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 1.6 2004/08/02 13:22:33 joerg 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(struct mbuf *m, int off, int 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;
106 int anycast = 0, proxy = 0, tentative = 0;
108 union nd_opts ndopts;
109 struct sockaddr_dl *proxydl = NULL;
111 #ifndef PULLDOWN_TEST
112 IP6_EXTHDR_CHECK(m, off, icmp6len,);
113 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off);
115 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len);
117 icmp6stat.icp6s_tooshort++;
121 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */
122 taddr6 = nd_ns->nd_ns_target;
124 if (ip6->ip6_hlim != 255) {
126 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n",
127 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src),
128 ip6_sprintf(&ip6->ip6_dst), if_name(ifp)));
132 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
133 /* dst has to be solicited node multicast address. */
134 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL
135 /* don't check ifindex portion */
136 && daddr6.s6_addr32[1] == 0
137 && daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE
138 && daddr6.s6_addr8[12] == 0xff) {
141 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
142 "(wrong ip6 dst)\n"));
147 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
148 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n"));
152 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6))
153 taddr6.s6_addr16[1] = htons(ifp->if_index);
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 0 /* too much! */
186 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6);
187 if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST))
191 if (!IN6_IS_ADDR_MULTICAST(&daddr6))
197 * Target address (taddr6) must be either:
198 * (1) Valid unicast/anycast address for my receiving interface,
199 * (2) Unicast address for which I'm offering proxy service, or
200 * (3) "tentative" address on which DAD is being performed.
202 /* (1) and (3) check. */
203 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
208 struct sockaddr_in6 tsin6;
210 bzero(&tsin6, sizeof tsin6);
211 tsin6.sin6_len = sizeof(struct sockaddr_in6);
212 tsin6.sin6_family = AF_INET6;
213 tsin6.sin6_addr = taddr6;
215 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0);
216 if (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 &&
217 rt->rt_gateway->sa_family == AF_LINK) {
219 * proxy NDP for single entry
221 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp,
222 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
225 proxydl = SDL(rt->rt_gateway);
233 * We've got an NS packet, and we don't have that adddress
234 * assigned for us. We MUST silently ignore it.
239 myaddr6 = *IFA_IN6(ifa);
240 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST;
241 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE;
242 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED)
245 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
247 "nd6_ns_input: lladdrlen mismatch for %s "
248 "(if %d, NS packet %d)\n",
249 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2));
253 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) {
255 "nd6_ns_input: duplicate IP6 address %s\n",
256 ip6_sprintf(&saddr6)));
261 * We have neighbor solicitation packet, with target address equals to
262 * one of my tentative address.
264 * src addr how to process?
266 * multicast of course, invalid (rejected in ip6_input)
267 * unicast somebody is doing address resolution -> ignore
268 * unspec dup address detection
270 * The processing is defined in RFC 2462.
274 * If source address is unspecified address, it is for
275 * duplicated address detection.
277 * If not, the packet is for addess resolution;
278 * silently ignore it.
280 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6))
281 nd6_dad_ns_input(ifa);
287 * If the source address is unspecified address, entries must not
288 * be created or updated.
289 * It looks that sender is performing DAD. Output NA toward
290 * all-node multicast address, to tell the sender that I'm using
292 * S bit ("solicited") must be zero.
