_wild_*() always encounter the highest-ranking PCB first.
 *
 * Specifically, keep jailed PCBs in front of non-jailed PCBs, and keep PCBs
 * with exact local addresses ahead of wildcard PCBs.  Unbound v4-mapped v6 PCBs
 * always appear last no matter whether they are jailed.
 */
static void
_in_pcbinshash_wild(struct inpcbhead *pcbhash, struct inpcb *inp)
{
        struct inpcb *last;
        bool bound, injail;

        INP_LOCK_ASSERT(inp);
        INP_HASH_WLOCK_ASSERT(inp->inp_pcbinfo);

        last = NULL;
        bound = inp->inp_laddr.s_addr != INADDR_ANY;
        if (!bound && (inp->inp_vflag & INP_IPV6PROTO) != 0) {
                CK_LIST_FOREACH(last, pcbhash, inp_hash_wild) {
                        if (CK_LIST_NEXT(last, inp_hash_wild) == NULL) {
                                CK_LIST_INSERT_AFTER(last, inp, inp_hash_wild);
                                return;
                        }
                }
                CK_LIST_INSERT_HEAD(pcbhash, inp, inp_hash_wild);
                return;
        }

        injail = in_pcbjailed(inp, PR_IP4);
        if (!injail) {
                CK_LIST_FOREACH(last, pcbhash, inp_hash_wild) {
                        if (!in_pcbjailed(last, PR_IP4))
                                break;
                        if (CK_LIST_NEXT(last, inp_hash_wild) == NULL) {
                                CK_LIST_INSERT_AFTER(last, inp, inp_hash_wild);
                                return;
                        }
                }
        } else if (!CK_LIST_EMPTY(pcbhash) &&
            !in_pcbjailed(CK_LIST_FIRST(pcbhash), PR_IP4)) {
                CK_LIST_INSERT_HEAD(pcbhash, inp, inp_hash_wild);
                return;
        }
        if (!bound) {
                CK_LIST_FOREACH_FROM(last, pcbhash, inp_hash_wild) {
                        if (last->inp_laddr.s_addr == INADDR_ANY)
                                break;
                        if (CK_LIST_NEXT(last, inp_hash_wild) == NULL) {
                                CK_LIST_INSERT_AFTER(last, inp, inp_hash_wild);
                                return;
                        }
                }
        }
        if (last == NULL)
                CK_LIST_INSERT_HEAD(pcbhash, inp, inp_hash_wild);
        else
                CK_LIST_INSERT_BEFORE(last, inp, inp_hash_wild);
}

#ifdef INET6
/*
 * See the comment above _in_pcbinshash_wild().
 */
static void
_in6_pcbinshash_wild(struct inpcbhead *pcbhash, struct inpcb *inp)
{
        struct inpcb *last;
        bool bound, injail;

        INP_LOCK_ASSERT(inp);
        INP_HASH_WLOCK_ASSERT(inp->inp_pcbinfo);

        last = NULL;
        bound = !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr);
        injail = in_pcbjailed(inp, PR_IP6);
        if (!injail) {
                CK_LIST_FOREACH(last, pcbhash, inp_hash_wild) {
                        if (!in_pcbjailed(last, PR_IP6))
                                break;
                        if (CK_LIST_NEXT(last, inp_hash_wild) == NULL) {
                                CK_LIST_INSERT_AFTER(last, inp, inp_hash_wild);
                                return;
                        }
                }
        } else if (!CK_LIST_EMPTY(pcbhash) &&
            !in_pcbjailed(CK_LIST_FIRST(pcbhash), PR_IP6)) {
                CK_LIST_INSERT_HEAD(pcbhash, inp, inp_hash_wild);
                return;
        }
        if (!bound) {
                CK_LIST_FOREACH_FROM(last, pcbhash, inp_hash_wild) {
                        if (IN6_IS_ADDR_UNSPECIFIED(&last->in6p_laddr))
                                break;
                        if (CK_LIST_NEXT(last, inp_hash_wild) == NULL) {
                                CK_LIST_INSERT_AFTER(last, inp, inp_hash_wild);
                                return;
                        }
                }
        }
        if (last == NULL)
                CK_LIST_INSERT_HEAD(pcbhash, inp, inp_hash_wild);
        else
                CK_LIST_INSERT_BEFORE(last, inp, inp_hash_wild);
}
#endif

