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/8.0/sys/netinet6/nd6_nbr.c 196019 2009-08-01 19:26:27Z rwatson $");
34
35 #include "opt_inet.h"
36 #include "opt_inet6.h"
37 #include "opt_ipsec.h"
38 #include "opt_carp.h"
39 #include "opt_mpath.h"
40
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/malloc.h>
44 #include <sys/lock.h>
45 #include <sys/rwlock.h>
46 #include <sys/mbuf.h>
47 #include <sys/socket.h>
48 #include <sys/sockio.h>
49 #include <sys/time.h>
50 #include <sys/kernel.h>
51 #include <sys/errno.h>
52 #include <sys/syslog.h>
53 #include <sys/queue.h>
54 #include <sys/callout.h>
55
56 #include <net/if.h>
57 #include <net/if_types.h>
58 #include <net/if_dl.h>
59 #include <net/if_var.h>
60 #include <net/route.h>
61 #ifdef RADIX_MPATH
62 #include <net/radix_mpath.h>
63 #endif
64
65 #include <netinet/in.h>
66 #include <netinet/in_var.h>
67 #include <net/if_llatbl.h>
68 #define L3_ADDR_SIN6(le) ((struct sockaddr_in6 *) L3_ADDR(le))
69 #include <netinet6/in6_var.h>
70 #include <netinet6/in6_ifattach.h>
71 #include <netinet/ip6.h>
72 #include <netinet6/ip6_var.h>
73 #include <netinet6/scope6_var.h>
74 #include <netinet6/nd6.h>
75 #include <netinet/icmp6.h>
76
77 #ifdef DEV_CARP
78 #include <netinet/ip_carp.h>
79 #endif
80
81 #define SDL(s) ((struct sockaddr_dl *)s)
82
83 struct dadq;
84 static struct dadq *nd6_dad_find(struct ifaddr *);
85 static void nd6_dad_starttimer(struct dadq *, int);
86 static void nd6_dad_stoptimer(struct dadq *);
87 static void nd6_dad_timer(struct dadq *);
88 static void nd6_dad_ns_output(struct dadq *, struct ifaddr *);
89 static void nd6_dad_ns_input(struct ifaddr *);
90 static void nd6_dad_na_input(struct ifaddr *);
91
92 VNET_DEFINE(int, dad_ignore_ns);
93 VNET_DEFINE(int, dad_maxtry);
94
95 #define V_dad_ignore_ns VNET(dad_ignore_ns)
96 #define V_dad_maxtry VNET(dad_maxtry)
97
98 /*
99 * Input a Neighbor Solicitation Message.
100 *
101 * Based on RFC 2461
102 * Based on RFC 2462 (duplicate address detection)
103 */
104 void
105 nd6_ns_input(struct mbuf *m, int off, int icmp6len)
106 {
107 struct ifnet *ifp = m->m_pkthdr.rcvif;
108 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
109 struct nd_neighbor_solicit *nd_ns;
110 struct in6_addr saddr6 = ip6->ip6_src;
111 struct in6_addr daddr6 = ip6->ip6_dst;
112 struct in6_addr taddr6;
113 struct in6_addr myaddr6;
114 char *lladdr = NULL;
115 struct ifaddr *ifa = NULL;
116 int lladdrlen = 0;
117 int anycast = 0, proxy = 0, tentative = 0;
118 int tlladdr;
119 union nd_opts ndopts;
120 struct sockaddr_dl *proxydl = NULL;
121 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
122
123 #ifndef PULLDOWN_TEST
124 IP6_EXTHDR_CHECK(m, off, icmp6len,);
125 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off);
126 #else
127 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len);
128 if (nd_ns == NULL) {
129 ICMP6STAT_INC(icp6s_tooshort);
130 return;
131 }
132 #endif
133 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */
134 taddr6 = nd_ns->nd_ns_target;
135 if (in6_setscope(&taddr6, ifp, NULL) != 0)
136 goto bad;
137
138 if (ip6->ip6_hlim != 255) {
139 nd6log((LOG_ERR,
140 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n",
141 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
142 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
143 goto bad;
144 }
145
146 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
147 /* dst has to be a solicited node multicast address. */
148 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL &&
149 /* don't check ifindex portion */
150 daddr6.s6_addr32[1] == 0 &&
151 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE &&
152 daddr6.s6_addr8[12] == 0xff) {
153 ; /* good */
154 } else {
155 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
156 "(wrong ip6 dst)\n"));
157 goto bad;
158 }
159 } else if (!V_nd6_onlink_ns_rfc4861) {
160 struct sockaddr_in6 src_sa6;
161
162 /*
163 * According to recent IETF discussions, it is not a good idea
164 * to accept a NS from an address which would not be deemed
165 * to be a neighbor otherwise. This point is expected to be
166 * clarified in future revisions of the specification.
167 */
168 bzero(&src_sa6, sizeof(src_sa6));
169 src_sa6.sin6_family = AF_INET6;
170 src_sa6.sin6_len = sizeof(src_sa6);
171 src_sa6.sin6_addr = saddr6;
172 if (nd6_is_addr_neighbor(&src_sa6, ifp) == 0) {
173 nd6log((LOG_INFO, "nd6_ns_input: "
174 "NS packet from non-neighbor\n"));
175 goto bad;
176 }
177 }
178
179 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
180 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n"));
181 goto bad;
182 }
183
184 icmp6len -= sizeof(*nd_ns);
185 nd6_option_init(nd_ns + 1, icmp6len, &ndopts);
186 if (nd6_options(&ndopts) < 0) {
187 nd6log((LOG_INFO,
188 "nd6_ns_input: invalid ND option, ignored\n"));
189 /* nd6_options have incremented stats */
190 goto freeit;
191 }
192
193 if (ndopts.nd_opts_src_lladdr) {
194 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
195 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
196 }
197
198 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) {
199 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
200 "(link-layer address option)\n"));
201 goto bad;
202 }
203
204 /*
205 * Attaching target link-layer address to the NA?
