root/netinet6/nd6_nbr.c

DEFINITIONS

1. nd6_ns_input
2. nd6_ns_output
3. nd6_na_input
4. nd6_na_output
5. nd6_ifptomac
6. nd6_dad_find
7. nd6_dad_starttimer
8. nd6_dad_stoptimer
9. nd6_dad_start
10. nd6_dad_stop
11. nd6_dad_timer
12. nd6_dad_duplicated
13. nd6_dad_ns_output
14. nd6_dad_ns_input
15. nd6_dad_na_input

    1 /*      $OpenBSD: nd6_nbr.c,v 1.45 2007/06/08 09:31:38 henning Exp $    */
    2 /*      $KAME: nd6_nbr.c,v 1.61 2001/02/10 16:06:14 jinmei Exp $        */
    4 /*
    5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
    6  * All rights reserved.
    7  *
    8  * Redistribution and use in source and binary forms, with or without
    9  * modification, are permitted provided that the following conditions
   10  * are met:
   11  * 1. Redistributions of source code must retain the above copyright
   12  *    notice, this list of conditions and the following disclaimer.
   13  * 2. Redistributions in binary form must reproduce the above copyright
   14  *    notice, this list of conditions and the following disclaimer in the
   15  *    documentation and/or other materials provided with the distribution.
   16  * 3. Neither the name of the project nor the names of its contributors
   17  *    may be used to endorse or promote products derived from this software
   18  *    without specific prior written permission.
   19  *
   20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
   21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
   24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   30  * SUCH DAMAGE.
   31  */
   33 #include <sys/param.h>
   34 #include <sys/systm.h>
   35 #include <sys/malloc.h>
   36 #include <sys/mbuf.h>
   37 #include <sys/socket.h>
   38 #include <sys/sockio.h>
   39 #include <sys/time.h>
   40 #include <sys/kernel.h>
   41 #include <sys/errno.h>
   42 #include <sys/ioctl.h>
   43 #include <sys/syslog.h>
   44 #include <sys/queue.h>
   45 #include <sys/timeout.h>
   47 #include <net/if.h>
   48 #include <net/if_types.h>
   49 #include <net/if_dl.h>
   50 #include <net/route.h>
   52 #include <netinet/in.h>
   53 #include <netinet/in_var.h>
   54 #include <netinet6/in6_var.h>
   55 #include <netinet/ip6.h>
   56 #include <netinet6/ip6_var.h>
   57 #include <netinet6/nd6.h>
   58 #include <netinet/icmp6.h>
   60 #include <dev/rndvar.h>
   62 #include "carp.h"
   63 #if NCARP > 0
   64 #include <netinet/ip_carp.h>
   65 #endif
   67 #define SDL(s) ((struct sockaddr_dl *)s)
   69 struct dadq;
   70 static struct dadq *nd6_dad_find(struct ifaddr *);
   71 static void nd6_dad_starttimer(struct dadq *, int);
   72 static void nd6_dad_stoptimer(struct dadq *);
   73 static void nd6_dad_timer(struct ifaddr *);
   74 static void nd6_dad_ns_output(struct dadq *, struct ifaddr *);
   75 static void nd6_dad_ns_input(struct ifaddr *);
   76 static void nd6_dad_na_input(struct ifaddr *);
   78 static int dad_ignore_ns = 0;   /* ignore NS in DAD - specwise incorrect*/
   79 static int dad_maxtry = 15;     /* max # of *tries* to transmit DAD packet */
   81 /*
   82  * Input an Neighbor Solicitation Message.
   83  *
   84  * Based on RFC 2461
   85  * Based on RFC 2462 (duplicated address detection)
   86  */
   87 void
nd6_ns_input(m, off, icmp6len)
   89         struct mbuf *m;
   90         int off, icmp6len;
   91 {
   92         struct ifnet *ifp = m->m_pkthdr.rcvif;
   93         struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
   94         struct nd_neighbor_solicit *nd_ns;
   95         struct in6_addr saddr6 = ip6->ip6_src;
   96         struct in6_addr daddr6 = ip6->ip6_dst;
   97         struct in6_addr taddr6;
   98         struct in6_addr myaddr6;
   99         char *lladdr = NULL;
  100         struct ifaddr *ifa = NULL;
  101         int lladdrlen = 0;
  102         int anycast = 0, proxy = 0, tentative = 0;
  103         int router = ip6_forwarding;
  104         int tlladdr;
  105         union nd_opts ndopts;
  106         struct sockaddr_dl *proxydl = NULL;
IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len);
  109         if (nd_ns == NULL) {
icmp6stat.icp6s_tooshort++;
  111                 return;
  112         }
ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */
taddr6 = nd_ns->nd_ns_target;
  116         if (ip6->ip6_hlim != 255) {
nd6log((LOG_ERR,
  118                     "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n",
ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src),
ip6_sprintf(&ip6->ip6_dst), ifp->if_xname));
  121                 goto bad;
  122         }
  124         if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
  125                 /* dst has to be solicited node multicast address. */
  126                 /* don't check ifindex portion */
  127                 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL &&
daddr6.s6_addr32[1] == 0 &&
daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE &&
daddr6.s6_addr8[12] == 0xff) {
  131                         ; /*good*/
  132                 } else {
nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
  134                             "(wrong ip6 dst)\n"));
  135                         goto bad;
  136                 }
  137         }
  139         if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n"));
  141                 goto bad;
  142         }
  144         if (IN6_IS_SCOPE_EMBED(&taddr6))
taddr6.s6_addr16[1] = htons(ifp->if_index);
icmp6len -= sizeof(*nd_ns);
nd6_option_init(nd_ns + 1, icmp6len, &ndopts);
  149         if (nd6_options(&ndopts) < 0) {
nd6log((LOG_INFO,
  151                     "nd6_ns_input: invalid ND option, ignored\n"));
  152                 /* nd6_options have incremented stats */
  153                 goto freeit;
  154         }
  156         if (ndopts.nd_opts_src_lladdr) {
lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
  159         }
  161         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) {
nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
  163                     "(link-layer address option)\n"));
  164                 goto bad;
  165         }
  167         /*
  168          * Attaching target link-layer address to the NA?
