1/* $NetBSD: nd6_nbr.c,v 1.130 2016/11/15 21:17:07 mlelstv Exp $ */
2/* $KAME: nd6_nbr.c,v 1.61 2001/02/10 16:06:14 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 <sys/cdefs.h>
34__KERNEL_RCSID(0, "$NetBSD: nd6_nbr.c,v 1.130 2016/11/15 21:17:07 mlelstv Exp $");
35
36#ifdef _KERNEL_OPT
37#include "opt_inet.h"
38#include "opt_net_mpsafe.h"
39#endif
40
41#include <sys/param.h>
42#include <sys/systm.h>
43#include <sys/malloc.h>
44#include <sys/mbuf.h>
45#include <sys/socket.h>
46#include <sys/socketvar.h>
47#include <sys/sockio.h>
48#include <sys/time.h>
49#include <sys/kernel.h>
50#include <sys/errno.h>
51#include <sys/ioctl.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/route.h>
60
61#include <netinet/in.h>
62#include <netinet/in_var.h>
63#include <netinet6/in6_var.h>
64#include <netinet6/in6_ifattach.h>
65#include <netinet/ip6.h>
66#include <netinet6/ip6_var.h>
67#include <netinet6/scope6_var.h>
68#include <netinet6/nd6.h>
69#include <netinet/icmp6.h>
70#include <netinet6/icmp6_private.h>
71
72#include "carp.h"
73#if NCARP > 0
74#include <netinet/ip_carp.h>
75#endif
76
77#include <net/net_osdep.h>
78
79struct dadq;
80static struct dadq *nd6_dad_find(struct ifaddr *);
81static void nd6_dad_starttimer(struct dadq *, int);
82static void nd6_dad_stoptimer(struct dadq *);
83static void nd6_dad_timer(struct ifaddr *);
84static void nd6_dad_ns_output(struct dadq *, struct ifaddr *);
85static void nd6_dad_ns_input(struct ifaddr *);
86static void nd6_dad_na_input(struct ifaddr *);
87
88static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/
89static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */
90
91/*
92 * Input a Neighbor Solicitation Message.
93 *
94 * Based on RFC 2461
95 * Based on RFC 2462 (duplicate address detection)
96 */
97void
98nd6_ns_input(struct mbuf *m, int off, int icmp6len)
99{
100 struct ifnet *ifp;
101 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
102 struct nd_neighbor_solicit *nd_ns;
103 struct in6_addr saddr6 = ip6->ip6_src;
104 struct in6_addr daddr6 = ip6->ip6_dst;
105 struct in6_addr taddr6;
106 struct in6_addr myaddr6;
107 char *lladdr = NULL;
108 struct ifaddr *ifa = NULL;
109 int lladdrlen = 0;
110 int anycast = 0, proxy = 0, tentative = 0;
111 int router = ip6_forwarding;
112 int tlladdr;
113 union nd_opts ndopts;
114 const struct sockaddr_dl *proxydl = NULL;
115 struct psref psref;
116 struct psref psref_ia;
117
118 ifp = m_get_rcvif_psref(m, &psref);
119 if (ifp == NULL)
120 goto freeit;
121
122 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len);
123 if (nd_ns == NULL) {
124 ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
125 m_put_rcvif_psref(ifp, &psref);
126 return;
127 }
128 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */
129 taddr6 = nd_ns->nd_ns_target;
130 if (in6_setscope(&taddr6, ifp, NULL) != 0)
131 goto bad;
132
133 if (ip6->ip6_hlim != 255) {
134 nd6log(LOG_ERR, "invalid hlim (%d) from %s to %s on %s\n",
135 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src),
136 ip6_sprintf(&ip6->ip6_dst), if_name(ifp));
137 goto bad;
138 }
139
140 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
141 /* dst has to be a solicited node multicast address. */
142 /* don't check ifindex portion */
143 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL &&
144 daddr6.s6_addr32[1] == 0 &&
145 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE &&
146 daddr6.s6_addr8[12] == 0xff) {
147 ; /* good */
148 } else {
149 nd6log(LOG_INFO, "bad DAD packet (wrong ip6 dst)\n");
150 goto bad;
151 }
152 } else {
153 struct sockaddr_in6 ssin6;
154
155 /*
156 * Make sure the source address is from a neighbor's address.
157 */
158 sockaddr_in6_init(&ssin6, &saddr6, 0, 0, 0);
159 if (nd6_is_addr_neighbor(&ssin6, ifp) == 0) {
160 nd6log(LOG_INFO,
161 "NS packet from non-neighbor %s on %s\n",
162 ip6_sprintf(&saddr6), if_name(ifp));
163 goto bad;
164 }
165 }
166
167
168 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
169 nd6log(LOG_INFO, "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, "invalid ND option, ignored\n");
177 /* nd6_options have incremented stats */
178 goto freeit;
179 }
180
181 if (ndopts.nd_opts_src_lladdr) {
182 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
183 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
184 }
185
186 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) {
187 nd6log(LOG_INFO,
188 "bad DAD packet (link-layer address option)\n");
189 goto bad;
190 }
191
192 /*
193 * Attaching target link-layer address to the NA?
194 * (RFC 2461 7.2.4)
195 *
196 * NS IP dst is multicast MUST add
197 * Otherwise MAY be omitted
198 *
199 * In this implementation, we omit the target link-layer address
200 * in the "MAY" case.
201 */
202#if 0 /* too much! */
203 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6);
204 if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST))
205 tlladdr = 0;
206 else
207#endif
208 if (!IN6_IS_ADDR_MULTICAST(&daddr6))
209 tlladdr = 0;
210 else
211 tlladdr = 1;
212
213 /*
214 * Target address (taddr6) must be either:
215 * (1) Valid unicast/anycast address for my receiving interface,
216 * (2) Unicast address for which I'm offering proxy service, or
217 * (3) "tentative" address on which DAD is being performed.