/*
 * Insert PCB onto various hash lists.
 *
 * With normal sockets this function shall not fail, so it could return void.
 * But for SO_REUSEPORT_LB it may need to allocate memory with locks held,
 * that's the only condition when it can fail.
 */
int
in_pcbinshash(struct inpcb *inp)
{
        struct inpcbhead *pcbhash, *pcbporthash;
        struct inpcbinfo *pcbinfo = inp->inp_pcbinfo;
        uint32_t hash;
        bool connected;

        INP_WLOCK_ASSERT(inp);
        INP_HASH_WLOCK_ASSERT(pcbinfo);
        KASSERT((inp->inp_flags & INP_INHASHLIST) == 0,
            ("in_pcbinshash: INP_INHASHLIST"));

#ifdef INET6
        if (inp->inp_vflag & INP_IPV6) {
                hash = INP6_PCBHASH(&inp->in6p_faddr, inp->inp_lport,
                    inp->inp_fport, pcbinfo->ipi_hashmask);
                connected = !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr);
        } else
#endif
        {
                hash = INP_PCBHASH(&inp->inp_faddr, inp->inp_lport,
                    inp->inp_fport, pcbinfo->ipi_hashmask);
                connected = !in_nullhost(inp->inp_faddr);
        }

        if (connected)
                pcbhash = &pcbinfo->ipi_hash_exact[hash];
        else
                pcbhash = &pcbinfo->ipi_hash_wild[hash];

        pcbporthash = &pcbinfo->ipi_porthashbase[
            INP_PCBPORTHASH(inp->inp_lport, pcbinfo->ipi_porthashmask)];

        /*
         * Ignore SO_REUSEPORT_LB if the socket is connected.  Really this case
         * should be an error, but for UDP sockets it is not, and some
         * applications erroneously set it on connected UDP sockets, so we can't
         * change this without breaking compatibility.
         */
        if (!connected &&
            (inp->inp_socket->so_options & SO_REUSEPORT_LB) != 0) {
                int error = in_pcbinslbgrouphash(inp, M_NODOM);
                if (error != 0)
                        return (error);
        }

        /*
         * The PCB may have been disconnected in the past.  Before we can safely
         * make it visible in the hash table, we must wait for all readers which
         * may be traversing this PCB to finish.
         */
        if (inp->inp_smr != SMR_SEQ_INVALID) {
                smr_wait(pcbinfo->ipi_smr, inp->inp_smr);
                inp->inp_smr = SMR_SEQ_INVALID;
        }

        if (connected)
                CK_LIST_INSERT_HEAD(pcbhash, inp, inp_hash_exact);
        else {
#ifdef INET6
                if ((inp->inp_vflag & INP_IPV6) != 0)
                        _in6_pcbinshash_wild(pcbhash, inp);
                else
#endif
                        _in_pcbinshash_wild(pcbhash, inp);
        }
        CK_LIST_INSERT_HEAD(pcbporthash, inp, inp_portlist);
        inp->inp_flags |= INP_INHASHLIST;

        return (0);
}

void
in_pcbremhash_locked(struct inpcb *inp)
{

        INP_WLOCK_ASSERT(inp);
        INP_HASH_WLOCK_ASSERT(inp->inp_pcbinfo);
        MPASS(inp->inp_flags & INP_INHASHLIST);

