1 /*-
2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
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.
16 *
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
27 * SUCH DAMAGE.
28 *
29 * $KAME: nd6_nbr.c,v 1.86 2002/01/21 02:33:04 jinmei Exp $
30 */
31
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34
35 #include "opt_inet.h"
36 #include "opt_inet6.h"
37 #include "opt_ipsec.h"
38 #include "opt_carp.h"
39
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/malloc.h>
43 #include <sys/mbuf.h>
44 #include <sys/socket.h>
45 #include <sys/sockio.h>
46 #include <sys/time.h>
47 #include <sys/kernel.h>
48 #include <sys/errno.h>
49 #include <sys/syslog.h>
50 #include <sys/queue.h>
51 #include <sys/callout.h>
52
53 #include <net/if.h>
54 #include <net/if_types.h>
55 #include <net/if_dl.h>
56 #include <net/if_var.h>
57 #include <net/route.h>
58
59 #include <netinet/in.h>
60 #include <netinet/in_var.h>
61 #include <netinet6/in6_var.h>
62 #include <netinet6/in6_ifattach.h>
63 #include <netinet/ip6.h>
64 #include <netinet6/ip6_var.h>
65 #include <netinet6/scope6_var.h>
66 #include <netinet6/nd6.h>
67 #include <netinet/icmp6.h>
68
69 #ifdef DEV_CARP
70 #include <netinet/ip_carp.h>
71 #endif
72
73 #define SDL(s) ((struct sockaddr_dl *)s)
74
75 struct dadq;
76 static struct dadq *nd6_dad_find(struct ifaddr *);
77 static void nd6_dad_starttimer(struct dadq *, int);
78 static void nd6_dad_stoptimer(struct dadq *);
79 static void nd6_dad_timer(struct ifaddr *);
80 static void nd6_dad_ns_output(struct dadq *, struct ifaddr *);
81 static void nd6_dad_ns_input(struct ifaddr *);
82 static void nd6_dad_na_input(struct ifaddr *);
83
84 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/
85 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */
86
87 /*
88 * Input a Neighbor Solicitation Message.
89 *
90 * Based on RFC 2461
91 * Based on RFC 2462 (duplicate address detection)
92 */
93 void
94 nd6_ns_input(struct mbuf *m, int off, int icmp6len)
95 {
96 struct ifnet *ifp = m->m_pkthdr.rcvif;
97 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
98 struct nd_neighbor_solicit *nd_ns;
99 struct in6_addr saddr6 = ip6->ip6_src;
100 struct in6_addr daddr6 = ip6->ip6_dst;
101 struct in6_addr taddr6;
102 struct in6_addr myaddr6;
103 char *lladdr = NULL;
104 struct ifaddr *ifa = NULL;
105 int lladdrlen = 0;
106 int anycast = 0, proxy = 0, tentative = 0;
107 int tlladdr;
108 union nd_opts ndopts;
109 struct sockaddr_dl *proxydl = NULL;
110 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
111
112 #ifndef PULLDOWN_TEST
113 IP6_EXTHDR_CHECK(m, off, icmp6len,);
114 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off);
115 #else
116 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len);
117 if (nd_ns == NULL) {
118 icmp6stat.icp6s_tooshort++;
119 return;
120 }
121 #endif
122 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */
123 taddr6 = nd_ns->nd_ns_target;
124 if (in6_setscope(&taddr6, ifp, NULL) != 0)
125 goto bad;
126
127 if (ip6->ip6_hlim != 255) {
128 nd6log((LOG_ERR,
129 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n",
130 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
131 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
132 goto bad;
133 }
134
135 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
136 /* dst has to be a solicited node multicast address. */
137 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL &&
138 /* don't check ifindex portion */
139 daddr6.s6_addr32[1] == 0 &&
140 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE &&
141 daddr6.s6_addr8[12] == 0xff) {
142 ; /* good */
143 } else {
144 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
145 "(wrong ip6 dst)\n"));
146 goto bad;
147 }
148 } else if (!nd6_onlink_ns_rfc4861) {
149 struct sockaddr_in6 src_sa6;
150
151 /*
152 * According to recent IETF discussions, it is not a good idea
153 * to accept a NS from an address which would not be deemed
154 * to be a neighbor otherwise. This point is expected to be
155 * clarified in future revisions of the specification.
156 */
157 bzero(&src_sa6, sizeof(src_sa6));
158 src_sa6.sin6_family = AF_INET6;
159 src_sa6.sin6_len = sizeof(src_sa6);
160 src_sa6.sin6_addr = saddr6;
161 if (!nd6_is_addr_neighbor(&src_sa6, ifp)) {
162 nd6log((LOG_INFO, "nd6_ns_input: "
163 "NS packet from non-neighbor\n"));
164 goto bad;
165 }
166 }
167
168 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
169 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n"));
170 goto bad;
171 }
172
173 icmp6len -= sizeof(*nd_ns);
174 nd6_option_init(nd_ns + 1, icmp6len, &ndopts);
175 if (nd6_options(&ndopts) < 0) {
176 nd6log((LOG_INFO,
177 "nd6_ns_input: invalid ND option, ignored\n"));
178 /* nd6_options have incremented stats */
179 goto freeit;
180 }
181
182 if (ndopts.nd_opts_src_lladdr) {
183 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
184 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
185 }
186
187 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) {
188 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
189 "(link-layer address option)\n"));
190 goto bad;
191 }
192
193 /*
194 * Attaching target link-layer address to the NA?
195 * (RFC 2461 7.2.4)
196 *
197 * NS IP dst is unicast/anycast MUST NOT add
198 * NS IP dst is solicited-node multicast MUST add
199 *
200 * In implementation, we add target link-layer address by default.
