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: releng/7.4/sys/netinet6/nd6_nbr.c 215996 2010-11-28 13:01:10Z bz $");
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_LOCKED(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 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 bzero(&ro, sizeof(ro));
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 error = in6_selectsrc(&dst_sa, NULL,
477 NULL, &ro, NULL, NULL, &src_in);
478 if (error) {
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 src = &src_in;
488 }
489 } else {
490 /*
491 * Source address for DAD packet must always be IPv6
492 * unspecified address. (0::0)
493 * We actually don't have to 0-clear the address (we did it
494 * above), but we do so here explicitly to make the intention
495 * clearer.
496 */
497 bzero(&src_in, sizeof(src_in));
498 src = &src_in;
499 }
500 ip6->ip6_src = *src;
501 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1);
502 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT;
503 nd_ns->nd_ns_code = 0;
504 nd_ns->nd_ns_reserved = 0;
505 nd_ns->nd_ns_target = *taddr6;
506 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */
507
508 /*
509 * Add source link-layer address option.
510 *
511 * spec implementation
512 * --- ---
513 * DAD packet MUST NOT do not add the option
514 * there's no link layer address:
515 * impossible do not add the option
516 * there's link layer address:
517 * Multicast NS MUST add one add the option
518 * Unicast NS SHOULD add one add the option
519 */
520 if (!dad && (mac = nd6_ifptomac(ifp))) {
521 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
522 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
523 /* 8 byte alignments... */
524 optlen = (optlen + 7) & ~7;
525
526 m->m_pkthdr.len += optlen;
527 m->m_len += optlen;
528 icmp6len += optlen;
529 bzero((caddr_t)nd_opt, optlen);
530 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR;
531 nd_opt->nd_opt_len = optlen >> 3;
532 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
533 }
534
535 ip6->ip6_plen = htons((u_short)icmp6len);
536 nd_ns->nd_ns_cksum = 0;
537 nd_ns->nd_ns_cksum =
538 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len);
539
540 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL);
541 icmp6_ifstat_inc(ifp, ifs6_out_msg);
542 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit);
543 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++;
544
545 if (ro.ro_rt) { /* we don't cache this route. */
546 RTFREE(ro.ro_rt);
547 }
548 return;
549
550 bad:
551 if (ro.ro_rt) {
552 RTFREE(ro.ro_rt);
553 }
554 m_freem(m);
555 return;
556 }
557
558 /*
559 * Neighbor advertisement input handling.
560 *
561 * Based on RFC 2461
562 * Based on RFC 2462 (duplicate address detection)
563 *
564 * the following items are not implemented yet:
565 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
566 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
567 */
568 void
569 nd6_na_input(struct mbuf *m, int off, int icmp6len)
570 {
571 struct ifnet *ifp = m->m_pkthdr.rcvif;
572 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
573 struct nd_neighbor_advert *nd_na;
574 struct in6_addr daddr6 = ip6->ip6_dst;
575 struct in6_addr taddr6;
576 int flags;
577 int is_router;
578 int is_solicited;
579 int is_override;
580 char *lladdr = NULL;
581 int lladdrlen = 0;
582 struct ifaddr *ifa;
583 struct llinfo_nd6 *ln;
584 struct rtentry *rt;
585 struct sockaddr_dl *sdl;
586 union nd_opts ndopts;
587 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
588
589 if (ip6->ip6_hlim != 255) {
590 nd6log((LOG_ERR,
591 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n",
592 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
593 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
594 goto bad;
595 }
596
597 #ifndef PULLDOWN_TEST
598 IP6_EXTHDR_CHECK(m, off, icmp6len,);
599 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off);