206 * (RFC 2461 7.2.4)
207 *
208 * NS IP dst is unicast/anycast MUST NOT add
209 * NS IP dst is solicited-node multicast MUST add
210 *
211 * In implementation, we add target link-layer address by default.
212 * We do not add one in MUST NOT cases.
213 */
214 if (!IN6_IS_ADDR_MULTICAST(&daddr6))
215 tlladdr = 0;
216 else
217 tlladdr = 1;
218
219 /*
220 * Target address (taddr6) must be either:
221 * (1) Valid unicast/anycast address for my receiving interface,
222 * (2) Unicast address for which I'm offering proxy service, or
223 * (3) "tentative" address on which DAD is being performed.
224 */
225 /* (1) and (3) check. */
226 #ifdef DEV_CARP
227 if (ifp->if_carp)
228 ifa = carp_iamatch6(ifp->if_carp, &taddr6);
229 if (ifa == NULL)
230 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
231 #else
232 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
233 #endif
234
235 /* (2) check. */
236 if (ifa == NULL) {
237 struct rtentry *rt;
238 struct sockaddr_in6 tsin6;
239 int need_proxy;
240 #ifdef RADIX_MPATH
241 struct route_in6 ro;
242 #endif
243
244 bzero(&tsin6, sizeof tsin6);
245 tsin6.sin6_len = sizeof(struct sockaddr_in6);
246 tsin6.sin6_family = AF_INET6;
247 tsin6.sin6_addr = taddr6;
248
249 #ifdef RADIX_MPATH
250 bzero(&ro, sizeof(ro));
251 ro.ro_dst = tsin6;
252 rtalloc_mpath((struct route *)&ro, RTF_ANNOUNCE);
253 rt = ro.ro_rt;
254 #else
255 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0);
256 #endif
257 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 &&
258 rt->rt_gateway->sa_family == AF_LINK);
259 if (rt)
260 RTFREE_LOCKED(rt);
261 if (need_proxy) {
262 /*
263 * proxy NDP for single entry
264 */
265 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp,
266 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
267 if (ifa) {
268 proxy = 1;
269 proxydl = SDL(rt->rt_gateway);
270 }
271 }
272 }
273 if (ifa == NULL) {
274 /*
275 * We've got an NS packet, and we don't have that adddress
276 * assigned for us. We MUST silently ignore it.
277 * See RFC2461 7.2.3.
278 */
279 goto freeit;
280 }
281 myaddr6 = *IFA_IN6(ifa);
282 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST;
283 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE;
284 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED)
285 goto freeit;
286
287 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
288 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s "
289 "(if %d, NS packet %d)\n",
290 ip6_sprintf(ip6bufs, &taddr6),
291 ifp->if_addrlen, lladdrlen - 2));
292 goto bad;
293 }
294
295 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) {
296 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n",
297 ip6_sprintf(ip6bufs, &saddr6)));
298 goto freeit;
299 }
300
301 /*
302 * We have neighbor solicitation packet, with target address equals to
303 * one of my tentative address.
304 *
305 * src addr how to process?
306 * --- ---
307 * multicast of course, invalid (rejected in ip6_input)
308 * unicast somebody is doing address resolution -> ignore
309 * unspec dup address detection
310 *
311 * The processing is defined in RFC 2462.
312 */
313 if (tentative) {
314 /*
315 * If source address is unspecified address, it is for
316 * duplicate address detection.
317 *
318 * If not, the packet is for addess resolution;
319 * silently ignore it.
320 */
321 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6))
322 nd6_dad_ns_input(ifa);
323
324 goto freeit;
325 }
326
327 /*
328 * If the source address is unspecified address, entries must not
329 * be created or updated.
330 * It looks that sender is performing DAD. Output NA toward
331 * all-node multicast address, to tell the sender that I'm using
332 * the address.
333 * S bit ("solicited") must be zero.
334 */
335 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
336 struct in6_addr in6_all;
337
338 in6_all = in6addr_linklocal_allnodes;
339 if (in6_setscope(&in6_all, ifp, NULL) != 0)
340 goto bad;
341 nd6_na_output(ifp, &in6_all, &taddr6,
342 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
343 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0),
344 tlladdr, (struct sockaddr *)proxydl);
345 goto freeit;
346 }
347
348 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen,
349 ND_NEIGHBOR_SOLICIT, 0);
350
351 nd6_na_output(ifp, &saddr6, &taddr6,
352 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
353 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED,
354 tlladdr, (struct sockaddr *)proxydl);
355 freeit:
356 if (ifa != NULL)
357 ifa_free(ifa);
358 m_freem(m);
359 return;
360
361 bad:
362 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n",
363 ip6_sprintf(ip6bufs, &saddr6)));
364 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n",
365 ip6_sprintf(ip6bufs, &daddr6)));
366 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n",
367 ip6_sprintf(ip6bufs, &taddr6)));
368 ICMP6STAT_INC(icp6s_badns);
369 if (ifa != NULL)
370 ifa_free(ifa);
371 m_freem(m);
372 }
373
374 /*
375 * Output a Neighbor Solicitation Message. Caller specifies:
376 * - ICMP6 header source IP6 address
377 * - ND6 header target IP6 address
378 * - ND6 header source datalink address
379 *
380 * Based on RFC 2461
381 * Based on RFC 2462 (duplicate address detection)
382 *
383 * ln - for source address determination
384 * dad - duplicate address detection
385 */
386 void
387 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6,
388 const struct in6_addr *taddr6, struct llentry *ln, int dad)
389 {
390 struct mbuf *m;
391 struct ip6_hdr *ip6;
392 struct nd_neighbor_solicit *nd_ns;
393 struct in6_addr *src, src_in;
394 struct ip6_moptions im6o;
395 int icmp6len;
396 int maxlen;
397 caddr_t mac;
