2 /* $KAME: nd6_nbr.c,v 1.86 2002/01/21 02:33:04 jinmei Exp $ */
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
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.
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
34 #include "opt_inet6.h"
35 #include "opt_ipsec.h"
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/malloc.h>
42 #include <sys/socket.h>
43 #include <sys/sockio.h>
45 #include <sys/kernel.h>
46 #include <sys/errno.h>
47 #include <sys/syslog.h>
48 #include <sys/queue.h>
49 #include <sys/callout.h>
52 #include <net/if_types.h>
53 #include <net/if_dl.h>
54 #include <net/if_var.h>
55 #include <net/route.h>
57 #include <netinet/in.h>
58 #include <netinet/in_var.h>
59 #include <netinet6/in6_var.h>
60 #include <netinet6/in6_ifattach.h>
61 #include <netinet/ip6.h>
62 #include <netinet6/ip6_var.h>
63 #include <netinet6/scope6_var.h>
64 #include <netinet6/nd6.h>
65 #include <netinet/icmp6.h>
68 #include <netinet/ip_carp.h>
71 #define SDL(s) ((struct sockaddr_dl *)s)
74 static struct dadq *nd6_dad_find __P((struct ifaddr *));
75 static void nd6_dad_starttimer __P((struct dadq *, int));
76 static void nd6_dad_stoptimer __P((struct dadq *));
77 static void nd6_dad_timer __P((struct ifaddr *));
78 static void nd6_dad_ns_output __P((struct dadq *, struct ifaddr *));
79 static void nd6_dad_ns_input __P((struct ifaddr *));
80 static void nd6_dad_na_input __P((struct ifaddr *));
82 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/
83 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */
86 * Input a Neighbor Solicitation Message.
89 * Based on RFC 2462 (duplicate address detection)
92 nd6_ns_input(m, off, icmp6len)
96 struct ifnet *ifp = m->m_pkthdr.rcvif;
97 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
98 struct nd_neighbor_solicit *nd_ns;
99 struct in6_addr saddr6 = ip6->ip6_src;
100 struct in6_addr daddr6 = ip6->ip6_dst;
101 struct in6_addr taddr6;
102 struct in6_addr myaddr6;
104 struct ifaddr *ifa = NULL;
106 int anycast = 0, proxy = 0, tentative = 0;
108 union nd_opts ndopts;
109 struct sockaddr_dl *proxydl = NULL;
110 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
112 #ifndef PULLDOWN_TEST
113 IP6_EXTHDR_CHECK(m, off, icmp6len,);
114 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off);
116 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len);
118 icmp6stat.icp6s_tooshort++;
122 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */
123 taddr6 = nd_ns->nd_ns_target;
124 if (in6_setscope(&taddr6, ifp, NULL) != 0)
127 if (ip6->ip6_hlim != 255) {
129 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n",
130 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
131 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
135 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
136 /* dst has to be a solicited node multicast address. */
137 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL &&
138 /* don't check ifindex portion */
139 daddr6.s6_addr32[1] == 0 &&
140 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE &&
141 daddr6.s6_addr8[12] == 0xff) {
144 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
145 "(wrong ip6 dst)\n"));
150 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
151 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n"));
155 icmp6len -= sizeof(*nd_ns);
156 nd6_option_init(nd_ns + 1, icmp6len, &ndopts);
157 if (nd6_options(&ndopts) < 0) {
159 "nd6_ns_input: invalid ND option, ignored\n"));
160 /* nd6_options have incremented stats */
164 if (ndopts.nd_opts_src_lladdr) {
165 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
166 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
169 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) {
170 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
171 "(link-layer address option)\n"));
176 * Attaching target link-layer address to the NA?
179 * NS IP dst is unicast/anycast MUST NOT add
180 * NS IP dst is solicited-node multicast MUST add
182 * In implementation, we add target link-layer address by default.
183 * We do not add one in MUST NOT cases.