  169          * (RFC 2461 7.2.4)
  170          *
  171          * NS IP dst is unicast/anycast                 MUST NOT add
  172          * NS IP dst is solicited-node multicast        MUST add
  173          *
  174          * In implementation, we add target link-layer address by default.
  175          * We do not add one in MUST NOT cases.
  176          */
  177 #if 0 /* too much! */
ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6);
  179         if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST))
tlladdr = 0;
  181         else
  182 #endif
  183         if (!IN6_IS_ADDR_MULTICAST(&daddr6))
tlladdr = 0;
  185         else
tlladdr = 1;
  188         /*
  189          * Target address (taddr6) must be either:
  190          * (1) Valid unicast/anycast address for my receiving interface,
  191          * (2) Unicast address for which I'm offering proxy service, or
  192          * (3) "tentative" address on which DAD is being performed.
  193          */
  194         /* (1) and (3) check. */
  195 #if NCARP > 0
  196         if (ifp->if_type == IFT_CARP) {
ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
  198                 if (ifa && !carp_iamatch6(ifp, ifa))
ifa = NULL;
  200         } else {
ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
  202         }
  203 #else
ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
  205 #endif
  207         /* (2) check. */
  208         if (!ifa) {
  209                 struct rtentry *rt;
  210                 struct sockaddr_in6 tsin6;
bzero(&tsin6, sizeof tsin6);
tsin6.sin6_len = sizeof(struct sockaddr_in6);
tsin6.sin6_family = AF_INET6;
tsin6.sin6_addr = taddr6;
rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0);
  218                 if (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 &&
rt->rt_gateway->sa_family == AF_LINK) {
  220                         /*
  221                          * proxy NDP for single entry
  222                          */
ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp,
IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
  225                         if (ifa) {
proxy = 1;
proxydl = SDL(rt->rt_gateway);
router = 0;     /* XXX */
  229                         }
  230                 }
  231                 if (rt)
rtfree(rt);
  233         }
  234         if (!ifa) {
  235                 /*
  236                  * We've got an NS packet, and we don't have that address
  237                  * assigned for us.  We MUST silently ignore it.
  238                  * See RFC2461 7.2.3.
  239                  */
  240                 goto freeit;
  241         }
myaddr6 = *IFA_IN6(ifa);
anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST;
tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE;
  245         if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED)
  246                 goto freeit;
  248         if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s "
  250                     "(if %d, NS packet %d)\n",
ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2));
  252                 goto bad;
  253         }
  255         if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) {
log(LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n",
ip6_sprintf(&saddr6));
  258                 goto freeit;
  259         }
  261         /*
  262          * We have neighbor solicitation packet, with target address equals to
  263          * one of my tentative address.
  264          *
  265          * src addr     how to process?
  266          * ---          ---
  267          * multicast    of course, invalid (rejected in ip6_input)
  268          * unicast      somebody is doing address resolution -> ignore
  269          * unspec       dup address detection
  270          *
  271          * The processing is defined in RFC 2462.
  272          */
  273         if (tentative) {
  274                 /*
  275                  * If source address is unspecified address, it is for
  276                  * duplicated address detection.
  277                  *
  278                  * If not, the packet is for address resolution;
  279                  * silently ignore it.
  280                  */
  281                 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6))
nd6_dad_ns_input(ifa);
  284                 goto freeit;
  285         }
  287         /*
  288          * If the source address is unspecified address, entries must not
  289          * be created or updated.
  290          * It looks that sender is performing DAD.  Output NA toward
  291          * all-node multicast address, to tell the sender that I'm using
  292          * the address.
  293          * S bit ("solicited") must be zero.
  294          */
  295         if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
saddr6 = in6addr_linklocal_allnodes;
saddr6.s6_addr16[1] = htons(ifp->if_index);
nd6_na_output(ifp, &saddr6, &taddr6,
  299                     ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
  300                     (router ? ND_NA_FLAG_ROUTER : 0),
tlladdr, (struct sockaddr *)proxydl);
  302                 goto freeit;
  303         }
nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_NEIGHBOR_SOLICIT, 0);
nd6_na_output(ifp, &saddr6, &taddr6,
  308             ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
  309             (router ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED,
tlladdr, (struct sockaddr *)proxydl);
freeit:
m_freem(m);
  313         return;
bad:
nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", ip6_sprintf(&saddr6)));
nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", ip6_sprintf(&daddr6)));
nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", ip6_sprintf(&taddr6)));
icmp6stat.icp6s_badns++;
m_freem(m);
  321 }
  323 /*
  324  * Output an Neighbor Solicitation Message. Caller specifies:
  325  *      - ICMP6 header source IP6 address
  326  *      - ND6 header target IP6 address
  327  *      - ND6 header source datalink address
  328  *
  329  * Based on RFC 2461
  330  * Based on RFC 2462 (duplicated address detection)
  331  */
  332 void
nd6_ns_output(ifp, daddr6, taddr6, ln, dad)
  334         struct ifnet *ifp;
  335         struct in6_addr *daddr6, *taddr6;
  336         struct llinfo_nd6 *ln;  /* for source address determination */
  337         int dad;        /* duplicated address detection */
  338 {
  339         struct mbuf *m;
  340         struct ip6_hdr *ip6;
  341         struct nd_neighbor_solicit *nd_ns;
  342         struct sockaddr_in6 src_sa, dst_sa;
  343         struct ip6_moptions im6o;
  344         int icmp6len;
  345         int maxlen;
caddr_t mac;
  347         struct route_in6 ro;
bzero(&ro, sizeof(ro));
  351         if (IN6_IS_ADDR_MULTICAST(taddr6))
  352                 return;
  354         /* estimate the size of message */