398 struct route_in6 ro;
399
400 bzero(&ro, sizeof(ro));
401
402 if (IN6_IS_ADDR_MULTICAST(taddr6))
403 return;
404
405 /* estimate the size of message */
406 maxlen = sizeof(*ip6) + sizeof(*nd_ns);
407 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
408 if (max_linkhdr + maxlen >= MCLBYTES) {
409 #ifdef DIAGNOSTIC
410 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES "
411 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
412 #endif
413 return;
414 }
415
416 MGETHDR(m, M_DONTWAIT, MT_DATA);
417 if (m && max_linkhdr + maxlen >= MHLEN) {
418 MCLGET(m, M_DONTWAIT);
419 if ((m->m_flags & M_EXT) == 0) {
420 m_free(m);
421 m = NULL;
422 }
423 }
424 if (m == NULL)
425 return;
426 m->m_pkthdr.rcvif = NULL;
427
428 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) {
429 m->m_flags |= M_MCAST;
430 im6o.im6o_multicast_ifp = ifp;
431 im6o.im6o_multicast_hlim = 255;
432 im6o.im6o_multicast_loop = 0;
433 }
434
435 icmp6len = sizeof(*nd_ns);
436 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len;
437 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
438
439 /* fill neighbor solicitation packet */
440 ip6 = mtod(m, struct ip6_hdr *);
441 ip6->ip6_flow = 0;
442 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
443 ip6->ip6_vfc |= IPV6_VERSION;
444 /* ip6->ip6_plen will be set later */
445 ip6->ip6_nxt = IPPROTO_ICMPV6;
446 ip6->ip6_hlim = 255;
447 if (daddr6)
448 ip6->ip6_dst = *daddr6;
449 else {
450 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
451 ip6->ip6_dst.s6_addr16[1] = 0;
452 ip6->ip6_dst.s6_addr32[1] = 0;
453 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE;
454 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3];
455 ip6->ip6_dst.s6_addr8[12] = 0xff;
456 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0)
457 goto bad;
458 }
459 if (!dad) {
460 struct ifaddr *ifa;
461
462 /*
463 * RFC2461 7.2.2:
464 * "If the source address of the packet prompting the
465 * solicitation is the same as one of the addresses assigned
466 * to the outgoing interface, that address SHOULD be placed
467 * in the IP Source Address of the outgoing solicitation.
468 * Otherwise, any one of the addresses assigned to the
469 * interface should be used."
470 *
471 * We use the source address for the prompting packet
472 * (saddr6), if:
473 * - saddr6 is given from the caller (by giving "ln"), and
474 * - saddr6 belongs to the outgoing interface.
475 * Otherwise, we perform the source address selection as usual.
476 */
477 struct ip6_hdr *hip6; /* hold ip6 */
478 struct in6_addr *hsrc = NULL;
479
480 if ((ln != NULL) && ln->la_hold) {
481 /*
482 * assuming every packet in la_hold has the same IP
483 * header
484 */
485 hip6 = mtod(ln->la_hold, struct ip6_hdr *);
486 /* XXX pullup? */
487 if (sizeof(*hip6) < ln->la_hold->m_len)
488 hsrc = &hip6->ip6_src;
489 else
490 hsrc = NULL;
491 }
492 if (hsrc && (ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp,
493 hsrc)) != NULL) {
494 src = hsrc;
495 ifa_free(ifa);
496 } else {
497 int error;
498 struct sockaddr_in6 dst_sa;
499
500 bzero(&dst_sa, sizeof(dst_sa));
501 dst_sa.sin6_family = AF_INET6;
502 dst_sa.sin6_len = sizeof(dst_sa);
503 dst_sa.sin6_addr = ip6->ip6_dst;
504
505 error = in6_selectsrc(&dst_sa, NULL,
506 NULL, &ro, NULL, NULL, &src_in);
507 if (error) {
508 char ip6buf[INET6_ADDRSTRLEN];
509 nd6log((LOG_DEBUG,
510 "nd6_ns_output: source can't be "
511 "determined: dst=%s, error=%d\n",
512 ip6_sprintf(ip6buf, &dst_sa.sin6_addr),
513 error));
514 goto bad;
515 }
516 src = &src_in;
517 }
518 } else {
519 /*
520 * Source address for DAD packet must always be IPv6
521 * unspecified address. (0::0)
522 * We actually don't have to 0-clear the address (we did it
523 * above), but we do so here explicitly to make the intention
524 * clearer.
525 */
526 bzero(&src_in, sizeof(src_in));
527 src = &src_in;
528 }
529 ip6->ip6_src = *src;
530 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1);
531 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT;
532 nd_ns->nd_ns_code = 0;
533 nd_ns->nd_ns_reserved = 0;
534 nd_ns->nd_ns_target = *taddr6;
535 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */
536
537 /*
538 * Add source link-layer address option.
539 *
540 * spec implementation
541 * --- ---
542 * DAD packet MUST NOT do not add the option
543 * there's no link layer address:
544 * impossible do not add the option
545 * there's link layer address:
546 * Multicast NS MUST add one add the option
547 * Unicast NS SHOULD add one add the option
548 */
549 if (!dad && (mac = nd6_ifptomac(ifp))) {
550 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
551 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
552 /* 8 byte alignments... */
553 optlen = (optlen + 7) & ~7;
554
555 m->m_pkthdr.len += optlen;
556 m->m_len += optlen;
557 icmp6len += optlen;
558 bzero((caddr_t)nd_opt, optlen);
559 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR;
560 nd_opt->nd_opt_len = optlen >> 3;
561 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
562 }
563
564 ip6->ip6_plen = htons((u_short)icmp6len);
565 nd_ns->nd_ns_cksum = 0;
566 nd_ns->nd_ns_cksum =
567 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len);
568
569 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL);
570 icmp6_ifstat_inc(ifp, ifs6_out_msg);
571 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit);
572 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_SOLICIT]);
573
574 if (ro.ro_rt) { /* we don't cache this route. */
575 RTFREE(ro.ro_rt);
576 }
577 return;
578
579 bad:
580 if (ro.ro_rt) {
581 RTFREE(ro.ro_rt);
582 }
583 m_freem(m);
584 return;
585 }
586
587 /*
588 * Neighbor advertisement input handling.
