/src/SockFuzzer/third_party/xnu/bsd/netinet6/in6.c

Source
/*
 * Copyright (c) 2003-2020 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 *
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 *
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 *
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */

/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * All rights reserved.
 *
 * 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 project 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 PROJECT 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 PROJECT 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.
 */

/*
 * Copyright (c) 1982, 1986, 1991, 1993
 *  The Regents of the University of California.  All rights reserved.
 *
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *  This product includes software developed by the University of
 *  California, Berkeley and its contributors.
 * 4. 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.
 *
 *  @(#)in.c  8.2 (Berkeley) 11/15/93
 */


#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/errno.h>
#include <sys/malloc.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sockio.h>
#include <sys/systm.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#include <sys/kern_event.h>
#include <sys/mcache.h>
#include <sys/protosw.h>
#include <sys/sysctl.h>

#include <kern/locks.h>
#include <kern/zalloc.h>
#include <kern/clock.h>
#include <libkern/OSAtomic.h>
#include <machine/machine_routines.h>
#include <mach/boolean.h>

#include <net/if.h>
#include <net/if_types.h>
#include <net/if_var.h>
#include <net/route.h>
#include <net/if_dl.h>
#include <net/kpi_protocol.h>
#include <net/nwk_wq.h>

#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/if_ether.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/in_pcb.h>
#include <netinet/icmp6.h>
#include <netinet/tcp.h>
#include <netinet/tcp_seq.h>
#include <netinet/tcp_var.h>

#include <netinet6/nd6.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/mld6_var.h>
#include <netinet6/in6_ifattach.h>
#include <netinet6/scope6_var.h>
#include <netinet6/in6_var.h>
#include <netinet6/in6_pcb.h>

#include <net/net_osdep.h>

#include <net/dlil.h>
#include <net/if_llatbl.h>

#if PF
#include <net/pfvar.h>
#endif /* PF */

/*
 * Definitions of some costant IP6 addresses.
 */
const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
const struct in6_addr in6addr_nodelocal_allnodes =
    IN6ADDR_NODELOCAL_ALLNODES_INIT;
const struct in6_addr in6addr_linklocal_allnodes =
    IN6ADDR_LINKLOCAL_ALLNODES_INIT;
const struct in6_addr in6addr_linklocal_allrouters =
    IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
const struct in6_addr in6addr_linklocal_allv2routers =
    IN6ADDR_LINKLOCAL_ALLV2ROUTERS_INIT;
const struct in6_addr in6addr_multicast_prefix =
    IN6ADDR_MULTICAST_PREFIX;

const struct in6_addr in6mask0 = IN6MASK0;
const struct in6_addr in6mask7 = IN6MASK7;
const struct in6_addr in6mask8 = IN6MASK8;
const struct in6_addr in6mask16 = IN6MASK16;
const struct in6_addr in6mask32 = IN6MASK32;
const struct in6_addr in6mask64 = IN6MASK64;
const struct in6_addr in6mask96 = IN6MASK96;
const struct in6_addr in6mask128 = IN6MASK128;

const struct sockaddr_in6 sa6_any = {
  .sin6_len = sizeof(sa6_any),
  .sin6_family = AF_INET6,
  .sin6_port = 0,
  .sin6_flowinfo = 0,
  .sin6_addr = IN6ADDR_ANY_INIT,
  .sin6_scope_id = 0
};

static int in6ctl_associd(struct socket *, u_long, caddr_t);
static int in6ctl_connid(struct socket *, u_long, caddr_t);
static int in6ctl_conninfo(struct socket *, u_long, caddr_t);
static int in6ctl_llstart(struct ifnet *, u_long, caddr_t);
static int in6ctl_llstop(struct ifnet *);
static int in6ctl_cgastart(struct ifnet *, u_long, caddr_t);
static int in6ctl_gifaddr(struct ifnet *, struct in6_ifaddr *, u_long,
    struct in6_ifreq *);
static int in6ctl_gifstat(struct ifnet *, u_long, struct in6_ifreq *);
static int in6ctl_alifetime(struct in6_ifaddr *, u_long, struct in6_ifreq *,
    boolean_t);
static int in6ctl_aifaddr(struct ifnet *, struct in6_aliasreq *);
static void in6ctl_difaddr(struct ifnet *, struct in6_ifaddr *);
static int in6_autoconf(struct ifnet *, int);
static int in6_setrouter(struct ifnet *, ipv6_router_mode_t);
static int in6_ifinit(struct ifnet *, struct in6_ifaddr *, int);
static int in6_ifaupdate_aux(struct in6_ifaddr *, struct ifnet *, int);
static void in6_unlink_ifa(struct in6_ifaddr *, struct ifnet *);
static struct in6_ifaddr *in6_ifaddr_alloc(zalloc_flags_t);
static void in6_ifaddr_attached(struct ifaddr *);
static void in6_ifaddr_detached(struct ifaddr *);
static void in6_ifaddr_free(struct ifaddr *);
static void in6_ifaddr_trace(struct ifaddr *, int);
#if defined(__LP64__)
static void in6_cgareq_32_to_64(const struct in6_cgareq_32 *,
    struct in6_cgareq_64 *);
#else
static void in6_cgareq_64_to_32(const struct in6_cgareq_64 *,
    struct in6_cgareq_32 *);
#endif
static struct in6_aliasreq *in6_aliasreq_to_native(void *, int,
    struct in6_aliasreq *);
static int in6_to_kamescope(struct sockaddr_in6 *, struct ifnet *);
static int in6_getassocids(struct socket *, uint32_t *, user_addr_t);
static int in6_getconnids(struct socket *, sae_associd_t, uint32_t *,
    user_addr_t);

static void in6_if_up_dad_start(struct ifnet *);

#define IA6_HASH_INIT(ia) {                                      \
  (ia)->ia6_hash.tqe_next = (void *)(uintptr_t)-1;         \
  (ia)->ia6_hash.tqe_prev = (void *)(uintptr_t)-1;         \
}

#define IA6_IS_HASHED(ia)                                        \
  (!((ia)->ia6_hash.tqe_next == (void *)(uintptr_t)-1 ||   \
  (ia)->ia6_hash.tqe_prev == (void *)(uintptr_t)-1))

static void in6_iahash_remove(struct in6_ifaddr *);
static void in6_iahash_insert(struct in6_ifaddr *);
static void in6_iahash_insert_ptp(struct in6_ifaddr *);

extern lck_mtx_t *nd6_mutex;

#define IN6IFA_TRACE_HIST_SIZE  32      /* size of trace history */

/* For gdb */
__private_extern__ unsigned int in6ifa_trace_hist_size = IN6IFA_TRACE_HIST_SIZE;

struct in6_ifaddr_dbg {
  struct in6_ifaddr       in6ifa;                 /* in6_ifaddr */
  struct in6_ifaddr       in6ifa_old;             /* saved in6_ifaddr */
  u_int16_t               in6ifa_refhold_cnt;     /* # of IFA_ADDREF */
  u_int16_t               in6ifa_refrele_cnt;     /* # of IFA_REMREF */
  /*
   * Alloc and free callers.
   */
  ctrace_t                in6ifa_alloc;
  ctrace_t                in6ifa_free;
  /*
   * Circular lists of IFA_ADDREF and IFA_REMREF callers.
   */
  ctrace_t                in6ifa_refhold[IN6IFA_TRACE_HIST_SIZE];
  ctrace_t                in6ifa_refrele[IN6IFA_TRACE_HIST_SIZE];
  /*
   * Trash list linkage
   */
  TAILQ_ENTRY(in6_ifaddr_dbg) in6ifa_trash_link;
};

/* List of trash in6_ifaddr entries protected by in6ifa_trash_lock */
static TAILQ_HEAD(, in6_ifaddr_dbg) in6ifa_trash_head;
static decl_lck_mtx_data(, in6ifa_trash_lock);

#if DEBUG
static unsigned int in6ifa_debug = 1;           /* debugging (enabled) */
#else
static unsigned int in6ifa_debug;               /* debugging (disabled) */
#endif /* !DEBUG */
static struct zone *in6ifa_zone;                /* zone for in6_ifaddr */
#define IN6IFA_ZONE_NAME        "in6_ifaddr"    /* zone name */

struct eventhandler_lists_ctxt in6_evhdlr_ctxt;
struct eventhandler_lists_ctxt in6_clat46_evhdlr_ctxt;
/*
 * Subroutine for in6_ifaddloop() and in6_ifremloop().
 * This routine does actual work.
 */
static void
in6_ifloop_request(int cmd, struct ifaddr *ifa)
{
  struct sockaddr_in6 all1_sa;
  struct rtentry *nrt = NULL;
  int e;

  bzero(&all1_sa, sizeof(all1_sa));
  all1_sa.sin6_family = AF_INET6;
  all1_sa.sin6_len = sizeof(struct sockaddr_in6);
  all1_sa.sin6_addr = in6mask128;

  /*
   * We specify the address itself as the gateway, and set the
   * RTF_LLINFO flag, so that the corresponding host route would have
   * the flag, and thus applications that assume traditional behavior
   * would be happy.  Note that we assume the caller of the function
   * (probably implicitly) set nd6_rtrequest() to ifa->ifa_rtrequest,
   * which changes the outgoing interface to the loopback interface.
   * ifa_addr for INET6 is set once during init; no need to hold lock.
   */
  lck_mtx_lock(rnh_lock);
  e = rtrequest_locked(cmd, ifa->ifa_addr, ifa->ifa_addr,
      (struct sockaddr *)&all1_sa, RTF_UP | RTF_HOST | RTF_LLINFO, &nrt);
  if (e != 0) {
    log(LOG_ERR, "in6_ifloop_request: "
        "%s operation failed for %s (errno=%d)\n",
        cmd == RTM_ADD ? "ADD" : "DELETE",
        ip6_sprintf(&((struct in6_ifaddr *)ifa)->ia_addr.sin6_addr),
        e);
  }

  if (nrt != NULL) {
    RT_LOCK(nrt);
  }
  /*
   * Make sure rt_ifa be equal to IFA, the second argument of the
   * function.
   * We need this because when we refer to rt_ifa->ia6_flags in
   * ip6_input, we assume that the rt_ifa points to the address instead
   * of the loopback address.
   */
  if (cmd == RTM_ADD && nrt && ifa != nrt->rt_ifa) {
    rtsetifa(nrt, ifa);
  }

  /*
   * Report the addition/removal of the address to the routing socket.
   * XXX: since we called rtinit for a p2p interface with a destination,
   *   we end up reporting twice in such a case.  Should we rather
   *   omit the second report?
   */
  if (nrt != NULL) {
    rt_newaddrmsg(cmd, ifa, e, nrt);
    if (cmd == RTM_DELETE) {
      RT_UNLOCK(nrt);
      rtfree_locked(nrt);
    } else {
      /* the cmd must be RTM_ADD here */
      RT_REMREF_LOCKED(nrt);
      RT_UNLOCK(nrt);
    }
  }
  lck_mtx_unlock(rnh_lock);
}

/*
 * Add ownaddr as loopback rtentry.  We previously add the route only if
 * necessary (ex. on a p2p link).  However, since we now manage addresses
 * separately from prefixes, we should always add the route.  We can't
 * rely on the cloning mechanism from the corresponding interface route
 * any more.
 */
static void
in6_ifaddloop(struct ifaddr *ifa)
{
  struct rtentry *rt;

  /*
   * If there is no loopback entry, allocate one.  ifa_addr for
   * INET6 is set once during init; no need to hold lock.
   */
  rt = rtalloc1(ifa->ifa_addr, 0, 0);
  if (rt != NULL) {
    RT_LOCK(rt);
  }
  if (rt == NULL || (rt->rt_flags & RTF_HOST) == 0 ||
      (rt->rt_ifp->if_flags & IFF_LOOPBACK) == 0) {
    if (rt != NULL) {
      RT_REMREF_LOCKED(rt);
      RT_UNLOCK(rt);
    }
    in6_ifloop_request(RTM_ADD, ifa);
  } else if (rt != NULL) {
    RT_REMREF_LOCKED(rt);
    RT_UNLOCK(rt);
  }
}

/*
 * Remove loopback rtentry of ownaddr generated by in6_ifaddloop(),
 * if it exists.
 */
static void
in6_ifremloop(struct ifaddr *ifa)
{
  struct in6_ifaddr *ia;
  struct rtentry *rt;
  int ia_count = 0;

  /*
   * Some of BSD variants do not remove cloned routes
   * from an interface direct route, when removing the direct route
   * (see comments in net/net_osdep.h).  Even for variants that do remove
   * cloned routes, they could fail to remove the cloned routes when
   * we handle multple addresses that share a common prefix.
   * So, we should remove the route corresponding to the deleted address
   * regardless of the result of in6_is_ifloop_auto().
   */

  /*
   * Delete the entry only if exact one ifa exists.  More than one ifa
   * can exist if we assign a same single address to multiple
   * (probably p2p) interfaces.
   * XXX: we should avoid such a configuration in IPv6...
   */
  lck_rw_lock_exclusive(&in6_ifaddr_rwlock);
  TAILQ_FOREACH(ia, IN6ADDR_HASH(IFA_IN6(ifa)), ia6_hash) {
    IFA_LOCK(&ia->ia_ifa);
    if (IN6_ARE_ADDR_EQUAL(IFA_IN6(ifa), &ia->ia_addr.sin6_addr)) {
      ia_count++;
      if (ia_count > 1) {
        IFA_UNLOCK(&ia->ia_ifa);
        break;
      }
    }
    IFA_UNLOCK(&ia->ia_ifa);
  }
  lck_rw_done(&in6_ifaddr_rwlock);

  if (ia_count == 1) {
    /*
     * Before deleting, check if a corresponding loopbacked host
     * route surely exists.  With this check, we can avoid to
     * delete an interface direct route whose destination is same
     * as the address being removed.  This can happen when removing
     * a subnet-router anycast address on an interface attahced
     * to a shared medium.  ifa_addr for INET6 is set once during
     * init; no need to hold lock.
     */
    rt = rtalloc1(ifa->ifa_addr, 0, 0);
    if (rt != NULL) {
      RT_LOCK(rt);
      if ((rt->rt_flags & RTF_HOST) != 0 &&
          (rt->rt_ifp->if_flags & IFF_LOOPBACK) != 0) {
        RT_REMREF_LOCKED(rt);
        RT_UNLOCK(rt);
        in6_ifloop_request(RTM_DELETE, ifa);
      } else {
        RT_UNLOCK(rt);
      }
    }
  }
}


int
in6_mask2len(struct in6_addr *mask, u_char *lim0)
{
  int x = 0, y;
  u_char *lim = lim0, *p;

  /* ignore the scope_id part */
  if (lim0 == NULL || lim0 - (u_char *)mask > sizeof(*mask)) {
    lim = (u_char *)mask + sizeof(*mask);
  }
  for (p = (u_char *)mask; p < lim; x++, p++) {
    if (*p != 0xff) {
      break;
    }
  }
  y = 0;
  if (p < lim) {
    for (y = 0; y < 8; y++) {
      if ((*p & (0x80 >> y)) == 0) {
        break;
      }
    }
  }

  /*
   * when the limit pointer is given, do a stricter check on the
   * remaining bits.
   */
  if (p < lim) {
    if (y != 0 && (*p & (0x00ff >> y)) != 0) {
      return -1;
    }
    for (p = p + 1; p < lim; p++) {
      if (*p != 0) {
        return -1;
      }
    }
  }

  return x * 8 + y;
}

void
in6_len2mask(struct in6_addr *mask, int len)
{
  int i;

  bzero(mask, sizeof(*mask));
  for (i = 0; i < len / 8; i++) {
    mask->s6_addr8[i] = 0xff;
  }
  if (len % 8) {
    mask->s6_addr8[i] = (0xff00 >> (len % 8)) & 0xff;
  }
}

void
in6_aliasreq_64_to_32(struct in6_aliasreq_64 *src, struct in6_aliasreq_32 *dst)
{
  bzero(dst, sizeof(*dst));
  bcopy(src->ifra_name, dst->ifra_name, sizeof(dst->ifra_name));
  dst->ifra_addr = src->ifra_addr;
  dst->ifra_dstaddr = src->ifra_dstaddr;
  dst->ifra_prefixmask = src->ifra_prefixmask;
  dst->ifra_flags = src->ifra_flags;
  dst->ifra_lifetime.ia6t_expire = (u_int32_t)src->ifra_lifetime.ia6t_expire;
  dst->ifra_lifetime.ia6t_preferred = (u_int32_t)src->ifra_lifetime.ia6t_preferred;
  dst->ifra_lifetime.ia6t_vltime = src->ifra_lifetime.ia6t_vltime;
  dst->ifra_lifetime.ia6t_pltime = src->ifra_lifetime.ia6t_pltime;
}

void
in6_aliasreq_32_to_64(struct in6_aliasreq_32 *src, struct in6_aliasreq_64 *dst)
{
  bzero(dst, sizeof(*dst));
  bcopy(src->ifra_name, dst->ifra_name, sizeof(dst->ifra_name));
  dst->ifra_addr = src->ifra_addr;
  dst->ifra_dstaddr = src->ifra_dstaddr;
  dst->ifra_prefixmask = src->ifra_prefixmask;
  dst->ifra_flags = src->ifra_flags;
  dst->ifra_lifetime.ia6t_expire = src->ifra_lifetime.ia6t_expire;
  dst->ifra_lifetime.ia6t_preferred = src->ifra_lifetime.ia6t_preferred;
  dst->ifra_lifetime.ia6t_vltime = src->ifra_lifetime.ia6t_vltime;
  dst->ifra_lifetime.ia6t_pltime = src->ifra_lifetime.ia6t_pltime;
}

#if defined(__LP64__)
static void
in6_cgareq_32_to_64(const struct in6_cgareq_32 *src,
    struct in6_cgareq_64 *dst)
{
  bzero(dst, sizeof(*dst));
  bcopy(src->cgar_name, dst->cgar_name, sizeof(dst->cgar_name));
  dst->cgar_flags = src->cgar_flags;
  bcopy(src->cgar_cgaprep.cga_modifier.octets,
      dst->cgar_cgaprep.cga_modifier.octets,
      sizeof(dst->cgar_cgaprep.cga_modifier.octets));
  dst->cgar_cgaprep.cga_security_level =
      src->cgar_cgaprep.cga_security_level;
  dst->cgar_lifetime.ia6t_expire = src->cgar_lifetime.ia6t_expire;
  dst->cgar_lifetime.ia6t_preferred = src->cgar_lifetime.ia6t_preferred;
  dst->cgar_lifetime.ia6t_vltime = src->cgar_lifetime.ia6t_vltime;
  dst->cgar_lifetime.ia6t_pltime = src->cgar_lifetime.ia6t_pltime;
  dst->cgar_collision_count = src->cgar_collision_count;
}
#endif

#if !defined(__LP64__)
static void
in6_cgareq_64_to_32(const struct in6_cgareq_64 *src,
    struct in6_cgareq_32 *dst)
{
  bzero(dst, sizeof(*dst));
  bcopy(src->cgar_name, dst->cgar_name, sizeof(dst->cgar_name));
  dst->cgar_flags = src->cgar_flags;
  bcopy(src->cgar_cgaprep.cga_modifier.octets,
      dst->cgar_cgaprep.cga_modifier.octets,
      sizeof(dst->cgar_cgaprep.cga_modifier.octets));
  dst->cgar_cgaprep.cga_security_level =
      src->cgar_cgaprep.cga_security_level;
  dst->cgar_lifetime.ia6t_expire = src->cgar_lifetime.ia6t_expire;
  dst->cgar_lifetime.ia6t_preferred = src->cgar_lifetime.ia6t_preferred;
  dst->cgar_lifetime.ia6t_vltime = src->cgar_lifetime.ia6t_vltime;
  dst->cgar_lifetime.ia6t_pltime = src->cgar_lifetime.ia6t_pltime;
  dst->cgar_collision_count = src->cgar_collision_count;
}
#endif

static struct in6_aliasreq *
in6_aliasreq_to_native(void *data, int data_is_64, struct in6_aliasreq *dst)
{
#if defined(__LP64__)
  if (data_is_64) {
    bcopy(data, dst, sizeof(*dst));
  } else {
    in6_aliasreq_32_to_64((struct in6_aliasreq_32 *)data,
        (struct in6_aliasreq_64 *)dst);
  }
#else
  if (data_is_64) {
    in6_aliasreq_64_to_32((struct in6_aliasreq_64 *)data,
        (struct in6_aliasreq_32 *)dst);
  } else {
    bcopy(data, dst, sizeof(*dst));
  }
#endif /* __LP64__ */
  return dst;
}

void
in6_cgareq_copy_from_user(const void *user_data, int user_is_64,
    struct in6_cgareq *cgareq)
{
#if defined(__LP64__)
  if (user_is_64) {
    bcopy(user_data, cgareq, sizeof(*cgareq));
  } else {
    in6_cgareq_32_to_64((const struct in6_cgareq_32 *)user_data,
        (struct in6_cgareq_64 *)cgareq);
  }
#else
  if (user_is_64) {
    in6_cgareq_64_to_32((const struct in6_cgareq_64 *)user_data,
        (struct in6_cgareq_32 *)cgareq);
  } else {
    bcopy(user_data, cgareq, sizeof(*cgareq));
  }
#endif /* __LP64__ */
}

static __attribute__((noinline)) int
in6ctl_associd(struct socket *so, u_long cmd, caddr_t data)
{
  int error = 0;
  union {
    struct so_aidreq32 a32;
    struct so_aidreq64 a64;
  } u;

  VERIFY(so != NULL);

  switch (cmd) {
  case SIOCGASSOCIDS32: {         /* struct so_aidreq32 */
    bcopy(data, &u.a32, sizeof(u.a32));
    error = in6_getassocids(so, &u.a32.sar_cnt, u.a32.sar_aidp);
    if (error == 0) {
      bcopy(&u.a32, data, sizeof(u.a32));
    }
    break;
  }

  case SIOCGASSOCIDS64: {         /* struct so_aidreq64 */
    bcopy(data, &u.a64, sizeof(u.a64));
    error = in6_getassocids(so, &u.a64.sar_cnt, u.a64.sar_aidp);
    if (error == 0) {
      bcopy(&u.a64, data, sizeof(u.a64));
    }
    break;
  }

  default:
    VERIFY(0);
    /* NOTREACHED */
  }

  return error;
}

static __attribute__((noinline)) int
in6ctl_connid(struct socket *so, u_long cmd, caddr_t data)
{
  int error = 0;
  union {
    struct so_cidreq32 c32;
    struct so_cidreq64 c64;
  } u;

