1 /* $FreeBSD: src/sys/netinet6/nd6_nbr.c,v 1.4.2.6 2003/01/23 21:06:47 sam Exp $ */
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>
50 #include <sys/mutex.h>
52 #include <sys/thread2.h>
53 #include <sys/mutex2.h>
56 #include <net/if_types.h>
57 #include <net/if_dl.h>
58 #include <net/route.h>
60 #include <netinet/in.h>
61 #include <netinet/in_var.h>
62 #include <netinet6/in6_var.h>
63 #include <netinet/ip6.h>
64 #include <netinet6/ip6_var.h>
65 #include <netinet6/nd6.h>
66 #include <netinet/icmp6.h>
69 #include <netinet6/ipsec.h>
71 #include <netinet6/ipsec6.h>
75 #include <net/net_osdep.h>
78 #include <netinet/ip_carp.h>
82 #define SDL(s) ((struct sockaddr_dl *)s)
85 static struct dadq *nd6_dad_find (struct ifaddr *);
86 static void nd6_dad_starttimer (struct dadq *, int);
87 static void nd6_dad_stoptimer (struct dadq *);
88 static void nd6_dad_timer (struct ifaddr *);
89 static void nd6_dad_ns_output (struct dadq *, struct ifaddr *);
90 static void nd6_dad_ns_input (struct ifaddr *);
91 static void nd6_dad_na_input (struct ifaddr *);
93 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/
94 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */
97 * Input an Neighbor Solicitation Message.
100 * Based on RFC 2462 (duplicated address detection)
103 nd6_ns_input(struct mbuf *m, int off, int icmp6len)
105 struct ifnet *ifp = m->m_pkthdr.rcvif;
106 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
107 struct nd_neighbor_solicit *nd_ns;
108 struct in6_addr saddr6 = ip6->ip6_src;
109 struct in6_addr daddr6 = ip6->ip6_dst;
110 struct in6_addr taddr6;
111 struct in6_addr myaddr6;
113 struct ifaddr *ifa = NULL;
115 int anycast = 0, proxy = 0, tentative = 0;
117 union nd_opts ndopts;
118 struct sockaddr_dl *proxydl = NULL;
120 #ifndef PULLDOWN_TEST
121 IP6_EXTHDR_CHECK(m, off, icmp6len,);
122 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off);
124 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len);
126 icmp6stat.icp6s_tooshort++;
130 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */
131 taddr6 = nd_ns->nd_ns_target;
133 if (ip6->ip6_hlim != 255) {
135 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n",
136 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src),
137 ip6_sprintf(&ip6->ip6_dst), if_name(ifp)));
141 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
142 /* dst has to be solicited node multicast address. */
143 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL
144 /* don't check ifindex portion */
145 && daddr6.s6_addr32[1] == 0
146 && daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE
147 && daddr6.s6_addr8[12] == 0xff) {
150 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
151 "(wrong ip6 dst)\n"));
156 * Make sure the source address is from a neighbor's address.
158 if (in6ifa_ifplocaladdr(ifp, &saddr6) == NULL) {
159 nd6log((LOG_INFO, "nd6_ns_input: "
160 "NS packet from non-neighbor\n"));
165 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
166 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n"));
170 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6))
171 taddr6.s6_addr16[1] = htons(ifp->if_index);
173 icmp6len -= sizeof(*nd_ns);
174 nd6_option_init(nd_ns + 1, icmp6len, &ndopts);
175 if (nd6_options(&ndopts) < 0) {
177 "nd6_ns_input: invalid ND option, ignored\n"));
178 /* nd6_options have incremented stats */
182 if (ndopts.nd_opts_src_lladdr) {
183 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
184 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
187 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) {
188 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
189 "(link-layer address option)\n"));
194 * Attaching target link-layer address to the NA?
197 * NS IP dst is unicast/anycast MUST NOT add
198 * NS IP dst is solicited-node multicast MUST add
200 * In implementation, we add target link-layer address by default.
201 * We do not add one in MUST NOT cases.