600 #else
601 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len);
602 if (nd_na == NULL) {
603 icmp6stat.icp6s_tooshort++;
604 return;
605 }
606 #endif
607
608 flags = nd_na->nd_na_flags_reserved;
609 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0);
610 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0);
611 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0);
612
613 taddr6 = nd_na->nd_na_target;
614 if (in6_setscope(&taddr6, ifp, NULL))
615 goto bad; /* XXX: impossible */
616
617 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
618 nd6log((LOG_ERR,
619 "nd6_na_input: invalid target address %s\n",
620 ip6_sprintf(ip6bufs, &taddr6)));
621 goto bad;
622 }
623 if (IN6_IS_ADDR_MULTICAST(&daddr6))
624 if (is_solicited) {
625 nd6log((LOG_ERR,
626 "nd6_na_input: a solicited adv is multicasted\n"));
627 goto bad;
628 }
629
630 icmp6len -= sizeof(*nd_na);
631 nd6_option_init(nd_na + 1, icmp6len, &ndopts);
632 if (nd6_options(&ndopts) < 0) {
633 nd6log((LOG_INFO,
634 "nd6_na_input: invalid ND option, ignored\n"));
635 /* nd6_options have incremented stats */
636 goto freeit;
637 }
638
639 if (ndopts.nd_opts_tgt_lladdr) {
640 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
641 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
642 }
643
644 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
645
646 /*
647 * Target address matches one of my interface address.
648 *
649 * If my address is tentative, this means that there's somebody
650 * already using the same address as mine. This indicates DAD failure.
651 * This is defined in RFC 2462.
652 *
653 * Otherwise, process as defined in RFC 2461.
654 */
655 if (ifa
656 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) {
657 nd6_dad_na_input(ifa);
658 goto freeit;
659 }
660
661 /* Just for safety, maybe unnecessary. */
662 if (ifa) {
663 log(LOG_ERR,
664 "nd6_na_input: duplicate IP6 address %s\n",
665 ip6_sprintf(ip6bufs, &taddr6));
666 goto freeit;
667 }
668
669 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
670 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s "
671 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6),
672 ifp->if_addrlen, lladdrlen - 2));
673 goto bad;
674 }
675
676 /*
677 * If no neighbor cache entry is found, NA SHOULD silently be
678 * discarded.
679 */
680 rt = nd6_lookup(&taddr6, 0, ifp);
681 if ((rt == NULL) ||
682 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) ||
683 ((sdl = SDL(rt->rt_gateway)) == NULL))
684 goto freeit;
685
686 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
687 /*
688 * If the link-layer has address, and no lladdr option came,
689 * discard the packet.
690 */
691 if (ifp->if_addrlen && lladdr == NULL)
692 goto freeit;
693
694 /*
695 * Record link-layer address, and update the state.
696 */
697 sdl->sdl_alen = ifp->if_addrlen;
698 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
699 if (is_solicited) {
700 ln->ln_state = ND6_LLINFO_REACHABLE;
701 ln->ln_byhint = 0;
702 if (!ND6_LLINFO_PERMANENT(ln)) {
703 nd6_llinfo_settimer(ln,
704 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz);
705 }
706 } else {
707 ln->ln_state = ND6_LLINFO_STALE;
708 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz);
709 }
710 if ((ln->ln_router = is_router) != 0) {
711 /*
712 * This means a router's state has changed from
713 * non-reachable to probably reachable, and might
714 * affect the status of associated prefixes..
715 */
716 pfxlist_onlink_check();
717 }
718 } else {
719 int llchange;
720
721 /*
722 * Check if the link-layer address has changed or not.
723 */
724 if (lladdr == NULL)
725 llchange = 0;
726 else {
727 if (sdl->sdl_alen) {
728 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen))
729 llchange = 1;
730 else
731 llchange = 0;
732 } else
733 llchange = 1;
734 }
735
736 /*
737 * This is VERY complex. Look at it with care.