218 */
219 /* (1) and (3) check. */
220#if NCARP > 0
221 if (ifp->if_carp && ifp->if_type != IFT_CARP) {
222 int s = pserialize_read_enter();
223 ifa = carp_iamatch6(ifp->if_carp, &taddr6);
224 if (ifa != NULL)
225 ifa_acquire(ifa, &psref_ia);
226 pserialize_read_exit(s);
227 } else
228 ifa = NULL;
229 if (!ifa)
230 ifa = (struct ifaddr *)in6ifa_ifpwithaddr_psref(ifp, &taddr6,
231 &psref_ia);
232#else
233 ifa = (struct ifaddr *)in6ifa_ifpwithaddr_psref(ifp, &taddr6,
234 &psref_ia);
235#endif
236
237 /* (2) check. */
238 if (ifa == NULL) {
239 struct rtentry *rt;
240 struct sockaddr_in6 tsin6;
241
242 sockaddr_in6_init(&tsin6, &taddr6, 0, 0, 0);
243
244 rt = rtalloc1(sin6tosa(&tsin6), 0);
245 if (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 &&
246 rt->rt_gateway->sa_family == AF_LINK) {
247 /*
248 * proxy NDP for single entry
249 */
250 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal_psref(ifp,
251 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST, &psref_ia);
252 if (ifa) {
253 proxy = 1;
254 proxydl = satocsdl(rt->rt_gateway);
255 router = 0; /* XXX */
256 }
257 }
258 if (rt)
259 rtfree(rt);
260 }
261 if (ifa == NULL) {
262 /*
263 * We've got an NS packet, and we don't have that address
264 * assigned for us. We MUST silently ignore it.
265 * See RFC2461 7.2.3.
266 */
267 goto freeit;
268 }
269 myaddr6 = *IFA_IN6(ifa);
270 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST;
271 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE;
272 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED)
273 goto freeit;
274
275 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
276 nd6log(LOG_INFO, "lladdrlen mismatch for %s "
277 "(if %d, NS packet %d)\n",
278 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2);
279 goto bad;
280 }
281
282 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) {
283 nd6log(LOG_INFO, "duplicate IP6 address %s\n",
284 ip6_sprintf(&saddr6));
285 goto freeit;
286 }
287
288 /*
289 * We have neighbor solicitation packet, with target address equals to
290 * one of my tentative address.
291 *
292 * src addr how to process?
293 * --- ---
294 * multicast of course, invalid (rejected in ip6_input)
295 * unicast somebody is doing address resolution -> ignore
296 * unspec dup address detection
297 *
298 * The processing is defined in RFC 2462.
299 */
300 if (tentative) {
301 /*
302 * If source address is unspecified address, it is for
303 * duplicate address detection.
304 *
305 * If not, the packet is for addess resolution;
306 * silently ignore it.
307 */
308 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6))
309 nd6_dad_ns_input(ifa);
310 ifa_release(ifa, &psref_ia);
311 ifa = NULL;
312
313 goto freeit;
314 }
315 ifa_release(ifa, &psref_ia);
316 ifa = NULL;
317
318 /*
319 * If the source address is unspecified address, entries must not
320 * be created or updated.
321 * It looks that sender is performing DAD. Output NA toward
322 * all-node multicast address, to tell the sender that I'm using
323 * the address.
324 * S bit ("solicited") must be zero.
325 */
326 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
327 struct in6_addr in6_all;
328
329 in6_all = in6addr_linklocal_allnodes;
330 if (in6_setscope(&in6_all, ifp, NULL) != 0)
331 goto bad;
332 nd6_na_output(ifp, &in6_all, &taddr6,
333 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
334 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0),
335 tlladdr, (const struct sockaddr *)proxydl);
336 goto freeit;
337 }
338
339 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_NEIGHBOR_SOLICIT, 0);
340
341 nd6_na_output(ifp, &saddr6, &taddr6,
342 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
343 (router ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED,
344 tlladdr, (const struct sockaddr *)proxydl);
345 freeit:
346 ifa_release(ifa, &psref_ia);
347 m_put_rcvif_psref(ifp, &psref);
348 m_freem(m);
349 return;
350
351 bad:
352 nd6log(LOG_ERR, "src=%s\n", ip6_sprintf(&saddr6));
353 nd6log(LOG_ERR, "dst=%s\n", ip6_sprintf(&daddr6));
354 nd6log(LOG_ERR, "tgt=%s\n", ip6_sprintf(&taddr6));
355 ICMP6_STATINC(ICMP6_STAT_BADNS);
356 ifa_release(ifa, &psref_ia);
357 m_put_rcvif_psref(ifp, &psref);
358 m_freem(m);
359}
360
361/*
362 * Output a Neighbor Solicitation Message. Caller specifies:
363 * - ICMP6 header source IP6 address
364 * - ND6 header target IP6 address
365 * - ND6 header source datalink address
366 *
367 * Based on RFC 2461
368 * Based on RFC 2462 (duplicate address detection)
369 */
370void
371nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6,
372 const struct in6_addr *taddr6,
373 struct in6_addr *hsrc,
374 int dad /* duplicate address detection */)
375{
376 struct mbuf *m;
377 struct ip6_hdr *ip6;
378 struct nd_neighbor_solicit *nd_ns;
379 struct in6_addr *src, src_in;
380 struct ip6_moptions im6o;
381 int icmp6len;
382 int maxlen;
383 const void *mac;
384 struct route ro;
385
386 if (IN6_IS_ADDR_MULTICAST(taddr6))
387 return;
388
389 memset(&ro, 0, sizeof(ro));
390
391 /* estimate the size of message */
392 maxlen = sizeof(*ip6) + sizeof(*nd_ns);
393 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
394#ifdef DIAGNOSTIC
395 if (max_linkhdr + maxlen >= MCLBYTES) {
396 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES "
397 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
398 panic("nd6_ns_output: insufficient MCLBYTES");
399 /* NOTREACHED */
400 }
401#endif
402
403 MGETHDR(m, M_DONTWAIT, MT_DATA);
404 if (m && max_linkhdr + maxlen >= MHLEN) {
405 MCLGET(m, M_DONTWAIT);
406 if ((m->m_flags & M_EXT) == 0) {
407 m_free(m);
408 m = NULL;
409 }
410 }
411 if (m == NULL)
412 return;
413 m_reset_rcvif(m);
414
415 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) {
416 m->m_flags |= M_MCAST;
417 im6o.im6o_multicast_if_index = if_get_index(ifp);
418 im6o.im6o_multicast_hlim = 255;
419 im6o.im6o_multicast_loop = 0;
420 }
421
422 icmp6len = sizeof(*nd_ns);
423 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len;
424 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
425
426 /* fill neighbor solicitation packet */
427 ip6 = mtod(m, struct ip6_hdr *);
428 ip6->ip6_flow = 0;
429 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
430 ip6->ip6_vfc |= IPV6_VERSION;
431 /* ip6->ip6_plen will be set later */
432 ip6->ip6_nxt = IPPROTO_ICMPV6;
433 ip6->ip6_hlim = 255;
434 if (daddr6)
435 ip6->ip6_dst = *daddr6;
436 else {
437 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
438 ip6->ip6_dst.s6_addr16[1] = 0;
439 ip6->ip6_dst.s6_addr32[1] = 0;
440 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE;
441 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3];
442 ip6->ip6_dst.s6_addr8[12] = 0xff;
443 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0)
444 goto bad;
445 }
446 if (!dad) {
447 int s;
448 /*
449 * RFC2461 7.2.2:
450 * "If the source address of the packet prompting the
451 * solicitation is the same as one of the addresses assigned
452 * to the outgoing interface, that address SHOULD be placed
453 * in the IP Source Address of the outgoing solicitation.