        if ((inp->inp_flags & INP_INLBGROUP) != 0)
                in_pcbremlbgrouphash(inp);
#ifdef INET6
        if (inp->inp_vflag & INP_IPV6) {
                if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr))
                        CK_LIST_REMOVE(inp, inp_hash_wild);
                else
                        CK_LIST_REMOVE(inp, inp_hash_exact);
        } else
#endif
        {
                if (in_nullhost(inp->inp_faddr))
                        CK_LIST_REMOVE(inp, inp_hash_wild);
                else
                        CK_LIST_REMOVE(inp, inp_hash_exact);
        }
        CK_LIST_REMOVE(inp, inp_portlist);
        inp->inp_flags &= ~INP_INHASHLIST;
}

static void
in_pcbremhash(struct inpcb *inp)
{
        INP_HASH_WLOCK(inp->inp_pcbinfo);
        in_pcbremhash_locked(inp);
        INP_HASH_WUNLOCK(inp->inp_pcbinfo);
}

/*
 * Move PCB to the proper hash bucket when { faddr, fport } have  been
 * changed. NOTE: This does not handle the case of the lport changing (the
 * hashed port list would have to be updated as well), so the lport must
 * not change after in_pcbinshash() has been called.
 */
void
in_pcbrehash(struct inpcb *inp)
{
        struct inpcbinfo *pcbinfo = inp->inp_pcbinfo;
        struct inpcbhead *head;
        uint32_t hash;
        bool connected;

        INP_WLOCK_ASSERT(inp);
        INP_HASH_WLOCK_ASSERT(pcbinfo);
        KASSERT(inp->inp_flags & INP_INHASHLIST,
            ("%s: !INP_INHASHLIST", __func__));
        KASSERT(inp->inp_smr == SMR_SEQ_INVALID,
            ("%s: inp was disconnected", __func__));

#ifdef INET6
        if (inp->inp_vflag & INP_IPV6) {
                hash = INP6_PCBHASH(&inp->in6p_faddr, inp->inp_lport,
                    inp->inp_fport, pcbinfo->ipi_hashmask);
                connected = !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr);
        } else
#endif
        {
                hash = INP_PCBHASH(&inp->inp_faddr, inp->inp_lport,
                    inp->inp_fport, pcbinfo->ipi_hashmask);
                connected = !in_nullhost(inp->inp_faddr);
        }

        /* See the comment in in_pcbinshash(). */
        if (connected && (inp->inp_flags & INP_INLBGROUP) != 0)
                in_pcbremlbgrouphash(inp);

        /*
         * When rehashing, the caller must ensure that either the new or the old
         * foreign address was unspecified.
         */
        if (connected)
                CK_LIST_REMOVE(inp, inp_hash_wild);
        else
                CK_LIST_REMOVE(inp, inp_hash_exact);

        if (connected) {
                head = &pcbinfo->ipi_hash_exact[hash];
                CK_LIST_INSERT_HEAD(head, inp, inp_hash_exact);
        } else {
                head = &pcbinfo->ipi_hash_wild[hash];
                CK_LIST_INSERT_HEAD(head, inp, inp_hash_wild);
        }
}

/*
 * Check for alternatives when higher level complains
 * about service problems.  For now, invalidate cached
 * routing information.  If the route was created dynamically
 * (by a redirect), time to try a default gateway again.
 */
void
in_losing(struct inpcb *inp)
{

        RO_INVALIDATE_CACHE(&inp->inp_route);
        return;
}

/*
 * A set label operation has occurred at the socket layer, propagate the
 * label change into the in_pcb for the socket.
 */
void
in_pcbsosetlabel(struct socket *so)
{
#ifdef MAC
        struct inpcb *inp;

        inp = sotoinpcb(so);
        KASSERT(inp != NULL, ("in_pcbsosetlabel: so->so_pcb == NULL"));

