2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the project nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * $KAME: nd6_nbr.c,v 1.86 2002/01/21 02:33:04 jinmei Exp $
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
36 #include "opt_inet6.h"
37 #include "opt_ipsec.h"
38 #include "opt_mpath.h"
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/malloc.h>
43 #include <sys/libkern.h>
45 #include <sys/rwlock.h>
47 #include <sys/socket.h>
48 #include <sys/sockio.h>
50 #include <sys/kernel.h>
51 #include <sys/errno.h>
52 #include <sys/sysctl.h>
53 #include <sys/syslog.h>
54 #include <sys/queue.h>
55 #include <sys/callout.h>
56 #include <sys/refcount.h>
59 #include <net/if_types.h>
60 #include <net/if_dl.h>
61 #include <net/if_var.h>
62 #include <net/route.h>
64 #include <net/radix_mpath.h>
68 #include <netinet/in.h>
69 #include <netinet/in_var.h>
70 #include <net/if_llatbl.h>
71 #define L3_ADDR_SIN6(le) ((struct sockaddr_in6 *) L3_ADDR(le))
72 #include <netinet6/in6_var.h>
73 #include <netinet6/in6_ifattach.h>
74 #include <netinet/ip6.h>
75 #include <netinet6/ip6_var.h>
76 #include <netinet6/scope6_var.h>
77 #include <netinet6/nd6.h>
78 #include <netinet/icmp6.h>
79 #include <netinet/ip_carp.h>
80 #include <netinet6/send.h>
82 #define SDL(s) ((struct sockaddr_dl *)s)
85 static struct dadq *nd6_dad_find(struct ifaddr *, struct nd_opt_nonce *);
86 static void nd6_dad_add(struct dadq *dp);
87 static void nd6_dad_del(struct dadq *dp);
88 static void nd6_dad_rele(struct dadq *);
89 static void nd6_dad_starttimer(struct dadq *, int, int);
90 static void nd6_dad_stoptimer(struct dadq *);
91 static void nd6_dad_timer(struct dadq *);
92 static void nd6_dad_duplicated(struct ifaddr *, struct dadq *);
93 static void nd6_dad_ns_output(struct dadq *);
94 static void nd6_dad_ns_input(struct ifaddr *, struct nd_opt_nonce *);
95 static void nd6_dad_na_input(struct ifaddr *);
96 static void nd6_na_output_fib(struct ifnet *, const struct in6_addr *,
97 const struct in6_addr *, u_long, int, struct sockaddr *, u_int);
98 static void nd6_ns_output_fib(struct ifnet *, const struct in6_addr *,
99 const struct in6_addr *, struct llentry *, uint8_t *, u_int);
101 static VNET_DEFINE(int, dad_enhanced) = 1;
102 #define V_dad_enhanced VNET(dad_enhanced)
104 SYSCTL_DECL(_net_inet6_ip6);
105 SYSCTL_INT(_net_inet6_ip6, OID_AUTO, dad_enhanced, CTLFLAG_VNET | CTLFLAG_RW,
106 &VNET_NAME(dad_enhanced), 0,
107 "Enable Enhanced DAD, which adds a random nonce to NS messages for DAD.");
109 static VNET_DEFINE(int, dad_maxtry) = 15; /* max # of *tries* to
110 transmit DAD packet */
111 #define V_dad_maxtry VNET(dad_maxtry)
114 * Input a Neighbor Solicitation Message.
117 * Based on RFC 2462 (duplicate address detection)
120 nd6_ns_input(struct mbuf *m, int off, int icmp6len)
122 struct ifnet *ifp = m->m_pkthdr.rcvif;
123 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
124 struct nd_neighbor_solicit *nd_ns;
125 struct in6_addr saddr6 = ip6->ip6_src;
126 struct in6_addr daddr6 = ip6->ip6_dst;
127 struct in6_addr taddr6;
128 struct in6_addr myaddr6;
130 struct ifaddr *ifa = NULL;
132 int anycast = 0, proxy = 0, tentative = 0;
135 union nd_opts ndopts;
136 struct sockaddr_dl proxydl;
137 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
139 rflag = (V_ip6_forwarding) ? ND_NA_FLAG_ROUTER : 0;
140 if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV && V_ip6_norbit_raif)
142 #ifndef PULLDOWN_TEST
143 IP6_EXTHDR_CHECK(m, off, icmp6len,);
144 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off);
146 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len);
148 ICMP6STAT_INC(icp6s_tooshort);
152 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */
153 taddr6 = nd_ns->nd_ns_target;
154 if (in6_setscope(&taddr6, ifp, NULL) != 0)
157 if (ip6->ip6_hlim != 255) {
159 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n",
160 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
161 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
165 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
166 /* dst has to be a solicited node multicast address. */
167 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL &&
168 /* don't check ifindex portion */
169 daddr6.s6_addr32[1] == 0 &&
170 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE &&
171 daddr6.s6_addr8[12] == 0xff) {
174 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
175 "(wrong ip6 dst)\n"));
178 } else if (!V_nd6_onlink_ns_rfc4861) {
179 struct sockaddr_in6 src_sa6;
182 * According to recent IETF discussions, it is not a good idea
183 * to accept a NS from an address which would not be deemed
184 * to be a neighbor otherwise. This point is expected to be
185 * clarified in future revisions of the specification.