454 * Otherwise, any one of the addresses assigned to the
455 * interface should be used."
456 *
457 * We use the source address for the prompting packet
458 * (hsrc), if:
459 * - hsrc is given from the caller (by giving "ln"), and
460 * - hsrc belongs to the outgoing interface.
461 * Otherwise, we perform the source address selection as usual.
462 */
463 s = pserialize_read_enter();
464 if (hsrc && in6ifa_ifpwithaddr(ifp, hsrc))
465 src = hsrc;
466 else {
467 int error;
468 struct sockaddr_in6 dst_sa;
469
470 sockaddr_in6_init(&dst_sa, &ip6->ip6_dst, 0, 0, 0);
471
472 error = in6_selectsrc(&dst_sa, NULL,
473 NULL, &ro, NULL, NULL, NULL, &src_in);
474 if (error != 0) {
475 nd6log(LOG_DEBUG, "source can't be "
476 "determined: dst=%s, error=%d\n",
477 ip6_sprintf(&dst_sa.sin6_addr), error);
478 pserialize_read_exit(s);
479 goto bad;
480 }
481 src = &src_in;
482 }
483 pserialize_read_exit(s);
484 } else {
485 /*
486 * Source address for DAD packet must always be IPv6
487 * unspecified address. (0::0)
488 * We actually don't have to 0-clear the address (we did it
489 * above), but we do so here explicitly to make the intention
490 * clearer.
491 */
492 memset(&src_in, 0, sizeof(src_in));
493 src = &src_in;
494 }
495 ip6->ip6_src = *src;
496 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1);
497 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT;
498 nd_ns->nd_ns_code = 0;
499 nd_ns->nd_ns_reserved = 0;
500 nd_ns->nd_ns_target = *taddr6;
501 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */
502
503 /*
504 * Add source link-layer address option.
505 *
506 * spec implementation
507 * --- ---
508 * DAD packet MUST NOT do not add the option
509 * there's no link layer address:
510 * impossible do not add the option
511 * there's link layer address:
512 * Multicast NS MUST add one add the option
513 * Unicast NS SHOULD add one add the option
514 */
515 if (!dad && (mac = nd6_ifptomac(ifp))) {
516 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
517 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
518 /* 8 byte alignments... */
519 optlen = (optlen + 7) & ~7;
520
521 m->m_pkthdr.len += optlen;
522 m->m_len += optlen;
523 icmp6len += optlen;
524 memset((void *)nd_opt, 0, optlen);
525 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR;
526 nd_opt->nd_opt_len = optlen >> 3;
527 memcpy((void *)(nd_opt + 1), mac, ifp->if_addrlen);
528 }
529
530 ip6->ip6_plen = htons((u_int16_t)icmp6len);
531 nd_ns->nd_ns_cksum = 0;
532 nd_ns->nd_ns_cksum =
533 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len);
534
535 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL);
536 icmp6_ifstat_inc(ifp, ifs6_out_msg);
537 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit);
538 ICMP6_STATINC(ICMP6_STAT_OUTHIST + ND_NEIGHBOR_SOLICIT);
539
540 rtcache_free(&ro);
541 return;
542
543 bad:
544 rtcache_free(&ro);
545 m_freem(m);
546 return;
547}
548
549/*
550 * Neighbor advertisement input handling.
551 *
552 * Based on RFC 2461
553 * Based on RFC 2462 (duplicate address detection)
554 *
555 * the following items are not implemented yet:
556 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
557 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
558 */
559void
560nd6_na_input(struct mbuf *m, int off, int icmp6len)
561{
562 struct ifnet *ifp;
563 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
564 struct nd_neighbor_advert *nd_na;
565 struct in6_addr saddr6 = ip6->ip6_src;
566 struct in6_addr daddr6 = ip6->ip6_dst;
567 struct in6_addr taddr6;
568 int flags;
569 int is_router;
570 int is_solicited;
571 int is_override;
572 char *lladdr = NULL;
573 int lladdrlen = 0;
574 struct ifaddr *ifa;
575 struct llentry *ln = NULL;
576 union nd_opts ndopts;
577 struct sockaddr_in6 ssin6;
578 int rt_announce;
579 bool checklink = false;
580 struct psref psref;
581 struct psref psref_ia;
582
583 ifp = m_get_rcvif_psref(m, &psref);
584 if (ifp == NULL)
585 goto freeit;
586
587 if (ip6->ip6_hlim != 255) {
588 nd6log(LOG_ERR,
589 "invalid hlim (%d) from %s to %s on %s\n",
590 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src),
591 ip6_sprintf(&ip6->ip6_dst), if_name(ifp));
592 goto bad;
593 }
594
595 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len);
596 if (nd_na == NULL) {
597 m_put_rcvif_psref(ifp, &psref);
598 ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
599 return;
600 }
601
602 flags = nd_na->nd_na_flags_reserved;
603 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0);
604 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0);
605 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0);
606
607 taddr6 = nd_na->nd_na_target;
608 if (in6_setscope(&taddr6, ifp, NULL)) {
609 m_put_rcvif_psref(ifp, &psref);
610 return; /* XXX: impossible */
611 }
612
613 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
614 nd6log(LOG_ERR, "invalid target address %s\n",
615 ip6_sprintf(&taddr6));
616 goto bad;
617 }
618 if (is_solicited && IN6_IS_ADDR_MULTICAST(&daddr6)) {
619 nd6log(LOG_ERR, "a solicited adv is multicasted\n");
620 goto bad;
621 }
622
623 icmp6len -= sizeof(*nd_na);
624 nd6_option_init(nd_na + 1, icmp6len, &ndopts);
625 if (nd6_options(&ndopts) < 0) {
626 nd6log(LOG_INFO, "invalid ND option, ignored\n");
627 /* nd6_options have incremented stats */
628 goto freeit;
629 }
630
631 if (ndopts.nd_opts_tgt_lladdr) {
632 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
633 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
634 }
635
636 ifa = (struct ifaddr *)in6ifa_ifpwithaddr_psref(ifp, &taddr6, &psref_ia);
637
638 /*
639 * Target address matches one of my interface address.