        INP_WLOCK(inp);
        SOCK_LOCK(so);
        mac_inpcb_sosetlabel(so, inp);
        SOCK_UNLOCK(so);
        INP_WUNLOCK(inp);
#endif
}

void
inp_wlock(struct inpcb *inp)
{

        INP_WLOCK(inp);
}

void
inp_wunlock(struct inpcb *inp)
{

        INP_WUNLOCK(inp);
}

void
inp_rlock(struct inpcb *inp)
{

        INP_RLOCK(inp);
}

void
inp_runlock(struct inpcb *inp)
{

        INP_RUNLOCK(inp);
}

#ifdef INVARIANT_SUPPORT
void
inp_lock_assert(struct inpcb *inp)
{

        INP_WLOCK_ASSERT(inp);
}

void
inp_unlock_assert(struct inpcb *inp)
{

        INP_UNLOCK_ASSERT(inp);
}
#endif

void
inp_apply_all(struct inpcbinfo *pcbinfo,
    void (*func)(struct inpcb *, void *), void *arg)
{
        struct inpcb_iterator inpi = INP_ALL_ITERATOR(pcbinfo,
            INPLOOKUP_WLOCKPCB);
        struct inpcb *inp;

        while ((inp = inp_next(&inpi)) != NULL)
                func(inp, arg);
}

struct socket *
inp_inpcbtosocket(struct inpcb *inp)
{

        INP_WLOCK_ASSERT(inp);
        return (inp->inp_socket);
}

void
inp_4tuple_get(struct inpcb *inp, uint32_t *laddr, uint16_t *lp,
    uint32_t *faddr, uint16_t *fp)
{

        INP_LOCK_ASSERT(inp);
        *laddr = inp->inp_laddr.s_addr;
        *faddr = inp->inp_faddr.s_addr;
        *lp = inp->inp_lport;
        *fp = inp->inp_fport;
}

/*
 * Create an external-format (``xinpcb'') structure using the information in
 * the kernel-format in_pcb structure pointed to by inp.  This is done to
 * reduce the spew of irrelevant information over this interface, to isolate
 * user code from changes in the kernel structure, and potentially to provide
 * information-hiding if we decide that some of this information should be
 * hidden from users.
 */
void
in_pcbtoxinpcb(const struct inpcb *inp, struct xinpcb *xi)
{

        bzero(xi, sizeof(*xi));
        xi->xi_len = sizeof(struct xinpcb);
        if (inp->inp_socket)
                sotoxsocket(inp->inp_socket, &xi->xi_socket);
        bcopy(&inp->inp_inc, &xi->inp_inc, sizeof(struct in_conninfo));
        xi->inp_gencnt = inp->inp_gencnt;
        xi->inp_flow = inp->inp_flow;
        xi->inp_flowid = inp->inp_flowid;
        xi->inp_flowtype = inp->inp_flowtype;
        xi->inp_flags = inp->inp_flags;
        xi->inp_flags2 = inp->inp_flags2;
        xi->in6p_cksum = inp->in6p_cksum;
        xi->in6p_hops = inp->in6p_hops;
        xi->inp_ip_tos = inp->inp_ip_tos;
        xi->inp_vflag = inp->inp_vflag;
        xi->inp_ip_ttl = inp->inp_ip_ttl;
        xi->inp_ip_p = inp->inp_ip_p;
        xi->inp_ip_minttl = inp->inp_ip_minttl;
}

int
sysctl_setsockopt(SYSCTL_HANDLER_ARGS, struct inpcbinfo *pcbinfo,
    int (*ctloutput_set)(struct inpcb *, struct sockopt *))
{
        struct sockopt sopt;
        struct inpcb_iterator inpi = INP_ALL_ITERATOR(pcbinfo,
            INPLOOKUP_WLOCKPCB);
        struct inpcb *inp;
        struct sockopt_parameters *params;
        struct socket *so;
        int error;
        char buf[1024];