187 bzero(&src_sa6, sizeof(src_sa6));
188 src_sa6.sin6_family = AF_INET6;
189 src_sa6.sin6_len = sizeof(src_sa6);
190 src_sa6.sin6_addr = saddr6;
191 if (nd6_is_addr_neighbor(&src_sa6, ifp) == 0) {
192 nd6log((LOG_INFO, "nd6_ns_input: "
193 "NS packet from non-neighbor\n"));
198 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
199 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n"));
203 icmp6len -= sizeof(*nd_ns);
204 nd6_option_init(nd_ns + 1, icmp6len, &ndopts);
205 if (nd6_options(&ndopts) < 0) {
207 "nd6_ns_input: invalid ND option, ignored\n"));
208 /* nd6_options have incremented stats */
212 if (ndopts.nd_opts_src_lladdr) {
213 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
214 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
217 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) {
218 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
219 "(link-layer address option)\n"));
224 * Attaching target link-layer address to the NA?
227 * NS IP dst is unicast/anycast MUST NOT add
228 * NS IP dst is solicited-node multicast MUST add
230 * In implementation, we add target link-layer address by default.
231 * We do not add one in MUST NOT cases.
233 if (!IN6_IS_ADDR_MULTICAST(&daddr6))
239 * Target address (taddr6) must be either:
240 * (1) Valid unicast/anycast address for my receiving interface,
241 * (2) Unicast address for which I'm offering proxy service, or
242 * (3) "tentative" address on which DAD is being performed.
244 /* (1) and (3) check. */
246 ifa = (*carp_iamatch6_p)(ifp, &taddr6);
248 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
255 bzero(&ro, sizeof(ro));
256 ro.ro_dst.sin6_len = sizeof(struct sockaddr_in6);
257 ro.ro_dst.sin6_family = AF_INET6;
258 ro.ro_dst.sin6_addr = taddr6;
260 /* Always use the default FIB. */
262 rtalloc_mpath_fib((struct route *)&ro, RTF_ANNOUNCE,
265 in6_rtalloc(&ro, RT_DEFAULT_FIB);
267 need_proxy = (ro.ro_rt &&
268 (ro.ro_rt->rt_flags & RTF_ANNOUNCE) != 0 &&
269 ro.ro_rt->rt_gateway->sa_family == AF_LINK);
270 if (ro.ro_rt != NULL) {
272 proxydl = *SDL(ro.ro_rt->rt_gateway);
277 * proxy NDP for single entry
279 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp,
280 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
287 * We've got an NS packet, and we don't have that adddress
288 * assigned for us. We MUST silently ignore it.
293 myaddr6 = *IFA_IN6(ifa);
294 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST;
295 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE;
296 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED)
299 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
300 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s "
301 "(if %d, NS packet %d)\n",
302 ip6_sprintf(ip6bufs, &taddr6),
303 ifp->if_addrlen, lladdrlen - 2));
307 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) {
308 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n",
309 ip6_sprintf(ip6bufs, &saddr6)));
314 * We have neighbor solicitation packet, with target address equals to
315 * one of my tentative address.
317 * src addr how to process?
319 * multicast of course, invalid (rejected in ip6_input)
320 * unicast somebody is doing address resolution -> ignore
321 * unspec dup address detection
323 * The processing is defined in RFC 2462.
327 * If source address is unspecified address, it is for
328 * duplicate address detection.
330 * If not, the packet is for addess resolution;
331 * silently ignore it.
333 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6))
334 nd6_dad_ns_input(ifa, ndopts.nd_opts_nonce);
340 * If the source address is unspecified address, entries must not
341 * be created or updated.
342 * It looks that sender is performing DAD. Output NA toward
343 * all-node multicast address, to tell the sender that I'm using
345 * S bit ("solicited") must be zero.
347 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
348 struct in6_addr in6_all;
350 in6_all = in6addr_linklocal_allnodes;
351 if (in6_setscope(&in6_all, ifp, NULL) != 0)
353 nd6_na_output_fib(ifp, &in6_all, &taddr6,
354 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
355 rflag, tlladdr, proxy ? (struct sockaddr *)&proxydl : NULL,
360 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen,
361 ND_NEIGHBOR_SOLICIT, 0);
363 nd6_na_output_fib(ifp, &saddr6, &taddr6,
364 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
365 rflag | ND_NA_FLAG_SOLICITED, tlladdr,
366 proxy ? (struct sockaddr *)&proxydl : NULL, M_GETFIB(m));
374 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n",
375 ip6_sprintf(ip6bufs, &saddr6)));
376 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n",
377 ip6_sprintf(ip6bufs, &daddr6)));
378 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n",
379 ip6_sprintf(ip6bufs, &taddr6)));
380 ICMP6STAT_INC(icp6s_badns);
387 * Output a Neighbor Solicitation Message. Caller specifies:
388 * - ICMP6 header source IP6 address
389 * - ND6 header target IP6 address
390 * - ND6 header source datalink address
393 * Based on RFC 2462 (duplicate address detection)
395 * ln - for source address determination
396 * nonce - If non-NULL, NS is used for duplicate address detection and
397 * the value (length is ND_OPT_NONCE_LEN) is used as a random nonce.