640 *
641 * If my address is tentative, this means that there's somebody
642 * already using the same address as mine. This indicates DAD failure.
643 * This is defined in RFC 2462.
644 *
645 * Otherwise, process as defined in RFC 2461.
646 */
647 if (ifa
648 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) {
649 nd6_dad_na_input(ifa);
650 ifa_release(ifa, &psref_ia);
651 ifa = NULL;
652 goto freeit;
653 }
654
655 /* Just for safety, maybe unnecessary. */
656 if (ifa) {
657 log(LOG_ERR,
658 "nd6_na_input: duplicate IP6 address %s\n",
659 ip6_sprintf(&taddr6));
660 ifa_release(ifa, &psref_ia);
661 ifa = NULL;
662 goto freeit;
663 }
664
665 /*
666 * Make sure the source address is from a neighbor's address.
667 */
668 sockaddr_in6_init(&ssin6, &saddr6, 0, 0, 0);
669 if (nd6_is_addr_neighbor(&ssin6, ifp) == 0) {
670 nd6log(LOG_INFO, "ND packet from non-neighbor %s on %s\n",
671 ip6_sprintf(&saddr6), if_name(ifp));
672 goto bad;
673 }
674
675 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
676 nd6log(LOG_INFO, "lladdrlen mismatch for %s "
677 "(if %d, NA packet %d)\n", ip6_sprintf(&taddr6),
678 ifp->if_addrlen, lladdrlen - 2);
679 goto bad;
680 }
681
682 /*
683 * If no neighbor cache entry is found, NA SHOULD silently be
684 * discarded.
685 */
686 ln = nd6_lookup(&taddr6, ifp, true);
687 if (ln == NULL)
688 goto freeit;
689
690 rt_announce = 0;
691 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
692 /*
693 * If the link-layer has address, and no lladdr option came,
694 * discard the packet.
695 */
696 if (ifp->if_addrlen && !lladdr)
697 goto freeit;
698
699 /*
700 * Record link-layer address, and update the state.
701 */
702 memcpy(&ln->ll_addr, lladdr, ifp->if_addrlen);
703 ln->la_flags |= LLE_VALID;
704 rt_announce = 1;
705 if (is_solicited) {
706 ln->ln_state = ND6_LLINFO_REACHABLE;
707 ln->ln_byhint = 0;
708 if (!ND6_LLINFO_PERMANENT(ln)) {
709 nd6_llinfo_settimer(ln,
710 ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz);
711 }
712 } else {
713 ln->ln_state = ND6_LLINFO_STALE;
714 nd6_llinfo_settimer(ln, nd6_gctimer * hz);
715 }
716 if ((ln->ln_router = is_router) != 0) {
717 /*
718 * This means a router's state has changed from
719 * non-reachable to probably reachable, and might
720 * affect the status of associated prefixes..
721 */
722 checklink = true;
723 }
724 } else {
725 int llchange;
726
727 /*
728 * Check if the link-layer address has changed or not.
729 */
730 if (lladdr == NULL)
731 llchange = 0;
732 else {
733 if (ln->la_flags & LLE_VALID) {
734 if (memcmp(lladdr, &ln->ll_addr, ifp->if_addrlen))
735 llchange = rt_announce = 1;
736 else
737 llchange = 0;
738 } else
739 llchange = rt_announce = 1;
740 }
741
742 /*
743 * This is VERY complex. Look at it with care.
744 *
745 * override solicit lladdr llchange action
746 * (L: record lladdr)
747 *
748 * 0 0 n -- (2c)
749 * 0 0 y n (2b) L
750 * 0 0 y y (1) REACHABLE->STALE
751 * 0 1 n -- (2c) *->REACHABLE
752 * 0 1 y n (2b) L *->REACHABLE
753 * 0 1 y y (1) REACHABLE->STALE
754 * 1 0 n -- (2a)
755 * 1 0 y n (2a) L
756 * 1 0 y y (2a) L *->STALE
757 * 1 1 n -- (2a) *->REACHABLE
758 * 1 1 y n (2a) L *->REACHABLE
759 * 1 1 y y (2a) L *->REACHABLE
760 */
761 if (!is_override && lladdr != NULL && llchange) { /* (1) */
762 /*
763 * If state is REACHABLE, make it STALE.
764 * no other updates should be done.
765 */
766 if (ln->ln_state == ND6_LLINFO_REACHABLE) {
767 ln->ln_state = ND6_LLINFO_STALE;
768 nd6_llinfo_settimer(ln, nd6_gctimer * hz);
769 }
770 goto freeit;
771 } else if (is_override /* (2a) */
772 || (!is_override && lladdr != NULL && !llchange) /* (2b) */
773 || lladdr == NULL) { /* (2c) */
774 /*
775 * Update link-local address, if any.
