2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the project nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * $KAME: nd6_nbr.c,v 1.86 2002/01/21 02:33:04 jinmei Exp $
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
38 #include "opt_inet6.h"
39 #include "opt_ipsec.h"
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/eventhandler.h>
44 #include <sys/malloc.h>
45 #include <sys/libkern.h>
47 #include <sys/rwlock.h>
49 #include <sys/socket.h>
50 #include <sys/sockio.h>
52 #include <sys/kernel.h>
53 #include <sys/errno.h>
54 #include <sys/sysctl.h>
55 #include <sys/syslog.h>
56 #include <sys/queue.h>
57 #include <sys/callout.h>
58 #include <sys/refcount.h>
61 #include <net/if_types.h>
62 #include <net/if_dl.h>
63 #include <net/if_var.h>
64 #include <net/route.h>
67 #include <netinet/in.h>
68 #include <netinet/in_var.h>
69 #include <net/if_llatbl.h>
70 #include <netinet6/in6_var.h>
71 #include <netinet6/in6_ifattach.h>
72 #include <netinet/ip6.h>
73 #include <netinet6/ip6_var.h>
74 #include <netinet6/scope6_var.h>
75 #include <netinet6/nd6.h>
76 #include <netinet/icmp6.h>
77 #include <netinet/ip_carp.h>
78 #include <netinet6/send.h>
80 #define SDL(s) ((struct sockaddr_dl *)s)
83 static struct dadq *nd6_dad_find(struct ifaddr *, struct nd_opt_nonce *);
84 static void nd6_dad_add(struct dadq *dp);
85 static void nd6_dad_del(struct dadq *dp);
86 static void nd6_dad_rele(struct dadq *);
87 static void nd6_dad_starttimer(struct dadq *, int);
88 static void nd6_dad_stoptimer(struct dadq *);
89 static void nd6_dad_timer(void *);
90 static void nd6_dad_duplicated(struct ifaddr *, struct dadq *);
91 static void nd6_dad_ns_output(struct dadq *);
92 static void nd6_dad_ns_input(struct ifaddr *, struct nd_opt_nonce *);
93 static void nd6_dad_na_input(struct ifaddr *);
94 static void nd6_na_output_fib(struct ifnet *, const struct in6_addr *,
95 const struct in6_addr *, u_long, int, struct sockaddr *, u_int);
96 static void nd6_ns_output_fib(struct ifnet *, const struct in6_addr *,
97 const struct in6_addr *, const struct in6_addr *, uint8_t *, u_int);
99 static struct ifaddr *nd6_proxy_fill_sdl(struct ifnet *,
100 const struct in6_addr *, struct sockaddr_dl *);
102 VNET_DEFINE_STATIC(int, dad_enhanced) = 1;
103 #define V_dad_enhanced VNET(dad_enhanced)
105 SYSCTL_DECL(_net_inet6_ip6);
106 SYSCTL_INT(_net_inet6_ip6, OID_AUTO, dad_enhanced, CTLFLAG_VNET | CTLFLAG_RW,
107 &VNET_NAME(dad_enhanced), 0,
108 "Enable Enhanced DAD, which adds a random nonce to NS messages for DAD.");
110 VNET_DEFINE_STATIC(int, dad_maxtry) = 15; /* max # of *tries* to
111 transmit DAD packet */
112 #define V_dad_maxtry VNET(dad_maxtry)
115 * Input a Neighbor Solicitation Message.
118 * Based on RFC 2462 (duplicate address detection)
121 nd6_ns_input(struct mbuf *m, int off, int icmp6len)
125 struct nd_neighbor_solicit *nd_ns;
126 struct in6_addr daddr6, myaddr6, saddr6, taddr6;
128 struct sockaddr_dl proxydl;
129 union nd_opts ndopts;
130 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
132 int anycast, lladdrlen, proxy, rflag, tentative, tlladdr;
136 /* RFC 6980: Nodes MUST silently ignore fragments */
137 if(m->m_flags & M_FRAGMENTED)
140 ifp = m->m_pkthdr.rcvif;
141 ip6 = mtod(m, struct ip6_hdr *);
142 if (__predict_false(ip6->ip6_hlim != 255)) {
143 ICMP6STAT_INC(icp6s_invlhlim);
145 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n",
146 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
147 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
151 if (m->m_len < off + icmp6len) {
152 m = m_pullup(m, off + icmp6len);
154 IP6STAT_INC(ip6s_exthdrtoolong);
158 ip6 = mtod(m, struct ip6_hdr *);
159 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off);
161 saddr6 = ip6->ip6_src;
162 daddr6 = ip6->ip6_dst;
163 taddr6 = nd_ns->nd_ns_target;
164 if (in6_setscope(&taddr6, ifp, NULL) != 0)
167 rflag = (V_ip6_forwarding) ? ND_NA_FLAG_ROUTER : 0;
168 if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV && V_ip6_norbit_raif)
171 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
172 /* dst has to be a solicited node multicast address. */
173 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL &&
174 /* don't check ifindex portion */
175 daddr6.s6_addr32[1] == 0 &&
176 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE &&
177 daddr6.s6_addr8[12] == 0xff) {
180 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
181 "(wrong ip6 dst)\n"));
184 } else if (!V_nd6_onlink_ns_rfc4861) {
185 struct sockaddr_in6 src_sa6;
188 * According to recent IETF discussions, it is not a good idea
189 * to accept a NS from an address which would not be deemed
190 * to be a neighbor otherwise. This point is expected to be
191 * clarified in future revisions of the specification.