294 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
295 saddr6 = in6addr_linklocal_allnodes;
296 saddr6.s6_addr16[1] = htons(ifp->if_index);
297 nd6_na_output(ifp, &saddr6, &taddr6,
298 ((anycast || proxy || !tlladdr)
299 ? 0 : ND_NA_FLAG_OVERRIDE)
300 | (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0),
301 tlladdr, (struct sockaddr *)proxydl);
305 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_NEIGHBOR_SOLICIT, 0);
307 nd6_na_output(ifp, &saddr6, &taddr6,
308 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE)
309 | (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0)
310 | ND_NA_FLAG_SOLICITED,
311 tlladdr, (struct sockaddr *)proxydl);
317 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", ip6_sprintf(&saddr6)));
318 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", ip6_sprintf(&daddr6)));
319 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", ip6_sprintf(&taddr6)));
320 icmp6stat.icp6s_badns++;
325 * Output an Neighbor Solicitation Message. Caller specifies:
326 * - ICMP6 header source IP6 address
327 * - ND6 header target IP6 address
328 * - ND6 header source datalink address
331 * Based on RFC 2462 (duplicated address detection)
334 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6,
335 const struct in6_addr *taddr6,
336 struct llinfo_nd6 *ln, /* for source address determination */
337 int dad) /* duplicated address detection */
341 struct nd_neighbor_solicit *nd_ns;
342 struct in6_ifaddr *ia = NULL;
343 struct ip6_moptions im6o;
347 struct ifnet *outif = NULL;
349 if (IN6_IS_ADDR_MULTICAST(taddr6))
352 /* estimate the size of message */
353 maxlen = sizeof(*ip6) + sizeof(*nd_ns);
354 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
355 if (max_linkhdr + maxlen >= MCLBYTES) {
357 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES "
358 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
363 MGETHDR(m, MB_DONTWAIT, MT_DATA);
364 if (m && max_linkhdr + maxlen >= MHLEN) {
365 MCLGET(m, MB_DONTWAIT);
366 if ((m->m_flags & M_EXT) == 0) {
373 m->m_pkthdr.rcvif = NULL;
375 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) {
376 m->m_flags |= M_MCAST;
377 im6o.im6o_multicast_ifp = ifp;
378 im6o.im6o_multicast_hlim = 255;
379 im6o.im6o_multicast_loop = 0;
382 icmp6len = sizeof(*nd_ns);
383 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len;
384 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
386 /* fill neighbor solicitation packet */
387 ip6 = mtod(m, struct ip6_hdr *);
389 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
390 ip6->ip6_vfc |= IPV6_VERSION;
391 /* ip6->ip6_plen will be set later */
392 ip6->ip6_nxt = IPPROTO_ICMPV6;
395 ip6->ip6_dst = *daddr6;
397 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
398 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index);
399 ip6->ip6_dst.s6_addr32[1] = 0;
400 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE;
401 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3];
402 ip6->ip6_dst.s6_addr8[12] = 0xff;
405 #if 0 /* KAME way, exact address scope match */
407 * Select a source whose scope is the same as that of the dest.
408 * Typically, the dest is link-local solicitation multicast
409 * (i.e. neighbor discovery) or link-local/global unicast
410 * (i.e. neighbor un-reachability detection).
412 ia = in6_ifawithifp(ifp, &ip6->ip6_dst);
417 ip6->ip6_src = ia->ia_addr.sin6_addr;
418 #else /* spec-wise correct */
421 * "If the source address of the packet prompting the
422 * solicitation is the same as one of the addresses assigned
423 * to the outgoing interface, that address SHOULD be placed
424 * in the IP Source Address of the outgoing solicitation.
425 * Otherwise, any one of the addresses assigned to the
426 * interface should be used."
428 * We use the source address for the prompting packet
430 * - saddr6 is given from the caller (by giving "ln"), and
431 * - saddr6 belongs to the outgoing interface.
432 * Otherwise, we perform a scope-wise match.
434 struct ip6_hdr *hip6; /* hold ip6 */
435 struct in6_addr *saddr6;
437 if (ln && ln->ln_hold) {
438 hip6 = mtod(ln->ln_hold, struct ip6_hdr *);
440 if (sizeof(*hip6) < ln->ln_hold->m_len)
441 saddr6 = &hip6->ip6_src;
446 if (saddr6 && in6ifa_ifpwithaddr(ifp, saddr6))
447 bcopy(saddr6, &ip6->ip6_src, sizeof(*saddr6));
449 ia = in6_ifawithifp(ifp, &ip6->ip6_dst);
454 ip6->ip6_src = ia->ia_addr.sin6_addr;
459 * Source address for DAD packet must always be IPv6
460 * unspecified address. (0::0)
462 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src));
464 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1);
465 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT;
466 nd_ns->nd_ns_code = 0;
467 nd_ns->nd_ns_reserved = 0;
468 nd_ns->nd_ns_target = *taddr6;
470 if (IN6_IS_SCOPE_LINKLOCAL(&nd_ns->nd_ns_target))
471 nd_ns->nd_ns_target.s6_addr16[1] = 0;
474 * Add source link-layer address option.
