1 /* $FreeBSD: src/sys/netinet6/nd6_nbr.c,v 1.4.2.6 2003/01/23 21:06:47 sam Exp $ */
2 /* $DragonFly: src/sys/netinet6/nd6_nbr.c,v 1.3 2003/08/23 11:02:45 rob Exp $ */
3 /* $KAME: nd6_nbr.c,v 1.86 2002/01/21 02:33:04 jinmei Exp $ */
6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the project nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 #include "opt_inet6.h"
36 #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/route.h>
56 #include <netinet/in.h>
57 #include <netinet/in_var.h>
58 #include <netinet6/in6_var.h>
59 #include <netinet/ip6.h>
60 #include <netinet6/ip6_var.h>
61 #include <netinet6/nd6.h>
62 #include <netinet/icmp6.h>
65 #include <netinet6/ipsec.h>
67 #include <netinet6/ipsec6.h>
71 #include <net/net_osdep.h>
73 #define SDL(s) ((struct sockaddr_dl *)s)
76 static struct dadq *nd6_dad_find (struct ifaddr *);
77 static void nd6_dad_starttimer (struct dadq *, int);
78 static void nd6_dad_stoptimer (struct dadq *);
79 static void nd6_dad_timer (struct ifaddr *);
80 static void nd6_dad_ns_output (struct dadq *, struct ifaddr *);
81 static void nd6_dad_ns_input (struct ifaddr *);
82 static void nd6_dad_na_input (struct ifaddr *);
84 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/
85 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */
88 * Input an Neighbor Solicitation Message.
91 * Based on RFC 2462 (duplicated address detection)
94 nd6_ns_input(m, off, icmp6len)
98 struct ifnet *ifp = m->m_pkthdr.rcvif;
99 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
100 struct nd_neighbor_solicit *nd_ns;
101 struct in6_addr saddr6 = ip6->ip6_src;
102 struct in6_addr daddr6 = ip6->ip6_dst;
103 struct in6_addr taddr6;
104 struct in6_addr myaddr6;
108 int anycast = 0, proxy = 0, tentative = 0;
110 union nd_opts ndopts;
111 struct sockaddr_dl *proxydl = NULL;
113 #ifndef PULLDOWN_TEST
114 IP6_EXTHDR_CHECK(m, off, icmp6len,);
115 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off);
117 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len);
119 icmp6stat.icp6s_tooshort++;
123 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */
124 taddr6 = nd_ns->nd_ns_target;
126 if (ip6->ip6_hlim != 255) {
128 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n",
129 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src),
130 ip6_sprintf(&ip6->ip6_dst), if_name(ifp)));
134 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
135 /* dst has to be solicited node multicast address. */
136 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL
137 /* don't check ifindex portion */
138 && daddr6.s6_addr32[1] == 0
139 && daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE
140 && daddr6.s6_addr8[12] == 0xff) {
143 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
144 "(wrong ip6 dst)\n"));
149 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
150 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n"));
154 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6))
155 taddr6.s6_addr16[1] = htons(ifp->if_index);
157 icmp6len -= sizeof(*nd_ns);
158 nd6_option_init(nd_ns + 1, icmp6len, &ndopts);
159 if (nd6_options(&ndopts) < 0) {
161 "nd6_ns_input: invalid ND option, ignored\n"));
162 /* nd6_options have incremented stats */
166 if (ndopts.nd_opts_src_lladdr) {
167 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
168 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
171 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) {
172 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
173 "(link-layer address option)\n"));
178 * Attaching target link-layer address to the NA?
181 * NS IP dst is unicast/anycast MUST NOT add
182 * NS IP dst is solicited-node multicast MUST add
184 * In implementation, we add target link-layer address by default.
185 * We do not add one in MUST NOT cases.
187 #if 0 /* too much! */
188 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6);
189 if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST))
193 if (!IN6_IS_ADDR_MULTICAST(&daddr6))
199 * Target address (taddr6) must be either:
200 * (1) Valid unicast/anycast address for my receiving interface,
201 * (2) Unicast address for which I'm offering proxy service, or
202 * (3) "tentative" address on which DAD is being performed.
204 /* (1) and (3) check. */
205 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
210 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 if (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 &&
219 rt->rt_gateway->sa_family == AF_LINK) {
221 * proxy NDP for single entry
223 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp,
224 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
227 proxydl = SDL(rt->rt_gateway);
235 * We've got an NS packet, and we don't have that adddress
236 * assigned for us. We MUST silently ignore it.