193 bzero(&src_sa6, sizeof(src_sa6));
194 src_sa6.sin6_family = AF_INET6;
195 src_sa6.sin6_len = sizeof(src_sa6);
196 src_sa6.sin6_addr = saddr6;
197 if (nd6_is_addr_neighbor(&src_sa6, ifp) == 0) {
198 nd6log((LOG_INFO, "nd6_ns_input: "
199 "NS packet from non-neighbor\n"));
204 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
205 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n"));
209 icmp6len -= sizeof(*nd_ns);
210 nd6_option_init(nd_ns + 1, icmp6len, &ndopts);
211 if (nd6_options(&ndopts) < 0) {
213 "nd6_ns_input: invalid ND option, ignored\n"));
214 /* nd6_options have incremented stats */
220 if (ndopts.nd_opts_src_lladdr) {
221 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
222 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
225 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) {
226 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
227 "(link-layer address option)\n"));
232 * Attaching target link-layer address to the NA?
235 * NS IP dst is unicast/anycast MUST NOT add
236 * NS IP dst is solicited-node multicast MUST add
238 * In implementation, we add target link-layer address by default.
239 * We do not add one in MUST NOT cases.
241 if (!IN6_IS_ADDR_MULTICAST(&daddr6))
247 * Target address (taddr6) must be either:
248 * (1) Valid unicast/anycast address for my receiving interface,
249 * (2) Unicast address for which I'm offering proxy service, or
250 * (3) "tentative" address on which DAD is being performed.
252 /* (1) and (3) check. */
254 ifa = (*carp_iamatch6_p)(ifp, &taddr6);
256 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
261 if ((ifa = nd6_proxy_fill_sdl(ifp, &taddr6, &proxydl)) != NULL)
266 * We've got an NS packet, and we don't have that adddress
267 * assigned for us. We MUST silently ignore it.
272 myaddr6 = *IFA_IN6(ifa);
273 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST;
274 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE;
275 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED)
278 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
279 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s "
280 "(if %d, NS packet %d)\n",
281 ip6_sprintf(ip6bufs, &taddr6),
282 ifp->if_addrlen, lladdrlen - 2));
286 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) {
287 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n",
288 ip6_sprintf(ip6bufs, &saddr6)));
293 * We have neighbor solicitation packet, with target address equals to
294 * one of my tentative address.
296 * src addr how to process?
298 * multicast of course, invalid (rejected in ip6_input)
299 * unicast somebody is doing address resolution -> ignore
300 * unspec dup address detection
302 * The processing is defined in RFC 2462.
306 * If source address is unspecified address, it is for
307 * duplicate address detection.
309 * If not, the packet is for addess resolution;
310 * silently ignore it.
312 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6))
313 nd6_dad_ns_input(ifa, ndopts.nd_opts_nonce);
319 * If the source address is unspecified address, entries must not
320 * be created or updated.
321 * It looks that sender is performing DAD. Output NA toward
322 * all-node multicast address, to tell the sender that I'm using
324 * S bit ("solicited") must be zero.
326 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
327 struct in6_addr in6_all;
329 in6_all = in6addr_linklocal_allnodes;
330 if (in6_setscope(&in6_all, ifp, NULL) != 0)
332 nd6_na_output_fib(ifp, &in6_all, &taddr6,
333 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
334 rflag, tlladdr, proxy ? (struct sockaddr *)&proxydl : NULL,
339 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen,
340 ND_NEIGHBOR_SOLICIT, 0);
342 nd6_na_output_fib(ifp, &saddr6, &taddr6,
343 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
344 rflag | ND_NA_FLAG_SOLICITED, tlladdr,
345 proxy ? (struct sockaddr *)&proxydl : NULL, M_GETFIB(m));
353 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n",
354 ip6_sprintf(ip6bufs, &saddr6)));
355 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n",
356 ip6_sprintf(ip6bufs, &daddr6)));
357 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n",
358 ip6_sprintf(ip6bufs, &taddr6)));
360 ICMP6STAT_INC(icp6s_badns);
366 static struct ifaddr *
367 nd6_proxy_fill_sdl(struct ifnet *ifp, const struct in6_addr *taddr6,
368 struct sockaddr_dl *sdl)
374 ln = nd6_lookup(taddr6, LLE_SF(AF_INET6, 0), ifp);
377 if ((ln->la_flags & (LLE_PUB | LLE_VALID)) == (LLE_PUB | LLE_VALID)) {
378 link_init_sdl(ifp, (struct sockaddr *)sdl, ifp->if_type);
379 sdl->sdl_alen = ifp->if_addrlen;
380 bcopy(ln->ll_addr, &sdl->sdl_data, ifp->if_addrlen);
382 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp,
383 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
391 * Output a Neighbor Solicitation Message. Caller specifies:
392 * - ICMP6 header source IP6 address
393 * - ND6 header target IP6 address
394 * - ND6 header source datalink address
397 * Based on RFC 2462 (duplicate address detection)
399 * ln - for source address determination
400 * nonce - If non-NULL, NS is used for duplicate address detection and
401 * the value (length is ND_OPT_NONCE_LEN) is used as a random nonce.