203 #if 0 /* too much! */
204 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6);
205 if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST))
209 if (!IN6_IS_ADDR_MULTICAST(&daddr6))
215 * Target address (taddr6) must be either:
216 * (1) Valid unicast/anycast address for my receiving interface,
217 * (2) Unicast address for which I'm offering proxy service, or
218 * (3) "tentative" address on which DAD is being performed.
220 /* (1) and (3) check. */
223 ifa = carp_iamatch6(ifp->if_carp, &taddr6);
225 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
227 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
233 struct sockaddr_in6 tsin6;
235 bzero(&tsin6, sizeof tsin6);
236 tsin6.sin6_len = sizeof(struct sockaddr_in6);
237 tsin6.sin6_family = AF_INET6;
238 tsin6.sin6_addr = taddr6;
240 rt = rtpurelookup((struct sockaddr *)&tsin6);
241 if (rt != NULL && (rt->rt_flags & RTF_ANNOUNCE) &&
242 rt->rt_gateway->sa_family == AF_LINK) {
244 * proxy NDP for single entry
246 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp,
247 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
250 proxydl = SDL(rt->rt_gateway);
258 * We've got an NS packet, and we don't have that adddress
259 * assigned for us. We MUST silently ignore it.
264 myaddr6 = *IFA_IN6(ifa);
265 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST;
266 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE;
267 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED)
270 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
272 "nd6_ns_input: lladdrlen mismatch for %s "
273 "(if %d, NS packet %d)\n",
274 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2));
278 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) {
280 "nd6_ns_input: duplicate IP6 address %s\n",
281 ip6_sprintf(&saddr6)));
286 * We have neighbor solicitation packet, with target address equals to
287 * one of my tentative address.
289 * src addr how to process?
291 * multicast of course, invalid (rejected in ip6_input)
292 * unicast somebody is doing address resolution -> ignore
293 * unspec dup address detection
295 * The processing is defined in RFC 2462.
299 * If source address is unspecified address, it is for
300 * duplicated address detection.
302 * If not, the packet is for addess resolution;
303 * silently ignore it.
305 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6))
306 nd6_dad_ns_input(ifa);
312 * If the source address is unspecified address, entries must not
313 * be created or updated.
314 * It looks that sender is performing DAD. Output NA toward
315 * all-node multicast address, to tell the sender that I'm using
317 * S bit ("solicited") must be zero.
319 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
320 saddr6 = kin6addr_linklocal_allnodes;
321 saddr6.s6_addr16[1] = htons(ifp->if_index);
322 nd6_na_output(ifp, &saddr6, &taddr6,
323 ((anycast || proxy || !tlladdr)
324 ? 0 : ND_NA_FLAG_OVERRIDE)
325 | (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0),
326 tlladdr, (struct sockaddr *)proxydl);
330 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_NEIGHBOR_SOLICIT, 0);
332 nd6_na_output(ifp, &saddr6, &taddr6,
333 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE)
334 | (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0)
335 | ND_NA_FLAG_SOLICITED,
336 tlladdr, (struct sockaddr *)proxydl);
342 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", ip6_sprintf(&saddr6)));
343 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", ip6_sprintf(&daddr6)));
344 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", ip6_sprintf(&taddr6)));
345 icmp6stat.icp6s_badns++;
350 * Output an Neighbor Solicitation Message. Caller specifies:
351 * - ICMP6 header source IP6 address
352 * - ND6 header target IP6 address
353 * - ND6 header source datalink address
356 * Based on RFC 2462 (duplicated address detection)
359 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6,
360 const struct in6_addr *taddr6,
361 struct llinfo_nd6 *ln, /* for source address determination */
362 int dad) /* duplicated address detection */
366 struct nd_neighbor_solicit *nd_ns;
367 struct in6_ifaddr *ia = NULL;
368 struct ip6_moptions im6o;
372 struct ifnet *outif = NULL;
374 if (IN6_IS_ADDR_MULTICAST(taddr6))
377 /* estimate the size of message */
378 maxlen = sizeof(*ip6) + sizeof(*nd_ns);
379 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
380 if (max_linkhdr + maxlen >= MCLBYTES) {
382 kprintf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES "
383 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
388 m = m_getb(max_linkhdr + maxlen, MB_DONTWAIT, MT_DATA, M_PKTHDR);
392 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) {
393 m->m_flags |= M_MCAST;
394 im6o.im6o_multicast_ifp = ifp;
395 im6o.im6o_multicast_hlim = 255;
396 im6o.im6o_multicast_loop = 0;
399 icmp6len = sizeof(*nd_ns);
400 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len;
401 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
403 /* fill neighbor solicitation packet */
404 ip6 = mtod(m, struct ip6_hdr *);
406 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
407 ip6->ip6_vfc |= IPV6_VERSION;
408 /* ip6->ip6_plen will be set later */
409 ip6->ip6_nxt = IPPROTO_ICMPV6;
412 ip6->ip6_dst = *daddr6;
414 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
415 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index);
416 ip6->ip6_dst.s6_addr32[1] = 0;
417 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE;
418 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3];
419 ip6->ip6_dst.s6_addr8[12] = 0xff;
422 #if 0 /* KAME way, exact address scope match */
424 * Select a source whose scope is the same as that of the dest.