589 *
590 * Based on RFC 2461
591 * Based on RFC 2462 (duplicate address detection)
592 *
593 * the following items are not implemented yet:
594 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
595 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
596 */
597 void
598 nd6_na_input(struct mbuf *m, int off, int icmp6len)
599 {
600 struct ifnet *ifp = m->m_pkthdr.rcvif;
601 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
602 struct nd_neighbor_advert *nd_na;
603 struct in6_addr daddr6 = ip6->ip6_dst;
604 struct in6_addr taddr6;
605 int flags;
606 int is_router;
607 int is_solicited;
608 int is_override;
609 char *lladdr = NULL;
610 int lladdrlen = 0;
611 int checklink = 0;
612 struct ifaddr *ifa;
613 struct llentry *ln = NULL;
614 union nd_opts ndopts;
615 struct mbuf *chain = NULL;
616 struct sockaddr_in6 sin6;
617 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
618
619 if (ip6->ip6_hlim != 255) {
620 nd6log((LOG_ERR,
621 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n",
622 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
623 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
624 goto bad;
625 }
626
627 #ifndef PULLDOWN_TEST
628 IP6_EXTHDR_CHECK(m, off, icmp6len,);
629 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off);
630 #else
631 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len);
632 if (nd_na == NULL) {
633 ICMP6STAT_INC(icp6s_tooshort);
634 return;
635 }
636 #endif
637
638 flags = nd_na->nd_na_flags_reserved;
639 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0);
640 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0);
641 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0);
642
643 taddr6 = nd_na->nd_na_target;
644 if (in6_setscope(&taddr6, ifp, NULL))
645 goto bad; /* XXX: impossible */
646
647 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
648 nd6log((LOG_ERR,
649 "nd6_na_input: invalid target address %s\n",
650 ip6_sprintf(ip6bufs, &taddr6)));
651 goto bad;
652 }
653 if (IN6_IS_ADDR_MULTICAST(&daddr6))
654 if (is_solicited) {
655 nd6log((LOG_ERR,
656 "nd6_na_input: a solicited adv is multicasted\n"));
657 goto bad;
658 }
659
660 icmp6len -= sizeof(*nd_na);
661 nd6_option_init(nd_na + 1, icmp6len, &ndopts);
662 if (nd6_options(&ndopts) < 0) {
663 nd6log((LOG_INFO,
664 "nd6_na_input: invalid ND option, ignored\n"));
665 /* nd6_options have incremented stats */
666 goto freeit;
667 }
668
669 if (ndopts.nd_opts_tgt_lladdr) {
670 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
671 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
672 }
673
674 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
675
676 /*
677 * Target address matches one of my interface address.
678 *
679 * If my address is tentative, this means that there's somebody
680 * already using the same address as mine. This indicates DAD failure.
681 * This is defined in RFC 2462.
682 *
683 * Otherwise, process as defined in RFC 2461.
684 */
685 if (ifa
686 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) {
687 ifa_free(ifa);
688 nd6_dad_na_input(ifa);
689 goto freeit;
690 }
691
692 /* Just for safety, maybe unnecessary. */
693 if (ifa) {
694 ifa_free(ifa);
695 log(LOG_ERR,
696 "nd6_na_input: duplicate IP6 address %s\n",
697 ip6_sprintf(ip6bufs, &taddr6));
698 goto freeit;
699 }
700
701 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
702 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s "
703 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6),
704 ifp->if_addrlen, lladdrlen - 2));
705 goto bad;
706 }
707
708 /*
709 * If no neighbor cache entry is found, NA SHOULD silently be
710 * discarded.
711 */
712 IF_AFDATA_LOCK(ifp);
713 ln = nd6_lookup(&taddr6, LLE_EXCLUSIVE, ifp);
714 IF_AFDATA_UNLOCK(ifp);
715 if (ln == NULL) {
716 goto freeit;
717 }
718
719 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
720 /*
721 * If the link-layer has address, and no lladdr option came,
722 * discard the packet.
723 */
724 if (ifp->if_addrlen && lladdr == NULL) {
725 goto freeit;
726 }
727
728 /*
729 * Record link-layer address, and update the state.
730 */
731 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen);
732 ln->la_flags |= LLE_VALID;
733 if (is_solicited) {
734 ln->ln_state = ND6_LLINFO_REACHABLE;
735 ln->ln_byhint = 0;
736 if (!ND6_LLINFO_PERMANENT(ln)) {
737 nd6_llinfo_settimer_locked(ln,
738 (long)ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz);
739 }
740 } else {
741 ln->ln_state = ND6_LLINFO_STALE;
742 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz);
743 }
744 if ((ln->ln_router = is_router) != 0) {
745 /*
746 * This means a router's state has changed from
747 * non-reachable to probably reachable, and might
748 * affect the status of associated prefixes..
749 */
750 checklink = 1;
751 }
752 } else {
753 int llchange;
754
755 /*
756 * Check if the link-layer address has changed or not.
757 */
758 if (lladdr == NULL)
759 llchange = 0;
760 else {
761 if (ln->la_flags & LLE_VALID) {
762 if (bcmp(lladdr, &ln->ll_addr, ifp->if_addrlen))
763 llchange = 1;
764 else
765 llchange = 0;
766 } else
767 llchange = 1;
768 }
769
770 /*
771 * This is VERY complex. Look at it with care.
772 *
773 * override solicit lladdr llchange action
774 * (L: record lladdr)
775 *
776 * 0 0 n -- (2c)
777 * 0 0 y n (2b) L
778 * 0 0 y y (1) REACHABLE->STALE
779 * 0 1 n -- (2c) *->REACHABLE
780 * 0 1 y n (2b) L *->REACHABLE
781 * 0 1 y y (1) REACHABLE->STALE
782 * 1 0 n -- (2a)
783 * 1 0 y n (2a) L
784 * 1 0 y y (2a) L *->STALE
785 * 1 1 n -- (2a) *->REACHABLE
786 * 1 1 y n (2a) L *->REACHABLE
787 * 1 1 y y (2a) L *->REACHABLE
788 */
789 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */
790 /*
791 * If state is REACHABLE, make it STALE.