201 * We do not add one in MUST NOT cases.
202 */
203 if (!IN6_IS_ADDR_MULTICAST(&daddr6))
204 tlladdr = 0;
205 else
206 tlladdr = 1;
207
208 /*
209 * Target address (taddr6) must be either:
210 * (1) Valid unicast/anycast address for my receiving interface,
211 * (2) Unicast address for which I'm offering proxy service, or
212 * (3) "tentative" address on which DAD is being performed.
213 */
214 /* (1) and (3) check. */
215 #ifdef DEV_CARP
216 if (ifp->if_carp)
217 ifa = carp_iamatch6(ifp->if_carp, &taddr6);
218 if (ifa == NULL)
219 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
220 #else
221 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
222 #endif
223
224 /* (2) check. */
225 if (ifa == NULL) {
226 struct rtentry *rt;
227 struct sockaddr_in6 tsin6;
228 int need_proxy;
229
230 bzero(&tsin6, sizeof tsin6);
231 tsin6.sin6_len = sizeof(struct sockaddr_in6);
232 tsin6.sin6_family = AF_INET6;
233 tsin6.sin6_addr = taddr6;
234
235 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0);
236 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 &&
237 rt->rt_gateway->sa_family == AF_LINK);
238 if (rt)
239 rtfree(rt);
240 if (need_proxy) {
241 /*
242 * proxy NDP for single entry
243 */
244 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp,
245 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
246 if (ifa) {
247 proxy = 1;
248 proxydl = SDL(rt->rt_gateway);
249 }
250 }
251 }
252 if (ifa == NULL) {
253 /*
254 * We've got an NS packet, and we don't have that adddress
255 * assigned for us. We MUST silently ignore it.
256 * See RFC2461 7.2.3.
257 */
258 goto freeit;
259 }
260 myaddr6 = *IFA_IN6(ifa);
261 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST;
262 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE;
263 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED)
264 goto freeit;
265
266 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
267 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s "
268 "(if %d, NS packet %d)\n",
269 ip6_sprintf(ip6bufs, &taddr6),
270 ifp->if_addrlen, lladdrlen - 2));
271 goto bad;
272 }
273
274 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) {
275 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n",
276 ip6_sprintf(ip6bufs, &saddr6)));
277 goto freeit;
278 }
279
280 /*
281 * We have neighbor solicitation packet, with target address equals to
282 * one of my tentative address.
283 *
284 * src addr how to process?
285 * --- ---
286 * multicast of course, invalid (rejected in ip6_input)
287 * unicast somebody is doing address resolution -> ignore
288 * unspec dup address detection
289 *
290 * The processing is defined in RFC 2462.
291 */
292 if (tentative) {
293 /*
294 * If source address is unspecified address, it is for
295 * duplicate address detection.
296 *
297 * If not, the packet is for addess resolution;
298 * silently ignore it.
299 */
300 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6))
301 nd6_dad_ns_input(ifa);
302
303 goto freeit;
304 }
305
306 /*
307 * If the source address is unspecified address, entries must not
308 * be created or updated.
309 * It looks that sender is performing DAD. Output NA toward
310 * all-node multicast address, to tell the sender that I'm using
311 * the address.
312 * S bit ("solicited") must be zero.
313 */
314 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
315 struct in6_addr in6_all;
316
317 in6_all = in6addr_linklocal_allnodes;
318 if (in6_setscope(&in6_all, ifp, NULL) != 0)
319 goto bad;
320 nd6_na_output(ifp, &in6_all, &taddr6,
321 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
322 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0),
323 tlladdr, (struct sockaddr *)proxydl);
324 goto freeit;
325 }
326
327 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen,
328 ND_NEIGHBOR_SOLICIT, 0);
329
330 nd6_na_output(ifp, &saddr6, &taddr6,
331 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
332 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED,
333 tlladdr, (struct sockaddr *)proxydl);
334 freeit:
335 m_freem(m);
336 return;
337
338 bad:
339 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n",
340 ip6_sprintf(ip6bufs, &saddr6)));
341 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n",
342 ip6_sprintf(ip6bufs, &daddr6)));
343 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n",
344 ip6_sprintf(ip6bufs, &taddr6)));
345 icmp6stat.icp6s_badns++;
346 m_freem(m);
347 }
348
349 /*
350 * Output a Neighbor Solicitation Message. Caller specifies:
351 * - ICMP6 header source IP6 address
352 * - ND6 header target IP6 address
353 * - ND6 header source datalink address
354 *
355 * Based on RFC 2461
356 * Based on RFC 2462 (duplicate address detection)
357 *
358 * ln - for source address determination
359 * dad - duplicate address detection
360 */
361 void
362 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6,
363 const struct in6_addr *taddr6, struct llinfo_nd6 *ln, int dad)
364 {
365 struct mbuf *m;
366 struct ip6_hdr *ip6;
367 struct nd_neighbor_solicit *nd_ns;
368 struct in6_addr *src, src_in;
369 struct ip6_moptions im6o;
370 int icmp6len;
371 int maxlen;
372 caddr_t mac;
373 struct route_in6 ro;
374
375 bzero(&ro, sizeof(ro));
376
377 if (IN6_IS_ADDR_MULTICAST(taddr6))
378 return;
379
380 /* estimate the size of message */
381 maxlen = sizeof(*ip6) + sizeof(*nd_ns);