404 nd6_ns_output_fib(struct ifnet *ifp, const struct in6_addr *saddr6,
405 const struct in6_addr *daddr6, const struct in6_addr *taddr6,
406 uint8_t *nonce, u_int fibnum)
411 struct nd_neighbor_solicit *nd_ns;
412 struct ip6_moptions im6o;
418 if (IN6_IS_ADDR_MULTICAST(taddr6))
421 /* estimate the size of message */
422 maxlen = sizeof(*ip6) + sizeof(*nd_ns);
423 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
424 KASSERT(max_linkhdr + maxlen <= MCLBYTES, (
425 "%s: max_linkhdr + maxlen > MCLBYTES (%d + %d > %d)",
426 __func__, max_linkhdr, maxlen, MCLBYTES));
428 if (max_linkhdr + maxlen > MHLEN)
429 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
431 m = m_gethdr(M_NOWAIT, MT_DATA);
436 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) {
437 m->m_flags |= M_MCAST;
438 im6o.im6o_multicast_ifp = ifp;
439 im6o.im6o_multicast_hlim = 255;
440 im6o.im6o_multicast_loop = 0;
443 icmp6len = sizeof(*nd_ns);
444 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len;
445 m->m_data += max_linkhdr; /* or M_ALIGN() equivalent? */
447 /* fill neighbor solicitation packet */
448 ip6 = mtod(m, struct ip6_hdr *);
450 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
451 ip6->ip6_vfc |= IPV6_VERSION;
452 /* ip6->ip6_plen will be set later */
453 ip6->ip6_nxt = IPPROTO_ICMPV6;
456 ip6->ip6_dst = *daddr6;
458 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
459 ip6->ip6_dst.s6_addr16[1] = 0;
460 ip6->ip6_dst.s6_addr32[1] = 0;
461 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE;
462 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3];
463 ip6->ip6_dst.s6_addr8[12] = 0xff;
464 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0)
468 char ip6buf[INET6_ADDRSTRLEN];
469 struct ifaddr *ifa = NULL;
473 * "If the source address of the packet prompting the
474 * solicitation is the same as one of the addresses assigned
475 * to the outgoing interface, that address SHOULD be placed
476 * in the IP Source Address of the outgoing solicitation.
477 * Otherwise, any one of the addresses assigned to the
478 * interface should be used."
480 * We use the source address for the prompting packet
481 * (saddr6), if saddr6 belongs to the outgoing interface.
482 * Otherwise, we perform the source address selection as usual.
485 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, saddr6);
488 struct in6_addr dst6, src6;
491 in6_splitscope(&ip6->ip6_dst, &dst6, &scopeid);
492 error = in6_selectsrc_addr(fibnum, &dst6,
493 scopeid, ifp, &src6, NULL);
495 nd6log((LOG_DEBUG, "%s: source can't be "
496 "determined: dst=%s, error=%d\n", __func__,
497 ip6_sprintf(ip6buf, &dst6),
503 ip6->ip6_src = *saddr6;
505 if (ifp->if_carp != NULL) {
507 * Check that selected source address belongs to
511 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp,
514 * Do not send NS for CARP address if we are not
517 if (ifa != NULL && ifa->ifa_carp != NULL &&
518 !(*carp_master_p)(ifa)) {
520 "nd6_ns_output: NS from BACKUP CARP address %s\n",
521 ip6_sprintf(ip6buf, &ip6->ip6_src));
530 * Source address for DAD packet must always be IPv6
531 * unspecified address. (0::0)
532 * We actually don't have to 0-clear the address (we did it
533 * above), but we do so here explicitly to make the intention
536 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src));
538 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1);
539 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT;
540 nd_ns->nd_ns_code = 0;
541 nd_ns->nd_ns_reserved = 0;
542 nd_ns->nd_ns_target = *taddr6;
543 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */
546 * Add source link-layer address option.
548 * spec implementation
550 * DAD packet MUST NOT do not add the option
551 * there's no link layer address:
552 * impossible do not add the option
553 * there's link layer address:
554 * Multicast NS MUST add one add the option
555 * Unicast NS SHOULD add one add the option
558 struct nd_opt_hdr *nd_opt;
564 mac = (*carp_macmatch6_p)(ifp, m, &ip6->ip6_src);
566 mac = nd6_ifptomac(ifp);
569 nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
570 optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
571 /* 8 byte alignments... */
572 optlen = (optlen + 7) & ~7;
573 m->m_pkthdr.len += optlen;
576 bzero(nd_opt, optlen);
577 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR;
578 nd_opt->nd_opt_len = optlen >> 3;
579 bcopy(mac, nd_opt + 1, ifp->if_addrlen);
583 * Add a Nonce option (RFC 3971) to detect looped back NS messages.
584 * This behavior is documented as Enhanced Duplicate Address
585 * Detection in RFC 7527.
586 * net.inet6.ip6.dad_enhanced=0 disables this.
588 if (V_dad_enhanced != 0 && nonce != NULL) {
589 int optlen = sizeof(struct nd_opt_hdr) + ND_OPT_NONCE_LEN;
590 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
591 /* 8-byte alignment is required. */
592 optlen = (optlen + 7) & ~7;
594 m->m_pkthdr.len += optlen;
597 bzero((caddr_t)nd_opt, optlen);
598 nd_opt->nd_opt_type = ND_OPT_NONCE;
599 nd_opt->nd_opt_len = optlen >> 3;
600 bcopy(nonce, (caddr_t)(nd_opt + 1), ND_OPT_NONCE_LEN);
602 ip6->ip6_plen = htons((u_short)icmp6len);
603 nd_ns->nd_ns_cksum = 0;
605 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len);
607 if (send_sendso_input_hook != NULL) {
608 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING,
609 sizeof(unsigned short), M_NOWAIT);
612 *(unsigned short *)(mtag + 1) = nd_ns->nd_ns_type;
613 m_tag_prepend(m, mtag);
616 ip6_output(m, NULL, NULL, (nonce != NULL) ? IPV6_UNSPECSRC : 0,
618 icmp6_ifstat_inc(ifp, ifs6_out_msg);
619 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit);
620 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_SOLICIT]);
630 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *saddr6,
631 const struct in6_addr *daddr6, const struct in6_addr *taddr6,uint8_t *nonce)
634 nd6_ns_output_fib(ifp, saddr6, daddr6, taddr6, nonce, RT_DEFAULT_FIB);
638 * Neighbor advertisement input handling.