185 if (!IN6_IS_ADDR_MULTICAST(&daddr6))
191 * Target address (taddr6) must be either:
192 * (1) Valid unicast/anycast address for my receiving interface,
193 * (2) Unicast address for which I'm offering proxy service, or
194 * (3) "tentative" address on which DAD is being performed.
196 /* (1) and (3) check. */
199 ifa = carp_iamatch6(ifp->if_carp, &taddr6);
201 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
203 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
209 struct sockaddr_in6 tsin6;
212 bzero(&tsin6, sizeof tsin6);
213 tsin6.sin6_len = sizeof(struct sockaddr_in6);
214 tsin6.sin6_family = AF_INET6;
215 tsin6.sin6_addr = taddr6;
217 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0);
218 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 &&
219 rt->rt_gateway->sa_family == AF_LINK);
224 * proxy NDP for single entry
226 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp,
227 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
230 proxydl = SDL(rt->rt_gateway);
236 * We've got an NS packet, and we don't have that adddress
237 * assigned for us. We MUST silently ignore it.
242 myaddr6 = *IFA_IN6(ifa);
243 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST;
244 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE;
245 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED)
248 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
249 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s "
250 "(if %d, NS packet %d)\n",
251 ip6_sprintf(ip6bufs, &taddr6),
252 ifp->if_addrlen, lladdrlen - 2));
256 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) {
257 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n",
258 ip6_sprintf(ip6bufs, &saddr6)));
263 * We have neighbor solicitation packet, with target address equals to
264 * one of my tentative address.
266 * src addr how to process?
268 * multicast of course, invalid (rejected in ip6_input)
269 * unicast somebody is doing address resolution -> ignore
270 * unspec dup address detection
272 * The processing is defined in RFC 2462.
276 * If source address is unspecified address, it is for
277 * duplicate address detection.
279 * If not, the packet is for addess resolution;
280 * silently ignore it.
282 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6))
283 nd6_dad_ns_input(ifa);
289 * If the source address is unspecified address, entries must not
290 * be created or updated.
291 * It looks that sender is performing DAD. Output NA toward
292 * all-node multicast address, to tell the sender that I'm using
294 * S bit ("solicited") must be zero.
296 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
297 struct in6_addr in6_all;
299 in6_all = in6addr_linklocal_allnodes;
300 if (in6_setscope(&in6_all, ifp, NULL) != 0)
302 nd6_na_output(ifp, &in6_all, &taddr6,
303 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
304 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0),
305 tlladdr, (struct sockaddr *)proxydl);
309 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen,
310 ND_NEIGHBOR_SOLICIT, 0);
312 nd6_na_output(ifp, &saddr6, &taddr6,
313 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
314 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED,
315 tlladdr, (struct sockaddr *)proxydl);
321 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n",
322 ip6_sprintf(ip6bufs, &saddr6)));
323 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n",
324 ip6_sprintf(ip6bufs, &daddr6)));
325 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n",
326 ip6_sprintf(ip6bufs, &taddr6)));
327 icmp6stat.icp6s_badns++;
332 * Output a Neighbor Solicitation Message. Caller specifies:
333 * - ICMP6 header source IP6 address
334 * - ND6 header target IP6 address
335 * - ND6 header source datalink address
338 * Based on RFC 2462 (duplicate address detection)
341 nd6_ns_output(ifp, daddr6, taddr6, ln, dad)
343 const struct in6_addr *daddr6, *taddr6;
344 struct llinfo_nd6 *ln; /* for source address determination */
345 int dad; /* duplicate address detection */
349 struct nd_neighbor_solicit *nd_ns;
350 struct in6_addr *src, src_in;
351 struct ip6_moptions im6o;
357 bzero(&ro, sizeof(ro));
359 if (IN6_IS_ADDR_MULTICAST(taddr6))
362 /* estimate the size of message */
363 maxlen = sizeof(*ip6) + sizeof(*nd_ns);
364 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
