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/9.2/sys/netinet6/nd6_nbr.c 252555 2013-07-03 09:25:29Z np $");
34
35 #include "opt_inet.h"
36 #include "opt_inet6.h"
37 #include "opt_ipsec.h"
38 #include "opt_mpath.h"
39
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/malloc.h>
43 #include <sys/lock.h>
44 #include <sys/rwlock.h>
45 #include <sys/mbuf.h>
46 #include <sys/socket.h>
47 #include <sys/sockio.h>
48 #include <sys/time.h>
49 #include <sys/kernel.h>
50 #include <sys/errno.h>
51 #include <sys/syslog.h>
52 #include <sys/queue.h>
53 #include <sys/callout.h>
54
55 #include <net/if.h>
56 #include <net/if_types.h>
57 #include <net/if_dl.h>
58 #include <net/if_var.h>
59 #include <net/route.h>
60 #ifdef RADIX_MPATH
61 #include <net/radix_mpath.h>
62 #endif
63
64 #include <netinet/in.h>
65 #include <netinet/in_var.h>
66 #include <net/if_llatbl.h>
67 #define L3_ADDR_SIN6(le) ((struct sockaddr_in6 *) L3_ADDR(le))
68 #include <netinet6/in6_var.h>
69 #include <netinet6/in6_ifattach.h>
70 #include <netinet/ip6.h>
71 #include <netinet6/ip6_var.h>
72 #include <netinet6/scope6_var.h>
73 #include <netinet6/nd6.h>
74 #include <netinet/icmp6.h>
75 #include <netinet/ip_carp.h>
76 #include <netinet6/send.h>
77
78 #define SDL(s) ((struct sockaddr_dl *)s)
79
80 struct dadq;
81 static struct dadq *nd6_dad_find(struct ifaddr *);
82 static void nd6_dad_starttimer(struct dadq *, int);
83 static void nd6_dad_stoptimer(struct dadq *);
84 static void nd6_dad_timer(struct dadq *);
85 static void nd6_dad_ns_output(struct dadq *, struct ifaddr *);
86 static void nd6_dad_ns_input(struct ifaddr *);
87 static void nd6_dad_na_input(struct ifaddr *);
88 static void nd6_na_output_fib(struct ifnet *, const struct in6_addr *,
89 const struct in6_addr *, u_long, int, struct sockaddr *, u_int);
90
91 VNET_DEFINE(int, dad_ignore_ns) = 0; /* ignore NS in DAD - specwise incorrect*/
92 VNET_DEFINE(int, dad_maxtry) = 15; /* max # of *tries* to transmit DAD packet */
93 #define V_dad_ignore_ns VNET(dad_ignore_ns)
94 #define V_dad_maxtry VNET(dad_maxtry)
95
96 /*
97 * Input a Neighbor Solicitation Message.
98 *
99 * Based on RFC 2461
100 * Based on RFC 2462 (duplicate address detection)
101 */
102 void
103 nd6_ns_input(struct mbuf *m, int off, int icmp6len)
104 {
105 struct ifnet *ifp = m->m_pkthdr.rcvif;
106 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
107 struct nd_neighbor_solicit *nd_ns;
108 struct in6_addr saddr6 = ip6->ip6_src;
109 struct in6_addr daddr6 = ip6->ip6_dst;
110 struct in6_addr taddr6;
111 struct in6_addr myaddr6;
112 char *lladdr = NULL;
113 struct ifaddr *ifa = NULL;
114 int lladdrlen = 0;
115 int anycast = 0, proxy = 0, tentative = 0;
116 int tlladdr;
117 int rflag;
118 union nd_opts ndopts;
119 struct sockaddr_dl proxydl;
120 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
121
122 rflag = (V_ip6_forwarding) ? ND_NA_FLAG_ROUTER : 0;
123 if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV && V_ip6_norbit_raif)
124 rflag = 0;
125 #ifndef PULLDOWN_TEST
126 IP6_EXTHDR_CHECK(m, off, icmp6len,);
127 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off);
128 #else
129 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len);
130 if (nd_ns == NULL) {
131 ICMP6STAT_INC(icp6s_tooshort);
132 return;
133 }
134 #endif
135 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */
136 taddr6 = nd_ns->nd_ns_target;
137 if (in6_setscope(&taddr6, ifp, NULL) != 0)
138 goto bad;
139
140 if (ip6->ip6_hlim != 255) {
141 nd6log((LOG_ERR,
142 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n",
143 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
144 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
145 goto bad;
146 }
147
148 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
149 /* dst has to be a solicited node multicast address. */
150 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL &&
151 /* don't check ifindex portion */
152 daddr6.s6_addr32[1] == 0 &&
153 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE &&
154 daddr6.s6_addr8[12] == 0xff) {
155 ; /* good */
156 } else {
157 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
158 "(wrong ip6 dst)\n"));
159 goto bad;
160 }
161 } else if (!V_nd6_onlink_ns_rfc4861) {
162 struct sockaddr_in6 src_sa6;
163
164 /*
165 * According to recent IETF discussions, it is not a good idea
166 * to accept a NS from an address which would not be deemed
167 * to be a neighbor otherwise. This point is expected to be
168 * clarified in future revisions of the specification.