641 * Based on RFC 2462 (duplicate address detection)
643 * the following items are not implemented yet:
644 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
645 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
648 nd6_na_input(struct mbuf *m, int off, int icmp6len)
655 struct nd_neighbor_advert *nd_na;
656 struct in6_addr daddr6, taddr6;
657 union nd_opts ndopts;
658 u_char linkhdr[LLE_MAX_LINKHDR];
659 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
662 int flags, is_override, is_router, is_solicited;
663 int lladdr_off, lladdrlen, checklink;
664 bool flush_holdchain = false;
672 /* RFC 6980: Nodes MUST silently ignore fragments */
673 if(m->m_flags & M_FRAGMENTED)
676 ifp = m->m_pkthdr.rcvif;
677 ip6 = mtod(m, struct ip6_hdr *);
678 if (__predict_false(ip6->ip6_hlim != 255)) {
679 ICMP6STAT_INC(icp6s_invlhlim);
681 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n",
682 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
683 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
687 if (m->m_len < off + icmp6len) {
688 m = m_pullup(m, off + icmp6len);
690 IP6STAT_INC(ip6s_exthdrtoolong);
694 ip6 = mtod(m, struct ip6_hdr *);
695 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off);
697 flags = nd_na->nd_na_flags_reserved;
698 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0);
699 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0);
700 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0);
702 taddr6 = nd_na->nd_na_target;
703 if (in6_setscope(&taddr6, ifp, NULL))
704 goto bad; /* XXX: impossible */
706 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
708 "nd6_na_input: invalid target address %s\n",
709 ip6_sprintf(ip6bufs, &taddr6)));
713 daddr6 = ip6->ip6_dst;
714 if (IN6_IS_ADDR_MULTICAST(&daddr6))
717 "nd6_na_input: a solicited adv is multicasted\n"));
721 icmp6len -= sizeof(*nd_na);
722 nd6_option_init(nd_na + 1, icmp6len, &ndopts);
723 if (nd6_options(&ndopts) < 0) {
725 "nd6_na_input: invalid ND option, ignored\n"));
726 /* nd6_options have incremented stats */
732 if (ndopts.nd_opts_tgt_lladdr) {
733 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
734 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
737 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
738 if (ifa != NULL && ifa->ifa_carp != NULL) {
740 * Silently ignore NAs for CARP addresses if we are not
743 if (!(*carp_master_p)(ifa)) {
745 "nd6_na_input: NA for BACKUP CARP address %s\n",
746 ip6_sprintf(ip6bufs, &taddr6));
752 * Target address matches one of my interface address.
754 * If my address is tentative, this means that there's somebody
755 * already using the same address as mine. This indicates DAD failure.
756 * This is defined in RFC 2462.
758 * Otherwise, process as defined in RFC 2461.
761 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) {
762 nd6_dad_na_input(ifa);
767 /* Just for safety, maybe unnecessary. */
771 "nd6_na_input: duplicate IP6 address %s\n",
772 ip6_sprintf(ip6bufs, &taddr6));
776 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
777 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s "
778 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6),
779 ifp->if_addrlen, lladdrlen - 2));
784 * If no neighbor cache entry is found, NA SHOULD silently be
787 ln = nd6_lookup(&taddr6, LLE_SF(AF_INET6, LLE_EXCLUSIVE), ifp);
793 * Do not try to override static entry.
795 if (ln->la_flags & LLE_STATIC)
798 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
800 * If the link-layer has address, and no lladdr option came,
801 * discard the packet.
803 if (ifp->if_addrlen && lladdr == NULL) {
808 * Record link-layer address, and update the state.
810 if (!nd6_try_set_entry_addr(ifp, ln, lladdr))
813 flush_holdchain = true;
815 nd6_llinfo_setstate(ln, ND6_LLINFO_REACHABLE);
817 nd6_llinfo_setstate(ln, ND6_LLINFO_STALE);
818 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED);
819 if ((ln->ln_router = is_router) != 0) {
821 * This means a router's state has changed from
822 * non-reachable to probably reachable, and might
823 * affect the status of associated prefixes..
831 * Check if the link-layer address has changed or not.
836 if (ln->la_flags & LLE_VALID) {
837 if (bcmp(lladdr, ln->ll_addr, ifp->if_addrlen))
846 * This is VERY complex. Look at it with care.
848 * override solicit lladdr llchange action
853 * 0 0 y y (1) REACHABLE->STALE
854 * 0 1 n -- (2c) *->REACHABLE
855 * 0 1 y n (2b) L *->REACHABLE
856 * 0 1 y y (1) REACHABLE->STALE
859 * 1 0 y y (2a) L *->STALE
860 * 1 1 n -- (2a) *->REACHABLE
861 * 1 1 y n (2a) L *->REACHABLE
862 * 1 1 y y (2a) L *->REACHABLE
864 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */
866 * If state is REACHABLE, make it STALE.