  VERIFY(so != NULL);

  switch (cmd) {
  case SIOCGCONNIDS32: {          /* struct so_cidreq32 */
    bcopy(data, &u.c32, sizeof(u.c32));
    error = in6_getconnids(so, u.c32.scr_aid, &u.c32.scr_cnt,
        u.c32.scr_cidp);
    if (error == 0) {
      bcopy(&u.c32, data, sizeof(u.c32));
    }
    break;
  }

  case SIOCGCONNIDS64: {          /* struct so_cidreq64 */
    bcopy(data, &u.c64, sizeof(u.c64));
    error = in6_getconnids(so, u.c64.scr_aid, &u.c64.scr_cnt,
        u.c64.scr_cidp);
    if (error == 0) {
      bcopy(&u.c64, data, sizeof(u.c64));
    }
    break;
  }

  default:
    VERIFY(0);
    /* NOTREACHED */
  }

  return error;
}

static __attribute__((noinline)) int
in6ctl_conninfo(struct socket *so, u_long cmd, caddr_t data)
{
  int error = 0;
  union {
    struct so_cinforeq32 ci32;
    struct so_cinforeq64 ci64;
  } u;

  VERIFY(so != NULL);

  switch (cmd) {
  case SIOCGCONNINFO32: {         /* struct so_cinforeq32 */
    bcopy(data, &u.ci32, sizeof(u.ci32));
    error = in6_getconninfo(so, u.ci32.scir_cid, &u.ci32.scir_flags,
        &u.ci32.scir_ifindex, &u.ci32.scir_error, u.ci32.scir_src,
        &u.ci32.scir_src_len, u.ci32.scir_dst, &u.ci32.scir_dst_len,
        &u.ci32.scir_aux_type, u.ci32.scir_aux_data,
        &u.ci32.scir_aux_len);
    if (error == 0) {
      bcopy(&u.ci32, data, sizeof(u.ci32));
    }
    break;
  }

  case SIOCGCONNINFO64: {         /* struct so_cinforeq64 */
    bcopy(data, &u.ci64, sizeof(u.ci64));
    error = in6_getconninfo(so, u.ci64.scir_cid, &u.ci64.scir_flags,
        &u.ci64.scir_ifindex, &u.ci64.scir_error, u.ci64.scir_src,
        &u.ci64.scir_src_len, u.ci64.scir_dst, &u.ci64.scir_dst_len,
        &u.ci64.scir_aux_type, u.ci64.scir_aux_data,
        &u.ci64.scir_aux_len);
    if (error == 0) {
      bcopy(&u.ci64, data, sizeof(u.ci64));
    }
    break;
  }

  default:
    VERIFY(0);
    /* NOTREACHED */
  }

  return error;
}

static __attribute__((noinline)) int
in6ctl_llstart(struct ifnet *ifp, u_long cmd, caddr_t data)
{
  struct in6_aliasreq sifra, *ifra = NULL;
  boolean_t is64;
  int error = 0;

  VERIFY(ifp != NULL);

  switch (cmd) {
  case SIOCLL_START_32:           /* struct in6_aliasreq_32 */
  case SIOCLL_START_64:           /* struct in6_aliasreq_64 */
    is64 = (cmd == SIOCLL_START_64);
    /*
     * Convert user ifra to the kernel form, when appropriate.
     * This allows the conversion between different data models
     * to be centralized, so that it can be passed around to other
     * routines that are expecting the kernel form.
     */
    ifra = in6_aliasreq_to_native(data, is64, &sifra);

    /*
     * NOTE: All the interface specific DLIL attachements should
     * be done here.  They are currently done in in6_ifattach_aux()
     * for the interfaces that need it.
     */
    if (ifra->ifra_addr.sin6_family == AF_INET6 &&
        /* Only check ifra_dstaddr if valid */
        (ifra->ifra_dstaddr.sin6_len == 0 ||
        ifra->ifra_dstaddr.sin6_family == AF_INET6)) {
      /* some interfaces may provide LinkLocal addresses */
      error = in6_ifattach_aliasreq(ifp, NULL, ifra);
    } else {
      error = in6_ifattach_aliasreq(ifp, NULL, NULL);
    }
    if (error == 0) {
      in6_if_up_dad_start(ifp);
    }
    break;

  default:
    VERIFY(0);
    /* NOTREACHED */
  }

  return error;
}

static __attribute__((noinline)) int
in6ctl_llstop(struct ifnet *ifp)
{
  struct in6_ifaddr *ia;
  struct nd_prefix pr0, *pr;

  VERIFY(ifp != NULL);

  /* Remove link local addresses from interface */
  lck_rw_lock_exclusive(&in6_ifaddr_rwlock);
  boolean_t from_begining = TRUE;
  while (from_begining) {
    from_begining = FALSE;
    TAILQ_FOREACH(ia, &in6_ifaddrhead, ia6_link) {
      if (ia->ia_ifa.ifa_ifp != ifp) {
        continue;
      }
      IFA_LOCK(&ia->ia_ifa);
      if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) {
        IFA_ADDREF_LOCKED(&ia->ia_ifa); /* for us */
        IFA_UNLOCK(&ia->ia_ifa);
        lck_rw_done(&in6_ifaddr_rwlock);
        in6_purgeaddr(&ia->ia_ifa);
        IFA_REMREF(&ia->ia_ifa);        /* for us */
        lck_rw_lock_exclusive(&in6_ifaddr_rwlock);
        /*
         * Purging the address caused in6_ifaddr_rwlock
         * to be dropped and reacquired;
         * therefore search again from the beginning
         * of in6_ifaddrs list.
         */
        from_begining = TRUE;
        break;
      }
      IFA_UNLOCK(&ia->ia_ifa);
    }
  }
  lck_rw_done(&in6_ifaddr_rwlock);

  /* Delete the link local prefix */
  bzero(&pr0, sizeof(pr0));
  pr0.ndpr_plen = 64;
  pr0.ndpr_ifp = ifp;
  pr0.ndpr_prefix.sin6_addr.s6_addr16[0] = IPV6_ADDR_INT16_ULL;
  (void)in6_setscope(&pr0.ndpr_prefix.sin6_addr, ifp, NULL);
  pr = nd6_prefix_lookup(&pr0, ND6_PREFIX_EXPIRY_UNSPEC);
  if (pr) {
    lck_mtx_lock(nd6_mutex);
    NDPR_LOCK(pr);
    prelist_remove(pr);
    NDPR_UNLOCK(pr);
    NDPR_REMREF(pr); /* Drop the reference from lookup */
    lck_mtx_unlock(nd6_mutex);
  }

  return 0;
}

/*
 * This routine configures secure link local address
 */
static __attribute__((noinline)) int
in6ctl_cgastart(struct ifnet *ifp, u_long cmd, caddr_t data)
{
  struct in6_cgareq llcgasr;
  int is64, error = 0;

  VERIFY(ifp != NULL);

  switch (cmd) {
  case SIOCLL_CGASTART_32:        /* struct in6_cgareq_32 */
  case SIOCLL_CGASTART_64:        /* struct in6_cgareq_64 */
    is64 = (cmd == SIOCLL_CGASTART_64);
    /*
     * Convert user cgareq to the kernel form, when appropriate.
     * This allows the conversion between different data models
     * to be centralized, so that it can be passed around to other
     * routines that are expecting the kernel form.
     */
    in6_cgareq_copy_from_user(data, is64, &llcgasr);

    /*
     * NOTE: All the interface specific DLIL attachements
     * should be done here.  They are currently done in
     * in6_ifattach_cgareq() for the interfaces that
     * need it.
     */
    error = in6_ifattach_llcgareq(ifp, &llcgasr);
    if (error == 0) {
      in6_if_up_dad_start(ifp);
    }
    break;

  default:
    VERIFY(0);
    /* NOTREACHED */
  }

  return error;
}

/*
 * Caller passes in the ioctl data pointer directly via "ifr", with the
 * expectation that this routine always uses bcopy() or other byte-aligned
 * memory accesses.
 */
static __attribute__((noinline)) int
in6ctl_gifaddr(struct ifnet *ifp, struct in6_ifaddr *ia, u_long cmd,
    struct in6_ifreq *ifr)
{
  struct sockaddr_in6 addr;
  int error = 0;

  VERIFY(ifp != NULL);

  if (ia == NULL) {
    return EADDRNOTAVAIL;
  }

  switch (cmd) {
  case SIOCGIFADDR_IN6:           /* struct in6_ifreq */
    IFA_LOCK(&ia->ia_ifa);
    bcopy(&ia->ia_addr, &addr, sizeof(addr));
    IFA_UNLOCK(&ia->ia_ifa);
    if ((error = sa6_recoverscope(&addr, TRUE)) != 0) {
      break;
    }
    bcopy(&addr, &ifr->ifr_addr, sizeof(addr));
    break;

  case SIOCGIFDSTADDR_IN6:        /* struct in6_ifreq */
    if (!(ifp->if_flags & IFF_POINTOPOINT)) {
      error = EINVAL;
      break;
    }
    /*
     * XXX: should we check if ifa_dstaddr is NULL and return
     * an error?
     */
    IFA_LOCK(&ia->ia_ifa);
    bcopy(&ia->ia_dstaddr, &addr, sizeof(addr));
    IFA_UNLOCK(&ia->ia_ifa);
    if ((error = sa6_recoverscope(&addr, TRUE)) != 0) {
      break;
    }
    bcopy(&addr, &ifr->ifr_dstaddr, sizeof(addr));
    break;

  default:
    VERIFY(0);
    /* NOTREACHED */
  }

  return error;
}

/*
 * Caller passes in the ioctl data pointer directly via "ifr", with the
 * expectation that this routine always uses bcopy() or other byte-aligned
 * memory accesses.
 */
static __attribute__((noinline)) int
in6ctl_gifstat(struct ifnet *ifp, u_long cmd, struct in6_ifreq *ifr)
{
  int error = 0, index;

  VERIFY(ifp != NULL);
  index = ifp->if_index;

  switch (cmd) {
  case SIOCGIFSTAT_IN6:           /* struct in6_ifreq */
    /* N.B.: if_inet6data is never freed once set. */
    if (IN6_IFEXTRA(ifp) == NULL) {
      /* return (EAFNOSUPPORT)? */
      bzero(&ifr->ifr_ifru.ifru_stat,
          sizeof(ifr->ifr_ifru.ifru_stat));
    } else {
      bcopy(&IN6_IFEXTRA(ifp)->in6_ifstat,
          &ifr->ifr_ifru.ifru_stat,
          sizeof(ifr->ifr_ifru.ifru_stat));
    }
    break;

  case SIOCGIFSTAT_ICMP6:         /* struct in6_ifreq */
    /* N.B.: if_inet6data is never freed once set. */
    if (IN6_IFEXTRA(ifp) == NULL) {
      /* return (EAFNOSUPPORT)? */
      bzero(&ifr->ifr_ifru.ifru_icmp6stat,
          sizeof(ifr->ifr_ifru.ifru_icmp6stat));
    } else {
      bcopy(&IN6_IFEXTRA(ifp)->icmp6_ifstat,
          &ifr->ifr_ifru.ifru_icmp6stat,
          sizeof(ifr->ifr_ifru.ifru_icmp6stat));
    }
    break;

  default:
    VERIFY(0);
    /* NOTREACHED */
  }

  return error;
}

/*
 * Caller passes in the ioctl data pointer directly via "ifr", with the
 * expectation that this routine always uses bcopy() or other byte-aligned
 * memory accesses.
 */
static __attribute__((noinline)) int
in6ctl_alifetime(struct in6_ifaddr *ia, u_long cmd, struct in6_ifreq *ifr,
    boolean_t p64)
{
  uint64_t timenow = net_uptime();
  struct in6_addrlifetime ia6_lt;
  struct timeval caltime;
  int error = 0;

  if (ia == NULL) {
    return EADDRNOTAVAIL;
  }

  switch (cmd) {
  case SIOCGIFALIFETIME_IN6:      /* struct in6_ifreq */
    IFA_LOCK(&ia->ia_ifa);
    /* retrieve time as calendar time (last arg is 1) */
    in6ifa_getlifetime(ia, &ia6_lt, 1);
    if (p64) {
      struct in6_addrlifetime_64 lt;

      bzero(&lt, sizeof(lt));
      lt.ia6t_expire = ia6_lt.ia6t_expire;
      lt.ia6t_preferred = ia6_lt.ia6t_preferred;
      lt.ia6t_vltime = ia6_lt.ia6t_vltime;
      lt.ia6t_pltime = ia6_lt.ia6t_pltime;
      bcopy(&lt, &ifr->ifr_ifru.ifru_lifetime, sizeof(ifr->ifr_ifru.ifru_lifetime));
    } else {
      struct in6_addrlifetime_32 lt;

      bzero(&lt, sizeof(lt));
      lt.ia6t_expire = (uint32_t)ia6_lt.ia6t_expire;
      lt.ia6t_preferred = (uint32_t)ia6_lt.ia6t_preferred;
      lt.ia6t_vltime = (uint32_t)ia6_lt.ia6t_vltime;
      lt.ia6t_pltime = (uint32_t)ia6_lt.ia6t_pltime;
      bcopy(&lt, &ifr->ifr_ifru.ifru_lifetime, sizeof(ifr->ifr_ifru.ifru_lifetime));
    }
    IFA_UNLOCK(&ia->ia_ifa);
    break;

  case SIOCSIFALIFETIME_IN6:      /* struct in6_ifreq */
    getmicrotime(&caltime);

    /* sanity for overflow - beware unsigned */
    if (p64) {
      struct in6_addrlifetime_64 lt;

      bcopy(&ifr->ifr_ifru.ifru_lifetime, &lt, sizeof(lt));
      if (lt.ia6t_vltime != ND6_INFINITE_LIFETIME &&
          lt.ia6t_vltime + caltime.tv_sec < caltime.tv_sec) {
        error = EINVAL;
        break;
      }
      if (lt.ia6t_pltime != ND6_INFINITE_LIFETIME &&
          lt.ia6t_pltime + caltime.tv_sec < caltime.tv_sec) {
        error = EINVAL;
        break;
      }
    } else {
      struct in6_addrlifetime_32 lt;

      bcopy(&ifr->ifr_ifru.ifru_lifetime, &lt, sizeof(lt));
      if (lt.ia6t_vltime != ND6_INFINITE_LIFETIME &&
          lt.ia6t_vltime + caltime.tv_sec < caltime.tv_sec) {
        error = EINVAL;
        break;
      }
      if (lt.ia6t_pltime != ND6_INFINITE_LIFETIME &&
          lt.ia6t_pltime + caltime.tv_sec < caltime.tv_sec) {
        error = EINVAL;
        break;
      }
    }

    IFA_LOCK(&ia->ia_ifa);
    if (p64) {
      struct in6_addrlifetime_64 lt;

      bcopy(&ifr->ifr_ifru.ifru_lifetime, &lt, sizeof(lt));
      ia6_lt.ia6t_expire = lt.ia6t_expire;
      ia6_lt.ia6t_preferred = lt.ia6t_preferred;
      ia6_lt.ia6t_vltime = lt.ia6t_vltime;
      ia6_lt.ia6t_pltime = lt.ia6t_pltime;
    } else {
      struct in6_addrlifetime_32 lt;

      bcopy(&ifr->ifr_ifru.ifru_lifetime, &lt, sizeof(lt));
      ia6_lt.ia6t_expire = (uint32_t)lt.ia6t_expire;
      ia6_lt.ia6t_preferred = (uint32_t)lt.ia6t_preferred;
      ia6_lt.ia6t_vltime = lt.ia6t_vltime;
      ia6_lt.ia6t_pltime = lt.ia6t_pltime;
    }
    /* for sanity */
    if (ia6_lt.ia6t_vltime != ND6_INFINITE_LIFETIME) {
      ia6_lt.ia6t_expire = timenow + ia6_lt.ia6t_vltime;
    } else {
      ia6_lt.ia6t_expire = 0;
    }

    if (ia6_lt.ia6t_pltime != ND6_INFINITE_LIFETIME) {
      ia6_lt.ia6t_preferred = timenow + ia6_lt.ia6t_pltime;
    } else {
      ia6_lt.ia6t_preferred = 0;
    }

    in6ifa_setlifetime(ia, &ia6_lt);
    IFA_UNLOCK(&ia->ia_ifa);
    break;

  default:
    VERIFY(0);
    /* NOTREACHED */
  }

  return error;
}

static int
in6ctl_clat46start(struct ifnet *ifp)
{
  struct nd_prefix *pr = NULL;
  struct nd_prefix *next = NULL;
  struct in6_ifaddr *ia6 = NULL;
  int error = 0;

  if (ifp == lo_ifp) {
    return EINVAL;
  }
  /*
   * Traverse the list of prefixes and find the first non-linklocal
   * prefix on the interface.
   * For that found eligible prefix, configure a CLAT46 reserved address.
   */
  lck_mtx_lock(nd6_mutex);
  for (pr = nd_prefix.lh_first; pr; pr = next) {
    next = pr->ndpr_next;

    NDPR_LOCK(pr);
    if (pr->ndpr_ifp != ifp) {
      NDPR_UNLOCK(pr);
      continue;
    }

    if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) {
      NDPR_UNLOCK(pr);
      continue; /* XXX */
    }

    if (pr->ndpr_raf_auto == 0) {
      NDPR_UNLOCK(pr);
      continue;
    }

    if (pr->ndpr_stateflags & NDPRF_DEFUNCT) {
      NDPR_UNLOCK(pr);
      continue;
    }

    if ((pr->ndpr_stateflags & NDPRF_CLAT46) == 0
        && pr->ndpr_vltime != 0) {
      NDPR_ADDREF(pr); /* Take reference for rest of the processing */
      NDPR_UNLOCK(pr);
      break;
    } else {
      NDPR_UNLOCK(pr);
      continue;
    }
  }
  lck_mtx_unlock(nd6_mutex);

  if (pr != NULL) {
    if ((ia6 = in6_pfx_newpersistaddr(pr, FALSE, &error,
        TRUE, CLAT46_COLLISION_COUNT_OFFSET)) == NULL) {
      nd6log0(error,
          "Could not configure CLAT46 address on"
          " interface %s.\n", ifp->if_xname);
    } else {
      IFA_LOCK(&ia6->ia_ifa);
      NDPR_LOCK(pr);
      ia6->ia6_ndpr = pr;
      NDPR_ADDREF(pr); /* for addr reference */
      pr->ndpr_stateflags |= NDPRF_CLAT46;
      pr->ndpr_addrcnt++;
      VERIFY(pr->ndpr_addrcnt != 0);
      NDPR_UNLOCK(pr);
      IFA_UNLOCK(&ia6->ia_ifa);
      IFA_REMREF(&ia6->ia_ifa);
      ia6 = NULL;
      /*
       * A newly added address might affect the status
       * of other addresses, so we check and update it.
       * XXX: what if address duplication happens?
       */
      lck_mtx_lock(nd6_mutex);
      pfxlist_onlink_check();
      lck_mtx_unlock(nd6_mutex);
    }
    NDPR_REMREF(pr);
  }
  return error;
}

#define ifa2ia6(ifa)    ((struct in6_ifaddr *)(void *)(ifa))

/*
 * Generic INET6 control operations (ioctl's).
 *
 * ifp is NULL if not an interface-specific ioctl.
 *
 * Most of the routines called to handle the ioctls would end up being
 * tail-call optimized, which unfortunately causes this routine to
 * consume too much stack space; this is the reason for the "noinline"
 * attribute used on those routines.
 *
 * If called directly from within the networking stack (as opposed to via
 * pru_control), the socket parameter may be NULL.
 */
int
in6_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp,
    struct proc *p)
{
  struct in6_ifreq *ifr = (struct in6_ifreq *)(void *)data;
  struct in6_aliasreq sifra, *ifra = NULL;
  struct in6_ifaddr *ia = NULL;
  struct sockaddr_in6 sin6, *sa6 = NULL;
  boolean_t privileged = (proc_suser(p) == 0);
  boolean_t p64 = proc_is64bit(p);
  boolean_t so_unlocked = FALSE;
  int intval, error = 0;

  /* In case it's NULL, make sure it came from the kernel */
  VERIFY(so != NULL || p == kernproc);

  /*
   * ioctls which don't require ifp, may require socket.
   */
  switch (cmd) {
  case SIOCAADDRCTL_POLICY:       /* struct in6_addrpolicy */
  case SIOCDADDRCTL_POLICY:       /* struct in6_addrpolicy */
    if (!privileged) {
      return EPERM;
    }
    return in6_src_ioctl(cmd, data);
  /* NOTREACHED */

  case SIOCDRADD_IN6_32:          /* struct in6_defrouter_32 */
  case SIOCDRADD_IN6_64:          /* struct in6_defrouter_64 */
  case SIOCDRDEL_IN6_32:          /* struct in6_defrouter_32 */
  case SIOCDRDEL_IN6_64:          /* struct in6_defrouter_64 */
    if (!privileged) {
      return EPERM;
    }
    return defrtrlist_ioctl(cmd, data);
  /* NOTREACHED */

  case SIOCGASSOCIDS32:           /* struct so_aidreq32 */
  case SIOCGASSOCIDS64:           /* struct so_aidreq64 */
    return in6ctl_associd(so, cmd, data);
  /* NOTREACHED */

  case SIOCGCONNIDS32:            /* struct so_cidreq32 */
  case SIOCGCONNIDS64:            /* struct so_cidreq64 */
    return in6ctl_connid(so, cmd, data);
  /* NOTREACHED */

  case SIOCGCONNINFO32:           /* struct so_cinforeq32 */
  case SIOCGCONNINFO64:           /* struct so_cinforeq64 */
    return in6ctl_conninfo(so, cmd, data);
    /* NOTREACHED */
  }

  /*
   * The rest of ioctls require ifp; reject if we don't have one;
   * return ENXIO to be consistent with ifioctl().
   */
  if (ifp == NULL) {
    return ENXIO;
  }

  /*
   * Unlock the socket since ifnet_ioctl() may be invoked by
   * one of the ioctl handlers below.  Socket will be re-locked
   * prior to returning.
   */
  if (so != NULL) {
    socket_unlock(so, 0);
    so_unlocked = TRUE;
  }