425 * Typically, the dest is link-local solicitation multicast
426 * (i.e. neighbor discovery) or link-local/global unicast
427 * (i.e. neighbor un-reachability detection).
429 ia = in6_ifawithifp(ifp, &ip6->ip6_dst);
434 ip6->ip6_src = ia->ia_addr.sin6_addr;
435 #else /* spec-wise correct */
438 * "If the source address of the packet prompting the
439 * solicitation is the same as one of the addresses assigned
440 * to the outgoing interface, that address SHOULD be placed
441 * in the IP Source Address of the outgoing solicitation.
442 * Otherwise, any one of the addresses assigned to the
443 * interface should be used."
445 * We use the source address for the prompting packet
447 * - saddr6 is given from the caller (by giving "ln"), and
448 * - saddr6 belongs to the outgoing interface.
449 * Otherwise, we perform a scope-wise match.
451 struct ip6_hdr *hip6; /* hold ip6 */
452 struct in6_addr *saddr6;
454 if (ln && ln->ln_hold) {
455 hip6 = mtod(ln->ln_hold, struct ip6_hdr *);
457 if (sizeof(*hip6) < ln->ln_hold->m_len)
458 saddr6 = &hip6->ip6_src;
463 if (saddr6 && in6ifa_ifpwithaddr(ifp, saddr6))
464 bcopy(saddr6, &ip6->ip6_src, sizeof(*saddr6));
466 ia = in6_ifawithifp(ifp, &ip6->ip6_dst);
471 ip6->ip6_src = ia->ia_addr.sin6_addr;
476 * Source address for DAD packet must always be IPv6
477 * unspecified address. (0::0)
479 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src));
481 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1);
482 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT;
483 nd_ns->nd_ns_code = 0;
484 nd_ns->nd_ns_reserved = 0;
485 nd_ns->nd_ns_target = *taddr6;
487 if (IN6_IS_SCOPE_LINKLOCAL(&nd_ns->nd_ns_target))
488 nd_ns->nd_ns_target.s6_addr16[1] = 0;
491 * Add source link-layer address option.
493 * spec implementation
495 * DAD packet MUST NOT do not add the option
496 * there's no link layer address:
497 * impossible do not add the option
498 * there's link layer address:
499 * Multicast NS MUST add one add the option
500 * Unicast NS SHOULD add one add the option
502 if (!dad && (mac = nd6_ifptomac(ifp))) {
503 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
504 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
505 /* 8 byte alignments... */
506 optlen = (optlen + 7) & ~7;
508 m->m_pkthdr.len += optlen;
511 bzero((caddr_t)nd_opt, optlen);
512 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR;
513 nd_opt->nd_opt_len = optlen >> 3;
514 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
517 ip6->ip6_plen = htons((u_short)icmp6len);
518 nd_ns->nd_ns_cksum = 0;
520 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len);
522 ip6_output(m, NULL, NULL, dad ? IPV6_DADOUTPUT : 0, &im6o, &outif, NULL);
524 icmp6_ifstat_inc(outif, ifs6_out_msg);
525 icmp6_ifstat_inc(outif, ifs6_out_neighborsolicit);
527 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++;
531 * Neighbor advertisement input handling.