400 nd6_ns_output_fib(struct ifnet *ifp, const struct in6_addr *daddr6,
401 const struct in6_addr *taddr6, struct llentry *ln, uint8_t *nonce,
407 struct nd_neighbor_solicit *nd_ns;
408 struct ip6_moptions im6o;
414 if (IN6_IS_ADDR_MULTICAST(taddr6))
417 /* estimate the size of message */
418 maxlen = sizeof(*ip6) + sizeof(*nd_ns);
419 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
420 KASSERT(max_linkhdr + maxlen <= MCLBYTES, (
421 "%s: max_linkhdr + maxlen > MCLBYTES (%d + %d > %d)",
422 __func__, max_linkhdr, maxlen, MCLBYTES));
425 if (max_linkhdr + maxlen > MHLEN)
426 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
428 m = m_gethdr(M_NOWAIT, MT_DATA);
433 bzero(&ro, sizeof(ro));
435 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) {
436 m->m_flags |= M_MCAST;
437 im6o.im6o_multicast_ifp = ifp;
438 im6o.im6o_multicast_hlim = 255;
439 im6o.im6o_multicast_loop = 0;
442 icmp6len = sizeof(*nd_ns);
443 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len;
444 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
446 /* fill neighbor solicitation packet */
447 ip6 = mtod(m, struct ip6_hdr *);
449 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
450 ip6->ip6_vfc |= IPV6_VERSION;
451 /* ip6->ip6_plen will be set later */
452 ip6->ip6_nxt = IPPROTO_ICMPV6;
455 ip6->ip6_dst = *daddr6;
457 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
458 ip6->ip6_dst.s6_addr16[1] = 0;
459 ip6->ip6_dst.s6_addr32[1] = 0;
460 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE;
461 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3];
462 ip6->ip6_dst.s6_addr8[12] = 0xff;
463 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0)
471 * "If the source address of the packet prompting the
472 * solicitation is the same as one of the addresses assigned
473 * to the outgoing interface, that address SHOULD be placed
474 * in the IP Source Address of the outgoing solicitation.
475 * Otherwise, any one of the addresses assigned to the
476 * interface should be used."
478 * We use the source address for the prompting packet
480 * - saddr6 is given from the caller (by giving "ln"), and
481 * - saddr6 belongs to the outgoing interface.
482 * Otherwise, we perform the source address selection as usual.
484 struct in6_addr *hsrc;
489 if (ln->la_hold != NULL) {
490 struct ip6_hdr *hip6; /* hold ip6 */
493 * assuming every packet in la_hold has the same IP
496 hip6 = mtod(ln->la_hold, struct ip6_hdr *);
498 if (sizeof(*hip6) < ln->la_hold->m_len) {
499 ip6->ip6_src = hip6->ip6_src;
500 hsrc = &hip6->ip6_src;
505 if (hsrc && (ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp,
507 /* ip6_src set already. */
511 struct sockaddr_in6 dst_sa;
512 struct in6_addr src_in;
515 bzero(&dst_sa, sizeof(dst_sa));
516 dst_sa.sin6_family = AF_INET6;
517 dst_sa.sin6_len = sizeof(dst_sa);
518 dst_sa.sin6_addr = ip6->ip6_dst;
521 error = in6_selectsrc(&dst_sa, NULL,
522 NULL, &ro, NULL, &oifp, &src_in);
524 char ip6buf[INET6_ADDRSTRLEN];
525 nd6log((LOG_DEBUG, "%s: source can't be "
526 "determined: dst=%s, error=%d\n", __func__,
527 ip6_sprintf(ip6buf, &dst_sa.sin6_addr),
531 ip6->ip6_src = src_in;
535 * Source address for DAD packet must always be IPv6
536 * unspecified address. (0::0)
537 * We actually don't have to 0-clear the address (we did it
538 * above), but we do so here explicitly to make the intention
541 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src));
543 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1);
544 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT;
545 nd_ns->nd_ns_code = 0;
546 nd_ns->nd_ns_reserved = 0;
547 nd_ns->nd_ns_target = *taddr6;
548 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */
551 * Add source link-layer address option.
553 * spec implementation
555 * DAD packet MUST NOT do not add the option
556 * there's no link layer address:
557 * impossible do not add the option
558 * there's link layer address:
559 * Multicast NS MUST add one add the option
560 * Unicast NS SHOULD add one add the option
562 if (nonce == NULL && (mac = nd6_ifptomac(ifp))) {
563 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
564 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
565 /* 8 byte alignments... */
566 optlen = (optlen + 7) & ~7;
568 m->m_pkthdr.len += optlen;
571 bzero((caddr_t)nd_opt, optlen);
572 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR;
573 nd_opt->nd_opt_len = optlen >> 3;
574 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
577 * Add a Nonce option (RFC 3971) to detect looped back NS messages.
578 * This behavior is documented as Enhanced Duplicate Address
579 * Detection in RFC 7527.
580 * net.inet6.ip6.dad_enhanced=0 disables this.