738 *
739 * override solicit lladdr llchange action
740 * (L: record lladdr)
741 *
742 * 0 0 n -- (2c)
743 * 0 0 y n (2b) L
744 * 0 0 y y (1) REACHABLE->STALE
745 * 0 1 n -- (2c) *->REACHABLE
746 * 0 1 y n (2b) L *->REACHABLE
747 * 0 1 y y (1) REACHABLE->STALE
748 * 1 0 n -- (2a)
749 * 1 0 y n (2a) L
750 * 1 0 y y (2a) L *->STALE
751 * 1 1 n -- (2a) *->REACHABLE
752 * 1 1 y n (2a) L *->REACHABLE
753 * 1 1 y y (2a) L *->REACHABLE
754 */
755 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */
756 /*
757 * If state is REACHABLE, make it STALE.
758 * no other updates should be done.
759 */
760 if (ln->ln_state == ND6_LLINFO_REACHABLE) {
761 ln->ln_state = ND6_LLINFO_STALE;
762 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz);
763 }
764 goto freeit;
765 } else if (is_override /* (2a) */
766 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */
767 || lladdr == NULL) { /* (2c) */
768 /*
769 * Update link-local address, if any.
770 */
771 if (lladdr != NULL) {
772 sdl->sdl_alen = ifp->if_addrlen;
773 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
774 }
775
776 /*
777 * If solicited, make the state REACHABLE.
778 * If not solicited and the link-layer address was
779 * changed, make it STALE.
780 */
781 if (is_solicited) {
782 ln->ln_state = ND6_LLINFO_REACHABLE;
783 ln->ln_byhint = 0;
784 if (!ND6_LLINFO_PERMANENT(ln)) {
785 nd6_llinfo_settimer(ln,
786 (long)ND_IFINFO(ifp)->reachable * hz);
787 }
788 } else {
789 if (lladdr != NULL && llchange) {
790 ln->ln_state = ND6_LLINFO_STALE;
791 nd6_llinfo_settimer(ln,
792 (long)nd6_gctimer * hz);
793 }
794 }
795 }
796
797 if (ln->ln_router && !is_router) {
798 /*
799 * The peer dropped the router flag.
800 * Remove the sender from the Default Router List and
801 * update the Destination Cache entries.
802 */
803 struct nd_defrouter *dr;
804 struct in6_addr *in6;
805 int s;
806
807 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr;
808
809 /*
810 * Lock to protect the default router list.
811 * XXX: this might be unnecessary, since this function
812 * is only called under the network software interrupt
813 * context. However, we keep it just for safety.
814 */
815 s = splnet();
816 dr = defrouter_lookup(in6, ifp);
817 if (dr)
818 defrtrlist_del(dr);
819 else if (!ip6_forwarding) {
820 /*
821 * Even if the neighbor is not in the default
822 * router list, the neighbor may be used
823 * as a next hop for some destinations
824 * (e.g. redirect case). So we must
825 * call rt6_flush explicitly.
826 */
827 rt6_flush(&ip6->ip6_src, ifp);
828 }
829 splx(s);
830 }
831 ln->ln_router = is_router;
832 }
833 rt->rt_flags &= ~RTF_REJECT;
834 ln->ln_asked = 0;
835 if (ln->ln_hold) {
836 struct mbuf *m_hold, *m_hold_next;
837
838 /*
839 * reset the ln_hold in advance, to explicitly
840 * prevent a ln_hold lookup in nd6_output()
841 * (wouldn't happen, though...)
842 */
843 for (m_hold = ln->ln_hold;
844 m_hold; m_hold = m_hold_next) {
845 m_hold_next = m_hold->m_nextpkt;
846 m_hold->m_nextpkt = NULL;
847 /*
848 * we assume ifp is not a loopback here, so just set
849 * the 2nd argument as the 1st one.
850 */
851 nd6_output(ifp, ifp, m_hold,
852 (struct sockaddr_in6 *)rt_key(rt), rt);
853 }
854 ln->ln_hold = NULL;
855 }
856
857 freeit:
858 m_freem(m);
859 return;
860
861 bad:
862 icmp6stat.icp6s_badna++;
863 m_freem(m);
864 }
865
866 /*
867 * Neighbor advertisement output handling.