534 * Based on RFC 2462 (duplicated address detection)
536 * the following items are not implemented yet:
537 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
538 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
541 nd6_na_input(struct mbuf *m, int off, int icmp6len)
543 struct ifnet *ifp = m->m_pkthdr.rcvif;
544 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
545 struct nd_neighbor_advert *nd_na;
546 struct in6_addr saddr6 = ip6->ip6_src;
547 struct in6_addr daddr6 = ip6->ip6_dst;
548 struct in6_addr taddr6;
556 struct llinfo_nd6 *ln;
558 struct sockaddr_dl *sdl;
559 union nd_opts ndopts;
561 if (ip6->ip6_hlim != 255) {
563 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n",
564 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src),
565 ip6_sprintf(&ip6->ip6_dst), if_name(ifp)));
569 #ifndef PULLDOWN_TEST
570 IP6_EXTHDR_CHECK(m, off, icmp6len,);
571 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off);
573 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len);
575 icmp6stat.icp6s_tooshort++;
579 taddr6 = nd_na->nd_na_target;
580 flags = nd_na->nd_na_flags_reserved;
581 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0);
582 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0);
583 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0);
585 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6))
586 taddr6.s6_addr16[1] = htons(ifp->if_index);
588 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
590 "nd6_na_input: invalid target address %s\n",
591 ip6_sprintf(&taddr6)));
594 if (IN6_IS_ADDR_MULTICAST(&daddr6))
597 "nd6_na_input: a solicited adv is multicasted\n"));
601 icmp6len -= sizeof(*nd_na);
602 nd6_option_init(nd_na + 1, icmp6len, &ndopts);
603 if (nd6_options(&ndopts) < 0) {
605 "nd6_na_input: invalid ND option, ignored\n"));
606 /* nd6_options have incremented stats */
610 if (ndopts.nd_opts_tgt_lladdr) {
611 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
612 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
615 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
618 * Target address matches one of my interface address.
620 * If my address is tentative, this means that there's somebody
621 * already using the same address as mine. This indicates DAD failure.
622 * This is defined in RFC 2462.
624 * Otherwise, process as defined in RFC 2461.
627 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) {
628 nd6_dad_na_input(ifa);
632 /* Just for safety, maybe unnecessary. */
635 "nd6_na_input: duplicate IP6 address %s\n",
636 ip6_sprintf(&taddr6));
641 * Make sure the source address is from a neighbor's address.
643 if (in6ifa_ifplocaladdr(ifp, &saddr6) == NULL) {
644 nd6log((LOG_INFO, "nd6_na_input: "
645 "NA packet from non-neighbor\n"));
649 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
651 "nd6_na_input: lladdrlen mismatch for %s "
652 "(if %d, NA packet %d)\n",
653 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2));
658 * If no neighbor cache entry is found, NA SHOULD silently be discarded.
660 rt = nd6_lookup(&taddr6, 0, ifp);
662 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) ||
663 ((sdl = SDL(rt->rt_gateway)) == NULL))
666 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
668 * If the link-layer has address, and no lladdr option came,
669 * discard the packet.
671 if (ifp->if_addrlen && !lladdr)
675 * Record link-layer address, and update the state.
677 sdl->sdl_alen = ifp->if_addrlen;
678 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
680 ln->ln_state = ND6_LLINFO_REACHABLE;
683 ln->ln_expire = time_second +
684 ND_IFINFO(rt->rt_ifp)->reachable;
686 ln->ln_state = ND6_LLINFO_STALE;
687 ln->ln_expire = time_second + nd6_gctimer;
689 if ((ln->ln_router = is_router) != 0) {
691 * This means a router's state has changed from
692 * non-reachable to probably reachable, and might
693 * affect the status of associated prefixes..
695 pfxlist_onlink_check();
701 * Check if the link-layer address has changed or not.