582 if (V_dad_enhanced != 0 && nonce != NULL) {
583 int optlen = sizeof(struct nd_opt_hdr) + ND_OPT_NONCE_LEN;
584 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
585 /* 8-byte alignment is required. */
586 optlen = (optlen + 7) & ~7;
588 m->m_pkthdr.len += optlen;
591 bzero((caddr_t)nd_opt, optlen);
592 nd_opt->nd_opt_type = ND_OPT_NONCE;
593 nd_opt->nd_opt_len = optlen >> 3;
594 bcopy(nonce, (caddr_t)(nd_opt + 1), ND_OPT_NONCE_LEN);
596 ip6->ip6_plen = htons((u_short)icmp6len);
597 nd_ns->nd_ns_cksum = 0;
599 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len);
601 if (send_sendso_input_hook != NULL) {
602 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING,
603 sizeof(unsigned short), M_NOWAIT);
606 *(unsigned short *)(mtag + 1) = nd_ns->nd_ns_type;
607 m_tag_prepend(m, mtag);
610 ip6_output(m, NULL, &ro, (nonce != NULL) ? IPV6_UNSPECSRC : 0,
612 icmp6_ifstat_inc(ifp, ifs6_out_msg);
613 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit);
614 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_SOLICIT]);
616 /* We don't cache this route. */
630 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6,
631 const struct in6_addr *taddr6, struct llentry *ln, uint8_t *nonce)
634 nd6_ns_output_fib(ifp, daddr6, taddr6, ln, 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)
650 struct ifnet *ifp = m->m_pkthdr.rcvif;
651 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
652 struct nd_neighbor_advert *nd_na;
653 struct in6_addr daddr6 = ip6->ip6_dst;
654 struct in6_addr taddr6;
663 struct llentry *ln = NULL;
664 union nd_opts ndopts;
665 struct mbuf *chain = NULL;
666 struct sockaddr_in6 sin6;
667 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
669 if (ip6->ip6_hlim != 255) {
671 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n",
672 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
673 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
677 #ifndef PULLDOWN_TEST
678 IP6_EXTHDR_CHECK(m, off, icmp6len,);
679 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off);
681 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len);
683 ICMP6STAT_INC(icp6s_tooshort);
688 flags = nd_na->nd_na_flags_reserved;
689 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0);
690 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0);
691 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0);
692 memset(&sin6, 0, sizeof(sin6));
694 taddr6 = nd_na->nd_na_target;
695 if (in6_setscope(&taddr6, ifp, NULL))
696 goto bad; /* XXX: impossible */
698 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
700 "nd6_na_input: invalid target address %s\n",
701 ip6_sprintf(ip6bufs, &taddr6)));
704 if (IN6_IS_ADDR_MULTICAST(&daddr6))
707 "nd6_na_input: a solicited adv is multicasted\n"));
711 icmp6len -= sizeof(*nd_na);
712 nd6_option_init(nd_na + 1, icmp6len, &ndopts);
713 if (nd6_options(&ndopts) < 0) {
715 "nd6_na_input: invalid ND option, ignored\n"));
716 /* nd6_options have incremented stats */
720 if (ndopts.nd_opts_tgt_lladdr) {
721 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
722 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
726 * This effectively disables the DAD check on a non-master CARP
730 ifa = (*carp_iamatch6_p)(ifp, &taddr6);
732 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
735 * Target address matches one of my interface address.
737 * If my address is tentative, this means that there's somebody
738 * already using the same address as mine. This indicates DAD failure.
739 * This is defined in RFC 2462.
741 * Otherwise, process as defined in RFC 2461.
744 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) {
745 nd6_dad_na_input(ifa);
750 /* Just for safety, maybe unnecessary. */
754 "nd6_na_input: duplicate IP6 address %s\n",
755 ip6_sprintf(ip6bufs, &taddr6));
759 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
760 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s "
761 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6),
762 ifp->if_addrlen, lladdrlen - 2));
767 * If no neighbor cache entry is found, NA SHOULD silently be
770 IF_AFDATA_RLOCK(ifp);
771 ln = nd6_lookup(&taddr6, LLE_EXCLUSIVE, ifp);
772 IF_AFDATA_RUNLOCK(ifp);
777 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
779 * If the link-layer has address, and no lladdr option came,
780 * discard the packet.
782 if (ifp->if_addrlen && lladdr == NULL) {
787 * Record link-layer address, and update the state.
789 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen);
790 ln->la_flags |= LLE_VALID;
791 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED);
793 ln->ln_state = ND6_LLINFO_REACHABLE;
795 if (!ND6_LLINFO_PERMANENT(ln)) {
796 nd6_llinfo_settimer_locked(ln,
797 (long)ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz);
800 ln->ln_state = ND6_LLINFO_STALE;
801 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz);
803 if ((ln->ln_router = is_router) != 0) {
805 * This means a router's state has changed from
806 * non-reachable to probably reachable, and might
807 * affect the status of associated prefixes..
815 * Check if the link-layer address has changed or not.
820 if (ln->la_flags & LLE_VALID) {
821 if (bcmp(lladdr, &ln->ll_addr, ifp->if_addrlen))
830 * This is VERY complex. Look at it with care.
832 * override solicit lladdr llchange action
837 * 0 0 y y (1) REACHABLE->STALE
838 * 0 1 n -- (2c) *->REACHABLE
839 * 0 1 y n (2b) L *->REACHABLE
840 * 0 1 y y (1) REACHABLE->STALE
843 * 1 0 y y (2a) L *->STALE
844 * 1 1 n -- (2a) *->REACHABLE
845 * 1 1 y n (2a) L *->REACHABLE
846 * 1 1 y y (2a) L *->REACHABLE
848 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */
850 * If state is REACHABLE, make it STALE.
