1 /* $FreeBSD: releng/5.4/sys/netinet6/nd6_nbr.c 143925 2005-03-21 16:05:36Z glebius $ */
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/route.h>
55
56 #include <netinet/in.h>
57 #include <netinet/in_var.h>
58 #include <netinet6/in6_var.h>
59 #include <netinet/ip6.h>
60 #include <netinet6/ip6_var.h>
61 #include <netinet6/nd6.h>
62 #include <netinet/icmp6.h>
63
64 #ifdef DEV_CARP
65 #include <netinet/ip_carp.h>
66 #endif
67
68 #include <net/net_osdep.h>
69
70 #define SDL(s) ((struct sockaddr_dl *)s)
71
72 struct dadq;
73 static struct dadq *nd6_dad_find __P((struct ifaddr *));
74 static void nd6_dad_starttimer __P((struct dadq *, int));
75 static void nd6_dad_stoptimer __P((struct dadq *));
76 static void nd6_dad_timer __P((struct ifaddr *));
77 static void nd6_dad_ns_output __P((struct dadq *, struct ifaddr *));
78 static void nd6_dad_ns_input __P((struct ifaddr *));
79 static void nd6_dad_na_input __P((struct ifaddr *));
80
81 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/
82 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */
83
84 /*
85 * Input a Neighbor Solicitation Message.
86 *
87 * Based on RFC 2461
88 * Based on RFC 2462 (duplicated address detection)
89 */
90 void
91 nd6_ns_input(m, off, icmp6len)
92 struct mbuf *m;
93 int off, icmp6len;
94 {
95 struct ifnet *ifp = m->m_pkthdr.rcvif;
96 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
97 struct nd_neighbor_solicit *nd_ns;
98 struct in6_addr saddr6 = ip6->ip6_src;
99 struct in6_addr daddr6 = ip6->ip6_dst;
100 struct in6_addr taddr6;
101 struct in6_addr myaddr6;
102 char *lladdr = NULL;
103 struct ifaddr *ifa = NULL;
104 int lladdrlen = 0;
105 int anycast = 0, proxy = 0, tentative = 0;
106 int tlladdr;
107 union nd_opts ndopts;
108 struct sockaddr_dl *proxydl = NULL;
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
123 if (ip6->ip6_hlim != 255) {
124 nd6log((LOG_ERR,
125 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n",
126 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src),
127 ip6_sprintf(&ip6->ip6_dst), if_name(ifp)));
128 goto bad;
129 }
130
131 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
132 /* dst has to be solicited node multicast address. */
133 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL &&
134 /* don't check ifindex portion */
135 daddr6.s6_addr32[1] == 0 &&
136 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE &&
137 daddr6.s6_addr8[12] == 0xff) {
138 ; /* good */
139 } else {
140 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
141 "(wrong ip6 dst)\n"));
142 goto bad;
143 }
144 }
145
146 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
147 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n"));
148 goto bad;
149 }
150
151 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6))
152 taddr6.s6_addr16[1] = htons(ifp->if_index);
153
154 icmp6len -= sizeof(*nd_ns);
155 nd6_option_init(nd_ns + 1, icmp6len, &ndopts);
156 if (nd6_options(&ndopts) < 0) {
157 nd6log((LOG_INFO,
158 "nd6_ns_input: invalid ND option, ignored\n"));
159 /* nd6_options have incremented stats */
160 goto freeit;
161 }
162
163 if (ndopts.nd_opts_src_lladdr) {
164 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
165 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
166 }
167
168 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) {
169 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
170 "(link-layer address option)\n"));
171 goto bad;
172 }
173
174 /*
175 * Attaching target link-layer address to the NA?
176 * (RFC 2461 7.2.4)
177 *
178 * NS IP dst is unicast/anycast MUST NOT add
179 * NS IP dst is solicited-node multicast MUST add
180 *
181 * In implementation, we add target link-layer address by default.
182 * We do not add one in MUST NOT cases.
183 */
184 #if 0 /* too much! */
185 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6);
186 if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST))
187 tlladdr = 0;
188 else
189 #endif
190 if (!IN6_IS_ADDR_MULTICAST(&daddr6))
191 tlladdr = 0;
192 else
193 tlladdr = 1;
194
195 /*
196 * Target address (taddr6) must be either:
197 * (1) Valid unicast/anycast address for my receiving interface,
198 * (2) Unicast address for which I'm offering proxy service, or
199 * (3) "tentative" address on which DAD is being performed.
200 */
201 /* (1) and (3) check. */
202 #ifdef DEV_CARP
203 if (ifp->if_carp)
204 ifa = carp_iamatch6(ifp->if_carp, &taddr6);
205 if (!ifa)
206 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
207 #else
208 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
209 #endif
210
211 /* (2) check. */
212 if (!ifa) {
213 struct rtentry *rt;
214 struct sockaddr_in6 tsin6;
215 int need_proxy;
216
217 bzero(&tsin6, sizeof tsin6);
218 tsin6.sin6_len = sizeof(struct sockaddr_in6);
219 tsin6.sin6_family = AF_INET6;
220 tsin6.sin6_addr = taddr6;
221
222 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0);
223 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 &&
224 rt->rt_gateway->sa_family == AF_LINK);
225 if (rt)
226 rtfree(rt);
227 if (need_proxy) {
228 /*
229 * proxy NDP for single entry
230 */
231 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp,
232 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
233 if (ifa) {
234 proxy = 1;
235 proxydl = SDL(rt->rt_gateway);
236 }
237 }
238 }
239 if (!ifa) {
240 /*
241 * We've got an NS packet, and we don't have that adddress
242 * assigned for us. We MUST silently ignore it.