707 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen))
716 * This is VERY complex. Look at it with care.
718 * override solicit lladdr llchange action
723 * 0 0 y y (1) REACHABLE->STALE
724 * 0 1 n -- (2c) *->REACHABLE
725 * 0 1 y n (2b) L *->REACHABLE
726 * 0 1 y y (1) REACHABLE->STALE
729 * 1 0 y y (2a) L *->STALE
730 * 1 1 n -- (2a) *->REACHABLE
731 * 1 1 y n (2a) L *->REACHABLE
732 * 1 1 y y (2a) L *->REACHABLE
734 if (!is_override && (lladdr && llchange)) { /* (1) */
736 * If state is REACHABLE, make it STALE.
737 * no other updates should be done.
739 if (ln->ln_state == ND6_LLINFO_REACHABLE) {
740 ln->ln_state = ND6_LLINFO_STALE;
741 ln->ln_expire = time_second + nd6_gctimer;
744 } else if (is_override /* (2a) */
745 || (!is_override && (lladdr && !llchange)) /* (2b) */
746 || !lladdr) { /* (2c) */
748 * Update link-local address, if any.
751 sdl->sdl_alen = ifp->if_addrlen;
752 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
756 * If solicited, make the state REACHABLE.
757 * If not solicited and the link-layer address was
758 * changed, make it STALE.
761 ln->ln_state = ND6_LLINFO_REACHABLE;
764 ln->ln_expire = time_second +
765 ND_IFINFO(ifp)->reachable;
768 if (lladdr && llchange) {
769 ln->ln_state = ND6_LLINFO_STALE;
770 ln->ln_expire = time_second + nd6_gctimer;
775 if (ln->ln_router && !is_router) {
777 * The peer dropped the router flag.
778 * Remove the sender from the Default Router List and
779 * update the Destination Cache entries.
781 struct nd_defrouter *dr;
782 struct in6_addr *in6;
784 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr;
787 * Lock to protect the default router list.
788 * XXX: this might be unnecessary, since this function
789 * is only called under the network software interrupt
790 * context. However, we keep it just for safety.
793 dr = defrouter_lookup(in6, rt->rt_ifp);
796 mtx_unlock(&nd6_mtx);
798 if (dr == NULL && !ip6_forwarding && ip6_accept_rtadv) {
800 * Even if the neighbor is not in the default
801 * router list, the neighbor may be used
802 * as a next hop for some destinations
803 * (e.g. redirect case). So we must
804 * call rt6_flush explicitly.
806 rt6_flush(&ip6->ip6_src, rt->rt_ifp);
809 ln->ln_router = is_router;
811 rt->rt_flags &= ~RTF_REJECT;
815 * we assume ifp is not a loopback here, so just set the 2nd
816 * argument as the 1st one.
818 nd6_output(ifp, ifp, ln->ln_hold,
819 (struct sockaddr_in6 *)rt_key(rt), rt);
828 icmp6stat.icp6s_badna++;
833 * Neighbor advertisement output handling.
837 * the following items are not implemented yet:
838 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
839 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
842 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6,
843 const struct in6_addr *taddr6, u_long flags,
844 int tlladdr, /* 1 if include target link-layer address */
845 struct sockaddr *sdl0) /* sockaddr_dl (= proxy NA) or NULL */
849 struct nd_neighbor_advert *nd_na;
850 struct in6_ifaddr *ia = NULL;
851 struct ip6_moptions im6o;
855 struct ifnet *outif = NULL;
857 /* estimate the size of message */
858 maxlen = sizeof(*ip6) + sizeof(*nd_na);
859 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
860 if (max_linkhdr + maxlen >= MCLBYTES) {
862 kprintf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES "
863 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
868 m = m_getb(max_linkhdr + maxlen, MB_DONTWAIT, MT_DATA, M_PKTHDR);
872 if (IN6_IS_ADDR_MULTICAST(daddr6)) {
873 m->m_flags |= M_MCAST;
874 im6o.im6o_multicast_ifp = ifp;
875 im6o.im6o_multicast_hlim = 255;
876 im6o.im6o_multicast_loop = 0;
879 icmp6len = sizeof(*nd_na);
880 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len;
881 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
883 /* fill neighbor advertisement packet */
884 ip6 = mtod(m, struct ip6_hdr *);
886 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
887 ip6->ip6_vfc |= IPV6_VERSION;
888 ip6->ip6_nxt = IPPROTO_ICMPV6;
890 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) {
892 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
893 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index);
894 ip6->ip6_dst.s6_addr32[1] = 0;
895 ip6->ip6_dst.s6_addr32[2] = 0;
896 ip6->ip6_dst.s6_addr32[3] = IPV6_ADDR_INT32_ONE;
897 flags &= ~ND_NA_FLAG_SOLICITED;
899 ip6->ip6_dst = *daddr6;
902 * Select a source whose scope is the same as that of the dest.
