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>
59 #include <net/netisr2.h>
60 #include <net/netmsg2.h>
62 #include <netinet/in.h>
63 #include <netinet/in_var.h>
64 #include <netinet6/in6_var.h>
65 #include <netinet/ip6.h>
66 #include <netinet6/ip6_var.h>
67 #include <netinet6/nd6.h>
68 #include <netinet/icmp6.h>
71 #include <netinet6/ipsec.h>
73 #include <netinet6/ipsec6.h>
77 #include <net/net_osdep.h>
80 #include <netinet/ip_carp.h>
84 #define SDL(s) ((struct sockaddr_dl *)s)
87 static struct dadq *nd6_dad_find(struct ifaddr *);
88 static void nd6_dad_starttimer(struct dadq *, int);
89 static void nd6_dad_stoptimer(struct dadq *);
90 static void nd6_dad_timer(void *);
91 static void nd6_dad_timer_handler(netmsg_t);
92 static void nd6_dad_ns_output(struct dadq *);
93 static void nd6_dad_ns_input(struct ifaddr *);
94 static void nd6_dad_na_input(struct ifaddr *);
95 static struct dadq *nd6_dad_create(struct ifaddr *);
96 static void nd6_dad_destroy(struct dadq *);
97 static void nd6_dad_duplicated(struct ifaddr *);
99 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/
100 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */
103 * Input an Neighbor Solicitation Message.
106 * Based on RFC 2462 (duplicated address detection)
109 nd6_ns_input(struct mbuf *m, int off, int icmp6len)
111 struct ifnet *ifp = m->m_pkthdr.rcvif;
112 struct ifnet *cmpifp;
113 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
114 struct nd_neighbor_solicit *nd_ns;
115 struct in6_addr saddr6 = ip6->ip6_src;
116 struct in6_addr daddr6 = ip6->ip6_dst;
117 struct in6_addr taddr6;
118 struct in6_addr myaddr6;
120 struct ifaddr *ifa = NULL;
122 int anycast = 0, proxy = 0, tentative = 0;
124 union nd_opts ndopts;
125 struct sockaddr_dl *proxydl = NULL;
128 * Collapse interfaces to the bridge for comparison and
129 * mac (llinfo) purposes.
133 cmpifp = ifp->if_bridge;
135 #ifndef PULLDOWN_TEST
136 IP6_EXTHDR_CHECK(m, off, icmp6len,);
137 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off);
139 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len);
141 icmp6stat.icp6s_tooshort++;
145 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */
146 taddr6 = nd_ns->nd_ns_target;
148 if (ip6->ip6_hlim != 255) {
150 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n",
151 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src),
152 ip6_sprintf(&ip6->ip6_dst), if_name(ifp)));
156 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
157 /* dst has to be solicited node multicast address. */
158 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL
159 /* don't check ifindex portion */
160 && daddr6.s6_addr32[1] == 0
161 && daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE
162 && daddr6.s6_addr8[12] == 0xff) {
165 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
166 "(wrong ip6 dst)\n"));
169 } else if (!nd6_onlink_ns_rfc4861) {
171 * Make sure the source address is from a neighbor's address.
173 * XXX probably only need to check cmpifp.
175 if (in6ifa_ifplocaladdr(cmpifp, &saddr6) == NULL &&
176 in6ifa_ifplocaladdr(ifp, &saddr6) == NULL) {
177 nd6log((LOG_INFO, "nd6_ns_input: "
178 "NS packet from non-neighbor\n"));
183 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
184 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n"));
188 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6))
189 taddr6.s6_addr16[1] = htons(ifp->if_index);
191 icmp6len -= sizeof(*nd_ns);
192 nd6_option_init(nd_ns + 1, icmp6len, &ndopts);
193 if (nd6_options(&ndopts) < 0) {
195 "nd6_ns_input: invalid ND option, ignored\n"));
196 /* nd6_options have incremented stats */
200 if (ndopts.nd_opts_src_lladdr) {
201 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
202 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
205 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) {
206 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
207 "(link-layer address option)\n"));
212 * Attaching target link-layer address to the NA?
215 * NS IP dst is unicast/anycast MUST NOT add
216 * NS IP dst is solicited-node multicast MUST add
218 * In implementation, we add target link-layer address by default.
219 * We do not add one in MUST NOT cases.
221 #if 0 /* too much! */
222 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6);
223 if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST))
227 if (!IN6_IS_ADDR_MULTICAST(&daddr6))
233 * Target address (taddr6) must be either:
234 * (1) Valid unicast/anycast address for my receiving interface.
