1 /* $FreeBSD$ */
2 /* $KAME: nd6_nbr.c,v 1.86 2002/01/21 02:33:04 jinmei Exp $ */
3
4 /*-
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 #include "opt_inet.h"
34 #include "opt_inet6.h"
35 #include "opt_ipsec.h"
36 #include "opt_carp.h"
37
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/malloc.h>
41 #include <sys/mbuf.h>
42 #include <sys/socket.h>
43 #include <sys/sockio.h>
44 #include <sys/time.h>
45 #include <sys/kernel.h>
46 #include <sys/errno.h>
47 #include <sys/syslog.h>
48 #include <sys/queue.h>
49 #include <sys/callout.h>
50
51 #include <net/if.h>
52 #include <net/if_types.h>
53 #include <net/if_dl.h>
54 #include <net/if_var.h>
55 #include <net/route.h>
56
57 #include <netinet/in.h>
58 #include <netinet/in_var.h>
59 #include <netinet6/in6_var.h>
60 #include <netinet6/in6_ifattach.h>
61 #include <netinet/ip6.h>
62 #include <netinet6/ip6_var.h>
63 #include <netinet6/scope6_var.h>
64 #include <netinet6/nd6.h>
65 #include <netinet/icmp6.h>
66
67 #ifdef DEV_CARP
68 #include <netinet/ip_carp.h>
69 #endif
70
71 #define SDL(s) ((struct sockaddr_dl *)s)
72
73 struct dadq;
74 static struct dadq *nd6_dad_find __P((struct ifaddr *));
75 static void nd6_dad_starttimer __P((struct dadq *, int));
76 static void nd6_dad_stoptimer __P((struct dadq *));
77 static void nd6_dad_timer __P((struct ifaddr *));
78 static void nd6_dad_ns_output __P((struct dadq *, struct ifaddr *));
79 static void nd6_dad_ns_input __P((struct ifaddr *));
80 static void nd6_dad_na_input __P((struct ifaddr *));
81
82 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/
83 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */
84
85 /*
86 * Input a Neighbor Solicitation Message.
87 *
88 * Based on RFC 2461
89 * Based on RFC 2462 (duplicate address detection)
90 */
91 void
92 nd6_ns_input(struct mbuf *m, int off, int icmp6len)
93 {
94 struct ifnet *ifp = m->m_pkthdr.rcvif;
95 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
96 struct nd_neighbor_solicit *nd_ns;
97 struct in6_addr saddr6 = ip6->ip6_src;
98 struct in6_addr daddr6 = ip6->ip6_dst;
99 struct in6_addr taddr6;
100 struct in6_addr myaddr6;
101 char *lladdr = NULL;
102 struct ifaddr *ifa = NULL;
103 int lladdrlen = 0;
104 int anycast = 0, proxy = 0, tentative = 0;
105 int tlladdr;
106 union nd_opts ndopts;
107 struct sockaddr_dl *proxydl = NULL;
108 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
109
110 #ifndef PULLDOWN_TEST
111 IP6_EXTHDR_CHECK(m, off, icmp6len,);
112 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off);
113 #else
114 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len);
115 if (nd_ns == NULL) {
116 icmp6stat.icp6s_tooshort++;
117 return;
118 }
119 #endif
120 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */
121 taddr6 = nd_ns->nd_ns_target;
122 if (in6_setscope(&taddr6, ifp, NULL) != 0)
123 goto bad;
124
125 if (ip6->ip6_hlim != 255) {
126 nd6log((LOG_ERR,
127 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n",
128 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
129 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
130 goto bad;
131 }
132
133 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
134 /* dst has to be a solicited node multicast address. */
135 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL &&
136 /* don't check ifindex portion */
137 daddr6.s6_addr32[1] == 0 &&
138 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE &&
139 daddr6.s6_addr8[12] == 0xff) {
140 ; /* good */
141 } else {
142 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
143 "(wrong ip6 dst)\n"));
144 goto bad;
145 }
146 } else if (!nd6_onlink_ns_rfc4861) {
147 struct sockaddr_in6 src_sa6;
148
149 /*
150 * According to recent IETF discussions, it is not a good idea
151 * to accept a NS from an address which would not be deemed
152 * to be a neighbor otherwise. This point is expected to be
153 * clarified in future revisions of the specification.
154 */
155 bzero(&src_sa6, sizeof(src_sa6));
156 src_sa6.sin6_family = AF_INET6;
157 src_sa6.sin6_len = sizeof(src_sa6);
158 src_sa6.sin6_addr = saddr6;
159 if (!nd6_is_addr_neighbor(&src_sa6, ifp)) {
160 nd6log((LOG_INFO, "nd6_ns_input: "
161 "NS packet from non-neighbor\n"));
162 goto bad;
163 }
164 }
165
166 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
167 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n"));
168 goto bad;
169 }
170
171 icmp6len -= sizeof(*nd_ns);
172 nd6_option_init(nd_ns + 1, icmp6len, &ndopts);
173 if (nd6_options(&ndopts) < 0) {
174 nd6log((LOG_INFO,
175 "nd6_ns_input: invalid ND option, ignored\n"));
176 /* nd6_options have incremented stats */
177 goto freeit;
178 }
179
180 if (ndopts.nd_opts_src_lladdr) {
181 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
182 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
183 }
184
185 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) {
186 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
187 "(link-layer address option)\n"));
188 goto bad;
189 }
190
191 /*
192 * Attaching target link-layer address to the NA?
193 * (RFC 2461 7.2.4)
194 *
195 * NS IP dst is unicast/anycast MUST NOT add
196 * NS IP dst is solicited-node multicast MUST add
197 *
198 * In implementation, we add target link-layer address by default.