476 * spec implementation
478 * DAD packet MUST NOT do not add the option
479 * there's no link layer address:
480 * impossible do not add the option
481 * there's link layer address:
482 * Multicast NS MUST add one add the option
483 * Unicast NS SHOULD add one add the option
485 if (!dad && (mac = nd6_ifptomac(ifp))) {
486 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
487 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
488 /* 8 byte alignments... */
489 optlen = (optlen + 7) & ~7;
491 m->m_pkthdr.len += optlen;
494 bzero((caddr_t)nd_opt, optlen);
495 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR;
496 nd_opt->nd_opt_len = optlen >> 3;
497 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
500 ip6->ip6_plen = htons((u_short)icmp6len);
501 nd_ns->nd_ns_cksum = 0;
503 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len);
505 ip6_output(m, NULL, NULL, dad ? IPV6_DADOUTPUT : 0, &im6o, &outif, NULL);
507 icmp6_ifstat_inc(outif, ifs6_out_msg);
508 icmp6_ifstat_inc(outif, ifs6_out_neighborsolicit);
510 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++;
514 * Neighbor advertisement input handling.
517 * Based on RFC 2462 (duplicated address detection)
519 * the following items are not implemented yet:
520 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
521 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
524 nd6_na_input(struct mbuf *m, int off, int icmp6len)
526 struct ifnet *ifp = m->m_pkthdr.rcvif;
527 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
528 struct nd_neighbor_advert *nd_na;
530 struct in6_addr saddr6 = ip6->ip6_src;
532 struct in6_addr daddr6 = ip6->ip6_dst;
533 struct in6_addr taddr6;
541 struct llinfo_nd6 *ln;
543 struct sockaddr_dl *sdl;
544 union nd_opts ndopts;
546 if (ip6->ip6_hlim != 255) {
548 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n",
549 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src),
550 ip6_sprintf(&ip6->ip6_dst), if_name(ifp)));
554 #ifndef PULLDOWN_TEST
555 IP6_EXTHDR_CHECK(m, off, icmp6len,);
556 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off);
558 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len);
560 icmp6stat.icp6s_tooshort++;
564 taddr6 = nd_na->nd_na_target;
565 flags = nd_na->nd_na_flags_reserved;
566 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0);
567 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0);
568 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0);
570 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6))
571 taddr6.s6_addr16[1] = htons(ifp->if_index);
573 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
575 "nd6_na_input: invalid target address %s\n",
576 ip6_sprintf(&taddr6)));
579 if (IN6_IS_ADDR_MULTICAST(&daddr6))
582 "nd6_na_input: a solicited adv is multicasted\n"));
586 icmp6len -= sizeof(*nd_na);
587 nd6_option_init(nd_na + 1, icmp6len, &ndopts);
588 if (nd6_options(&ndopts) < 0) {
590 "nd6_na_input: invalid ND option, ignored\n"));
591 /* nd6_options have incremented stats */
595 if (ndopts.nd_opts_tgt_lladdr) {
596 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
597 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
600 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
603 * Target address matches one of my interface address.
605 * If my address is tentative, this means that there's somebody
606 * already using the same address as mine. This indicates DAD failure.
607 * This is defined in RFC 2462.
609 * Otherwise, process as defined in RFC 2461.
612 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) {
613 nd6_dad_na_input(ifa);
617 /* Just for safety, maybe unnecessary. */
620 "nd6_na_input: duplicate IP6 address %s\n",
621 ip6_sprintf(&taddr6));
625 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
627 "nd6_na_input: lladdrlen mismatch for %s "
628 "(if %d, NA packet %d)\n",
629 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2));
634 * If no neighbor cache entry is found, NA SHOULD silently be discarded.
636 rt = nd6_lookup(&taddr6, 0, ifp);
638 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) ||
639 ((sdl = SDL(rt->rt_gateway)) == NULL))
642 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
644 * If the link-layer has address, and no lladdr option came,
645 * discard the packet.
647 if (ifp->if_addrlen && !lladdr)
651 * Record link-layer address, and update the state.