365 if (max_linkhdr + maxlen >= MCLBYTES) {
367 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES "
368 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
373 MGETHDR(m, M_DONTWAIT, MT_DATA);
374 if (m && max_linkhdr + maxlen >= MHLEN) {
375 MCLGET(m, M_DONTWAIT);
376 if ((m->m_flags & M_EXT) == 0) {
383 m->m_pkthdr.rcvif = NULL;
385 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) {
386 m->m_flags |= M_MCAST;
387 im6o.im6o_multicast_ifp = ifp;
388 im6o.im6o_multicast_hlim = 255;
389 im6o.im6o_multicast_loop = 0;
392 icmp6len = sizeof(*nd_ns);
393 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len;
394 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
396 /* fill neighbor solicitation packet */
397 ip6 = mtod(m, struct ip6_hdr *);
399 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
400 ip6->ip6_vfc |= IPV6_VERSION;
401 /* ip6->ip6_plen will be set later */
402 ip6->ip6_nxt = IPPROTO_ICMPV6;
405 ip6->ip6_dst = *daddr6;
407 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
408 ip6->ip6_dst.s6_addr16[1] = 0;
409 ip6->ip6_dst.s6_addr32[1] = 0;
410 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE;
411 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3];
412 ip6->ip6_dst.s6_addr8[12] = 0xff;
413 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0)
419 * "If the source address of the packet prompting the
420 * solicitation is the same as one of the addresses assigned
421 * to the outgoing interface, that address SHOULD be placed
422 * in the IP Source Address of the outgoing solicitation.
423 * Otherwise, any one of the addresses assigned to the
424 * interface should be used."
426 * We use the source address for the prompting packet
428 * - saddr6 is given from the caller (by giving "ln"), and
429 * - saddr6 belongs to the outgoing interface.
430 * Otherwise, we perform the source address selection as usual.
432 struct ip6_hdr *hip6; /* hold ip6 */
433 struct in6_addr *hsrc = NULL;
435 if (ln && ln->ln_hold) {
437 * assuming every packet in ln_hold has the same IP
440 hip6 = mtod(ln->ln_hold, struct ip6_hdr *);
442 if (sizeof(*hip6) < ln->ln_hold->m_len)
443 hsrc = &hip6->ip6_src;
447 if (hsrc && in6ifa_ifpwithaddr(ifp, hsrc))
451 struct sockaddr_in6 dst_sa;
453 bzero(&dst_sa, sizeof(dst_sa));
454 dst_sa.sin6_family = AF_INET6;
455 dst_sa.sin6_len = sizeof(dst_sa);
456 dst_sa.sin6_addr = ip6->ip6_dst;
458 src = in6_selectsrc(&dst_sa, NULL,
459 NULL, &ro, NULL, NULL, &error);
461 char ip6buf[INET6_ADDRSTRLEN];
463 "nd6_ns_output: source can't be "
464 "determined: dst=%s, error=%d\n",
465 ip6_sprintf(ip6buf, &dst_sa.sin6_addr),
472 * Source address for DAD packet must always be IPv6
473 * unspecified address. (0::0)
474 * We actually don't have to 0-clear the address (we did it
475 * above), but we do so here explicitly to make the intention
478 bzero(&src_in, sizeof(src_in));
482 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1);
483 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT;
484 nd_ns->nd_ns_code = 0;
485 nd_ns->nd_ns_reserved = 0;
486 nd_ns->nd_ns_target = *taddr6;
487 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */
490 * Add source link-layer address option.
492 * spec implementation
494 * DAD packet MUST NOT do not add the option
495 * there's no link layer address:
496 * impossible do not add the option
497 * there's link layer address:
498 * Multicast NS MUST add one add the option
499 * Unicast NS SHOULD add one add the option
501 if (!dad && (mac = nd6_ifptomac(ifp))) {
502 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
503 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
504 /* 8 byte alignments... */
505 optlen = (optlen + 7) & ~7;
507 m->m_pkthdr.len += optlen;
510 bzero((caddr_t)nd_opt, optlen);
511 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR;
512 nd_opt->nd_opt_len = optlen >> 3;
513 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
516 ip6->ip6_plen = htons((u_short)icmp6len);
517 nd_ns->nd_ns_cksum = 0;
519 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len);
521 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL);
522 icmp6_ifstat_inc(ifp, ifs6_out_msg);
523 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit);
524 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++;
526 if (ro.ro_rt) { /* we don't cache this route. */
540 * Neighbor advertisement input handling.