199 * We do not add one in MUST NOT cases.
200 */
201 if (!IN6_IS_ADDR_MULTICAST(&daddr6))
202 tlladdr = 0;
203 else
204 tlladdr = 1;
205
206 /*
207 * Target address (taddr6) must be either:
208 * (1) Valid unicast/anycast address for my receiving interface,
209 * (2) Unicast address for which I'm offering proxy service, or
210 * (3) "tentative" address on which DAD is being performed.
211 */
212 /* (1) and (3) check. */
213 #ifdef DEV_CARP
214 if (ifp->if_carp)
215 ifa = carp_iamatch6(ifp->if_carp, &taddr6);
216 if (ifa == NULL)
217 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
218 #else
219 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
220 #endif
221
222 /* (2) check. */
223 if (ifa == NULL) {
224 struct rtentry *rt;
225 struct sockaddr_in6 tsin6;
226 int need_proxy;
227
228 bzero(&tsin6, sizeof tsin6);
229 tsin6.sin6_len = sizeof(struct sockaddr_in6);
230 tsin6.sin6_family = AF_INET6;
231 tsin6.sin6_addr = taddr6;
232
233 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0);
234 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 &&
235 rt->rt_gateway->sa_family == AF_LINK);
236 if (rt)
237 rtfree(rt);
238 if (need_proxy) {
239 /*
240 * proxy NDP for single entry
241 */
242 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp,
243 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
244 if (ifa) {
245 proxy = 1;
246 proxydl = SDL(rt->rt_gateway);
247 }
248 }
249 }
250 if (ifa == NULL) {
251 /*
252 * We've got an NS packet, and we don't have that adddress
253 * assigned for us. We MUST silently ignore it.
254 * See RFC2461 7.2.3.
255 */
256 goto freeit;
257 }
258 myaddr6 = *IFA_IN6(ifa);
259 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST;
260 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE;
261 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED)
262 goto freeit;
263
264 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
265 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s "
266 "(if %d, NS packet %d)\n",
267 ip6_sprintf(ip6bufs, &taddr6),
268 ifp->if_addrlen, lladdrlen - 2));
269 goto bad;
270 }
271
272 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) {
273 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n",
274 ip6_sprintf(ip6bufs, &saddr6)));
275 goto freeit;
276 }
277
278 /*
279 * We have neighbor solicitation packet, with target address equals to
280 * one of my tentative address.
281 *
282 * src addr how to process?
283 * --- ---
284 * multicast of course, invalid (rejected in ip6_input)
285 * unicast somebody is doing address resolution -> ignore
286 * unspec dup address detection
287 *
288 * The processing is defined in RFC 2462.
289 */
290 if (tentative) {
291 /*
292 * If source address is unspecified address, it is for
293 * duplicate address detection.
294 *
295 * If not, the packet is for addess resolution;
296 * silently ignore it.
297 */
298 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6))
299 nd6_dad_ns_input(ifa);
300
301 goto freeit;
302 }
303
304 /*
305 * If the source address is unspecified address, entries must not
306 * be created or updated.
307 * It looks that sender is performing DAD. Output NA toward
308 * all-node multicast address, to tell the sender that I'm using
309 * the address.
310 * S bit ("solicited") must be zero.
311 */
312 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
313 struct in6_addr in6_all;
314
315 in6_all = in6addr_linklocal_allnodes;
316 if (in6_setscope(&in6_all, ifp, NULL) != 0)
317 goto bad;
318 nd6_na_output(ifp, &in6_all, &taddr6,
319 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
320 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0),
321 tlladdr, (struct sockaddr *)proxydl);
322 goto freeit;
323 }
324
325 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen,
326 ND_NEIGHBOR_SOLICIT, 0);
327
328 nd6_na_output(ifp, &saddr6, &taddr6,
329 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
330 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED,
331 tlladdr, (struct sockaddr *)proxydl);
332 freeit:
333 m_freem(m);
334 return;
335
336 bad:
337 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n",
338 ip6_sprintf(ip6bufs, &saddr6)));
339 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n",
340 ip6_sprintf(ip6bufs, &daddr6)));
341 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n",
342 ip6_sprintf(ip6bufs, &taddr6)));
343 icmp6stat.icp6s_badns++;
344 m_freem(m);
345 }
346
347 /*
348 * Output a Neighbor Solicitation Message. Caller specifies:
349 * - ICMP6 header source IP6 address
350 * - ND6 header target IP6 address
351 * - ND6 header source datalink address
352 *
353 * Based on RFC 2461
354 * Based on RFC 2462 (duplicate address detection)
355 *
356 * ln - for source address determination
357 * dad - duplicate address detection
358 */
359 void
360 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6,
361 const struct in6_addr *taddr6, struct llinfo_nd6 *ln, int dad)
362 {
363 struct mbuf *m;
364 struct ip6_hdr *ip6;
365 struct nd_neighbor_solicit *nd_ns;
366 struct in6_addr *src, src_in;
367 struct ip6_moptions im6o;
368 int icmp6len;
369 int maxlen;
370 caddr_t mac;
371 struct route_in6 ro;
372
373 bzero(&ro, sizeof(ro));
374
375 if (IN6_IS_ADDR_MULTICAST(taddr6))
376 return;
377
378 /* estimate the size of message */
379 maxlen = sizeof(*ip6) + sizeof(*nd_ns);
380 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
381 if (max_linkhdr + maxlen >= MCLBYTES) {
382 #ifdef DIAGNOSTIC
383 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES "
384 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
385 #endif
386 return;
387 }
388
389 MGETHDR(m, M_DONTWAIT, MT_DATA);
390 if (m && max_linkhdr + maxlen >= MHLEN) {
391 MCLGET(m, M_DONTWAIT);
392 if ((m->m_flags & M_EXT) == 0) {
393 m_free(m);
394 m = NULL;
395 }
396 }
397 if (m == NULL)
398 return;
399 m->m_pkthdr.rcvif = NULL;
400
401 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) {
402 m->m_flags |= M_MCAST;
403 im6o.im6o_multicast_ifp = ifp;
404 im6o.im6o_multicast_hlim = 255;
405 im6o.im6o_multicast_loop = 0;
406 }
407
408 icmp6len = sizeof(*nd_ns);
409 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len;
410 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
411
412 /* fill neighbor solicitation packet */
413 ip6 = mtod(m, struct ip6_hdr *);
414 ip6->ip6_flow = 0;
415 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
416 ip6->ip6_vfc |= IPV6_VERSION;
417 /* ip6->ip6_plen will be set later */
418 ip6->ip6_nxt = IPPROTO_ICMPV6;
419 ip6->ip6_hlim = 255;
420 if (daddr6)
421 ip6->ip6_dst = *daddr6;
422 else {
423 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
424 ip6->ip6_dst.s6_addr16[1] = 0;
425 ip6->ip6_dst.s6_addr32[1] = 0;
426 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE;
427 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3];
428 ip6->ip6_dst.s6_addr8[12] = 0xff;
429 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0)
430 goto bad;
431 }
432 if (!dad) {
433 /*
434 * RFC2461 7.2.2:
435 * "If the source address of the packet prompting the
436 * solicitation is the same as one of the addresses assigned
437 * to the outgoing interface, that address SHOULD be placed
438 * in the IP Source Address of the outgoing solicitation.