241 myaddr6 = *IFA_IN6(ifa);
242 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST;
243 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE;
244 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED)
247 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
249 "nd6_ns_input: lladdrlen mismatch for %s "
250 "(if %d, NS packet %d)\n",
251 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2));
255 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) {
257 "nd6_ns_input: duplicate IP6 address %s\n",
258 ip6_sprintf(&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 * duplicated 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 saddr6 = in6addr_linklocal_allnodes;
298 saddr6.s6_addr16[1] = htons(ifp->if_index);
299 nd6_na_output(ifp, &saddr6, &taddr6,
300 ((anycast || proxy || !tlladdr)
301 ? 0 : ND_NA_FLAG_OVERRIDE)
302 | (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0),
303 tlladdr, (struct sockaddr *)proxydl);
307 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_NEIGHBOR_SOLICIT, 0);
309 nd6_na_output(ifp, &saddr6, &taddr6,
310 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE)
311 | (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0)
312 | ND_NA_FLAG_SOLICITED,
313 tlladdr, (struct sockaddr *)proxydl);
319 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", ip6_sprintf(&saddr6)));
320 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", ip6_sprintf(&daddr6)));
321 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", ip6_sprintf(&taddr6)));
322 icmp6stat.icp6s_badns++;
327 * Output an Neighbor Solicitation Message. Caller specifies:
328 * - ICMP6 header source IP6 address
329 * - ND6 header target IP6 address
330 * - ND6 header source datalink address
333 * Based on RFC 2462 (duplicated address detection)
336 nd6_ns_output(ifp, daddr6, taddr6, ln, dad)
338 const struct in6_addr *daddr6, *taddr6;
339 struct llinfo_nd6 *ln; /* for source address determination */
340 int dad; /* duplicated address detection */
344 struct nd_neighbor_solicit *nd_ns;
345 struct in6_ifaddr *ia = NULL;
346 struct ip6_moptions im6o;
350 struct ifnet *outif = NULL;
352 if (IN6_IS_ADDR_MULTICAST(taddr6))
355 /* estimate the size of message */
356 maxlen = sizeof(*ip6) + sizeof(*nd_ns);
357 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
358 if (max_linkhdr + maxlen >= MCLBYTES) {
360 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES "
361 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
366 MGETHDR(m, M_DONTWAIT, MT_DATA);
367 if (m && max_linkhdr + maxlen >= MHLEN) {
368 MCLGET(m, M_DONTWAIT);
369 if ((m->m_flags & M_EXT) == 0) {
376 m->m_pkthdr.rcvif = NULL;
378 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) {
379 m->m_flags |= M_MCAST;
380 im6o.im6o_multicast_ifp = ifp;
381 im6o.im6o_multicast_hlim = 255;
382 im6o.im6o_multicast_loop = 0;
385 icmp6len = sizeof(*nd_ns);
386 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len;
387 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
389 /* fill neighbor solicitation packet */
390 ip6 = mtod(m, struct ip6_hdr *);
392 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
393 ip6->ip6_vfc |= IPV6_VERSION;
394 /* ip6->ip6_plen will be set later */
395 ip6->ip6_nxt = IPPROTO_ICMPV6;
398 ip6->ip6_dst = *daddr6;
400 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
401 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index);
402 ip6->ip6_dst.s6_addr32[1] = 0;
403 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE;
404 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3];
405 ip6->ip6_dst.s6_addr8[12] = 0xff;
408 #if 0 /* KAME way, exact address scope match */
410 * Select a source whose scope is the same as that of the dest.
411 * Typically, the dest is link-local solicitation multicast
412 * (i.e. neighbor discovery) or link-local/global unicast
413 * (i.e. neighbor un-reachability detection).
415 ia = in6_ifawithifp(ifp, &ip6->ip6_dst);
420 ip6->ip6_src = ia->ia_addr.sin6_addr;
421 #else /* spec-wise correct */
424 * "If the source address of the packet prompting the
425 * solicitation is the same as one of the addresses assigned
426 * to the outgoing interface, that address SHOULD be placed
427 * in the IP Source Address of the outgoing solicitation.
428 * Otherwise, any one of the addresses assigned to the
429 * interface should be used."