543 * Based on RFC 2462 (duplicate address detection)
545 * the following items are not implemented yet:
546 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
547 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
550 nd6_na_input(m, off, icmp6len)
554 struct ifnet *ifp = m->m_pkthdr.rcvif;
555 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
556 struct nd_neighbor_advert *nd_na;
557 struct in6_addr daddr6 = ip6->ip6_dst;
558 struct in6_addr taddr6;
566 struct llinfo_nd6 *ln;
568 struct sockaddr_dl *sdl;
569 union nd_opts ndopts;
570 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
572 if (ip6->ip6_hlim != 255) {
574 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n",
575 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
576 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
580 #ifndef PULLDOWN_TEST
581 IP6_EXTHDR_CHECK(m, off, icmp6len,);
582 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off);
584 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len);
586 icmp6stat.icp6s_tooshort++;
591 flags = nd_na->nd_na_flags_reserved;
592 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0);
593 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0);
594 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0);
596 taddr6 = nd_na->nd_na_target;
597 if (in6_setscope(&taddr6, ifp, NULL))
598 goto bad; /* XXX: impossible */
600 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
602 "nd6_na_input: invalid target address %s\n",
603 ip6_sprintf(ip6bufs, &taddr6)));
606 if (IN6_IS_ADDR_MULTICAST(&daddr6))
609 "nd6_na_input: a solicited adv is multicasted\n"));
613 icmp6len -= sizeof(*nd_na);
614 nd6_option_init(nd_na + 1, icmp6len, &ndopts);
615 if (nd6_options(&ndopts) < 0) {
617 "nd6_na_input: invalid ND option, ignored\n"));
618 /* nd6_options have incremented stats */
622 if (ndopts.nd_opts_tgt_lladdr) {
623 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
624 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
627 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
630 * Target address matches one of my interface address.
632 * If my address is tentative, this means that there's somebody
633 * already using the same address as mine. This indicates DAD failure.
634 * This is defined in RFC 2462.
636 * Otherwise, process as defined in RFC 2461.
639 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) {
640 nd6_dad_na_input(ifa);
644 /* Just for safety, maybe unnecessary. */
647 "nd6_na_input: duplicate IP6 address %s\n",
648 ip6_sprintf(ip6bufs, &taddr6));
652 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
653 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s "
654 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6),
655 ifp->if_addrlen, lladdrlen - 2));
660 * If no neighbor cache entry is found, NA SHOULD silently be
663 rt = nd6_lookup(&taddr6, 0, ifp);
665 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) ||
666 ((sdl = SDL(rt->rt_gateway)) == NULL))
669 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
671 * If the link-layer has address, and no lladdr option came,
672 * discard the packet.
674 if (ifp->if_addrlen && lladdr == NULL)
678 * Record link-layer address, and update the state.
680 sdl->sdl_alen = ifp->if_addrlen;
681 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
683 ln->ln_state = ND6_LLINFO_REACHABLE;
685 if (!ND6_LLINFO_PERMANENT(ln)) {
686 nd6_llinfo_settimer(ln,
687 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz);
690 ln->ln_state = ND6_LLINFO_STALE;
691 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz);
693 if ((ln->ln_router = is_router) != 0) {
695 * This means a router's state has changed from
696 * non-reachable to probably reachable, and might
697 * affect the status of associated prefixes..
699 pfxlist_onlink_check();
705 * Check if the link-layer address has changed or not.
711 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen))
720 * This is VERY complex. Look at it with care.