439 * Otherwise, any one of the addresses assigned to the
440 * interface should be used."
441 *
442 * We use the source address for the prompting packet
443 * (saddr6), if:
444 * - saddr6 is given from the caller (by giving "ln"), and
445 * - saddr6 belongs to the outgoing interface.
446 * Otherwise, we perform the source address selection as usual.
447 */
448 struct ip6_hdr *hip6; /* hold ip6 */
449 struct in6_addr *hsrc = NULL;
450
451 if (ln && ln->ln_hold) {
452 /*
453 * assuming every packet in ln_hold has the same IP
454 * header
455 */
456 hip6 = mtod(ln->ln_hold, struct ip6_hdr *);
457 /* XXX pullup? */
458 if (sizeof(*hip6) < ln->ln_hold->m_len)
459 hsrc = &hip6->ip6_src;
460 else
461 hsrc = NULL;
462 }
463 if (hsrc && in6ifa_ifpwithaddr(ifp, hsrc))
464 src = hsrc;
465 else {
466 int error;
467 struct sockaddr_in6 dst_sa;
468
469 bzero(&dst_sa, sizeof(dst_sa));
470 dst_sa.sin6_family = AF_INET6;
471 dst_sa.sin6_len = sizeof(dst_sa);
472 dst_sa.sin6_addr = ip6->ip6_dst;
473
474 src = in6_selectsrc(&dst_sa, NULL,
475 NULL, &ro, NULL, NULL, &error);
476 if (src == NULL) {
477 char ip6buf[INET6_ADDRSTRLEN];
478 nd6log((LOG_DEBUG,
479 "nd6_ns_output: source can't be "
480 "determined: dst=%s, error=%d\n",
481 ip6_sprintf(ip6buf, &dst_sa.sin6_addr),
482 error));
483 goto bad;
484 }
485 }
486 } else {
487 /*
488 * Source address for DAD packet must always be IPv6
489 * unspecified address. (0::0)
490 * We actually don't have to 0-clear the address (we did it
491 * above), but we do so here explicitly to make the intention
492 * clearer.
493 */
494 bzero(&src_in, sizeof(src_in));
495 src = &src_in;
496 }
497 ip6->ip6_src = *src;
498 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1);
499 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT;
500 nd_ns->nd_ns_code = 0;
501 nd_ns->nd_ns_reserved = 0;
502 nd_ns->nd_ns_target = *taddr6;
503 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */
504
505 /*
506 * Add source link-layer address option.
507 *
508 * spec implementation
509 * --- ---
510 * DAD packet MUST NOT do not add the option
511 * there's no link layer address:
512 * impossible do not add the option
513 * there's link layer address:
514 * Multicast NS MUST add one add the option
515 * Unicast NS SHOULD add one add the option
516 */
517 if (!dad && (mac = nd6_ifptomac(ifp))) {
518 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
519 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
520 /* 8 byte alignments... */
521 optlen = (optlen + 7) & ~7;
522
523 m->m_pkthdr.len += optlen;
524 m->m_len += optlen;
525 icmp6len += optlen;
526 bzero((caddr_t)nd_opt, optlen);
527 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR;
528 nd_opt->nd_opt_len = optlen >> 3;
529 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
530 }
531
532 ip6->ip6_plen = htons((u_short)icmp6len);
533 nd_ns->nd_ns_cksum = 0;
534 nd_ns->nd_ns_cksum =
535 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len);
536
537 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL);
538 icmp6_ifstat_inc(ifp, ifs6_out_msg);
539 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit);
540 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++;
541
542 if (ro.ro_rt) { /* we don't cache this route. */
543 RTFREE(ro.ro_rt);
544 }
545 return;
546
547 bad:
548 if (ro.ro_rt) {
549 RTFREE(ro.ro_rt);
550 }
551 m_freem(m);
552 return;
553 }
554
555 /*
556 * Neighbor advertisement input handling.