235 * (2) Unicast or anycast address for which I'm offering proxy
237 * (3) "tentative" address on which DAD is being performed.
239 /* (1) and (3) check. */
242 ifa = carp_iamatch6(ifp->if_carp, &taddr6);
244 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
246 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
250 * (2) Check proxying. Requires ip6_forwarding to be turned on.
252 * If the packet is anycast the target route must be on a
253 * different interface because the anycast will get anything
254 * on the current interface.
256 * If the packet is unicast the target route may be on the
257 * same interface. If the gateway is a (typically manually
258 * configured) link address we can directly offer it.
259 * XXX for now we don't do this but instead offer ours and
262 * WARNING! Since this is a subnet proxy the interface proxying
263 * the ND6 must be in promiscuous mode or it will not see the
264 * solicited multicast requests for various hosts being proxied.
266 * WARNING! Since this is a subnet proxy we have to treat bridge
267 * interfaces as being the bridge itself so we do not proxy-nd6
268 * between bridge interfaces (which are effectively switched).
270 * (In the specific-host-proxy case via RTF_ANNOUNCE, which is
271 * a bitch to configure, a specific multicast route is already
272 * added for that host <-- NOT RECOMMENDED).
274 if (!ifa && ip6_forwarding) {
276 struct sockaddr_in6 tsin6;
279 bzero(&tsin6, sizeof tsin6);
280 tsin6.sin6_len = sizeof(struct sockaddr_in6);
281 tsin6.sin6_family = AF_INET6;
282 tsin6.sin6_addr = taddr6;
284 rt = rtpurelookup((struct sockaddr *)&tsin6);
285 rtifp = rt ? rt->rt_ifp : NULL;
286 if (rtifp && rtifp->if_bridge)
287 rtifp = rtifp->if_bridge;
291 (cmpifp == rtifp && (m->m_flags & M_MCAST) == 0))
293 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(cmpifp,
294 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
296 "nd6_ns_input: nd6 proxy %s(%s)<-%s ifa %p\n",
297 if_name(cmpifp), if_name(ifp),
298 if_name(rtifp), ifa));
302 * Manual link address on same interface
303 * w/announce flag will proxy-arp using
304 * target mac, else our mac is used.
306 if (cmpifp == rtifp &&
307 (rt->rt_flags & RTF_ANNOUNCE) &&
308 rt->rt_gateway->sa_family == AF_LINK) {
309 proxydl = SDL(rt->rt_gateway);
318 * We've got an NS packet, and we don't have that adddress
319 * assigned for us. We MUST silently ignore it.
324 myaddr6 = *IFA_IN6(ifa);
325 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST;
326 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE;
327 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED)
330 if (lladdr && ((cmpifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
332 "nd6_ns_input: lladdrlen mismatch for %s "
333 "(if %d, NS packet %d)\n",
334 ip6_sprintf(&taddr6), cmpifp->if_addrlen, lladdrlen - 2));
338 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) {
340 "nd6_ns_input: duplicate IP6 address %s\n",
341 ip6_sprintf(&saddr6)));
346 * We have neighbor solicitation packet, with target address equals to
347 * one of my tentative address.
349 * src addr how to process?
351 * multicast of course, invalid (rejected in ip6_input)
352 * unicast somebody is doing address resolution -> ignore
353 * unspec dup address detection
355 * The processing is defined in RFC 2462.
359 * If source address is unspecified address, it is for
360 * duplicated address detection.
362 * If not, the packet is for addess resolution;
363 * silently ignore it.
365 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6))
366 nd6_dad_ns_input(ifa);
372 * If the source address is unspecified address, entries must not
373 * be created or updated.
374 * It looks that sender is performing DAD. Output NA toward
375 * all-node multicast address, to tell the sender that I'm using
377 * S bit ("solicited") must be zero.