382 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
383 if (max_linkhdr + maxlen >= MCLBYTES) {
384 #ifdef DIAGNOSTIC
385 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES "
386 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
387 #endif
388 return;
389 }
390
391 MGETHDR(m, M_DONTWAIT, MT_DATA);
392 if (m && max_linkhdr + maxlen >= MHLEN) {
393 MCLGET(m, M_DONTWAIT);
394 if ((m->m_flags & M_EXT) == 0) {
395 m_free(m);
396 m = NULL;
397 }
398 }
399 if (m == NULL)
400 return;
401 m->m_pkthdr.rcvif = NULL;
402
403 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) {
404 m->m_flags |= M_MCAST;
405 im6o.im6o_multicast_ifp = ifp;
406 im6o.im6o_multicast_hlim = 255;
407 im6o.im6o_multicast_loop = 0;
408 }
409
410 icmp6len = sizeof(*nd_ns);
411 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len;
412 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
413
414 /* fill neighbor solicitation packet */
415 ip6 = mtod(m, struct ip6_hdr *);
416 ip6->ip6_flow = 0;
417 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
418 ip6->ip6_vfc |= IPV6_VERSION;
419 /* ip6->ip6_plen will be set later */
420 ip6->ip6_nxt = IPPROTO_ICMPV6;
421 ip6->ip6_hlim = 255;
422 if (daddr6)
423 ip6->ip6_dst = *daddr6;
424 else {
425 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
426 ip6->ip6_dst.s6_addr16[1] = 0;
427 ip6->ip6_dst.s6_addr32[1] = 0;
428 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE;
429 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3];
430 ip6->ip6_dst.s6_addr8[12] = 0xff;
431 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0)
432 goto bad;
433 }
434 if (!dad) {
435 /*
436 * RFC2461 7.2.2:
437 * "If the source address of the packet prompting the
438 * solicitation is the same as one of the addresses assigned
439 * to the outgoing interface, that address SHOULD be placed
440 * in the IP Source Address of the outgoing solicitation.
441 * Otherwise, any one of the addresses assigned to the
442 * interface should be used."
443 *
444 * We use the source address for the prompting packet
445 * (saddr6), if:
446 * - saddr6 is given from the caller (by giving "ln"), and
447 * - saddr6 belongs to the outgoing interface.
448 * Otherwise, we perform the source address selection as usual.
449 */
450 struct ip6_hdr *hip6; /* hold ip6 */
451 struct in6_addr *hsrc = NULL;
452
453 if (ln && ln->ln_hold) {
454 /*
455 * assuming every packet in ln_hold has the same IP
456 * header
457 */
458 hip6 = mtod(ln->ln_hold, struct ip6_hdr *);
459 /* XXX pullup? */
460 if (sizeof(*hip6) < ln->ln_hold->m_len)
461 hsrc = &hip6->ip6_src;
462 else
463 hsrc = NULL;
464 }
465 if (hsrc && in6ifa_ifpwithaddr(ifp, hsrc))
466 src = hsrc;
467 else {
468 int error;
469 struct sockaddr_in6 dst_sa;
470
471 bzero(&dst_sa, sizeof(dst_sa));
472 dst_sa.sin6_family = AF_INET6;
473 dst_sa.sin6_len = sizeof(dst_sa);
474 dst_sa.sin6_addr = ip6->ip6_dst;
475
476 src = in6_selectsrc(&dst_sa, NULL,
477 NULL, &ro, NULL, NULL, &error);
478 if (src == NULL) {
479 char ip6buf[INET6_ADDRSTRLEN];
480 nd6log((LOG_DEBUG,
481 "nd6_ns_output: source can't be "
482 "determined: dst=%s, error=%d\n",
483 ip6_sprintf(ip6buf, &dst_sa.sin6_addr),
484 error));
485 goto bad;
486 }
487 }
488 } else {
489 /*
490 * Source address for DAD packet must always be IPv6
491 * unspecified address. (0::0)
492 * We actually don't have to 0-clear the address (we did it
493 * above), but we do so here explicitly to make the intention
494 * clearer.
495 */
496 bzero(&src_in, sizeof(src_in));
497 src = &src_in;
498 }
499 ip6->ip6_src = *src;
500 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1);
501 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT;
502 nd_ns->nd_ns_code = 0;
503 nd_ns->nd_ns_reserved = 0;
504 nd_ns->nd_ns_target = *taddr6;
505 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */
506
507 /*
508 * Add source link-layer address option.
509 *
510 * spec implementation
511 * --- ---
512 * DAD packet MUST NOT do not add the option
513 * there's no link layer address:
514 * impossible do not add the option
515 * there's link layer address:
516 * Multicast NS MUST add one add the option
517 * Unicast NS SHOULD add one add the option
518 */
519 if (!dad && (mac = nd6_ifptomac(ifp))) {
520 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
521 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
522 /* 8 byte alignments... */
523 optlen = (optlen + 7) & ~7;
524
525 m->m_pkthdr.len += optlen;
526 m->m_len += optlen;
527 icmp6len += optlen;
528 bzero((caddr_t)nd_opt, optlen);
529 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR;
530 nd_opt->nd_opt_len = optlen >> 3;
531 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
532 }
533
534 ip6->ip6_plen = htons((u_short)icmp6len);
535 nd_ns->nd_ns_cksum = 0;
536 nd_ns->nd_ns_cksum =
537 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len);
538
539 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL);
540 icmp6_ifstat_inc(ifp, ifs6_out_msg);
541 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit);
542 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++;
543
544 if (ro.ro_rt) { /* we don't cache this route. */
545 RTFREE(ro.ro_rt);
546 }
547 return;
548
549 bad:
550 if (ro.ro_rt) {
551 RTFREE(ro.ro_rt);
552 }
553 m_freem(m);
554 return;
555 }
556
557 /*
558 * Neighbor advertisement input handling.