792 * no other updates should be done.
793 */
794 if (ln->ln_state == ND6_LLINFO_REACHABLE) {
795 ln->ln_state = ND6_LLINFO_STALE;
796 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz);
797 }
798 goto freeit;
799 } else if (is_override /* (2a) */
800 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */
801 || lladdr == NULL) { /* (2c) */
802 /*
803 * Update link-local address, if any.
804 */
805 if (lladdr != NULL) {
806 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen);
807 ln->la_flags |= LLE_VALID;
808 }
809
810 /*
811 * If solicited, make the state REACHABLE.
812 * If not solicited and the link-layer address was
813 * changed, make it STALE.
814 */
815 if (is_solicited) {
816 ln->ln_state = ND6_LLINFO_REACHABLE;
817 ln->ln_byhint = 0;
818 if (!ND6_LLINFO_PERMANENT(ln)) {
819 nd6_llinfo_settimer_locked(ln,
820 (long)ND_IFINFO(ifp)->reachable * hz);
821 }
822 } else {
823 if (lladdr != NULL && llchange) {
824 ln->ln_state = ND6_LLINFO_STALE;
825 nd6_llinfo_settimer_locked(ln,
826 (long)V_nd6_gctimer * hz);
827 }
828 }
829 }
830
831 if (ln->ln_router && !is_router) {
832 /*
833 * The peer dropped the router flag.
834 * Remove the sender from the Default Router List and
835 * update the Destination Cache entries.
836 */
837 struct nd_defrouter *dr;
838 struct in6_addr *in6;
839
840 in6 = &L3_ADDR_SIN6(ln)->sin6_addr;
841
842 /*
843 * Lock to protect the default router list.
844 * XXX: this might be unnecessary, since this function
845 * is only called under the network software interrupt
846 * context. However, we keep it just for safety.
847 */
848 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp);
849 if (dr)
850 defrtrlist_del(dr);
851 else if (!V_ip6_forwarding) {
852 /*
853 * Even if the neighbor is not in the default
854 * router list, the neighbor may be used
855 * as a next hop for some destinations
856 * (e.g. redirect case). So we must
857 * call rt6_flush explicitly.
858 */
859 rt6_flush(&ip6->ip6_src, ifp);
860 }
861 }
862 ln->ln_router = is_router;
863 }
864 /* XXX - QL
865 * Does this matter?
866 * rt->rt_flags &= ~RTF_REJECT;
867 */
868 ln->la_asked = 0;
869 if (ln->la_hold) {
870 struct mbuf *m_hold, *m_hold_next;
871
872 /*
873 * reset the la_hold in advance, to explicitly
874 * prevent a la_hold lookup in nd6_output()
875 * (wouldn't happen, though...)
876 */
877 for (m_hold = ln->la_hold, ln->la_hold = NULL;
878 m_hold; m_hold = m_hold_next) {
879 m_hold_next = m_hold->m_nextpkt;
880 m_hold->m_nextpkt = NULL;
881 /*
882 * we assume ifp is not a loopback here, so just set
883 * the 2nd argument as the 1st one.
884 */
885 nd6_output_lle(ifp, ifp, m_hold, L3_ADDR_SIN6(ln), NULL, ln, &chain);
886 }
887 }
888 freeit:
889 if (ln != NULL) {
890 if (chain)
891 memcpy(&sin6, L3_ADDR_SIN6(ln), sizeof(sin6));
892 LLE_WUNLOCK(ln);
893
894 if (chain)
895 nd6_output_flush(ifp, ifp, chain, &sin6, NULL);
896 }
897 if (checklink)
898 pfxlist_onlink_check();
899
900 m_freem(m);
901 return;
902
903 bad:
904 if (ln != NULL)
905 LLE_WUNLOCK(ln);
906
907 ICMP6STAT_INC(icp6s_badna);
908 m_freem(m);
909 }
910
911 /*
912 * Neighbor advertisement output handling.
913 *
914 * Based on RFC 2461
915 *
916 * the following items are not implemented yet:
917 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
918 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
919 *
920 * tlladdr - 1 if include target link-layer address
921 * sdl0 - sockaddr_dl (= proxy NA) or NULL
922 */
923 void
924 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0,
925 const struct in6_addr *taddr6, u_long flags, int tlladdr,
926 struct sockaddr *sdl0)
927 {
928 struct mbuf *m;
929 struct ip6_hdr *ip6;
930 struct nd_neighbor_advert *nd_na;
931 struct ip6_moptions im6o;
932 struct in6_addr src, daddr6;
933 struct sockaddr_in6 dst_sa;
934 int icmp6len, maxlen, error;
935 caddr_t mac = NULL;
936 struct route_in6 ro;
937
938 bzero(&ro, sizeof(ro));
939
940 daddr6 = *daddr6_0; /* make a local copy for modification */
941
942 /* estimate the size of message */
943 maxlen = sizeof(*ip6) + sizeof(*nd_na);
944 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
945 if (max_linkhdr + maxlen >= MCLBYTES) {
946 #ifdef DIAGNOSTIC
947 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES "
948 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
949 #endif
950 return;
951 }
952
953 MGETHDR(m, M_DONTWAIT, MT_DATA);
954 if (m && max_linkhdr + maxlen >= MHLEN) {
955 MCLGET(m, M_DONTWAIT);
956 if ((m->m_flags & M_EXT) == 0) {
957 m_free(m);
958 m = NULL;
959 }
960 }
961 if (m == NULL)
962 return;
963 m->m_pkthdr.rcvif = NULL;
964
965 if (IN6_IS_ADDR_MULTICAST(&daddr6)) {
966 m->m_flags |= M_MCAST;
967 im6o.im6o_multicast_ifp = ifp;
968 im6o.im6o_multicast_hlim = 255;
969 im6o.im6o_multicast_loop = 0;
970 }
971
972 icmp6len = sizeof(*nd_na);
973 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len;
974 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
975
976 /* fill neighbor advertisement packet */
977 ip6 = mtod(m, struct ip6_hdr *);
978 ip6->ip6_flow = 0;
979 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
980 ip6->ip6_vfc |= IPV6_VERSION;
981 ip6->ip6_nxt = IPPROTO_ICMPV6;
982 ip6->ip6_hlim = 255;
983 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) {
984 /* reply to DAD */
985 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
986 daddr6.s6_addr16[1] = 0;
987 daddr6.s6_addr32[1] = 0;
988 daddr6.s6_addr32[2] = 0;
989 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE;
990 if (in6_setscope(&daddr6, ifp, NULL))
991 goto bad;
992
993 flags &= ~ND_NA_FLAG_SOLICITED;
994 }
995 ip6->ip6_dst = daddr6;
996 bzero(&dst_sa, sizeof(struct sockaddr_in6));
997 dst_sa.sin6_family = AF_INET6;
998 dst_sa.sin6_len = sizeof(struct sockaddr_in6);
999 dst_sa.sin6_addr = daddr6;
1000
1001 /*
1002 * Select a source whose scope is the same as that of the dest.