  /*
   * ioctls which require ifp but not interface address.
   */
  switch (cmd) {
  case SIOCAUTOCONF_START:        /* struct in6_ifreq */
    if (!privileged) {
      error = EPERM;
      goto done;
    }
    error = in6_autoconf(ifp, TRUE);
    goto done;

  case SIOCAUTOCONF_STOP:         /* struct in6_ifreq */
    if (!privileged) {
      error = EPERM;
      goto done;
    }
    error = in6_autoconf(ifp, FALSE);
    goto done;

  case SIOCLL_START_32:           /* struct in6_aliasreq_32 */
  case SIOCLL_START_64:           /* struct in6_aliasreq_64 */
    if (!privileged) {
      error = EPERM;
      goto done;
    }
    error = in6ctl_llstart(ifp, cmd, data);
    goto done;

  case SIOCLL_STOP:               /* struct in6_ifreq */
    if (!privileged) {
      error = EPERM;
      goto done;
    }
    error = in6ctl_llstop(ifp);
    goto done;

  case SIOCCLAT46_START:          /* struct in6_ifreq */
    if (!privileged) {
      error = EPERM;
      goto done;
    }
    error = in6ctl_clat46start(ifp);
    if (error == 0) {
      if_set_eflags(ifp, IFEF_CLAT46);
    }
    goto done;

  case SIOCCLAT46_STOP:           /* struct in6_ifreq */
    if (!privileged) {
      error = EPERM;
      goto done;
    }

    /*
     * Not much to be done here and it might not be needed
     * It would usually be done when IPv6 configuration is being
     * flushed.
     * XXX Probably STOP equivalent is not needed here.
     */
    if_clear_eflags(ifp, IFEF_CLAT46);
    goto done;
  case SIOCGETROUTERMODE_IN6:     /* struct in6_ifreq */
    intval = ifp->if_ipv6_router_mode;
    bcopy(&intval, &((struct in6_ifreq *)(void *)data)->ifr_intval,
        sizeof(intval));
    goto done;
  case SIOCSETROUTERMODE_IN6:     /* struct in6_ifreq */
    if (!privileged) {
      error = EPERM;
      goto done;
    }
    bcopy(&((struct in6_ifreq *)(void *)data)->ifr_intval,
        &intval, sizeof(intval));
    switch (intval) {
    case IPV6_ROUTER_MODE_DISABLED:
    case IPV6_ROUTER_MODE_EXCLUSIVE:
    case IPV6_ROUTER_MODE_HYBRID:
      break;
    default:
      error = EINVAL;
      goto done;
    }
    error = in6_setrouter(ifp, (ipv6_router_mode_t)intval);
    goto done;

  case SIOCPROTOATTACH_IN6_32:    /* struct in6_aliasreq_32 */
  case SIOCPROTOATTACH_IN6_64:    /* struct in6_aliasreq_64 */
    if (!privileged) {
      error = EPERM;
      goto done;
    }
    error = in6_domifattach(ifp);
    goto done;

  case SIOCPROTODETACH_IN6:       /* struct in6_ifreq */
    if (!privileged) {
      error = EPERM;
      goto done;
    }
    /* Cleanup interface routes and addresses */
    in6_purgeif(ifp);

    if ((error = proto_unplumb(PF_INET6, ifp))) {
      log(LOG_ERR, "SIOCPROTODETACH_IN6: %s error=%d\n",
          if_name(ifp), error);
    }
    goto done;

  case SIOCSNDFLUSH_IN6:          /* struct in6_ifreq */
  case SIOCSPFXFLUSH_IN6:         /* struct in6_ifreq */
  case SIOCSRTRFLUSH_IN6:         /* struct in6_ifreq */
  case SIOCSDEFIFACE_IN6_32:      /* struct in6_ndifreq_32 */
  case SIOCSDEFIFACE_IN6_64:      /* struct in6_ndifreq_64 */
  case SIOCSIFINFO_FLAGS:         /* struct in6_ndireq */
  case SIOCGIFCGAPREP_IN6_32:     /* struct in6_cgareq_32 */
  case SIOCGIFCGAPREP_IN6_64:     /* struct in6_cgareq_64 */
  case SIOCSIFCGAPREP_IN6_32:     /* struct in6_cgareq_32 */
  case SIOCSIFCGAPREP_IN6_64:     /* struct in6_cgareq_32 */
    if (!privileged) {
      error = EPERM;
      goto done;
    }
    OS_FALLTHROUGH;
  case OSIOCGIFINFO_IN6:          /* struct in6_ondireq */
  case SIOCGIFINFO_IN6:           /* struct in6_ondireq */
  case SIOCGDRLST_IN6_32:         /* struct in6_drlist_32 */
  case SIOCGDRLST_IN6_64:         /* struct in6_drlist_64 */
  case SIOCGPRLST_IN6_32:         /* struct in6_prlist_32 */
  case SIOCGPRLST_IN6_64:         /* struct in6_prlist_64 */
  case SIOCGNBRINFO_IN6_32:       /* struct in6_nbrinfo_32 */
  case SIOCGNBRINFO_IN6_64:       /* struct in6_nbrinfo_64 */
  case SIOCGDEFIFACE_IN6_32:      /* struct in6_ndifreq_32 */
  case SIOCGDEFIFACE_IN6_64:      /* struct in6_ndifreq_64 */
    error = nd6_ioctl(cmd, data, ifp);
    goto done;

  case SIOCSIFPREFIX_IN6:         /* struct in6_prefixreq (deprecated) */
  case SIOCDIFPREFIX_IN6:         /* struct in6_prefixreq (deprecated) */
  case SIOCAIFPREFIX_IN6:         /* struct in6_rrenumreq (deprecated) */
  case SIOCCIFPREFIX_IN6:         /* struct in6_rrenumreq (deprecated) */
  case SIOCSGIFPREFIX_IN6:        /* struct in6_rrenumreq (deprecated) */
  case SIOCGIFPREFIX_IN6:         /* struct in6_prefixreq (deprecated) */
    log(LOG_NOTICE,
        "prefix ioctls are now invalidated. "
        "please use ifconfig.\n");
    error = EOPNOTSUPP;
    goto done;

  case SIOCSSCOPE6:               /* struct in6_ifreq (deprecated) */
  case SIOCGSCOPE6:               /* struct in6_ifreq (deprecated) */
  case SIOCGSCOPE6DEF:            /* struct in6_ifreq (deprecated) */
    error = EOPNOTSUPP;
    goto done;

  case SIOCLL_CGASTART_32:        /* struct in6_cgareq_32 */
  case SIOCLL_CGASTART_64:        /* struct in6_cgareq_64 */
    if (!privileged) {
      error = EPERM;
    } else {
      error = in6ctl_cgastart(ifp, cmd, data);
    }
    goto done;

  case SIOCGIFSTAT_IN6:           /* struct in6_ifreq */
  case SIOCGIFSTAT_ICMP6:         /* struct in6_ifreq */
    error = in6ctl_gifstat(ifp, cmd, ifr);
    goto done;
  }

  /*
   * ioctls which require interface address; obtain sockaddr_in6.
   */
  switch (cmd) {
  case SIOCSIFADDR_IN6:           /* struct in6_ifreq (deprecated) */
  case SIOCSIFDSTADDR_IN6:        /* struct in6_ifreq (deprecated) */
  case SIOCSIFNETMASK_IN6:        /* struct in6_ifreq (deprecated) */
    /*
     * Since IPv6 allows a node to assign multiple addresses
     * on a single interface, SIOCSIFxxx ioctls are deprecated.
     */
    /* we decided to obsolete this command (20000704) */
    error = EOPNOTSUPP;
    goto done;

  case SIOCAIFADDR_IN6_32:        /* struct in6_aliasreq_32 */
  case SIOCAIFADDR_IN6_64:        /* struct in6_aliasreq_64 */
    if (!privileged) {
      error = EPERM;
      goto done;
    }
    /*
     * Convert user ifra to the kernel form, when appropriate.
     * This allows the conversion between different data models
     * to be centralized, so that it can be passed around to other
     * routines that are expecting the kernel form.
     */
    ifra = in6_aliasreq_to_native(data,
        (cmd == SIOCAIFADDR_IN6_64), &sifra);
    bcopy(&ifra->ifra_addr, &sin6, sizeof(sin6));
    sa6 = &sin6;
    break;

  case SIOCDIFADDR_IN6:           /* struct in6_ifreq */
  case SIOCSIFALIFETIME_IN6:      /* struct in6_ifreq */
    if (!privileged) {
      error = EPERM;
      goto done;
    }
    OS_FALLTHROUGH;
  case SIOCGIFADDR_IN6:           /* struct in6_ifreq */
  case SIOCGIFDSTADDR_IN6:        /* struct in6_ifreq */
  case SIOCGIFNETMASK_IN6:        /* struct in6_ifreq */
  case SIOCGIFAFLAG_IN6:          /* struct in6_ifreq */
  case SIOCGIFALIFETIME_IN6:      /* struct in6_ifreq */
    bcopy(&ifr->ifr_addr, &sin6, sizeof(sin6));
    sa6 = &sin6;
    break;
  case SIOCGIFDSTADDR:
  case SIOCSIFDSTADDR:
  case SIOCGIFBRDADDR:
  case SIOCSIFBRDADDR:
  case SIOCGIFNETMASK:
  case SIOCSIFNETMASK:
  case SIOCGIFADDR:
  case SIOCSIFADDR:
  case SIOCAIFADDR:
  case SIOCDIFADDR:
    /* Do not handle these AF_INET commands in AF_INET6 path */
    error = EINVAL;
    goto done;
  }

  /*
   * Find address for this interface, if it exists.
   *
   * In netinet code, we have checked ifra_addr in SIOCSIF*ADDR operation
   * only, and used the first interface address as the target of other
   * operations (without checking ifra_addr).  This was because netinet
   * code/API assumed at most 1 interface address per interface.
   * Since IPv6 allows a node to assign multiple addresses
   * on a single interface, we almost always look and check the
   * presence of ifra_addr, and reject invalid ones here.
   * It also decreases duplicated code among SIOC*_IN6 operations.
   */
  VERIFY(ia == NULL);
  if (sa6 != NULL && sa6->sin6_family == AF_INET6) {
    if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) {
      if (sa6->sin6_addr.s6_addr16[1] == 0) {
        /* link ID is not embedded by the user */
        sa6->sin6_addr.s6_addr16[1] =
            htons(ifp->if_index);
      } else if (sa6->sin6_addr.s6_addr16[1] !=
          htons(ifp->if_index)) {
        error = EINVAL; /* link ID contradicts */
        goto done;
      }
      if (sa6->sin6_scope_id) {
        if (sa6->sin6_scope_id !=
            (u_int32_t)ifp->if_index) {
          error = EINVAL;
          goto done;
        }
        sa6->sin6_scope_id = 0; /* XXX: good way? */
      }
    }
    /*
     * Any failures from this point on must take into account
     * a non-NULL "ia" with an outstanding reference count, and
     * therefore requires IFA_REMREF.  Jump to "done" label
     * instead of calling return if "ia" is valid.
     */
    ia = in6ifa_ifpwithaddr(ifp, &sa6->sin6_addr);
  }

  /*
   * SIOCDIFADDR_IN6/SIOCAIFADDR_IN6 specific tests.
   */
  switch (cmd) {
  case SIOCDIFADDR_IN6:           /* struct in6_ifreq */
    if (ia == NULL) {
      error = EADDRNOTAVAIL;
      goto done;
    }
    OS_FALLTHROUGH;
  case SIOCAIFADDR_IN6_32:        /* struct in6_aliasreq_32 */
  case SIOCAIFADDR_IN6_64:        /* struct in6_aliasreq_64 */
    VERIFY(sa6 != NULL);
    /*
     * We always require users to specify a valid IPv6 address for
     * the corresponding operation.  Use "sa6" instead of "ifra"
     * since SIOCDIFADDR_IN6 falls thru above.
     */
    if (sa6->sin6_family != AF_INET6 ||
        sa6->sin6_len != sizeof(struct sockaddr_in6)) {
      error = EAFNOSUPPORT;
      goto done;
    }
    break;
  }

  /*
   * And finally process address-related ioctls.
   */
  switch (cmd) {
  case SIOCGIFADDR_IN6:           /* struct in6_ifreq */
  /* This interface is basically deprecated. use SIOCGIFCONF. */
  /* FALLTHRU */
  case SIOCGIFDSTADDR_IN6:        /* struct in6_ifreq */
    error = in6ctl_gifaddr(ifp, ia, cmd, ifr);
    break;

  case SIOCGIFNETMASK_IN6:        /* struct in6_ifreq */
    if (ia != NULL) {
      IFA_LOCK(&ia->ia_ifa);
      bcopy(&ia->ia_prefixmask, &ifr->ifr_addr,
          sizeof(struct sockaddr_in6));
      IFA_UNLOCK(&ia->ia_ifa);
    } else {
      error = EADDRNOTAVAIL;
    }
    break;

  case SIOCGIFAFLAG_IN6:          /* struct in6_ifreq */
    if (ia != NULL) {
      IFA_LOCK(&ia->ia_ifa);
      bcopy(&ia->ia6_flags, &ifr->ifr_ifru.ifru_flags6,
          sizeof(ifr->ifr_ifru.ifru_flags6));
      IFA_UNLOCK(&ia->ia_ifa);
    } else {
      error = EADDRNOTAVAIL;
    }
    break;

  case SIOCGIFALIFETIME_IN6:      /* struct in6_ifreq */
  case SIOCSIFALIFETIME_IN6:      /* struct in6_ifreq */
    error = in6ctl_alifetime(ia, cmd, ifr, p64);
    break;

  case SIOCAIFADDR_IN6_32:        /* struct in6_aliasreq_32 */
  case SIOCAIFADDR_IN6_64:        /* struct in6_aliasreq_64 */
    error = in6ctl_aifaddr(ifp, ifra);
    break;

  case SIOCDIFADDR_IN6:
    in6ctl_difaddr(ifp, ia);
    break;

  default:
    error = ifnet_ioctl(ifp, PF_INET6, cmd, data);
    break;
  }

done:
  if (ia != NULL) {
    IFA_REMREF(&ia->ia_ifa);
  }
  if (so_unlocked) {
    socket_lock(so, 0);
  }

  return error;
}

static __attribute__((noinline)) int
in6ctl_aifaddr(struct ifnet *ifp, struct in6_aliasreq *ifra)
{
  int i, error, addtmp;
  uint8_t plen;
  struct nd_prefix pr0, *pr;
  struct in6_ifaddr *ia;

  VERIFY(ifp != NULL && ifra != NULL);
  ia = NULL;

  /* Attempt to attach the protocol, in case it isn't attached */
  error = in6_domifattach(ifp);
  if (error == 0) {
    /* PF_INET6 wasn't previously attached */
    error = in6_ifattach_aliasreq(ifp, NULL, NULL);
    if (error != 0) {
      goto done;
    }

    in6_if_up_dad_start(ifp);
  } else if (error != EEXIST) {
    goto done;
  }

  /*
   * First, make or update the interface address structure, and link it
   * to the list.
   */
  error = in6_update_ifa(ifp, ifra, 0, &ia);
  if (error != 0) {
    goto done;
  }
  VERIFY(ia != NULL);

  /* Now, make the prefix on-link on the interface. */
  plen = (uint8_t)in6_mask2len(&ifra->ifra_prefixmask.sin6_addr, NULL);
  if (plen == 128) {
    goto done;
  }

  /*
   * NOTE: We'd rather create the prefix before the address, but we need
   * at least one address to install the corresponding interface route,
   * so we configure the address first.
   */

  /*
   * Convert mask to prefix length (prefixmask has already been validated
   * in in6_update_ifa().
   */
  bzero(&pr0, sizeof(pr0));
  pr0.ndpr_plen = plen;
  pr0.ndpr_ifp = ifp;
  pr0.ndpr_prefix = ifra->ifra_addr;
  pr0.ndpr_mask = ifra->ifra_prefixmask.sin6_addr;

  /* apply the mask for safety. */
  for (i = 0; i < 4; i++) {
    pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
        ifra->ifra_prefixmask.sin6_addr.s6_addr32[i];
  }

  /*
   * Since we don't have an API to set prefix (not address) lifetimes, we
   * just use the same lifetimes as addresses. The (temporarily)
   * installed lifetimes can be overridden by later advertised RAs (when
   * accept_rtadv is non 0), which is an intended behavior.
   */
  pr0.ndpr_raf_onlink = 1; /* should be configurable? */
  pr0.ndpr_raf_auto = !!(ifra->ifra_flags & IN6_IFF_AUTOCONF);
  if (ifra->ifra_flags & (IN6_IFF_AUTOCONF | IN6_IFF_DYNAMIC)) {
    pr0.ndpr_vltime = ifra->ifra_lifetime.ia6t_vltime;
    pr0.ndpr_pltime = ifra->ifra_lifetime.ia6t_pltime;
  } else {
    pr0.ndpr_vltime = ND6_INFINITE_LIFETIME;
    pr0.ndpr_pltime = ND6_INFINITE_LIFETIME;
  }
  pr0.ndpr_stateflags |= NDPRF_STATIC;
  lck_mtx_init(&pr0.ndpr_lock, ifa_mtx_grp, ifa_mtx_attr);

  /* add the prefix if there's none. */
  if ((pr = nd6_prefix_lookup(&pr0, ND6_PREFIX_EXPIRY_NEVER)) == NULL) {
    /*
     * nd6_prelist_add will install the corresponding interface
     * route.
     */
    error = nd6_prelist_add(&pr0, NULL, &pr, FALSE);
    if (error != 0) {
      goto done;
    }

    if (pr == NULL) {
      log(LOG_ERR, "%s: nd6_prelist_add okay, but"
          " no prefix.\n", __func__);
      error = EINVAL;
      goto done;
    }
  }

  IFA_LOCK(&ia->ia_ifa);

  /* if this is a new autoconfed addr */
  addtmp = FALSE;
  if (ia->ia6_ndpr == NULL) {
    NDPR_LOCK(pr);
    ++pr->ndpr_addrcnt;
    VERIFY(pr->ndpr_addrcnt != 0);
    ia->ia6_ndpr = pr;
    NDPR_ADDREF(pr); /* for addr reference */

    /*
     * If this is the first autoconf address from the prefix,
     * create a temporary address as well (when specified).
     */
    if ((ia->ia6_flags & IN6_IFF_AUTOCONF) != 0 &&
        ip6_use_tempaddr &&
        pr->ndpr_addrcnt == 1 &&
        (!IN6_IS_ADDR_UNIQUE_LOCAL(&ia->ia_addr.sin6_addr)
        || ip6_ula_use_tempaddr)) {
      addtmp = true;
    }
    NDPR_UNLOCK(pr);
  }

  IFA_UNLOCK(&ia->ia_ifa);

  if (addtmp) {
    int e;
    e = in6_tmpifadd(ia, 1);
    if (e != 0) {
      log(LOG_NOTICE, "%s: failed to create a"
          " temporary address, error=%d\n",
          __func__, e);
    }
  }

  /*
   * This might affect the status of autoconfigured addresses, that is,
   * this address might make other addresses detached.
   */
  lck_mtx_lock(nd6_mutex);
  pfxlist_onlink_check();
  lck_mtx_unlock(nd6_mutex);

  /* Drop use count held above during lookup/add */
  NDPR_REMREF(pr);

done:
  if (ia != NULL) {
    IFA_REMREF(&ia->ia_ifa);
  }
  return error;
}

static __attribute__((noinline)) void
in6ctl_difaddr(struct ifnet *ifp, struct in6_ifaddr *ia)
{
  int i = 0;
  struct nd_prefix pr0, *pr;

  VERIFY(ifp != NULL && ia != NULL);

  /*
   * If the address being deleted is the only one that owns
   * the corresponding prefix, expire the prefix as well.
   * XXX: theoretically, we don't have to worry about such
   * relationship, since we separate the address management
   * and the prefix management.  We do this, however, to provide
   * as much backward compatibility as possible in terms of
   * the ioctl operation.
   * Note that in6_purgeaddr() will decrement ndpr_addrcnt.
   */
  IFA_LOCK(&ia->ia_ifa);
  bzero(&pr0, sizeof(pr0));
  pr0.ndpr_ifp = ifp;
  pr0.ndpr_plen = (uint8_t)in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL);
  if (pr0.ndpr_plen == 128) {
    IFA_UNLOCK(&ia->ia_ifa);
    goto purgeaddr;
  }
  pr0.ndpr_prefix = ia->ia_addr;
  pr0.ndpr_mask = ia->ia_prefixmask.sin6_addr;
  for (i = 0; i < 4; i++) {
    pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
        ia->ia_prefixmask.sin6_addr.s6_addr32[i];
  }
  IFA_UNLOCK(&ia->ia_ifa);

  if ((pr = nd6_prefix_lookup(&pr0, ND6_PREFIX_EXPIRY_UNSPEC)) != NULL) {
    IFA_LOCK(&ia->ia_ifa);
    NDPR_LOCK(pr);
    if (pr->ndpr_addrcnt == 1) {
      /* XXX: just for expiration */
      pr->ndpr_expire = 1;
    }
    NDPR_UNLOCK(pr);
    IFA_UNLOCK(&ia->ia_ifa);

    /* Drop use count held above during lookup */
    NDPR_REMREF(pr);
  }

purgeaddr:
  in6_purgeaddr(&ia->ia_ifa);
}

static __attribute__((noinline)) int
in6_autoconf(struct ifnet *ifp, int enable)
{
  int error = 0;

  VERIFY(ifp != NULL);

  if (ifp->if_flags & IFF_LOOPBACK) {
    return EINVAL;
  }

  if (enable) {
    /*
     * An interface in IPv6 router mode implies that it
     * is either configured with a static IP address or
     * autoconfigured via a locally-generated RA.  Prevent
     * SIOCAUTOCONF_START from being set in that mode.
     */
    ifnet_lock_exclusive(ifp);
    if (ifp->if_ipv6_router_mode == IPV6_ROUTER_MODE_EXCLUSIVE) {
      if_clear_eflags(ifp, IFEF_ACCEPT_RTADV);
      error = EBUSY;
    } else {
      if_set_eflags(ifp, IFEF_ACCEPT_RTADV);
    }
    ifnet_lock_done(ifp);
  } else {
    struct in6_ifaddr *ia = NULL;

    if_clear_eflags(ifp, IFEF_ACCEPT_RTADV);