904 ia = in6_ifawithifp(ifp, &ip6->ip6_dst);
909 ip6->ip6_src = ia->ia_addr.sin6_addr;
910 nd_na = (struct nd_neighbor_advert *)(ip6 + 1);
911 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT;
912 nd_na->nd_na_code = 0;
913 nd_na->nd_na_target = *taddr6;
914 if (IN6_IS_SCOPE_LINKLOCAL(&nd_na->nd_na_target))
915 nd_na->nd_na_target.s6_addr16[1] = 0;
918 * "tlladdr" indicates NS's condition for adding tlladdr or not.
919 * see nd6_ns_input() for details.
920 * Basically, if NS packet is sent to unicast/anycast addr,
921 * target lladdr option SHOULD NOT be included.
926 * sdl0 != NULL indicates proxy NA. If we do proxy, use
927 * lladdr in sdl0. If we are not proxying (sending NA for
928 * my address) use lladdr configured for the interface.
933 mac = carp_macmatch6(ifp->if_carp, m, taddr6);
935 mac = nd6_ifptomac(ifp);
937 mac = nd6_ifptomac(ifp);
939 } else if (sdl0->sa_family == AF_LINK) {
940 struct sockaddr_dl *sdl;
941 sdl = (struct sockaddr_dl *)sdl0;
942 if (sdl->sdl_alen == ifp->if_addrlen)
947 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
948 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1);
950 /* roundup to 8 bytes alignment! */
951 optlen = (optlen + 7) & ~7;
953 m->m_pkthdr.len += optlen;
956 bzero((caddr_t)nd_opt, optlen);
957 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
958 nd_opt->nd_opt_len = optlen >> 3;
959 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
961 flags &= ~ND_NA_FLAG_OVERRIDE;
963 ip6->ip6_plen = htons((u_short)icmp6len);
964 nd_na->nd_na_flags_reserved = flags;
965 nd_na->nd_na_cksum = 0;
967 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len);
969 ip6_output(m, NULL, NULL, 0, &im6o, &outif, NULL);
971 icmp6_ifstat_inc(outif, ifs6_out_msg);
972 icmp6_ifstat_inc(outif, ifs6_out_neighboradvert);
974 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++;
978 nd6_ifptomac(struct ifnet *ifp)
980 switch (ifp->if_type) {
992 return ((caddr_t)(ifp + 1));
999 TAILQ_HEAD(dadq_head, dadq);
1001 TAILQ_ENTRY(dadq) dad_list;
1002 struct ifaddr *dad_ifa;
1003 int dad_count; /* max NS to send */
1004 int dad_ns_tcount; /* # of trials to send NS */
1005 int dad_ns_ocount; /* NS sent so far */
1008 struct callout dad_timer_ch;
1011 static struct dadq_head dadq;
1012 static int dad_init = 0;
1014 static struct dadq *
1015 nd6_dad_find(struct ifaddr *ifa)
1019 TAILQ_FOREACH(dp, &dadq, dad_list) {
1020 if (dp->dad_ifa == ifa)
1027 nd6_dad_starttimer(struct dadq *dp, int ticks)
1030 callout_reset(&dp->dad_timer_ch, ticks,
1031 (void (*) (void *))nd6_dad_timer, (void *)dp->dad_ifa);
1035 nd6_dad_stoptimer(struct dadq *dp)
1038 callout_stop(&dp->dad_timer_ch);
1042 * Start Duplicated Address Detection (DAD) for specified interface address.