169 */
170 bzero(&src_sa6, sizeof(src_sa6));
171 src_sa6.sin6_family = AF_INET6;
172 src_sa6.sin6_len = sizeof(src_sa6);
173 src_sa6.sin6_addr = saddr6;
174 if (nd6_is_addr_neighbor(&src_sa6, ifp) == 0) {
175 nd6log((LOG_INFO, "nd6_ns_input: "
176 "NS packet from non-neighbor\n"));
177 goto bad;
178 }
179 }
180
181 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
182 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n"));
183 goto bad;
184 }
185
186 icmp6len -= sizeof(*nd_ns);
187 nd6_option_init(nd_ns + 1, icmp6len, &ndopts);
188 if (nd6_options(&ndopts) < 0) {
189 nd6log((LOG_INFO,
190 "nd6_ns_input: invalid ND option, ignored\n"));
191 /* nd6_options have incremented stats */
192 goto freeit;
193 }
194
195 if (ndopts.nd_opts_src_lladdr) {
196 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
197 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
198 }
199
200 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) {
201 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet "
202 "(link-layer address option)\n"));
203 goto bad;
204 }
205
206 /*
207 * Attaching target link-layer address to the NA?
208 * (RFC 2461 7.2.4)
209 *
210 * NS IP dst is unicast/anycast MUST NOT add
211 * NS IP dst is solicited-node multicast MUST add
212 *
213 * In implementation, we add target link-layer address by default.
214 * We do not add one in MUST NOT cases.
215 */
216 if (!IN6_IS_ADDR_MULTICAST(&daddr6))
217 tlladdr = 0;
218 else
219 tlladdr = 1;
220
221 /*
222 * Target address (taddr6) must be either:
223 * (1) Valid unicast/anycast address for my receiving interface,
224 * (2) Unicast address for which I'm offering proxy service, or
225 * (3) "tentative" address on which DAD is being performed.
226 */
227 /* (1) and (3) check. */
228 if (ifp->if_carp)
229 ifa = (*carp_iamatch6_p)(ifp, &taddr6);
230 if (ifa == NULL)
231 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
232
233 /* (2) check. */
234 if (ifa == NULL) {
235 struct rtentry *rt;
236 struct sockaddr_in6 tsin6;
237 int need_proxy;
238 #ifdef RADIX_MPATH
239 struct route_in6 ro;
240 #endif
241
242 bzero(&tsin6, sizeof tsin6);
243 tsin6.sin6_len = sizeof(struct sockaddr_in6);
244 tsin6.sin6_family = AF_INET6;
245 tsin6.sin6_addr = taddr6;
246
247 /* Always use the default FIB. */
248 #ifdef RADIX_MPATH
249 bzero(&ro, sizeof(ro));
250 ro.ro_dst = tsin6;
251 rtalloc_mpath_fib((struct route *)&ro, RTF_ANNOUNCE,
252 RT_DEFAULT_FIB);
253 rt = ro.ro_rt;
254 #else
255 rt = in6_rtalloc1((struct sockaddr *)&tsin6, 0, 0,
256 RT_DEFAULT_FIB);
257 #endif
258 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 &&
259 rt->rt_gateway->sa_family == AF_LINK);
260 if (rt != NULL) {
261 /*
262 * Make a copy while we can be sure that rt_gateway
263 * is still stable before unlocking to avoid lock
264 * order problems. proxydl will only be used if
265 * proxy will be set in the next block.