431 * We use the source address for the prompting packet
433 * - saddr6 is given from the caller (by giving "ln"), and
434 * - saddr6 belongs to the outgoing interface.
435 * Otherwise, we perform a scope-wise match.
437 struct ip6_hdr *hip6; /* hold ip6 */
438 struct in6_addr *saddr6;
440 if (ln && ln->ln_hold) {
441 hip6 = mtod(ln->ln_hold, struct ip6_hdr *);
443 if (sizeof(*hip6) < ln->ln_hold->m_len)
444 saddr6 = &hip6->ip6_src;
449 if (saddr6 && in6ifa_ifpwithaddr(ifp, saddr6))
450 bcopy(saddr6, &ip6->ip6_src, sizeof(*saddr6));
452 ia = in6_ifawithifp(ifp, &ip6->ip6_dst);
457 ip6->ip6_src = ia->ia_addr.sin6_addr;
462 * Source address for DAD packet must always be IPv6
463 * unspecified address. (0::0)
465 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src));
467 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1);
468 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT;
469 nd_ns->nd_ns_code = 0;
470 nd_ns->nd_ns_reserved = 0;
471 nd_ns->nd_ns_target = *taddr6;
473 if (IN6_IS_SCOPE_LINKLOCAL(&nd_ns->nd_ns_target))
474 nd_ns->nd_ns_target.s6_addr16[1] = 0;
477 * Add source link-layer address option.
479 * spec implementation
481 * DAD packet MUST NOT do not add the option
482 * there's no link layer address:
483 * impossible do not add the option
484 * there's link layer address:
485 * Multicast NS MUST add one add the option
486 * Unicast NS SHOULD add one add the option
488 if (!dad && (mac = nd6_ifptomac(ifp))) {
489 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
490 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
491 /* 8 byte alignments... */
492 optlen = (optlen + 7) & ~7;
494 m->m_pkthdr.len += optlen;
497 bzero((caddr_t)nd_opt, optlen);
498 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR;
499 nd_opt->nd_opt_len = optlen >> 3;
500 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
503 ip6->ip6_plen = htons((u_short)icmp6len);
504 nd_ns->nd_ns_cksum = 0;
506 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len);
508 ip6_output(m, NULL, NULL, dad ? IPV6_DADOUTPUT : 0, &im6o, &outif, NULL);
510 icmp6_ifstat_inc(outif, ifs6_out_msg);
511 icmp6_ifstat_inc(outif, ifs6_out_neighborsolicit);
513 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++;
517 * Neighbor advertisement input handling.
520 * Based on RFC 2462 (duplicated address detection)
522 * the following items are not implemented yet:
523 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
524 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
527 nd6_na_input(m, off, icmp6len)
531 struct ifnet *ifp = m->m_pkthdr.rcvif;
532 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
533 struct nd_neighbor_advert *nd_na;
535 struct in6_addr saddr6 = ip6->ip6_src;
537 struct in6_addr daddr6 = ip6->ip6_dst;
538 struct in6_addr taddr6;
546 struct llinfo_nd6 *ln;
548 struct sockaddr_dl *sdl;
549 union nd_opts ndopts;
551 if (ip6->ip6_hlim != 255) {
553 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n",
554 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src),
555 ip6_sprintf(&ip6->ip6_dst), if_name(ifp)));
559 #ifndef PULLDOWN_TEST
560 IP6_EXTHDR_CHECK(m, off, icmp6len,);
561 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off);
563 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len);
565 icmp6stat.icp6s_tooshort++;
569 taddr6 = nd_na->nd_na_target;
570 flags = nd_na->nd_na_flags_reserved;
571 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0);
572 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0);
573 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0);
575 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6))
576 taddr6.s6_addr16[1] = htons(ifp->if_index);
578 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
580 "nd6_na_input: invalid target address %s\n",
581 ip6_sprintf(&taddr6)));
584 if (IN6_IS_ADDR_MULTICAST(&daddr6))
587 "nd6_na_input: a solicited adv is multicasted\n"));
591 icmp6len -= sizeof(*nd_na);
592 nd6_option_init(nd_na + 1, icmp6len, &ndopts);
593 if (nd6_options(&ndopts) < 0) {
595 "nd6_na_input: invalid ND option, ignored\n"));
596 /* nd6_options have incremented stats */
600 if (ndopts.nd_opts_tgt_lladdr) {
601 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
602 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
605 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
608 * Target address matches one of my interface address.