722 * override solicit lladdr llchange action
727 * 0 0 y y (1) REACHABLE->STALE
728 * 0 1 n -- (2c) *->REACHABLE
729 * 0 1 y n (2b) L *->REACHABLE
730 * 0 1 y y (1) REACHABLE->STALE
733 * 1 0 y y (2a) L *->STALE
734 * 1 1 n -- (2a) *->REACHABLE
735 * 1 1 y n (2a) L *->REACHABLE
736 * 1 1 y y (2a) L *->REACHABLE
738 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */
740 * If state is REACHABLE, make it STALE.
741 * no other updates should be done.
743 if (ln->ln_state == ND6_LLINFO_REACHABLE) {
744 ln->ln_state = ND6_LLINFO_STALE;
745 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz);
748 } else if (is_override /* (2a) */
749 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */
750 || lladdr == NULL) { /* (2c) */
752 * Update link-local address, if any.
754 if (lladdr != NULL) {
755 sdl->sdl_alen = ifp->if_addrlen;
756 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
760 * If solicited, make the state REACHABLE.
761 * If not solicited and the link-layer address was
762 * changed, make it STALE.
765 ln->ln_state = ND6_LLINFO_REACHABLE;
767 if (!ND6_LLINFO_PERMANENT(ln)) {
768 nd6_llinfo_settimer(ln,
769 (long)ND_IFINFO(ifp)->reachable * hz);
772 if (lladdr != NULL && llchange) {
773 ln->ln_state = ND6_LLINFO_STALE;
774 nd6_llinfo_settimer(ln,
775 (long)nd6_gctimer * hz);
780 if (ln->ln_router && !is_router) {
782 * The peer dropped the router flag.
783 * Remove the sender from the Default Router List and
784 * update the Destination Cache entries.
786 struct nd_defrouter *dr;
787 struct in6_addr *in6;
790 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr;
793 * Lock to protect the default router list.
794 * XXX: this might be unnecessary, since this function
795 * is only called under the network software interrupt
796 * context. However, we keep it just for safety.
799 dr = defrouter_lookup(in6, ifp);
802 else if (!ip6_forwarding) {
804 * Even if the neighbor is not in the default
805 * router list, the neighbor may be used
806 * as a next hop for some destinations
807 * (e.g. redirect case). So we must
808 * call rt6_flush explicitly.
810 rt6_flush(&ip6->ip6_src, ifp);
814 ln->ln_router = is_router;
816 rt->rt_flags &= ~RTF_REJECT;
819 struct mbuf *m_hold, *m_hold_next;
822 * reset the ln_hold in advance, to explicitly
823 * prevent a ln_hold lookup in nd6_output()
824 * (wouldn't happen, though...)
826 for (m_hold = ln->ln_hold, ln->ln_hold = NULL;
827 m_hold; m_hold = m_hold_next) {
828 m_hold_next = m_hold->m_nextpkt;
829 m_hold->m_nextpkt = NULL;
831 * we assume ifp is not a loopback here, so just set
832 * the 2nd argument as the 1st one.
834 nd6_output(ifp, ifp, m_hold,
835 (struct sockaddr_in6 *)rt_key(rt), rt);
844 icmp6stat.icp6s_badna++;
849 * Neighbor advertisement output handling.