557 *
558 * Based on RFC 2461
559 * Based on RFC 2462 (duplicate address detection)
560 *
561 * the following items are not implemented yet:
562 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
563 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
564 */
565 void
566 nd6_na_input(struct mbuf *m, int off, int icmp6len)
567 {
568 struct ifnet *ifp = m->m_pkthdr.rcvif;
569 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
570 struct nd_neighbor_advert *nd_na;
571 struct in6_addr daddr6 = ip6->ip6_dst;
572 struct in6_addr taddr6;
573 int flags;
574 int is_router;
575 int is_solicited;
576 int is_override;
577 char *lladdr = NULL;
578 int lladdrlen = 0;
579 struct ifaddr *ifa;
580 struct llinfo_nd6 *ln;
581 struct rtentry *rt;
582 struct sockaddr_dl *sdl;
583 union nd_opts ndopts;
584 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
585
586 if (ip6->ip6_hlim != 255) {
587 nd6log((LOG_ERR,
588 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n",
589 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
590 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
591 goto bad;
592 }
593
594 #ifndef PULLDOWN_TEST
595 IP6_EXTHDR_CHECK(m, off, icmp6len,);
596 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off);
597 #else
598 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len);
599 if (nd_na == NULL) {
600 icmp6stat.icp6s_tooshort++;
601 return;
602 }
603 #endif
604
605 flags = nd_na->nd_na_flags_reserved;
606 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0);
607 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0);
608 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0);
609
610 taddr6 = nd_na->nd_na_target;
611 if (in6_setscope(&taddr6, ifp, NULL))
612 goto bad; /* XXX: impossible */
613
614 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
615 nd6log((LOG_ERR,
616 "nd6_na_input: invalid target address %s\n",
617 ip6_sprintf(ip6bufs, &taddr6)));
618 goto bad;
619 }
620 if (IN6_IS_ADDR_MULTICAST(&daddr6))
621 if (is_solicited) {
622 nd6log((LOG_ERR,
623 "nd6_na_input: a solicited adv is multicasted\n"));
624 goto bad;
625 }
626
627 icmp6len -= sizeof(*nd_na);
628 nd6_option_init(nd_na + 1, icmp6len, &ndopts);
629 if (nd6_options(&ndopts) < 0) {
630 nd6log((LOG_INFO,
631 "nd6_na_input: invalid ND option, ignored\n"));
632 /* nd6_options have incremented stats */
633 goto freeit;
634 }
635
636 if (ndopts.nd_opts_tgt_lladdr) {
637 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
638 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
639 }
640
641 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
642
643 /*
644 * Target address matches one of my interface address.
645 *
646 * If my address is tentative, this means that there's somebody
647 * already using the same address as mine. This indicates DAD failure.
648 * This is defined in RFC 2462.
649 *
650 * Otherwise, process as defined in RFC 2461.
651 */
652 if (ifa
653 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) {
654 nd6_dad_na_input(ifa);
655 goto freeit;
656 }
657
658 /* Just for safety, maybe unnecessary. */
659 if (ifa) {
660 log(LOG_ERR,
661 "nd6_na_input: duplicate IP6 address %s\n",
662 ip6_sprintf(ip6bufs, &taddr6));
663 goto freeit;
664 }
665
666 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
667 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s "
668 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6),
669 ifp->if_addrlen, lladdrlen - 2));
670 goto bad;
671 }
672
673 /*
674 * If no neighbor cache entry is found, NA SHOULD silently be
675 * discarded.
676 */
677 rt = nd6_lookup(&taddr6, 0, ifp);
678 if ((rt == NULL) ||
679 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) ||
680 ((sdl = SDL(rt->rt_gateway)) == NULL))
681 goto freeit;
682
683 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
684 /*
685 * If the link-layer has address, and no lladdr option came,
686 * discard the packet.
687 */
688 if (ifp->if_addrlen && lladdr == NULL)
689 goto freeit;
690
691 /*
692 * Record link-layer address, and update the state.
693 */
694 sdl->sdl_alen = ifp->if_addrlen;
695 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
696 if (is_solicited) {
697 ln->ln_state = ND6_LLINFO_REACHABLE;
698 ln->ln_byhint = 0;
699 if (!ND6_LLINFO_PERMANENT(ln)) {
700 nd6_llinfo_settimer(ln,
701 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz);
702 }
703 } else {
704 ln->ln_state = ND6_LLINFO_STALE;
705 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz);
706 }
707 if ((ln->ln_router = is_router) != 0) {
708 /*
709 * This means a router's state has changed from
710 * non-reachable to probably reachable, and might
711 * affect the status of associated prefixes..
712 */
713 pfxlist_onlink_check();
714 }
715 } else {
716 int llchange;
717
718 /*
719 * Check if the link-layer address has changed or not.
720 */
721 if (lladdr == NULL)
722 llchange = 0;
723 else {
724 if (sdl->sdl_alen) {
725 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen))
726 llchange = 1;
727 else
728 llchange = 0;
729 } else
730 llchange = 1;
731 }
732
733 /*
734 * This is VERY complex. Look at it with care.
735 *
736 * override solicit lladdr llchange action
737 * (L: record lladdr)
738 *
739 * 0 0 n -- (2c)
740 * 0 0 y n (2b) L
741 * 0 0 y y (1) REACHABLE->STALE
742 * 0 1 n -- (2c) *->REACHABLE
743 * 0 1 y n (2b) L *->REACHABLE
744 * 0 1 y y (1) REACHABLE->STALE
745 * 1 0 n -- (2a)
746 * 1 0 y n (2a) L
747 * 1 0 y y (2a) L *->STALE
748 * 1 1 n -- (2a) *->REACHABLE
749 * 1 1 y n (2a) L *->REACHABLE
750 * 1 1 y y (2a) L *->REACHABLE
751 */
752 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */
753 /*
754 * If state is REACHABLE, make it STALE.