maxlen = sizeof(*ip6) + sizeof(*nd_ns);
maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
  357 #ifdef DIAGNOSTIC
  358         if (max_linkhdr + maxlen >= MCLBYTES) {
printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES "
  360                     "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
panic("nd6_ns_output: insufficient MCLBYTES");
  362                 /* NOTREACHED */
  363         }
  364 #endif
MGETHDR(m, M_DONTWAIT, MT_DATA);
  367         if (m && max_linkhdr + maxlen >= MHLEN) {
MCLGET(m, M_DONTWAIT);
  369                 if ((m->m_flags & M_EXT) == 0) {
m_free(m);
m = NULL;
  372                 }
  373         }
  374         if (m == NULL)
  375                 return;
m->m_pkthdr.rcvif = NULL;
  378         if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) {
m->m_flags |= M_MCAST;
im6o.im6o_multicast_ifp = ifp;
im6o.im6o_multicast_hlim = 255;
im6o.im6o_multicast_loop = 0;
  383         }
icmp6len = sizeof(*nd_ns);
m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len;
m->m_data += max_linkhdr;       /* or MH_ALIGN() equivalent? */
  389         /* fill neighbor solicitation packet */
ip6 = mtod(m, struct ip6_hdr *);
ip6->ip6_flow = 0;
ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
ip6->ip6_vfc |= IPV6_VERSION;
  394         /* ip6->ip6_plen will be set later */
ip6->ip6_nxt = IPPROTO_ICMPV6;
ip6->ip6_hlim = 255;
  397         /* determine the source and destination addresses */
bzero(&src_sa, sizeof(src_sa));
bzero(&dst_sa, sizeof(dst_sa));
src_sa.sin6_family = dst_sa.sin6_family = AF_INET6;
src_sa.sin6_len = dst_sa.sin6_len = sizeof(struct sockaddr_in6);
  402         if (daddr6)
dst_sa.sin6_addr = *daddr6;
  404         else {
dst_sa.sin6_addr.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
dst_sa.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
dst_sa.sin6_addr.s6_addr32[1] = 0;
dst_sa.sin6_addr.s6_addr32[2] = IPV6_ADDR_INT32_ONE;
dst_sa.sin6_addr.s6_addr32[3] = taddr6->s6_addr32[3];
dst_sa.sin6_addr.s6_addr8[12] = 0xff;
  411         }
ip6->ip6_dst = dst_sa.sin6_addr;
  413         if (!dad) {
  414                 /*
  415                  * RFC2461 7.2.2:
  416                  * "If the source address of the packet prompting the
  417                  * solicitation is the same as one of the addresses assigned
  418                  * to the outgoing interface, that address SHOULD be placed
  419                  * in the IP Source Address of the outgoing solicitation.
  420                  * Otherwise, any one of the addresses assigned to the
  421                  * interface should be used."
  422                  *
  423                  * We use the source address for the prompting packet
  424                  * (saddr6), if:
  425                  * - saddr6 is given from the caller (by giving "ln"), and
  426                  * - saddr6 belongs to the outgoing interface.
  427                  * Otherwise, we perform the source address selection as usual.
  428                  */
  429                 struct ip6_hdr *hip6;           /* hold ip6 */
  430                 struct in6_addr *saddr6;
  432                 if (ln && ln->ln_hold) {
hip6 = mtod(ln->ln_hold, struct ip6_hdr *);
  434                         /* XXX pullup? */
  435                         if (sizeof(*hip6) < ln->ln_hold->m_len)
saddr6 = &hip6->ip6_src;
  437                         else
saddr6 = NULL;
  439                 } else
saddr6 = NULL;
  441                 if (saddr6 && in6ifa_ifpwithaddr(ifp, saddr6))
src_sa.sin6_addr = *saddr6;
  443                 else {
  444                         struct in6_addr *src0;
  445                         int error;
bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa));
src0 = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL,
  449                             &error);
  450                         if (src0 == NULL) {
nd6log((LOG_DEBUG,
  452                                     "nd6_ns_output: source can't be "
  453                                     "determined: dst=%s, error=%d\n",
ip6_sprintf(&dst_sa.sin6_addr), error));
  455                                 goto bad;
  456                         }
src_sa.sin6_addr = *src0;
  458                 }
  459         } else {
  460                 /*
  461                  * Source address for DAD packet must always be IPv6
  462                  * unspecified address. (0::0)
  463                  * We actually don't have to 0-clear the address (we did it
  464                  * above), but we do so here explicitly to make the intention
  465                  * clearer.
  466                  */
bzero(&src_sa.sin6_addr, sizeof(src_sa.sin6_addr));
  468         }
ip6->ip6_src = src_sa.sin6_addr;
nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1);
nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT;
nd_ns->nd_ns_code = 0;
nd_ns->nd_ns_reserved = 0;
nd_ns->nd_ns_target = *taddr6;
  476         if (IN6_IS_SCOPE_EMBED(&nd_ns->nd_ns_target))
nd_ns->nd_ns_target.s6_addr16[1] = 0;
  479         /*
  480          * Add source link-layer address option.
  481          *
  482          *                              spec            implementation
  483          *                              ---             ---
  484          * DAD packet                   MUST NOT        do not add the option
  485          * there's no link layer address:
  486          *                              impossible      do not add the option
  487          * there's link layer address:
  488          *      Multicast NS            MUST add one    add the option
  489          *      Unicast NS              SHOULD add one  add the option
  490          */
  491         if (!dad && (mac = nd6_ifptomac(ifp))) {
  492                 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
  493                 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
  494                 /* 8 byte alignments... */
optlen = (optlen + 7) & ~7;
m->m_pkthdr.len += optlen;
m->m_len += optlen;
icmp6len += optlen;
bzero((caddr_t)nd_opt, optlen);
nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR;
nd_opt->nd_opt_len = optlen >> 3;
bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
  504         }
ip6->ip6_plen = htons((u_short)icmp6len);
nd_ns->nd_ns_cksum = 0;
nd_ns->nd_ns_cksum =
in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len);
ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL);
icmp6_ifstat_inc(ifp, ifs6_out_msg);
icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit);
icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++;
  516         if (ro.ro_rt) {         /* we don't cache this route. */
RTFREE(ro.ro_rt);
  518         }
  519         return;
bad:
  522         if (ro.ro_rt) {
RTFREE(ro.ro_rt);
  524         }
m_freem(m);
  526         return;
  527 }
  529 /*
  530  * Neighbor advertisement input handling.