243 * See RFC2461 7.2.3.
244 */
245 goto freeit;
246 }
247 myaddr6 = *IFA_IN6(ifa);
248 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST;
249 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE;
250 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED)
251 goto freeit;
252
253 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
254 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s "
255 "(if %d, NS packet %d)\n",
256 ip6_sprintf(&taddr6),
257 ifp->if_addrlen, lladdrlen - 2));
258 goto bad;
259 }
260
261 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) {
262 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n",
263 ip6_sprintf(&saddr6)));
264 goto freeit;
265 }
266
267 /*
268 * We have neighbor solicitation packet, with target address equals to
269 * one of my tentative address.
270 *
271 * src addr how to process?
272 * --- ---
273 * multicast of course, invalid (rejected in ip6_input)
274 * unicast somebody is doing address resolution -> ignore
275 * unspec dup address detection
276 *
277 * The processing is defined in RFC 2462.
278 */
279 if (tentative) {
280 /*
281 * If source address is unspecified address, it is for
282 * duplicated address detection.
283 *
284 * If not, the packet is for addess resolution;
285 * silently ignore it.
286 */
287 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6))
288 nd6_dad_ns_input(ifa);
289
290 goto freeit;
291 }
292
293 /*
294 * If the source address is unspecified address, entries must not
295 * be created or updated.
296 * It looks that sender is performing DAD. Output NA toward
297 * all-node multicast address, to tell the sender that I'm using
298 * the address.
299 * S bit ("solicited") must be zero.
300 */
301 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
302 saddr6 = in6addr_linklocal_allnodes;
303 saddr6.s6_addr16[1] = htons(ifp->if_index);
304 nd6_na_output(ifp, &saddr6, &taddr6,
305 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
306 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0),
307 tlladdr, (struct sockaddr *)proxydl);
308 goto freeit;
309 }
310
311 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen,
312 ND_NEIGHBOR_SOLICIT, 0);
313
314 nd6_na_output(ifp, &saddr6, &taddr6,
315 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
316 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED,
317 tlladdr, (struct sockaddr *)proxydl);
318 freeit:
319 m_freem(m);
320 return;
321
322 bad:
323 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", ip6_sprintf(&saddr6)));
324 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", ip6_sprintf(&daddr6)));
325 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", ip6_sprintf(&taddr6)));
326 icmp6stat.icp6s_badns++;
327 m_freem(m);
328 }
329
330 /*
331 * Output a Neighbor Solicitation Message. Caller specifies:
332 * - ICMP6 header source IP6 address
333 * - ND6 header target IP6 address
334 * - ND6 header source datalink address
335 *
336 * Based on RFC 2461
337 * Based on RFC 2462 (duplicated address detection)
338 */
339 void
340 nd6_ns_output(ifp, daddr6, taddr6, ln, dad)
341 struct ifnet *ifp;
342 const struct in6_addr *daddr6, *taddr6;
343 struct llinfo_nd6 *ln; /* for source address determination */
344 int dad; /* duplicated address detection */
345 {
346 struct mbuf *m;
347 struct ip6_hdr *ip6;
348 struct nd_neighbor_solicit *nd_ns;
349 struct in6_ifaddr *ia = NULL;
350 struct ip6_moptions im6o;
351 int icmp6len;
352 int maxlen;
353 caddr_t mac;
354 struct ifnet *outif = NULL;
355
356 if (IN6_IS_ADDR_MULTICAST(taddr6))
357 return;
358
359 /* estimate the size of message */
360 maxlen = sizeof(*ip6) + sizeof(*nd_ns);
361 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
362 if (max_linkhdr + maxlen >= MCLBYTES) {
363 #ifdef DIAGNOSTIC
364 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES "
365 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
366 #endif
367 return;
368 }
369
370 MGETHDR(m, M_DONTWAIT, MT_DATA);
371 if (m && max_linkhdr + maxlen >= MHLEN) {
372 MCLGET(m, M_DONTWAIT);
373 if ((m->m_flags & M_EXT) == 0) {
374 m_free(m);
375 m = NULL;
376 }
377 }
378 if (m == NULL)
379 return;
380 m->m_pkthdr.rcvif = NULL;
381
382 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) {
383 m->m_flags |= M_MCAST;
384 im6o.im6o_multicast_ifp = ifp;
385 im6o.im6o_multicast_hlim = 255;
386 im6o.im6o_multicast_loop = 0;
387 }
388
389 icmp6len = sizeof(*nd_ns);
390 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len;
391 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
392
393 /* fill neighbor solicitation packet */
394 ip6 = mtod(m, struct ip6_hdr *);
395 ip6->ip6_flow = 0;
396 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
397 ip6->ip6_vfc |= IPV6_VERSION;
398 /* ip6->ip6_plen will be set later */
399 ip6->ip6_nxt = IPPROTO_ICMPV6;
400 ip6->ip6_hlim = 255;
401 if (daddr6)
402 ip6->ip6_dst = *daddr6;
403 else {
404 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
405 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index);
406 ip6->ip6_dst.s6_addr32[1] = 0;
407 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE;
408 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3];
409 ip6->ip6_dst.s6_addr8[12] = 0xff;
410 }
411 if (!dad) {
412 /*
413 * RFC2461 7.2.2:
414 * "If the source address of the packet prompting the
415 * solicitation is the same as one of the addresses assigned
416 * to the outgoing interface, that address SHOULD be placed
417 * in the IP Source Address of the outgoing solicitation.