610 * If my address is tentative, this means that there's somebody
611 * already using the same address as mine. This indicates DAD failure.
612 * This is defined in RFC 2462.
614 * Otherwise, process as defined in RFC 2461.
617 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) {
618 nd6_dad_na_input(ifa);
622 /* Just for safety, maybe unnecessary. */
625 "nd6_na_input: duplicate IP6 address %s\n",
626 ip6_sprintf(&taddr6));
630 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
632 "nd6_na_input: lladdrlen mismatch for %s "
633 "(if %d, NA packet %d)\n",
634 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2));
639 * If no neighbor cache entry is found, NA SHOULD silently be discarded.
641 rt = nd6_lookup(&taddr6, 0, ifp);
643 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) ||
644 ((sdl = SDL(rt->rt_gateway)) == NULL))
647 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
649 * If the link-layer has address, and no lladdr option came,
650 * discard the packet.
652 if (ifp->if_addrlen && !lladdr)
656 * Record link-layer address, and update the state.
658 sdl->sdl_alen = ifp->if_addrlen;
659 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
661 ln->ln_state = ND6_LLINFO_REACHABLE;
664 ln->ln_expire = time_second +
665 nd_ifinfo[rt->rt_ifp->if_index].reachable;
667 ln->ln_state = ND6_LLINFO_STALE;
668 ln->ln_expire = time_second + nd6_gctimer;
670 if ((ln->ln_router = is_router) != 0) {
672 * This means a router's state has changed from
673 * non-reachable to probably reachable, and might
674 * affect the status of associated prefixes..
676 pfxlist_onlink_check();
682 * Check if the link-layer address has changed or not.
688 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen))
697 * This is VERY complex. Look at it with care.
699 * override solicit lladdr llchange action
704 * 0 0 y y (1) REACHABLE->STALE
705 * 0 1 n -- (2c) *->REACHABLE
706 * 0 1 y n (2b) L *->REACHABLE
707 * 0 1 y y (1) REACHABLE->STALE
710 * 1 0 y y (2a) L *->STALE
711 * 1 1 n -- (2a) *->REACHABLE
712 * 1 1 y n (2a) L *->REACHABLE
713 * 1 1 y y (2a) L *->REACHABLE
715 if (!is_override && (lladdr && llchange)) { /* (1) */
717 * If state is REACHABLE, make it STALE.
718 * no other updates should be done.
720 if (ln->ln_state == ND6_LLINFO_REACHABLE) {
721 ln->ln_state = ND6_LLINFO_STALE;
722 ln->ln_expire = time_second + nd6_gctimer;
725 } else if (is_override /* (2a) */
726 || (!is_override && (lladdr && !llchange)) /* (2b) */
727 || !lladdr) { /* (2c) */
729 * Update link-local address, if any.
732 sdl->sdl_alen = ifp->if_addrlen;
733 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
737 * If solicited, make the state REACHABLE.
738 * If not solicited and the link-layer address was
739 * changed, make it STALE.
742 ln->ln_state = ND6_LLINFO_REACHABLE;
745 ln->ln_expire = time_second +
746 nd_ifinfo[ifp->if_index].reachable;
749 if (lladdr && llchange) {
750 ln->ln_state = ND6_LLINFO_STALE;
751 ln->ln_expire = time_second + nd6_gctimer;
756 if (ln->ln_router && !is_router) {
758 * The peer dropped the router flag.
759 * Remove the sender from the Default Router List and
760 * update the Destination Cache entries.
762 struct nd_defrouter *dr;
763 struct in6_addr *in6;
766 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr;
769 * Lock to protect the default router list.
770 * XXX: this might be unnecessary, since this function
771 * is only called under the network software interrupt
772 * context. However, we keep it just for safety.
775 dr = defrouter_lookup(in6, rt->rt_ifp);
778 else if (!ip6_forwarding && ip6_accept_rtadv) {
780 * Even if the neighbor is not in the default
781 * router list, the neighbor may be used
782 * as a next hop for some destinations
783 * (e.g. redirect case). So we must
784 * call rt6_flush explicitly.
786 rt6_flush(&ip6->ip6_src, rt->rt_ifp);
790 ln->ln_router = is_router;
792 rt->rt_flags &= ~RTF_REJECT;
796 * we assume ifp is not a loopback here, so just set the 2nd
797 * argument as the 1st one.