653 sdl->sdl_alen = ifp->if_addrlen;
654 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
656 ln->ln_state = ND6_LLINFO_REACHABLE;
659 ln->ln_expire = time_second +
660 nd_ifinfo[rt->rt_ifp->if_index].reachable;
662 ln->ln_state = ND6_LLINFO_STALE;
663 ln->ln_expire = time_second + nd6_gctimer;
665 if ((ln->ln_router = is_router) != 0) {
667 * This means a router's state has changed from
668 * non-reachable to probably reachable, and might
669 * affect the status of associated prefixes..
671 pfxlist_onlink_check();
677 * Check if the link-layer address has changed or not.
683 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen))
692 * This is VERY complex. Look at it with care.
694 * override solicit lladdr llchange action
699 * 0 0 y y (1) REACHABLE->STALE
700 * 0 1 n -- (2c) *->REACHABLE
701 * 0 1 y n (2b) L *->REACHABLE
702 * 0 1 y y (1) REACHABLE->STALE
705 * 1 0 y y (2a) L *->STALE
706 * 1 1 n -- (2a) *->REACHABLE
707 * 1 1 y n (2a) L *->REACHABLE
708 * 1 1 y y (2a) L *->REACHABLE
710 if (!is_override && (lladdr && llchange)) { /* (1) */
712 * If state is REACHABLE, make it STALE.
713 * no other updates should be done.
715 if (ln->ln_state == ND6_LLINFO_REACHABLE) {
716 ln->ln_state = ND6_LLINFO_STALE;
717 ln->ln_expire = time_second + nd6_gctimer;
720 } else if (is_override /* (2a) */
721 || (!is_override && (lladdr && !llchange)) /* (2b) */
722 || !lladdr) { /* (2c) */
724 * Update link-local address, if any.
727 sdl->sdl_alen = ifp->if_addrlen;
728 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
732 * If solicited, make the state REACHABLE.
733 * If not solicited and the link-layer address was
734 * changed, make it STALE.
737 ln->ln_state = ND6_LLINFO_REACHABLE;
740 ln->ln_expire = time_second +
741 nd_ifinfo[ifp->if_index].reachable;
744 if (lladdr && llchange) {
745 ln->ln_state = ND6_LLINFO_STALE;
746 ln->ln_expire = time_second + nd6_gctimer;
751 if (ln->ln_router && !is_router) {
753 * The peer dropped the router flag.
754 * Remove the sender from the Default Router List and
755 * update the Destination Cache entries.
757 struct nd_defrouter *dr;
758 struct in6_addr *in6;
761 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr;
764 * Lock to protect the default router list.
765 * XXX: this might be unnecessary, since this function
766 * is only called under the network software interrupt
767 * context. However, we keep it just for safety.
770 dr = defrouter_lookup(in6, rt->rt_ifp);
773 else if (!ip6_forwarding && ip6_accept_rtadv) {
775 * Even if the neighbor is not in the default
776 * router list, the neighbor may be used
777 * as a next hop for some destinations
778 * (e.g. redirect case). So we must
779 * call rt6_flush explicitly.
781 rt6_flush(&ip6->ip6_src, rt->rt_ifp);
785 ln->ln_router = is_router;
787 rt->rt_flags &= ~RTF_REJECT;
791 * we assume ifp is not a loopback here, so just set the 2nd
792 * argument as the 1st one.
794 nd6_output(ifp, ifp, ln->ln_hold,
795 (struct sockaddr_in6 *)rt_key(rt), rt);
804 icmp6stat.icp6s_badna++;
809 * Neighbor advertisement output handling.