418 * Otherwise, any one of the addresses assigned to the
419 * interface should be used."
420 *
421 * We use the source address for the prompting packet
422 * (saddr6), if:
423 * - saddr6 is given from the caller (by giving "ln"), and
424 * - saddr6 belongs to the outgoing interface.
425 * Otherwise, we perform a scope-wise match.
426 */
427 struct ip6_hdr *hip6; /* hold ip6 */
428 struct in6_addr *saddr6;
429
430 if (ln && ln->ln_hold) {
431 hip6 = mtod(ln->ln_hold, struct ip6_hdr *);
432 /* XXX pullup? */
433 if (sizeof(*hip6) < ln->ln_hold->m_len)
434 saddr6 = &hip6->ip6_src;
435 else
436 saddr6 = NULL;
437 } else
438 saddr6 = NULL;
439 if (saddr6 && in6ifa_ifpwithaddr(ifp, saddr6))
440 bcopy(saddr6, &ip6->ip6_src, sizeof(*saddr6));
441 else {
442 ia = in6_ifawithifp(ifp, &ip6->ip6_dst);
443 if (ia == NULL) {
444 m_freem(m);
445 return;
446 }
447 ip6->ip6_src = ia->ia_addr.sin6_addr;
448 }
449 } else {
450 /*
451 * Source address for DAD packet must always be IPv6
452 * unspecified address. (0::0)
453 */
454 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src));
455 }
456 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1);
457 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT;
458 nd_ns->nd_ns_code = 0;
459 nd_ns->nd_ns_reserved = 0;
460 nd_ns->nd_ns_target = *taddr6;
461 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */
462
463 /*
464 * Add source link-layer address option.
465 *
466 * spec implementation
467 * --- ---
468 * DAD packet MUST NOT do not add the option
469 * there's no link layer address:
470 * impossible do not add the option
471 * there's link layer address:
472 * Multicast NS MUST add one add the option
473 * Unicast NS SHOULD add one add the option
474 */
475 if (!dad && (mac = nd6_ifptomac(ifp))) {
476 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
477 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
478 /* 8 byte alignments... */
479 optlen = (optlen + 7) & ~7;
480
481 m->m_pkthdr.len += optlen;
482 m->m_len += optlen;
483 icmp6len += optlen;
484 bzero((caddr_t)nd_opt, optlen);
485 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR;
486 nd_opt->nd_opt_len = optlen >> 3;
487 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
488 }
489
490 ip6->ip6_plen = htons((u_short)icmp6len);
491 nd_ns->nd_ns_cksum = 0;
492 nd_ns->nd_ns_cksum =
493 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len);
494
495 ip6_output(m, NULL, NULL, dad ? IPV6_DADOUTPUT : 0, &im6o, &outif, NULL);
496 if (outif) {
497 icmp6_ifstat_inc(outif, ifs6_out_msg);
498 icmp6_ifstat_inc(outif, ifs6_out_neighborsolicit);
499 }
500 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++;
501 }
502
503 /*
504 * Neighbor advertisement input handling.
505 *
506 * Based on RFC 2461
507 * Based on RFC 2462 (duplicated address detection)
508 *
509 * the following items are not implemented yet:
510 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
511 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
512 */
513 void
514 nd6_na_input(m, off, icmp6len)
515 struct mbuf *m;
516 int off, icmp6len;
517 {
518 struct ifnet *ifp = m->m_pkthdr.rcvif;
519 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
520 struct nd_neighbor_advert *nd_na;
521 struct in6_addr daddr6 = ip6->ip6_dst;
522 struct in6_addr taddr6;
523 int flags;
524 int is_router;
525 int is_solicited;
526 int is_override;
527 char *lladdr = NULL;
528 int lladdrlen = 0;
529 struct ifaddr *ifa;
530 struct llinfo_nd6 *ln;
531 struct rtentry *rt;
532 struct sockaddr_dl *sdl;
533 union nd_opts ndopts;
534
535 if (ip6->ip6_hlim != 255) {
536 nd6log((LOG_ERR,
537 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n",
538 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src),
539 ip6_sprintf(&ip6->ip6_dst), if_name(ifp)));
540 goto bad;
541 }
542
543 #ifndef PULLDOWN_TEST
544 IP6_EXTHDR_CHECK(m, off, icmp6len,);
545 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off);
546 #else
547 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len);
548 if (nd_na == NULL) {
549 icmp6stat.icp6s_tooshort++;
550 return;
551 }
552 #endif
553 taddr6 = nd_na->nd_na_target;
554 flags = nd_na->nd_na_flags_reserved;
555 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0);
556 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0);
557 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0);
558
559 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6))
560 taddr6.s6_addr16[1] = htons(ifp->if_index);
561
562 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
563 nd6log((LOG_ERR,
564 "nd6_na_input: invalid target address %s\n",
565 ip6_sprintf(&taddr6)));
566 goto bad;
567 }
568 if (IN6_IS_ADDR_MULTICAST(&daddr6))
569 if (is_solicited) {
570 nd6log((LOG_ERR,
571 "nd6_na_input: a solicited adv is multicasted\n"));
572 goto bad;
573 }
574
575 icmp6len -= sizeof(*nd_na);
576 nd6_option_init(nd_na + 1, icmp6len, &ndopts);
577 if (nd6_options(&ndopts) < 0) {
578 nd6log((LOG_INFO,
579 "nd6_na_input: invalid ND option, ignored\n"));
580 /* nd6_options have incremented stats */
581 goto freeit;
582 }
583
584 if (ndopts.nd_opts_tgt_lladdr) {
585 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
586 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
587 }
588
589 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
590
591 /*
592 * Target address matches one of my interface address.