1045 nd6_dad_start(struct ifaddr *ifa,
1046 int *tick) /* minimum delay ticks for IFF_UP event */
1048 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1057 * If we don't need DAD, don't do it.
1058 * There are several cases:
1059 * - DAD is disabled (ip6_dad_count == 0)
1060 * - the interface address is anycast
1062 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
1064 "nd6_dad_start: called with non-tentative address "
1066 ip6_sprintf(&ia->ia_addr.sin6_addr),
1067 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1070 if (ia->ia6_flags & IN6_IFF_ANYCAST) {
1071 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1074 if (!ip6_dad_count) {
1075 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1079 panic("nd6_dad_start: ifa->ifa_ifp == NULL");
1080 if (!(ifa->ifa_ifp->if_flags & IFF_UP))
1082 if (nd6_dad_find(ifa) != NULL) {
1083 /* DAD already in progress */
1087 dp = kmalloc(sizeof(*dp), M_IP6NDP, M_NOWAIT | M_ZERO);
1089 log(LOG_ERR, "nd6_dad_start: memory allocation failed for "
1091 ip6_sprintf(&ia->ia_addr.sin6_addr),
1092 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1095 callout_init(&dp->dad_timer_ch);
1096 TAILQ_INSERT_TAIL(&dadq, dp, dad_list);
1098 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp),
1099 ip6_sprintf(&ia->ia_addr.sin6_addr)));
1102 * Send NS packet for DAD, ip6_dad_count times.
1103 * Note that we must delay the first transmission, if this is the
1104 * first packet to be sent from the interface after interface
1105 * (re)initialization.
1108 _IFAREF(ifa, 0); /* just for safety */
1109 dp->dad_count = ip6_dad_count;
1110 dp->dad_ns_icount = dp->dad_na_icount = 0;
1111 dp->dad_ns_ocount = dp->dad_ns_tcount = 0;
1113 nd6_dad_ns_output(dp, ifa);
1114 nd6_dad_starttimer(dp,
1115 ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1120 ntick = krandom() % (MAX_RTR_SOLICITATION_DELAY * hz);
1122 ntick = *tick + krandom() % (hz / 2);
1124 nd6_dad_starttimer(dp, ntick);
1129 * terminate DAD unconditionally. used for address removals.
1132 nd6_dad_stop(struct ifaddr *ifa)
1138 dp = nd6_dad_find(ifa);
1140 /* DAD wasn't started yet */
1144 nd6_dad_stoptimer(dp);
1146 TAILQ_REMOVE(&dadq, dp, dad_list);
1147 kfree(dp, M_IP6NDP);
1153 nd6_dad_timer(struct ifaddr *ifa)
1155 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1162 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n");
1165 dp = nd6_dad_find(ifa);
1167 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n");
1170 if (ia->ia6_flags & IN6_IFF_DUPLICATED) {
1171 log(LOG_ERR, "nd6_dad_timer: called with duplicated address "
1173 ip6_sprintf(&ia->ia_addr.sin6_addr),
1174 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1177 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
1178 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address "
1180 ip6_sprintf(&ia->ia_addr.sin6_addr),
1181 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1185 /* timeouted with IFF_{RUNNING,UP} check */
1186 if (dp->dad_ns_tcount > dad_maxtry) {
1187 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n",
1188 if_name(ifa->ifa_ifp)));
1190 TAILQ_REMOVE(&dadq, dp, dad_list);
1191 kfree(dp, M_IP6NDP);
1197 /* Need more checks? */
1198 if (dp->dad_ns_ocount < dp->dad_count) {
1200 * We have more NS to go. Send NS packet for DAD.
1202 nd6_dad_ns_output(dp, ifa);
1203 nd6_dad_starttimer(dp,
1204 ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1207 * We have transmitted sufficient number of DAD packets.
1208 * See what we've got.