1003 */
1004 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa));
1005 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &src);
1006 if (error) {
1007 char ip6buf[INET6_ADDRSTRLEN];
1008 nd6log((LOG_DEBUG, "nd6_na_output: source can't be "
1009 "determined: dst=%s, error=%d\n",
1010 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error));
1011 goto bad;
1012 }
1013 ip6->ip6_src = src;
1014 nd_na = (struct nd_neighbor_advert *)(ip6 + 1);
1015 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT;
1016 nd_na->nd_na_code = 0;
1017 nd_na->nd_na_target = *taddr6;
1018 in6_clearscope(&nd_na->nd_na_target); /* XXX */
1019
1020 /*
1021 * "tlladdr" indicates NS's condition for adding tlladdr or not.
1022 * see nd6_ns_input() for details.
1023 * Basically, if NS packet is sent to unicast/anycast addr,
1024 * target lladdr option SHOULD NOT be included.
1025 */
1026 if (tlladdr) {
1027 /*
1028 * sdl0 != NULL indicates proxy NA. If we do proxy, use
1029 * lladdr in sdl0. If we are not proxying (sending NA for
1030 * my address) use lladdr configured for the interface.
1031 */
1032 if (sdl0 == NULL) {
1033 #ifdef DEV_CARP
1034 if (ifp->if_carp)
1035 mac = carp_macmatch6(ifp->if_carp, m, taddr6);
1036 if (mac == NULL)
1037 mac = nd6_ifptomac(ifp);
1038 #else
1039 mac = nd6_ifptomac(ifp);
1040 #endif
1041 } else if (sdl0->sa_family == AF_LINK) {
1042 struct sockaddr_dl *sdl;
1043 sdl = (struct sockaddr_dl *)sdl0;
1044 if (sdl->sdl_alen == ifp->if_addrlen)
1045 mac = LLADDR(sdl);
1046 }
1047 }
1048 if (tlladdr && mac) {
1049 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
1050 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1);
1051
1052 /* roundup to 8 bytes alignment! */
1053 optlen = (optlen + 7) & ~7;
1054
1055 m->m_pkthdr.len += optlen;
1056 m->m_len += optlen;
1057 icmp6len += optlen;
1058 bzero((caddr_t)nd_opt, optlen);
1059 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
1060 nd_opt->nd_opt_len = optlen >> 3;
1061 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
1062 } else
1063 flags &= ~ND_NA_FLAG_OVERRIDE;
1064
1065 ip6->ip6_plen = htons((u_short)icmp6len);
1066 nd_na->nd_na_flags_reserved = flags;
1067 nd_na->nd_na_cksum = 0;
1068 nd_na->nd_na_cksum =
1069 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len);
1070
1071 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL);
1072 icmp6_ifstat_inc(ifp, ifs6_out_msg);
1073 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert);
1074 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]);
1075
1076 if (ro.ro_rt) { /* we don't cache this route. */
1077 RTFREE(ro.ro_rt);
1078 }
1079 return;
1080
1081 bad:
1082 if (ro.ro_rt) {
1083 RTFREE(ro.ro_rt);
1084 }
1085 m_freem(m);
1086 return;
1087 }
1088
1089 caddr_t
1090 nd6_ifptomac(struct ifnet *ifp)
1091 {
1092 switch (ifp->if_type) {
1093 case IFT_ARCNET:
1094 case IFT_ETHER:
1095 case IFT_FDDI:
1096 case IFT_IEEE1394:
1097 #ifdef IFT_L2VLAN
1098 case IFT_L2VLAN:
1099 #endif
1100 #ifdef IFT_IEEE80211
1101 case IFT_IEEE80211:
1102 #endif
1103 #ifdef IFT_CARP
1104 case IFT_CARP:
1105 #endif
1106 case IFT_BRIDGE:
1107 case IFT_ISO88025:
1108 return IF_LLADDR(ifp);
1109 default:
1110 return NULL;
1111 }
1112 }
1113
1114 struct dadq {
1115 TAILQ_ENTRY(dadq) dad_list;
1116 struct ifaddr *dad_ifa;
1117 int dad_count; /* max NS to send */
1118 int dad_ns_tcount; /* # of trials to send NS */
1119 int dad_ns_ocount; /* NS sent so far */
1120 int dad_ns_icount;
1121 int dad_na_icount;
1122 struct callout dad_timer_ch;
1123 struct vnet *dad_vnet;
1124 };
1125
1126 static VNET_DEFINE(TAILQ_HEAD(, dadq), dadq);
1127 #define V_dadq VNET(dadq)
1128
1129 VNET_DEFINE(int, dad_init);
1130 #define V_dad_init VNET(dad_init)
1131
1132 static struct dadq *
1133 nd6_dad_find(struct ifaddr *ifa)
1134 {
1135 struct dadq *dp;
1136
1137 for (dp = V_dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) {
1138 if (dp->dad_ifa == ifa)
1139 return dp;
1140 }
1141 return NULL;
1142 }
1143
1144 static void
1145 nd6_dad_starttimer(struct dadq *dp, int ticks)
1146 {
1147
1148 callout_reset(&dp->dad_timer_ch, ticks,
1149 (void (*)(void *))nd6_dad_timer, (void *)dp);
1150 }
1151
1152 static void
1153 nd6_dad_stoptimer(struct dadq *dp)
1154 {
1155
1156 callout_stop(&dp->dad_timer_ch);
1157 }
1158
1159 /*
1160 * Start Duplicate Address Detection (DAD) for specified interface address.