853 * the following items are not implemented yet:
854 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
855 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
858 nd6_na_output(ifp, daddr6_0, taddr6, flags, tlladdr, sdl0)
860 const struct in6_addr *daddr6_0, *taddr6;
862 int tlladdr; /* 1 if include target link-layer address */
863 struct sockaddr *sdl0; /* sockaddr_dl (= proxy NA) or NULL */
867 struct nd_neighbor_advert *nd_na;
868 struct ip6_moptions im6o;
869 struct in6_addr *src, daddr6;
870 struct sockaddr_in6 dst_sa;
871 int icmp6len, maxlen, error;
875 bzero(&ro, sizeof(ro));
877 daddr6 = *daddr6_0; /* make a local copy for modification */
879 /* estimate the size of message */
880 maxlen = sizeof(*ip6) + sizeof(*nd_na);
881 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
882 if (max_linkhdr + maxlen >= MCLBYTES) {
884 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES "
885 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
890 MGETHDR(m, M_DONTWAIT, MT_DATA);
891 if (m && max_linkhdr + maxlen >= MHLEN) {
892 MCLGET(m, M_DONTWAIT);
893 if ((m->m_flags & M_EXT) == 0) {
900 m->m_pkthdr.rcvif = NULL;
902 if (IN6_IS_ADDR_MULTICAST(&daddr6)) {
903 m->m_flags |= M_MCAST;
904 im6o.im6o_multicast_ifp = ifp;
905 im6o.im6o_multicast_hlim = 255;
906 im6o.im6o_multicast_loop = 0;
909 icmp6len = sizeof(*nd_na);
910 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len;
911 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
913 /* fill neighbor advertisement packet */
914 ip6 = mtod(m, struct ip6_hdr *);
916 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
917 ip6->ip6_vfc |= IPV6_VERSION;
918 ip6->ip6_nxt = IPPROTO_ICMPV6;
920 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) {
922 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
923 daddr6.s6_addr16[1] = 0;
924 daddr6.s6_addr32[1] = 0;
925 daddr6.s6_addr32[2] = 0;
926 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE;
927 if (in6_setscope(&daddr6, ifp, NULL))
930 flags &= ~ND_NA_FLAG_SOLICITED;
932 ip6->ip6_dst = daddr6;
933 bzero(&dst_sa, sizeof(struct sockaddr_in6));
934 dst_sa.sin6_family = AF_INET6;
935 dst_sa.sin6_len = sizeof(struct sockaddr_in6);
936 dst_sa.sin6_addr = daddr6;
939 * Select a source whose scope is the same as that of the dest.
941 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa));
942 src = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &error);
944 char ip6buf[INET6_ADDRSTRLEN];
945 nd6log((LOG_DEBUG, "nd6_na_output: source can't be "
946 "determined: dst=%s, error=%d\n",
947 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error));
951 nd_na = (struct nd_neighbor_advert *)(ip6 + 1);
952 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT;
953 nd_na->nd_na_code = 0;
954 nd_na->nd_na_target = *taddr6;
955 in6_clearscope(&nd_na->nd_na_target); /* XXX */
958 * "tlladdr" indicates NS's condition for adding tlladdr or not.
959 * see nd6_ns_input() for details.
960 * Basically, if NS packet is sent to unicast/anycast addr,
961 * target lladdr option SHOULD NOT be included.
965 * sdl0 != NULL indicates proxy NA. If we do proxy, use
966 * lladdr in sdl0. If we are not proxying (sending NA for
967 * my address) use lladdr configured for the interface.
972 mac = carp_macmatch6(ifp->if_carp, m, taddr6);
974 mac = nd6_ifptomac(ifp);
976 mac = nd6_ifptomac(ifp);
978 } else if (sdl0->sa_family == AF_LINK) {
979 struct sockaddr_dl *sdl;
980 sdl = (struct sockaddr_dl *)sdl0;
981 if (sdl->sdl_alen == ifp->if_addrlen)
985 if (tlladdr && mac) {
986 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
987 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1);
989 /* roundup to 8 bytes alignment! */
990 optlen = (optlen + 7) & ~7;
992 m->m_pkthdr.len += optlen;
995 bzero((caddr_t)nd_opt, optlen);
996 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
997 nd_opt->nd_opt_len = optlen >> 3;
998 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
1000 flags &= ~ND_NA_FLAG_OVERRIDE;
1002 ip6->ip6_plen = htons((u_short)icmp6len);
1003 nd_na->nd_na_flags_reserved = flags;
1004 nd_na->nd_na_cksum = 0;
1005 nd_na->nd_na_cksum =
1006 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len);
1008 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL);
1009 icmp6_ifstat_inc(ifp, ifs6_out_msg);
1010 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert);
1011 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++;
1013 if (ro.ro_rt) { /* we don't cache this route. */
1030 switch (ifp->if_type) {
1038 #ifdef IFT_IEEE80211
1046 return IF_LLADDR(ifp);
1052 TAILQ_HEAD(dadq_head, dadq);
1054 TAILQ_ENTRY(dadq) dad_list;
1055 struct ifaddr *dad_ifa;
1056 int dad_count; /* max NS to send */
1057 int dad_ns_tcount; /* # of trials to send NS */
1058 int dad_ns_ocount; /* NS sent so far */
1061 struct callout dad_timer_ch;
1064 static struct dadq_head dadq;
1065 static int dad_init = 0;
1067 static struct dadq *
1073 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) {
1074 if (dp->dad_ifa == ifa)
1081 nd6_dad_starttimer(dp, ticks)
1086 callout_reset(&dp->dad_timer_ch, ticks,
1087 (void (*) __P((void *)))nd6_dad_timer, (void *)dp->dad_ifa);
1091 nd6_dad_stoptimer(dp)
1095 callout_stop(&dp->dad_timer_ch);
1099 * Start Duplicate Address Detection (DAD) for specified interface address.