868 *
869 * Based on RFC 2461
870 *
871 * the following items are not implemented yet:
872 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
873 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
874 *
875 * tlladdr - 1 if include target link-layer address
876 * sdl0 - sockaddr_dl (= proxy NA) or NULL
877 */
878 void
879 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0,
880 const struct in6_addr *taddr6, u_long flags, int tlladdr,
881 struct sockaddr *sdl0)
882 {
883 struct mbuf *m;
884 struct ip6_hdr *ip6;
885 struct nd_neighbor_advert *nd_na;
886 struct ip6_moptions im6o;
887 struct in6_addr src, daddr6;
888 struct sockaddr_in6 dst_sa;
889 int icmp6len, maxlen, error;
890 caddr_t mac = NULL;
891 struct route_in6 ro;
892
893 bzero(&ro, sizeof(ro));
894
895 daddr6 = *daddr6_0; /* make a local copy for modification */
896
897 /* estimate the size of message */
898 maxlen = sizeof(*ip6) + sizeof(*nd_na);
899 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
900 if (max_linkhdr + maxlen >= MCLBYTES) {
901 #ifdef DIAGNOSTIC
902 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES "
903 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
904 #endif
905 return;
906 }
907
908 MGETHDR(m, M_DONTWAIT, MT_DATA);
909 if (m && max_linkhdr + maxlen >= MHLEN) {
910 MCLGET(m, M_DONTWAIT);
911 if ((m->m_flags & M_EXT) == 0) {
912 m_free(m);
913 m = NULL;
914 }
915 }
916 if (m == NULL)
917 return;
918 m->m_pkthdr.rcvif = NULL;
919
920 if (IN6_IS_ADDR_MULTICAST(&daddr6)) {
921 m->m_flags |= M_MCAST;
922 im6o.im6o_multicast_ifp = ifp;
923 im6o.im6o_multicast_hlim = 255;
924 im6o.im6o_multicast_loop = 0;
925 }
926
927 icmp6len = sizeof(*nd_na);
928 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len;
929 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
930
931 /* fill neighbor advertisement packet */
932 ip6 = mtod(m, struct ip6_hdr *);
933 ip6->ip6_flow = 0;
934 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
935 ip6->ip6_vfc |= IPV6_VERSION;
936 ip6->ip6_nxt = IPPROTO_ICMPV6;
937 ip6->ip6_hlim = 255;
938 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) {
939 /* reply to DAD */
940 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
941 daddr6.s6_addr16[1] = 0;
942 daddr6.s6_addr32[1] = 0;
943 daddr6.s6_addr32[2] = 0;
944 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE;
945 if (in6_setscope(&daddr6, ifp, NULL))
946 goto bad;
947
948 flags &= ~ND_NA_FLAG_SOLICITED;
949 }
950 ip6->ip6_dst = daddr6;
951 bzero(&dst_sa, sizeof(struct sockaddr_in6));
952 dst_sa.sin6_family = AF_INET6;
953 dst_sa.sin6_len = sizeof(struct sockaddr_in6);
954 dst_sa.sin6_addr = daddr6;
955
956 /*
957 * Select a source whose scope is the same as that of the dest.
958 */
959 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa));
960 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &src);
961 if (error) {
962 char ip6buf[INET6_ADDRSTRLEN];
963 nd6log((LOG_DEBUG, "nd6_na_output: source can't be "
964 "determined: dst=%s, error=%d\n",
965 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error));
966 goto bad;
967 }
968 ip6->ip6_src = src;
969 nd_na = (struct nd_neighbor_advert *)(ip6 + 1);
970 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT;
971 nd_na->nd_na_code = 0;
972 nd_na->nd_na_target = *taddr6;
973 in6_clearscope(&nd_na->nd_na_target); /* XXX */
974
975 /*
976 * "tlladdr" indicates NS's condition for adding tlladdr or not.