379 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
380 saddr6 = kin6addr_linklocal_allnodes;
381 saddr6.s6_addr16[1] = htons(cmpifp->if_index);
382 nd6_na_output(cmpifp, &saddr6, &taddr6,
383 ((anycast || proxy || !tlladdr)
384 ? 0 : ND_NA_FLAG_OVERRIDE)
385 | (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0),
386 tlladdr, (struct sockaddr *)proxydl);
390 nd6_cache_lladdr(cmpifp, &saddr6, lladdr,
391 lladdrlen, ND_NEIGHBOR_SOLICIT, 0);
393 nd6_na_output(ifp, &saddr6, &taddr6,
394 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE)
395 | (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0)
396 | ND_NA_FLAG_SOLICITED,
397 tlladdr, (struct sockaddr *)proxydl);
403 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", ip6_sprintf(&saddr6)));
404 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", ip6_sprintf(&daddr6)));
405 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", ip6_sprintf(&taddr6)));
406 icmp6stat.icp6s_badns++;
411 * Output an Neighbor Solicitation Message. Caller specifies:
412 * - ICMP6 header source IP6 address
413 * - ND6 header target IP6 address
414 * - ND6 header source datalink address
417 * Based on RFC 2462 (duplicated address detection)
420 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6,
421 const struct in6_addr *taddr6,
422 struct llinfo_nd6 *ln, /* for source address determination */
423 int dad) /* duplicated address detection */
427 struct nd_neighbor_solicit *nd_ns;
428 struct in6_ifaddr *ia = NULL;
429 struct ip6_moptions im6o;
433 struct ifnet *outif = NULL;
435 if (IN6_IS_ADDR_MULTICAST(taddr6))
438 /* estimate the size of message */
439 maxlen = sizeof(*ip6) + sizeof(*nd_ns);
440 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
441 if (max_linkhdr + maxlen >= MCLBYTES) {
443 kprintf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES "
444 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
449 m = m_getb(max_linkhdr + maxlen, M_NOWAIT, MT_DATA, M_PKTHDR);
453 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) {
454 m->m_flags |= M_MCAST;
455 im6o.im6o_multicast_ifp = ifp;
456 im6o.im6o_multicast_hlim = 255;
457 im6o.im6o_multicast_loop = 0;
460 icmp6len = sizeof(*nd_ns);
461 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len;
462 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
464 /* fill neighbor solicitation packet */
465 ip6 = mtod(m, struct ip6_hdr *);
467 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
468 ip6->ip6_vfc |= IPV6_VERSION;
469 /* ip6->ip6_plen will be set later */
470 ip6->ip6_nxt = IPPROTO_ICMPV6;
473 ip6->ip6_dst = *daddr6;
475 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
476 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index);
477 ip6->ip6_dst.s6_addr32[1] = 0;
478 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE;
479 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3];
480 ip6->ip6_dst.s6_addr8[12] = 0xff;
483 #if 0 /* KAME way, exact address scope match */
485 * Select a source whose scope is the same as that of the dest.
486 * Typically, the dest is link-local solicitation multicast
487 * (i.e. neighbor discovery) or link-local/global unicast
488 * (i.e. neighbor un-reachability detection).
490 ia = in6_ifawithifp(ifp, &ip6->ip6_dst);
495 ip6->ip6_src = ia->ia_addr.sin6_addr;
496 #else /* spec-wise correct */
499 * "If the source address of the packet prompting the
500 * solicitation is the same as one of the addresses assigned
501 * to the outgoing interface, that address SHOULD be placed
502 * in the IP Source Address of the outgoing solicitation.
503 * Otherwise, any one of the addresses assigned to the
504 * interface should be used."
506 * We use the source address for the prompting packet
508 * - saddr6 is given from the caller (by giving "ln"), and
509 * - saddr6 belongs to the outgoing interface.
510 * Otherwise, we perform a scope-wise match.
512 struct ip6_hdr *hip6; /* hold ip6 */
513 struct in6_addr *saddr6;
515 if (ln && ln->ln_hold) {
516 hip6 = mtod(ln->ln_hold, struct ip6_hdr *);
518 if (sizeof(*hip6) < ln->ln_hold->m_len)
519 saddr6 = &hip6->ip6_src;
524 if (saddr6 && in6ifa_ifpwithaddr(ifp, saddr6))
525 bcopy(saddr6, &ip6->ip6_src, sizeof(*saddr6));
527 ia = in6_ifawithifp(ifp, &ip6->ip6_dst);
532 ip6->ip6_src = ia->ia_addr.sin6_addr;
537 * Source address for DAD packet must always be IPv6
538 * unspecified address. (0::0)
540 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src));
542 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1);
543 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT;
544 nd_ns->nd_ns_code = 0;
545 nd_ns->nd_ns_reserved = 0;
546 nd_ns->nd_ns_target = *taddr6;
548 if (IN6_IS_SCOPE_LINKLOCAL(&nd_ns->nd_ns_target))
549 nd_ns->nd_ns_target.s6_addr16[1] = 0;
552 * Add source link-layer address option.