        if (req->oldptr != NULL || req->oldlen != 0)
                return (EINVAL);
        if (req->newptr == NULL)
                return (EPERM);
        if (req->newlen > sizeof(buf))
                return (ENOMEM);
        error = SYSCTL_IN(req, buf, req->newlen);
        if (error != 0)
                return (error);
        if (req->newlen < sizeof(struct sockopt_parameters))
                return (EINVAL);
        params = (struct sockopt_parameters *)buf;
        sopt.sopt_level = params->sop_level;
        sopt.sopt_name = params->sop_optname;
        sopt.sopt_dir = SOPT_SET;
        sopt.sopt_val = params->sop_optval;
        sopt.sopt_valsize = req->newlen - sizeof(struct sockopt_parameters);
        sopt.sopt_td = NULL;
#ifdef INET6
        if (params->sop_inc.inc_flags & INC_ISIPV6) {
                if (IN6_IS_SCOPE_LINKLOCAL(&params->sop_inc.inc6_laddr))
                        params->sop_inc.inc6_laddr.s6_addr16[1] =
                            htons(params->sop_inc.inc6_zoneid & 0xffff);
                if (IN6_IS_SCOPE_LINKLOCAL(&params->sop_inc.inc6_faddr))
                        params->sop_inc.inc6_faddr.s6_addr16[1] =
                            htons(params->sop_inc.inc6_zoneid & 0xffff);
        }
#endif
        if (params->sop_inc.inc_lport != htons(0) &&
            params->sop_inc.inc_fport != htons(0)) {
#ifdef INET6
                if (params->sop_inc.inc_flags & INC_ISIPV6)
                        inpi.hash = INP6_PCBHASH(
                            &params->sop_inc.inc6_faddr,
                            params->sop_inc.inc_lport,
                            params->sop_inc.inc_fport,
                            pcbinfo->ipi_hashmask);
                else
#endif
                        inpi.hash = INP_PCBHASH(
                            &params->sop_inc.inc_faddr,
                            params->sop_inc.inc_lport,
                            params->sop_inc.inc_fport,
                            pcbinfo->ipi_hashmask);
        }
        while ((inp = inp_next(&inpi)) != NULL)
                if (inp->inp_gencnt == params->sop_id) {
                        if (inp->inp_flags & INP_DROPPED) {
                                INP_WUNLOCK(inp);
                                return (ECONNRESET);
                        }
                        so = inp->inp_socket;
                        KASSERT(so != NULL, ("inp_socket == NULL"));
                        soref(so);
                        if (params->sop_level == SOL_SOCKET) {
                                INP_WUNLOCK(inp);
                                error = sosetopt(so, &sopt);
                        } else
                                error = (*ctloutput_set)(inp, &sopt);
                        sorele(so);
                        break;
                }
        if (inp == NULL)
                error = ESRCH;
        return (error);
}

#ifdef DDB
static void
db_print_indent(int indent)
{
        int i;

        for (i = 0; i < indent; i++)
                db_printf(" ");
}

static void
db_print_inconninfo(struct in_conninfo *inc, const char *name, int indent)
{
        char faddr_str[48], laddr_str[48];

        db_print_indent(indent);
        db_printf("%s at %p\n", name, inc);

        indent += 2;

#ifdef INET6
        if (inc->inc_flags & INC_ISIPV6) {
                /* IPv6. */
                ip6_sprintf(laddr_str, &inc->inc6_laddr);
                ip6_sprintf(faddr_str, &inc->inc6_faddr);
        } else
#endif
        {
                /* IPv4. */
                inet_ntoa_r(inc->inc_laddr, laddr_str);
                inet_ntoa_r(inc->inc_faddr, faddr_str);
        }
        db_print_indent(indent);
        db_printf("inc_laddr %s   inc_lport %u\n", laddr_str,
            ntohs(inc->inc_lport));
        db_print_indent(indent);
        db_printf("inc_faddr %s   inc_fport %u\n", faddr_str,
            ntohs(inc->inc_fport));
}