    /* Remove autoconfigured address from interface */
    lck_rw_lock_exclusive(&in6_ifaddr_rwlock);
    boolean_t from_begining = TRUE;
    while (from_begining) {
      from_begining = FALSE;
      TAILQ_FOREACH(ia, &in6_ifaddrhead, ia6_link) {
        if (ia->ia_ifa.ifa_ifp != ifp) {
          continue;
        }
        IFA_LOCK(&ia->ia_ifa);
        if (ia->ia6_flags & IN6_IFF_AUTOCONF) {
          IFA_ADDREF_LOCKED(&ia->ia_ifa); /* for us */
          IFA_UNLOCK(&ia->ia_ifa);
          lck_rw_done(&in6_ifaddr_rwlock);
          in6_purgeaddr(&ia->ia_ifa);
          IFA_REMREF(&ia->ia_ifa);        /* for us */
          lck_rw_lock_exclusive(&in6_ifaddr_rwlock);
          /*
           * Purging the address caused in6_ifaddr_rwlock
           * to be dropped and reacquired;
           * therefore search again from the beginning
           * of in6_ifaddrs list.
           */
          from_begining = TRUE;
          break;
        }
        IFA_UNLOCK(&ia->ia_ifa);
      }
    }
    lck_rw_done(&in6_ifaddr_rwlock);
  }
  return error;
}

/*
 * Handle SIOCSETROUTERMODE_IN6 to set the IPv6 router mode on the interface
 * Entering or exiting IPV6_ROUTER_MODE_EXCLUSIVE will result in the removal of
 * autoconfigured IPv6 addresses on the interface.
 */
static __attribute__((noinline)) int
in6_setrouter(struct ifnet *ifp, ipv6_router_mode_t mode)
{
  int                     error = 0;
  ipv6_router_mode_t      prev_mode;

  VERIFY(ifp != NULL);

  if (ifp->if_flags & IFF_LOOPBACK) {
    return ENODEV;
  }

  prev_mode = ifp->if_ipv6_router_mode;
  if (prev_mode == mode) {
    /* no mode change, there's nothing to do */
    return 0;
  }
  if (mode == IPV6_ROUTER_MODE_EXCLUSIVE) {
    struct nd_ifinfo *ndi = NULL;

    ndi = ND_IFINFO(ifp);
    if (ndi != NULL && ndi->initialized) {
      lck_mtx_lock(&ndi->lock);
      if (ndi->flags & ND6_IFF_PROXY_PREFIXES) {
        /* No proxy if we are an advertising router */
        ndi->flags &= ~ND6_IFF_PROXY_PREFIXES;
        lck_mtx_unlock(&ndi->lock);
        (void) nd6_if_prproxy(ifp, FALSE);
      } else {
        lck_mtx_unlock(&ndi->lock);
      }
    }
  }

  ifp->if_ipv6_router_mode = mode;
  lck_mtx_lock(nd6_mutex);
  defrouter_select(ifp, NULL);
  lck_mtx_unlock(nd6_mutex);
  if_allmulti(ifp, (mode == IPV6_ROUTER_MODE_EXCLUSIVE));
  if (mode == IPV6_ROUTER_MODE_EXCLUSIVE ||
      (prev_mode == IPV6_ROUTER_MODE_EXCLUSIVE
      && mode == IPV6_ROUTER_MODE_DISABLED)) {
    error = in6_autoconf(ifp, FALSE);
  }
  return error;
}

static int
in6_to_kamescope(struct sockaddr_in6 *sin6, struct ifnet *ifp)
{
  struct sockaddr_in6 tmp;
  int error, id;

  VERIFY(sin6 != NULL);
  tmp = *sin6;

  error = in6_recoverscope(&tmp, &sin6->sin6_addr, ifp);
  if (error != 0) {
    return error;
  }

  id = in6_addr2scopeid(ifp, &tmp.sin6_addr);
  if (tmp.sin6_scope_id == 0) {
    tmp.sin6_scope_id = id;
  } else if (tmp.sin6_scope_id != id) {
    return EINVAL; /* scope ID mismatch. */
  }
  error = in6_embedscope(&tmp.sin6_addr, &tmp, NULL, NULL, NULL);
  if (error != 0) {
    return error;
  }

  tmp.sin6_scope_id = 0;
  *sin6 = tmp;
  return 0;
}

/*
 * When the address is being configured we should clear out certain flags
 * coming in from the caller.
 */
#define IN6_IFF_CLR_ADDR_FLAG_MASK      (~(IN6_IFF_DEPRECATED | IN6_IFF_DETACHED | IN6_IFF_DUPLICATED))

static int
in6_ifaupdate_aux(struct in6_ifaddr *ia, struct ifnet *ifp, int ifaupflags)
{
  struct sockaddr_in6 mltaddr, mltmask;
  struct in6_addr llsol;
  struct ifaddr *ifa;
  struct in6_multi *in6m_sol;
  struct in6_multi_mship *imm;
  struct rtentry *rt;
  int delay, error = 0;

  VERIFY(ifp != NULL && ia != NULL);
  ifa = &ia->ia_ifa;
  in6m_sol = NULL;

  nd6log2(debug, "%s - %s ifp %s ia6_flags 0x%x ifaupflags 0x%x\n",
      __func__,
      ip6_sprintf(&ia->ia_addr.sin6_addr),
      if_name(ia->ia_ifp),
      ia->ia6_flags,
      ifaupflags);

  /*
   * Just to be safe, always clear certain flags when address
   * is being configured
   */
  ia->ia6_flags &= IN6_IFF_CLR_ADDR_FLAG_MASK;

  /*
   * Mark the address as tentative before joining multicast addresses,
   * so that corresponding MLD responses would not have a tentative
   * source address.
   */
  if (in6if_do_dad(ifp)) {
    in6_ifaddr_set_dadprogress(ia);
    /*
     * Do not delay sending neighbor solicitations when using optimistic
     * duplicate address detection, c.f. RFC 4429.
     */
    if (ia->ia6_flags & IN6_IFF_OPTIMISTIC) {
      ifaupflags &= ~IN6_IFAUPDATE_DADDELAY;
    } else {
      ifaupflags |= IN6_IFAUPDATE_DADDELAY;
    }
  } else {
    /*
     * If the interface has been marked to not perform
     * DAD, make sure to reset DAD in progress flags
     * that may come in from the caller.
     */
    ia->ia6_flags &= ~IN6_IFF_DADPROGRESS;
  }

  /* Join necessary multicast groups */
  if ((ifp->if_flags & IFF_MULTICAST) != 0) {
    /* join solicited multicast addr for new host id */
    bzero(&llsol, sizeof(struct in6_addr));
    llsol.s6_addr32[0] = IPV6_ADDR_INT32_MLL;
    llsol.s6_addr32[1] = 0;
    llsol.s6_addr32[2] = htonl(1);
    llsol.s6_addr32[3] = ia->ia_addr.sin6_addr.s6_addr32[3];
    llsol.s6_addr8[12] = 0xff;
    if ((error = in6_setscope(&llsol, ifp, NULL)) != 0) {
      /* XXX: should not happen */
      log(LOG_ERR, "%s: in6_setscope failed\n", __func__);
      goto unwind;
    }
    delay = 0;
    if ((ifaupflags & IN6_IFAUPDATE_DADDELAY)) {
      /*
       * We need a random delay for DAD on the address
       * being configured.  It also means delaying
       * transmission of the corresponding MLD report to
       * avoid report collision. [RFC 4862]
       */
      delay = random() % MAX_RTR_SOLICITATION_DELAY;
    }
    imm = in6_joingroup(ifp, &llsol, &error, delay);
    if (imm == NULL) {
      nd6log(info,
          "%s: addmulti failed for %s on %s (errno=%d)\n",
          __func__, ip6_sprintf(&llsol), if_name(ifp),
          error);
      VERIFY(error != 0);
      goto unwind;
    }
    in6m_sol = imm->i6mm_maddr;
    /* take a refcount for this routine */
    IN6M_ADDREF(in6m_sol);

    IFA_LOCK_SPIN(ifa);
    LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
    IFA_UNLOCK(ifa);

    bzero(&mltmask, sizeof(mltmask));
    mltmask.sin6_len = sizeof(struct sockaddr_in6);
    mltmask.sin6_family = AF_INET6;
    mltmask.sin6_addr = in6mask32;
#define MLTMASK_LEN  4  /* mltmask's masklen (=32bit=4octet) */

    /*
     * join link-local all-nodes address
     */
    bzero(&mltaddr, sizeof(mltaddr));
    mltaddr.sin6_len = sizeof(struct sockaddr_in6);
    mltaddr.sin6_family = AF_INET6;
    mltaddr.sin6_addr = in6addr_linklocal_allnodes;
    if ((error = in6_setscope(&mltaddr.sin6_addr, ifp, NULL)) != 0) {
      goto unwind; /* XXX: should not fail */
    }
    /*
     * XXX: do we really need this automatic routes?
     * We should probably reconsider this stuff.  Most applications
     * actually do not need the routes, since they usually specify
     * the outgoing interface.
     */
    rt = rtalloc1_scoped((struct sockaddr *)&mltaddr, 0, 0UL,
        ia->ia_ifp->if_index);
    if (rt) {
      if (memcmp(&mltaddr.sin6_addr, &((struct sockaddr_in6 *)
          (void *)rt_key(rt))->sin6_addr, MLTMASK_LEN)) {
        rtfree(rt);
        rt = NULL;
      }
    }
    if (!rt) {
      error = rtrequest_scoped(RTM_ADD,
          (struct sockaddr *)&mltaddr,
          (struct sockaddr *)&ia->ia_addr,
          (struct sockaddr *)&mltmask, RTF_UP | RTF_CLONING,
          NULL, ia->ia_ifp->if_index);
      if (error) {
        goto unwind;
      }
    } else {
      rtfree(rt);
    }

    imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error, 0);
    if (!imm) {
      nd6log(info,
          "%s: addmulti failed for %s on %s (errno=%d)\n",
          __func__, ip6_sprintf(&mltaddr.sin6_addr),
          if_name(ifp), error);
      VERIFY(error != 0);
      goto unwind;
    }
    IFA_LOCK_SPIN(ifa);
    LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
    IFA_UNLOCK(ifa);

    /*
     * join node information group address
     */
#define hostnamelen     strlen(hostname)
    delay = 0;
    if ((ifaupflags & IN6_IFAUPDATE_DADDELAY)) {
      /*
       * The spec doesn't say anything about delay for this
       * group, but the same logic should apply.
       */
      delay = random() % MAX_RTR_SOLICITATION_DELAY;
    }
    lck_mtx_lock(&hostname_lock);
    int n = in6_nigroup(ifp, hostname, hostnamelen, &mltaddr.sin6_addr);
    lck_mtx_unlock(&hostname_lock);
    if (n == 0) {
      imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error,
          delay); /* XXX jinmei */
      if (!imm) {
        nd6log(info,
            "%s: addmulti failed for %s on %s "
            "(errno=%d)\n",
            __func__, ip6_sprintf(&mltaddr.sin6_addr),
            if_name(ifp), error);
        /* XXX not very fatal, go on... */
        error = 0;
      } else {
        IFA_LOCK_SPIN(ifa);
        LIST_INSERT_HEAD(&ia->ia6_memberships,
            imm, i6mm_chain);
        IFA_UNLOCK(ifa);
      }
    }
#undef hostnamelen

    /*
     * join interface-local all-nodes address.
     * (ff01::1%ifN, and ff01::%ifN/32)
     */
    mltaddr.sin6_addr = in6addr_nodelocal_allnodes;
    if ((error = in6_setscope(&mltaddr.sin6_addr, ifp, NULL)) != 0) {
      goto unwind; /* XXX: should not fail */
    }
    /* XXX: again, do we really need the route? */
    rt = rtalloc1_scoped((struct sockaddr *)&mltaddr, 0, 0UL,
        ia->ia_ifp->if_index);
    if (rt) {
      if (memcmp(&mltaddr.sin6_addr, &((struct sockaddr_in6 *)
          (void *)rt_key(rt))->sin6_addr, MLTMASK_LEN)) {
        rtfree(rt);
        rt = NULL;
      }
    }
    if (!rt) {
      error = rtrequest_scoped(RTM_ADD,
          (struct sockaddr *)&mltaddr,
          (struct sockaddr *)&ia->ia_addr,
          (struct sockaddr *)&mltmask, RTF_UP | RTF_CLONING,
          NULL, ia->ia_ifp->if_index);
      if (error) {
        goto unwind;
      }
    } else {
      rtfree(rt);
    }

    imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error, 0);
    if (!imm) {
      nd6log(info,
          "%s: addmulti failed for %s on %s (errno=%d)\n",
          __func__, ip6_sprintf(&mltaddr.sin6_addr),
          if_name(ifp), error);
      VERIFY(error != 0);
      goto unwind;
    }
    IFA_LOCK(ifa);
    LIST_INSERT_HEAD(&ia->ia6_memberships, imm, i6mm_chain);
    IFA_UNLOCK(ifa);
#undef  MLTMASK_LEN

    /*
     * create a ff00::/8 route
     */
    bzero(&mltmask, sizeof(mltmask));
    mltmask.sin6_len = sizeof(struct sockaddr_in6);
    mltmask.sin6_family = AF_INET6;
    mltmask.sin6_addr = in6mask8;
#define MLTMASK_LEN_8_BITS  1  /* ff00::/8 mltmask's masklen (=8bit=1octet) */

    bzero(&mltaddr, sizeof(mltaddr));
    mltaddr.sin6_len = sizeof(struct sockaddr_in6);
    mltaddr.sin6_family = AF_INET6;
    mltaddr.sin6_addr = in6addr_multicast_prefix;

    rt = rtalloc1_scoped((struct sockaddr *)&mltaddr, 0, 0UL,
        ia->ia_ifp->if_index);
    if (rt) {
      if (memcmp(&mltaddr.sin6_addr, &((struct sockaddr_in6 *)
          (void *)rt_key(rt))->sin6_addr, MLTMASK_LEN_8_BITS)) {
        rtfree(rt);
        rt = NULL;
      }
    }
    if (!rt) {
      error = rtrequest_scoped(RTM_ADD,
          (struct sockaddr *)&mltaddr,
          (struct sockaddr *)&ia->ia_addr,
          (struct sockaddr *)&mltmask, RTF_UP | RTF_CLONING,
          NULL, ia->ia_ifp->if_index);
      if (error) {
        goto unwind;
      }
    } else {
      rtfree(rt);
    }
  }
#undef  MLTMASK_LEN_8_BITS

  /* Ensure nd6_service() is scheduled as soon as it's convenient */
  ++nd6_sched_timeout_want;

  /*
   * Perform DAD, if:
   * * Interface is marked to perform DAD, AND
   * * Address is not marked to skip DAD, AND
   * * Address is in a pre-DAD state (Tentative or Optimistic)
   */
  IFA_LOCK_SPIN(ifa);
  if (in6if_do_dad(ifp) && (ia->ia6_flags & IN6_IFF_NODAD) == 0 &&
      (ia->ia6_flags & IN6_IFF_DADPROGRESS) != 0) {
    int mindelay, maxdelay;
    int *delayptr, delayval;

    IFA_UNLOCK(ifa);
    delayptr = NULL;
    /*
     * Avoid the DAD delay if the caller wants us to skip it.
     * This is not compliant with RFC 2461, but it's only being
     * used for signalling and not for actual DAD.
     */
    if ((ifaupflags & IN6_IFAUPDATE_DADDELAY) &&
        !(ia->ia6_flags & IN6_IFF_SWIFTDAD)) {
      /*
       * We need to impose a delay before sending an NS
       * for DAD.  Check if we also needed a delay for the
       * corresponding MLD message.  If we did, the delay
       * should be larger than the MLD delay (this could be
       * relaxed a bit, but this simple logic is at least
       * safe).
       */
      mindelay = 0;
      if (in6m_sol != NULL) {
        IN6M_LOCK(in6m_sol);
        if (in6m_sol->in6m_state ==
            MLD_REPORTING_MEMBER) {
          mindelay = in6m_sol->in6m_timer;
        }
        IN6M_UNLOCK(in6m_sol);
      }
      maxdelay = MAX_RTR_SOLICITATION_DELAY * hz;
      if (maxdelay - mindelay == 0) {
        delayval = 0;
      } else {
        delayval =
            (random() % (maxdelay - mindelay)) +
            mindelay;
      }
      delayptr = &delayval;
    }

    nd6_dad_start((struct ifaddr *)ia, delayptr);
  } else {
    IFA_UNLOCK(ifa);
  }

  goto done;

unwind:
  VERIFY(error != 0);
  in6_purgeaddr(&ia->ia_ifa);

done:
  /* release reference held for this routine */
  if (in6m_sol != NULL) {
    IN6M_REMREF(in6m_sol);
  }
  return error;
}

/*
 * Request an IPv6 interface address.  If the address is new, then it will be
 * constructed and appended to the interface address chains.  The interface
 * address structure is optionally returned with a reference for the caller.
 */
int
in6_update_ifa(struct ifnet *ifp, struct in6_aliasreq *ifra, int ifaupflags,
    struct in6_ifaddr **iar)
{
  struct in6_addrlifetime ia6_lt;
  struct in6_ifaddr *ia;
  struct ifaddr *ifa;
  struct ifaddr *xifa;
  struct in6_addrlifetime *lt;
  uint64_t timenow;
  int plen, error;

  /* Sanity check parameters and initialize locals */
  VERIFY(ifp != NULL && ifra != NULL && iar != NULL);
  ia = NULL;
  ifa = NULL;
  error = 0;

  /*
   * We always require users to specify a valid IPv6 address for
   * the corresponding operation.
   */
  if (ifra->ifra_addr.sin6_family != AF_INET6 ||
      ifra->ifra_addr.sin6_len != sizeof(struct sockaddr_in6)) {
    error = EAFNOSUPPORT;
    goto unwind;
  }

  /* Validate ifra_prefixmask.sin6_len is properly bounded. */
  if (ifra->ifra_prefixmask.sin6_len == 0 ||
      ifra->ifra_prefixmask.sin6_len > sizeof(struct sockaddr_in6)) {
    error = EINVAL;
    goto unwind;
  }

  /* Validate prefix length extracted from ifra_prefixmask structure. */
  plen = (uint8_t)in6_mask2len(&ifra->ifra_prefixmask.sin6_addr,
      (u_char *)&ifra->ifra_prefixmask + ifra->ifra_prefixmask.sin6_len);
  if (plen <= 0) {
    error = EINVAL;
    goto unwind;
  }

  /* Validate lifetimes */
  lt = &ifra->ifra_lifetime;
  if (lt->ia6t_pltime > lt->ia6t_vltime) {
    log(LOG_INFO,
        "%s: pltime 0x%x > vltime 0x%x for %s\n", __func__,
        lt->ia6t_pltime, lt->ia6t_vltime,
        ip6_sprintf(&ifra->ifra_addr.sin6_addr));
    error = EINVAL;
    goto unwind;
  }
  if (lt->ia6t_vltime == 0) {
    /*
     * the following log might be noisy, but this is a typical
     * configuration mistake or a tool's bug.
     */
    log(LOG_INFO, "%s: valid lifetime is 0 for %s\n", __func__,
        ip6_sprintf(&ifra->ifra_addr.sin6_addr));
  }

  /*
   * Before we lock the ifnet structure, we first check to see if the
   * address already exists. If so, then we don't allocate and link a
   * new one here.
   */
  struct sockaddr_in6 lookup_address = ifra->ifra_addr;
  if (IN6_IS_ADDR_LINKLOCAL(&lookup_address.sin6_addr)) {
    if (lookup_address.sin6_addr.s6_addr16[1] == 0) {
      /* link ID is not embedded by the user */
      lookup_address.sin6_addr.s6_addr16[1] =
          htons(ifp->if_index);
    } else if (lookup_address.sin6_addr.s6_addr16[1] !=
        htons(ifp->if_index)) {
      error = EINVAL; /* link ID contradicts */
      goto done;
    }
    if (lookup_address.sin6_scope_id != 0 &&
        lookup_address.sin6_scope_id !=
        (u_int32_t)ifp->if_index) {
      error = EINVAL;
      goto done;
    }
  }

  ia = in6ifa_ifpwithaddr(ifp, &lookup_address.sin6_addr);
  if (ia != NULL) {
    ifa = &ia->ia_ifa;
  }

  /*
   * Validate destination address on interface types that require it.
   */
  if ((ifp->if_flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) != 0) {
    switch (ifra->ifra_dstaddr.sin6_family) {
    case AF_INET6:
      if (plen != 128) {
        /* noisy message for diagnostic purposes */
        log(LOG_INFO,
            "%s: prefix length < 128 with"
            " explicit dstaddr.\n", __func__);
        error = EINVAL;
        goto unwind;
      }
      break;

    case AF_UNSPEC:
      break;

    default:
      error = EAFNOSUPPORT;
      goto unwind;
    }
  } else if (ifra->ifra_dstaddr.sin6_family != AF_UNSPEC) {
    log(LOG_INFO,
        "%s: dstaddr valid only on p2p and loopback interfaces.\n",
        __func__);
    error = EINVAL;
    goto unwind;
  }

  timenow = net_uptime();

  if (ia == NULL) {
    zalloc_flags_t how;

    /* Is this the first new IPv6 address for the interface? */
    ifaupflags |= IN6_IFAUPDATE_NEWADDR;

    /* Allocate memory for IPv6 interface address structure. */
    how = (ifaupflags & IN6_IFAUPDATE_NOWAIT) ? Z_NOWAIT : Z_WAITOK;
    ia = in6_ifaddr_alloc(how);
    if (ia == NULL) {
      error = ENOBUFS;
      goto unwind;
    }

    ifa = &ia->ia_ifa;

    /*
     * Initialize interface address structure.
     *
     * Note well: none of these sockaddr_in6 structures contain a
     * valid sin6_port, sin6_flowinfo or even a sin6_scope_id field.
     * We still embed link-local scope identifiers at the end of an
     * arbitrary fe80::/32 prefix, for historical reasons. Also, the
     * ifa_dstaddr field is always non-NULL on point-to-point and
     * loopback interfaces, and conventionally points to a socket
     * address of AF_UNSPEC family when there is no destination.
     *
     * Please enjoy the dancing sea turtle.
     */
    IFA_ADDREF(ifa); /* for this and optionally for caller */
    IA6_HASH_INIT(ia);
    ifa->ifa_addr = (struct sockaddr *)&ia->ia_addr;
    if (ifra->ifra_dstaddr.sin6_family == AF_INET6 ||
        (ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) != 0) {
      ifa->ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr;
    }
    ifa->ifa_netmask = (struct sockaddr *)&ia->ia_prefixmask;
    ifa->ifa_ifp = ifp;
    ifa->ifa_metric = ifp->if_metric;
    ifa->ifa_rtrequest = nd6_rtrequest;