1102 nd6_dad_start(ifa, delay)
1106 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1108 char ip6buf[INET6_ADDRSTRLEN];
1116 * If we don't need DAD, don't do it.
1117 * There are several cases:
1118 * - DAD is disabled (ip6_dad_count == 0)
1119 * - the interface address is anycast
1121 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
1123 "nd6_dad_start: called with non-tentative address "
1125 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1126 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1129 if (ia->ia6_flags & IN6_IFF_ANYCAST) {
1130 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1133 if (!ip6_dad_count) {
1134 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1137 if (ifa->ifa_ifp == NULL)
1138 panic("nd6_dad_start: ifa->ifa_ifp == NULL");
1139 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) {
1142 if (nd6_dad_find(ifa) != NULL) {
1143 /* DAD already in progress */
1147 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT);
1149 log(LOG_ERR, "nd6_dad_start: memory allocation failed for "
1151 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1152 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1155 bzero(dp, sizeof(*dp));
1156 callout_init(&dp->dad_timer_ch, 0);
1157 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list);
1159 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp),
1160 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1163 * Send NS packet for DAD, ip6_dad_count times.
1164 * Note that we must delay the first transmission, if this is the
1165 * first packet to be sent from the interface after interface
1166 * (re)initialization.
1169 IFAREF(ifa); /* just for safety */
1170 dp->dad_count = ip6_dad_count;
1171 dp->dad_ns_icount = dp->dad_na_icount = 0;
1172 dp->dad_ns_ocount = dp->dad_ns_tcount = 0;
1174 nd6_dad_ns_output(dp, ifa);
1175 nd6_dad_starttimer(dp,
1176 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1178 nd6_dad_starttimer(dp, delay);
1183 * terminate DAD unconditionally. used for address removals.
1193 dp = nd6_dad_find(ifa);
1195 /* DAD wasn't started yet */
1199 nd6_dad_stoptimer(dp);
1201 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1212 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1214 char ip6buf[INET6_ADDRSTRLEN];
1216 s = splnet(); /* XXX */
1220 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n");
1223 dp = nd6_dad_find(ifa);
1225 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n");
1228 if (ia->ia6_flags & IN6_IFF_DUPLICATED) {
1229 log(LOG_ERR, "nd6_dad_timer: called with duplicated address "
1231 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1232 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1235 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) {
1236 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address "
1238 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1239 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1243 /* timeouted with IFF_{RUNNING,UP} check */
1244 if (dp->dad_ns_tcount > dad_maxtry) {
1245 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n",
1246 if_name(ifa->ifa_ifp)));
1248 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1255 /* Need more checks? */
1256 if (dp->dad_ns_ocount < dp->dad_count) {
1258 * We have more NS to go. Send NS packet for DAD.