void
db_print_inpcb(struct inpcb *inp, const char *name, int indent)
{

        db_print_indent(indent);
        db_printf("%s at %p\n", name, inp);

        indent += 2;

        db_print_indent(indent);
        db_printf("inp_flow: 0x%x   inp_label: %p\n", inp->inp_flow,
            inp->inp_label);

        db_print_inconninfo(&inp->inp_inc, "inp_conninfo", indent);

        db_print_indent(indent);
        db_printf("inp_flags: 0x%b\n", inp->inp_flags, INP_FLAGS_BITS);

        db_print_indent(indent);
        db_printf("inp_flags2: 0x%b\n", inp->inp_flags2, INP_FLAGS2_BITS);

        db_print_indent(indent);
        db_printf("inp_sp: %p   inp_vflag: 0x%b\n", inp->inp_sp,
            inp->inp_vflag, INP_VFLAGS_BITS);

        db_print_indent(indent);
        db_printf("inp_ip_ttl: %d   inp_ip_p: %d   inp_ip_minttl: %d\n",
            inp->inp_ip_ttl, inp->inp_ip_p, inp->inp_ip_minttl);

#ifdef INET6
        if (inp->inp_vflag & INP_IPV6) {
                db_print_indent(indent);
                db_printf("in6p_options: %p   in6p_outputopts: %p   "
                    "in6p_moptions: %p\n", inp->in6p_options,
                    inp->in6p_outputopts, inp->in6p_moptions);
                db_print_indent(indent);
                db_printf("in6p_icmp6filt: %p   in6p_cksum %d   "
                    "in6p_hops %u\n", inp->in6p_icmp6filt, inp->in6p_cksum,
                    inp->in6p_hops);
        } else
#endif
        {
                db_print_indent(indent);
                db_printf("inp_ip_tos: %d   inp_ip_options: %p   "
                    "inp_ip_moptions: %p\n", inp->inp_ip_tos,
                    inp->inp_options, inp->inp_moptions);
        }

        db_print_indent(indent);
        db_printf("inp_gencnt: %ju\n", (uintmax_t)inp->inp_gencnt);
}

DB_SHOW_COMMAND(inpcb, db_show_inpcb)
{
        struct inpcb *inp;

        if (!have_addr) {
                db_printf("usage: show inpcb <addr>\n");
                return;
        }
        inp = (struct inpcb *)addr;

        db_print_inpcb(inp, "inpcb", 0);
}
#endif /* DDB */

#ifdef RATELIMIT
/*
 * Modify TX rate limit based on the existing "inp->inp_snd_tag",
 * if any.
 */
int
in_pcbmodify_txrtlmt(struct inpcb *inp, uint32_t max_pacing_rate)
{
        union if_snd_tag_modify_params params = {
                .rate_limit.max_rate = max_pacing_rate,
                .rate_limit.flags = M_NOWAIT,
        };
        struct m_snd_tag *mst;
        int error;

        mst = inp->inp_snd_tag;
        if (mst == NULL)
                return (EINVAL);

        if (mst->sw->snd_tag_modify == NULL) {
                error = EOPNOTSUPP;
        } else {
                error = mst->sw->snd_tag_modify(mst, &params);
        }
        return (error);
}

/*
 * Query existing TX rate limit based on the existing
 * "inp->inp_snd_tag", if any.
 */
int
in_pcbquery_txrtlmt(struct inpcb *inp, uint32_t *p_max_pacing_rate)
{
        union if_snd_tag_query_params params = { };
        struct m_snd_tag *mst;
        int error;

        mst = inp->inp_snd_tag;
        if (mst == NULL)
                return (EINVAL);

        if (mst->sw->snd_tag_query == NULL) {
                error = EOPNOTSUPP;
        } else {
                error = mst->sw->snd_tag_query(mst, &params);
                if (error == 0 && p_max_pacing_rate != NULL)
                        *p_max_pacing_rate = params.rate_limit.max_rate;
        }
        return (error);
}