867 * no other updates should be done.
869 if (ln->ln_state == ND6_LLINFO_REACHABLE)
870 nd6_llinfo_setstate(ln, ND6_LLINFO_STALE);
872 } else if (is_override /* (2a) */
873 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */
874 || lladdr == NULL) { /* (2c) */
876 * Update link-local address, if any.
878 if (lladdr != NULL) {
879 linkhdrsize = sizeof(linkhdr);
880 if (lltable_calc_llheader(ifp, AF_INET6, lladdr,
881 linkhdr, &linkhdrsize, &lladdr_off) != 0)
883 if (lltable_try_set_entry_addr(ifp, ln, linkhdr,
884 linkhdrsize, lladdr_off) == 0)
886 EVENTHANDLER_INVOKE(lle_event, ln,
891 * If solicited, make the state REACHABLE.
892 * If not solicited and the link-layer address was
893 * changed, make it STALE.
896 nd6_llinfo_setstate(ln, ND6_LLINFO_REACHABLE);
898 if (lladdr != NULL && llchange)
899 nd6_llinfo_setstate(ln, ND6_LLINFO_STALE);
903 if (ln->ln_router && !is_router) {
905 * The peer dropped the router flag.
906 * Remove the sender from the Default Router List and
907 * update the Destination Cache entries.
909 struct ifnet *nd6_ifp;
911 nd6_ifp = lltable_get_ifp(ln->lle_tbl);
912 if (!defrouter_remove(&ln->r_l3addr.addr6, nd6_ifp) &&
913 (ND_IFINFO(nd6_ifp)->flags &
914 ND6_IFF_ACCEPT_RTADV) != 0)
916 * Even if the neighbor is not in the default
917 * router list, the neighbor may be used as a
918 * next hop for some destinations (e.g. redirect
919 * case). So we must call rt6_flush explicitly.
921 rt6_flush(&ip6->ip6_src, ifp);
923 ln->ln_router = is_router;
927 * rt->rt_flags &= ~RTF_REJECT;
930 if (ln->la_hold != NULL)
931 chain = nd6_grab_holdchain(ln);
937 nd6_flush_holdchain(ifp, ln, chain);
939 nd6_flush_children_holdchain(ifp, ln);
942 pfxlist_onlink_check();
951 ICMP6STAT_INC(icp6s_badna);
956 * Neighbor advertisement output handling.
960 * the following items are not implemented yet:
961 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
962 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
964 * tlladdr - 1 if include target link-layer address
965 * sdl0 - sockaddr_dl (= proxy NA) or NULL
968 nd6_na_output_fib(struct ifnet *ifp, const struct in6_addr *daddr6_0,
969 const struct in6_addr *taddr6, u_long flags, int tlladdr,
970 struct sockaddr *sdl0, u_int fibnum)
975 struct nd_neighbor_advert *nd_na;
976 struct ip6_moptions im6o;
977 struct in6_addr daddr6, dst6, src6;
982 int icmp6len, maxlen, error;
985 daddr6 = *daddr6_0; /* make a local copy for modification */
987 /* estimate the size of message */
988 maxlen = sizeof(*ip6) + sizeof(*nd_na);
989 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
990 KASSERT(max_linkhdr + maxlen <= MCLBYTES, (
991 "%s: max_linkhdr + maxlen > MCLBYTES (%d + %d > %d)",
992 __func__, max_linkhdr, maxlen, MCLBYTES));
994 if (max_linkhdr + maxlen > MHLEN)
995 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
997 m = m_gethdr(M_NOWAIT, MT_DATA);
1000 M_SETFIB(m, fibnum);
1002 if (IN6_IS_ADDR_MULTICAST(&daddr6)) {
1003 m->m_flags |= M_MCAST;
1004 im6o.im6o_multicast_ifp = ifp;
1005 im6o.im6o_multicast_hlim = 255;
1006 im6o.im6o_multicast_loop = 0;
1009 icmp6len = sizeof(*nd_na);
1010 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len;
1011 m->m_data += max_linkhdr; /* or M_ALIGN() equivalent? */
1013 /* fill neighbor advertisement packet */
1014 ip6 = mtod(m, struct ip6_hdr *);
1016 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
1017 ip6->ip6_vfc |= IPV6_VERSION;
1018 ip6->ip6_nxt = IPPROTO_ICMPV6;
1019 ip6->ip6_hlim = 255;
1020 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) {
1022 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
1023 daddr6.s6_addr16[1] = 0;
1024 daddr6.s6_addr32[1] = 0;
1025 daddr6.s6_addr32[2] = 0;
1026 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE;
1027 if (in6_setscope(&daddr6, ifp, NULL))
1030 flags &= ~ND_NA_FLAG_SOLICITED;
1032 ip6->ip6_dst = daddr6;
1035 * Select a source whose scope is the same as that of the dest.
1037 in6_splitscope(&daddr6, &dst6, &scopeid);
1038 error = in6_selectsrc_addr(fibnum, &dst6,
1039 scopeid, ifp, &src6, NULL);
1041 char ip6buf[INET6_ADDRSTRLEN];
1042 nd6log((LOG_DEBUG, "nd6_na_output: source can't be "
1043 "determined: dst=%s, error=%d\n",
1044 ip6_sprintf(ip6buf, &daddr6), error));
1047 ip6->ip6_src = src6;
1048 nd_na = (struct nd_neighbor_advert *)(ip6 + 1);
1049 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT;
1050 nd_na->nd_na_code = 0;
1051 nd_na->nd_na_target = *taddr6;
1052 in6_clearscope(&nd_na->nd_na_target); /* XXX */
1055 * "tlladdr" indicates NS's condition for adding tlladdr or not.