977 * see nd6_ns_input() for details.
978 * Basically, if NS packet is sent to unicast/anycast addr,
979 * target lladdr option SHOULD NOT be included.
980 */
981 if (tlladdr) {
982 /*
983 * sdl0 != NULL indicates proxy NA. If we do proxy, use
984 * lladdr in sdl0. If we are not proxying (sending NA for
985 * my address) use lladdr configured for the interface.
986 */
987 if (sdl0 == NULL) {
988 #ifdef DEV_CARP
989 if (ifp->if_carp)
990 mac = carp_macmatch6(ifp->if_carp, m, taddr6);
991 if (mac == NULL)
992 mac = nd6_ifptomac(ifp);
993 #else
994 mac = nd6_ifptomac(ifp);
995 #endif
996 } else if (sdl0->sa_family == AF_LINK) {
997 struct sockaddr_dl *sdl;
998 sdl = (struct sockaddr_dl *)sdl0;
999 if (sdl->sdl_alen == ifp->if_addrlen)
1000 mac = LLADDR(sdl);
1001 }
1002 }
1003 if (tlladdr && mac) {
1004 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
1005 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1);
1006
1007 /* roundup to 8 bytes alignment! */
1008 optlen = (optlen + 7) & ~7;
1009
1010 m->m_pkthdr.len += optlen;
1011 m->m_len += optlen;
1012 icmp6len += optlen;
1013 bzero((caddr_t)nd_opt, optlen);
1014 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
1015 nd_opt->nd_opt_len = optlen >> 3;
1016 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
1017 } else
1018 flags &= ~ND_NA_FLAG_OVERRIDE;
1019
1020 ip6->ip6_plen = htons((u_short)icmp6len);
1021 nd_na->nd_na_flags_reserved = flags;
1022 nd_na->nd_na_cksum = 0;
1023 nd_na->nd_na_cksum =
1024 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len);
1025
1026 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL);
1027 icmp6_ifstat_inc(ifp, ifs6_out_msg);
1028 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert);
1029 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++;
1030
1031 if (ro.ro_rt) { /* we don't cache this route. */
1032 RTFREE(ro.ro_rt);
1033 }
1034 return;
1035
1036 bad:
1037 if (ro.ro_rt) {
1038 RTFREE(ro.ro_rt);
1039 }
1040 m_freem(m);
1041 return;
1042 }
1043
1044 caddr_t
1045 nd6_ifptomac(struct ifnet *ifp)
1046 {
1047 switch (ifp->if_type) {
1048 case IFT_ARCNET:
1049 case IFT_ETHER:
1050 case IFT_FDDI:
1051 case IFT_IEEE1394:
1052 #ifdef IFT_L2VLAN
1053 case IFT_L2VLAN:
1054 #endif
1055 #ifdef IFT_IEEE80211
1056 case IFT_IEEE80211:
1057 #endif
1058 #ifdef IFT_CARP
1059 case IFT_CARP:
1060 #endif
1061 case IFT_BRIDGE:
1062 case IFT_ISO88025:
1063 return IF_LLADDR(ifp);
1064 default:
1065 return NULL;
1066 }
1067 }
1068
1069 TAILQ_HEAD(dadq_head, dadq);
1070 struct dadq {
1071 TAILQ_ENTRY(dadq) dad_list;
1072 struct ifaddr *dad_ifa;
1073 int dad_count; /* max NS to send */
1074 int dad_ns_tcount; /* # of trials to send NS */
1075 int dad_ns_ocount; /* NS sent so far */
1076 int dad_ns_icount;
1077 int dad_na_icount;
1078 struct callout dad_timer_ch;
1079 };
1080
1081 static struct dadq_head dadq;
1082 static int dad_init = 0;
1083
1084 static struct dadq *
1085 nd6_dad_find(struct ifaddr *ifa)
1086 {
1087 struct dadq *dp;
1088
1089 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) {
1090 if (dp->dad_ifa == ifa)
1091 return dp;
1092 }
1093 return NULL;
1094 }
1095
1096 static void
1097 nd6_dad_starttimer(struct dadq *dp, int ticks)
1098 {
1099
1100 callout_reset(&dp->dad_timer_ch, ticks,
1101 (void (*)(void *))nd6_dad_timer, (void *)dp->dad_ifa);
1102 }
1103
1104 static void
1105 nd6_dad_stoptimer(struct dadq *dp)
1106 {
1107
1108 callout_stop(&dp->dad_timer_ch);
1109 }
1110
1111 /*
1112 * Start Duplicate Address Detection (DAD) for specified interface address.