  531  *
  532  * Based on RFC 2461
  533  * Based on RFC 2462 (duplicated address detection)
  534  *
  535  * the following items are not implemented yet:
  536  * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
  537  * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
  538  */
  539 void
nd6_na_input(m, off, icmp6len)
  541         struct mbuf *m;
  542         int off, icmp6len;
  543 {
  544         struct ifnet *ifp = m->m_pkthdr.rcvif;
  545         struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
  546         struct nd_neighbor_advert *nd_na;
  547 #if 0
  548         struct in6_addr saddr6 = ip6->ip6_src;
  549 #endif
  550         struct in6_addr daddr6 = ip6->ip6_dst;
  551         struct in6_addr taddr6;
  552         int flags;
  553         int is_router;
  554         int is_solicited;
  555         int is_override;
  556         char *lladdr = NULL;
  557         int lladdrlen = 0;
  558         struct ifaddr *ifa;
  559         struct llinfo_nd6 *ln;
  560         struct rtentry *rt;
  561         struct sockaddr_dl *sdl;
  562         union nd_opts ndopts;
  564         if (ip6->ip6_hlim != 255) {
nd6log((LOG_ERR,
  566                     "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n",
ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src),
ip6_sprintf(&ip6->ip6_dst), ifp->if_xname));
  569                 goto bad;
  570         }
IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len);
  573         if (nd_na == NULL) {
icmp6stat.icp6s_tooshort++;
  575                 return;
  576         }
taddr6 = nd_na->nd_na_target;
flags = nd_na->nd_na_flags_reserved;
is_router = ((flags & ND_NA_FLAG_ROUTER) != 0);
is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0);
is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0);
  583         if (IN6_IS_SCOPE_EMBED(&taddr6))
taddr6.s6_addr16[1] = htons(ifp->if_index);
  586         if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
nd6log((LOG_ERR,
  588                     "nd6_na_input: invalid target address %s\n",
ip6_sprintf(&taddr6)));
  590                 goto bad;
  591         }
  592         if (is_solicited && IN6_IS_ADDR_MULTICAST(&daddr6)) {
nd6log((LOG_ERR,
  594                     "nd6_na_input: a solicited adv is multicasted\n"));
  595                 goto bad;
  596         }
icmp6len -= sizeof(*nd_na);
nd6_option_init(nd_na + 1, icmp6len, &ndopts);
  600         if (nd6_options(&ndopts) < 0) {
nd6log((LOG_INFO,
  602                     "nd6_na_input: invalid ND option, ignored\n"));
  603                 /* nd6_options have incremented stats */
  604                 goto freeit;
  605         }
  607         if (ndopts.nd_opts_tgt_lladdr) {
lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
  610         }
ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
  614         /*
  615          * Target address matches one of my interface address.
  616          *
  617          * If my address is tentative, this means that there's somebody
  618          * already using the same address as mine.  This indicates DAD failure.
  619          * This is defined in RFC 2462.
  620          *
  621          * Otherwise, process as defined in RFC 2461.
  622          */
  623         if (ifa
  624          && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) {
nd6_dad_na_input(ifa);
  626                 goto freeit;
  627         }
  629         /* Just for safety, maybe unnecessary. */
  630         if (ifa) {
log(LOG_ERR,
  632                     "nd6_na_input: duplicate IP6 address %s\n",
ip6_sprintf(&taddr6));
  634                 goto freeit;
  635         }
  637         if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s "
  639                     "(if %d, NA packet %d)\n", ip6_sprintf(&taddr6),
ifp->if_addrlen, lladdrlen - 2));
  641                 goto bad;
  642         }
  644         /*
  645          * If no neighbor cache entry is found, NA SHOULD silently be
  646          * discarded.
  647          */
rt = nd6_lookup(&taddr6, 0, ifp);
  649         if ((rt == NULL) ||
  650            ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) ||
  651            ((sdl = SDL(rt->rt_gateway)) == NULL))
  652                 goto freeit;
  654         if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
  655                 /*
  656                  * If the link-layer has address, and no lladdr option came,
  657                  * discard the packet.
  658                  */
  659                 if (ifp->if_addrlen && !lladdr)
  660                         goto freeit;
  662                 /*
  663                  * Record link-layer address, and update the state.
  664                  */
sdl->sdl_alen = ifp->if_addrlen;
bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
  667                 if (is_solicited) {
ln->ln_state = ND6_LLINFO_REACHABLE;
ln->ln_byhint = 0;
  670                         if (!ND6_LLINFO_PERMANENT(ln)) {
nd6_llinfo_settimer(ln,
  672                                     (long)ND_IFINFO(rt->rt_ifp)->reachable * hz);
  673                         }
  674                 } else {
ln->ln_state = ND6_LLINFO_STALE;
nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz);
  677                 }
  678                 if ((ln->ln_router = is_router) != 0) {
  679                         /*
  680                          * This means a router's state has changed from
  681                          * non-reachable to probably reachable, and might
  682                          * affect the status of associated prefixes..
  683                          */
pfxlist_onlink_check();
  685                 }
  686         } else {
  687                 int llchange;
  689                 /*
  690                  * Check if the link-layer address has changed or not.
  691                  */
  692                 if (!lladdr)
llchange = 0;
  694                 else {
  695                         if (sdl->sdl_alen) {
  696                                 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen))
llchange = 1;
  698                                 else
llchange = 0;
  700                         } else
llchange = 1;
  702                 }
  704                 /*
  705                  * This is VERY complex.  Look at it with care.