1056 * see nd6_ns_input() for details.
1057 * Basically, if NS packet is sent to unicast/anycast addr,
1058 * target lladdr option SHOULD NOT be included.
1062 * sdl0 != NULL indicates proxy NA. If we do proxy, use
1063 * lladdr in sdl0. If we are not proxying (sending NA for
1064 * my address) use lladdr configured for the interface.
1068 mac = (*carp_macmatch6_p)(ifp, m, taddr6);
1070 mac = nd6_ifptomac(ifp);
1071 } else if (sdl0->sa_family == AF_LINK) {
1072 struct sockaddr_dl *sdl;
1073 sdl = (struct sockaddr_dl *)sdl0;
1074 if (sdl->sdl_alen == ifp->if_addrlen)
1078 if (tlladdr && mac) {
1079 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
1080 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1);
1082 /* roundup to 8 bytes alignment! */
1083 optlen = (optlen + 7) & ~7;
1085 m->m_pkthdr.len += optlen;
1088 bzero((caddr_t)nd_opt, optlen);
1089 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
1090 nd_opt->nd_opt_len = optlen >> 3;
1091 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
1093 flags &= ~ND_NA_FLAG_OVERRIDE;
1095 ip6->ip6_plen = htons((u_short)icmp6len);
1096 nd_na->nd_na_flags_reserved = flags;
1097 nd_na->nd_na_cksum = 0;
1098 nd_na->nd_na_cksum =
1099 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len);
1101 if (send_sendso_input_hook != NULL) {
1102 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING,
1103 sizeof(unsigned short), M_NOWAIT);
1106 *(unsigned short *)(mtag + 1) = nd_na->nd_na_type;
1107 m_tag_prepend(m, mtag);
1110 ip6_output(m, NULL, NULL, 0, &im6o, NULL, NULL);
1111 icmp6_ifstat_inc(ifp, ifs6_out_msg);
1112 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert);
1113 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]);
1121 #ifndef BURN_BRIDGES
1123 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0,
1124 const struct in6_addr *taddr6, u_long flags, int tlladdr,
1125 struct sockaddr *sdl0)
1128 nd6_na_output_fib(ifp, daddr6_0, taddr6, flags, tlladdr, sdl0,
1134 nd6_ifptomac(struct ifnet *ifp)
1136 switch (ifp->if_type) {
1140 case IFT_INFINIBAND:
1142 return IF_LLADDR(ifp);
1149 TAILQ_ENTRY(dadq) dad_list;
1150 struct ifaddr *dad_ifa;
1151 int dad_count; /* max NS to send */
1152 int dad_ns_tcount; /* # of trials to send NS */
1153 int dad_ns_ocount; /* NS sent so far */
1156 int dad_ns_lcount; /* looped back NS */
1157 int dad_loopbackprobe; /* probing state for loopback detection */
1158 struct callout dad_timer_ch;
1159 struct vnet *dad_vnet;
1161 #define ND_OPT_NONCE_LEN32 \
1162 ((ND_OPT_NONCE_LEN + sizeof(uint32_t) - 1)/sizeof(uint32_t))
1163 uint32_t dad_nonce[ND_OPT_NONCE_LEN32];
1164 bool dad_ondadq; /* on dadq? Protected by DADQ_WLOCK. */
1167 VNET_DEFINE_STATIC(TAILQ_HEAD(, dadq), dadq);
1168 VNET_DEFINE_STATIC(struct rwlock, dad_rwlock);
1169 #define V_dadq VNET(dadq)
1170 #define V_dad_rwlock VNET(dad_rwlock)
1172 #define DADQ_LOCKPTR() (&V_dad_rwlock)
1173 #define DADQ_LOCK_INIT() rw_init(DADQ_LOCKPTR(), "nd6 DAD queue")
1174 #define DADQ_RLOCK() rw_rlock(DADQ_LOCKPTR())
1175 #define DADQ_RUNLOCK() rw_runlock(DADQ_LOCKPTR())
1176 #define DADQ_WLOCK() rw_wlock(DADQ_LOCKPTR())
1177 #define DADQ_WUNLOCK() rw_wunlock(DADQ_LOCKPTR())
1179 #define DADQ_LOCK_ASSERT() rw_assert(DADQ_LOCKPTR(), RA_LOCKED);
1180 #define DADQ_RLOCK_ASSERT() rw_assert(DADQ_LOCKPTR(), RA_RLOCKED);
1181 #define DADQ_WLOCK_ASSERT() rw_assert(DADQ_LOCKPTR(), RA_WLOCKED);
1184 nd6_dad_add(struct dadq *dp)
1186 DADQ_WLOCK_ASSERT();
1188 TAILQ_INSERT_TAIL(&V_dadq, dp, dad_list);
1189 dp->dad_ondadq = true;
1193 nd6_dad_del(struct dadq *dp)
1195 DADQ_WLOCK_ASSERT();
1197 if (dp->dad_ondadq) {
1199 * Remove dp from the dadq and release the dadq's
1202 TAILQ_REMOVE(&V_dadq, dp, dad_list);
1203 dp->dad_ondadq = false;
1208 static struct dadq *
1209 nd6_dad_find(struct ifaddr *ifa, struct nd_opt_nonce *n)
1215 TAILQ_FOREACH(dp, &V_dadq, dad_list) {
1216 if (dp->dad_ifa != ifa)
1220 * Skip if the nonce matches the received one.