813 * the following items are not implemented yet:
814 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
815 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
818 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6,
819 const struct in6_addr *taddr6, u_long flags,
820 int tlladdr, /* 1 if include target link-layer address */
821 struct sockaddr *sdl0) /* sockaddr_dl (= proxy NA) or NULL */
825 struct nd_neighbor_advert *nd_na;
826 struct in6_ifaddr *ia = NULL;
827 struct ip6_moptions im6o;
831 struct ifnet *outif = NULL;
833 /* estimate the size of message */
834 maxlen = sizeof(*ip6) + sizeof(*nd_na);
835 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
836 if (max_linkhdr + maxlen >= MCLBYTES) {
838 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES "
839 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
844 MGETHDR(m, MB_DONTWAIT, MT_DATA);
845 if (m && max_linkhdr + maxlen >= MHLEN) {
846 MCLGET(m, MB_DONTWAIT);
847 if ((m->m_flags & M_EXT) == 0) {
854 m->m_pkthdr.rcvif = NULL;
856 if (IN6_IS_ADDR_MULTICAST(daddr6)) {
857 m->m_flags |= M_MCAST;
858 im6o.im6o_multicast_ifp = ifp;
859 im6o.im6o_multicast_hlim = 255;
860 im6o.im6o_multicast_loop = 0;
863 icmp6len = sizeof(*nd_na);
864 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len;
865 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
867 /* fill neighbor advertisement packet */
868 ip6 = mtod(m, struct ip6_hdr *);
870 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
871 ip6->ip6_vfc |= IPV6_VERSION;
872 ip6->ip6_nxt = IPPROTO_ICMPV6;
874 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) {
876 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
877 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index);
878 ip6->ip6_dst.s6_addr32[1] = 0;
879 ip6->ip6_dst.s6_addr32[2] = 0;
880 ip6->ip6_dst.s6_addr32[3] = IPV6_ADDR_INT32_ONE;
881 flags &= ~ND_NA_FLAG_SOLICITED;
883 ip6->ip6_dst = *daddr6;
886 * Select a source whose scope is the same as that of the dest.
888 ia = in6_ifawithifp(ifp, &ip6->ip6_dst);
893 ip6->ip6_src = ia->ia_addr.sin6_addr;
894 nd_na = (struct nd_neighbor_advert *)(ip6 + 1);
895 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT;
896 nd_na->nd_na_code = 0;
897 nd_na->nd_na_target = *taddr6;
898 if (IN6_IS_SCOPE_LINKLOCAL(&nd_na->nd_na_target))
899 nd_na->nd_na_target.s6_addr16[1] = 0;
902 * "tlladdr" indicates NS's condition for adding tlladdr or not.
903 * see nd6_ns_input() for details.
904 * Basically, if NS packet is sent to unicast/anycast addr,
905 * target lladdr option SHOULD NOT be included.
910 * sdl0 != NULL indicates proxy NA. If we do proxy, use
911 * lladdr in sdl0. If we are not proxying (sending NA for
912 * my address) use lladdr configured for the interface.
915 mac = nd6_ifptomac(ifp);
916 else if (sdl0->sa_family == AF_LINK) {
917 struct sockaddr_dl *sdl;
918 sdl = (struct sockaddr_dl *)sdl0;
919 if (sdl->sdl_alen == ifp->if_addrlen)
923 if (tlladdr && mac) {
924 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
925 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1);
927 /* roundup to 8 bytes alignment! */
928 optlen = (optlen + 7) & ~7;
930 m->m_pkthdr.len += optlen;
933 bzero((caddr_t)nd_opt, optlen);
934 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
935 nd_opt->nd_opt_len = optlen >> 3;
936 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
938 flags &= ~ND_NA_FLAG_OVERRIDE;
940 ip6->ip6_plen = htons((u_short)icmp6len);
941 nd_na->nd_na_flags_reserved = flags;
942 nd_na->nd_na_cksum = 0;
944 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len);
946 ip6_output(m, NULL, NULL, 0, &im6o, &outif, NULL);
948 icmp6_ifstat_inc(outif, ifs6_out_msg);
949 icmp6_ifstat_inc(outif, ifs6_out_neighboradvert);
951 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++;
955 nd6_ifptomac(struct ifnet *ifp)
957 switch (ifp->if_type) {
968 return ((caddr_t)(ifp + 1));
975 TAILQ_HEAD(dadq_head, dadq);
977 TAILQ_ENTRY(dadq) dad_list;
978 struct ifaddr *dad_ifa;
979 int dad_count; /* max NS to send */
980 int dad_ns_tcount; /* # of trials to send NS */
981 int dad_ns_ocount; /* NS sent so far */
984 struct callout dad_timer_ch;
987 static struct dadq_head dadq;
988 static int dad_init = 0;
991 nd6_dad_find(struct ifaddr *ifa)
995 TAILQ_FOREACH(dp, &dadq, dad_list) {
996 if (dp->dad_ifa == ifa)
1003 nd6_dad_starttimer(struct dadq *dp, int ticks)
1006 callout_reset(&dp->dad_timer_ch, ticks,
1007 (void (*) (void *))nd6_dad_timer, (void *)dp->dad_ifa);
1011 nd6_dad_stoptimer(struct dadq *dp)
1014 callout_stop(&dp->dad_timer_ch);
1018 * Start Duplicated Address Detection (DAD) for specified interface address.