  706                  *
  707                  * override solicit lladdr llchange     action
  708                  *                                      (L: record lladdr)
  709                  *
  710                  *      0       0       n       --      (2c)
  711                  *      0       0       y       n       (2b) L
  712                  *      0       0       y       y       (1)    REACHABLE->STALE
  713                  *      0       1       n       --      (2c)   *->REACHABLE
  714                  *      0       1       y       n       (2b) L *->REACHABLE
  715                  *      0       1       y       y       (1)    REACHABLE->STALE
  716                  *      1       0       n       --      (2a)
  717                  *      1       0       y       n       (2a) L
  718                  *      1       0       y       y       (2a) L *->STALE
  719                  *      1       1       n       --      (2a)   *->REACHABLE
  720                  *      1       1       y       n       (2a) L *->REACHABLE
  721                  *      1       1       y       y       (2a) L *->REACHABLE
  722                  */
  723                 if (!is_override && (lladdr && llchange)) {        /* (1) */
  724                         /*
  725                          * If state is REACHABLE, make it STALE.
  726                          * no other updates should be done.
  727                          */
  728                         if (ln->ln_state == ND6_LLINFO_REACHABLE) {
ln->ln_state = ND6_LLINFO_STALE;
nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz);
  731                         }
  732                         goto freeit;
  733                 } else if (is_override                             /* (2a) */
  734                         || (!is_override && (lladdr && !llchange)) /* (2b) */
  735                         || !lladdr) {                              /* (2c) */
  736                         /*
  737                          * Update link-local address, if any.
  738                          */
  739                         if (lladdr) {
sdl->sdl_alen = ifp->if_addrlen;
bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
  742                         }
  744                         /*
  745                          * If solicited, make the state REACHABLE.
  746                          * If not solicited and the link-layer address was
  747                          * changed, make it STALE.
  748                          */
  749                         if (is_solicited) {
ln->ln_state = ND6_LLINFO_REACHABLE;
ln->ln_byhint = 0;
  752                                 if (!ND6_LLINFO_PERMANENT(ln)) {
nd6_llinfo_settimer(ln,
  754                                             (long)ND_IFINFO(ifp)->reachable * hz);
  755                                 }
  756                         } else {
  757                                 if (lladdr && llchange) {
ln->ln_state = ND6_LLINFO_STALE;
nd6_llinfo_settimer(ln,
  760                                             (long)nd6_gctimer * hz);
  761                                 }
  762                         }
  763                 }
  765                 if (ln->ln_router && !is_router) {
  766                         /*
  767                          * The peer dropped the router flag.
  768                          * Remove the sender from the Default Router List and
  769                          * update the Destination Cache entries.
  770                          */
  771                         struct nd_defrouter *dr;
  772                         struct in6_addr *in6;
  773                         int s;
in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr;
  777                         /*
  778                          * Lock to protect the default router list.
  779                          * XXX: this might be unnecessary, since this function
  780                          * is only called under the network software interrupt
  781                          * context.  However, we keep it just for safety.
  782                          */
s = splsoftnet();
dr = defrouter_lookup(in6, rt->rt_ifp);
  785                         if (dr)
defrtrlist_del(dr);
  787                         else if (!ip6_forwarding) {
  788                                 /*
  789                                  * Even if the neighbor is not in the default
  790                                  * router list, the neighbor may be used
  791                                  * as a next hop for some destinations
  792                                  * (e.g. redirect case). So we must
  793                                  * call rt6_flush explicitly.
  794                                  */
rt6_flush(&ip6->ip6_src, rt->rt_ifp);
  796                         }
splx(s);
  798                 }
ln->ln_router = is_router;
  800         }
rt->rt_flags &= ~RTF_REJECT;
ln->ln_asked = 0;
  803         if (ln->ln_hold) {
  804                 /*
  805                  * we assume ifp is not a loopback here, so just set the 2nd
  806                  * argument as the 1st one.
  807                  */
nd6_output(ifp, ifp, ln->ln_hold,
  809                            (struct sockaddr_in6 *)rt_key(rt), rt);
ln->ln_hold = NULL;
  811         }
freeit:
m_freem(m);
  815         return;
bad:
icmp6stat.icp6s_badna++;
m_freem(m);
  820 }
  822 /*
  823  * Neighbor advertisement output handling.