559 *
560 * Based on RFC 2461
561 * Based on RFC 2462 (duplicate address detection)
562 *
563 * the following items are not implemented yet:
564 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
565 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
566 */
567 void
568 nd6_na_input(struct mbuf *m, int off, int icmp6len)
569 {
570 struct ifnet *ifp = m->m_pkthdr.rcvif;
571 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
572 struct nd_neighbor_advert *nd_na;
573 struct in6_addr daddr6 = ip6->ip6_dst;
574 struct in6_addr taddr6;
575 int flags;
576 int is_router;
577 int is_solicited;
578 int is_override;
579 char *lladdr = NULL;
580 int lladdrlen = 0;
581 struct ifaddr *ifa;
582 struct llinfo_nd6 *ln;
583 struct rtentry *rt;
584 struct sockaddr_dl *sdl;
585 union nd_opts ndopts;
586 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
587
588 if (ip6->ip6_hlim != 255) {
589 nd6log((LOG_ERR,
590 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n",
591 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
592 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
593 goto bad;
594 }
595
596 #ifndef PULLDOWN_TEST
597 IP6_EXTHDR_CHECK(m, off, icmp6len,);
598 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off);
599 #else
600 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len);
601 if (nd_na == NULL) {
602 icmp6stat.icp6s_tooshort++;
603 return;
604 }
605 #endif
606
607 flags = nd_na->nd_na_flags_reserved;
608 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0);
609 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0);
610 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0);
611
612 taddr6 = nd_na->nd_na_target;
613 if (in6_setscope(&taddr6, ifp, NULL))
614 goto bad; /* XXX: impossible */
615
616 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
617 nd6log((LOG_ERR,
618 "nd6_na_input: invalid target address %s\n",
619 ip6_sprintf(ip6bufs, &taddr6)));
620 goto bad;
621 }
622 if (IN6_IS_ADDR_MULTICAST(&daddr6))
623 if (is_solicited) {
624 nd6log((LOG_ERR,
625 "nd6_na_input: a solicited adv is multicasted\n"));
626 goto bad;
627 }
628
629 icmp6len -= sizeof(*nd_na);
630 nd6_option_init(nd_na + 1, icmp6len, &ndopts);
631 if (nd6_options(&ndopts) < 0) {
632 nd6log((LOG_INFO,
633 "nd6_na_input: invalid ND option, ignored\n"));
634 /* nd6_options have incremented stats */
635 goto freeit;
636 }
637
638 if (ndopts.nd_opts_tgt_lladdr) {
639 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
640 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
641 }
642
643 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
644
645 /*
646 * Target address matches one of my interface address.
647 *
648 * If my address is tentative, this means that there's somebody
649 * already using the same address as mine. This indicates DAD failure.
650 * This is defined in RFC 2462.
651 *
652 * Otherwise, process as defined in RFC 2461.
653 */
654 if (ifa
655 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) {
656 nd6_dad_na_input(ifa);
657 goto freeit;
658 }
659
660 /* Just for safety, maybe unnecessary. */
661 if (ifa) {
662 log(LOG_ERR,
663 "nd6_na_input: duplicate IP6 address %s\n",
664 ip6_sprintf(ip6bufs, &taddr6));
665 goto freeit;
666 }
667
668 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
669 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s "
670 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6),
671 ifp->if_addrlen, lladdrlen - 2));
672 goto bad;
673 }
674
675 /*
676 * If no neighbor cache entry is found, NA SHOULD silently be
677 * discarded.
678 */
679 rt = nd6_lookup(&taddr6, 0, ifp);
680 if ((rt == NULL) ||
681 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) ||
682 ((sdl = SDL(rt->rt_gateway)) == NULL))
683 goto freeit;
684
685 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
686 /*
687 * If the link-layer has address, and no lladdr option came,
688 * discard the packet.
689 */
690 if (ifp->if_addrlen && lladdr == NULL)
691 goto freeit;
692
693 /*
694 * Record link-layer address, and update the state.
695 */
696 sdl->sdl_alen = ifp->if_addrlen;
697 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
698 if (is_solicited) {
699 ln->ln_state = ND6_LLINFO_REACHABLE;
700 ln->ln_byhint = 0;
701 if (!ND6_LLINFO_PERMANENT(ln)) {
702 nd6_llinfo_settimer(ln,
703 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz);
704 }
705 } else {
706 ln->ln_state = ND6_LLINFO_STALE;
707 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz);
708 }
709 if ((ln->ln_router = is_router) != 0) {
710 /*
711 * This means a router's state has changed from
712 * non-reachable to probably reachable, and might
713 * affect the status of associated prefixes..
714 */
715 pfxlist_onlink_check();
716 }
717 } else {
718 int llchange;
719
720 /*
721 * Check if the link-layer address has changed or not.
722 */
723 if (lladdr == NULL)
724 llchange = 0;
725 else {
726 if (sdl->sdl_alen) {
727 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen))
728 llchange = 1;
729 else
730 llchange = 0;
731 } else
732 llchange = 1;
733 }
734
735 /*
736 * This is VERY complex. Look at it with care.
737 *
738 * override solicit lladdr llchange action
739 * (L: record lladdr)
740 *
741 * 0 0 n -- (2c)
742 * 0 0 y n (2b) L
743 * 0 0 y y (1) REACHABLE->STALE
744 * 0 1 n -- (2c) *->REACHABLE
745 * 0 1 y n (2b) L *->REACHABLE
746 * 0 1 y y (1) REACHABLE->STALE
747 * 1 0 n -- (2a)
748 * 1 0 y n (2a) L
749 * 1 0 y y (2a) L *->STALE
750 * 1 1 n -- (2a) *->REACHABLE
751 * 1 1 y n (2a) L *->REACHABLE
752 * 1 1 y y (2a) L *->REACHABLE
753 */
754 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */
755 /*
756 * If state is REACHABLE, make it STALE.