1021 nd6_dad_start(struct ifaddr *ifa,
1022 int *tick) /* minimum delay ticks for IFF_UP event */
1024 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1033 * If we don't need DAD, don't do it.
1034 * There are several cases:
1035 * - DAD is disabled (ip6_dad_count == 0)
1036 * - the interface address is anycast
1038 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
1040 "nd6_dad_start: called with non-tentative address "
1042 ip6_sprintf(&ia->ia_addr.sin6_addr),
1043 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1046 if (ia->ia6_flags & IN6_IFF_ANYCAST) {
1047 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1050 if (!ip6_dad_count) {
1051 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1055 panic("nd6_dad_start: ifa->ifa_ifp == NULL");
1056 if (!(ifa->ifa_ifp->if_flags & IFF_UP))
1058 if (nd6_dad_find(ifa) != NULL) {
1059 /* DAD already in progress */
1063 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT);
1065 log(LOG_ERR, "nd6_dad_start: memory allocation failed for "
1067 ip6_sprintf(&ia->ia_addr.sin6_addr),
1068 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1071 bzero(dp, sizeof(*dp));
1072 callout_init(&dp->dad_timer_ch);
1073 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list);
1075 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp),
1076 ip6_sprintf(&ia->ia_addr.sin6_addr)));
1079 * Send NS packet for DAD, ip6_dad_count times.
1080 * Note that we must delay the first transmission, if this is the
1081 * first packet to be sent from the interface after interface
1082 * (re)initialization.
1085 IFAREF(ifa); /* just for safety */
1086 dp->dad_count = ip6_dad_count;
1087 dp->dad_ns_icount = dp->dad_na_icount = 0;
1088 dp->dad_ns_ocount = dp->dad_ns_tcount = 0;
1090 nd6_dad_ns_output(dp, ifa);
1091 nd6_dad_starttimer(dp,
1092 nd_ifinfo[ifa->ifa_ifp->if_index].retrans * hz / 1000);
1097 ntick = random() % (MAX_RTR_SOLICITATION_DELAY * hz);
1099 ntick = *tick + random() % (hz / 2);
1101 nd6_dad_starttimer(dp, ntick);
1106 * terminate DAD unconditionally. used for address removals.
1109 nd6_dad_stop(struct ifaddr *ifa)
1115 dp = nd6_dad_find(ifa);
1117 /* DAD wasn't started yet */
1121 nd6_dad_stoptimer(dp);
1123 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1130 nd6_dad_timer(struct ifaddr *ifa)
1133 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1136 s = splnet(); /* XXX */
1140 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n");
1143 dp = nd6_dad_find(ifa);
1145 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n");
1148 if (ia->ia6_flags & IN6_IFF_DUPLICATED) {
1149 log(LOG_ERR, "nd6_dad_timer: called with duplicated address "
1151 ip6_sprintf(&ia->ia_addr.sin6_addr),
1152 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1155 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) {
1156 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address "
1158 ip6_sprintf(&ia->ia_addr.sin6_addr),
1159 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1163 /* timeouted with IFF_{RUNNING,UP} check */
1164 if (dp->dad_ns_tcount > dad_maxtry) {
1165 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n",
1166 if_name(ifa->ifa_ifp)));
1168 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1175 /* Need more checks? */
1176 if (dp->dad_ns_ocount < dp->dad_count) {
1178 * We have more NS to go. Send NS packet for DAD.
1180 nd6_dad_ns_output(dp, ifa);
1181 nd6_dad_starttimer(dp,
1182 nd_ifinfo[ifa->ifa_ifp->if_index].retrans * hz / 1000);
1185 * We have transmitted sufficient number of DAD packets.