  824  *
  825  * Based on RFC 2461
  826  *
  827  * the following items are not implemented yet:
  828  * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
  829  * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
  830  */
  831 void
nd6_na_output(ifp, daddr6, taddr6, flags, tlladdr, sdl0)
  833         struct ifnet *ifp;
  834         struct in6_addr *daddr6, *taddr6;
u_long flags;
  836         int tlladdr;            /* 1 if include target link-layer address */
  837         struct sockaddr *sdl0;  /* sockaddr_dl (= proxy NA) or NULL */
  838 {
  839         struct mbuf *m;
  840         struct ip6_hdr *ip6;
  841         struct nd_neighbor_advert *nd_na;
  842         struct ip6_moptions im6o;
  843         struct sockaddr_in6 src_sa, dst_sa;
  844         struct in6_addr *src0;
  845         int icmp6len, maxlen, error;
caddr_t mac;
  847         struct route_in6 ro;
mac = NULL;
bzero(&ro, sizeof(ro));
  852         /* estimate the size of message */
maxlen = sizeof(*ip6) + sizeof(*nd_na);
maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
  855 #ifdef DIAGNOSTIC
  856         if (max_linkhdr + maxlen >= MCLBYTES) {
printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES "
  858                     "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
panic("nd6_na_output: insufficient MCLBYTES");
  860                 /* NOTREACHED */
  861         }
  862 #endif
MGETHDR(m, M_DONTWAIT, MT_DATA);
  865         if (m && max_linkhdr + maxlen >= MHLEN) {
MCLGET(m, M_DONTWAIT);
  867                 if ((m->m_flags & M_EXT) == 0) {
m_free(m);
m = NULL;
  870                 }
  871         }
  872         if (m == NULL)
  873                 return;
m->m_pkthdr.rcvif = NULL;
  876         if (IN6_IS_ADDR_MULTICAST(daddr6)) {
m->m_flags |= M_MCAST;
im6o.im6o_multicast_ifp = ifp;
im6o.im6o_multicast_hlim = 255;
im6o.im6o_multicast_loop = 0;
  881         }
icmp6len = sizeof(*nd_na);
m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len;
m->m_data += max_linkhdr;       /* or MH_ALIGN() equivalent? */
  887         /* fill neighbor advertisement packet */
ip6 = mtod(m, struct ip6_hdr *);
ip6->ip6_flow = 0;
ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
ip6->ip6_vfc |= IPV6_VERSION;
ip6->ip6_nxt = IPPROTO_ICMPV6;
ip6->ip6_hlim = 255;
bzero(&src_sa, sizeof(src_sa));
bzero(&dst_sa, sizeof(dst_sa));
src_sa.sin6_len = dst_sa.sin6_len = sizeof(struct sockaddr_in6);
src_sa.sin6_family = dst_sa.sin6_family = AF_INET6;
dst_sa.sin6_addr = *daddr6;
  899         if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) {
  900                 /* reply to DAD */
dst_sa.sin6_addr.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
dst_sa.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
dst_sa.sin6_addr.s6_addr32[1] = 0;
dst_sa.sin6_addr.s6_addr32[2] = 0;
dst_sa.sin6_addr.s6_addr32[3] = IPV6_ADDR_INT32_ONE;
flags &= ~ND_NA_FLAG_SOLICITED;
  908         }
ip6->ip6_dst = dst_sa.sin6_addr;
  911         /*
  912          * Select a source whose scope is the same as that of the dest.
  913          */
bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa));
src0 = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &error);
  916         if (src0 == NULL) {
nd6log((LOG_DEBUG, "nd6_na_output: source can't be "
  918                     "determined: dst=%s, error=%d\n",
ip6_sprintf(&dst_sa.sin6_addr), error));
  920                 goto bad;
  921         }
src_sa.sin6_addr = *src0;
ip6->ip6_src = src_sa.sin6_addr;
nd_na = (struct nd_neighbor_advert *)(ip6 + 1);
nd_na->nd_na_type = ND_NEIGHBOR_ADVERT;
nd_na->nd_na_code = 0;
nd_na->nd_na_target = *taddr6;
  928         if (IN6_IS_SCOPE_EMBED(&nd_na->nd_na_target))
nd_na->nd_na_target.s6_addr16[1] = 0;
  931         /*
  932          * "tlladdr" indicates NS's condition for adding tlladdr or not.
  933          * see nd6_ns_input() for details.
  934          * Basically, if NS packet is sent to unicast/anycast addr,
  935          * target lladdr option SHOULD NOT be included.
  936          */
  937         if (tlladdr) {
  938                 /*
  939                  * sdl0 != NULL indicates proxy NA.  If we do proxy, use
  940                  * lladdr in sdl0.  If we are not proxying (sending NA for
  941                  * my address) use lladdr configured for the interface.
  942                  */
  943                 if (sdl0 == NULL) {
mac = nd6_ifptomac(ifp);
  945                 } else if (sdl0->sa_family == AF_LINK) {
  946                         struct sockaddr_dl *sdl;
sdl = (struct sockaddr_dl *)sdl0;
  948                         if (sdl->sdl_alen == ifp->if_addrlen)
mac = LLADDR(sdl);
  950                 }
  951         }
  952         if (tlladdr && mac) {
  953                 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
  954                 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1);
  956                 /* roundup to 8 bytes alignment! */
optlen = (optlen + 7) & ~7;
m->m_pkthdr.len += optlen;
m->m_len += optlen;
icmp6len += optlen;
bzero((caddr_t)nd_opt, optlen);
nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
nd_opt->nd_opt_len = optlen >> 3;
bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
  966         } else
flags &= ~ND_NA_FLAG_OVERRIDE;
ip6->ip6_plen = htons((u_short)icmp6len);
nd_na->nd_na_flags_reserved = flags;
nd_na->nd_na_cksum = 0;
nd_na->nd_na_cksum =
in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len);
ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL);
icmp6_ifstat_inc(ifp, ifs6_out_msg);
icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert);
icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++;
  981         if (ro.ro_rt) {         /* we don't cache this route. */
RTFREE(ro.ro_rt);
  983         }
  984         return;
bad:
  987         if (ro.ro_rt) {
RTFREE(ro.ro_rt);
  989         }
m_freem(m);
  991         return;
  992 }
caddr_t
nd6_ifptomac(ifp)
  996         struct ifnet *ifp;
  997 {
  998         switch (ifp->if_type) {
  999         case IFT_ETHER:
 1000         case IFT_FDDI:
 1001         case IFT_IEEE1394:
 1002         case IFT_PROPVIRTUAL:
 1003         case IFT_CARP:
 1004         case IFT_L2VLAN:
 1005         case IFT_IEEE80211:
 1006                 return ((caddr_t)(ifp + 1));
 1007         default:
 1008                 return NULL;
 1009         }
 1010 }
TAILQ_HEAD(dadq_head, dadq);
 1013 struct dadq {
TAILQ_ENTRY(dadq) dad_list;
 1015         struct ifaddr *dad_ifa;
 1016         int dad_count;          /* max NS to send */
 1017         int dad_ns_tcount;      /* # of trials to send NS */
 1018         int dad_ns_ocount;      /* NS sent so far */
 1019         int dad_ns_icount;
 1020         int dad_na_icount;
 1021         struct timeout dad_timer_ch;
 1022 };
 1024 static struct dadq_head dadq;
 1025 static int dad_init = 0;
 1027 static struct dadq *
nd6_dad_find(ifa)
 1029         struct ifaddr *ifa;
 1030 {
 1031         struct dadq *dp;
TAILQ_FOREACH(dp, &dadq, dad_list) {
 1034                 if (dp->dad_ifa == ifa)
 1035                         return dp;
 1036         }
 1037         return NULL;
 1038 }
 1040 static void
nd6_dad_starttimer(dp, ticks)
 1042         struct dadq *dp;
 1043         int ticks;
 1044 {
timeout_set(&dp->dad_timer_ch, (void (*)(void *))nd6_dad_timer,
 1047             (void *)dp->dad_ifa);
timeout_add(&dp->dad_timer_ch, ticks);
 1049 }
 1051 static void
nd6_dad_stoptimer(dp)
 1053         struct dadq *dp;
 1054 {
timeout_del(&dp->dad_timer_ch);
 1057 }
 1059 /*
 1060  * Start Duplicated Address Detection (DAD) for specified interface address.