593 *
594 * If my address is tentative, this means that there's somebody
595 * already using the same address as mine. This indicates DAD failure.
596 * This is defined in RFC 2462.
597 *
598 * Otherwise, process as defined in RFC 2461.
599 */
600 if (ifa
601 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) {
602 nd6_dad_na_input(ifa);
603 goto freeit;
604 }
605
606 /* Just for safety, maybe unnecessary. */
607 if (ifa) {
608 log(LOG_ERR,
609 "nd6_na_input: duplicate IP6 address %s\n",
610 ip6_sprintf(&taddr6));
611 goto freeit;
612 }
613
614 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
615 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s "
616 "(if %d, NA packet %d)\n", ip6_sprintf(&taddr6),
617 ifp->if_addrlen, lladdrlen - 2));
618 goto bad;
619 }
620
621 /*
622 * If no neighbor cache entry is found, NA SHOULD silently be
623 * discarded.
624 */
625 rt = nd6_lookup(&taddr6, 0, ifp);
626 if ((rt == NULL) ||
627 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) ||
628 ((sdl = SDL(rt->rt_gateway)) == NULL))
629 goto freeit;
630
631 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
632 /*
633 * If the link-layer has address, and no lladdr option came,
634 * discard the packet.
635 */
636 if (ifp->if_addrlen && !lladdr)
637 goto freeit;
638
639 /*
640 * Record link-layer address, and update the state.
641 */
642 sdl->sdl_alen = ifp->if_addrlen;
643 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
644 if (is_solicited) {
645 ln->ln_state = ND6_LLINFO_REACHABLE;
646 ln->ln_byhint = 0;
647 if (ln->ln_expire) {
648 ln->ln_expire = time_second +
649 ND_IFINFO(rt->rt_ifp)->reachable;
650 }
651 } else {
652 ln->ln_state = ND6_LLINFO_STALE;
653 ln->ln_expire = time_second + nd6_gctimer;
654 }
655 if ((ln->ln_router = is_router) != 0) {
656 /*
657 * This means a router's state has changed from
658 * non-reachable to probably reachable, and might
659 * affect the status of associated prefixes..
660 */
661 pfxlist_onlink_check();
662 }
663 } else {
664 int llchange;
665
666 /*
667 * Check if the link-layer address has changed or not.
668 */
669 if (!lladdr)
670 llchange = 0;
671 else {
672 if (sdl->sdl_alen) {
673 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen))
674 llchange = 1;
675 else
676 llchange = 0;
677 } else
678 llchange = 1;
679 }
680
681 /*
682 * This is VERY complex. Look at it with care.
683 *
684 * override solicit lladdr llchange action
685 * (L: record lladdr)
686 *
687 * 0 0 n -- (2c)
688 * 0 0 y n (2b) L
689 * 0 0 y y (1) REACHABLE->STALE
690 * 0 1 n -- (2c) *->REACHABLE
691 * 0 1 y n (2b) L *->REACHABLE
692 * 0 1 y y (1) REACHABLE->STALE
693 * 1 0 n -- (2a)
694 * 1 0 y n (2a) L
695 * 1 0 y y (2a) L *->STALE
696 * 1 1 n -- (2a) *->REACHABLE
697 * 1 1 y n (2a) L *->REACHABLE
698 * 1 1 y y (2a) L *->REACHABLE
699 */
700 if (!is_override && (lladdr && llchange)) { /* (1) */
701 /*
702 * If state is REACHABLE, make it STALE.
703 * no other updates should be done.
704 */
705 if (ln->ln_state == ND6_LLINFO_REACHABLE) {
706 ln->ln_state = ND6_LLINFO_STALE;
707 ln->ln_expire = time_second + nd6_gctimer;
708 }
709 goto freeit;
710 } else if (is_override /* (2a) */
711 || (!is_override && (lladdr && !llchange)) /* (2b) */
712 || !lladdr) { /* (2c) */
713 /*
714 * Update link-local address, if any.
715 */
716 if (lladdr) {
717 sdl->sdl_alen = ifp->if_addrlen;
718 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
719 }
720
721 /*
722 * If solicited, make the state REACHABLE.
723 * If not solicited and the link-layer address was
724 * changed, make it STALE.