/*
 * Query existing TX queue level based on the existing
 * "inp->inp_snd_tag", if any.
 */
int
in_pcbquery_txrlevel(struct inpcb *inp, uint32_t *p_txqueue_level)
{
        union if_snd_tag_query_params params = { };
        struct m_snd_tag *mst;
        int error;

        mst = inp->inp_snd_tag;
        if (mst == NULL)
                return (EINVAL);

        if (mst->sw->snd_tag_query == NULL)
                return (EOPNOTSUPP);

        error = mst->sw->snd_tag_query(mst, &params);
        if (error == 0 && p_txqueue_level != NULL)
                *p_txqueue_level = params.rate_limit.queue_level;
        return (error);
}

/*
 * Allocate a new TX rate limit send tag from the network interface
 * given by the "ifp" argument and save it in "inp->inp_snd_tag":
 */
int
in_pcbattach_txrtlmt(struct inpcb *inp, struct ifnet *ifp,
    uint32_t flowtype, uint32_t flowid, uint32_t max_pacing_rate, struct m_snd_tag **st)

{
        union if_snd_tag_alloc_params params = {
                .rate_limit.hdr.type = (max_pacing_rate == -1U) ?
                    IF_SND_TAG_TYPE_UNLIMITED : IF_SND_TAG_TYPE_RATE_LIMIT,
                .rate_limit.hdr.flowid = flowid,
                .rate_limit.hdr.flowtype = flowtype,
                .rate_limit.hdr.numa_domain = inp->inp_numa_domain,
                .rate_limit.max_rate = max_pacing_rate,
                .rate_limit.flags = M_NOWAIT,
        };
        int error;

        INP_WLOCK_ASSERT(inp);

        /*
         * If there is already a send tag, or the INP is being torn
         * down, allocating a new send tag is not allowed. Else send
         * tags may leak.
         */
        if (*st != NULL || (inp->inp_flags & INP_DROPPED) != 0)
                return (EINVAL);

        error = m_snd_tag_alloc(ifp, &params, st);
#ifdef INET
        if (error == 0) {
                counter_u64_add(rate_limit_set_ok, 1);
                counter_u64_add(rate_limit_active, 1);
        } else if (error != EOPNOTSUPP)
                  counter_u64_add(rate_limit_alloc_fail, 1);
#endif
        return (error);
}

void
in_pcbdetach_tag(struct m_snd_tag *mst)
{

        m_snd_tag_rele(mst);
#ifdef INET
        counter_u64_add(rate_limit_active, -1);
#endif
}

/*
 * Free an existing TX rate limit tag based on the "inp->inp_snd_tag",
 * if any:
 */
void
in_pcbdetach_txrtlmt(struct inpcb *inp)
{
        struct m_snd_tag *mst;

        INP_WLOCK_ASSERT(inp);

        mst = inp->inp_snd_tag;
        inp->inp_snd_tag = NULL;

        if (mst == NULL)
                return;

        m_snd_tag_rele(mst);
#ifdef INET
        counter_u64_add(rate_limit_active, -1);
#endif
}

int
in_pcboutput_txrtlmt_locked(struct inpcb *inp, struct ifnet *ifp, struct mbuf *mb, uint32_t max_pacing_rate)
{
        int error;

        /*
         * If the existing send tag is for the wrong interface due to
         * a route change, first drop the existing tag.  Set the
         * CHANGED flag so that we will keep trying to allocate a new
         * tag if we fail to allocate one this time.
         */
        if (inp->inp_snd_tag != NULL && inp->inp_snd_tag->ifp != ifp) {
                in_pcbdetach_txrtlmt(inp);
                inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
        }