 1061  */
 1062 void
nd6_dad_start(ifa, tick)
 1064         struct ifaddr *ifa;
 1065         int *tick;      /* minimum delay ticks for IFF_UP event */
 1066 {
 1067         struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
 1068         struct dadq *dp;
 1070         if (!dad_init) {
TAILQ_INIT(&dadq);
dad_init++;
 1073         }
 1075         /*
 1076          * If we don't need DAD, don't do it.
 1077          * There are several cases:
 1078          * - DAD is disabled (ip6_dad_count == 0)
 1079          * - the interface address is anycast
 1080          */
 1081         if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
log(LOG_DEBUG,
 1083                         "nd6_dad_start: called with non-tentative address "
 1084                         "%s(%s)\n",
ip6_sprintf(&ia->ia_addr.sin6_addr),
ifa->ifa_ifp ? ifa->ifa_ifp->if_xname : "???");
 1087                 return;
 1088         }
 1089         if (ia->ia6_flags & IN6_IFF_ANYCAST) {
ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
 1091                 return;
 1092         }
 1093         if (!ip6_dad_count) {
ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
 1095                 return;
 1096         }
 1097         if (!ifa->ifa_ifp)
panic("nd6_dad_start: ifa->ifa_ifp == NULL");
 1099         if (!(ifa->ifa_ifp->if_flags & IFF_UP))
 1100                 return;
 1101         if (nd6_dad_find(ifa) != NULL) {
 1102                 /* DAD already in progress */
 1103                 return;
 1104         }
dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT);
 1107         if (dp == NULL) {
log(LOG_ERR, "nd6_dad_start: memory allocation failed for "
 1109                         "%s(%s)\n",
ip6_sprintf(&ia->ia_addr.sin6_addr),
ifa->ifa_ifp ? ifa->ifa_ifp->if_xname : "???");
 1112                 return;
 1113         }
bzero(dp, sizeof(*dp));
bzero(&dp->dad_timer_ch, sizeof(dp->dad_timer_ch));
TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list);
nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", ifa->ifa_ifp->if_xname,
ip6_sprintf(&ia->ia_addr.sin6_addr)));
 1121         /*
 1122          * Send NS packet for DAD, ip6_dad_count times.
 1123          * Note that we must delay the first transmission, if this is the
 1124          * first packet to be sent from the interface after interface
 1125          * (re)initialization.
 1126          */
dp->dad_ifa = ifa;
ifa->ifa_refcnt++;      /* just for safety */
dp->dad_count = ip6_dad_count;
dp->dad_ns_icount = dp->dad_na_icount = 0;
dp->dad_ns_ocount = dp->dad_ns_tcount = 0;
 1132         if (tick == NULL) {
nd6_dad_ns_output(dp, ifa);
nd6_dad_starttimer(dp,
 1135                     (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
 1136         } else {
 1137                 int ntick;
 1139                 if (*tick == 0)
ntick = arc4random() % (MAX_RTR_SOLICITATION_DELAY * hz);
 1141                 else
ntick = *tick + arc4random() % (hz / 2);
 1143                 *tick = ntick;
nd6_dad_starttimer(dp, ntick);
 1145         }
 1146 }
 1148 /*
 1149  * terminate DAD unconditionally.  used for address removals.
 1150  */
 1151 void
nd6_dad_stop(ifa)
 1153         struct ifaddr *ifa;
 1154 {
 1155         struct dadq *dp;
 1157         if (!dad_init)
 1158                 return;
dp = nd6_dad_find(ifa);
 1160         if (!dp) {
 1161                 /* DAD wasn't started yet */
 1162                 return;
 1163         }
nd6_dad_stoptimer(dp);
TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
free(dp, M_IP6NDP);
dp = NULL;
IFAFREE(ifa);
 1171 }
 1173 static void
nd6_dad_timer(ifa)
 1175         struct ifaddr *ifa;
 1176 {
 1177         int s;
 1178         struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
 1179         struct dadq *dp;
s = splsoftnet();               /* XXX */
 1183         /* Sanity check */
 1184         if (ia == NULL) {
log(LOG_ERR, "nd6_dad_timer: called with null parameter\n");
 1186                 goto done;
 1187         }
dp = nd6_dad_find(ifa);
 1189         if (dp == NULL) {
log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n");
 1191                 goto done;
 1192         }
 1193         if (ia->ia6_flags & IN6_IFF_DUPLICATED) {
log(LOG_ERR, "nd6_dad_timer: called with duplicated address "
 1195                         "%s(%s)\n",
ip6_sprintf(&ia->ia_addr.sin6_addr),
ifa->ifa_ifp ? ifa->ifa_ifp->if_xname : "???");
 1198                 goto done;
 1199         }
 1200         if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) {
log(LOG_ERR, "nd6_dad_timer: called with non-tentative address "
 1202                         "%s(%s)\n",
ip6_sprintf(&ia->ia_addr.sin6_addr),
ifa->ifa_ifp ? ifa->ifa_ifp->if_xname : "???");
 1205                 goto done;
 1206         }
 1208         /* timeouted with IFF_{RUNNING,UP} check */
 1209         if (dp->dad_ns_tcount > dad_maxtry) {
nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n",
ifa->ifa_ifp->if_xname));
TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
free(dp, M_IP6NDP);
dp = NULL;
IFAFREE(ifa);
 1217                 goto done;
 1218         }
 1220         /* Need more checks? */
 1221         if (dp->dad_ns_ocount < dp->dad_count) {
 1222                 /*
 1223                  * We have more NS to go.  Send NS packet for DAD.