1221 * +2 in the length is required because of type and
1222 * length fields are included in a header.
1225 n->nd_opt_nonce_len == (ND_OPT_NONCE_LEN + 2) / 8 &&
1226 memcmp(&n->nd_opt_nonce[0], &dp->dad_nonce[0],
1227 ND_OPT_NONCE_LEN) == 0) {
1228 dp->dad_ns_lcount++;
1238 nd6_dad_starttimer(struct dadq *dp, int ticks)
1240 DADQ_WLOCK_ASSERT();
1242 callout_reset(&dp->dad_timer_ch, ticks, nd6_dad_timer, dp);
1246 nd6_dad_stoptimer(struct dadq *dp)
1248 callout_drain(&dp->dad_timer_ch);
1252 nd6_dad_rele(struct dadq *dp)
1254 if (refcount_release(&dp->dad_refcnt)) {
1255 KASSERT(!dp->dad_ondadq, ("dp %p still on DAD queue", dp));
1256 ifa_free(dp->dad_ifa);
1265 TAILQ_INIT(&V_dadq);
1269 * Start Duplicate Address Detection (DAD) for specified interface address.
1272 nd6_dad_start(struct ifaddr *ifa, int delay)
1274 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1276 char ip6buf[INET6_ADDRSTRLEN];
1278 KASSERT((ia->ia6_flags & IN6_IFF_TENTATIVE) != 0,
1279 ("starting DAD on non-tentative address %p", ifa));
1282 * If we don't need DAD, don't do it.
1283 * There are several cases:
1284 * - DAD is disabled globally or on the interface
1285 * - the interface address is anycast
1287 if ((ia->ia6_flags & IN6_IFF_ANYCAST) != 0 ||
1288 V_ip6_dad_count == 0 ||
1289 (ND_IFINFO(ifa->ifa_ifp)->flags & ND6_IFF_NO_DAD) != 0) {
1290 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1293 if ((ifa->ifa_ifp->if_flags & IFF_UP) == 0 ||
1294 (ifa->ifa_ifp->if_drv_flags & IFF_DRV_RUNNING) == 0 ||
1295 (ND_IFINFO(ifa->ifa_ifp)->flags & ND6_IFF_IFDISABLED) != 0)
1299 if ((dp = nd6_dad_find(ifa, NULL)) != NULL) {
1301 * DAD is already in progress. Let the existing entry
1308 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT | M_ZERO);
1310 log(LOG_ERR, "nd6_dad_start: memory allocation failed for "
1312 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1313 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1316 callout_init_rw(&dp->dad_timer_ch, DADQ_LOCKPTR(),
1317 CALLOUT_RETURNUNLOCKED);
1319 dp->dad_vnet = curvnet;
1321 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp),
1322 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1325 * Send NS packet for DAD, ip6_dad_count times.
1326 * Note that we must delay the first transmission, if this is the
1327 * first packet to be sent from the interface after interface
1328 * (re)initialization.
1331 ifa_ref(dp->dad_ifa);
1332 dp->dad_count = V_ip6_dad_count;
1333 dp->dad_ns_icount = dp->dad_na_icount = 0;
1334 dp->dad_ns_ocount = dp->dad_ns_tcount = 0;
1335 dp->dad_ns_lcount = dp->dad_loopbackprobe = 0;
1337 /* Add this to the dadq and add a reference for the dadq. */
1338 refcount_init(&dp->dad_refcnt, 1);
1340 nd6_dad_starttimer(dp, delay);
1345 * terminate DAD unconditionally. used for address removals.
1348 nd6_dad_stop(struct ifaddr *ifa)
1353 dp = nd6_dad_find(ifa, NULL);
1356 /* DAD wasn't started yet */
1361 * Acquire a temporary reference so that we can safely stop the callout.
1363 (void)refcount_acquire(&dp->dad_refcnt);
1367 nd6_dad_stoptimer(dp);
1372 nd6_dad_timer(void *arg)
1374 struct dadq *dp = arg;
1375 struct ifaddr *ifa = dp->dad_ifa;
1376 struct ifnet *ifp = dp->dad_ifa->ifa_ifp;
1377 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1378 char ip6buf[INET6_ADDRSTRLEN];
1379 struct epoch_tracker et;
1381 CURVNET_SET(dp->dad_vnet);
1382 KASSERT(ia != NULL, ("DAD entry %p with no address", dp));
1384 NET_EPOCH_ENTER(et);
1385 if (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) {
1386 /* Do not need DAD for ifdisabled interface. */
1387 log(LOG_ERR, "nd6_dad_timer: cancel DAD on %s because of "
1388 "ND6_IFF_IFDISABLED.\n", ifp->if_xname);
1391 if (ia->ia6_flags & IN6_IFF_DUPLICATED) {
1392 log(LOG_ERR, "nd6_dad_timer: called with duplicated address "
1394 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1395 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1398 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) {
1399 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address "
1401 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1402 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1406 /* Stop DAD if the interface is down even after dad_maxtry attempts. */
1407 if ((dp->dad_ns_tcount > V_dad_maxtry) &&
1408 (((ifp->if_flags & IFF_UP) == 0) ||
1409 ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0))) {
1410 nd6log((LOG_INFO, "%s: could not run DAD "
1411 "because the interface was down or not running.\n",
1412 if_name(ifa->ifa_ifp)));
1416 /* Need more checks? */
1417 if (dp->dad_ns_ocount < dp->dad_count) {
1419 * We have more NS to go. Send NS packet for DAD.