1186 * See what we've got.
1192 if (dp->dad_na_icount) {
1194 * the check is in nd6_dad_na_input(),
1200 if (dp->dad_ns_icount) {
1201 #if 0 /* heuristics */
1204 * - we have sent many(?) DAD NS, and
1205 * - the number of NS we sent equals to the
1206 * number of NS we've got, and
1208 * we may have a faulty network card/driver which
1209 * loops back multicasts to myself.
1211 if (3 < dp->dad_count
1212 && dp->dad_ns_icount == dp->dad_count
1213 && dp->dad_na_icount == 0) {
1214 log(LOG_INFO, "DAD questionable for %s(%s): "
1215 "network card loops back multicast?\n",
1216 ip6_sprintf(&ia->ia_addr.sin6_addr),
1217 if_name(ifa->ifa_ifp));
1218 /* XXX consider it a duplicate or not? */
1221 /* We've seen NS, means DAD has failed. */
1225 /* We've seen NS, means DAD has failed. */
1231 /* (*dp) will be freed in nd6_dad_duplicated() */
1233 nd6_dad_duplicated(ifa);
1236 * We are done with DAD. No NA came, no NS came.
1237 * duplicated address found.
1239 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1242 "%s: DAD complete for %s - no duplicates found\n",
1243 if_name(ifa->ifa_ifp),
1244 ip6_sprintf(&ia->ia_addr.sin6_addr)));
1246 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1258 nd6_dad_duplicated(struct ifaddr *ifa)
1260 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1263 dp = nd6_dad_find(ifa);
1265 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n");
1269 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: "
1270 "NS in/out=%d/%d, NA in=%d\n",
1271 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr),
1272 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount);
1274 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1275 ia->ia6_flags |= IN6_IFF_DUPLICATED;
1277 /* We are done with DAD, with duplicated address found. (failure) */
1278 nd6_dad_stoptimer(dp);
1280 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n",
1281 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr));
1282 log(LOG_ERR, "%s: manual intervention required\n",
1283 if_name(ifa->ifa_ifp));
1285 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1292 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa)
1294 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1295 struct ifnet *ifp = ifa->ifa_ifp;
1297 dp->dad_ns_tcount++;
1298 if ((ifp->if_flags & IFF_UP) == 0) {
1300 printf("%s: interface down?\n", if_name(ifp));
1304 if ((ifp->if_flags & IFF_RUNNING) == 0) {
1306 printf("%s: interface not running?\n", if_name(ifp));
1311 dp->dad_ns_ocount++;
1312 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1);
1316 nd6_dad_ns_input(struct ifaddr *ifa)
1318 struct in6_ifaddr *ia;
1320 const struct in6_addr *taddr6;
1325 panic("ifa == NULL in nd6_dad_ns_input");
1327 ia = (struct in6_ifaddr *)ifa;
1329 taddr6 = &ia->ia_addr.sin6_addr;
1331 dp = nd6_dad_find(ifa);
1333 /* Quickhack - completely ignore DAD NS packets */
1334 if (dad_ignore_ns) {
1336 "nd6_dad_ns_input: ignoring DAD NS packet for "
1337 "address %s(%s)\n", ip6_sprintf(taddr6),
1338 if_name(ifa->ifa_ifp)));
1343 * if I'm yet to start DAD, someone else started using this address
1344 * first. I have a duplicate and you win.
1346 if (!dp || dp->dad_ns_ocount == 0)
1349 /* XXX more checks for loopback situation - see nd6_dad_timer too */
1352 dp = NULL; /* will be freed in nd6_dad_duplicated() */
1353 nd6_dad_duplicated(ifa);
1356 * not sure if I got a duplicate.
1357 * increment ns count and see what happens.
1360 dp->dad_ns_icount++;
1365 nd6_dad_na_input(struct ifaddr *ifa)
1370 panic("ifa == NULL in nd6_dad_na_input");
1372 dp = nd6_dad_find(ifa);
1374 dp->dad_na_icount++;
1376 /* remove the address. */
1377 nd6_dad_duplicated(ifa);