757 * no other updates should be done.
758 */
759 if (ln->ln_state == ND6_LLINFO_REACHABLE) {
760 ln->ln_state = ND6_LLINFO_STALE;
761 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz);
762 }
763 goto freeit;
764 } else if (is_override /* (2a) */
765 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */
766 || lladdr == NULL) { /* (2c) */
767 /*
768 * Update link-local address, if any.
769 */
770 if (lladdr != NULL) {
771 sdl->sdl_alen = ifp->if_addrlen;
772 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
773 }
774
775 /*
776 * If solicited, make the state REACHABLE.
777 * If not solicited and the link-layer address was
778 * changed, make it STALE.
779 */
780 if (is_solicited) {
781 ln->ln_state = ND6_LLINFO_REACHABLE;
782 ln->ln_byhint = 0;
783 if (!ND6_LLINFO_PERMANENT(ln)) {
784 nd6_llinfo_settimer(ln,
785 (long)ND_IFINFO(ifp)->reachable * hz);
786 }
787 } else {
788 if (lladdr != NULL && llchange) {
789 ln->ln_state = ND6_LLINFO_STALE;
790 nd6_llinfo_settimer(ln,
791 (long)nd6_gctimer * hz);
792 }
793 }
794 }
795
796 if (ln->ln_router && !is_router) {
797 /*
798 * The peer dropped the router flag.
799 * Remove the sender from the Default Router List and
800 * update the Destination Cache entries.
801 */
802 struct nd_defrouter *dr;
803 struct in6_addr *in6;
804 int s;
805
806 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr;
807
808 /*
809 * Lock to protect the default router list.
810 * XXX: this might be unnecessary, since this function
811 * is only called under the network software interrupt
812 * context. However, we keep it just for safety.
813 */
814 s = splnet();
815 dr = defrouter_lookup(in6, ifp);
816 if (dr)
817 defrtrlist_del(dr);
818 else if (!ip6_forwarding) {
819 /*
820 * Even if the neighbor is not in the default
821 * router list, the neighbor may be used
822 * as a next hop for some destinations
823 * (e.g. redirect case). So we must
824 * call rt6_flush explicitly.
825 */
826 rt6_flush(&ip6->ip6_src, ifp);
827 }
828 splx(s);
829 }
830 ln->ln_router = is_router;
831 }
832 rt->rt_flags &= ~RTF_REJECT;
833 ln->ln_asked = 0;
834 if (ln->ln_hold) {
835 struct mbuf *m_hold, *m_hold_next;
836
837 /*
838 * reset the ln_hold in advance, to explicitly
839 * prevent a ln_hold lookup in nd6_output()
840 * (wouldn't happen, though...)
841 */
842 for (m_hold = ln->ln_hold;
843 m_hold; m_hold = m_hold_next) {
844 m_hold_next = m_hold->m_nextpkt;
845 m_hold->m_nextpkt = NULL;
846 /*
847 * we assume ifp is not a loopback here, so just set
848 * the 2nd argument as the 1st one.
849 */
850 nd6_output(ifp, ifp, m_hold,
851 (struct sockaddr_in6 *)rt_key(rt), rt);
852 }
853 ln->ln_hold = NULL;
854 }
855
856 freeit:
857 m_freem(m);
858 return;
859
860 bad:
861 icmp6stat.icp6s_badna++;
862 m_freem(m);
863 }
864
865 /*
866 * Neighbor advertisement output handling.
867 *
868 * Based on RFC 2461
869 *
870 * the following items are not implemented yet:
871 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
872 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
873 *
874 * tlladdr - 1 if include target link-layer address
875 * sdl0 - sockaddr_dl (= proxy NA) or NULL
876 */
877 void
878 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0,
879 const struct in6_addr *taddr6, u_long flags, int tlladdr,
880 struct sockaddr *sdl0)
881 {
882 struct mbuf *m;
883 struct ip6_hdr *ip6;
884 struct nd_neighbor_advert *nd_na;
885 struct ip6_moptions im6o;
886 struct in6_addr *src, daddr6;
887 struct sockaddr_in6 dst_sa;
888 int icmp6len, maxlen, error;
889 caddr_t mac = NULL;
890 struct route_in6 ro;
891
892 bzero(&ro, sizeof(ro));
893
894 daddr6 = *daddr6_0; /* make a local copy for modification */
895
896 /* estimate the size of message */
897 maxlen = sizeof(*ip6) + sizeof(*nd_na);
898 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
899 if (max_linkhdr + maxlen >= MCLBYTES) {
900 #ifdef DIAGNOSTIC
901 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES "
902 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
903 #endif
904 return;
905 }
906
907 MGETHDR(m, M_DONTWAIT, MT_DATA);
908 if (m && max_linkhdr + maxlen >= MHLEN) {
909 MCLGET(m, M_DONTWAIT);
910 if ((m->m_flags & M_EXT) == 0) {
911 m_free(m);
912 m = NULL;
913 }
914 }
915 if (m == NULL)
916 return;
917 m->m_pkthdr.rcvif = NULL;
918
919 if (IN6_IS_ADDR_MULTICAST(&daddr6)) {
920 m->m_flags |= M_MCAST;
921 im6o.im6o_multicast_ifp = ifp;
922 im6o.im6o_multicast_hlim = 255;
923 im6o.im6o_multicast_loop = 0;
924 }
925
926 icmp6len = sizeof(*nd_na);
927 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len;
928 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
929
930 /* fill neighbor advertisement packet */
931 ip6 = mtod(m, struct ip6_hdr *);
932 ip6->ip6_flow = 0;
933 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
934 ip6->ip6_vfc |= IPV6_VERSION;
935 ip6->ip6_nxt = IPPROTO_ICMPV6;
936 ip6->ip6_hlim = 255;
937 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) {
938 /* reply to DAD */
939 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
940 daddr6.s6_addr16[1] = 0;
941 daddr6.s6_addr32[1] = 0;
942 daddr6.s6_addr32[2] = 0;
943 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE;
944 if (in6_setscope(&daddr6, ifp, NULL))
945 goto bad;
946
947 flags &= ~ND_NA_FLAG_SOLICITED;
948 }
949 ip6->ip6_dst = daddr6;
950 bzero(&dst_sa, sizeof(struct sockaddr_in6));
951 dst_sa.sin6_family = AF_INET6;
952 dst_sa.sin6_len = sizeof(struct sockaddr_in6);
953 dst_sa.sin6_addr = daddr6;
954
955 /*
956 * Select a source whose scope is the same as that of the dest.