    LIST_INIT(&ia->ia6_memberships);
    ia->ia_addr.sin6_family = AF_INET6;
    ia->ia_addr.sin6_len = sizeof(ia->ia_addr);
    ia->ia_addr.sin6_addr = ifra->ifra_addr.sin6_addr;
    ia->ia_prefixmask.sin6_family = AF_INET6;
    ia->ia_prefixmask.sin6_len = sizeof(ia->ia_prefixmask);
    ia->ia_prefixmask.sin6_addr = ifra->ifra_prefixmask.sin6_addr;
    error = in6_to_kamescope(&ia->ia_addr, ifp);
    if (error != 0) {
      goto unwind;
    }
    if (ifa->ifa_dstaddr != NULL) {
      ia->ia_dstaddr = ifra->ifra_dstaddr;
      error = in6_to_kamescope(&ia->ia_dstaddr, ifp);
      if (error != 0) {
        goto unwind;
      }
    }

    /* Append to address chains */
    ifnet_lock_exclusive(ifp);
    ifaupflags |= IN6_IFAUPDATE_1STADDR;
    TAILQ_FOREACH(xifa, &ifp->if_addrlist, ifa_list) {
      IFA_LOCK_SPIN(xifa);
      if (xifa->ifa_addr->sa_family != AF_INET6) {
        IFA_UNLOCK(xifa);
        ifaupflags &= ~IN6_IFAUPDATE_1STADDR;
        break;
      }
      IFA_UNLOCK(xifa);
    }

    IFA_LOCK_SPIN(ifa);
    if_attach_ifa(ifp, ifa); /* holds reference for ifnet link */
    IFA_UNLOCK(ifa);
    ifnet_lock_done(ifp);

    lck_rw_lock_exclusive(&in6_ifaddr_rwlock);
    TAILQ_INSERT_TAIL(&in6_ifaddrhead, ia, ia6_link);
    IFA_ADDREF(ifa); /* hold for in6_ifaddrs link */
    lck_rw_done(&in6_ifaddr_rwlock);
  } else {
    ifa = &ia->ia_ifa;
    ifaupflags &= ~(IN6_IFAUPDATE_NEWADDR | IN6_IFAUPDATE_1STADDR);
  }

  VERIFY(ia != NULL && ifa == &ia->ia_ifa);
  IFA_LOCK(ifa);

  /*
   * Set lifetimes.  We do not refer to ia6t_expire and ia6t_preferred
   * to see if the address is deprecated or invalidated, but initialize
   * these members for applications.
   */
  ia->ia6_updatetime = ia->ia6_createtime = timenow;
  ia6_lt = *lt;
  if (ia6_lt.ia6t_vltime != ND6_INFINITE_LIFETIME) {
    ia6_lt.ia6t_expire = timenow + ia6_lt.ia6t_vltime;
  } else {
    ia6_lt.ia6t_expire = 0;
  }
  if (ia6_lt.ia6t_pltime != ND6_INFINITE_LIFETIME) {
    ia6_lt.ia6t_preferred = timenow + ia6_lt.ia6t_pltime;
  } else {
    ia6_lt.ia6t_preferred = 0;
  }
  in6ifa_setlifetime(ia, &ia6_lt);

  /*
   * Backward compatibility - if IN6_IFF_DEPRECATED is set from the
   * userland, make it deprecated.
   */
  if ((ia->ia6_flags & IN6_IFF_DEPRECATED) != 0) {
    ia->ia6_lifetime.ia6ti_pltime = 0;
    ia->ia6_lifetime.ia6ti_preferred = timenow;
  }

  /*
   * Update flag or prefix length
   */
  ia->ia_plen = plen;
  ia->ia6_flags = ifra->ifra_flags;

  /* Release locks (new address available to concurrent tasks) */
  IFA_UNLOCK(ifa);

  /* Further initialization of the interface address */
  error = in6_ifinit(ifp, ia, ifaupflags);
  if (error != 0) {
    goto unwind;
  }

  /* Finish updating the address while other tasks are working with it */
  error = in6_ifaupdate_aux(ia, ifp, ifaupflags);
  if (error != 0) {
    goto unwind;
  }

  /* Return success (optionally w/ address for caller). */
  VERIFY(error == 0);
  (void) ifnet_notify_address(ifp, AF_INET6);
  goto done;

unwind:
  VERIFY(error != 0);
  if (ia != NULL) {
    VERIFY(ifa == &ia->ia_ifa);
    IFA_REMREF(ifa);
    ia = NULL;
  }

done:
  *iar = ia;
  return error;
}

void
in6_purgeaddr(struct ifaddr *ifa)
{
  struct ifnet *ifp = ifa->ifa_ifp;
  struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
  struct in6_multi_mship *imm;

  LCK_MTX_ASSERT(nd6_mutex, LCK_MTX_ASSERT_NOTOWNED);

  /* stop DAD processing */
  nd6_dad_stop(ifa);

  /*
   * delete route to the destination of the address being purged.
   * The interface must be p2p or loopback in this case.
   */
  IFA_LOCK(ifa);
  if ((ia->ia_flags & IFA_ROUTE) && ia->ia_plen == 128) {
    int error, rtf;

    IFA_UNLOCK(ifa);
    rtf = (ia->ia_dstaddr.sin6_family == AF_INET6) ? RTF_HOST : 0;
    error = rtinit(&(ia->ia_ifa), RTM_DELETE, rtf);
    if (error != 0) {
      log(LOG_ERR, "in6_purgeaddr: failed to remove "
          "a route to the p2p destination: %s on %s, "
          "errno=%d\n",
          ip6_sprintf(&ia->ia_addr.sin6_addr), if_name(ifp),
          error);
      /* proceed anyway... */
    }
    IFA_LOCK_SPIN(ifa);
    ia->ia_flags &= ~IFA_ROUTE;
  }
  IFA_UNLOCK(ifa);

  /* Remove ownaddr's loopback rtentry, if it exists. */
  in6_ifremloop(&(ia->ia_ifa));

  /*
   * leave from multicast groups we have joined for the interface
   */
  IFA_LOCK(ifa);
  while ((imm = ia->ia6_memberships.lh_first) != NULL) {
    LIST_REMOVE(imm, i6mm_chain);
    IFA_UNLOCK(ifa);
    in6_leavegroup(imm);
    IFA_LOCK(ifa);
  }
  IFA_UNLOCK(ifa);

  /* in6_unlink_ifa() will need exclusive access */
  in6_unlink_ifa(ia, ifp);
  in6_post_msg(ifp, KEV_INET6_ADDR_DELETED, ia, NULL);

  (void) ifnet_notify_address(ifp, AF_INET6);
}

static void
in6_unlink_ifa(struct in6_ifaddr *ia, struct ifnet *ifp)
{
  struct in6_ifaddr *nia;
  struct ifaddr *ifa;
  int unlinked;

  LCK_MTX_ASSERT(nd6_mutex, LCK_MTX_ASSERT_NOTOWNED);

  ifa = &ia->ia_ifa;
  IFA_ADDREF(ifa);

  ifnet_lock_exclusive(ifp);
  IFA_LOCK(ifa);
  if (ifa->ifa_debug & IFD_ATTACHED) {
    if_detach_ifa(ifp, ifa);
  }
  IFA_UNLOCK(ifa);
  ifnet_lock_done(ifp);

  unlinked = 0;
  lck_rw_lock_exclusive(&in6_ifaddr_rwlock);
  TAILQ_FOREACH(nia, &in6_ifaddrhead, ia6_link) {
    if (ia == nia) {
      TAILQ_REMOVE(&in6_ifaddrhead, ia, ia6_link);
      IFA_LOCK(ifa);
      if (IA6_IS_HASHED(ia)) {
        in6_iahash_remove(ia);
      }
      IFA_UNLOCK(ifa);
      unlinked = 1;
      break;
    }
  }

  /*
   * When IPv6 address is being removed, release the
   * reference to the base prefix.
   * Also, since the release might, affect the status
   * of other (detached) addresses, call
   * pfxlist_onlink_check().
   */
  IFA_LOCK(ifa);
  /*
   * Only log the below message for addresses other than
   * link local.
   * Only one LLA (auto-configured or statically) is allowed
   * on an interface.
   * LLA prefix, while added to the prefix list, is not
   * reference countedi (as it is the only one).
   * The prefix also never expires on its own as LLAs
   * have infinite lifetime.
   *
   * For now quiece down the log message for LLAs.
   */
  if (!IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) {
    if (ia->ia6_ndpr == NULL) {
      log(LOG_NOTICE, "in6_unlink_ifa: IPv6 address "
          "0x%llx has no prefix\n",
          (uint64_t)VM_KERNEL_ADDRPERM(ia));
    } else {
      struct nd_prefix *pr = ia->ia6_ndpr;
      ia->ia6_flags &= ~IN6_IFF_AUTOCONF;
      ia->ia6_ndpr = NULL;
      NDPR_LOCK(pr);
      VERIFY(pr->ndpr_addrcnt != 0);
      pr->ndpr_addrcnt--;
      if (ia->ia6_flags & IN6_IFF_CLAT46) {
        pr->ndpr_stateflags &= ~NDPRF_CLAT46;
      }
      NDPR_UNLOCK(pr);
      NDPR_REMREF(pr);        /* release addr reference */
    }
  }
  IFA_UNLOCK(ifa);
  lck_rw_done(&in6_ifaddr_rwlock);

  if ((ia->ia6_flags & IN6_IFF_AUTOCONF) != 0) {
    lck_mtx_lock(nd6_mutex);
    pfxlist_onlink_check();
    lck_mtx_unlock(nd6_mutex);
  }
  /*
   * release another refcnt for the link from in6_ifaddrs.
   * Do this only if it's not already unlinked in the event that we lost
   * the race, since in6_ifaddr_rwlock was momentarily dropped above.
   */
  if (unlinked) {
    IFA_REMREF(ifa);
  }

  /* release reference held for this routine */
  IFA_REMREF(ifa);

  /* invalidate route caches */
  routegenid_inet6_update();
}

void
in6_purgeif(struct ifnet *ifp)
{
  struct in6_ifaddr *ia;

  if (ifp == NULL) {
    return;
  }

  LCK_MTX_ASSERT(nd6_mutex, LCK_MTX_ASSERT_NOTOWNED);

  lck_rw_lock_exclusive(&in6_ifaddr_rwlock);
  boolean_t from_begining = TRUE;
  while (from_begining) {
    from_begining = FALSE;
    TAILQ_FOREACH(ia, &in6_ifaddrhead, ia6_link) {
      if (ia->ia_ifa.ifa_ifp != ifp) {
        continue;
      }
      IFA_ADDREF(&ia->ia_ifa);        /* for us */
      lck_rw_done(&in6_ifaddr_rwlock);
      in6_purgeaddr(&ia->ia_ifa);
      IFA_REMREF(&ia->ia_ifa);        /* for us */
      lck_rw_lock_exclusive(&in6_ifaddr_rwlock);
      /*
       * Purging the address would have caused
       * in6_ifaddr_rwlock to be dropped and reacquired;
       * therefore search again from the beginning
       * of in6_ifaddrs list.
       */
      from_begining = TRUE;
      break;
    }
  }
  lck_rw_done(&in6_ifaddr_rwlock);

  in6_ifdetach(ifp);
}

/*
 * Initialize an interface's internet6 address and routing table entry.
 */
static int
in6_ifinit(struct ifnet *ifp, struct in6_ifaddr *ia, int ifaupflags)
{
  int error;
  struct ifaddr *ifa;

  error = 0;
  ifa = &ia->ia_ifa;

  lck_rw_lock_exclusive(&in6_ifaddr_rwlock);
  IFA_LOCK(&ia->ia_ifa);
  if (IA6_IS_HASHED(ia)) {
    in6_iahash_remove(ia);
  }
  if ((ifp->if_flags & IFF_POINTOPOINT)) {
    in6_iahash_insert_ptp(ia);
  } else {
    in6_iahash_insert(ia);
  }
  IFA_UNLOCK(&ia->ia_ifa);
  lck_rw_done(&in6_ifaddr_rwlock);

  /*
   * NOTE: SIOCSIFADDR is defined with struct ifreq as parameter,
   * but here we are sending it down to the interface with a pointer
   * to struct ifaddr, for legacy reasons.
   */
  if ((ifaupflags & IN6_IFAUPDATE_1STADDR) != 0) {
    error = ifnet_ioctl(ifp, PF_INET6, SIOCSIFADDR, ia);
    if (error != 0) {
      if (error != EOPNOTSUPP) {
        goto failed;
      }
      error = 0;
    }
  }

  IFA_LOCK(ifa);

  /*
   * Special case:
   * If the destination address is specified for a point-to-point
   * interface, install a route to the destination as an interface
   * direct route.
   */
  if (!(ia->ia_flags & IFA_ROUTE) && ia->ia_plen == 128 &&
      ia->ia_dstaddr.sin6_family == AF_INET6) {
    IFA_UNLOCK(ifa);
    error = rtinit(ifa, RTM_ADD, RTF_UP | RTF_HOST);
    if (error != 0) {
      goto failed;
    }
    IFA_LOCK(ifa);
    ia->ia_flags |= IFA_ROUTE;
  }
  IFA_LOCK_ASSERT_HELD(ifa);
  if (ia->ia_plen < 128) {
    /*
     * The RTF_CLONING flag is necessary for in6_is_ifloop_auto().
     */
    ia->ia_flags |= RTF_CLONING;
  }

  IFA_UNLOCK(ifa);

  /* Add ownaddr as loopback rtentry, if necessary (ex. on p2p link). */
  if ((ifaupflags & IN6_IFAUPDATE_NEWADDR) != 0) {
    in6_ifaddloop(ifa);
  }

  /* invalidate route caches */
  routegenid_inet6_update();

  VERIFY(error == 0);
  return 0;
failed:
  VERIFY(error != 0);
  lck_rw_lock_exclusive(&in6_ifaddr_rwlock);
  IFA_LOCK(&ia->ia_ifa);
  if (IA6_IS_HASHED(ia)) {
    in6_iahash_remove(ia);
  }
  IFA_UNLOCK(&ia->ia_ifa);
  lck_rw_done(&in6_ifaddr_rwlock);

  return error;
}

void
in6_purgeaddrs(struct ifnet *ifp)
{
  in6_purgeif(ifp);
}

/*
 * Find an IPv6 interface link-local address specific to an interface.
 */
struct in6_ifaddr *
in6ifa_ifpforlinklocal(struct ifnet *ifp, int ignoreflags)
{
  struct ifaddr *ifa;

  ifnet_lock_shared(ifp);
  TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
  {
    IFA_LOCK_SPIN(ifa);
    if (ifa->ifa_addr->sa_family != AF_INET6) {
      IFA_UNLOCK(ifa);
      continue;
    }
    if (IN6_IS_ADDR_LINKLOCAL(IFA_IN6(ifa))) {
      if ((((struct in6_ifaddr *)ifa)->ia6_flags &
          ignoreflags) != 0) {
        IFA_UNLOCK(ifa);
        continue;
      }
      IFA_ADDREF_LOCKED(ifa); /* for caller */
      IFA_UNLOCK(ifa);
      break;
    }
    IFA_UNLOCK(ifa);
  }
  ifnet_lock_done(ifp);

  return (struct in6_ifaddr *)ifa;
}

struct in6_ifaddr *
in6ifa_ifpwithflag(struct ifnet * ifp, int flag)
{
  struct ifaddr *ifa;

  ifnet_lock_shared(ifp);
  TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
  {
    IFA_LOCK_SPIN(ifa);
    if (ifa->ifa_addr->sa_family != AF_INET6) {
      IFA_UNLOCK(ifa);
      continue;
    }
    if ((((struct in6_ifaddr *)ifa)->ia6_flags & flag) == flag) {
      IFA_ADDREF_LOCKED(ifa);
      IFA_UNLOCK(ifa);
      break;
    }
    IFA_UNLOCK(ifa);
  }
  ifnet_lock_done(ifp);

  return (struct in6_ifaddr *)ifa;
}

/*
 * find the internet address corresponding to a given interface and address.
 */
struct in6_ifaddr *
in6ifa_ifpwithaddr(struct ifnet *ifp, struct in6_addr *addr)
{
  struct ifaddr *ifa;

  ifnet_lock_shared(ifp);
  TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
  {
    IFA_LOCK_SPIN(ifa);
    if (ifa->ifa_addr->sa_family != AF_INET6) {
      IFA_UNLOCK(ifa);
      continue;
    }
    if (IN6_ARE_ADDR_EQUAL(addr, IFA_IN6(ifa))) {
      IFA_ADDREF_LOCKED(ifa); /* for caller */
      IFA_UNLOCK(ifa);
      break;
    }
    IFA_UNLOCK(ifa);
  }
  ifnet_lock_done(ifp);

  return (struct in6_ifaddr *)ifa;
}

struct in6_ifaddr *
in6ifa_prproxyaddr(struct in6_addr *addr)
{
  struct in6_ifaddr *ia;

  lck_rw_lock_shared(&in6_ifaddr_rwlock);
  TAILQ_FOREACH(ia, IN6ADDR_HASH(addr), ia6_hash) {
    IFA_LOCK(&ia->ia_ifa);
    if (IN6_ARE_ADDR_EQUAL(addr, IFA_IN6(&ia->ia_ifa))) {
      IFA_ADDREF_LOCKED(&ia->ia_ifa); /* for caller */
      IFA_UNLOCK(&ia->ia_ifa);
      break;
    }
    IFA_UNLOCK(&ia->ia_ifa);
  }
  lck_rw_done(&in6_ifaddr_rwlock);

  if (ia != NULL && !nd6_prproxy_ifaddr(ia)) {
    IFA_REMREF(&ia->ia_ifa);
    ia = NULL;
  }

  return ia;
}

void
in6ifa_getlifetime(struct in6_ifaddr *ia6, struct in6_addrlifetime *t_dst,
    int iscalendar)
{
  struct in6_addrlifetime_i *t_src = &ia6->ia6_lifetime;
  struct timeval caltime;

  t_dst->ia6t_vltime = t_src->ia6ti_vltime;
  t_dst->ia6t_pltime = t_src->ia6ti_pltime;
  t_dst->ia6t_expire = 0;
  t_dst->ia6t_preferred = 0;

  /* account for system time change */
  getmicrotime(&caltime);
  t_src->ia6ti_base_calendartime +=
      NET_CALCULATE_CLOCKSKEW(caltime,
      t_src->ia6ti_base_calendartime, net_uptime(),
      t_src->ia6ti_base_uptime);

  if (iscalendar) {
    if (t_src->ia6ti_expire != 0 &&
        t_src->ia6ti_vltime != ND6_INFINITE_LIFETIME) {
      t_dst->ia6t_expire = t_src->ia6ti_base_calendartime +
          t_src->ia6ti_expire - t_src->ia6ti_base_uptime;
    }

    if (t_src->ia6ti_preferred != 0 &&
        t_src->ia6ti_pltime != ND6_INFINITE_LIFETIME) {
      t_dst->ia6t_preferred = t_src->ia6ti_base_calendartime +
          t_src->ia6ti_preferred - t_src->ia6ti_base_uptime;
    }
  } else {
    if (t_src->ia6ti_expire != 0 &&
        t_src->ia6ti_vltime != ND6_INFINITE_LIFETIME) {
      t_dst->ia6t_expire = t_src->ia6ti_expire;
    }

    if (t_src->ia6ti_preferred != 0 &&
        t_src->ia6ti_pltime != ND6_INFINITE_LIFETIME) {
      t_dst->ia6t_preferred = t_src->ia6ti_preferred;
    }
  }
}

void
in6ifa_setlifetime(struct in6_ifaddr *ia6, struct in6_addrlifetime *t_src)
{
  struct in6_addrlifetime_i *t_dst = &ia6->ia6_lifetime;
  struct timeval caltime;

  /* account for system time change */
  getmicrotime(&caltime);
  t_dst->ia6ti_base_calendartime +=
      NET_CALCULATE_CLOCKSKEW(caltime,
      t_dst->ia6ti_base_calendartime, net_uptime(),
      t_dst->ia6ti_base_uptime);

  /* trust the caller for the values */
  t_dst->ia6ti_expire = t_src->ia6t_expire;
  t_dst->ia6ti_preferred = t_src->ia6t_preferred;
  t_dst->ia6ti_vltime = t_src->ia6t_vltime;
  t_dst->ia6ti_pltime = t_src->ia6t_pltime;
}

/*
 * Convert IP6 address to printable (loggable) representation.
 */
char *
ip6_sprintf(const struct in6_addr *addr)
{
  static const char digits[] = "0123456789abcdef";
  static int ip6round = 0;
  static char ip6buf[8][48];

  int i;
  char *cp;
  const u_short *a = (const u_short *)addr;
  const u_char *d;
  u_char n;
  int dcolon = 0;
  int zpad = 0;

  ip6round = (ip6round + 1) & 7;
  cp = ip6buf[ip6round];

  for (i = 0; i < 8; i++) {
    if (dcolon == 1) {
      if (*a == 0) {
        if (i == 7) {
          *cp++ = ':';
        }
        a++;
        continue;
      } else {
        dcolon = 2;
      }
    }
    if (*a == 0) {
      if (dcolon == 0 && *(a + 1) == 0) {
        if (i == 0) {
          *cp++ = ':';
        }
        *cp++ = ':';
        dcolon = 1;
      } else {
        *cp++ = '0';
        *cp++ = ':';
      }
      a++;
      continue;
    }
    d = (const u_char *)a;
    zpad = 0;
    if ((n = *d >> 4) != 0) {
      *cp++ = digits[n];
      zpad = 1;
    }
    if ((n = *d++ & 0xf) != 0 || zpad) {
      *cp++ = digits[n];
      zpad = 1;
    }
    if ((n = *d >> 4) != 0 || zpad) {
      *cp++ = digits[n];
      zpad = 1;
    }
    if ((n = *d & 0xf) != 0 || zpad) {
      *cp++ = digits[n];
    }
    *cp++ = ':';
    a++;
  }
  *--cp = 0;
  return ip6buf[ip6round];
}

int
in6addr_local(struct in6_addr *in6)
{
  struct rtentry *rt;
  struct sockaddr_in6 sin6;
  int local = 0;

  if (IN6_IS_ADDR_LOOPBACK(in6) || IN6_IS_SCOPE_LINKLOCAL(in6)) {
    return 1;
  }

  sin6.sin6_family = AF_INET6;
  sin6.sin6_len = sizeof(sin6);
  bcopy(in6, &sin6.sin6_addr, sizeof(*in6));
  rt = rtalloc1((struct sockaddr *)&sin6, 0, 0);

  if (rt != NULL) {
    RT_LOCK_SPIN(rt);
    if (rt->rt_gateway->sa_family == AF_LINK) {
      local = 1;
    }
    RT_UNLOCK(rt);
    rtfree(rt);
  } else {
    local = in6_localaddr(in6);
  }
  return local;
}

int
in6_localaddr(struct in6_addr *in6)
{
  struct in6_ifaddr *ia;

  if (IN6_IS_ADDR_LOOPBACK(in6) || IN6_IS_ADDR_LINKLOCAL(in6) || IN6_IS_ADDR_MC_UNICAST_BASED_LINKLOCAL(in6)) {
    return 1;
  }

  lck_rw_lock_shared(&in6_ifaddr_rwlock);
  TAILQ_FOREACH(ia, &in6_ifaddrhead, ia6_link) {
    IFA_LOCK_SPIN(&ia->ia_ifa);
    if (IN6_ARE_MASKED_ADDR_EQUAL(in6, &ia->ia_addr.sin6_addr,
        &ia->ia_prefixmask.sin6_addr)) {
      IFA_UNLOCK(&ia->ia_ifa);
      lck_rw_done(&in6_ifaddr_rwlock);
      return 1;
    }
    IFA_UNLOCK(&ia->ia_ifa);
  }
  lck_rw_done(&in6_ifaddr_rwlock);
  return 0;
}