1214 if (dp->dad_na_icount) {
1216 * the check is in nd6_dad_na_input(),
1222 if (dp->dad_ns_icount) {
1223 #if 0 /* heuristics */
1226 * - we have sent many(?) DAD NS, and
1227 * - the number of NS we sent equals to the
1228 * number of NS we've got, and
1230 * we may have a faulty network card/driver which
1231 * loops back multicasts to myself.
1233 if (3 < dp->dad_count
1234 && dp->dad_ns_icount == dp->dad_count
1235 && dp->dad_na_icount == 0) {
1236 log(LOG_INFO, "DAD questionable for %s(%s): "
1237 "network card loops back multicast?\n",
1238 ip6_sprintf(&ia->ia_addr.sin6_addr),
1239 if_name(ifa->ifa_ifp));
1240 /* XXX consider it a duplicate or not? */
1243 /* We've seen NS, means DAD has failed. */
1247 /* We've seen NS, means DAD has failed. */
1253 /* (*dp) will be freed in nd6_dad_duplicated() */
1255 nd6_dad_duplicated(ifa);
1258 * We are done with DAD. No NA came, no NS came.
1259 * duplicated address found.
1261 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1264 "%s: DAD complete for %s - no duplicates found\n",
1265 if_name(ifa->ifa_ifp),
1266 ip6_sprintf(&ia->ia_addr.sin6_addr)));
1268 TAILQ_REMOVE(&dadq, dp, dad_list);
1269 kfree(dp, M_IP6NDP);
1276 mtx_unlock(&nd6_mtx);
1280 nd6_dad_duplicated(struct ifaddr *ifa)
1282 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1285 dp = nd6_dad_find(ifa);
1287 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n");
1291 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: "
1292 "NS in/out=%d/%d, NA in=%d\n",
1293 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr),
1294 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount);
1296 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1297 ia->ia6_flags |= IN6_IFF_DUPLICATED;
1299 /* We are done with DAD, with duplicated address found. (failure) */
1300 nd6_dad_stoptimer(dp);
1302 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n",
1303 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr));
1304 log(LOG_ERR, "%s: manual intervention required\n",
1305 if_name(ifa->ifa_ifp));
1307 TAILQ_REMOVE(&dadq, dp, dad_list);
1308 kfree(dp, M_IP6NDP);
1314 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa)
1316 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1317 struct ifnet *ifp = ifa->ifa_ifp;
1319 dp->dad_ns_tcount++;
1320 if (!(ifp->if_flags & IFF_UP)) {
1322 kprintf("%s: interface down?\n", if_name(ifp));
1326 if (!(ifp->if_flags & IFF_RUNNING)) {
1328 kprintf("%s: interface not running?\n", if_name(ifp));
1333 dp->dad_ns_ocount++;
1334 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1);
1338 nd6_dad_ns_input(struct ifaddr *ifa)
1340 struct in6_ifaddr *ia;
1341 const struct in6_addr *taddr6;
1346 panic("ifa == NULL in nd6_dad_ns_input");
1348 ia = (struct in6_ifaddr *)ifa;
1349 taddr6 = &ia->ia_addr.sin6_addr;
1351 dp = nd6_dad_find(ifa);
1353 /* Quickhack - completely ignore DAD NS packets */
1354 if (dad_ignore_ns) {
1356 "nd6_dad_ns_input: ignoring DAD NS packet for "
1357 "address %s(%s)\n", ip6_sprintf(taddr6),
1358 if_name(ifa->ifa_ifp)));
1363 * if I'm yet to start DAD, someone else started using this address
1364 * first. I have a duplicate and you win.
1366 if (!dp || dp->dad_ns_ocount == 0)
1369 /* XXX more checks for loopback situation - see nd6_dad_timer too */
1372 dp = NULL; /* will be freed in nd6_dad_duplicated() */
1373 nd6_dad_duplicated(ifa);
1376 * not sure if I got a duplicate.
1377 * increment ns count and see what happens.
1380 dp->dad_ns_icount++;
1385 nd6_dad_na_input(struct ifaddr *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);