755 * no other updates should be done.
756 */
757 if (ln->ln_state == ND6_LLINFO_REACHABLE) {
758 ln->ln_state = ND6_LLINFO_STALE;
759 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz);
760 }
761 goto freeit;
762 } else if (is_override /* (2a) */
763 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */
764 || lladdr == NULL) { /* (2c) */
765 /*
766 * Update link-local address, if any.
767 */
768 if (lladdr != NULL) {
769 sdl->sdl_alen = ifp->if_addrlen;
770 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
771 }
772
773 /*
774 * If solicited, make the state REACHABLE.
775 * If not solicited and the link-layer address was
776 * changed, make it STALE.
777 */
778 if (is_solicited) {
779 ln->ln_state = ND6_LLINFO_REACHABLE;
780 ln->ln_byhint = 0;
781 if (!ND6_LLINFO_PERMANENT(ln)) {
782 nd6_llinfo_settimer(ln,
783 (long)ND_IFINFO(ifp)->reachable * hz);
784 }
785 } else {
786 if (lladdr != NULL && llchange) {
787 ln->ln_state = ND6_LLINFO_STALE;
788 nd6_llinfo_settimer(ln,
789 (long)nd6_gctimer * hz);
790 }
791 }
792 }
793
794 if (ln->ln_router && !is_router) {
795 /*
796 * The peer dropped the router flag.
797 * Remove the sender from the Default Router List and
798 * update the Destination Cache entries.
799 */
800 struct nd_defrouter *dr;
801 struct in6_addr *in6;
802 int s;
803
804 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr;
805
806 /*
807 * Lock to protect the default router list.
808 * XXX: this might be unnecessary, since this function
809 * is only called under the network software interrupt
810 * context. However, we keep it just for safety.
811 */
812 s = splnet();
813 dr = defrouter_lookup(in6, ifp);
814 if (dr)
815 defrtrlist_del(dr);
816 else if (!ip6_forwarding) {
817 /*
818 * Even if the neighbor is not in the default
819 * router list, the neighbor may be used
820 * as a next hop for some destinations
821 * (e.g. redirect case). So we must
822 * call rt6_flush explicitly.
823 */
824 rt6_flush(&ip6->ip6_src, ifp);
825 }
826 splx(s);
827 }
828 ln->ln_router = is_router;
829 }
830 rt->rt_flags &= ~RTF_REJECT;
831 ln->ln_asked = 0;
832 if (ln->ln_hold) {
833 struct mbuf *m_hold, *m_hold_next;
834
835 /*
836 * reset the ln_hold in advance, to explicitly
837 * prevent a ln_hold lookup in nd6_output()
838 * (wouldn't happen, though...)
839 */
840 for (m_hold = ln->ln_hold;
841 m_hold; m_hold = m_hold_next) {
842 m_hold_next = m_hold->m_nextpkt;
843 m_hold->m_nextpkt = NULL;
844 /*
845 * we assume ifp is not a loopback here, so just set
846 * the 2nd argument as the 1st one.
847 */
848 nd6_output(ifp, ifp, m_hold,
849 (struct sockaddr_in6 *)rt_key(rt), rt);
850 }
851 ln->ln_hold = NULL;
852 }
853
854 freeit:
855 m_freem(m);
856 return;
857
858 bad:
859 icmp6stat.icp6s_badna++;
860 m_freem(m);
861 }
862
863 /*
864 * Neighbor advertisement output handling.
865 *
866 * Based on RFC 2461
867 *
868 * the following items are not implemented yet:
869 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
870 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
871 *
872 * tlladdr - 1 if include target link-layer address
873 * sdl0 - sockaddr_dl (= proxy NA) or NULL
874 */
875 void
876 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0,
877 const struct in6_addr *taddr6, u_long flags, int tlladdr,
878 struct sockaddr *sdl0)
879 {
880 struct mbuf *m;
881 struct ip6_hdr *ip6;
882 struct nd_neighbor_advert *nd_na;
883 struct ip6_moptions im6o;
884 struct in6_addr *src, daddr6;
885 struct sockaddr_in6 dst_sa;
886 int icmp6len, maxlen, error;
887 caddr_t mac = NULL;
888 struct route_in6 ro;
889
890 bzero(&ro, sizeof(ro));
891
892 daddr6 = *daddr6_0; /* make a local copy for modification */
893
894 /* estimate the size of message */
895 maxlen = sizeof(*ip6) + sizeof(*nd_na);
896 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
897 if (max_linkhdr + maxlen >= MCLBYTES) {
898 #ifdef DIAGNOSTIC
899 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES "
900 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
901 #endif
902 return;
903 }
904
905 MGETHDR(m, M_DONTWAIT, MT_DATA);
906 if (m && max_linkhdr + maxlen >= MHLEN) {
907 MCLGET(m, M_DONTWAIT);
908 if ((m->m_flags & M_EXT) == 0) {
909 m_free(m);
910 m = NULL;
911 }
912 }
913 if (m == NULL)
914 return;
915 m->m_pkthdr.rcvif = NULL;
916
917 if (IN6_IS_ADDR_MULTICAST(&daddr6)) {
918 m->m_flags |= M_MCAST;
919 im6o.im6o_multicast_ifp = ifp;
920 im6o.im6o_multicast_hlim = 255;
921 im6o.im6o_multicast_loop = 0;
922 }
923
924 icmp6len = sizeof(*nd_na);
925 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len;
926 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
927
928 /* fill neighbor advertisement packet */
929 ip6 = mtod(m, struct ip6_hdr *);
930 ip6->ip6_flow = 0;
931 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
932 ip6->ip6_vfc |= IPV6_VERSION;
933 ip6->ip6_nxt = IPPROTO_ICMPV6;
934 ip6->ip6_hlim = 255;
935 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) {
936 /* reply to DAD */
937 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
938 daddr6.s6_addr16[1] = 0;
939 daddr6.s6_addr32[1] = 0;
940 daddr6.s6_addr32[2] = 0;
941 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE;
942 if (in6_setscope(&daddr6, ifp, NULL))
943 goto bad;
944
945 flags &= ~ND_NA_FLAG_SOLICITED;
946 }
947 ip6->ip6_dst = daddr6;
948 bzero(&dst_sa, sizeof(struct sockaddr_in6));
949 dst_sa.sin6_family = AF_INET6;
950 dst_sa.sin6_len = sizeof(struct sockaddr_in6);
951 dst_sa.sin6_addr = daddr6;
952
953 /*
954 * Select a source whose scope is the same as that of the dest.