725 */
726 if (is_solicited) {
727 ln->ln_state = ND6_LLINFO_REACHABLE;
728 ln->ln_byhint = 0;
729 if (ln->ln_expire) {
730 ln->ln_expire = time_second +
731 ND_IFINFO(ifp)->reachable;
732 }
733 } else {
734 if (lladdr && llchange) {
735 ln->ln_state = ND6_LLINFO_STALE;
736 ln->ln_expire = time_second + nd6_gctimer;
737 }
738 }
739 }
740
741 if (ln->ln_router && !is_router) {
742 /*
743 * The peer dropped the router flag.
744 * Remove the sender from the Default Router List and
745 * update the Destination Cache entries.
746 */
747 struct nd_defrouter *dr;
748 struct in6_addr *in6;
749 int s;
750
751 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr;
752
753 /*
754 * Lock to protect the default router list.
755 * XXX: this might be unnecessary, since this function
756 * is only called under the network software interrupt
757 * context. However, we keep it just for safety.
758 */
759 s = splnet();
760 dr = defrouter_lookup(in6, ifp);
761 if (dr)
762 defrtrlist_del(dr);
763 else if (!ip6_forwarding && ip6_accept_rtadv) {
764 /*
765 * Even if the neighbor is not in the default
766 * router list, the neighbor may be used
767 * as a next hop for some destinations
768 * (e.g. redirect case). So we must
769 * call rt6_flush explicitly.
770 */
771 rt6_flush(&ip6->ip6_src, ifp);
772 }
773 splx(s);
774 }
775 ln->ln_router = is_router;
776 }
777 rt->rt_flags &= ~RTF_REJECT;
778 ln->ln_asked = 0;
779 if (ln->ln_hold) {
780 /*
781 * we assume ifp is not a loopback here, so just set the 2nd
782 * argument as the 1st one.
783 */
784 nd6_output(ifp, ifp, ln->ln_hold,
785 (struct sockaddr_in6 *)rt_key(rt), rt);
786 ln->ln_hold = NULL;
787 }
788
789 freeit:
790 m_freem(m);
791 return;
792
793 bad:
794 icmp6stat.icp6s_badna++;
795 m_freem(m);
796 }
797
798 /*
799 * Neighbor advertisement output handling.
800 *
801 * Based on RFC 2461
802 *
803 * the following items are not implemented yet:
804 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
805 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
806 */
807 void
808 nd6_na_output(ifp, daddr6, taddr6, flags, tlladdr, sdl0)
809 struct ifnet *ifp;
810 const struct in6_addr *daddr6, *taddr6;
811 u_long flags;
812 int tlladdr; /* 1 if include target link-layer address */
813 struct sockaddr *sdl0; /* sockaddr_dl (= proxy NA) or NULL */
814 {
815 struct mbuf *m;
816 struct ip6_hdr *ip6;
817 struct nd_neighbor_advert *nd_na;
818 struct in6_ifaddr *ia = NULL;
819 struct ip6_moptions im6o;
820 int icmp6len;
821 int maxlen;
822 caddr_t mac = NULL;
823 struct ifnet *outif = NULL;
824
825 /* estimate the size of message */
826 maxlen = sizeof(*ip6) + sizeof(*nd_na);
827 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
828 if (max_linkhdr + maxlen >= MCLBYTES) {
829 #ifdef DIAGNOSTIC
830 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES "
831 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
832 #endif
833 return;
834 }
835
836 MGETHDR(m, M_DONTWAIT, MT_DATA);
837 if (m && max_linkhdr + maxlen >= MHLEN) {
838 MCLGET(m, M_DONTWAIT);
839 if ((m->m_flags & M_EXT) == 0) {
840 m_free(m);
841 m = NULL;
842 }
843 }
844 if (m == NULL)
845 return;
846 m->m_pkthdr.rcvif = NULL;
847
848 if (IN6_IS_ADDR_MULTICAST(daddr6)) {
849 m->m_flags |= M_MCAST;
850 im6o.im6o_multicast_ifp = ifp;
851 im6o.im6o_multicast_hlim = 255;
852 im6o.im6o_multicast_loop = 0;
853 }
854
855 icmp6len = sizeof(*nd_na);
856 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len;
857 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
858
859 /* fill neighbor advertisement packet */
860 ip6 = mtod(m, struct ip6_hdr *);
861 ip6->ip6_flow = 0;
862 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
863 ip6->ip6_vfc |= IPV6_VERSION;
864 ip6->ip6_nxt = IPPROTO_ICMPV6;
865 ip6->ip6_hlim = 255;
866 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) {
867 /* reply to DAD */
868 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
869 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index);
870 ip6->ip6_dst.s6_addr32[1] = 0;
871 ip6->ip6_dst.s6_addr32[2] = 0;
872 ip6->ip6_dst.s6_addr32[3] = IPV6_ADDR_INT32_ONE;
873 flags &= ~ND_NA_FLAG_SOLICITED;
874 } else
875 ip6->ip6_dst = *daddr6;
876
877 /*
878 * Select a source whose scope is the same as that of the dest.
879 */
880 ia = in6_ifawithifp(ifp, &ip6->ip6_dst);
881 if (ia == NULL) {
882 m_freem(m);
883 return;
884 }
885 ip6->ip6_src = ia->ia_addr.sin6_addr;
886 nd_na = (struct nd_neighbor_advert *)(ip6 + 1);
887 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT;
888 nd_na->nd_na_code = 0;
889 nd_na->nd_na_target = *taddr6;
890 in6_clearscope(&nd_na->nd_na_target); /* XXX */
891
892 /*
893 * "tlladdr" indicates NS's condition for adding tlladdr or not.