/*
 * return length of part which dst and src are equal
 * hard coding...
 */
int
in6_matchlen(struct in6_addr *src, struct in6_addr *dst)
{
  int match = 0;
  u_char *s = (u_char *)src, *d = (u_char *)dst;
  u_char *lim = s + 16, r;

  while (s < lim) {
    if ((r = (*d++ ^ *s++)) != 0) {
      while (r < 128) {
        match++;
        r <<= 1;
      }
      break;
    } else {
      match += 8;
    }
  }
  return match;
}

/* XXX: to be scope conscious */
int
in6_are_prefix_equal(struct in6_addr *p1, struct in6_addr *p2, int len)
{
  int bytelen, bitlen;

  /* sanity check */
  if (0 > len || len > 128) {
    log(LOG_ERR, "%s: invalid prefix length(%d)\n", __func__, len);
    return 0;
  }

  bytelen = len / 8;
  bitlen = len % 8;

  if (bcmp(&p1->s6_addr, &p2->s6_addr, bytelen)) {
    return 0;
  }
  if (bitlen != 0 &&
      p1->s6_addr[bytelen] >> (8 - bitlen) !=
      p2->s6_addr[bytelen] >> (8 - bitlen)) {
    return 0;
  }

  return 1;
}

void
in6_prefixlen2mask(struct in6_addr *maskp, int len)
{
  u_char maskarray[8] = {0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, 0xff};
  int bytelen, bitlen, i;

  /* sanity check */
  if (0 > len || len > 128) {
    log(LOG_ERR, "%s: invalid prefix length(%d)\n", __func__, len);
    return;
  }

  bzero(maskp, sizeof(*maskp));
  bytelen = len / 8;
  bitlen = len % 8;
  for (i = 0; i < bytelen; i++) {
    maskp->s6_addr[i] = 0xff;
  }
  if (bitlen) {
    maskp->s6_addr[bytelen] = maskarray[bitlen - 1];
  }
}

/*
 * return the best address out of the same scope
 */
struct in6_ifaddr *
in6_ifawithscope(struct ifnet *oifp, struct in6_addr *dst)
{
  int dst_scope = in6_addrscope(dst), src_scope, best_scope = 0;
  int blen = -1;
  struct ifaddr *ifa;
  struct ifnet *ifp;
  struct in6_ifaddr *ifa_best = NULL;

  if (oifp == NULL) {
    return NULL;
  }

  /*
   * We search for all addresses on all interfaces from the beginning.
   * Comparing an interface with the outgoing interface will be done
   * only at the final stage of tiebreaking.
   */
  ifnet_head_lock_shared();
  TAILQ_FOREACH(ifp, &ifnet_head, if_list) {
    /*
     * We can never take an address that breaks the scope zone
     * of the destination.
     */
    if (in6_addr2scopeid(ifp, dst) != in6_addr2scopeid(oifp, dst)) {
      continue;
    }

    ifnet_lock_shared(ifp);
    TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) {
      int tlen = -1, dscopecmp, bscopecmp, matchcmp;

      IFA_LOCK(ifa);
      if (ifa->ifa_addr->sa_family != AF_INET6) {
        IFA_UNLOCK(ifa);
        continue;
      }
      src_scope = in6_addrscope(IFA_IN6(ifa));

      /*
       * Don't use an address before completing DAD
       * nor a duplicated address.
       */
      if (((struct in6_ifaddr *)ifa)->ia6_flags &
          (IN6_IFF_NOTREADY | IN6_IFF_CLAT46)) {
        IFA_UNLOCK(ifa);
        continue;
      }
      /* XXX: is there any case to allow anycasts? */
      if (((struct in6_ifaddr *)ifa)->ia6_flags &
          IN6_IFF_ANYCAST) {
        IFA_UNLOCK(ifa);
        continue;
      }
      if (((struct in6_ifaddr *)ifa)->ia6_flags &
          IN6_IFF_DETACHED) {
        IFA_UNLOCK(ifa);
        continue;
      }
      /*
       * If this is the first address we find,
       * keep it anyway.
       */
      if (ifa_best == NULL) {
        goto replace;
      }

      /*
       * ifa_best is never NULL beyond this line except
       * within the block labeled "replace".
       */

      /*
       * If ifa_best has a smaller scope than dst and
       * the current address has a larger one than
       * (or equal to) dst, always replace ifa_best.
       * Also, if the current address has a smaller scope
       * than dst, ignore it unless ifa_best also has a
       * smaller scope.
       * Consequently, after the two if-clause below,
       * the followings must be satisfied:
       * (scope(src) < scope(dst) &&
       *  scope(best) < scope(dst))
       *  OR
       * (scope(best) >= scope(dst) &&
       *  scope(src) >= scope(dst))
       */
      if (IN6_ARE_SCOPE_CMP(best_scope, dst_scope) < 0 &&
          IN6_ARE_SCOPE_CMP(src_scope, dst_scope) >= 0) {
        goto replace; /* (A) */
      }
      if (IN6_ARE_SCOPE_CMP(src_scope, dst_scope) < 0 &&
          IN6_ARE_SCOPE_CMP(best_scope, dst_scope) >= 0) {
        IFA_UNLOCK(ifa);
        continue; /* (B) */
      }
      /*
       * A deprecated address SHOULD NOT be used in new
       * communications if an alternate (non-deprecated)
       * address is available and has sufficient scope.
       * RFC 4862, Section 5.5.4.
       */
      if (((struct in6_ifaddr *)ifa)->ia6_flags &
          IN6_IFF_DEPRECATED) {
        /*
         * Ignore any deprecated addresses if
         * specified by configuration.
         */
        if (!ip6_use_deprecated) {
          IFA_UNLOCK(ifa);
          continue;
        }
        /*
         * If we have already found a non-deprecated
         * candidate, just ignore deprecated addresses.
         */
        if ((ifa_best->ia6_flags & IN6_IFF_DEPRECATED)
            == 0) {
          IFA_UNLOCK(ifa);
          continue;
        }
      }

      /*
       * A non-deprecated address is always preferred
       * to a deprecated one regardless of scopes and
       * address matching (Note invariants ensured by the
       * conditions (A) and (B) above.)
       */
      if ((ifa_best->ia6_flags & IN6_IFF_DEPRECATED) &&
          (((struct in6_ifaddr *)ifa)->ia6_flags &
          IN6_IFF_DEPRECATED) == 0) {
        goto replace;
      }

      /*
       * When we use temporary addresses described in
       * RFC 4941, we prefer temporary addresses to
       * public autoconf addresses.  Again, note the
       * invariants from (A) and (B).  Also note that we
       * don't have any preference between static addresses
       * and autoconf addresses (despite of whether or not
       * the latter is temporary or public.)
       */
      if (ip6_use_tempaddr) {
        struct in6_ifaddr *ifat;

        ifat = (struct in6_ifaddr *)ifa;
        if ((ifa_best->ia6_flags &
            (IN6_IFF_AUTOCONF | IN6_IFF_TEMPORARY))
            == IN6_IFF_AUTOCONF &&
            (ifat->ia6_flags &
            (IN6_IFF_AUTOCONF | IN6_IFF_TEMPORARY))
            == (IN6_IFF_AUTOCONF | IN6_IFF_TEMPORARY)) {
          goto replace;
        }
        if ((ifa_best->ia6_flags &
            (IN6_IFF_AUTOCONF | IN6_IFF_TEMPORARY))
            == (IN6_IFF_AUTOCONF | IN6_IFF_TEMPORARY) &&
            (ifat->ia6_flags &
            (IN6_IFF_AUTOCONF | IN6_IFF_TEMPORARY))
            == IN6_IFF_AUTOCONF) {
          IFA_UNLOCK(ifa);
          continue;
        }
      }

      /*
       * At this point, we have two cases:
       * 1. we are looking at a non-deprecated address,
       *    and ifa_best is also non-deprecated.
       * 2. we are looking at a deprecated address,
       *    and ifa_best is also deprecated.
       * Also, we do not have to consider a case where
       * the scope of if_best is larger(smaller) than dst and
       * the scope of the current address is smaller(larger)
       * than dst. Such a case has already been covered.
       * Tiebreaking is done according to the following
       * items:
       * - the scope comparison between the address and
       *   dst (dscopecmp)
       * - the scope comparison between the address and
       *   ifa_best (bscopecmp)
       * - if the address match dst longer than ifa_best
       *   (matchcmp)
       * - if the address is on the outgoing I/F (outI/F)
       *
       * Roughly speaking, the selection policy is
       * - the most important item is scope. The same scope
       *   is best. Then search for a larger scope.
       *   Smaller scopes are the last resort.
       * - A deprecated address is chosen only when we have
       *   no address that has an enough scope, but is
       *   prefered to any addresses of smaller scopes
       *   (this must be already done above.)
       * - addresses on the outgoing I/F are preferred to
       *   ones on other interfaces if none of above
       *   tiebreaks.  In the table below, the column "bI"
       *   means if the best_ifa is on the outgoing
       *   interface, and the column "sI" means if the ifa
       *   is on the outgoing interface.
       * - If there is no other reasons to choose one,
       *   longest address match against dst is considered.
       *
       * The precise decision table is as follows:
       * dscopecmp bscopecmp  match   bI oI | replace?
       *   N/A       equal    N/A     Y   N |   No (1)
       *   N/A       equal    N/A     N   Y |  Yes (2)
       *   N/A       equal    larger   N/A  |  Yes (3)
       *   N/A       equal    !larger  N/A  |   No (4)
       *   larger    larger   N/A      N/A  |   No (5)
       *   larger    smaller  N/A      N/A  |  Yes (6)
       *   smaller   larger   N/A      N/A  |  Yes (7)
       *   smaller   smaller  N/A      N/A  |   No (8)
       *   equal     smaller  N/A      N/A  |  Yes (9)
       *   equal     larger   (already done at A above)
       */
      dscopecmp = IN6_ARE_SCOPE_CMP(src_scope, dst_scope);
      bscopecmp = IN6_ARE_SCOPE_CMP(src_scope, best_scope);

      if (bscopecmp == 0) {
        struct ifnet *bifp = ifa_best->ia_ifp;

        if (bifp == oifp && ifp != oifp) { /* (1) */
          IFA_UNLOCK(ifa);
          continue;
        }
        if (bifp != oifp && ifp == oifp) { /* (2) */
          goto replace;
        }

        /*
         * Both bifp and ifp are on the outgoing
         * interface, or both two are on a different
         * interface from the outgoing I/F.
         * now we need address matching against dst
         * for tiebreaking.
         */
        tlen = in6_matchlen(IFA_IN6(ifa), dst);
        matchcmp = tlen - blen;
        if (matchcmp > 0) { /* (3) */
          goto replace;
        }
        IFA_UNLOCK(ifa);
        continue; /* (4) */
      }
      if (dscopecmp > 0) {
        if (bscopecmp > 0) { /* (5) */
          IFA_UNLOCK(ifa);
          continue;
        }
        goto replace; /* (6) */
      }
      if (dscopecmp < 0) {
        if (bscopecmp > 0) { /* (7) */
          goto replace;
        }
        IFA_UNLOCK(ifa);
        continue; /* (8) */
      }

      /* now dscopecmp must be 0 */
      if (bscopecmp < 0) {
        goto replace; /* (9) */
      }
replace:
      IFA_ADDREF_LOCKED(ifa); /* for ifa_best */
      blen = tlen >= 0 ? tlen :
          in6_matchlen(IFA_IN6(ifa), dst);
      best_scope =
          in6_addrscope(&ifa2ia6(ifa)->ia_addr.sin6_addr);
      IFA_UNLOCK(ifa);
      if (ifa_best) {
        IFA_REMREF(&ifa_best->ia_ifa);
      }
      ifa_best = (struct in6_ifaddr *)ifa;
    }
    ifnet_lock_done(ifp);
  }
  ifnet_head_done();

  /* count statistics for future improvements */
  if (ifa_best == NULL) {
    ip6stat.ip6s_sources_none++;
  } else {
    IFA_LOCK_SPIN(&ifa_best->ia_ifa);
    if (oifp == ifa_best->ia_ifp) {
      ip6stat.ip6s_sources_sameif[best_scope]++;
    } else {
      ip6stat.ip6s_sources_otherif[best_scope]++;
    }

    if (best_scope == dst_scope) {
      ip6stat.ip6s_sources_samescope[best_scope]++;
    } else {
      ip6stat.ip6s_sources_otherscope[best_scope]++;
    }

    if ((ifa_best->ia6_flags & IN6_IFF_DEPRECATED) != 0) {
      ip6stat.ip6s_sources_deprecated[best_scope]++;
    }
    IFA_UNLOCK(&ifa_best->ia_ifa);
  }

  return ifa_best;
}

/*
 * return the best address out of the same scope. if no address was
 * found, return the first valid address from designated IF.
 */
struct in6_ifaddr *
in6_ifawithifp(struct ifnet *ifp, struct in6_addr *dst)
{
  int dst_scope = in6_addrscope(dst), blen = -1, tlen;
  struct ifaddr *ifa;
  struct in6_ifaddr *besta = NULL;
  struct in6_ifaddr *dep[2];      /* last-resort: deprecated */

  dep[0] = dep[1] = NULL;

  /*
   * We first look for addresses in the same scope.
   * If there is one, return it.
   * If two or more, return one which matches the dst longest.
   * If none, return one of global addresses assigned other ifs.
   */
  ifnet_lock_shared(ifp);
  TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) {
    IFA_LOCK(ifa);
    if (ifa->ifa_addr->sa_family != AF_INET6) {
      IFA_UNLOCK(ifa);
      continue;
    }
    if (ifa2ia6(ifa)->ia6_flags & IN6_IFF_ANYCAST) {
      IFA_UNLOCK(ifa);
      continue; /* XXX: is there any case to allow anycast? */
    }
    if (ifa2ia6(ifa)->ia6_flags & (IN6_IFF_NOTREADY | IN6_IFF_CLAT46)) {
      IFA_UNLOCK(ifa);
      continue; /* don't use this interface */
    }
    if (ifa2ia6(ifa)->ia6_flags & IN6_IFF_DETACHED) {
      IFA_UNLOCK(ifa);
      continue;
    }
    if (ifa2ia6(ifa)->ia6_flags & IN6_IFF_DEPRECATED) {
      if (ip6_use_deprecated) {
        IFA_ADDREF_LOCKED(ifa); /* for dep[0] */
        IFA_UNLOCK(ifa);
        if (dep[0] != NULL) {
          IFA_REMREF(&dep[0]->ia_ifa);
        }
        dep[0] = (struct in6_ifaddr *)ifa;
      } else {
        IFA_UNLOCK(ifa);
      }
      continue;
    }

    if (dst_scope == in6_addrscope(IFA_IN6(ifa))) {
      /*
       * call in6_matchlen() as few as possible
       */
      if (besta) {
        if (blen == -1) {
          IFA_UNLOCK(ifa);
          IFA_LOCK(&besta->ia_ifa);
          blen = in6_matchlen(
            &besta->ia_addr.sin6_addr, dst);
          IFA_UNLOCK(&besta->ia_ifa);
          IFA_LOCK(ifa);
        }
        tlen = in6_matchlen(IFA_IN6(ifa), dst);
        if (tlen > blen) {
          blen = tlen;
          IFA_ADDREF_LOCKED(ifa); /* for besta */
          IFA_UNLOCK(ifa);
          IFA_REMREF(&besta->ia_ifa);
          besta = (struct in6_ifaddr *)ifa;
        } else {
          IFA_UNLOCK(ifa);
        }
      } else {
        besta = (struct in6_ifaddr *)ifa;
        IFA_ADDREF_LOCKED(ifa); /* for besta */
        IFA_UNLOCK(ifa);
      }
    } else {
      IFA_UNLOCK(ifa);
    }
  }
  if (besta) {
    ifnet_lock_done(ifp);
    if (dep[0] != NULL) {
      IFA_REMREF(&dep[0]->ia_ifa);
    }
    return besta;
  }

  TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) {
    IFA_LOCK(ifa);
    if (ifa->ifa_addr->sa_family != AF_INET6) {
      IFA_UNLOCK(ifa);
      continue;
    }
    if (ifa2ia6(ifa)->ia6_flags & IN6_IFF_ANYCAST) {
      IFA_UNLOCK(ifa);
      continue; /* XXX: is there any case to allow anycast? */
    }
    if (ifa2ia6(ifa)->ia6_flags & (IN6_IFF_NOTREADY | IN6_IFF_CLAT46)) {
      IFA_UNLOCK(ifa);
      continue; /* don't use this interface */
    }
    if (ifa2ia6(ifa)->ia6_flags & IN6_IFF_DETACHED) {
      IFA_UNLOCK(ifa);
      continue;
    }
    if (ifa2ia6(ifa)->ia6_flags & IN6_IFF_DEPRECATED) {
      if (ip6_use_deprecated) {
        IFA_ADDREF_LOCKED(ifa); /* for dep[1] */
        IFA_UNLOCK(ifa);
        if (dep[1] != NULL) {
          IFA_REMREF(&dep[1]->ia_ifa);
        }
        dep[1] = (struct in6_ifaddr *)ifa;
      } else {
        IFA_UNLOCK(ifa);
      }
      continue;
    }
    IFA_ADDREF_LOCKED(ifa); /* for caller */
    IFA_UNLOCK(ifa);
    ifnet_lock_done(ifp);
    if (dep[0] != NULL) {
      IFA_REMREF(&dep[0]->ia_ifa);
    }
    if (dep[1] != NULL) {
      IFA_REMREF(&dep[1]->ia_ifa);
    }
    return (struct in6_ifaddr *)ifa;
  }
  ifnet_lock_done(ifp);

  /* use the last-resort values, that are, deprecated addresses */
  if (dep[0]) {
    if (dep[1] != NULL) {
      IFA_REMREF(&dep[1]->ia_ifa);
    }
    return dep[0];
  }
  if (dep[1]) {
    return dep[1];
  }

  return NULL;
}

/*
 * perform DAD when interface becomes IFF_UP.
 */
static void
in6_if_up_dad_start(struct ifnet *ifp)
{
  struct ifaddr *ifa;
  struct nd_ifinfo *ndi = NULL;

  ndi = ND_IFINFO(ifp);
  VERIFY((NULL != ndi) && (TRUE == ndi->initialized));
  if (!(ndi->flags & ND6_IFF_DAD)) {
    return;
  }

  /* start DAD on all the interface addresses */
  ifnet_lock_exclusive(ifp);
  TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) {
    struct in6_ifaddr *ia6;

    IFA_LOCK_SPIN(ifa);
    if (ifa->ifa_addr->sa_family != AF_INET6) {
      IFA_UNLOCK(ifa);
      continue;
    }
    ia6 = (struct in6_ifaddr *)ifa;
    if (ia6->ia6_flags & IN6_IFF_DADPROGRESS) {
      int delay = 0;  /* delay ticks before DAD output */
      IFA_UNLOCK(ifa);
      nd6_dad_start(ifa, &delay);
    } else {
      IFA_UNLOCK(ifa);
    }
  }
  ifnet_lock_done(ifp);
}

int
in6if_do_dad(
  struct ifnet *ifp)
{
  struct nd_ifinfo *ndi = NULL;

  if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
    return 0;
  }

  ndi = ND_IFINFO(ifp);
  VERIFY((NULL != ndi) && (TRUE == ndi->initialized));
  if (!(ndi->flags & ND6_IFF_DAD)) {
    return 0;
  }