851 * no other updates should be done.
853 if (ln->ln_state == ND6_LLINFO_REACHABLE) {
854 ln->ln_state = ND6_LLINFO_STALE;
855 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz);
858 } else if (is_override /* (2a) */
859 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */
860 || lladdr == NULL) { /* (2c) */
862 * Update link-local address, if any.
864 if (lladdr != NULL) {
865 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen);
866 ln->la_flags |= LLE_VALID;
867 EVENTHANDLER_INVOKE(lle_event, ln,
872 * If solicited, make the state REACHABLE.
873 * If not solicited and the link-layer address was
874 * changed, make it STALE.
877 ln->ln_state = ND6_LLINFO_REACHABLE;
879 if (!ND6_LLINFO_PERMANENT(ln)) {
880 nd6_llinfo_settimer_locked(ln,
881 (long)ND_IFINFO(ifp)->reachable * hz);
884 if (lladdr != NULL && llchange) {
885 ln->ln_state = ND6_LLINFO_STALE;
886 nd6_llinfo_settimer_locked(ln,
887 (long)V_nd6_gctimer * hz);
892 if (ln->ln_router && !is_router) {
894 * The peer dropped the router flag.
895 * Remove the sender from the Default Router List and
896 * update the Destination Cache entries.
898 struct nd_defrouter *dr;
899 struct in6_addr *in6;
901 in6 = &L3_ADDR_SIN6(ln)->sin6_addr;
903 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp);
906 else if (ND_IFINFO(ln->lle_tbl->llt_ifp)->flags &
907 ND6_IFF_ACCEPT_RTADV) {
909 * Even if the neighbor is not in the default
910 * router list, the neighbor may be used
911 * as a next hop for some destinations
912 * (e.g. redirect case). So we must
913 * call rt6_flush explicitly.
915 rt6_flush(&ip6->ip6_src, ifp);
918 ln->ln_router = is_router;
922 * rt->rt_flags &= ~RTF_REJECT;
925 if (ln->la_hold != NULL)
926 nd6_grab_holdchain(ln, &chain, &sin6);
932 nd6_flush_holdchain(ifp, ifp, chain, &sin6);
935 pfxlist_onlink_check();
944 ICMP6STAT_INC(icp6s_badna);
949 * Neighbor advertisement output handling.
953 * the following items are not implemented yet:
954 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
955 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
957 * tlladdr - 1 if include target link-layer address
958 * sdl0 - sockaddr_dl (= proxy NA) or NULL
961 nd6_na_output_fib(struct ifnet *ifp, const struct in6_addr *daddr6_0,
962 const struct in6_addr *taddr6, u_long flags, int tlladdr,
963 struct sockaddr *sdl0, u_int fibnum)
969 struct nd_neighbor_advert *nd_na;
970 struct ip6_moptions im6o;
971 struct in6_addr src, daddr6;
972 struct sockaddr_in6 dst_sa;
973 int icmp6len, maxlen, error;
977 bzero(&ro, sizeof(ro));
979 daddr6 = *daddr6_0; /* make a local copy for modification */
981 /* estimate the size of message */
982 maxlen = sizeof(*ip6) + sizeof(*nd_na);
983 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
984 KASSERT(max_linkhdr + maxlen <= MCLBYTES, (
985 "%s: max_linkhdr + maxlen > MCLBYTES (%d + %d > %d)",
986 __func__, max_linkhdr, maxlen, MCLBYTES));
988 if (max_linkhdr + maxlen > MHLEN)
989 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
991 m = m_gethdr(M_NOWAIT, MT_DATA);
996 if (IN6_IS_ADDR_MULTICAST(&daddr6)) {
997 m->m_flags |= M_MCAST;
998 im6o.im6o_multicast_ifp = ifp;
999 im6o.im6o_multicast_hlim = 255;
1000 im6o.im6o_multicast_loop = 0;
1003 icmp6len = sizeof(*nd_na);
1004 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len;
1005 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
1007 /* fill neighbor advertisement packet */
1008 ip6 = mtod(m, struct ip6_hdr *);
1010 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
1011 ip6->ip6_vfc |= IPV6_VERSION;
1012 ip6->ip6_nxt = IPPROTO_ICMPV6;
1013 ip6->ip6_hlim = 255;
1014 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) {
1016 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
1017 daddr6.s6_addr16[1] = 0;
1018 daddr6.s6_addr32[1] = 0;
1019 daddr6.s6_addr32[2] = 0;
1020 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE;
1021 if (in6_setscope(&daddr6, ifp, NULL))
1024 flags &= ~ND_NA_FLAG_SOLICITED;
1026 ip6->ip6_dst = daddr6;
1027 bzero(&dst_sa, sizeof(struct sockaddr_in6));
1028 dst_sa.sin6_family = AF_INET6;
1029 dst_sa.sin6_len = sizeof(struct sockaddr_in6);
1030 dst_sa.sin6_addr = daddr6;
1033 * Select a source whose scope is the same as that of the dest.