554 * spec implementation
556 * DAD packet MUST NOT do not add the option
557 * there's no link layer address:
558 * impossible do not add the option
559 * there's link layer address:
560 * Multicast NS MUST add one add the option
561 * Unicast NS SHOULD add one add the option
563 if (!dad && (mac = nd6_ifptomac(ifp))) {
564 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
565 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
566 /* 8 byte alignments... */
567 optlen = (optlen + 7) & ~7;
569 m->m_pkthdr.len += optlen;
572 bzero((caddr_t)nd_opt, optlen);
573 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR;
574 nd_opt->nd_opt_len = optlen >> 3;
575 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
578 ip6->ip6_plen = htons((u_short)icmp6len);
579 nd_ns->nd_ns_cksum = 0;
581 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len);
583 ip6_output(m, NULL, NULL, dad ? IPV6_DADOUTPUT : 0, &im6o, &outif, NULL);
585 icmp6_ifstat_inc(outif, ifs6_out_msg);
586 icmp6_ifstat_inc(outif, ifs6_out_neighborsolicit);
588 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++;
592 * Neighbor advertisement input handling.
595 * Based on RFC 2462 (duplicated address detection)
597 * the following items are not implemented yet:
598 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
599 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
602 nd6_na_input(struct mbuf *m, int off, int icmp6len)
604 struct ifnet *ifp = m->m_pkthdr.rcvif;
605 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
606 struct nd_neighbor_advert *nd_na;
607 struct in6_addr saddr6 = ip6->ip6_src;
608 struct in6_addr daddr6 = ip6->ip6_dst;
609 struct in6_addr taddr6;
617 struct llinfo_nd6 *ln;
619 struct sockaddr_dl *sdl;
620 union nd_opts ndopts;
622 if (ip6->ip6_hlim != 255) {
624 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n",
625 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src),
626 ip6_sprintf(&ip6->ip6_dst), if_name(ifp)));
630 #ifndef PULLDOWN_TEST
631 IP6_EXTHDR_CHECK(m, off, icmp6len,);
632 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off);
634 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len);
636 icmp6stat.icp6s_tooshort++;
640 taddr6 = nd_na->nd_na_target;
641 flags = nd_na->nd_na_flags_reserved;
642 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0);
643 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0);
644 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0);
646 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6))
647 taddr6.s6_addr16[1] = htons(ifp->if_index);
649 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
651 "nd6_na_input: invalid target address %s\n",
652 ip6_sprintf(&taddr6)));
655 if (IN6_IS_ADDR_MULTICAST(&daddr6))
658 "nd6_na_input: a solicited adv is multicasted\n"));
662 icmp6len -= sizeof(*nd_na);
663 nd6_option_init(nd_na + 1, icmp6len, &ndopts);
664 if (nd6_options(&ndopts) < 0) {
666 "nd6_na_input: invalid ND option, ignored\n"));
667 /* nd6_options have incremented stats */
671 if (ndopts.nd_opts_tgt_lladdr) {
672 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
673 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
676 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
679 * Target address matches one of my interface address.
681 * If my address is tentative, this means that there's somebody
682 * already using the same address as mine. This indicates DAD failure.
683 * This is defined in RFC 2462.
685 * Otherwise, process as defined in RFC 2461.
688 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) {
689 nd6_dad_na_input(ifa);
693 /* Just for safety, maybe unnecessary. */
696 "nd6_na_input: duplicate IP6 address %s\n",
697 ip6_sprintf(&taddr6));
702 * Make sure the source address is from a neighbor's address.
704 if (in6ifa_ifplocaladdr(ifp, &saddr6) == NULL) {
705 nd6log((LOG_INFO, "nd6_na_input: "
706 "NA packet from non-neighbor\n"));
710 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
712 "nd6_na_input: lladdrlen mismatch for %s "
713 "(if %d, NA packet %d)\n",
714 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2));
719 * If no neighbor cache entry is found, NA SHOULD silently be discarded.
721 rt = nd6_lookup(&taddr6, 0, ifp);
723 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) ||
724 ((sdl = SDL(rt->rt_gateway)) == NULL))
727 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
729 * If the link-layer has address, and no lladdr option came,
730 * discard the packet.
732 if (ifp->if_addrlen && !lladdr)
736 * Record link-layer address, and update the state.
738 sdl->sdl_alen = ifp->if_addrlen;
739 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
741 ln->ln_state = ND6_LLINFO_REACHABLE;
744 ln->ln_expire = time_uptime +
745 ND_IFINFO(rt->rt_ifp)->reachable;
747 ln->ln_state = ND6_LLINFO_STALE;
748 ln->ln_expire = time_uptime + nd6_gctimer;
750 if ((ln->ln_router = is_router) != 0) {
752 * This means a router's state has changed from
753 * non-reachable to probably reachable, and might
754 * affect the status of associated prefixes..