  /*
   * If we are using the alternative neighbor discovery
   * interface on this interface, then skip DAD.
   *
   * Also, skip it for interfaces marked "local private"
   * for now, even when not marked as using the alternative
   * interface.  This is for historical reasons.
   */
  if (ifp->if_eflags &
      (IFEF_IPV6_ND6ALT | IFEF_LOCALNET_PRIVATE | IFEF_DIRECTLINK)) {
    return 0;
  }

  if (ifp->if_family == IFNET_FAMILY_IPSEC ||
      ifp->if_family == IFNET_FAMILY_UTUN) {
    /*
     * Ignore DAD for tunneling virtual interfaces, which get
     * their IPv6 address explicitly assigned.
     */
    return 0;
  }

  switch (ifp->if_type) {
#if IFT_DUMMY
  case IFT_DUMMY:
#endif
  case IFT_FAITH:
    /*
     * These interfaces do not have the IFF_LOOPBACK flag,
     * but loop packets back.  We do not have to do DAD on such
     * interfaces.  We should even omit it, because loop-backed
     * NS would confuse the DAD procedure.
     */
    return 0;
  default:
    /*
     * Our DAD routine requires the interface up and running.
     * However, some interfaces can be up before the RUNNING
     * status.  Additionaly, users may try to assign addresses
     * before the interface becomes up (or running).
     * We simply skip DAD in such a case as a work around.
     * XXX: we should rather mark "tentative" on such addresses,
     * and do DAD after the interface becomes ready.
     */
    if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) !=
        (IFF_UP | IFF_RUNNING)) {
      return 0;
    }

    return 1;
  }
}

/*
 * Calculate max IPv6 MTU through all the interfaces and store it
 * to in6_maxmtu.
 */
void
in6_setmaxmtu(void)
{
  u_int32_t maxmtu = 0;
  struct ifnet *ifp;

  ifnet_head_lock_shared();
  TAILQ_FOREACH(ifp, &ifnet_head, if_list) {
    struct nd_ifinfo *ndi = NULL;

    if ((ndi = ND_IFINFO(ifp)) != NULL && !ndi->initialized) {
      ndi = NULL;
    }
    if (ndi != NULL) {
      lck_mtx_lock(&ndi->lock);
    }
    if ((ifp->if_flags & IFF_LOOPBACK) == 0 &&
        IN6_LINKMTU(ifp) > maxmtu) {
      maxmtu = IN6_LINKMTU(ifp);
    }
    if (ndi != NULL) {
      lck_mtx_unlock(&ndi->lock);
    }
  }
  ifnet_head_done();
  if (maxmtu) {   /* update only when maxmtu is positive */
    in6_maxmtu = maxmtu;
  }
}
/*
 * Provide the length of interface identifiers to be used for the link attached
 * to the given interface.  The length should be defined in "IPv6 over
 * xxx-link" document.  Note that address architecture might also define
 * the length for a particular set of address prefixes, regardless of the
 * link type.  Also see RFC 4862 for additional background.
 */
int
in6_if2idlen(struct ifnet *ifp)
{
  switch (ifp->if_type) {
  case IFT_ETHER:         /* RFC2464 */
  case IFT_IEEE8023ADLAG: /* IEEE802.3ad Link Aggregate */
#ifdef IFT_PROPVIRTUAL
  case IFT_PROPVIRTUAL:   /* XXX: no RFC. treat it as ether */
#endif
#ifdef IFT_L2VLAN
  case IFT_L2VLAN:        /* ditto */
#endif
#ifdef IFT_IEEE80211
  case IFT_IEEE80211:     /* ditto */
#endif
#ifdef IFT_MIP
  case IFT_MIP:   /* ditto */
#endif
    return 64;
  case IFT_FDDI:          /* RFC2467 */
    return 64;
  case IFT_ISO88025:      /* RFC2470 (IPv6 over Token Ring) */
    return 64;
  case IFT_PPP:           /* RFC2472 */
    return 64;
  case IFT_ARCNET:        /* RFC2497 */
    return 64;
  case IFT_FRELAY:        /* RFC2590 */
    return 64;
  case IFT_IEEE1394:      /* RFC3146 */
    return 64;
  case IFT_GIF:
    return 64;    /* draft-ietf-v6ops-mech-v2-07 */
  case IFT_LOOP:
    return 64;    /* XXX: is this really correct? */
  case IFT_OTHER:
    return 64;    /* for utun interfaces */
  case IFT_CELLULAR:
    return 64;    /* Packet Data over Cellular */
  case IFT_BRIDGE:
    return 64;    /* Transparent bridge interface */
  case IFT_6LOWPAN:
    return 64;    /* 6LoWPAN */
  default:
    /*
     * Unknown link type:
     * It might be controversial to use the today's common constant
     * of 64 for these cases unconditionally.  For full compliance,
     * we should return an error in this case.  On the other hand,
     * if we simply miss the standard for the link type or a new
     * standard is defined for a new link type, the IFID length
     * is very likely to be the common constant.  As a compromise,
     * we always use the constant, but make an explicit notice
     * indicating the "unknown" case.
     */
    log(LOG_NOTICE, "%s: unknown link type (%d)\n", __func__,
        ifp->if_type);
    return 64;
  }
}
/*
 * Convert sockaddr_in6 to sockaddr_in.  Original sockaddr_in6 must be
 * v4 mapped addr or v4 compat addr
 */
void
in6_sin6_2_sin(struct sockaddr_in *sin, struct sockaddr_in6 *sin6)
{
  bzero(sin, sizeof(*sin));
  sin->sin_len = sizeof(struct sockaddr_in);
  sin->sin_family = AF_INET;
  sin->sin_port = sin6->sin6_port;
  sin->sin_addr.s_addr = sin6->sin6_addr.s6_addr32[3];
}

/* Convert sockaddr_in to sockaddr_in6 in v4 mapped addr format. */
void
in6_sin_2_v4mapsin6(struct sockaddr_in *sin, struct sockaddr_in6 *sin6)
{
  bzero(sin6, sizeof(*sin6));
  sin6->sin6_len = sizeof(struct sockaddr_in6);
  sin6->sin6_family = AF_INET6;
  sin6->sin6_port = sin->sin_port;
  sin6->sin6_addr.s6_addr32[0] = 0;
  sin6->sin6_addr.s6_addr32[1] = 0;
  if (sin->sin_addr.s_addr) {
    sin6->sin6_addr.s6_addr32[2] = IPV6_ADDR_INT32_SMP;
    sin6->sin6_addr.s6_addr32[3] = sin->sin_addr.s_addr;
  } else {
    sin6->sin6_addr.s6_addr32[2] = 0;
    sin6->sin6_addr.s6_addr32[3] = 0;
  }
}

/* Convert sockaddr_in6 into sockaddr_in. */
void
in6_sin6_2_sin_in_sock(struct sockaddr *nam)
{
  struct sockaddr_in *sin_p;
  struct sockaddr_in6 sin6;

  /*
   * Save original sockaddr_in6 addr and convert it
   * to sockaddr_in.
   */
  sin6 = *(struct sockaddr_in6 *)(void *)nam;
  sin_p = (struct sockaddr_in *)(void *)nam;
  in6_sin6_2_sin(sin_p, &sin6);
}

/* Convert sockaddr_in into sockaddr_in6 in v4 mapped addr format. */
int
in6_sin_2_v4mapsin6_in_sock(struct sockaddr **nam)
{
  struct sockaddr_in *sin_p;
  struct sockaddr_in6 *sin6_p;

  MALLOC(sin6_p, struct sockaddr_in6 *, sizeof(*sin6_p), M_SONAME,
      M_WAITOK);
  if (sin6_p == NULL) {
    return ENOBUFS;
  }
  sin_p = (struct sockaddr_in *)(void *)*nam;
  in6_sin_2_v4mapsin6(sin_p, sin6_p);
  FREE(*nam, M_SONAME);
  *nam = (struct sockaddr *)sin6_p;

  return 0;
}

/*
 * Posts in6_event_data message kernel events.
 *
 * To get the same size of kev_in6_data between ILP32 and LP64 data models
 * we are using a special version of the in6_addrlifetime structure that
 * uses only 32 bits fields to be compatible with Leopard, and that
 * are large enough to span 68 years.
 */
void
in6_post_msg(struct ifnet *ifp, u_int32_t event_code, struct in6_ifaddr *ifa,
    uint8_t *mac)
{
  struct kev_msg ev_msg;
  struct kev_in6_data in6_event_data;
  struct in6_addrlifetime ia6_lt;

  bzero(&in6_event_data, sizeof(struct kev_in6_data));
  bzero(&ev_msg, sizeof(struct kev_msg));
  ev_msg.vendor_code      = KEV_VENDOR_APPLE;
  ev_msg.kev_class        = KEV_NETWORK_CLASS;
  ev_msg.kev_subclass     = KEV_INET6_SUBCLASS;
  ev_msg.event_code       = event_code;

  if (ifa) {
    IFA_LOCK(&ifa->ia_ifa);
    in6_event_data.ia_addr          = ifa->ia_addr;
    in6_event_data.ia_net           = ifa->ia_net;
    in6_event_data.ia_dstaddr       = ifa->ia_dstaddr;
    in6_event_data.ia_prefixmask    = ifa->ia_prefixmask;
    in6_event_data.ia_plen          = ifa->ia_plen;
    in6_event_data.ia6_flags        = (u_int32_t)ifa->ia6_flags;

    /* retrieve time as calendar time (last arg is 1) */
    in6ifa_getlifetime(ifa, &ia6_lt, 1);
    in6_event_data.ia_lifetime.ia6t_expire = (u_int32_t)ia6_lt.ia6t_expire;
    in6_event_data.ia_lifetime.ia6t_preferred = (u_int32_t)ia6_lt.ia6t_preferred;
    in6_event_data.ia_lifetime.ia6t_vltime = ia6_lt.ia6t_vltime;
    in6_event_data.ia_lifetime.ia6t_pltime = ia6_lt.ia6t_pltime;
    IFA_UNLOCK(&ifa->ia_ifa);
  }

  if (ifp != NULL) {
    (void) strlcpy(&in6_event_data.link_data.if_name[0],
        ifp->if_name, IFNAMSIZ);
    in6_event_data.link_data.if_family = ifp->if_family;
    in6_event_data.link_data.if_unit  = (u_int32_t)ifp->if_unit;
  }

  if (mac != NULL) {
    memcpy(&in6_event_data.ia_mac, mac,
        sizeof(in6_event_data.ia_mac));
  }

  ev_msg.dv[0].data_ptr    = &in6_event_data;
  ev_msg.dv[0].data_length = sizeof(in6_event_data);
  ev_msg.dv[1].data_length = 0;

  dlil_post_complete_msg(NULL, &ev_msg);
}

/*
 * Called as part of ip6_init
 */
void
in6_ifaddr_init(void)
{
  in6_cga_init();
  in6_multi_init();

  PE_parse_boot_argn("ifa_debug", &in6ifa_debug, sizeof(in6ifa_debug));

  vm_size_t in6ifa_size = (in6ifa_debug == 0) ? sizeof(struct in6_ifaddr) :
      sizeof(struct in6_ifaddr_dbg);

  in6ifa_zone = zone_create(IN6IFA_ZONE_NAME, in6ifa_size, ZC_ZFREE_CLEARMEM);

  lck_mtx_init(&in6ifa_trash_lock, ifa_mtx_grp, ifa_mtx_attr);
  TAILQ_INIT(&in6ifa_trash_head);
}

static struct in6_ifaddr *
in6_ifaddr_alloc(zalloc_flags_t how)
{
  struct in6_ifaddr *in6ifa;

  in6ifa = zalloc_flags(in6ifa_zone, how | Z_ZERO);
  if (in6ifa != NULL) {
    in6ifa->ia_ifa.ifa_free = in6_ifaddr_free;
    in6ifa->ia_ifa.ifa_debug |= IFD_ALLOC;
    in6ifa->ia_ifa.ifa_del_wc = &in6ifa->ia_ifa.ifa_debug;
    in6ifa->ia_ifa.ifa_del_waiters = 0;
    ifa_lock_init(&in6ifa->ia_ifa);
    if (in6ifa_debug != 0) {
      struct in6_ifaddr_dbg *in6ifa_dbg =
          (struct in6_ifaddr_dbg *)in6ifa;
      in6ifa->ia_ifa.ifa_debug |= IFD_DEBUG;
      in6ifa->ia_ifa.ifa_trace = in6_ifaddr_trace;
      in6ifa->ia_ifa.ifa_attached = in6_ifaddr_attached;
      in6ifa->ia_ifa.ifa_detached = in6_ifaddr_detached;
      ctrace_record(&in6ifa_dbg->in6ifa_alloc);
    }
  }

  return in6ifa;
}

static void
in6_ifaddr_free(struct ifaddr *ifa)
{
  IFA_LOCK_ASSERT_HELD(ifa);

  if (ifa->ifa_refcnt != 0) {
    panic("%s: ifa %p bad ref cnt", __func__, ifa);
    /* NOTREACHED */
  } else if (!(ifa->ifa_debug & IFD_ALLOC)) {
    panic("%s: ifa %p cannot be freed", __func__, ifa);
    /* NOTREACHED */
  }
  if (ifa->ifa_debug & IFD_DEBUG) {
    struct in6_ifaddr_dbg *in6ifa_dbg =
        (struct in6_ifaddr_dbg *)ifa;
    ctrace_record(&in6ifa_dbg->in6ifa_free);
    bcopy(&in6ifa_dbg->in6ifa, &in6ifa_dbg->in6ifa_old,
        sizeof(struct in6_ifaddr));
    if (ifa->ifa_debug & IFD_TRASHED) {
      /* Become a regular mutex, just in case */
      IFA_CONVERT_LOCK(ifa);
      lck_mtx_lock(&in6ifa_trash_lock);
      TAILQ_REMOVE(&in6ifa_trash_head, in6ifa_dbg,
          in6ifa_trash_link);
      lck_mtx_unlock(&in6ifa_trash_lock);
      ifa->ifa_debug &= ~IFD_TRASHED;
    }
  }
  IFA_UNLOCK(ifa);
  ifa_lock_destroy(ifa);
  bzero(ifa, sizeof(struct in6_ifaddr));
  zfree(in6ifa_zone, ifa);
}

static void
in6_ifaddr_attached(struct ifaddr *ifa)
{
  struct in6_ifaddr_dbg *in6ifa_dbg = (struct in6_ifaddr_dbg *)ifa;

  IFA_LOCK_ASSERT_HELD(ifa);

  if (!(ifa->ifa_debug & IFD_DEBUG)) {
    panic("%s: ifa %p has no debug structure", __func__, ifa);
    /* NOTREACHED */
  }
  if (ifa->ifa_debug & IFD_TRASHED) {
    /* Become a regular mutex, just in case */
    IFA_CONVERT_LOCK(ifa);
    lck_mtx_lock(&in6ifa_trash_lock);
    TAILQ_REMOVE(&in6ifa_trash_head, in6ifa_dbg, in6ifa_trash_link);
    lck_mtx_unlock(&in6ifa_trash_lock);
    ifa->ifa_debug &= ~IFD_TRASHED;
  }
}

static void
in6_ifaddr_detached(struct ifaddr *ifa)
{
  struct in6_ifaddr_dbg *in6ifa_dbg = (struct in6_ifaddr_dbg *)ifa;

  IFA_LOCK_ASSERT_HELD(ifa);

  if (!(ifa->ifa_debug & IFD_DEBUG)) {
    panic("%s: ifa %p has no debug structure", __func__, ifa);
    /* NOTREACHED */
  } else if (ifa->ifa_debug & IFD_TRASHED) {
    panic("%s: ifa %p is already in trash list", __func__, ifa);
    /* NOTREACHED */
  }
  ifa->ifa_debug |= IFD_TRASHED;
  /* Become a regular mutex, just in case */
  IFA_CONVERT_LOCK(ifa);
  lck_mtx_lock(&in6ifa_trash_lock);
  TAILQ_INSERT_TAIL(&in6ifa_trash_head, in6ifa_dbg, in6ifa_trash_link);
  lck_mtx_unlock(&in6ifa_trash_lock);
}

static void
in6_ifaddr_trace(struct ifaddr *ifa, int refhold)
{
  struct in6_ifaddr_dbg *in6ifa_dbg = (struct in6_ifaddr_dbg *)ifa;
  ctrace_t *tr;
  u_int32_t idx;
  u_int16_t *cnt;

  if (!(ifa->ifa_debug & IFD_DEBUG)) {
    panic("%s: ifa %p has no debug structure", __func__, ifa);
    /* NOTREACHED */
  }
  if (refhold) {
    cnt = &in6ifa_dbg->in6ifa_refhold_cnt;
    tr = in6ifa_dbg->in6ifa_refhold;
  } else {
    cnt = &in6ifa_dbg->in6ifa_refrele_cnt;
    tr = in6ifa_dbg->in6ifa_refrele;
  }

  idx = atomic_add_16_ov(cnt, 1) % IN6IFA_TRACE_HIST_SIZE;
  ctrace_record(&tr[idx]);
}

/*
 * Handle SIOCGASSOCIDS ioctl for PF_INET6 domain.
 */
static int
in6_getassocids(struct socket *so, uint32_t *cnt, user_addr_t aidp)
{
  struct in6pcb *in6p = sotoin6pcb(so);
  sae_associd_t aid;

  if (in6p == NULL || in6p->inp_state == INPCB_STATE_DEAD) {
    return EINVAL;
  }

  /* IN6PCB has no concept of association */
  aid = SAE_ASSOCID_ANY;
  *cnt = 0;

  /* just asking how many there are? */
  if (aidp == USER_ADDR_NULL) {
    return 0;
  }

  return copyout(&aid, aidp, sizeof(aid));
}

/*
 * Handle SIOCGCONNIDS ioctl for PF_INET6 domain.
 */
static int
in6_getconnids(struct socket *so, sae_associd_t aid, uint32_t *cnt,
    user_addr_t cidp)
{
  struct in6pcb *in6p = sotoin6pcb(so);
  sae_connid_t cid;

  if (in6p == NULL || in6p->inp_state == INPCB_STATE_DEAD) {
    return EINVAL;
  }

  if (aid != SAE_ASSOCID_ANY && aid != SAE_ASSOCID_ALL) {
    return EINVAL;
  }

  /* if connected, return 1 connection count */
  *cnt = ((so->so_state & SS_ISCONNECTED) ? 1 : 0);

  /* just asking how many there are? */
  if (cidp == USER_ADDR_NULL) {
    return 0;
  }

  /* if IN6PCB is connected, assign it connid 1 */
  cid = ((*cnt != 0) ? 1 : SAE_CONNID_ANY);

  return copyout(&cid, cidp, sizeof(cid));
}

/*
 * Handle SIOCGCONNINFO ioctl for PF_INET6 domain.
 */
int
in6_getconninfo(struct socket *so, sae_connid_t cid, uint32_t *flags,
    uint32_t *ifindex, int32_t *soerror, user_addr_t src, socklen_t *src_len,
    user_addr_t dst, socklen_t *dst_len, uint32_t *aux_type,
    user_addr_t aux_data, uint32_t *aux_len)
{
  struct in6pcb *in6p = sotoin6pcb(so);
  struct sockaddr_in6 sin6;
  struct ifnet *ifp = NULL;
  int error = 0;
  u_int32_t copy_len = 0;

  /*
   * Don't test for INPCB_STATE_DEAD since this may be called
   * after SOF_PCBCLEARING is set, e.g. after tcp_close().
   */
  if (in6p == NULL) {
    error = EINVAL;
    goto out;
  }

  if (cid != SAE_CONNID_ANY && cid != SAE_CONNID_ALL && cid != 1) {
    error = EINVAL;
    goto out;
  }

  ifp = in6p->in6p_last_outifp;
  *ifindex = ((ifp != NULL) ? ifp->if_index : 0);
  *soerror = so->so_error;
  *flags = 0;
  if (so->so_state & SS_ISCONNECTED) {
    *flags |= (CIF_CONNECTED | CIF_PREFERRED);
  }
  if (in6p->in6p_flags & INP_BOUND_IF) {
    *flags |= CIF_BOUND_IF;
  }
  if (!(in6p->in6p_flags & INP_IN6ADDR_ANY)) {
    *flags |= CIF_BOUND_IP;
  }
  if (!(in6p->in6p_flags & INP_ANONPORT)) {
    *flags |= CIF_BOUND_PORT;
  }

  bzero(&sin6, sizeof(sin6));
  sin6.sin6_len = sizeof(sin6);
  sin6.sin6_family = AF_INET6;

  /* source address and port */
  sin6.sin6_port = in6p->in6p_lport;
  in6_recoverscope(&sin6, &in6p->in6p_laddr, NULL);
  if (*src_len == 0) {
    *src_len = sin6.sin6_len;
  } else {
    if (src != USER_ADDR_NULL) {
      copy_len = min(*src_len, sizeof(sin6));
      error = copyout(&sin6, src, copy_len);
      if (error != 0) {
        goto out;
      }
      *src_len = copy_len;
    }
  }

  /* destination address and port */
  sin6.sin6_port = in6p->in6p_fport;
  in6_recoverscope(&sin6, &in6p->in6p_faddr, NULL);
  if (*dst_len == 0) {
    *dst_len = sin6.sin6_len;
  } else {
    if (dst != USER_ADDR_NULL) {
      copy_len = min(*dst_len, sizeof(sin6));
      error = copyout(&sin6, dst, copy_len);
      if (error != 0) {
        goto out;
      }
      *dst_len = copy_len;
    }
  }

  if (SOCK_PROTO(so) == IPPROTO_TCP) {
    struct conninfo_tcp tcp_ci;

    *aux_type = CIAUX_TCP;
    if (*aux_len == 0) {
      *aux_len = sizeof(tcp_ci);
    } else {
      if (aux_data != USER_ADDR_NULL) {
        copy_len = min(*aux_len, sizeof(tcp_ci));
        bzero(&tcp_ci, sizeof(tcp_ci));
        tcp_getconninfo(so, &tcp_ci);
        error = copyout(&tcp_ci, aux_data, copy_len);
        if (error != 0) {
          goto out;
        }
        *aux_len = copy_len;
      }
    }
  } else {
    *aux_type = 0;
    *aux_len = 0;
  }

out:
  return error;
}

/*
 * 'u' group ioctls.
 *
 * The switch statement below does nothing at runtime, as it serves as a
 * compile time check to ensure that all of the socket 'u' ioctls (those
 * in the 'u' group going thru soo_ioctl) that are made available by the
 * networking stack is unique.  This works as long as this routine gets
 * updated each time a new interface ioctl gets added.
 *
 * Any failures at compile time indicates duplicated ioctl values.
 */
static __attribute__((unused)) void
in6ioctl_cassert(void)
{
  /*
   * This is equivalent to _CASSERT() and the compiler wouldn't
   * generate any instructions, thus for compile time only.
   */
  switch ((u_long)0) {
  case 0:

  /* bsd/netinet6/in6_var.h */
  case SIOCAADDRCTL_POLICY:
  case SIOCDADDRCTL_POLICY:
  case SIOCDRADD_IN6_32:
  case SIOCDRADD_IN6_64:
  case SIOCDRDEL_IN6_32:
  case SIOCDRDEL_IN6_64:
    ;
  }
}

struct in6_llentry {
  struct llentry          base;
};

#define        IN6_LLTBL_DEFAULT_HSIZE 32
#define        IN6_LLTBL_HASH(k, h) \
  ((((((((k) >> 8) ^ (k)) >> 8) ^ (k)) >> 8) ^ (k)) & ((h) - 1))

/*
 * Do actual deallocation of @lle.
 */
static void
in6_lltable_destroy_lle_unlocked(struct llentry *lle)
{
  LLE_LOCK_DESTROY(lle);
  LLE_REQ_DESTROY(lle);
  FREE(lle, M_LLTABLE);
}

/*
 * Called by LLE_FREE_LOCKED when number of references
 * drops to zero.
 */
static void
in6_lltable_destroy_lle(struct llentry *lle)
{
  LLE_WUNLOCK(lle);
  /* XXX TBD */
  //thread_call_free(lle->lle_timer);
  in6_lltable_destroy_lle_unlocked(lle);
}


static struct llentry *
in6_lltable_new(const struct in6_addr *addr6, uint16_t flags)
{
#pragma unused(flags)
  struct in6_llentry *lle;