776 */
777 if (lladdr != NULL) {
778 memcpy(&ln->ll_addr, lladdr, ifp->if_addrlen);
779 ln->la_flags |= LLE_VALID;
780 }
781
782 /*
783 * If solicited, make the state REACHABLE.
784 * If not solicited and the link-layer address was
785 * changed, make it STALE.
786 */
787 if (is_solicited) {
788 ln->ln_state = ND6_LLINFO_REACHABLE;
789 ln->ln_byhint = 0;
790 if (!ND6_LLINFO_PERMANENT(ln)) {
791 nd6_llinfo_settimer(ln,
792 ND_IFINFO(ifp)->reachable * hz);
793 }
794 } else {
795 if (lladdr && llchange) {
796 ln->ln_state = ND6_LLINFO_STALE;
797 nd6_llinfo_settimer(ln,
798 nd6_gctimer * hz);
799 }
800 }
801 }
802
803 if (ln->ln_router && !is_router) {
804 /*
805 * The peer dropped the router flag.
806 * Remove the sender from the Default Router List and
807 * update the Destination Cache entries.
808 */
809 struct nd_defrouter *dr;
810 const struct in6_addr *in6;
811 int s;
812
813 in6 = &ln->r_l3addr.addr6;
814
815 /*
816 * Lock to protect the default router list.
817 * XXX: this might be unnecessary, since this function
818 * is only called under the network software interrupt
819 * context. However, we keep it just for safety.
820 */
821 s = splsoftnet();
822 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp);
823 if (dr)
824 defrtrlist_del(dr, NULL);
825 else if (!ip6_forwarding) {
826 /*
827 * Even if the neighbor is not in the default
828 * router list, the neighbor may be used
829 * as a next hop for some destinations
830 * (e.g. redirect case). So we must
831 * call rt6_flush explicitly.
832 */
833 rt6_flush(&ip6->ip6_src, ln->lle_tbl->llt_ifp);
834 }
835 splx(s);
836 }
837 ln->ln_router = is_router;
838 }
839 /*
840 * XXX: does this matter?
841 * rt->rt_flags &= ~RTF_REJECT;
842 */
843 ln->ln_asked = 0;
844 nd6_llinfo_release_pkts(ln, ifp);
845 /* FIXME */
846#if 0
847 if (rt_announce) /* tell user process about any new lladdr */
848 rt_newmsg(RTM_CHANGE, rt);
849#endif
850
851 freeit:
852 if (ln != NULL)
853 LLE_WUNLOCK(ln);
854
855 if (checklink)
856 pfxlist_onlink_check();
857
858 m_put_rcvif_psref(ifp, &psref);
859 m_freem(m);
860 return;
861
862 bad:
863 if (ln != NULL)
864 LLE_WUNLOCK(ln);
865
866 ICMP6_STATINC(ICMP6_STAT_BADNA);
867 m_put_rcvif_psref(ifp, &psref);
868 m_freem(m);
869}
870
871/*
872 * Neighbor advertisement output handling.
873 *
874 * Based on RFC 2461
875 *
876 * the following items are not implemented yet:
877 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
878 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
879 */
880void
881nd6_na_output(
882 struct ifnet *ifp,
883 const struct in6_addr *daddr6_0,
884 const struct in6_addr *taddr6,
885 u_long flags,
886 int tlladdr, /* 1 if include target link-layer address */
887 const struct sockaddr *sdl0) /* sockaddr_dl (= proxy NA) or NULL */
888{
889 struct mbuf *m;
890 struct ip6_hdr *ip6;
891 struct nd_neighbor_advert *nd_na;
892 struct ip6_moptions im6o;
893 struct sockaddr *dst;
894 union {
895 struct sockaddr dst;
896 struct sockaddr_in6 dst6;
897 } u;
898 struct in6_addr daddr6;
899 int icmp6len, maxlen, error;
900 const void *mac;
901 struct route ro;
902
903 mac = NULL;
904 memset(&ro, 0, sizeof(ro));
905
906 daddr6 = *daddr6_0; /* make a local copy for modification */
907
908 /* estimate the size of message */
909 maxlen = sizeof(*ip6) + sizeof(*nd_na);
910 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
911#ifdef DIAGNOSTIC
912 if (max_linkhdr + maxlen >= MCLBYTES) {
913 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES "
914 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
915 panic("nd6_na_output: insufficient MCLBYTES");
916 /* NOTREACHED */
917 }
918#endif
919
920 MGETHDR(m, M_DONTWAIT, MT_DATA);
921 if (m && max_linkhdr + maxlen >= MHLEN) {
922 MCLGET(m, M_DONTWAIT);
923 if ((m->m_flags & M_EXT) == 0) {
924 m_free(m);
925 m = NULL;
926 }
927 }
928 if (m == NULL)
929 return;
930 m_reset_rcvif(m);
931
932 if (IN6_IS_ADDR_MULTICAST(&daddr6)) {
933 m->m_flags |= M_MCAST;
934 im6o.im6o_multicast_if_index = if_get_index(ifp);
935 im6o.im6o_multicast_hlim = 255;
936 im6o.im6o_multicast_loop = 0;
937 }
938
939 icmp6len = sizeof(*nd_na);
940 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len;
941 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
942
943 /* fill neighbor advertisement packet */
944 ip6 = mtod(m, struct ip6_hdr *);
945 ip6->ip6_flow = 0;
946 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
947 ip6->ip6_vfc |= IPV6_VERSION;
948 ip6->ip6_nxt = IPPROTO_ICMPV6;
949 ip6->ip6_hlim = 255;
950 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) {
951 /* reply to DAD */
952 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
953 daddr6.s6_addr16[1] = 0;
954 daddr6.s6_addr32[1] = 0;
955 daddr6.s6_addr32[2] = 0;
956 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE;
957 if (in6_setscope(&daddr6, ifp, NULL))
958 goto bad;
959
960 flags &= ~ND_NA_FLAG_SOLICITED;
961 }
962 ip6->ip6_dst = daddr6;
963 sockaddr_in6_init(&u.dst6, &daddr6, 0, 0, 0);
964 dst = &u.dst;
965 if (rtcache_setdst(&ro, dst) != 0)
966 goto bad;
967
968 /*
969 * Select a source whose scope is the same as that of the dest.