1035 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa));
1037 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &oifp, &src);
1039 char ip6buf[INET6_ADDRSTRLEN];
1040 nd6log((LOG_DEBUG, "nd6_na_output: source can't be "
1041 "determined: dst=%s, error=%d\n",
1042 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error));
1046 nd_na = (struct nd_neighbor_advert *)(ip6 + 1);
1047 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT;
1048 nd_na->nd_na_code = 0;
1049 nd_na->nd_na_target = *taddr6;
1050 in6_clearscope(&nd_na->nd_na_target); /* XXX */
1053 * "tlladdr" indicates NS's condition for adding tlladdr or not.
1054 * see nd6_ns_input() for details.
1055 * Basically, if NS packet is sent to unicast/anycast addr,
1056 * target lladdr option SHOULD NOT be included.
1060 * sdl0 != NULL indicates proxy NA. If we do proxy, use
1061 * lladdr in sdl0. If we are not proxying (sending NA for
1062 * my address) use lladdr configured for the interface.
1066 mac = (*carp_macmatch6_p)(ifp, m, taddr6);
1068 mac = nd6_ifptomac(ifp);
1069 } else if (sdl0->sa_family == AF_LINK) {
1070 struct sockaddr_dl *sdl;
1071 sdl = (struct sockaddr_dl *)sdl0;
1072 if (sdl->sdl_alen == ifp->if_addrlen)
1076 if (tlladdr && mac) {
1077 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
1078 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1);
1080 /* roundup to 8 bytes alignment! */
1081 optlen = (optlen + 7) & ~7;
1083 m->m_pkthdr.len += optlen;
1086 bzero((caddr_t)nd_opt, optlen);
1087 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
1088 nd_opt->nd_opt_len = optlen >> 3;
1089 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
1091 flags &= ~ND_NA_FLAG_OVERRIDE;
1093 ip6->ip6_plen = htons((u_short)icmp6len);
1094 nd_na->nd_na_flags_reserved = flags;
1095 nd_na->nd_na_cksum = 0;
1096 nd_na->nd_na_cksum =
1097 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len);
1099 if (send_sendso_input_hook != NULL) {
1100 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING,
1101 sizeof(unsigned short), M_NOWAIT);
1104 *(unsigned short *)(mtag + 1) = nd_na->nd_na_type;
1105 m_tag_prepend(m, mtag);
1108 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL);
1109 icmp6_ifstat_inc(ifp, ifs6_out_msg);
1110 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert);
1111 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]);
1113 /* We don't cache this route. */
1125 #ifndef BURN_BRIDGES
1127 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0,
1128 const struct in6_addr *taddr6, u_long flags, int tlladdr,
1129 struct sockaddr *sdl0)
1132 nd6_na_output_fib(ifp, daddr6_0, taddr6, flags, tlladdr, sdl0,
1138 nd6_ifptomac(struct ifnet *ifp)
1140 switch (ifp->if_type) {
1148 #ifdef IFT_IEEE80211
1151 case IFT_INFINIBAND:
1154 return IF_LLADDR(ifp);
1161 TAILQ_ENTRY(dadq) dad_list;
1162 struct ifaddr *dad_ifa;
1163 int dad_count; /* max NS to send */
1164 int dad_ns_tcount; /* # of trials to send NS */
1165 int dad_ns_ocount; /* NS sent so far */
1168 int dad_ns_lcount; /* looped back NS */
1169 int dad_loopbackprobe; /* probing state for loopback detection */
1170 struct callout dad_timer_ch;
1171 struct vnet *dad_vnet;
1173 #define ND_OPT_NONCE_LEN32 \
1174 ((ND_OPT_NONCE_LEN + sizeof(uint32_t) - 1)/sizeof(uint32_t))
1175 uint32_t dad_nonce[ND_OPT_NONCE_LEN32];
1178 static VNET_DEFINE(TAILQ_HEAD(, dadq), dadq);
1179 static VNET_DEFINE(struct rwlock, dad_rwlock);
1180 #define V_dadq VNET(dadq)
1181 #define V_dad_rwlock VNET(dad_rwlock)
1183 #define DADQ_RLOCK() rw_rlock(&V_dad_rwlock)
1184 #define DADQ_RUNLOCK() rw_runlock(&V_dad_rwlock)
1185 #define DADQ_WLOCK() rw_wlock(&V_dad_rwlock)
1186 #define DADQ_WUNLOCK() rw_wunlock(&V_dad_rwlock)
1189 nd6_dad_add(struct dadq *dp)
1193 TAILQ_INSERT_TAIL(&V_dadq, dp, dad_list);
1198 nd6_dad_del(struct dadq *dp)
1202 TAILQ_REMOVE(&V_dadq, dp, dad_list);
1207 static struct dadq *
1208 nd6_dad_find(struct ifaddr *ifa, struct nd_opt_nonce *n)
1213 TAILQ_FOREACH(dp, &V_dadq, dad_list) {
1214 if (dp->dad_ifa != ifa)
1217 * Skip if the nonce matches the received one.
1218 * +2 in the length is required because of type and
1219 * length fields are included in a header.