756 pfxlist_onlink_check();
762 * Check if the link-layer address has changed or not.
768 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen))
777 * This is VERY complex. Look at it with care.
779 * override solicit lladdr llchange action
784 * 0 0 y y (1) REACHABLE->STALE
785 * 0 1 n -- (2c) *->REACHABLE
786 * 0 1 y n (2b) L *->REACHABLE
787 * 0 1 y y (1) REACHABLE->STALE
790 * 1 0 y y (2a) L *->STALE
791 * 1 1 n -- (2a) *->REACHABLE
792 * 1 1 y n (2a) L *->REACHABLE
793 * 1 1 y y (2a) L *->REACHABLE
795 if (!is_override && (lladdr && llchange)) { /* (1) */
797 * If state is REACHABLE, make it STALE.
798 * no other updates should be done.
800 if (ln->ln_state == ND6_LLINFO_REACHABLE) {
801 ln->ln_state = ND6_LLINFO_STALE;
802 ln->ln_expire = time_uptime + nd6_gctimer;
805 } else if (is_override /* (2a) */
806 || (!is_override && (lladdr && !llchange)) /* (2b) */
807 || !lladdr) { /* (2c) */
809 * Update link-local address, if any.
812 sdl->sdl_alen = ifp->if_addrlen;
813 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
817 * If solicited, make the state REACHABLE.
818 * If not solicited and the link-layer address was
819 * changed, make it STALE.
822 ln->ln_state = ND6_LLINFO_REACHABLE;
825 ln->ln_expire = time_uptime +
826 ND_IFINFO(ifp)->reachable;
829 if (lladdr && llchange) {
830 ln->ln_state = ND6_LLINFO_STALE;
831 ln->ln_expire = time_uptime + nd6_gctimer;
836 if (ln->ln_router && !is_router) {
838 * The peer dropped the router flag.
839 * Remove the sender from the Default Router List and
840 * update the Destination Cache entries.
842 struct nd_defrouter *dr;
843 struct in6_addr *in6;
845 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr;
848 * Lock to protect the default router list.
849 * XXX: this might be unnecessary, since this function
850 * is only called under the network software interrupt
851 * context. However, we keep it just for safety.
854 dr = defrouter_lookup(in6, rt->rt_ifp);
857 mtx_unlock(&nd6_mtx);
859 if (dr == NULL && !ip6_forwarding && ip6_accept_rtadv) {
861 * Even if the neighbor is not in the default
862 * router list, the neighbor may be used
863 * as a next hop for some destinations
864 * (e.g. redirect case). So we must
865 * call rt6_flush explicitly.
867 rt6_flush(&ip6->ip6_src, rt->rt_ifp);
870 ln->ln_router = is_router;
872 rt->rt_flags &= ~RTF_REJECT;
876 * we assume ifp is not a loopback here, so just set the 2nd
877 * argument as the 1st one.
879 nd6_output(ifp, ifp, ln->ln_hold,
880 (struct sockaddr_in6 *)rt_key(rt), rt);
889 icmp6stat.icp6s_badna++;
894 * Neighbor advertisement output handling.
898 * the following items are not implemented yet:
899 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
900 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
903 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6,
904 const struct in6_addr *taddr6, u_long flags,
905 int tlladdr, /* 1 if include target link-layer address */
906 struct sockaddr *sdl0) /* sockaddr_dl (= proxy NA) or NULL */
910 struct nd_neighbor_advert *nd_na;
911 struct in6_ifaddr *ia = NULL;
912 struct ip6_moptions im6o;
916 struct ifnet *outif = NULL;
918 /* estimate the size of message */
919 maxlen = sizeof(*ip6) + sizeof(*nd_na);
920 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
921 if (max_linkhdr + maxlen >= MCLBYTES) {
923 kprintf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES "
924 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
929 m = m_getb(max_linkhdr + maxlen, M_NOWAIT, MT_DATA, M_PKTHDR);
933 if (IN6_IS_ADDR_MULTICAST(daddr6)) {
934 m->m_flags |= M_MCAST;
935 im6o.im6o_multicast_ifp = ifp;
936 im6o.im6o_multicast_hlim = 255;
937 im6o.im6o_multicast_loop = 0;
940 icmp6len = sizeof(*nd_na);
941 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len;
942 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
944 /* fill neighbor advertisement packet */
945 ip6 = mtod(m, struct ip6_hdr *);
947 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
948 ip6->ip6_vfc |= IPV6_VERSION;
949 ip6->ip6_nxt = IPPROTO_ICMPV6;
951 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) {
953 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
954 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index);
955 ip6->ip6_dst.s6_addr32[1] = 0;
956 ip6->ip6_dst.s6_addr32[2] = 0;
957 ip6->ip6_dst.s6_addr32[3] = IPV6_ADDR_INT32_ONE;
958 flags &= ~ND_NA_FLAG_SOLICITED;
960 ip6->ip6_dst = *daddr6;
963 * Select a source whose scope is the same as that of the dest.