957 */
958 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa));
959 src = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &error);
960 if (src == NULL) {
961 char ip6buf[INET6_ADDRSTRLEN];
962 nd6log((LOG_DEBUG, "nd6_na_output: source can't be "
963 "determined: dst=%s, error=%d\n",
964 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error));
965 goto bad;
966 }
967 ip6->ip6_src = *src;
968 nd_na = (struct nd_neighbor_advert *)(ip6 + 1);
969 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT;
970 nd_na->nd_na_code = 0;
971 nd_na->nd_na_target = *taddr6;
972 in6_clearscope(&nd_na->nd_na_target); /* XXX */
973
974 /*
975 * "tlladdr" indicates NS's condition for adding tlladdr or not.
976 * see nd6_ns_input() for details.
977 * Basically, if NS packet is sent to unicast/anycast addr,
978 * target lladdr option SHOULD NOT be included.
979 */
980 if (tlladdr) {
981 /*
982 * sdl0 != NULL indicates proxy NA. If we do proxy, use
983 * lladdr in sdl0. If we are not proxying (sending NA for
984 * my address) use lladdr configured for the interface.
985 */
986 if (sdl0 == NULL) {
987 #ifdef DEV_CARP
988 if (ifp->if_carp)
989 mac = carp_macmatch6(ifp->if_carp, m, taddr6);
990 if (mac == NULL)
991 mac = nd6_ifptomac(ifp);
992 #else
993 mac = nd6_ifptomac(ifp);
994 #endif
995 } else if (sdl0->sa_family == AF_LINK) {
996 struct sockaddr_dl *sdl;
997 sdl = (struct sockaddr_dl *)sdl0;
998 if (sdl->sdl_alen == ifp->if_addrlen)
999 mac = LLADDR(sdl);
1000 }
1001 }
1002 if (tlladdr && mac) {
1003 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
1004 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1);
1005
1006 /* roundup to 8 bytes alignment! */
1007 optlen = (optlen + 7) & ~7;
1008
1009 m->m_pkthdr.len += optlen;
1010 m->m_len += optlen;
1011 icmp6len += optlen;
1012 bzero((caddr_t)nd_opt, optlen);
1013 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
1014 nd_opt->nd_opt_len = optlen >> 3;
1015 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
1016 } else
1017 flags &= ~ND_NA_FLAG_OVERRIDE;
1018
1019 ip6->ip6_plen = htons((u_short)icmp6len);
1020 nd_na->nd_na_flags_reserved = flags;
1021 nd_na->nd_na_cksum = 0;
1022 nd_na->nd_na_cksum =
1023 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len);
1024
1025 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL);
1026 icmp6_ifstat_inc(ifp, ifs6_out_msg);
1027 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert);
1028 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++;
1029
1030 if (ro.ro_rt) { /* we don't cache this route. */
1031 RTFREE(ro.ro_rt);
1032 }
1033 return;
1034
1035 bad:
1036 if (ro.ro_rt) {
1037 RTFREE(ro.ro_rt);
1038 }
1039 m_freem(m);
1040 return;
1041 }
1042
1043 caddr_t
1044 nd6_ifptomac(struct ifnet *ifp)
1045 {
1046 switch (ifp->if_type) {
1047 case IFT_ARCNET:
1048 case IFT_ETHER:
1049 case IFT_FDDI:
1050 case IFT_IEEE1394:
1051 #ifdef IFT_L2VLAN
1052 case IFT_L2VLAN:
1053 #endif
1054 #ifdef IFT_IEEE80211
1055 case IFT_IEEE80211:
1056 #endif
1057 #ifdef IFT_CARP
1058 case IFT_CARP:
1059 #endif
1060 case IFT_BRIDGE:
1061 case IFT_ISO88025:
1062 return IF_LLADDR(ifp);
1063 default:
1064 return NULL;
1065 }
1066 }
1067
1068 TAILQ_HEAD(dadq_head, dadq);
1069 struct dadq {
1070 TAILQ_ENTRY(dadq) dad_list;
1071 struct ifaddr *dad_ifa;
1072 int dad_count; /* max NS to send */
1073 int dad_ns_tcount; /* # of trials to send NS */
1074 int dad_ns_ocount; /* NS sent so far */
1075 int dad_ns_icount;
1076 int dad_na_icount;
1077 struct callout dad_timer_ch;
1078 };
1079
1080 static struct dadq_head dadq;
1081 static int dad_init = 0;
1082
1083 static struct dadq *
1084 nd6_dad_find(struct ifaddr *ifa)
1085 {
1086 struct dadq *dp;
1087
1088 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) {
1089 if (dp->dad_ifa == ifa)
1090 return dp;
1091 }
1092 return NULL;
1093 }
1094
1095 static void
1096 nd6_dad_starttimer(struct dadq *dp, int ticks)
1097 {
1098
1099 callout_reset(&dp->dad_timer_ch, ticks,
1100 (void (*)(void *))nd6_dad_timer, (void *)dp->dad_ifa);
1101 }
1102
1103 static void
1104 nd6_dad_stoptimer(struct dadq *dp)
1105 {
1106
1107 callout_stop(&dp->dad_timer_ch);
1108 }
1109
1110 /*
1111 * Start Duplicate Address Detection (DAD) for specified interface address.