1161 */
1162 void
1163 nd6_dad_start(struct ifaddr *ifa, int delay)
1164 {
1165 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1166 struct dadq *dp;
1167 char ip6buf[INET6_ADDRSTRLEN];
1168
1169 if (!V_dad_init) {
1170 TAILQ_INIT(&V_dadq);
1171 V_dad_init++;
1172 }
1173
1174 /*
1175 * If we don't need DAD, don't do it.
1176 * There are several cases:
1177 * - DAD is disabled (ip6_dad_count == 0)
1178 * - the interface address is anycast
1179 */
1180 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
1181 log(LOG_DEBUG,
1182 "nd6_dad_start: called with non-tentative address "
1183 "%s(%s)\n",
1184 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1185 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1186 return;
1187 }
1188 if (ia->ia6_flags & IN6_IFF_ANYCAST) {
1189 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1190 return;
1191 }
1192 if (!V_ip6_dad_count) {
1193 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1194 return;
1195 }
1196 if (ifa->ifa_ifp == NULL)
1197 panic("nd6_dad_start: ifa->ifa_ifp == NULL");
1198 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) {
1199 return;
1200 }
1201 if (nd6_dad_find(ifa) != NULL) {
1202 /* DAD already in progress */
1203 return;
1204 }
1205
1206 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT);
1207 if (dp == NULL) {
1208 log(LOG_ERR, "nd6_dad_start: memory allocation failed for "
1209 "%s(%s)\n",
1210 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1211 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1212 return;
1213 }
1214 bzero(dp, sizeof(*dp));
1215 callout_init(&dp->dad_timer_ch, 0);
1216 #ifdef VIMAGE
1217 dp->dad_vnet = curvnet;
1218 #endif
1219 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list);
1220
1221 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp),
1222 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1223
1224 /*
1225 * Send NS packet for DAD, ip6_dad_count times.
1226 * Note that we must delay the first transmission, if this is the
1227 * first packet to be sent from the interface after interface
1228 * (re)initialization.
1229 */
1230 dp->dad_ifa = ifa;
1231 ifa_ref(ifa); /* just for safety */
1232 dp->dad_count = V_ip6_dad_count;
1233 dp->dad_ns_icount = dp->dad_na_icount = 0;
1234 dp->dad_ns_ocount = dp->dad_ns_tcount = 0;
1235 if (delay == 0) {
1236 nd6_dad_ns_output(dp, ifa);
1237 nd6_dad_starttimer(dp,
1238 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1239 } else {
1240 nd6_dad_starttimer(dp, delay);
1241 }
1242 }
1243
1244 /*
1245 * terminate DAD unconditionally. used for address removals.
1246 */
1247 void
1248 nd6_dad_stop(struct ifaddr *ifa)
1249 {
1250 struct dadq *dp;
1251
1252 if (!V_dad_init)
1253 return;
1254 dp = nd6_dad_find(ifa);
1255 if (!dp) {
1256 /* DAD wasn't started yet */
1257 return;
1258 }
1259
1260 nd6_dad_stoptimer(dp);
1261
1262 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list);
1263 free(dp, M_IP6NDP);
1264 dp = NULL;
1265 ifa_free(ifa);
1266 }
1267
1268 static void
1269 nd6_dad_timer(struct dadq *dp)
1270 {
1271 CURVNET_SET(dp->dad_vnet);
1272 int s;
1273 struct ifaddr *ifa = dp->dad_ifa;
1274 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1275 char ip6buf[INET6_ADDRSTRLEN];
1276
1277 s = splnet(); /* XXX */
1278
1279 /* Sanity check */
1280 if (ia == NULL) {
1281 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n");
1282 goto done;
1283 }
1284 if (ia->ia6_flags & IN6_IFF_DUPLICATED) {
1285 log(LOG_ERR, "nd6_dad_timer: called with duplicated address "
1286 "%s(%s)\n",
1287 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1288 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1289 goto done;
1290 }
1291 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) {
1292 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address "
1293 "%s(%s)\n",
1294 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1295 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1296 goto done;
1297 }
1298
1299 /* timeouted with IFF_{RUNNING,UP} check */
1300 if (dp->dad_ns_tcount > V_dad_maxtry) {
1301 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n",
1302 if_name(ifa->ifa_ifp)));
1303
1304 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list);
1305 free(dp, M_IP6NDP);
1306 dp = NULL;
1307 ifa_free(ifa);
1308 goto done;
1309 }
1310
1311 /* Need more checks? */
1312 if (dp->dad_ns_ocount < dp->dad_count) {
1313 /*
1314 * We have more NS to go. Send NS packet for DAD.
1315 */
1316 nd6_dad_ns_output(dp, ifa);
1317 nd6_dad_starttimer(dp,
1318 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1319 } else {
1320 /*
1321 * We have transmitted sufficient number of DAD packets.
1322 * See what we've got.