955 */
956 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa));
957 src = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &error);
958 if (src == NULL) {
959 char ip6buf[INET6_ADDRSTRLEN];
960 nd6log((LOG_DEBUG, "nd6_na_output: source can't be "
961 "determined: dst=%s, error=%d\n",
962 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error));
963 goto bad;
964 }
965 ip6->ip6_src = *src;
966 nd_na = (struct nd_neighbor_advert *)(ip6 + 1);
967 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT;
968 nd_na->nd_na_code = 0;
969 nd_na->nd_na_target = *taddr6;
970 in6_clearscope(&nd_na->nd_na_target); /* XXX */
971
972 /*
973 * "tlladdr" indicates NS's condition for adding tlladdr or not.
974 * see nd6_ns_input() for details.
975 * Basically, if NS packet is sent to unicast/anycast addr,
976 * target lladdr option SHOULD NOT be included.
977 */
978 if (tlladdr) {
979 /*
980 * sdl0 != NULL indicates proxy NA. If we do proxy, use
981 * lladdr in sdl0. If we are not proxying (sending NA for
982 * my address) use lladdr configured for the interface.
983 */
984 if (sdl0 == NULL) {
985 #ifdef DEV_CARP
986 if (ifp->if_carp)
987 mac = carp_macmatch6(ifp->if_carp, m, taddr6);
988 if (mac == NULL)
989 mac = nd6_ifptomac(ifp);
990 #else
991 mac = nd6_ifptomac(ifp);
992 #endif
993 } else if (sdl0->sa_family == AF_LINK) {
994 struct sockaddr_dl *sdl;
995 sdl = (struct sockaddr_dl *)sdl0;
996 if (sdl->sdl_alen == ifp->if_addrlen)
997 mac = LLADDR(sdl);
998 }
999 }
1000 if (tlladdr && mac) {
1001 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
1002 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1);
1003
1004 /* roundup to 8 bytes alignment! */
1005 optlen = (optlen + 7) & ~7;
1006
1007 m->m_pkthdr.len += optlen;
1008 m->m_len += optlen;
1009 icmp6len += optlen;
1010 bzero((caddr_t)nd_opt, optlen);
1011 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
1012 nd_opt->nd_opt_len = optlen >> 3;
1013 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
1014 } else
1015 flags &= ~ND_NA_FLAG_OVERRIDE;
1016
1017 ip6->ip6_plen = htons((u_short)icmp6len);
1018 nd_na->nd_na_flags_reserved = flags;
1019 nd_na->nd_na_cksum = 0;
1020 nd_na->nd_na_cksum =
1021 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len);
1022
1023 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL);
1024 icmp6_ifstat_inc(ifp, ifs6_out_msg);
1025 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert);
1026 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++;
1027
1028 if (ro.ro_rt) { /* we don't cache this route. */
1029 RTFREE(ro.ro_rt);
1030 }
1031 return;
1032
1033 bad:
1034 if (ro.ro_rt) {
1035 RTFREE(ro.ro_rt);
1036 }
1037 m_freem(m);
1038 return;
1039 }
1040
1041 caddr_t
1042 nd6_ifptomac(struct ifnet *ifp)
1043 {
1044 switch (ifp->if_type) {
1045 case IFT_ARCNET:
1046 case IFT_ETHER:
1047 case IFT_FDDI:
1048 case IFT_IEEE1394:
1049 #ifdef IFT_L2VLAN
1050 case IFT_L2VLAN:
1051 #endif
1052 #ifdef IFT_IEEE80211
1053 case IFT_IEEE80211:
1054 #endif
1055 #ifdef IFT_CARP
1056 case IFT_CARP:
1057 #endif
1058 case IFT_BRIDGE:
1059 case IFT_ISO88025:
1060 return IF_LLADDR(ifp);
1061 default:
1062 return NULL;
1063 }
1064 }
1065
1066 TAILQ_HEAD(dadq_head, dadq);
1067 struct dadq {
1068 TAILQ_ENTRY(dadq) dad_list;
1069 struct ifaddr *dad_ifa;
1070 int dad_count; /* max NS to send */
1071 int dad_ns_tcount; /* # of trials to send NS */
1072 int dad_ns_ocount; /* NS sent so far */
1073 int dad_ns_icount;
1074 int dad_na_icount;
1075 struct callout dad_timer_ch;
1076 };
1077
1078 static struct dadq_head dadq;
1079 static int dad_init = 0;
1080
1081 static struct dadq *
1082 nd6_dad_find(struct ifaddr *ifa)
1083 {
1084 struct dadq *dp;
1085
1086 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) {
1087 if (dp->dad_ifa == ifa)
1088 return dp;
1089 }
1090 return NULL;
1091 }
1092
1093 static void
1094 nd6_dad_starttimer(struct dadq *dp, int ticks)
1095 {
1096
1097 callout_reset(&dp->dad_timer_ch, ticks,
1098 (void (*) __P((void *)))nd6_dad_timer, (void *)dp->dad_ifa);
1099 }
1100
1101 static void
1102 nd6_dad_stoptimer(struct dadq *dp)
1103 {
1104
1105 callout_stop(&dp->dad_timer_ch);
1106 }
1107
1108 /*
1109 * Start Duplicate Address Detection (DAD) for specified interface address.