 1224                  */
nd6_dad_ns_output(dp, ifa);
nd6_dad_starttimer(dp,
 1227                     (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
 1228         } else {
 1229                 /*
 1230                  * We have transmitted sufficient number of DAD packets.
 1231                  * See what we've got.
 1232                  */
 1233                 int duplicate;
duplicate = 0;
 1237                 if (dp->dad_na_icount) {
 1238                         /*
 1239                          * the check is in nd6_dad_na_input(),
 1240                          * but just in case
 1241                          */
duplicate++;
 1243                 }
 1245                 if (dp->dad_ns_icount) {
 1246                         /* We've seen NS, means DAD has failed. */
duplicate++;
 1248                 }
 1250                 if (duplicate) {
 1251                         /* (*dp) will be freed in nd6_dad_duplicated() */
dp = NULL;
nd6_dad_duplicated(ifa);
 1254                 } else {
 1255                         /*
 1256                          * We are done with DAD.  No NA came, no NS came.
 1257                          * duplicated address found.
 1258                          */
ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
nd6log((LOG_DEBUG,
 1262                             "%s: DAD complete for %s - no duplicates found\n",
ifa->ifa_ifp->if_xname,
ip6_sprintf(&ia->ia_addr.sin6_addr)));
TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
free(dp, M_IP6NDP);
dp = NULL;
IFAFREE(ifa);
 1270                 }
 1271         }
done:
splx(s);
 1275 }
 1277 void
nd6_dad_duplicated(ifa)
 1279         struct ifaddr *ifa;
 1280 {
 1281         struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
 1282         struct dadq *dp;
dp = nd6_dad_find(ifa);
 1285         if (dp == NULL) {
log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n");
 1287                 return;
 1288         }
log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: "
 1291             "NS in/out=%d/%d, NA in=%d\n",
ifa->ifa_ifp->if_xname, ip6_sprintf(&ia->ia_addr.sin6_addr),
dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount);
ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
ia->ia6_flags |= IN6_IFF_DUPLICATED;
 1298         /* We are done with DAD, with duplicated address found. (failure) */
nd6_dad_stoptimer(dp);
log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n",
ifa->ifa_ifp->if_xname, ip6_sprintf(&ia->ia_addr.sin6_addr));
log(LOG_ERR, "%s: manual intervention required\n",
ifa->ifa_ifp->if_xname);
TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
free(dp, M_IP6NDP);
dp = NULL;
IFAFREE(ifa);
 1310 }
 1312 static void
nd6_dad_ns_output(dp, ifa)
 1314         struct dadq *dp;
 1315         struct ifaddr *ifa;
 1316 {
 1317         struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
 1318         struct ifnet *ifp = ifa->ifa_ifp;
dp->dad_ns_tcount++;
 1321         if ((ifp->if_flags & IFF_UP) == 0) {
 1322 #if 0
printf("%s: interface down?\n", ifp->if_xname);
 1324 #endif
 1325                 return;
 1326         }
 1327         if ((ifp->if_flags & IFF_RUNNING) == 0) {
 1328 #if 0
printf("%s: interface not running?\n", ifp->if_xname);
 1330 #endif
 1331                 return;
 1332         }
dp->dad_ns_ocount++;
nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1);
 1336 }
 1338 static void
nd6_dad_ns_input(ifa)
 1340         struct ifaddr *ifa;
 1341 {
 1342         struct in6_ifaddr *ia;
 1343         struct ifnet *ifp;
 1344         struct in6_addr *taddr6;
 1345         struct dadq *dp;
 1346         int duplicate;
 1348         if (!ifa)
panic("ifa == NULL in nd6_dad_ns_input");
ia = (struct in6_ifaddr *)ifa;
ifp = ifa->ifa_ifp;
taddr6 = &ia->ia_addr.sin6_addr;
duplicate = 0;
dp = nd6_dad_find(ifa);
 1357         /* Quickhack - completely ignore DAD NS packets */
 1358         if (dad_ignore_ns) {
nd6log((LOG_INFO,
 1360                     "nd6_dad_ns_input: ignoring DAD NS packet for "
 1361                     "address %s(%s)\n", ip6_sprintf(taddr6),
ifa->ifa_ifp->if_xname));
 1363                 return;
 1364         }
 1366         /*
 1367          * if I'm yet to start DAD, someone else started using this address
 1368          * first.  I have a duplicate and you win.
 1369          */
 1370         if (!dp || dp->dad_ns_ocount == 0)
duplicate++;
 1373         /* XXX more checks for loopback situation - see nd6_dad_timer too */
 1375         if (duplicate) {
dp = NULL;      /* will be freed in nd6_dad_duplicated() */
nd6_dad_duplicated(ifa);
 1378         } else {
 1379                 /*
 1380                  * not sure if I got a duplicate.
 1381                  * increment ns count and see what happens.
 1382                  */
 1383                 if (dp)
dp->dad_ns_icount++;
 1385         }
 1386 }
 1388 static void
nd6_dad_na_input(ifa)
 1390         struct ifaddr *ifa;
 1391 {
 1392         struct dadq *dp;
 1394         if (!ifa)
panic("ifa == NULL in nd6_dad_na_input");
dp = nd6_dad_find(ifa);
 1398         if (dp)
dp->dad_na_icount++;
 1401         /* remove the address. */
nd6_dad_duplicated(ifa);
 1403 }