1112 */
1113 void
1114 nd6_dad_start(struct ifaddr *ifa, int delay)
1115 {
1116 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1117 struct dadq *dp;
1118 char ip6buf[INET6_ADDRSTRLEN];
1119
1120 if (!dad_init) {
1121 TAILQ_INIT(&dadq);
1122 dad_init++;
1123 }
1124
1125 /*
1126 * If we don't need DAD, don't do it.
1127 * There are several cases:
1128 * - DAD is disabled (ip6_dad_count == 0)
1129 * - the interface address is anycast
1130 */
1131 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
1132 log(LOG_DEBUG,
1133 "nd6_dad_start: called with non-tentative address "
1134 "%s(%s)\n",
1135 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1136 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1137 return;
1138 }
1139 if (ia->ia6_flags & IN6_IFF_ANYCAST) {
1140 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1141 return;
1142 }
1143 if (!ip6_dad_count) {
1144 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1145 return;
1146 }
1147 if (ifa->ifa_ifp == NULL)
1148 panic("nd6_dad_start: ifa->ifa_ifp == NULL");
1149 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) {
1150 return;
1151 }
1152 if (nd6_dad_find(ifa) != NULL) {
1153 /* DAD already in progress */
1154 return;
1155 }
1156
1157 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT);
1158 if (dp == NULL) {
1159 log(LOG_ERR, "nd6_dad_start: memory allocation failed for "
1160 "%s(%s)\n",
1161 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1162 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1163 return;
1164 }
1165 bzero(dp, sizeof(*dp));
1166 callout_init(&dp->dad_timer_ch, 0);
1167 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list);
1168
1169 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp),
1170 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1171
1172 /*
1173 * Send NS packet for DAD, ip6_dad_count times.
1174 * Note that we must delay the first transmission, if this is the
1175 * first packet to be sent from the interface after interface
1176 * (re)initialization.
1177 */
1178 dp->dad_ifa = ifa;
1179 IFAREF(ifa); /* just for safety */
1180 dp->dad_count = ip6_dad_count;
1181 dp->dad_ns_icount = dp->dad_na_icount = 0;
1182 dp->dad_ns_ocount = dp->dad_ns_tcount = 0;
1183 if (delay == 0) {
1184 nd6_dad_ns_output(dp, ifa);
1185 nd6_dad_starttimer(dp,
1186 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1187 } else {
1188 nd6_dad_starttimer(dp, delay);
1189 }
1190 }
1191
1192 /*
1193 * terminate DAD unconditionally. used for address removals.
1194 */
1195 void
1196 nd6_dad_stop(struct ifaddr *ifa)
1197 {
1198 struct dadq *dp;
1199
1200 if (!dad_init)
1201 return;
1202 dp = nd6_dad_find(ifa);
1203 if (!dp) {
1204 /* DAD wasn't started yet */
1205 return;
1206 }
1207
1208 nd6_dad_stoptimer(dp);
1209
1210 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1211 free(dp, M_IP6NDP);
1212 dp = NULL;
1213 IFAFREE(ifa);
1214 }
1215
1216 static void
1217 nd6_dad_timer(struct ifaddr *ifa)
1218 {
1219 int s;
1220 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1221 struct dadq *dp;
1222 char ip6buf[INET6_ADDRSTRLEN];
1223
1224 s = splnet(); /* XXX */
1225
1226 /* Sanity check */
1227 if (ia == NULL) {
1228 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n");
1229 goto done;
1230 }
1231 dp = nd6_dad_find(ifa);
1232 if (dp == NULL) {
1233 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n");
1234 goto done;
1235 }
1236 if (ia->ia6_flags & IN6_IFF_DUPLICATED) {
1237 log(LOG_ERR, "nd6_dad_timer: called with duplicated address "
1238 "%s(%s)\n",
1239 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1240 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1241 goto done;
1242 }
1243 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) {
1244 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address "
1245 "%s(%s)\n",
1246 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1247 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1248 goto done;
1249 }
1250
1251 /* timeouted with IFF_{RUNNING,UP} check */
1252 if (dp->dad_ns_tcount > dad_maxtry) {
1253 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n",
1254 if_name(ifa->ifa_ifp)));
1255
1256 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1257 free(dp, M_IP6NDP);
1258 dp = NULL;
1259 IFAFREE(ifa);
1260 goto done;
1261 }
1262
1263 /* Need more checks? */
1264 if (dp->dad_ns_ocount < dp->dad_count) {
1265 /*
1266 * We have more NS to go. Send NS packet for DAD.
1267 */
1268 nd6_dad_ns_output(dp, ifa);
1269 nd6_dad_starttimer(dp,
1270 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1271 } else {
1272 /*
1273 * We have transmitted sufficient number of DAD packets.
1274 * See what we've got.
1275 */
1276 int duplicate;
1277
1278 duplicate = 0;
1279
1280 if (dp->dad_na_icount) {
1281 /*
1282 * the check is in nd6_dad_na_input(),
1283 * but just in case
1284 */
1285 duplicate++;
1286 }
1287
1288 if (dp->dad_ns_icount) {
1289 /* We've seen NS, means DAD has failed. */
1290 duplicate++;
1291 }
1292
1293 if (duplicate) {
1294 /* (*dp) will be freed in nd6_dad_duplicated() */
1295 dp = NULL;
1296 nd6_dad_duplicated(ifa);
1297 } else {
1298 /*
1299 * We are done with DAD. No NA came, no NS came.