1222 n->nd_opt_nonce_len == (ND_OPT_NONCE_LEN + 2) / 8 &&
1223 memcmp(&n->nd_opt_nonce[0], &dp->dad_nonce[0],
1224 ND_OPT_NONCE_LEN) == 0) {
1225 dp->dad_ns_lcount++;
1228 refcount_acquire(&dp->dad_refcnt);
1237 nd6_dad_starttimer(struct dadq *dp, int ticks, int send_ns)
1241 nd6_dad_ns_output(dp);
1242 callout_reset(&dp->dad_timer_ch, ticks,
1243 (void (*)(void *))nd6_dad_timer, (void *)dp);
1247 nd6_dad_stoptimer(struct dadq *dp)
1250 callout_drain(&dp->dad_timer_ch);
1254 nd6_dad_rele(struct dadq *dp)
1257 if (refcount_release(&dp->dad_refcnt)) {
1258 ifa_free(dp->dad_ifa);
1267 rw_init(&V_dad_rwlock, "nd6 DAD queue");
1268 TAILQ_INIT(&V_dadq);
1272 * Start Duplicate Address Detection (DAD) for specified interface address.
1275 nd6_dad_start(struct ifaddr *ifa, int delay)
1277 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1279 char ip6buf[INET6_ADDRSTRLEN];
1283 * If we don't need DAD, don't do it.
1284 * There are several cases:
1285 * - DAD is disabled (ip6_dad_count == 0)
1286 * - the interface address is anycast
1288 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
1290 "nd6_dad_start: called with non-tentative address "
1292 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1293 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1296 if (ia->ia6_flags & IN6_IFF_ANYCAST) {
1297 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1300 if (!V_ip6_dad_count) {
1301 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1304 if (ifa->ifa_ifp == NULL)
1305 panic("nd6_dad_start: ifa->ifa_ifp == NULL");
1306 if (ND_IFINFO(ifa->ifa_ifp)->flags & ND6_IFF_NO_DAD) {
1307 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1310 if (!(ifa->ifa_ifp->if_flags & IFF_UP) ||
1311 !(ifa->ifa_ifp->if_drv_flags & IFF_DRV_RUNNING) ||
1312 (ND_IFINFO(ifa->ifa_ifp)->flags & ND6_IFF_IFDISABLED)) {
1313 ia->ia6_flags |= IN6_IFF_TENTATIVE;
1316 if ((dp = nd6_dad_find(ifa, NULL)) != NULL) {
1318 * DAD is already in progress. Let the existing entry
1325 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT | M_ZERO);
1327 log(LOG_ERR, "nd6_dad_start: memory allocation failed for "
1329 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1330 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1333 callout_init(&dp->dad_timer_ch, 0);
1335 dp->dad_vnet = curvnet;
1337 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp),
1338 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1341 * Send NS packet for DAD, ip6_dad_count times.
1342 * Note that we must delay the first transmission, if this is the
1343 * first packet to be sent from the interface after interface
1344 * (re)initialization.
1347 ifa_ref(dp->dad_ifa);
1348 dp->dad_count = V_ip6_dad_count;
1349 dp->dad_ns_icount = dp->dad_na_icount = 0;
1350 dp->dad_ns_ocount = dp->dad_ns_tcount = 0;
1351 dp->dad_ns_lcount = dp->dad_loopbackprobe = 0;
1352 refcount_init(&dp->dad_refcnt, 1);
1357 delay = (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000;
1359 nd6_dad_starttimer(dp, delay, send_ns);
1363 * terminate DAD unconditionally. used for address removals.
1366 nd6_dad_stop(struct ifaddr *ifa)
1370 dp = nd6_dad_find(ifa, NULL);
1372 /* DAD wasn't started yet */
1376 nd6_dad_stoptimer(dp);
1379 * The DAD queue entry may have been removed by nd6_dad_timer() while
1380 * we were waiting for it to stop, so re-do the lookup.
1383 if (nd6_dad_find(ifa, NULL) == NULL)
1391 nd6_dad_timer(struct dadq *dp)
1393 CURVNET_SET(dp->dad_vnet);
1394 struct ifaddr *ifa = dp->dad_ifa;
1395 struct ifnet *ifp = dp->dad_ifa->ifa_ifp;
1396 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1397 char ip6buf[INET6_ADDRSTRLEN];
1401 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n");
1404 if (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) {
1405 /* Do not need DAD for ifdisabled interface. */
1406 log(LOG_ERR, "nd6_dad_timer: cancel DAD on %s because of "
1407 "ND6_IFF_IFDISABLED.\n", ifp->if_xname);
1410 if (ia->ia6_flags & IN6_IFF_DUPLICATED) {
1411 log(LOG_ERR, "nd6_dad_timer: called with duplicated address "
1413 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1414 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1417 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) {
1418 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address "
1420 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1421 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1425 /* Stop DAD if the interface is down even after dad_maxtry attempts. */
1426 if ((dp->dad_ns_tcount > V_dad_maxtry) &&
1427 (((ifp->if_flags & IFF_UP) == 0) ||
1428 ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0))) {
1429 nd6log((LOG_INFO, "%s: could not run DAD "
1430 "because the interface was down or not running.\n",
1431 if_name(ifa->ifa_ifp)));
1435 /* Need more checks? */
1436 if (dp->dad_ns_ocount < dp->dad_count) {
1438 * We have more NS to go. Send NS packet for DAD.