        /*
         * NOTE: When attaching to a network interface a reference is
         * made to ensure the network interface doesn't go away until
         * all ratelimit connections are gone. The network interface
         * pointers compared below represent valid network interfaces,
         * except when comparing towards NULL.
         */
        if (max_pacing_rate == 0 && inp->inp_snd_tag == NULL) {
                error = 0;
        } else if (!(ifp->if_capenable & IFCAP_TXRTLMT)) {
                if (inp->inp_snd_tag != NULL)
                        in_pcbdetach_txrtlmt(inp);
                error = 0;
        } else if (inp->inp_snd_tag == NULL) {
                /*
                 * In order to utilize packet pacing with RSS, we need
                 * to wait until there is a valid RSS hash before we
                 * can proceed:
                 */
                if (M_HASHTYPE_GET(mb) == M_HASHTYPE_NONE) {
                        error = EAGAIN;
                } else {
                        error = in_pcbattach_txrtlmt(inp, ifp, M_HASHTYPE_GET(mb),
                            mb->m_pkthdr.flowid, max_pacing_rate, &inp->inp_snd_tag);
                }
        } else {
                error = in_pcbmodify_txrtlmt(inp, max_pacing_rate);
        }
        if (error == 0 || error == EOPNOTSUPP)
                inp->inp_flags2 &= ~INP_RATE_LIMIT_CHANGED;

        return (error);
}

/*
 * This function should be called when the INP_RATE_LIMIT_CHANGED flag
 * is set in the fast path and will attach/detach/modify the TX rate
 * limit send tag based on the socket's so_max_pacing_rate value.
 */
void
in_pcboutput_txrtlmt(struct inpcb *inp, struct ifnet *ifp, struct mbuf *mb)
{
        struct socket *socket;
        uint32_t max_pacing_rate;
        bool did_upgrade;

        if (inp == NULL)
                return;

        socket = inp->inp_socket;
        if (socket == NULL)
                return;

        if (!INP_WLOCKED(inp)) {
                /*
                 * NOTE: If the write locking fails, we need to bail
                 * out and use the non-ratelimited ring for the
                 * transmit until there is a new chance to get the
                 * write lock.
                 */
                if (!INP_TRY_UPGRADE(inp))
                        return;
                did_upgrade = 1;
        } else {
                did_upgrade = 0;
        }

        /*
         * NOTE: The so_max_pacing_rate value is read unlocked,
         * because atomic updates are not required since the variable
         * is checked at every mbuf we send. It is assumed that the
         * variable read itself will be atomic.
         */
        max_pacing_rate = socket->so_max_pacing_rate;

        in_pcboutput_txrtlmt_locked(inp, ifp, mb, max_pacing_rate);

        if (did_upgrade)
                INP_DOWNGRADE(inp);
}

/*
 * Track route changes for TX rate limiting.
 */
void
in_pcboutput_eagain(struct inpcb *inp)
{
        bool did_upgrade;

        if (inp == NULL)
                return;

        if (inp->inp_snd_tag == NULL)
                return;

        if (!INP_WLOCKED(inp)) {
                /*
                 * NOTE: If the write locking fails, we need to bail
                 * out and use the non-ratelimited ring for the
                 * transmit until there is a new chance to get the
                 * write lock.
                 */
                if (!INP_TRY_UPGRADE(inp))
                        return;
                did_upgrade = 1;
        } else {
                did_upgrade = 0;
        }

        /* detach rate limiting */
        in_pcbdetach_txrtlmt(inp);

        /* make sure new mbuf send tag allocation is made */
        inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;

        if (did_upgrade)
                INP_DOWNGRADE(inp);
}

#ifdef INET
static void
rl_init(void *st)
{
        rate_limit_new = counter_u64_alloc(M_WAITOK);
        rate_limit_chg = counter_u64_alloc(M_WAITOK);
        rate_limit_active = counter_u64_alloc(M_WAITOK);
        rate_limit_alloc_fail = counter_u64_alloc(M_WAITOK);
        rate_limit_set_ok = counter_u64_alloc(M_WAITOK);
}

SYSINIT(rl, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, rl_init, NULL);
#endif
#endif /* RATELIMIT */