894 * see nd6_ns_input() for details.
895 * Basically, if NS packet is sent to unicast/anycast addr,
896 * target lladdr option SHOULD NOT be included.
897 */
898 if (tlladdr) {
899 /*
900 * sdl0 != NULL indicates proxy NA. If we do proxy, use
901 * lladdr in sdl0. If we are not proxying (sending NA for
902 * my address) use lladdr configured for the interface.
903 */
904 if (sdl0 == NULL) {
905 #ifdef DEV_CARP
906 if (ifp->if_carp)
907 mac = carp_macmatch6(ifp->if_carp, m, taddr6);
908 if (mac == NULL)
909 mac = nd6_ifptomac(ifp);
910 #else
911 mac = nd6_ifptomac(ifp);
912 #endif
913 } else if (sdl0->sa_family == AF_LINK) {
914 struct sockaddr_dl *sdl;
915 sdl = (struct sockaddr_dl *)sdl0;
916 if (sdl->sdl_alen == ifp->if_addrlen)
917 mac = LLADDR(sdl);
918 }
919 }
920 if (tlladdr && mac) {
921 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
922 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1);
923
924 /* roundup to 8 bytes alignment! */
925 optlen = (optlen + 7) & ~7;
926
927 m->m_pkthdr.len += optlen;
928 m->m_len += optlen;
929 icmp6len += optlen;
930 bzero((caddr_t)nd_opt, optlen);
931 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
932 nd_opt->nd_opt_len = optlen >> 3;
933 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
934 } else
935 flags &= ~ND_NA_FLAG_OVERRIDE;
936
937 ip6->ip6_plen = htons((u_short)icmp6len);
938 nd_na->nd_na_flags_reserved = flags;
939 nd_na->nd_na_cksum = 0;
940 nd_na->nd_na_cksum =
941 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len);
942
943 ip6_output(m, NULL, NULL, 0, &im6o, &outif, NULL);
944 if (outif) {
945 icmp6_ifstat_inc(outif, ifs6_out_msg);
946 icmp6_ifstat_inc(outif, ifs6_out_neighboradvert);
947 }
948 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++;
949 }
950
951 caddr_t
952 nd6_ifptomac(ifp)
953 struct ifnet *ifp;
954 {
955 switch (ifp->if_type) {
956 case IFT_ARCNET:
957 case IFT_ETHER:
958 case IFT_FDDI:
959 case IFT_IEEE1394:
960 #ifdef IFT_L2VLAN
961 case IFT_L2VLAN:
962 #endif
963 #ifdef IFT_IEEE80211
964 case IFT_IEEE80211:
965 #endif
966 #ifdef IFT_CARP
967 case IFT_CARP:
968 #endif
969 case IFT_ISO88025:
970 return ((caddr_t)(ifp + 1));
971 default:
972 return NULL;
973 }
974 }
975
976 TAILQ_HEAD(dadq_head, dadq);
977 struct dadq {
978 TAILQ_ENTRY(dadq) dad_list;
979 struct ifaddr *dad_ifa;
980 int dad_count; /* max NS to send */
981 int dad_ns_tcount; /* # of trials to send NS */
982 int dad_ns_ocount; /* NS sent so far */
983 int dad_ns_icount;
984 int dad_na_icount;
985 struct callout dad_timer_ch;
986 };
987
988 static struct dadq_head dadq;
989 static int dad_init = 0;
990
991 static struct dadq *
992 nd6_dad_find(ifa)
993 struct ifaddr *ifa;
994 {
995 struct dadq *dp;
996
997 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) {
998 if (dp->dad_ifa == ifa)
999 return dp;
1000 }
1001 return NULL;
1002 }
1003
1004 static void
1005 nd6_dad_starttimer(dp, ticks)
1006 struct dadq *dp;
1007 int ticks;
1008 {
1009
1010 callout_reset(&dp->dad_timer_ch, ticks,
1011 (void (*) __P((void *)))nd6_dad_timer, (void *)dp->dad_ifa);
1012 }
1013
1014 static void
1015 nd6_dad_stoptimer(dp)
1016 struct dadq *dp;
1017 {
1018
1019 callout_stop(&dp->dad_timer_ch);
1020 }
1021
1022 /*
1023 * Start Duplicated Address Detection (DAD) for specified interface address.
1024 */
1025 void
1026 nd6_dad_start(ifa, tick)
1027 struct ifaddr *ifa;
1028 int *tick; /* minimum delay ticks for IFF_UP event */
1029 {
1030 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1031 struct dadq *dp;
1032
1033 if (!dad_init) {
1034 TAILQ_INIT(&dadq);
1035 dad_init++;
1036 }
1037
1038 /*
1039 * If we don't need DAD, don't do it.