970 */
971 error = in6_selectsrc(satosin6(dst), NULL, NULL, &ro, NULL, NULL, NULL,
972 &ip6->ip6_src);
973 if (error != 0) {
974 nd6log(LOG_DEBUG, "source can't be "
975 "determined: dst=%s, error=%d\n",
976 ip6_sprintf(&satocsin6(dst)->sin6_addr), error);
977 goto bad;
978 }
979 nd_na = (struct nd_neighbor_advert *)(ip6 + 1);
980 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT;
981 nd_na->nd_na_code = 0;
982 nd_na->nd_na_target = *taddr6;
983 in6_clearscope(&nd_na->nd_na_target); /* XXX */
984
985 /*
986 * "tlladdr" indicates NS's condition for adding tlladdr or not.
987 * see nd6_ns_input() for details.
988 * Basically, if NS packet is sent to unicast/anycast addr,
989 * target lladdr option SHOULD NOT be included.
990 */
991 if (tlladdr) {
992 /*
993 * sdl0 != NULL indicates proxy NA. If we do proxy, use
994 * lladdr in sdl0. If we are not proxying (sending NA for
995 * my address) use lladdr configured for the interface.
996 */
997 if (sdl0 == NULL)
998 mac = nd6_ifptomac(ifp);
999 else if (sdl0->sa_family == AF_LINK) {
1000 const struct sockaddr_dl *sdl;
1001 sdl = satocsdl(sdl0);
1002 if (sdl->sdl_alen == ifp->if_addrlen)
1003 mac = CLLADDR(sdl);
1004 }
1005 }
1006 if (tlladdr && mac) {
1007 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
1008 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1);
1009
1010 /* roundup to 8 bytes alignment! */
1011 optlen = (optlen + 7) & ~7;
1012
1013 m->m_pkthdr.len += optlen;
1014 m->m_len += optlen;
1015 icmp6len += optlen;
1016 memset((void *)nd_opt, 0, optlen);
1017 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
1018 nd_opt->nd_opt_len = optlen >> 3;
1019 memcpy((void *)(nd_opt + 1), mac, ifp->if_addrlen);
1020 } else
1021 flags &= ~ND_NA_FLAG_OVERRIDE;
1022
1023 ip6->ip6_plen = htons((u_int16_t)icmp6len);
1024 nd_na->nd_na_flags_reserved = flags;
1025 nd_na->nd_na_cksum = 0;
1026 nd_na->nd_na_cksum =
1027 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len);
1028
1029 ip6_output(m, NULL, NULL, 0, &im6o, NULL, NULL);
1030
1031 icmp6_ifstat_inc(ifp, ifs6_out_msg);
1032 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert);
1033 ICMP6_STATINC(ICMP6_STAT_OUTHIST + ND_NEIGHBOR_ADVERT);
1034
1035 rtcache_free(&ro);
1036 return;
1037
1038 bad:
1039 rtcache_free(&ro);
1040 m_freem(m);
1041 return;
1042}
1043
1044const void *
1045nd6_ifptomac(const 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 case IFT_PROPVIRTUAL:
1053 case IFT_CARP:
1054 case IFT_L2VLAN:
1055 case IFT_IEEE80211:
1056 return CLLADDR(ifp->if_sadl);
1057 default:
1058 return NULL;
1059 }
1060}
1061
1062TAILQ_HEAD(dadq_head, dadq);
1063struct dadq {
1064 TAILQ_ENTRY(dadq) dad_list;
1065 struct ifaddr *dad_ifa;
1066 int dad_count; /* max NS to send */
1067 int dad_ns_tcount; /* # of trials to send NS */
1068 int dad_ns_ocount; /* NS sent so far */
1069 int dad_ns_icount;
1070 int dad_na_icount;
1071 struct callout dad_timer_ch;
1072};
1073
1074static struct dadq_head dadq;
1075static int dad_init = 0;
1076static kmutex_t nd6_dad_lock;
1077
1078static struct dadq *
1079nd6_dad_find(struct ifaddr *ifa)
1080{
1081 struct dadq *dp;
1082
1083 KASSERT(mutex_owned(&nd6_dad_lock));
1084
1085 TAILQ_FOREACH(dp, &dadq, dad_list) {
1086 if (dp->dad_ifa == ifa)
1087 return dp;
1088 }
1089 return NULL;
1090}
1091
1092static void
1093nd6_dad_starttimer(struct dadq *dp, int ticks)
1094{
1095
1096 callout_reset(&dp->dad_timer_ch, ticks,
1097 (void (*)(void *))nd6_dad_timer, (void *)dp->dad_ifa);
1098}
1099
1100static void
1101nd6_dad_stoptimer(struct dadq *dp)
1102{
1103
1104#ifdef NET_MPSAFE
1105 callout_halt(&dp->dad_timer_ch, NULL);
1106#else
1107 callout_halt(&dp->dad_timer_ch, softnet_lock);
1108#endif
1109}
1110
1111/*
1112 * Start Duplicate Address Detection (DAD) for specified interface address.
1113 *
1114 * Note that callout is used when xtick > 0 and not when xtick == 0.
1115 *
1116 * xtick: minimum delay ticks for IFF_UP event
1117 */
1118void
1119nd6_dad_start(struct ifaddr *ifa, int xtick)
1120{
1121 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1122 struct dadq *dp;
1123
1124 if (!dad_init) {
1125 TAILQ_INIT(&dadq);
1126 mutex_init(&nd6_dad_lock, MUTEX_DEFAULT, IPL_NONE);
1127 dad_init++;
1128 }
1129
1130 /*
1131 * If we don't need DAD, don't do it.