799 nd6_output(ifp, ifp, ln->ln_hold,
800 (struct sockaddr_in6 *)rt_key(rt), rt);
809 icmp6stat.icp6s_badna++;
814 * Neighbor advertisement output handling.
818 * the following items are not implemented yet:
819 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
820 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
823 nd6_na_output(ifp, daddr6, taddr6, flags, tlladdr, sdl0)
825 const struct in6_addr *daddr6, *taddr6;
827 int tlladdr; /* 1 if include target link-layer address */
828 struct sockaddr *sdl0; /* sockaddr_dl (= proxy NA) or NULL */
832 struct nd_neighbor_advert *nd_na;
833 struct in6_ifaddr *ia = NULL;
834 struct ip6_moptions im6o;
838 struct ifnet *outif = NULL;
840 /* estimate the size of message */
841 maxlen = sizeof(*ip6) + sizeof(*nd_na);
842 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
843 if (max_linkhdr + maxlen >= MCLBYTES) {
845 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES "
846 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
851 MGETHDR(m, M_DONTWAIT, MT_DATA);
852 if (m && max_linkhdr + maxlen >= MHLEN) {
853 MCLGET(m, M_DONTWAIT);
854 if ((m->m_flags & M_EXT) == 0) {
861 m->m_pkthdr.rcvif = NULL;
863 if (IN6_IS_ADDR_MULTICAST(daddr6)) {
864 m->m_flags |= M_MCAST;
865 im6o.im6o_multicast_ifp = ifp;
866 im6o.im6o_multicast_hlim = 255;
867 im6o.im6o_multicast_loop = 0;
870 icmp6len = sizeof(*nd_na);
871 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len;
872 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
874 /* fill neighbor advertisement packet */
875 ip6 = mtod(m, struct ip6_hdr *);
877 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
878 ip6->ip6_vfc |= IPV6_VERSION;
879 ip6->ip6_nxt = IPPROTO_ICMPV6;
881 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) {
883 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
884 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index);
885 ip6->ip6_dst.s6_addr32[1] = 0;
886 ip6->ip6_dst.s6_addr32[2] = 0;
887 ip6->ip6_dst.s6_addr32[3] = IPV6_ADDR_INT32_ONE;
888 flags &= ~ND_NA_FLAG_SOLICITED;
890 ip6->ip6_dst = *daddr6;
893 * Select a source whose scope is the same as that of the dest.
895 ia = in6_ifawithifp(ifp, &ip6->ip6_dst);
900 ip6->ip6_src = ia->ia_addr.sin6_addr;
901 nd_na = (struct nd_neighbor_advert *)(ip6 + 1);
902 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT;
903 nd_na->nd_na_code = 0;
904 nd_na->nd_na_target = *taddr6;
905 if (IN6_IS_SCOPE_LINKLOCAL(&nd_na->nd_na_target))
906 nd_na->nd_na_target.s6_addr16[1] = 0;
909 * "tlladdr" indicates NS's condition for adding tlladdr or not.
910 * see nd6_ns_input() for details.
911 * Basically, if NS packet is sent to unicast/anycast addr,
912 * target lladdr option SHOULD NOT be included.
917 * sdl0 != NULL indicates proxy NA. If we do proxy, use
918 * lladdr in sdl0. If we are not proxying (sending NA for
919 * my address) use lladdr configured for the interface.