965 ia = in6_ifawithifp(ifp, &ip6->ip6_dst);
970 ip6->ip6_src = ia->ia_addr.sin6_addr;
971 nd_na = (struct nd_neighbor_advert *)(ip6 + 1);
972 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT;
973 nd_na->nd_na_code = 0;
974 nd_na->nd_na_target = *taddr6;
975 if (IN6_IS_SCOPE_LINKLOCAL(&nd_na->nd_na_target))
976 nd_na->nd_na_target.s6_addr16[1] = 0;
979 * "tlladdr" indicates NS's condition for adding tlladdr or not.
980 * see nd6_ns_input() for details.
981 * Basically, if NS packet is sent to unicast/anycast addr,
982 * target lladdr option SHOULD NOT be included.
987 * sdl0 != NULL indicates proxy NA. If we do proxy, use
988 * lladdr in sdl0. If we are not proxying (sending NA for
989 * my address) use lladdr configured for the interface.
994 mac = carp_macmatch6(ifp->if_carp, m, taddr6);
996 mac = nd6_ifptomac(ifp);
998 mac = nd6_ifptomac(ifp);
1000 } else if (sdl0->sa_family == AF_LINK) {
1001 struct sockaddr_dl *sdl;
1002 sdl = (struct sockaddr_dl *)sdl0;
1003 if (sdl->sdl_alen == ifp->if_addrlen)
1008 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
1009 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1);
1011 /* roundup to 8 bytes alignment! */
1012 optlen = (optlen + 7) & ~7;
1014 m->m_pkthdr.len += optlen;
1017 bzero((caddr_t)nd_opt, optlen);
1018 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
1019 nd_opt->nd_opt_len = optlen >> 3;
1020 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
1022 flags &= ~ND_NA_FLAG_OVERRIDE;
1024 ip6->ip6_plen = htons((u_short)icmp6len);
1025 nd_na->nd_na_flags_reserved = flags;
1026 nd_na->nd_na_cksum = 0;
1027 nd_na->nd_na_cksum =
1028 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len);
1030 ip6_output(m, NULL, NULL, 0, &im6o, &outif, NULL);
1032 icmp6_ifstat_inc(outif, ifs6_out_msg);
1033 icmp6_ifstat_inc(outif, ifs6_out_neighboradvert);
1035 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++;
1039 nd6_ifptomac(struct ifnet *ifp)
1041 switch (ifp->if_type) {
1047 #ifdef IFT_IEEE80211
1053 return ((caddr_t)(ifp + 1));
1061 struct netmsg_base base;
1066 TAILQ_ENTRY(dadq) dad_list;
1067 struct ifaddr *dad_ifa;
1068 int dad_count; /* max NS to send */
1069 int dad_ns_tcount; /* # of trials to send NS */
1070 int dad_ns_ocount; /* NS sent so far */
1073 struct callout dad_timer_ch;
1074 struct netmsg_dad dad_nmsg;
1076 TAILQ_HEAD(dadq_head, dadq);
1078 static struct dadq_head dadq = TAILQ_HEAD_INITIALIZER(dadq);
1080 static struct dadq *
1081 nd6_dad_find(struct ifaddr *ifa)
1085 ASSERT_IN_NETISR(0);
1087 TAILQ_FOREACH(dp, &dadq, dad_list) {
1088 if (dp->dad_ifa == ifa)
1095 nd6_dad_starttimer(struct dadq *dp, int ticks)
1097 ASSERT_IN_NETISR(0);
1098 callout_reset(&dp->dad_timer_ch, ticks, nd6_dad_timer, dp);
1102 nd6_dad_stoptimer(struct dadq *dp)
1104 ASSERT_IN_NETISR(0);
1105 callout_stop(&dp->dad_timer_ch);
1109 * Start Duplicated Address Detection (DAD) for specified interface address.
1112 nd6_dad_start(struct ifaddr *ifa,
1113 int *tick) /* minimum delay ticks for IFF_UP event */
1115 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1118 ASSERT_IN_NETISR(0);
1121 * If we don't need DAD, don't do it.