1132 * There are several cases:
1133 * - DAD is disabled (ip6_dad_count == 0)
1134 * - the interface address is anycast
1135 */
1136 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
1137 log(LOG_DEBUG,
1138 "nd6_dad_start: called with non-tentative address "
1139 "%s(%s)\n",
1140 ip6_sprintf(&ia->ia_addr.sin6_addr),
1141 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1142 return;
1143 }
1144 if (ia->ia6_flags & IN6_IFF_ANYCAST || !ip6_dad_count) {
1145 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1146 rt_newaddrmsg(RTM_NEWADDR, ifa, 0, NULL);
1147 return;
1148 }
1149 KASSERT(ifa->ifa_ifp != NULL);
1150 if (!(ifa->ifa_ifp->if_flags & IFF_UP))
1151 return;
1152
1153 mutex_enter(&nd6_dad_lock);
1154 if (nd6_dad_find(ifa) != NULL) {
1155 mutex_exit(&nd6_dad_lock);
1156 /* DAD already in progress */
1157 return;
1158 }
1159
1160 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT);
1161 if (dp == NULL) {
1162 mutex_exit(&nd6_dad_lock);
1163 log(LOG_ERR, "nd6_dad_start: memory allocation failed for "
1164 "%s(%s)\n",
1165 ip6_sprintf(&ia->ia_addr.sin6_addr),
1166 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1167 return;
1168 }
1169 memset(dp, 0, sizeof(*dp));
1170 callout_init(&dp->dad_timer_ch, CALLOUT_MPSAFE);
1171
1172 /*
1173 * Send NS packet for DAD, ip6_dad_count times.
1174 * Note that we must delay the first transmission, if this is the
1175 * first packet to be sent from the interface after interface
1176 * (re)initialization.
1177 */
1178 dp->dad_ifa = ifa;
1179 ifaref(ifa); /* just for safety */
1180 dp->dad_count = ip6_dad_count;
1181 dp->dad_ns_icount = dp->dad_na_icount = 0;
1182 dp->dad_ns_ocount = dp->dad_ns_tcount = 0;
1183 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list);
1184
1185 nd6log(LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp),
1186 ip6_sprintf(&ia->ia_addr.sin6_addr));
1187
1188 if (xtick == 0) {
1189 nd6_dad_ns_output(dp, ifa);
1190 nd6_dad_starttimer(dp,
1191 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1192 } else
1193 nd6_dad_starttimer(dp, xtick);
1194 mutex_exit(&nd6_dad_lock);
1195}
1196
1197/*
1198 * terminate DAD unconditionally. used for address removals.
1199 */
1200void
1201nd6_dad_stop(struct ifaddr *ifa)
1202{
1203 struct dadq *dp;
1204
1205 if (!dad_init)
1206 return;
1207
1208 mutex_enter(&nd6_dad_lock);
1209 dp = nd6_dad_find(ifa);
1210 if (dp == NULL) {
1211 mutex_exit(&nd6_dad_lock);
1212 /* DAD wasn't started yet */
1213 return;
1214 }
1215
1216 /* Prevent the timer from running anymore. */
1217 TAILQ_REMOVE(&dadq, dp, dad_list);
1218 mutex_exit(&nd6_dad_lock);
1219
1220 nd6_dad_stoptimer(dp);
1221
1222 free(dp, M_IP6NDP);
1223 dp = NULL;
1224 ifafree(ifa);
1225}
1226
1227static void
1228nd6_dad_timer(struct ifaddr *ifa)
1229{
1230 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1231 struct dadq *dp;
1232 int duplicate = 0;
1233
1234#ifndef NET_MPSAFE
1235 mutex_enter(softnet_lock);
1236 KERNEL_LOCK(1, NULL);
1237#endif
1238 mutex_enter(&nd6_dad_lock);
1239
1240 /* Sanity check */
1241 if (ia == NULL) {
1242 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n");
1243 goto done;
1244 }
1245 dp = nd6_dad_find(ifa);
1246 if (dp == NULL) {
1247 /* DAD seems to be stopping, so do nothing. */
1248 goto done;
1249 }
1250 if (ia->ia6_flags & IN6_IFF_DUPLICATED) {
1251 log(LOG_ERR, "nd6_dad_timer: called with duplicate address "
1252 "%s(%s)\n",
1253 ip6_sprintf(&ia->ia_addr.sin6_addr),
1254 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1255 goto done;
1256 }
1257 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) {
1258 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address "
1259 "%s(%s)\n",
1260 ip6_sprintf(&ia->ia_addr.sin6_addr),
1261 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1262 goto done;
1263 }
1264
1265 /* timeouted with IFF_{RUNNING,UP} check */
1266 if (dp->dad_ns_tcount > dad_maxtry) {
1267 nd6log(LOG_INFO, "%s: could not run DAD, driver problem?\n",
1268 if_name(ifa->ifa_ifp));
1269
1270 TAILQ_REMOVE(&dadq, dp, dad_list);
1271 free(dp, M_IP6NDP);
1272 dp = NULL;
1273 ifafree(ifa);
1274 goto done;
1275 }
1276
1277 /* Need more checks? */
1278 if (dp->dad_ns_ocount < dp->dad_count) {
1279 /*
1280 * We have more NS to go. Send NS packet for DAD.
1281 */
1282 nd6_dad_ns_output(dp, ifa);
1283 nd6_dad_starttimer(dp,
1284 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1285 } else {
1286 /*
1287 * We have transmitted sufficient number of DAD packets.
1288 * See what we've got.
1289 */
1290 if (dp->dad_na_icount) {
1291 /*
1292 * the check is in nd6_dad_na_input(),
1293 * but just in case
1294 */
1295 duplicate++;
1296 }
1297
1298 if (dp->dad_ns_icount) {
1299 /* We've seen NS, means DAD has failed. */
1300 duplicate++;
1301 }
1302
1303 if (duplicate) {
1304 /* (*dp) will be freed in nd6_dad_duplicated() */
1305 dp = NULL;
1306 } else {
1307 /*
1308 * We are done with DAD. No NA came, no NS came.
1309 * No duplicate address found.