1113 */
1114 void
1115 nd6_dad_start(struct ifaddr *ifa, int delay)
1116 {
1117 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1118 struct dadq *dp;
1119 char ip6buf[INET6_ADDRSTRLEN];
1120
1121 if (!dad_init) {
1122 TAILQ_INIT(&dadq);
1123 dad_init++;
1124 }
1125
1126 /*
1127 * If we don't need DAD, don't do it.
1128 * There are several cases:
1129 * - DAD is disabled (ip6_dad_count == 0)
1130 * - the interface address is anycast
1131 */
1132 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
1133 log(LOG_DEBUG,
1134 "nd6_dad_start: called with non-tentative address "
1135 "%s(%s)\n",
1136 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1137 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1138 return;
1139 }
1140 if (ia->ia6_flags & IN6_IFF_ANYCAST) {
1141 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1142 return;
1143 }
1144 if (!ip6_dad_count) {
1145 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1146 return;
1147 }
1148 if (ifa->ifa_ifp == NULL)
1149 panic("nd6_dad_start: ifa->ifa_ifp == NULL");
1150 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) {
1151 return;
1152 }
1153 if (nd6_dad_find(ifa) != NULL) {
1154 /* DAD already in progress */
1155 return;
1156 }
1157
1158 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT);
1159 if (dp == NULL) {
1160 log(LOG_ERR, "nd6_dad_start: memory allocation failed for "
1161 "%s(%s)\n",
1162 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1163 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1164 return;
1165 }
1166 bzero(dp, sizeof(*dp));
1167 callout_init(&dp->dad_timer_ch, 0);
1168 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list);
1169
1170 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp),
1171 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1172
1173 /*
1174 * Send NS packet for DAD, ip6_dad_count times.
1175 * Note that we must delay the first transmission, if this is the
1176 * first packet to be sent from the interface after interface
1177 * (re)initialization.
1178 */
1179 dp->dad_ifa = ifa;
1180 IFAREF(ifa); /* just for safety */
1181 dp->dad_count = ip6_dad_count;
1182 dp->dad_ns_icount = dp->dad_na_icount = 0;
1183 dp->dad_ns_ocount = dp->dad_ns_tcount = 0;
1184 if (delay == 0) {
1185 nd6_dad_ns_output(dp, ifa);
1186 nd6_dad_starttimer(dp,
1187 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1188 } else {
1189 nd6_dad_starttimer(dp, delay);
1190 }
1191 }
1192
1193 /*
1194 * terminate DAD unconditionally. used for address removals.