922 mac = nd6_ifptomac(ifp);
923 else if (sdl0->sa_family == AF_LINK) {
924 struct sockaddr_dl *sdl;
925 sdl = (struct sockaddr_dl *)sdl0;
926 if (sdl->sdl_alen == ifp->if_addrlen)
930 if (tlladdr && mac) {
931 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
932 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1);
934 /* roundup to 8 bytes alignment! */
935 optlen = (optlen + 7) & ~7;
937 m->m_pkthdr.len += optlen;
940 bzero((caddr_t)nd_opt, optlen);
941 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
942 nd_opt->nd_opt_len = optlen >> 3;
943 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
945 flags &= ~ND_NA_FLAG_OVERRIDE;
947 ip6->ip6_plen = htons((u_short)icmp6len);
948 nd_na->nd_na_flags_reserved = flags;
949 nd_na->nd_na_cksum = 0;
951 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len);
953 ip6_output(m, NULL, NULL, 0, &im6o, &outif, NULL);
955 icmp6_ifstat_inc(outif, ifs6_out_msg);
956 icmp6_ifstat_inc(outif, ifs6_out_neighboradvert);
958 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++;
965 switch (ifp->if_type) {
976 return ((caddr_t)(ifp + 1));
983 TAILQ_HEAD(dadq_head, dadq);
985 TAILQ_ENTRY(dadq) dad_list;
986 struct ifaddr *dad_ifa;
987 int dad_count; /* max NS to send */
988 int dad_ns_tcount; /* # of trials to send NS */
989 int dad_ns_ocount; /* NS sent so far */
992 struct callout dad_timer_ch;
995 static struct dadq_head dadq;
996 static int dad_init = 0;
1004 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) {
1005 if (dp->dad_ifa == ifa)
1012 nd6_dad_starttimer(dp, ticks)
1017 callout_reset(&dp->dad_timer_ch, ticks,
1018 (void (*) (void *))nd6_dad_timer, (void *)dp->dad_ifa);
1022 nd6_dad_stoptimer(dp)
1026 callout_stop(&dp->dad_timer_ch);
1030 * Start Duplicated Address Detection (DAD) for specified interface address.
1033 nd6_dad_start(ifa, tick)
1035 int *tick; /* minimum delay ticks for IFF_UP event */
1037 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1046 * If we don't need DAD, don't do it.
1047 * There are several cases:
1048 * - DAD is disabled (ip6_dad_count == 0)
1049 * - the interface address is anycast
1051 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
1053 "nd6_dad_start: called with non-tentative address "
1055 ip6_sprintf(&ia->ia_addr.sin6_addr),
1056 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1059 if (ia->ia6_flags & IN6_IFF_ANYCAST) {
1060 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1063 if (!ip6_dad_count) {
1064 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1068 panic("nd6_dad_start: ifa->ifa_ifp == NULL");
1069 if (!(ifa->ifa_ifp->if_flags & IFF_UP))
1071 if (nd6_dad_find(ifa) != NULL) {
1072 /* DAD already in progress */
1076 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT);
1078 log(LOG_ERR, "nd6_dad_start: memory allocation failed for "
1080 ip6_sprintf(&ia->ia_addr.sin6_addr),
1081 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1084 bzero(dp, sizeof(*dp));
1085 callout_init(&dp->dad_timer_ch);
1086 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list);
1088 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp),
1089 ip6_sprintf(&ia->ia_addr.sin6_addr)));
1092 * Send NS packet for DAD, ip6_dad_count times.
1093 * Note that we must delay the first transmission, if this is the
1094 * first packet to be sent from the interface after interface
1095 * (re)initialization.
1098 IFAREF(ifa); /* just for safety */
1099 dp->dad_count = ip6_dad_count;
1100 dp->dad_ns_icount = dp->dad_na_icount = 0;
1101 dp->dad_ns_ocount = dp->dad_ns_tcount = 0;
1103 nd6_dad_ns_output(dp, ifa);
1104 nd6_dad_starttimer(dp,
1105 nd_ifinfo[ifa->ifa_ifp->if_index].retrans * hz / 1000);
1110 ntick = random() % (MAX_RTR_SOLICITATION_DELAY * hz);
1112 ntick = *tick + random() % (hz / 2);
1114 nd6_dad_starttimer(dp, ntick);
1119 * terminate DAD unconditionally. used for address removals.
1129 dp = nd6_dad_find(ifa);
1131 /* DAD wasn't started yet */
1135 nd6_dad_stoptimer(dp);
1137 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1148 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1151 s = splnet(); /* XXX */
1155 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n");
1158 dp = nd6_dad_find(ifa);
1160 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n");
1163 if (ia->ia6_flags & IN6_IFF_DUPLICATED) {
1164 log(LOG_ERR, "nd6_dad_timer: called with duplicated address "
1166 ip6_sprintf(&ia->ia_addr.sin6_addr),
1167 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1170 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) {
1171 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address "
1173 ip6_sprintf(&ia->ia_addr.sin6_addr),
1174 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1178 /* timeouted with IFF_{RUNNING,UP} check */
1179 if (dp->dad_ns_tcount > dad_maxtry) {
1180 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n",
1181 if_name(ifa->ifa_ifp)));
1183 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1190 /* Need more checks? */
1191 if (dp->dad_ns_ocount < dp->dad_count) {
1193 * We have more NS to go. Send NS packet for DAD.