1440 nd6_dad_starttimer(dp,
1441 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000, 1);
1445 * We have transmitted sufficient number of DAD packets.
1446 * See what we've got.
1448 if (dp->dad_ns_icount > 0 || dp->dad_na_icount > 0)
1449 /* We've seen NS or NA, means DAD has failed. */
1450 nd6_dad_duplicated(ifa, dp);
1451 else if (V_dad_enhanced != 0 &&
1452 dp->dad_ns_lcount > 0 &&
1453 dp->dad_ns_lcount > dp->dad_loopbackprobe) {
1455 * Sec. 4.1 in RFC 7527 requires transmission of
1456 * additional probes until the loopback condition
1457 * becomes clear when a looped back probe is detected.
1459 log(LOG_ERR, "%s: a looped back NS message is "
1460 "detected during DAD for %s. "
1461 "Another DAD probes are being sent.\n",
1462 if_name(ifa->ifa_ifp),
1463 ip6_sprintf(ip6buf, IFA_IN6(ifa)));
1464 dp->dad_loopbackprobe = dp->dad_ns_lcount;
1466 * Send an NS immediately and increase dad_count by
1467 * V_nd6_mmaxtries - 1.
1470 dp->dad_ns_ocount + V_nd6_mmaxtries - 1;
1471 nd6_dad_starttimer(dp,
1472 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000,
1477 * We are done with DAD. No NA came, no NS came.
1478 * No duplicate address found. Check IFDISABLED flag
1479 * again in case that it is changed between the
1480 * beginning of this function and here.
1482 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) == 0)
1483 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1486 "%s: DAD complete for %s - no duplicates found\n",
1487 if_name(ifa->ifa_ifp),
1488 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1489 if (dp->dad_ns_lcount > 0)
1490 log(LOG_ERR, "%s: DAD completed while "
1491 "a looped back NS message is detected "
1492 "during DAD for %s.\n",
1493 if_name(ifa->ifa_ifp),
1494 ip6_sprintf(ip6buf, IFA_IN6(ifa)));
1504 nd6_dad_duplicated(struct ifaddr *ifa, struct dadq *dp)
1506 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1508 char ip6buf[INET6_ADDRSTRLEN];
1510 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: "
1511 "NS in/out/loopback=%d/%d/%d, NA in=%d\n",
1512 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1513 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_ns_lcount,
1516 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1517 ia->ia6_flags |= IN6_IFF_DUPLICATED;
1520 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n",
1521 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr));
1522 log(LOG_ERR, "%s: manual intervention required\n",
1526 * If the address is a link-local address formed from an interface
1527 * identifier based on the hardware address which is supposed to be
1528 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP
1529 * operation on the interface SHOULD be disabled.
1530 * [RFC 4862, Section 5.4.5]
1532 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) {
1533 struct in6_addr in6;
1536 * To avoid over-reaction, we only apply this logic when we are
1537 * very sure that hardware addresses are supposed to be unique.
1539 switch (ifp->if_type) {
1544 #ifdef IFT_IEEE80211
1547 case IFT_INFINIBAND:
1548 in6 = ia->ia_addr.sin6_addr;
1549 if (in6_get_hw_ifid(ifp, &in6) == 0 &&
1550 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) {
1551 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED;
1552 log(LOG_ERR, "%s: possible hardware address "
1553 "duplication detected, disable IPv6\n",
1562 nd6_dad_ns_output(struct dadq *dp)
1564 struct in6_ifaddr *ia = (struct in6_ifaddr *)dp->dad_ifa;
1565 struct ifnet *ifp = dp->dad_ifa->ifa_ifp;
1568 dp->dad_ns_tcount++;
1569 if ((ifp->if_flags & IFF_UP) == 0) {
1572 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
1576 dp->dad_ns_ocount++;
1577 if (V_dad_enhanced != 0) {
1578 for (i = 0; i < ND_OPT_NONCE_LEN32; i++)
1579 dp->dad_nonce[i] = arc4random();
1581 * XXXHRS: Note that in the case that
1582 * DupAddrDetectTransmits > 1, multiple NS messages with
1583 * different nonces can be looped back in an unexpected
1584 * order. The current implementation recognizes only
1585 * the latest nonce on the sender side. Practically it
1586 * should work well in almost all cases.
1589 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL,
1590 (uint8_t *)&dp->dad_nonce[0]);
1594 nd6_dad_ns_input(struct ifaddr *ifa, struct nd_opt_nonce *ndopt_nonce)
1596 struct in6_ifaddr *ia;
1598 const struct in6_addr *taddr6;
1602 panic("ifa == NULL in nd6_dad_ns_input");
1604 ia = (struct in6_ifaddr *)ifa;
1606 taddr6 = &ia->ia_addr.sin6_addr;
1607 /* Ignore Nonce option when Enhanced DAD is disabled. */
1608 if (V_dad_enhanced == 0)
1610 dp = nd6_dad_find(ifa, ndopt_nonce);
1614 dp->dad_ns_icount++;
1619 nd6_dad_na_input(struct ifaddr *ifa)
1624 panic("ifa == NULL in nd6_dad_na_input");
1626 dp = nd6_dad_find(ifa, NULL);
1628 dp->dad_na_icount++;