1195 */
1196 void
1197 nd6_dad_stop(struct ifaddr *ifa)
1198 {
1199 struct dadq *dp;
1200
1201 if (!dad_init)
1202 return;
1203 dp = nd6_dad_find(ifa);
1204 if (!dp) {
1205 /* DAD wasn't started yet */
1206 return;
1207 }
1208
1209 nd6_dad_stoptimer(dp);
1210
1211 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1212 free(dp, M_IP6NDP);
1213 dp = NULL;
1214 IFAFREE(ifa);
1215 }
1216
1217 static void
1218 nd6_dad_timer(struct ifaddr *ifa)
1219 {
1220 int s;
1221 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1222 struct dadq *dp;
1223 char ip6buf[INET6_ADDRSTRLEN];
1224
1225 s = splnet(); /* XXX */
1226
1227 /* Sanity check */
1228 if (ia == NULL) {
1229 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n");
1230 goto done;
1231 }
1232 dp = nd6_dad_find(ifa);
1233 if (dp == NULL) {
1234 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n");
1235 goto done;
1236 }
1237 if (ia->ia6_flags & IN6_IFF_DUPLICATED) {
1238 log(LOG_ERR, "nd6_dad_timer: called with duplicated address "
1239 "%s(%s)\n",
1240 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1241 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1242 goto done;
1243 }
1244 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) {
1245 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address "
1246 "%s(%s)\n",
1247 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1248 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1249 goto done;
1250 }
1251
1252 /* timeouted with IFF_{RUNNING,UP} check */
1253 if (dp->dad_ns_tcount > dad_maxtry) {
1254 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n",
1255 if_name(ifa->ifa_ifp)));
1256
1257 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1258 free(dp, M_IP6NDP);
1259 dp = NULL;
1260 IFAFREE(ifa);
1261 goto done;
1262 }
1263
1264 /* Need more checks? */
1265 if (dp->dad_ns_ocount < dp->dad_count) {
1266 /*
1267 * We have more NS to go. Send NS packet for DAD.
1268 */
1269 nd6_dad_ns_output(dp, ifa);
1270 nd6_dad_starttimer(dp,
1271 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1272 } else {
1273 /*
1274 * We have transmitted sufficient number of DAD packets.
1275 * See what we've got.
1276 */
1277 int duplicate;
1278
1279 duplicate = 0;
1280
1281 if (dp->dad_na_icount) {
1282 /*
1283 * the check is in nd6_dad_na_input(),
1284 * but just in case
1285 */
1286 duplicate++;
1287 }
1288
1289 if (dp->dad_ns_icount) {
1290 /* We've seen NS, means DAD has failed. */
1291 duplicate++;
1292 }
1293
1294 if (duplicate) {
1295 /* (*dp) will be freed in nd6_dad_duplicated() */
1296 dp = NULL;
1297 nd6_dad_duplicated(ifa);
1298 } else {
1299 /*
1300 * We are done with DAD. No NA came, no NS came.
1301 * No duplicate address found.
1302 */
1303 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1304
1305 nd6log((LOG_DEBUG,
1306 "%s: DAD complete for %s - no duplicates found\n",
1307 if_name(ifa->ifa_ifp),
1308 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1309
1310 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1311 free(dp, M_IP6NDP);
1312 dp = NULL;
1313 IFAFREE(ifa);
1314 }
1315 }
1316
1317 done:
1318 splx(s);
1319 }
1320
1321 void
1322 nd6_dad_duplicated(struct ifaddr *ifa)
1323 {
1324 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1325 struct ifnet *ifp;
1326 struct dadq *dp;
1327 char ip6buf[INET6_ADDRSTRLEN];
1328
1329 dp = nd6_dad_find(ifa);
1330 if (dp == NULL) {
1331 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n");
1332 return;
1333 }
1334
1335 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: "
1336 "NS in/out=%d/%d, NA in=%d\n",
1337 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1338 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount);
1339
1340 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1341 ia->ia6_flags |= IN6_IFF_DUPLICATED;
1342
1343 /* We are done with DAD, with duplicate address found. (failure) */
1344 nd6_dad_stoptimer(dp);
1345
1346 ifp = ifa->ifa_ifp;
1347 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n",
1348 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr));
1349 log(LOG_ERR, "%s: manual intervention required\n",
1350 if_name(ifp));
1351
1352 /*
1353 * If the address is a link-local address formed from an interface
1354 * identifier based on the hardware address which is supposed to be
1355 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP
1356 * operation on the interface SHOULD be disabled.