1110 */
1111 void
1112 nd6_dad_start(struct ifaddr *ifa, int delay)
1113 {
1114 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1115 struct dadq *dp;
1116 char ip6buf[INET6_ADDRSTRLEN];
1117
1118 if (!dad_init) {
1119 TAILQ_INIT(&dadq);
1120 dad_init++;
1121 }
1122
1123 /*
1124 * If we don't need DAD, don't do it.
1125 * There are several cases:
1126 * - DAD is disabled (ip6_dad_count == 0)
1127 * - the interface address is anycast
1128 */
1129 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
1130 log(LOG_DEBUG,
1131 "nd6_dad_start: called with non-tentative address "
1132 "%s(%s)\n",
1133 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1134 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1135 return;
1136 }
1137 if (ia->ia6_flags & IN6_IFF_ANYCAST) {
1138 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1139 return;
1140 }
1141 if (!ip6_dad_count) {
1142 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1143 return;
1144 }
1145 if (ifa->ifa_ifp == NULL)
1146 panic("nd6_dad_start: ifa->ifa_ifp == NULL");
1147 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) {
1148 return;
1149 }
1150 if (nd6_dad_find(ifa) != NULL) {
1151 /* DAD already in progress */
1152 return;
1153 }
1154
1155 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT);
1156 if (dp == NULL) {
1157 log(LOG_ERR, "nd6_dad_start: memory allocation failed for "
1158 "%s(%s)\n",
1159 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1160 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1161 return;
1162 }
1163 bzero(dp, sizeof(*dp));
1164 callout_init(&dp->dad_timer_ch, 0);
1165 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list);
1166
1167 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp),
1168 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1169
1170 /*
1171 * Send NS packet for DAD, ip6_dad_count times.
1172 * Note that we must delay the first transmission, if this is the
1173 * first packet to be sent from the interface after interface
1174 * (re)initialization.
1175 */
1176 dp->dad_ifa = ifa;
1177 IFAREF(ifa); /* just for safety */
1178 dp->dad_count = ip6_dad_count;
1179 dp->dad_ns_icount = dp->dad_na_icount = 0;
1180 dp->dad_ns_ocount = dp->dad_ns_tcount = 0;
1181 if (delay == 0) {
1182 nd6_dad_ns_output(dp, ifa);
1183 nd6_dad_starttimer(dp,
1184 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1185 } else {
1186 nd6_dad_starttimer(dp, delay);
1187 }
1188 }
1189
1190 /*
1191 * terminate DAD unconditionally. used for address removals.
1192 */
1193 void
1194 nd6_dad_stop(struct ifaddr *ifa)
1195 {
1196 struct dadq *dp;
1197
1198 if (!dad_init)
1199 return;
1200 dp = nd6_dad_find(ifa);
1201 if (!dp) {
1202 /* DAD wasn't started yet */
1203 return;
1204 }
1205
1206 nd6_dad_stoptimer(dp);
1207
1208 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1209 free(dp, M_IP6NDP);
1210 dp = NULL;
1211 IFAFREE(ifa);
1212 }
1213
1214 static void
1215 nd6_dad_timer(struct ifaddr *ifa)
1216 {
1217 int s;
1218 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1219 struct dadq *dp;
1220 char ip6buf[INET6_ADDRSTRLEN];
1221
1222 s = splnet(); /* XXX */
1223
1224 /* Sanity check */
1225 if (ia == NULL) {
1226 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n");
1227 goto done;
1228 }
1229 dp = nd6_dad_find(ifa);
1230 if (dp == NULL) {
1231 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n");
1232 goto done;
1233 }
1234 if (ia->ia6_flags & IN6_IFF_DUPLICATED) {
1235 log(LOG_ERR, "nd6_dad_timer: called with duplicated address "
1236 "%s(%s)\n",
1237 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1238 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1239 goto done;
1240 }
1241 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) {
1242 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address "
1243 "%s(%s)\n",
1244 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1245 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1246 goto done;
1247 }
1248
1249 /* timeouted with IFF_{RUNNING,UP} check */
1250 if (dp->dad_ns_tcount > dad_maxtry) {
1251 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n",
1252 if_name(ifa->ifa_ifp)));
1253
1254 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1255 free(dp, M_IP6NDP);
1256 dp = NULL;
1257 IFAFREE(ifa);
1258 goto done;
1259 }
1260
1261 /* Need more checks? */
1262 if (dp->dad_ns_ocount < dp->dad_count) {
1263 /*
1264 * We have more NS to go. Send NS packet for DAD.
1265 */
1266 nd6_dad_ns_output(dp, ifa);
1267 nd6_dad_starttimer(dp,
1268 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1269 } else {
1270 /*
1271 * We have transmitted sufficient number of DAD packets.
1272 * See what we've got.
1273 */
1274 int duplicate;
1275
1276 duplicate = 0;
1277
1278 if (dp->dad_na_icount) {
1279 /*
1280 * the check is in nd6_dad_na_input(),
1281 * but just in case
1282 */
1283 duplicate++;
1284 }
1285
1286 if (dp->dad_ns_icount) {
1287 /* We've seen NS, means DAD has failed. */
1288 duplicate++;
1289 }
1290
1291 if (duplicate) {
1292 /* (*dp) will be freed in nd6_dad_duplicated() */
1293 dp = NULL;
1294 nd6_dad_duplicated(ifa);
1295 } else {
1296 /*
1297 * We are done with DAD. No NA came, no NS came.