1040 * There are several cases:
1041 * - DAD is disabled (ip6_dad_count == 0)
1042 * - the interface address is anycast
1043 */
1044 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
1045 log(LOG_DEBUG,
1046 "nd6_dad_start: called with non-tentative address "
1047 "%s(%s)\n",
1048 ip6_sprintf(&ia->ia_addr.sin6_addr),
1049 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1050 return;
1051 }
1052 if (ia->ia6_flags & IN6_IFF_ANYCAST) {
1053 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1054 return;
1055 }
1056 if (!ip6_dad_count) {
1057 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1058 return;
1059 }
1060 if (!ifa->ifa_ifp)
1061 panic("nd6_dad_start: ifa->ifa_ifp == NULL");
1062 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) {
1063 return;
1064 }
1065 if (nd6_dad_find(ifa) != NULL) {
1066 /* DAD already in progress */
1067 return;
1068 }
1069
1070 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT);
1071 if (dp == NULL) {
1072 log(LOG_ERR, "nd6_dad_start: memory allocation failed for "
1073 "%s(%s)\n",
1074 ip6_sprintf(&ia->ia_addr.sin6_addr),
1075 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1076 return;
1077 }
1078 bzero(dp, sizeof(*dp));
1079 callout_init(&dp->dad_timer_ch, 0);
1080 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list);
1081
1082 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp),
1083 ip6_sprintf(&ia->ia_addr.sin6_addr)));
1084
1085 /*
1086 * Send NS packet for DAD, ip6_dad_count times.
1087 * Note that we must delay the first transmission, if this is the
1088 * first packet to be sent from the interface after interface
1089 * (re)initialization.
1090 */
1091 dp->dad_ifa = ifa;
1092 IFAREF(ifa); /* just for safety */
1093 dp->dad_count = ip6_dad_count;
1094 dp->dad_ns_icount = dp->dad_na_icount = 0;
1095 dp->dad_ns_ocount = dp->dad_ns_tcount = 0;
1096 if (tick == NULL) {
1097 nd6_dad_ns_output(dp, ifa);
1098 nd6_dad_starttimer(dp,
1099 ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1100 } else {
1101 int ntick;
1102
1103 if (*tick == 0)
1104 ntick = arc4random() % (MAX_RTR_SOLICITATION_DELAY * hz);
1105 else
1106 ntick = *tick + arc4random() % (hz / 2);
1107 *tick = ntick;
1108 nd6_dad_starttimer(dp, ntick);
1109 }
1110 }
1111
1112 /*
1113 * terminate DAD unconditionally. used for address removals.
1114 */
1115 void
1116 nd6_dad_stop(ifa)
1117 struct ifaddr *ifa;
1118 {
1119 struct dadq *dp;
1120
1121 if (!dad_init)
1122 return;
1123 dp = nd6_dad_find(ifa);
1124 if (!dp) {
1125 /* DAD wasn't started yet */
1126 return;
1127 }
1128
1129 nd6_dad_stoptimer(dp);
1130
1131 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1132 free(dp, M_IP6NDP);
1133 dp = NULL;
1134 IFAFREE(ifa);
1135 }
1136
1137 static void
1138 nd6_dad_timer(ifa)
1139 struct ifaddr *ifa;
1140 {
1141 int s;
1142 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1143 struct dadq *dp;
1144
1145 s = splnet(); /* XXX */
1146
1147 /* Sanity check */
1148 if (ia == NULL) {
1149 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n");
1150 goto done;
1151 }
1152 dp = nd6_dad_find(ifa);
1153 if (dp == NULL) {
1154 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n");
1155 goto done;
1156 }
1157 if (ia->ia6_flags & IN6_IFF_DUPLICATED) {
1158 log(LOG_ERR, "nd6_dad_timer: called with duplicated address "
1159 "%s(%s)\n",
1160 ip6_sprintf(&ia->ia_addr.sin6_addr),
1161 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1162 goto done;
1163 }
1164 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) {
1165 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address "
1166 "%s(%s)\n",
1167 ip6_sprintf(&ia->ia_addr.sin6_addr),
1168 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1169 goto done;
1170 }
1171
1172 /* timeouted with IFF_{RUNNING,UP} check */
1173 if (dp->dad_ns_tcount > dad_maxtry) {
1174 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n",
1175 if_name(ifa->ifa_ifp)));
1176
1177 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1178 free(dp, M_IP6NDP);
1179 dp = NULL;
1180 IFAFREE(ifa);
1181 goto done;
1182 }
1183
1184 /* Need more checks? */
1185 if (dp->dad_ns_ocount < dp->dad_count) {
1186 /*
1187 * We have more NS to go. Send NS packet for DAD.
1188 */
1189 nd6_dad_ns_output(dp, ifa);
1190 nd6_dad_starttimer(dp,
1191 ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1192 } else {
1193 /*
1194 * We have transmitted sufficient number of DAD packets.
1195 * See what we've got.
1196 */
1197 int duplicate;
1198
1199 duplicate = 0;
1200
1201 if (dp->dad_na_icount) {
1202 /*
1203 * the check is in nd6_dad_na_input(),
1204 * but just in case
1205 */
1206 duplicate++;
1207 }
1208
1209 if (dp->dad_ns_icount) {
1210 #if 0 /* heuristics */
1211 /*
1212 * if
1213 * - we have sent many(?) DAD NS, and
1214 * - the number of NS we sent equals to the
1215 * number of NS we've got, and
1216 * - we've got no NA
1217 * we may have a faulty network card/driver which
1218 * loops back multicasts to myself.