1421 nd6_dad_starttimer(dp,
1422 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1423 nd6_dad_ns_output(dp);
1427 * We have transmitted sufficient number of DAD packets.
1428 * See what we've got.
1430 if (dp->dad_ns_icount > 0 || dp->dad_na_icount > 0) {
1431 /* We've seen NS or NA, means DAD has failed. */
1432 nd6_dad_duplicated(ifa, dp);
1433 } else if (V_dad_enhanced != 0 &&
1434 dp->dad_ns_lcount > 0 &&
1435 dp->dad_ns_lcount > dp->dad_loopbackprobe) {
1437 * Sec. 4.1 in RFC 7527 requires transmission of
1438 * additional probes until the loopback condition
1439 * becomes clear when a looped back probe is detected.
1441 log(LOG_ERR, "%s: a looped back NS message is "
1442 "detected during DAD for %s. "
1443 "Another DAD probes are being sent.\n",
1444 if_name(ifa->ifa_ifp),
1445 ip6_sprintf(ip6buf, IFA_IN6(ifa)));
1446 dp->dad_loopbackprobe = dp->dad_ns_lcount;
1448 * Send an NS immediately and increase dad_count by
1449 * V_nd6_mmaxtries - 1.
1452 dp->dad_ns_ocount + V_nd6_mmaxtries - 1;
1453 nd6_dad_starttimer(dp,
1454 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1455 nd6_dad_ns_output(dp);
1459 * We are done with DAD. No NA came, no NS came.
1460 * No duplicate address found. Check IFDISABLED flag
1461 * again in case that it is changed between the
1462 * beginning of this function and here.
1464 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) == 0)
1465 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1468 "%s: DAD complete for %s - no duplicates found\n",
1469 if_name(ifa->ifa_ifp),
1470 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1471 if (dp->dad_ns_lcount > 0)
1472 log(LOG_ERR, "%s: DAD completed while "
1473 "a looped back NS message is detected "
1474 "during DAD for %s.\n",
1475 if_name(ifa->ifa_ifp),
1476 ip6_sprintf(ip6buf, IFA_IN6(ifa)));
1488 nd6_dad_duplicated(struct ifaddr *ifa, struct dadq *dp)
1490 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1492 char ip6buf[INET6_ADDRSTRLEN];
1494 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: "
1495 "NS in/out/loopback=%d/%d/%d, NA in=%d\n",
1496 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1497 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_ns_lcount,
1500 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1501 ia->ia6_flags |= IN6_IFF_DUPLICATED;
1504 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n",
1505 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr));
1506 log(LOG_ERR, "%s: manual intervention required\n",
1510 * If the address is a link-local address formed from an interface
1511 * identifier based on the hardware address which is supposed to be
1512 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP
1513 * operation on the interface SHOULD be disabled.
1514 * [RFC 4862, Section 5.4.5]
1516 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) {
1517 struct in6_addr in6;
1520 * To avoid over-reaction, we only apply this logic when we are
1521 * very sure that hardware addresses are supposed to be unique.
1523 switch (ifp->if_type) {
1527 case IFT_INFINIBAND:
1528 in6 = ia->ia_addr.sin6_addr;
1529 if (in6_get_hw_ifid(ifp, &in6) == 0 &&
1530 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) {
1531 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED;
1532 log(LOG_ERR, "%s: possible hardware address "
1533 "duplication detected, disable IPv6\n",
1542 * Transmit a neighbour solicitation for the purpose of DAD. Returns with the
1543 * DAD queue unlocked.
1546 nd6_dad_ns_output(struct dadq *dp)
1548 struct in6_ifaddr *ia = (struct in6_ifaddr *)dp->dad_ifa;
1549 struct ifnet *ifp = dp->dad_ifa->ifa_ifp;
1552 DADQ_WLOCK_ASSERT();
1554 dp->dad_ns_tcount++;
1555 if ((ifp->if_flags & IFF_UP) == 0) {
1559 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
1564 dp->dad_ns_ocount++;
1565 if (V_dad_enhanced != 0) {
1566 for (i = 0; i < ND_OPT_NONCE_LEN32; i++)
1567 dp->dad_nonce[i] = arc4random();
1569 * XXXHRS: Note that in the case that
1570 * DupAddrDetectTransmits > 1, multiple NS messages with
1571 * different nonces can be looped back in an unexpected
1572 * order. The current implementation recognizes only
1573 * the latest nonce on the sender side. Practically it
1574 * should work well in almost all cases.
1578 nd6_ns_output(ifp, NULL, NULL, &ia->ia_addr.sin6_addr,
1579 (uint8_t *)&dp->dad_nonce[0]);
1583 nd6_dad_ns_input(struct ifaddr *ifa, struct nd_opt_nonce *ndopt_nonce)
1588 panic("ifa == NULL in nd6_dad_ns_input");
1590 /* Ignore Nonce option when Enhanced DAD is disabled. */
1591 if (V_dad_enhanced == 0)
1594 dp = nd6_dad_find(ifa, ndopt_nonce);
1596 dp->dad_ns_icount++;
1601 nd6_dad_na_input(struct ifaddr *ifa)
1606 panic("ifa == NULL in nd6_dad_na_input");
1609 dp = nd6_dad_find(ifa, NULL);
1611 dp->dad_na_icount++;