1298 * No duplicate address found.
1299 */
1300 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1301
1302 nd6log((LOG_DEBUG,
1303 "%s: DAD complete for %s - no duplicates found\n",
1304 if_name(ifa->ifa_ifp),
1305 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1306
1307 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1308 free(dp, M_IP6NDP);
1309 dp = NULL;
1310 IFAFREE(ifa);
1311 }
1312 }
1313
1314 done:
1315 splx(s);
1316 }
1317
1318 void
1319 nd6_dad_duplicated(struct ifaddr *ifa)
1320 {
1321 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1322 struct ifnet *ifp;
1323 struct dadq *dp;
1324 char ip6buf[INET6_ADDRSTRLEN];
1325
1326 dp = nd6_dad_find(ifa);
1327 if (dp == NULL) {
1328 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n");
1329 return;
1330 }
1331
1332 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: "
1333 "NS in/out=%d/%d, NA in=%d\n",
1334 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1335 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount);
1336
1337 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1338 ia->ia6_flags |= IN6_IFF_DUPLICATED;
1339
1340 /* We are done with DAD, with duplicate address found. (failure) */
1341 nd6_dad_stoptimer(dp);
1342
1343 ifp = ifa->ifa_ifp;
1344 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n",
1345 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr));
1346 log(LOG_ERR, "%s: manual intervention required\n",
1347 if_name(ifp));
1348
1349 /*
1350 * If the address is a link-local address formed from an interface
1351 * identifier based on the hardware address which is supposed to be
1352 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP
1353 * operation on the interface SHOULD be disabled.
1354 * [rfc2462bis-03 Section 5.4.5]
1355 */
1356 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) {
1357 struct in6_addr in6;
1358
1359 /*
1360 * To avoid over-reaction, we only apply this logic when we are
1361 * very sure that hardware addresses are supposed to be unique.
1362 */
1363 switch (ifp->if_type) {
1364 case IFT_ETHER:
1365 case IFT_FDDI:
1366 case IFT_ATM:
1367 case IFT_IEEE1394:
1368 #ifdef IFT_IEEE80211
1369 case IFT_IEEE80211:
1370 #endif
1371 in6 = ia->ia_addr.sin6_addr;
1372 if (in6_get_hw_ifid(ifp, &in6) == 0 &&
1373 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) {
1374 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED;
1375 log(LOG_ERR, "%s: possible hardware address "
1376 "duplication detected, disable IPv6\n",
1377 if_name(ifp));
1378 }
1379 break;
1380 }
1381 }
1382
1383 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1384 free(dp, M_IP6NDP);
1385 dp = NULL;
1386 IFAFREE(ifa);
1387 }
1388
1389 static void
1390 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa)
1391 {
1392 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1393 struct ifnet *ifp = ifa->ifa_ifp;
1394
1395 dp->dad_ns_tcount++;
1396 if ((ifp->if_flags & IFF_UP) == 0) {
1397 return;
1398 }
1399 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
1400 return;
1401 }
1402
1403 dp->dad_ns_ocount++;
1404 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1);
1405 }
1406
1407 static void
1408 nd6_dad_ns_input(struct ifaddr *ifa)
1409 {
1410 struct in6_ifaddr *ia;
1411 struct ifnet *ifp;
1412 const struct in6_addr *taddr6;
1413 struct dadq *dp;
1414 int duplicate;
1415
1416 if (ifa == NULL)
1417 panic("ifa == NULL in nd6_dad_ns_input");
1418
1419 ia = (struct in6_ifaddr *)ifa;
1420 ifp = ifa->ifa_ifp;
1421 taddr6 = &ia->ia_addr.sin6_addr;
1422 duplicate = 0;
1423 dp = nd6_dad_find(ifa);
1424
1425 /* Quickhack - completely ignore DAD NS packets */
1426 if (dad_ignore_ns) {
1427 char ip6buf[INET6_ADDRSTRLEN];
1428 nd6log((LOG_INFO,
1429 "nd6_dad_ns_input: ignoring DAD NS packet for "
1430 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6),
1431 if_name(ifa->ifa_ifp)));
1432 return;
1433 }
1434
1435 /*
1436 * if I'm yet to start DAD, someone else started using this address
1437 * first. I have a duplicate and you win.
1438 */
1439 if (dp == NULL || dp->dad_ns_ocount == 0)
1440 duplicate++;
1441
1442 /* XXX more checks for loopback situation - see nd6_dad_timer too */
1443
1444 if (duplicate) {
1445 dp = NULL; /* will be freed in nd6_dad_duplicated() */
1446 nd6_dad_duplicated(ifa);
1447 } else {
1448 /*
1449 * not sure if I got a duplicate.
1450 * increment ns count and see what happens.
1451 */
1452 if (dp)
1453 dp->dad_ns_icount++;
1454 }
1455 }
1456
1457 static void
1458 nd6_dad_na_input(struct ifaddr *ifa)
1459 {
1460 struct dadq *dp;
1461
1462 if (ifa == NULL)
1463 panic("ifa == NULL in nd6_dad_na_input");
1464
1465 dp = nd6_dad_find(ifa);
1466 if (dp)
1467 dp->dad_na_icount++;
1468
1469 /* remove the address. */
1470 nd6_dad_duplicated(ifa);
1471 }
Cache object: f664000caac92d0cc6692aaf2bfb9aff
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