1122 * There are several cases:
1123 * - DAD is disabled (ip6_dad_count == 0)
1124 * - the interface address is anycast
1126 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
1128 "nd6_dad_start: called with non-tentative address "
1130 ip6_sprintf(&ia->ia_addr.sin6_addr),
1131 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1134 if (ia->ia6_flags & IN6_IFF_ANYCAST) {
1135 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1138 if (!ip6_dad_count) {
1139 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1143 panic("nd6_dad_start: ifa->ifa_ifp == NULL");
1144 if (!(ifa->ifa_ifp->if_flags & IFF_UP))
1146 if (nd6_dad_find(ifa) != NULL) {
1147 /* DAD already in progress */
1151 dp = nd6_dad_create(ifa);
1152 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp),
1153 ip6_sprintf(&ia->ia_addr.sin6_addr)));
1156 * Send NS packet for DAD, dp->dad_count times.
1157 * Note that we must delay the first transmission, if this is the
1158 * first packet to be sent from the interface after interface
1159 * (re)initialization.
1162 nd6_dad_ns_output(dp);
1163 nd6_dad_starttimer(dp,
1164 ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1169 ntick = krandom() % (MAX_RTR_SOLICITATION_DELAY * hz);
1171 ntick = *tick + krandom() % (hz / 2);
1173 nd6_dad_starttimer(dp, ntick);
1178 * Terminate DAD unconditionally. Used for address removals.
1181 nd6_dad_stop(struct ifaddr *ifa)
1185 ASSERT_IN_NETISR(0);
1187 dp = nd6_dad_find(ifa);
1189 /* DAD wasn't started yet */
1192 nd6_dad_destroy(dp);
1195 static struct dadq *
1196 nd6_dad_create(struct ifaddr *ifa)
1198 struct netmsg_dad *dm;
1201 ASSERT_IN_NETISR(0);
1203 dp = kmalloc(sizeof(*dp), M_IP6NDP, M_INTWAIT | M_ZERO);
1204 callout_init_mp(&dp->dad_timer_ch);
1207 netmsg_init(&dm->base, NULL, &netisr_adone_rport,
1208 MSGF_DROPABLE | MSGF_PRIORITY, nd6_dad_timer_handler);
1212 IFAREF(ifa); /* just for safety */
1214 /* Send NS packet for DAD, ip6_dad_count times. */
1215 dp->dad_count = ip6_dad_count;
1217 TAILQ_INSERT_TAIL(&dadq, dp, dad_list);
1223 nd6_dad_destroy(struct dadq *dp)
1225 struct lwkt_msg *lmsg = &dp->dad_nmsg.base.lmsg;
1227 ASSERT_IN_NETISR(0);
1229 TAILQ_REMOVE(&dadq, dp, dad_list);
1231 nd6_dad_stoptimer(dp);
1234 if ((lmsg->ms_flags & MSGF_DONE) == 0)
1238 IFAFREE(dp->dad_ifa);
1239 kfree(dp, M_IP6NDP);
1243 nd6_dad_timer(void *xdp)
1245 struct dadq *dp = xdp;
1246 struct lwkt_msg *lmsg = &dp->dad_nmsg.base.lmsg;
1248 KASSERT(mycpuid == 0, ("dad timer not on cpu0"));
1251 if (lmsg->ms_flags & MSGF_DONE)
1252 lwkt_sendmsg_oncpu(netisr_cpuport(0), lmsg);
1257 nd6_dad_timer_handler(netmsg_t msg)
1259 struct netmsg_dad *dm = (struct netmsg_dad *)msg;
1260 struct dadq *dp = dm->dadq;
1261 struct ifaddr *ifa = dp->dad_ifa;
1262 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1264 ASSERT_IN_NETISR(0);
1268 lwkt_replymsg(&dm->base.lmsg, 0);
1271 if (ia->ia6_flags & IN6_IFF_DUPLICATED) {
1272 log(LOG_ERR, "nd6_dad_timer: called with duplicated address "
1274 ip6_sprintf(&ia->ia_addr.sin6_addr),
1275 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1278 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
1279 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address "
1281 ip6_sprintf(&ia->ia_addr.sin6_addr),
1282 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1286 /* Timed out with IFF_{RUNNING,UP} check */
1287 if (dp->dad_ns_tcount > dad_maxtry) {
1288 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n",
1289 if_name(ifa->ifa_ifp)));
1293 /* Need more checks? */
1294 if (dp->dad_ns_ocount < dp->dad_count) {
1296 * We have more NS to go. Send NS packet for DAD.