1300 * No duplicate address found.
1301 */
1302 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1303
1304 nd6log((LOG_DEBUG,
1305 "%s: DAD complete for %s - no duplicates found\n",
1306 if_name(ifa->ifa_ifp),
1307 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1308
1309 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1310 free(dp, M_IP6NDP);
1311 dp = NULL;
1312 IFAFREE(ifa);
1313 }
1314 }
1315
1316 done:
1317 splx(s);
1318 }
1319
1320 void
1321 nd6_dad_duplicated(struct ifaddr *ifa)
1322 {
1323 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1324 struct ifnet *ifp;
1325 struct dadq *dp;
1326 char ip6buf[INET6_ADDRSTRLEN];
1327
1328 dp = nd6_dad_find(ifa);
1329 if (dp == NULL) {
1330 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n");
1331 return;
1332 }
1333
1334 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: "
1335 "NS in/out=%d/%d, NA in=%d\n",
1336 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1337 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount);
1338
1339 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1340 ia->ia6_flags |= IN6_IFF_DUPLICATED;
1341
1342 /* We are done with DAD, with duplicate address found. (failure) */
1343 nd6_dad_stoptimer(dp);
1344
1345 ifp = ifa->ifa_ifp;
1346 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n",
1347 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr));
1348 log(LOG_ERR, "%s: manual intervention required\n",
1349 if_name(ifp));
1350
1351 /*
1352 * If the address is a link-local address formed from an interface
1353 * identifier based on the hardware address which is supposed to be
1354 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP
1355 * operation on the interface SHOULD be disabled.
1356 * [rfc2462bis-03 Section 5.4.5]
1357 */
1358 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) {
1359 struct in6_addr in6;
1360
1361 /*
1362 * To avoid over-reaction, we only apply this logic when we are
1363 * very sure that hardware addresses are supposed to be unique.
1364 */
1365 switch (ifp->if_type) {
1366 case IFT_ETHER:
1367 case IFT_FDDI:
1368 case IFT_ATM:
1369 case IFT_IEEE1394:
1370 #ifdef IFT_IEEE80211
1371 case IFT_IEEE80211:
1372 #endif
1373 in6 = ia->ia_addr.sin6_addr;
1374 if (in6_get_hw_ifid(ifp, &in6) == 0 &&
1375 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) {
1376 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED;
1377 log(LOG_ERR, "%s: possible hardware address "
1378 "duplication detected, disable IPv6\n",
1379 if_name(ifp));
1380 }
1381 break;
1382 }
1383 }
1384
1385 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1386 free(dp, M_IP6NDP);
1387 dp = NULL;
1388 IFAFREE(ifa);
1389 }
1390
1391 static void
1392 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa)
1393 {
1394 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1395 struct ifnet *ifp = ifa->ifa_ifp;
1396
1397 dp->dad_ns_tcount++;
1398 if ((ifp->if_flags & IFF_UP) == 0) {
1399 return;
1400 }
1401 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
1402 return;
1403 }
1404
1405 dp->dad_ns_ocount++;
1406 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1);
1407 }
1408
1409 static void
1410 nd6_dad_ns_input(struct ifaddr *ifa)
1411 {
1412 struct in6_ifaddr *ia;
1413 struct ifnet *ifp;
1414 const struct in6_addr *taddr6;
1415 struct dadq *dp;
1416 int duplicate;
1417
1418 if (ifa == NULL)
1419 panic("ifa == NULL in nd6_dad_ns_input");
1420
1421 ia = (struct in6_ifaddr *)ifa;
1422 ifp = ifa->ifa_ifp;
1423 taddr6 = &ia->ia_addr.sin6_addr;
1424 duplicate = 0;
1425 dp = nd6_dad_find(ifa);
1426
1427 /* Quickhack - completely ignore DAD NS packets */
1428 if (dad_ignore_ns) {
1429 char ip6buf[INET6_ADDRSTRLEN];
1430 nd6log((LOG_INFO,
1431 "nd6_dad_ns_input: ignoring DAD NS packet for "
1432 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6),
1433 if_name(ifa->ifa_ifp)));
1434 return;
1435 }
1436
1437 /*
1438 * if I'm yet to start DAD, someone else started using this address
1439 * first. I have a duplicate and you win.
1440 */
1441 if (dp == NULL || dp->dad_ns_ocount == 0)
1442 duplicate++;
1443
1444 /* XXX more checks for loopback situation - see nd6_dad_timer too */
1445
1446 if (duplicate) {
1447 dp = NULL; /* will be freed in nd6_dad_duplicated() */
1448 nd6_dad_duplicated(ifa);
1449 } else {
1450 /*
1451 * not sure if I got a duplicate.
1452 * increment ns count and see what happens.
1453 */
1454 if (dp)
1455 dp->dad_ns_icount++;
1456 }
1457 }
1458
1459 static void
1460 nd6_dad_na_input(struct ifaddr *ifa)
1461 {
1462 struct dadq *dp;
1463
1464 if (ifa == NULL)
1465 panic("ifa == NULL in nd6_dad_na_input");
1466
1467 dp = nd6_dad_find(ifa);
1468 if (dp)
1469 dp->dad_na_icount++;
1470
1471 /* remove the address. */
1472 nd6_dad_duplicated(ifa);
1473 }
Cache object: 97a6ac669a43557ac05f5886e40597ee
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