1357 * [rfc2462bis-03 Section 5.4.5]
1358 */
1359 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) {
1360 struct in6_addr in6;
1361
1362 /*
1363 * To avoid over-reaction, we only apply this logic when we are
1364 * very sure that hardware addresses are supposed to be unique.
1365 */
1366 switch (ifp->if_type) {
1367 case IFT_ETHER:
1368 case IFT_FDDI:
1369 case IFT_ATM:
1370 case IFT_IEEE1394:
1371 #ifdef IFT_IEEE80211
1372 case IFT_IEEE80211:
1373 #endif
1374 in6 = ia->ia_addr.sin6_addr;
1375 if (in6_get_hw_ifid(ifp, &in6) == 0 &&
1376 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) {
1377 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED;
1378 log(LOG_ERR, "%s: possible hardware address "
1379 "duplication detected, disable IPv6\n",
1380 if_name(ifp));
1381 }
1382 break;
1383 }
1384 }
1385
1386 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list);
1387 free(dp, M_IP6NDP);
1388 dp = NULL;
1389 IFAFREE(ifa);
1390 }
1391
1392 static void
1393 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa)
1394 {
1395 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1396 struct ifnet *ifp = ifa->ifa_ifp;
1397
1398 dp->dad_ns_tcount++;
1399 if ((ifp->if_flags & IFF_UP) == 0) {
1400 return;
1401 }
1402 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
1403 return;
1404 }
1405
1406 dp->dad_ns_ocount++;
1407 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1);
1408 }
1409
1410 static void
1411 nd6_dad_ns_input(struct ifaddr *ifa)
1412 {
1413 struct in6_ifaddr *ia;
1414 struct ifnet *ifp;
1415 const struct in6_addr *taddr6;
1416 struct dadq *dp;
1417 int duplicate;
1418
1419 if (ifa == NULL)
1420 panic("ifa == NULL in nd6_dad_ns_input");
1421
1422 ia = (struct in6_ifaddr *)ifa;
1423 ifp = ifa->ifa_ifp;
1424 taddr6 = &ia->ia_addr.sin6_addr;
1425 duplicate = 0;
1426 dp = nd6_dad_find(ifa);
1427
1428 /* Quickhack - completely ignore DAD NS packets */
1429 if (dad_ignore_ns) {
1430 char ip6buf[INET6_ADDRSTRLEN];
1431 nd6log((LOG_INFO,
1432 "nd6_dad_ns_input: ignoring DAD NS packet for "
1433 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6),
1434 if_name(ifa->ifa_ifp)));
1435 return;
1436 }
1437
1438 /*
1439 * if I'm yet to start DAD, someone else started using this address
1440 * first. I have a duplicate and you win.
1441 */
1442 if (dp == NULL || dp->dad_ns_ocount == 0)
1443 duplicate++;
1444
1445 /* XXX more checks for loopback situation - see nd6_dad_timer too */
1446
1447 if (duplicate) {
1448 dp = NULL; /* will be freed in nd6_dad_duplicated() */
1449 nd6_dad_duplicated(ifa);
1450 } else {
1451 /*
1452 * not sure if I got a duplicate.
1453 * increment ns count and see what happens.
1454 */
1455 if (dp)
1456 dp->dad_ns_icount++;
1457 }
1458 }
1459
1460 static void
1461 nd6_dad_na_input(struct ifaddr *ifa)
1462 {
1463 struct dadq *dp;
1464
1465 if (ifa == NULL)
1466 panic("ifa == NULL in nd6_dad_na_input");
1467
1468 dp = nd6_dad_find(ifa);
1469 if (dp)
1470 dp->dad_na_icount++;
1471
1472 /* remove the address. */
1473 nd6_dad_duplicated(ifa);
1474 }
Cache object: 43b1527df5c5dcd046df6f3a359af476
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