1298 nd6_dad_ns_output(dp);
1299 nd6_dad_starttimer(dp,
1300 ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1303 * We have transmitted sufficient number of DAD packets.
1304 * See what we've got.
1310 if (dp->dad_na_icount) {
1312 * the check is in nd6_dad_na_input(),
1318 if (dp->dad_ns_icount) {
1319 #if 0 /* heuristics */
1322 * - we have sent many(?) DAD NS, and
1323 * - the number of NS we sent equals to the
1324 * number of NS we've got, and
1326 * we may have a faulty network card/driver which
1327 * loops back multicasts to myself.
1329 if (3 < dp->dad_count
1330 && dp->dad_ns_icount == dp->dad_count
1331 && dp->dad_na_icount == 0) {
1332 log(LOG_INFO, "DAD questionable for %s(%s): "
1333 "network card loops back multicast?\n",
1334 ip6_sprintf(&ia->ia_addr.sin6_addr),
1335 if_name(ifa->ifa_ifp));
1336 /* XXX consider it a duplicate or not? */
1339 /* We've seen NS, means DAD has failed. */
1343 /* We've seen NS, means DAD has failed. */
1349 /* dp will be freed in nd6_dad_duplicated() */
1351 nd6_dad_duplicated(ifa);
1354 * We are done with DAD. No NA came, no NS came.
1355 * duplicated address found.
1357 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1359 "%s: DAD complete for %s - no duplicates found\n",
1360 if_name(ifa->ifa_ifp),
1361 ip6_sprintf(&ia->ia_addr.sin6_addr)));
1367 nd6_dad_destroy(dp);
1371 nd6_dad_duplicated(struct ifaddr *ifa)
1373 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1376 ASSERT_IN_NETISR(0);
1378 dp = nd6_dad_find(ifa);
1380 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n");
1385 * We are done with DAD, with duplicated address found. (failure)
1387 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: "
1388 "NS in/out=%d/%d, NA in=%d\n",
1389 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr),
1390 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount);
1392 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1393 ia->ia6_flags |= IN6_IFF_DUPLICATED;
1395 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n",
1396 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr));
1397 log(LOG_ERR, "%s: manual intervention required\n",
1398 if_name(ifa->ifa_ifp));
1400 nd6_dad_destroy(dp);
1404 nd6_dad_ns_output(struct dadq *dp)
1406 struct in6_ifaddr *ia = (struct in6_ifaddr *)dp->dad_ifa;
1407 struct ifnet *ifp = dp->dad_ifa->ifa_ifp;
1409 ASSERT_IN_NETISR(0);
1411 dp->dad_ns_tcount++;
1412 if (!(ifp->if_flags & IFF_UP)) {
1414 kprintf("%s: interface down?\n", if_name(ifp));
1418 if (!(ifp->if_flags & IFF_RUNNING)) {
1420 kprintf("%s: interface not running?\n", if_name(ifp));
1425 dp->dad_ns_ocount++;
1426 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1);
1430 nd6_dad_ns_input(struct ifaddr *ifa)
1432 struct in6_ifaddr *ia;
1433 const struct in6_addr *taddr6;
1437 ASSERT_IN_NETISR(0);
1440 panic("ifa == NULL in nd6_dad_ns_input");
1442 ia = (struct in6_ifaddr *)ifa;
1443 taddr6 = &ia->ia_addr.sin6_addr;
1445 dp = nd6_dad_find(ifa);
1447 /* Quickhack - completely ignore DAD NS packets */
1448 if (dad_ignore_ns) {
1450 "nd6_dad_ns_input: ignoring DAD NS packet for "
1451 "address %s(%s)\n", ip6_sprintf(taddr6),
1452 if_name(ifa->ifa_ifp)));
1457 * if I'm yet to start DAD, someone else started using this address
1458 * first. I have a duplicate and you win.
1460 if (!dp || dp->dad_ns_ocount == 0)
1463 /* XXX more checks for loopback situation - see nd6_dad_timer too */
1466 dp = NULL; /* will be freed in nd6_dad_duplicated() */
1467 nd6_dad_duplicated(ifa);
1470 * not sure if I got a duplicate.
1471 * increment ns count and see what happens.
1474 dp->dad_ns_icount++;
1479 nd6_dad_na_input(struct ifaddr *ifa)
1483 ASSERT_IN_NETISR(0);
1486 panic("ifa == NULL in nd6_dad_na_input");
1488 dp = nd6_dad_find(ifa);
1490 dp->dad_na_icount++;
1492 /* remove the address. */
1493 nd6_dad_duplicated(ifa);