1195 nd6_dad_ns_output(dp, ifa);
1196 nd6_dad_starttimer(dp,
1197 nd_ifinfo[ifa->ifa_ifp->if_index].retrans * hz / 1000);
1200 * We have transmitted sufficient number of DAD packets.
1201 * See what we've got.
1207 if (dp->dad_na_icount) {
1209 * the check is in nd6_dad_na_input(),
1215 if (dp->dad_ns_icount) {
1216 #if 0 /* heuristics */
1219 * - we have sent many(?) DAD NS, and
1220 * - the number of NS we sent equals to the
1221 * number of NS we've got, and
1223 * we may have a faulty network card/driver which
1224 * loops back multicasts to myself.
1226 if (3 < dp->dad_count
1227 && dp->dad_ns_icount == dp->dad_count
1228 && dp->dad_na_icount == 0) {
1229 log(LOG_INFO, "DAD questionable for %s(%s): "
1230 "network card loops back multicast?\n",
1231 ip6_sprintf(&ia->ia_addr.sin6_addr),
1232 if_name(ifa->ifa_ifp));
1233 /* XXX consider it a duplicate or not? */
1236 /* We've seen NS, means DAD has failed. */
1240 /* We've seen NS, means DAD has failed. */
1246 /* (*dp) will be freed in nd6_dad_duplicated() */
1248 nd6_dad_duplicated(ifa);
1251 * We are done with DAD. No NA came, no NS came.
1252 * duplicated address found.
1254 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1257 "%s: DAD complete for %s - no duplicates found\n",
1258 if_name(ifa->ifa_ifp),
1259 ip6_sprintf(&ia->ia_addr.sin6_addr)));
1261 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1273 nd6_dad_duplicated(ifa)
1276 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1279 dp = nd6_dad_find(ifa);
1281 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n");
1285 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: "
1286 "NS in/out=%d/%d, NA in=%d\n",
1287 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr),
1288 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount);
1290 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1291 ia->ia6_flags |= IN6_IFF_DUPLICATED;
1293 /* We are done with DAD, with duplicated address found. (failure) */
1294 nd6_dad_stoptimer(dp);
1296 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n",
1297 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr));
1298 log(LOG_ERR, "%s: manual intervention required\n",
1299 if_name(ifa->ifa_ifp));
1301 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1308 nd6_dad_ns_output(dp, ifa)
1312 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1313 struct ifnet *ifp = ifa->ifa_ifp;
1315 dp->dad_ns_tcount++;
1316 if ((ifp->if_flags & IFF_UP) == 0) {
1318 printf("%s: interface down?\n", if_name(ifp));
1322 if ((ifp->if_flags & IFF_RUNNING) == 0) {
1324 printf("%s: interface not running?\n", if_name(ifp));
1329 dp->dad_ns_ocount++;
1330 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1);
1334 nd6_dad_ns_input(ifa)
1337 struct in6_ifaddr *ia;
1339 const struct in6_addr *taddr6;
1344 panic("ifa == NULL in nd6_dad_ns_input");
1346 ia = (struct in6_ifaddr *)ifa;
1348 taddr6 = &ia->ia_addr.sin6_addr;
1350 dp = nd6_dad_find(ifa);
1352 /* Quickhack - completely ignore DAD NS packets */
1353 if (dad_ignore_ns) {
1355 "nd6_dad_ns_input: ignoring DAD NS packet for "
1356 "address %s(%s)\n", ip6_sprintf(taddr6),
1357 if_name(ifa->ifa_ifp)));
1362 * if I'm yet to start DAD, someone else started using this address
1363 * first. I have a duplicate and you win.
1365 if (!dp || dp->dad_ns_ocount == 0)
1368 /* XXX more checks for loopback situation - see nd6_dad_timer too */
1371 dp = NULL; /* will be freed in nd6_dad_duplicated() */
1372 nd6_dad_duplicated(ifa);
1375 * not sure if I got a duplicate.
1376 * increment ns count and see what happens.
1379 dp->dad_ns_icount++;
1384 nd6_dad_na_input(ifa)
1390 panic("ifa == NULL in nd6_dad_na_input");
1392 dp = nd6_dad_find(ifa);
1394 dp->dad_na_icount++;
1396 /* remove the address. */
1397 nd6_dad_duplicated(ifa);