1310 */
1311 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1312 rt_newaddrmsg(RTM_NEWADDR, ifa, 0, NULL);
1313
1314 nd6log(LOG_DEBUG,
1315 "%s: DAD complete for %s - no duplicates found\n",
1316 if_name(ifa->ifa_ifp),
1317 ip6_sprintf(&ia->ia_addr.sin6_addr));
1318
1319 TAILQ_REMOVE(&dadq, dp, dad_list);
1320 free(dp, M_IP6NDP);
1321 dp = NULL;
1322 ifafree(ifa);
1323 }
1324 }
1325
1326done:
1327 mutex_exit(&nd6_dad_lock);
1328
1329 if (duplicate)
1330 nd6_dad_duplicated(ifa);
1331
1332#ifndef NET_MPSAFE
1333 KERNEL_UNLOCK_ONE(NULL);
1334 mutex_exit(softnet_lock);
1335#endif
1336}
1337
1338void
1339nd6_dad_duplicated(struct ifaddr *ifa)
1340{
1341 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1342 struct ifnet *ifp;
1343 struct dadq *dp;
1344
1345 mutex_enter(&nd6_dad_lock);
1346 dp = nd6_dad_find(ifa);
1347 if (dp == NULL) {
1348 mutex_exit(&nd6_dad_lock);
1349 /* DAD seems to be stopping, so do nothing. */
1350 return;
1351 }
1352
1353 ifp = ifa->ifa_ifp;
1354 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: "
1355 "NS in/out=%d/%d, NA in=%d\n",
1356 if_name(ifp), ip6_sprintf(&ia->ia_addr.sin6_addr),
1357 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount);
1358
1359 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1360 ia->ia6_flags |= IN6_IFF_DUPLICATED;
1361
1362 /* We are done with DAD, with duplicated address found. (failure) */
1363 nd6_dad_stoptimer(dp);
1364
1365 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n",
1366 if_name(ifp), ip6_sprintf(&ia->ia_addr.sin6_addr));
1367 log(LOG_ERR, "%s: manual intervention required\n",
1368 if_name(ifp));
1369
1370 /* Inform the routing socket that DAD has completed */
1371 rt_newaddrmsg(RTM_NEWADDR, ifa, 0, NULL);
1372
1373 /*
1374 * If the address is a link-local address formed from an interface
1375 * identifier based on the hardware address which is supposed to be
1376 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP
1377 * operation on the interface SHOULD be disabled.
1378 * [rfc2462bis-03 Section 5.4.5]
1379 */
1380 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) {
1381 struct in6_addr in6;
1382
1383 /*
1384 * To avoid over-reaction, we only apply this logic when we are
1385 * very sure that hardware addresses are supposed to be unique.
1386 */
1387 switch (ifp->if_type) {
1388 case IFT_ETHER:
1389 case IFT_FDDI:
1390 case IFT_ATM:
1391 case IFT_IEEE1394:
1392#ifdef IFT_IEEE80211
1393 case IFT_IEEE80211:
1394#endif
1395 in6 = ia->ia_addr.sin6_addr;
1396 if (in6_get_hw_ifid(ifp, &in6) == 0 &&
1397 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) {
1398 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED;
1399 log(LOG_ERR, "%s: possible hardware address "
1400 "duplication detected, disable IPv6\n",
1401 if_name(ifp));
1402 }
1403 break;
1404 }
1405 }
1406
1407 TAILQ_REMOVE(&dadq, dp, dad_list);
1408 mutex_exit(&nd6_dad_lock);
1409
1410 free(dp, M_IP6NDP);
1411 dp = NULL;
1412 ifafree(ifa);
1413}
1414
1415static void
1416nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa)
1417{
1418 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1419 struct ifnet *ifp = ifa->ifa_ifp;
1420
1421 dp->dad_ns_tcount++;
1422 if ((ifp->if_flags & IFF_UP) == 0) {
1423#if 0
1424 printf("%s: interface down?\n", if_name(ifp));
1425#endif
1426 return;
1427 }
1428 if ((ifp->if_flags & IFF_RUNNING) == 0) {
1429#if 0
1430 printf("%s: interface not running?\n", if_name(ifp));
1431#endif
1432 return;
1433 }
1434
1435 dp->dad_ns_tcount = 0;
1436 dp->dad_ns_ocount++;
1437 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1);
1438}
1439
1440static void
1441nd6_dad_ns_input(struct ifaddr *ifa)
1442{
1443 struct in6_ifaddr *ia;
1444 const struct in6_addr *taddr6;
1445 struct dadq *dp;
1446 int duplicate;
1447
1448 if (ifa == NULL)
1449 panic("ifa == NULL in nd6_dad_ns_input");
1450
1451 ia = (struct in6_ifaddr *)ifa;
1452 taddr6 = &ia->ia_addr.sin6_addr;
1453 duplicate = 0;
1454
1455 mutex_enter(&nd6_dad_lock);
1456 dp = nd6_dad_find(ifa);
1457
1458 /* Quickhack - completely ignore DAD NS packets */
1459 if (dad_ignore_ns) {
1460 nd6log(LOG_INFO, "ignoring DAD NS packet for "
1461 "address %s(%s)\n", ip6_sprintf(taddr6),
1462 if_name(ifa->ifa_ifp));
1463 return;
1464 }
1465
1466 /*
1467 * if I'm yet to start DAD, someone else started using this address
1468 * first. I have a duplicate and you win.
1469 */
1470 if (dp == NULL || dp->dad_ns_ocount == 0)
1471 duplicate++;
1472
1473 /* XXX more checks for loopback situation - see nd6_dad_timer too */
1474
1475 if (duplicate) {
1476 dp = NULL; /* will be freed in nd6_dad_duplicated() */
1477 mutex_exit(&nd6_dad_lock);
1478 nd6_dad_duplicated(ifa);
1479 } else {
1480 /*
1481 * not sure if I got a duplicate.
1482 * increment ns count and see what happens.
1483 */
1484 if (dp)
1485 dp->dad_ns_icount++;
1486 mutex_exit(&nd6_dad_lock);
1487 }
1488}
1489
1490static void
1491nd6_dad_na_input(struct ifaddr *ifa)
1492{
1493 struct dadq *dp;
1494
1495 if (ifa == NULL)
1496 panic("ifa == NULL in nd6_dad_na_input");
1497
1498 mutex_enter(&nd6_dad_lock);
1499 dp = nd6_dad_find(ifa);
1500 if (dp)
1501 dp->dad_na_icount++;
1502 mutex_exit(&nd6_dad_lock);
1503
1504 /* remove the address. */
1505 nd6_dad_duplicated(ifa);
1506}
1507