1219 */
1220 if (3 < dp->dad_count
1221 && dp->dad_ns_icount == dp->dad_count
1222 && dp->dad_na_icount == 0) {
1223 log(LOG_INFO, "DAD questionable for %s(%s): "
1224 "network card loops back multicast?\n",
1225 ip6_sprintf(&ia->ia_addr.sin6_addr),
1226 if_name(ifa->ifa_ifp));
1227 /* XXX consider it a duplicate or not? */
1228 /* duplicate++; */
1229 } else {
1230 /* We've seen NS, means DAD has failed. */
1231 duplicate++;
1232 }
1233 #else
1234 /* We've seen NS, means DAD has failed. */
1235 duplicate++;
1236 #endif
1237 }
1238
1239 if (duplicate) {
1240 /* (*dp) will be freed in nd6_dad_duplicated() */
1241 dp = NULL;
1242 nd6_dad_duplicated(ifa);
1243 } else {
1244 /*
1245 * We are done with DAD. No NA came, no NS came.
1246 * duplicated address found.
1247 */
1248 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1249
1250 nd6log((LOG_DEBUG,
1251 "%s: DAD complete for %s - no duplicates found\n",
1252 if_name(ifa->ifa_ifp),
1253 ip6_sprintf(&ia->ia_addr.sin6_addr)));
1254
1255 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1256 free(dp, M_IP6NDP);
1257 dp = NULL;
1258 IFAFREE(ifa);
1259 }
1260 }
1261
1262 done:
1263 splx(s);
1264 }
1265
1266 void
1267 nd6_dad_duplicated(ifa)
1268 struct ifaddr *ifa;
1269 {
1270 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1271 struct dadq *dp;
1272
1273 dp = nd6_dad_find(ifa);
1274 if (dp == NULL) {
1275 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n");
1276 return;
1277 }
1278
1279 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: "
1280 "NS in/out=%d/%d, NA in=%d\n",
1281 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr),
1282 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount);
1283
1284 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1285 ia->ia6_flags |= IN6_IFF_DUPLICATED;
1286
1287 /* We are done with DAD, with duplicated address found. (failure) */
1288 nd6_dad_stoptimer(dp);
1289
1290 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n",
1291 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr));
1292 log(LOG_ERR, "%s: manual intervention required\n",
1293 if_name(ifa->ifa_ifp));
1294
1295 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1296 free(dp, M_IP6NDP);
1297 dp = NULL;
1298 IFAFREE(ifa);
1299 }
1300
1301 static void
1302 nd6_dad_ns_output(dp, ifa)
1303 struct dadq *dp;
1304 struct ifaddr *ifa;
1305 {
1306 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1307 struct ifnet *ifp = ifa->ifa_ifp;
1308
1309 dp->dad_ns_tcount++;
1310 if ((ifp->if_flags & IFF_UP) == 0) {
1311 #if 0
1312 printf("%s: interface down?\n", if_name(ifp));
1313 #endif
1314 return;
1315 }
1316 if ((ifp->if_flags & IFF_RUNNING) == 0) {
1317 #if 0
1318 printf("%s: interface not running?\n", if_name(ifp));
1319 #endif
1320 return;
1321 }
1322
1323 dp->dad_ns_ocount++;
1324 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1);
1325 }
1326
1327 static void
1328 nd6_dad_ns_input(ifa)
1329 struct ifaddr *ifa;
1330 {
1331 struct in6_ifaddr *ia;
1332 struct ifnet *ifp;
1333 const struct in6_addr *taddr6;
1334 struct dadq *dp;
1335 int duplicate;
1336
1337 if (!ifa)
1338 panic("ifa == NULL in nd6_dad_ns_input");
1339
1340 ia = (struct in6_ifaddr *)ifa;
1341 ifp = ifa->ifa_ifp;
1342 taddr6 = &ia->ia_addr.sin6_addr;
1343 duplicate = 0;
1344 dp = nd6_dad_find(ifa);
1345
1346 /* Quickhack - completely ignore DAD NS packets */
1347 if (dad_ignore_ns) {
1348 nd6log((LOG_INFO,
1349 "nd6_dad_ns_input: ignoring DAD NS packet for "
1350 "address %s(%s)\n", ip6_sprintf(taddr6),
1351 if_name(ifa->ifa_ifp)));
1352 return;
1353 }
1354
1355 /*
1356 * if I'm yet to start DAD, someone else started using this address
1357 * first. I have a duplicate and you win.
1358 */
1359 if (!dp || dp->dad_ns_ocount == 0)
1360 duplicate++;
1361
1362 /* XXX more checks for loopback situation - see nd6_dad_timer too */
1363
1364 if (duplicate) {
1365 dp = NULL; /* will be freed in nd6_dad_duplicated() */
1366 nd6_dad_duplicated(ifa);
1367 } else {
1368 /*
1369 * not sure if I got a duplicate.
1370 * increment ns count and see what happens.
1371 */
1372 if (dp)
1373 dp->dad_ns_icount++;
1374 }
1375 }
1376
1377 static void
1378 nd6_dad_na_input(ifa)
1379 struct ifaddr *ifa;
1380 {
1381 struct dadq *dp;
1382
1383 if (!ifa)
1384 panic("ifa == NULL in nd6_dad_na_input");
1385
1386 dp = nd6_dad_find(ifa);
1387 if (dp)
1388 dp->dad_na_icount++;
1389
1390 /* remove the address. */
1391 nd6_dad_duplicated(ifa);
1392 }
Cache object: cb35369c49f8c9352124ddef040954fd
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