1323 */
1324 int duplicate;
1325
1326 duplicate = 0;
1327
1328 if (dp->dad_na_icount) {
1329 /*
1330 * the check is in nd6_dad_na_input(),
1331 * but just in case
1332 */
1333 duplicate++;
1334 }
1335
1336 if (dp->dad_ns_icount) {
1337 /* We've seen NS, means DAD has failed. */
1338 duplicate++;
1339 }
1340
1341 if (duplicate) {
1342 /* (*dp) will be freed in nd6_dad_duplicated() */
1343 dp = NULL;
1344 nd6_dad_duplicated(ifa);
1345 } else {
1346 /*
1347 * We are done with DAD. No NA came, no NS came.
1348 * No duplicate address found.
1349 */
1350 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1351
1352 nd6log((LOG_DEBUG,
1353 "%s: DAD complete for %s - no duplicates found\n",
1354 if_name(ifa->ifa_ifp),
1355 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1356
1357 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list);
1358 free(dp, M_IP6NDP);
1359 dp = NULL;
1360 ifa_free(ifa);
1361 }
1362 }
1363
1364 done:
1365 splx(s);
1366 CURVNET_RESTORE();
1367 }
1368
1369 void
1370 nd6_dad_duplicated(struct ifaddr *ifa)
1371 {
1372 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1373 struct ifnet *ifp;
1374 struct dadq *dp;
1375 char ip6buf[INET6_ADDRSTRLEN];
1376
1377 dp = nd6_dad_find(ifa);
1378 if (dp == NULL) {
1379 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n");
1380 return;
1381 }
1382
1383 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: "
1384 "NS in/out=%d/%d, NA in=%d\n",
1385 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1386 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount);
1387
1388 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1389 ia->ia6_flags |= IN6_IFF_DUPLICATED;
1390
1391 /* We are done with DAD, with duplicate address found. (failure) */
1392 nd6_dad_stoptimer(dp);
1393
1394 ifp = ifa->ifa_ifp;
1395 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n",
1396 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr));
1397 log(LOG_ERR, "%s: manual intervention required\n",
1398 if_name(ifp));
1399
1400 /*
1401 * If the address is a link-local address formed from an interface
1402 * identifier based on the hardware address which is supposed to be
1403 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP
1404 * operation on the interface SHOULD be disabled.
1405 * [rfc2462bis-03 Section 5.4.5]
1406 */
1407 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) {
1408 struct in6_addr in6;
1409
1410 /*
1411 * To avoid over-reaction, we only apply this logic when we are
1412 * very sure that hardware addresses are supposed to be unique.
1413 */
1414 switch (ifp->if_type) {
1415 case IFT_ETHER:
1416 case IFT_FDDI:
1417 case IFT_ATM:
1418 case IFT_IEEE1394:
1419 #ifdef IFT_IEEE80211
1420 case IFT_IEEE80211:
1421 #endif
1422 in6 = ia->ia_addr.sin6_addr;
1423 if (in6_get_hw_ifid(ifp, &in6) == 0 &&
1424 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) {
1425 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED;
1426 log(LOG_ERR, "%s: possible hardware address "
1427 "duplication detected, disable IPv6\n",
1428 if_name(ifp));
1429 }
1430 break;
1431 }
1432 }
1433
1434 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list);
1435 free(dp, M_IP6NDP);
1436 dp = NULL;
1437 ifa_free(ifa);
1438 }
1439
1440 static void
1441 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa)
1442 {
1443 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1444 struct ifnet *ifp = ifa->ifa_ifp;
1445
1446 dp->dad_ns_tcount++;
1447 if ((ifp->if_flags & IFF_UP) == 0) {
1448 return;
1449 }
1450 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
1451 return;
1452 }
1453
1454 dp->dad_ns_ocount++;
1455 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1);
1456 }
1457
1458 static void
1459 nd6_dad_ns_input(struct ifaddr *ifa)
1460 {
1461 struct in6_ifaddr *ia;
1462 struct ifnet *ifp;
1463 const struct in6_addr *taddr6;
1464 struct dadq *dp;
1465 int duplicate;
1466
1467 if (ifa == NULL)
1468 panic("ifa == NULL in nd6_dad_ns_input");
1469
1470 ia = (struct in6_ifaddr *)ifa;
1471 ifp = ifa->ifa_ifp;
1472 taddr6 = &ia->ia_addr.sin6_addr;
1473 duplicate = 0;
1474 dp = nd6_dad_find(ifa);
1475
1476 /* Quickhack - completely ignore DAD NS packets */
1477 if (V_dad_ignore_ns) {
1478 char ip6buf[INET6_ADDRSTRLEN];
1479 nd6log((LOG_INFO,
1480 "nd6_dad_ns_input: ignoring DAD NS packet for "
1481 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6),
1482 if_name(ifa->ifa_ifp)));
1483 return;
1484 }
1485
1486 /*
1487 * if I'm yet to start DAD, someone else started using this address
1488 * first. I have a duplicate and you win.
1489 */
1490 if (dp == NULL || dp->dad_ns_ocount == 0)
1491 duplicate++;
1492
1493 /* XXX more checks for loopback situation - see nd6_dad_timer too */
1494
1495 if (duplicate) {
1496 dp = NULL; /* will be freed in nd6_dad_duplicated() */
1497 nd6_dad_duplicated(ifa);
1498 } else {
1499 /*
1500 * not sure if I got a duplicate.
1501 * increment ns count and see what happens.
1502 */
1503 if (dp)
1504 dp->dad_ns_icount++;
1505 }
1506 }
1507
1508 static void
1509 nd6_dad_na_input(struct ifaddr *ifa)
1510 {
1511 struct dadq *dp;
1512
1513 if (ifa == NULL)
1514 panic("ifa == NULL in nd6_dad_na_input");
1515
1516 dp = nd6_dad_find(ifa);
1517 if (dp)
1518 dp->dad_na_icount++;
1519
1520 /* remove the address. */
1521 nd6_dad_duplicated(ifa);
1522 }
Cache object: c90ad24a25464d9bc27e8e69a2a6ce8c
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