1260 nd6_dad_ns_output(dp, ifa);
1261 nd6_dad_starttimer(dp,
1262 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1265 * We have transmitted sufficient number of DAD packets.
1266 * See what we've got.
1272 if (dp->dad_na_icount) {
1274 * the check is in nd6_dad_na_input(),
1280 if (dp->dad_ns_icount) {
1281 /* We've seen NS, means DAD has failed. */
1286 /* (*dp) will be freed in nd6_dad_duplicated() */
1288 nd6_dad_duplicated(ifa);
1291 * We are done with DAD. No NA came, no NS came.
1292 * No duplicate address found.
1294 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1297 "%s: DAD complete for %s - no duplicates found\n",
1298 if_name(ifa->ifa_ifp),
1299 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1301 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1313 nd6_dad_duplicated(ifa)
1316 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1319 char ip6buf[INET6_ADDRSTRLEN];
1321 dp = nd6_dad_find(ifa);
1323 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n");
1327 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: "
1328 "NS in/out=%d/%d, NA in=%d\n",
1329 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1330 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount);
1332 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1333 ia->ia6_flags |= IN6_IFF_DUPLICATED;
1335 /* We are done with DAD, with duplicate address found. (failure) */
1336 nd6_dad_stoptimer(dp);
1339 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n",
1340 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr));
1341 log(LOG_ERR, "%s: manual intervention required\n",
1345 * If the address is a link-local address formed from an interface
1346 * identifier based on the hardware address which is supposed to be
1347 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP
1348 * operation on the interface SHOULD be disabled.
1349 * [rfc2462bis-03 Section 5.4.5]
1351 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) {
1352 struct in6_addr in6;
1355 * To avoid over-reaction, we only apply this logic when we are
1356 * very sure that hardware addresses are supposed to be unique.
1358 switch (ifp->if_type) {
1363 #ifdef IFT_IEEE80211
1366 in6 = ia->ia_addr.sin6_addr;
1367 if (in6_get_hw_ifid(ifp, &in6) == 0 &&
1368 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) {
1369 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED;
1370 log(LOG_ERR, "%s: possible hardware address "
1371 "duplication detected, disable IPv6\n",
1378 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1385 nd6_dad_ns_output(dp, ifa)
1389 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1390 struct ifnet *ifp = ifa->ifa_ifp;
1392 dp->dad_ns_tcount++;
1393 if ((ifp->if_flags & IFF_UP) == 0) {
1396 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
1400 dp->dad_ns_ocount++;
1401 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1);
1405 nd6_dad_ns_input(ifa)
1408 struct in6_ifaddr *ia;
1410 const struct in6_addr *taddr6;
1415 panic("ifa == NULL in nd6_dad_ns_input");
1417 ia = (struct in6_ifaddr *)ifa;
1419 taddr6 = &ia->ia_addr.sin6_addr;
1421 dp = nd6_dad_find(ifa);
1423 /* Quickhack - completely ignore DAD NS packets */
1424 if (dad_ignore_ns) {
1425 char ip6buf[INET6_ADDRSTRLEN];
1427 "nd6_dad_ns_input: ignoring DAD NS packet for "
1428 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6),
1429 if_name(ifa->ifa_ifp)));
1434 * if I'm yet to start DAD, someone else started using this address
1435 * first. I have a duplicate and you win.
1437 if (dp == NULL || dp->dad_ns_ocount == 0)
1440 /* XXX more checks for loopback situation - see nd6_dad_timer too */
1443 dp = NULL; /* will be freed in nd6_dad_duplicated() */
1444 nd6_dad_duplicated(ifa);
1447 * not sure if I got a duplicate.
1448 * increment ns count and see what happens.
1451 dp->dad_ns_icount++;
1456 nd6_dad_na_input(ifa)
1462 panic("ifa == NULL in nd6_dad_na_input");
1464 dp = nd6_dad_find(ifa);
1466 dp->dad_na_icount++;
1468 /* remove the address. */
1469 nd6_dad_duplicated(ifa);