  MALLOC(lle, struct in6_llentry *, sizeof(struct in6_llentry), M_LLTABLE, M_NOWAIT | M_ZERO);
  if (lle == NULL) {              /* NB: caller generates msg */
    return NULL;
  }

  lle->base.r_l3addr.addr6 = *addr6;
  lle->base.lle_refcnt = 1;
  lle->base.lle_free = in6_lltable_destroy_lle;
  LLE_LOCK_INIT(&lle->base);
  LLE_REQ_INIT(&lle->base);
#if 0
  /* XXX TBD */
  lle->base.lle_timer = thread_call_allocate(nd6_llinfo_timer, lle);

  if (lle->base.lle_timer == NULL) {
    printf("lle_timer thread call could not be allocated.\n");
    LLE_LOCK_DESTROY(&lle->base);
    LLE_REQ_DESTROY(&lle->base);
    FREE(lle, M_LLTABLE);
    return NULL;
  }
#endif
  return &lle->base;
}

static int
in6_lltable_match_prefix(const struct sockaddr *saddr,
    const struct sockaddr *smask, uint16_t flags, struct llentry *lle)
{
  const struct in6_addr *addr, *mask, *lle_addr;

  addr = &((const struct sockaddr_in6 *)(const void *)saddr)->sin6_addr;
  mask = &((const struct sockaddr_in6 *)(const void *)smask)->sin6_addr;
  lle_addr = &lle->r_l3addr.addr6;

  if (IN6_ARE_MASKED_ADDR_EQUAL(lle_addr, addr, mask) == 0) {
    return 0;
  }

  if (lle->la_flags & LLE_IFADDR) {
    /*
     * Delete LLE_IFADDR records IFF address & flag matches.
     * Note that addr is the interface address within prefix
     * being matched.
     */
    if (IN6_ARE_ADDR_EQUAL(addr, lle_addr) &&
        (flags & LLE_STATIC) != 0) {
      return 1;
    }
    return 0;
  }

  /* flags & LLE_STATIC means deleting both dynamic and static entries */
  if ((flags & LLE_STATIC) || !(lle->la_flags & LLE_STATIC)) {
    return 1;
  }

  return 0;
}

static void
in6_lltable_free_entry(struct lltable *llt, struct llentry *lle)
{
  struct ifnet *ifp;

  LLE_WLOCK_ASSERT(lle);
  KASSERT(llt != NULL, ("lltable is NULL"));

  /* Unlink entry from table */
  if ((lle->la_flags & LLE_LINKED) != 0) {
    ifp = llt->llt_ifp;
    if_afdata_wlock_assert(ifp, llt->llt_af);
    lltable_unlink_entry(llt, lle);
  }

#if 0
  /* XXX TBD */
  if (thread_call_cancel(lle->lle_timer) == TRUE) {
    LLE_REMREF(lle);
  }
#endif
  llentry_free(lle);
}

static int
in6_lltable_rtcheck(struct ifnet *ifp,
    uint16_t flags, const struct sockaddr *l3addr)
{
#pragma unused(flags)
  struct rtentry *rt;

  KASSERT(l3addr->sa_family == AF_INET6,
      ("sin_family %d", l3addr->sa_family));
  /* XXX rtalloc1 should take a const param */
  rt = rtalloc1(__DECONST(struct sockaddr *, l3addr), 0, 0);
  if (rt == NULL || (rt->rt_flags & RTF_GATEWAY) || rt->rt_ifp != ifp) {
    struct ifaddr *ifa;
    /*
     * Create an ND6 cache for an IPv6 neighbor
     * that is not covered by our own prefix.
     */
    /* XXX ifaof_ifpforaddr should take a const param */
    ifa = ifaof_ifpforaddr(__DECONST(struct sockaddr *, l3addr), ifp);
    if (ifa != NULL) {
      IFA_REMREF(ifa);
      if (rt != NULL) {
        rtfree(rt);
      }
      return 0;
    }
    log(LOG_INFO, "IPv6 address: \"%s\" is not on the network\n",
        ip6_sprintf(&((const struct sockaddr_in6 *)(const void *)l3addr)->sin6_addr));
    if (rt != NULL) {
      rtfree(rt);
    }
    return EINVAL;
  }
  rtfree(rt);
  return 0;
}

static inline uint32_t
in6_lltable_hash_dst(const struct in6_addr *dst, uint32_t hsize)
{
  return IN6_LLTBL_HASH(dst->s6_addr32[3], hsize);
}

static uint32_t
in6_lltable_hash(const struct llentry *lle, uint32_t hsize)
{
  return in6_lltable_hash_dst(&lle->r_l3addr.addr6, hsize);
}

static void
in6_lltable_fill_sa_entry(const struct llentry *lle, struct sockaddr *sa)
{
  struct sockaddr_in6 *sin6;

  sin6 = (struct sockaddr_in6 *)(void *)sa;
  bzero(sin6, sizeof(*sin6));
  sin6->sin6_family = AF_INET6;
  sin6->sin6_len = sizeof(*sin6);
  sin6->sin6_addr = lle->r_l3addr.addr6;
}

static inline struct llentry *
in6_lltable_find_dst(struct lltable *llt, const struct in6_addr *dst)
{
  struct llentry *lle;
  struct llentries *lleh;
  u_int hashidx;

  hashidx = in6_lltable_hash_dst(dst, llt->llt_hsize);
  lleh = &llt->lle_head[hashidx];
  LIST_FOREACH(lle, lleh, lle_next) {
    if (lle->la_flags & LLE_DELETED) {
      continue;
    }
    if (IN6_ARE_ADDR_EQUAL(&lle->r_l3addr.addr6, dst)) {
      break;
    }
  }

  return lle;
}

static void
in6_lltable_delete_entry(struct lltable *llt, struct llentry *lle)
{
#pragma unused(llt)
  lle->la_flags |= LLE_DELETED;
  EVENTHANDLER_INVOKE(NULL, lle_event, lle, LLENTRY_DELETED);
#ifdef DIAGNOSTIC
  log(LOG_INFO, "ifaddr cache = %p is deleted\n", lle);
#endif
  llentry_free(lle);
}

static struct llentry *
in6_lltable_alloc(struct lltable *llt, uint16_t flags,
    const struct sockaddr *l3addr)
{
  const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)(const void *)l3addr;
  struct ifnet *ifp = llt->llt_ifp;
  struct llentry *lle;

  KASSERT(l3addr->sa_family == AF_INET6,
      ("sin_family %d", l3addr->sa_family));

  /*
   * A route that covers the given address must have
   * been installed 1st because we are doing a resolution,
   * verify this.
   */
  if (!(flags & LLE_IFADDR) &&
      in6_lltable_rtcheck(ifp, flags, l3addr) != 0) {
    return NULL;
  }

  lle = in6_lltable_new(&sin6->sin6_addr, flags);
  if (lle == NULL) {
    log(LOG_INFO, "lla_lookup: new lle malloc failed\n");
    return NULL;
  }
  lle->la_flags = (uint16_t)flags;
  if ((flags & LLE_IFADDR) == LLE_IFADDR) {
    lltable_set_entry_addr(ifp, lle, LLADDR(SDL(ifp->if_lladdr->ifa_addr)));
    lle->la_flags |= LLE_STATIC;
  }

  if ((lle->la_flags & LLE_STATIC) != 0) {
    lle->ln_state = ND6_LLINFO_REACHABLE;
  }

  return lle;
}

static struct llentry *
in6_lltable_lookup(struct lltable *llt, uint16_t flags,
    const struct sockaddr *l3addr)
{
  const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)(const void *)l3addr;
  struct llentry *lle;

  IF_AFDATA_LOCK_ASSERT(llt->llt_ifp, llt->llt_af);
  KASSERT(l3addr->sa_family == AF_INET6,
      ("sin_family %d", l3addr->sa_family));

  lle = in6_lltable_find_dst(llt, &sin6->sin6_addr);

  if (lle == NULL) {
    return NULL;
  }

  KASSERT((flags & (LLE_UNLOCKED | LLE_EXCLUSIVE)) !=
      (LLE_UNLOCKED | LLE_EXCLUSIVE), ("wrong lle request flags: 0x%X",
      flags));

  if (flags & LLE_UNLOCKED) {
    return lle;
  }

  if (flags & LLE_EXCLUSIVE) {
    LLE_WLOCK(lle);
  } else {
    LLE_RLOCK(lle);
  }
  return lle;
}

static int
in6_lltable_dump_entry(struct lltable *llt, struct llentry *lle,
    struct sysctl_req *wr)
{
  struct ifnet *ifp = llt->llt_ifp;
  /* XXX stack use */
  struct {
    struct rt_msghdr        rtm;
    struct sockaddr_in6     sin6;
    /*
     * ndp.c assumes that sdl is word aligned
     */
#ifdef __LP64__
    uint32_t                pad;
#endif
    struct sockaddr_dl      sdl;
  } ndpc;
  struct sockaddr_dl *sdl;
  int error;

  bzero(&ndpc, sizeof(ndpc));
  /* skip deleted entries */
  if ((lle->la_flags & LLE_DELETED) == LLE_DELETED) {
    return 0;
  }
  /* Skip if jailed and not a valid IP of the prison. */
  lltable_fill_sa_entry(lle,
      (struct sockaddr *)&ndpc.sin6);
  /*
   * produce a msg made of:
   *  struct rt_msghdr;
   *  struct sockaddr_in6 (IPv6)
   *  struct sockaddr_dl;
   */
  ndpc.rtm.rtm_msglen = sizeof(ndpc);
  ndpc.rtm.rtm_version = RTM_VERSION;
  ndpc.rtm.rtm_type = RTM_GET;
  ndpc.rtm.rtm_flags = RTF_UP;
  ndpc.rtm.rtm_addrs = RTA_DST | RTA_GATEWAY;

  /* publish */
  if (lle->la_flags & LLE_PUB) {
    ndpc.rtm.rtm_flags |= RTF_ANNOUNCE;
  }
  sdl = &ndpc.sdl;
  sdl->sdl_family = AF_LINK;
  sdl->sdl_len = sizeof(*sdl);
  sdl->sdl_index = ifp->if_index;
  sdl->sdl_type = ifp->if_type;
  if ((lle->la_flags & LLE_VALID) == LLE_VALID) {
    sdl->sdl_alen = ifp->if_addrlen;
    bcopy(&lle->ll_addr, LLADDR(sdl), ifp->if_addrlen);
  } else {
    sdl->sdl_alen = 0;
    bzero(LLADDR(sdl), ifp->if_addrlen);
  }
  if (lle->la_expire != 0) {
    clock_sec_t secs;
    clock_usec_t usecs;

    clock_get_calendar_microtime(&secs, &usecs);
    ndpc.rtm.rtm_rmx.rmx_expire = (int32_t)(lle->la_expire +
        lle->lle_remtime / hz +
        secs - net_uptime());
  }
  ndpc.rtm.rtm_flags |= (RTF_HOST | RTF_LLDATA);
  if (lle->la_flags & LLE_STATIC) {
    ndpc.rtm.rtm_flags |= RTF_STATIC;
  }
  if (lle->la_flags & LLE_IFADDR) {
    ndpc.rtm.rtm_flags |= RTF_PINNED;
  }
  if (lle->ln_router != 0) {
    ndpc.rtm.rtm_flags |= RTF_GATEWAY;
  }
  ndpc.rtm.rtm_rmx.rmx_pksent = lle->la_asked;
  /* Store state in rmx_weight value */
  ndpc.rtm.rtm_rmx.rmx_state = lle->ln_state;
  ndpc.rtm.rtm_index = ifp->if_index;
  error = SYSCTL_OUT(wr, &ndpc, sizeof(ndpc));

  return error;
}

struct lltable *
in6_lltattach(struct ifnet *ifp)
{
  struct lltable *llt;

  llt = lltable_allocate_htbl(IN6_LLTBL_DEFAULT_HSIZE);
  llt->llt_af = AF_INET6;
  llt->llt_ifp = ifp;

  llt->llt_lookup = in6_lltable_lookup;
  llt->llt_alloc_entry = in6_lltable_alloc;
  llt->llt_delete_entry = in6_lltable_delete_entry;
  llt->llt_dump_entry = in6_lltable_dump_entry;
  llt->llt_hash = in6_lltable_hash;
  llt->llt_fill_sa_entry = in6_lltable_fill_sa_entry;
  llt->llt_free_entry = in6_lltable_free_entry;
  llt->llt_match_prefix = in6_lltable_match_prefix;
  lltable_link(llt);

  return llt;
}

void
in6_ip6_to_sockaddr(const struct in6_addr *ip6, u_int16_t port,
    struct sockaddr_in6 *sin6, u_int32_t maxlen)
{
  if (maxlen < sizeof(struct sockaddr_in6)) {
    return;
  }

  *sin6 = (struct sockaddr_in6) {
    .sin6_family = AF_INET6,
    .sin6_len = sizeof(*sin6),
    .sin6_port = port,
    .sin6_addr = *ip6,
  };

  if (IN6_IS_SCOPE_EMBED(&sin6->sin6_addr)) {
    sin6->sin6_scope_id = ntohs(sin6->sin6_addr.s6_addr16[1]);
    sin6->sin6_addr.s6_addr16[1] = 0;
  }
}

/* IPv6 events */
struct in6_event {
  in6_evhdlr_code_t in6_event_code;
  struct ifnet *in6_ifp;
  struct in6_addr in6_address;
  uint32_t val;
};

struct in6_event2kev in6_event2kev_array[IN6_EVENT_MAX] = {
  {
    .in6_event_code = IN6_ADDR_MARKED_DUPLICATED,
    .in6_event_kev_subclass = KEV_ND6_SUBCLASS,
    .in6_event_kev_code = KEV_ND6_DAD_FAILURE,
    .in6_event_str = "IN6_ADDR_MARKED_DUPLICATED",
  },
  {
    .in6_event_code = IN6_ADDR_MARKED_DETACHED,
    .in6_event_kev_subclass = KEV_ND6_SUBCLASS,
    .in6_event_kev_code = KEV_ND6_ADDR_DETACHED,
    .in6_event_str = "IN6_ADDR_MARKED_DETACHED",
  },
  {
    .in6_event_code = IN6_ADDR_MARKED_DEPRECATED,
    .in6_event_kev_subclass = KEV_ND6_SUBCLASS,
    .in6_event_kev_code = KEV_ND6_ADDR_DEPRECATED,
    .in6_event_str = "IN6_ADDR_MARKED_DEPRECATED",
  },
  {
    .in6_event_code = IN6_NDP_RTR_EXPIRY,
    .in6_event_kev_subclass = KEV_ND6_SUBCLASS,
    .in6_event_kev_code = KEV_ND6_RTR_EXPIRED,
    .in6_event_str = "IN6_NDP_RTR_EXPIRY",
  },
  {
    .in6_event_code = IN6_NDP_PFX_EXPIRY,
    .in6_event_kev_subclass = KEV_ND6_SUBCLASS,
    .in6_event_kev_code = KEV_ND6_PFX_EXPIRED,
    .in6_event_str = "IN6_NDP_PFX_EXPIRY",
  },
  {
    .in6_event_code = IN6_NDP_ADDR_EXPIRY,
    .in6_event_kev_subclass = KEV_ND6_SUBCLASS,
    .in6_event_kev_code = KEV_ND6_ADDR_EXPIRED,
    .in6_event_str = "IN6_NDP_ADDR_EXPIRY",
  },
};

void
in6_eventhdlr_callback(struct eventhandler_entry_arg arg0 __unused,
    in6_evhdlr_code_t in6_ev_code, struct ifnet *ifp,
    struct in6_addr *p_addr6, uint32_t val)
{
  struct kev_msg ev_msg;
  struct kev_nd6_event nd6_event;

  bzero(&ev_msg, sizeof(ev_msg));
  bzero(&nd6_event, sizeof(nd6_event));

  nd6log0(info, "%s Event %s received for %s\n",
      __func__, in6_event2kev_array[in6_ev_code].in6_event_str,
      ip6_sprintf(p_addr6));

  ev_msg.vendor_code      = KEV_VENDOR_APPLE;
  ev_msg.kev_class        = KEV_NETWORK_CLASS;
  ev_msg.kev_subclass     =
      in6_event2kev_array[in6_ev_code].in6_event_kev_subclass;
  ev_msg.event_code       =
      in6_event2kev_array[in6_ev_code].in6_event_kev_code;

  nd6_event.link_data.if_family = ifp->if_family;
  nd6_event.link_data.if_unit = ifp->if_unit;
  strlcpy(nd6_event.link_data.if_name, ifp->if_name,
      sizeof(nd6_event.link_data.if_name));

  VERIFY(p_addr6 != NULL);
  bcopy(p_addr6, &nd6_event.in6_address,
      sizeof(nd6_event.in6_address));
  nd6_event.val = val;

  ev_msg.dv[0].data_ptr = &nd6_event;
  ev_msg.dv[0].data_length = sizeof(nd6_event);

  kev_post_msg(&ev_msg);
}

static void
in6_event_callback(void *arg)
{
  struct in6_event *p_in6_ev = (struct in6_event *)arg;

  EVENTHANDLER_INVOKE(&in6_evhdlr_ctxt, in6_event,
      p_in6_ev->in6_event_code, p_in6_ev->in6_ifp,
      &p_in6_ev->in6_address, p_in6_ev->val);
}

struct in6_event_nwk_wq_entry {
  struct nwk_wq_entry nwk_wqe;
  struct in6_event in6_ev_arg;
};

void
in6_event_enqueue_nwk_wq_entry(in6_evhdlr_code_t in6_event_code,
    struct ifnet *ifp, struct in6_addr *p_addr6,
    uint32_t val)
{
  struct in6_event_nwk_wq_entry *p_in6_ev = NULL;

  MALLOC(p_in6_ev, struct in6_event_nwk_wq_entry *,
      sizeof(struct in6_event_nwk_wq_entry),
      M_NWKWQ, M_WAITOK | M_ZERO);

  p_in6_ev->nwk_wqe.func = in6_event_callback;
  p_in6_ev->nwk_wqe.is_arg_managed = TRUE;
  p_in6_ev->nwk_wqe.arg = &p_in6_ev->in6_ev_arg;

  p_in6_ev->in6_ev_arg.in6_event_code = in6_event_code;
  p_in6_ev->in6_ev_arg.in6_ifp = ifp;
  if (p_addr6 != NULL) {
    bcopy(p_addr6, &p_in6_ev->in6_ev_arg.in6_address,
        sizeof(p_in6_ev->in6_ev_arg.in6_address));
  }
  p_in6_ev->in6_ev_arg.val = val;

  nwk_wq_enqueue((struct nwk_wq_entry*)p_in6_ev);
}

/*
 * Caller must hold in6_ifaddr_rwlock as writer.
 */
static void
in6_iahash_remove(struct in6_ifaddr *ia)
{
  LCK_RW_ASSERT(&in6_ifaddr_rwlock, LCK_RW_ASSERT_EXCLUSIVE);
  IFA_LOCK_ASSERT_HELD(&ia->ia_ifa);

  if (!IA6_IS_HASHED(ia)) {
    panic("%s: attempt to remove wrong ia %p from ipv6 hash table\n", __func__, ia);
    /* NOTREACHED */
  }
  TAILQ_REMOVE(IN6ADDR_HASH(&ia->ia_addr.sin6_addr), ia, ia6_hash);
  IA6_HASH_INIT(ia);
  if (IFA_REMREF_LOCKED(&ia->ia_ifa) == NULL) {
    panic("%s: unexpected (missing) refcnt ifa=%p", __func__,
        &ia->ia_ifa);
    /* NOTREACHED */
  }
}

/*
 * Caller must hold in6_ifaddr_rwlock as writer.
 */
static void
in6_iahash_insert(struct in6_ifaddr *ia)
{
  LCK_RW_ASSERT(&in6_ifaddr_rwlock, LCK_RW_ASSERT_EXCLUSIVE);
  IFA_LOCK_ASSERT_HELD(&ia->ia_ifa);

  if (ia->ia_addr.sin6_family != AF_INET6) {
    panic("%s: attempt to insert wrong ia %p into hash table\n", __func__, ia);
    /* NOTREACHED */
  } else if (IA6_IS_HASHED(ia)) {
    panic("%s: attempt to double-insert ia %p into hash table\n", __func__, ia);
    /* NOTREACHED */
  }
  TAILQ_INSERT_HEAD(IN6ADDR_HASH(&ia->ia_addr.sin6_addr),
      ia, ia6_hash);
  IFA_ADDREF_LOCKED(&ia->ia_ifa);
}

/*
 * Some point to point interfaces that are tunnels borrow the address from
 * an underlying interface (e.g. VPN server). In order for source address
 * selection logic to find the underlying interface first, we add the address
 * of borrowing point to point interfaces at the end of the list.
 * (see rdar://6733789)
 *
 * Caller must hold in6_ifaddr_rwlock as writer.
 */
static void
in6_iahash_insert_ptp(struct in6_ifaddr *ia)
{
  struct in6_ifaddr *tmp_ifa;
  struct ifnet *tmp_ifp;

  LCK_RW_ASSERT(&in6_ifaddr_rwlock, LCK_RW_ASSERT_EXCLUSIVE);
  IFA_LOCK_ASSERT_HELD(&ia->ia_ifa);

  if (ia->ia_addr.sin6_family != AF_INET6) {
    panic("%s: attempt to insert wrong ia %p into hash table\n", __func__, ia);
    /* NOTREACHED */
  } else if (IA6_IS_HASHED(ia)) {
    panic("%s: attempt to double-insert ia %p into hash table\n", __func__, ia);
    /* NOTREACHED */
  }
  IFA_UNLOCK(&ia->ia_ifa);
  TAILQ_FOREACH(tmp_ifa, IN6ADDR_HASH(&ia->ia_addr.sin6_addr), ia6_hash) {
    IFA_LOCK(&tmp_ifa->ia_ifa);
    /* ia->ia_addr won't change, so check without lock */
    if (IN6_ARE_ADDR_EQUAL(&tmp_ifa->ia_addr.sin6_addr, &ia->ia_addr.sin6_addr)) {
      IFA_UNLOCK(&tmp_ifa->ia_ifa);
      break;
    }
    IFA_UNLOCK(&tmp_ifa->ia_ifa);
  }
  tmp_ifp = (tmp_ifa == NULL) ? NULL : tmp_ifa->ia_ifp;

  IFA_LOCK(&ia->ia_ifa);
  if (tmp_ifp == NULL) {
    TAILQ_INSERT_HEAD(IN6ADDR_HASH(&ia->ia_addr.sin6_addr),
        ia, ia6_hash);
  } else {
    TAILQ_INSERT_TAIL(IN6ADDR_HASH(&ia->ia_addr.sin6_addr),
        ia, ia6_hash);
  }
  IFA_ADDREF_LOCKED(&ia->ia_ifa);
}

Coverage Report

Created: 2026-11-12 06:44