266 */
267 if (need_proxy)
268 proxydl = *SDL(rt->rt_gateway);
269 RTFREE_LOCKED(rt);
270 }
271 if (need_proxy) {
272 /*
273 * proxy NDP for single entry
274 */
275 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp,
276 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
277 if (ifa)
278 proxy = 1;
279 }
280 }
281 if (ifa == NULL) {
282 /*
283 * We've got an NS packet, and we don't have that adddress
284 * assigned for us. We MUST silently ignore it.
285 * See RFC2461 7.2.3.
286 */
287 goto freeit;
288 }
289 myaddr6 = *IFA_IN6(ifa);
290 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST;
291 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE;
292 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED)
293 goto freeit;
294
295 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
296 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s "
297 "(if %d, NS packet %d)\n",
298 ip6_sprintf(ip6bufs, &taddr6),
299 ifp->if_addrlen, lladdrlen - 2));
300 goto bad;
301 }
302
303 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) {
304 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n",
305 ip6_sprintf(ip6bufs, &saddr6)));
306 goto freeit;
307 }
308
309 /*
310 * We have neighbor solicitation packet, with target address equals to
311 * one of my tentative address.
312 *
313 * src addr how to process?
314 * --- ---
315 * multicast of course, invalid (rejected in ip6_input)
316 * unicast somebody is doing address resolution -> ignore
317 * unspec dup address detection
318 *
319 * The processing is defined in RFC 2462.
320 */
321 if (tentative) {
322 /*
323 * If source address is unspecified address, it is for
324 * duplicate address detection.
325 *
326 * If not, the packet is for addess resolution;
327 * silently ignore it.
328 */
329 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6))
330 nd6_dad_ns_input(ifa);
331
332 goto freeit;
333 }
334
335 /*
336 * If the source address is unspecified address, entries must not
337 * be created or updated.
338 * It looks that sender is performing DAD. Output NA toward
339 * all-node multicast address, to tell the sender that I'm using
340 * the address.
341 * S bit ("solicited") must be zero.
342 */
343 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
344 struct in6_addr in6_all;
345
346 in6_all = in6addr_linklocal_allnodes;
347 if (in6_setscope(&in6_all, ifp, NULL) != 0)
348 goto bad;
349 nd6_na_output_fib(ifp, &in6_all, &taddr6,
350 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
351 rflag, tlladdr, proxy ? (struct sockaddr *)&proxydl : NULL,
352 M_GETFIB(m));
353 goto freeit;
354 }
355
356 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen,
357 ND_NEIGHBOR_SOLICIT, 0);
358
359 nd6_na_output_fib(ifp, &saddr6, &taddr6,
360 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
361 rflag | ND_NA_FLAG_SOLICITED, tlladdr,
362 proxy ? (struct sockaddr *)&proxydl : NULL, M_GETFIB(m));
363 freeit:
364 if (ifa != NULL)
365 ifa_free(ifa);
366 m_freem(m);
367 return;
368
369 bad:
370 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n",
371 ip6_sprintf(ip6bufs, &saddr6)));
372 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n",
373 ip6_sprintf(ip6bufs, &daddr6)));
374 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n",
375 ip6_sprintf(ip6bufs, &taddr6)));
376 ICMP6STAT_INC(icp6s_badns);
377 if (ifa != NULL)
378 ifa_free(ifa);
379 m_freem(m);
380 }
381
382 /*
383 * Output a Neighbor Solicitation Message. Caller specifies:
384 * - ICMP6 header source IP6 address
385 * - ND6 header target IP6 address
386 * - ND6 header source datalink address
387 *
388 * Based on RFC 2461
389 * Based on RFC 2462 (duplicate address detection)
390 *
391 * ln - for source address determination
392 * dad - duplicate address detection
393 */
394 void
395 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6,
396 const struct in6_addr *taddr6, struct llentry *ln, int dad)
397 {
398 struct mbuf *m;
399 struct m_tag *mtag;
400 struct ip6_hdr *ip6;
401 struct nd_neighbor_solicit *nd_ns;
402 struct ip6_moptions im6o;
403 int icmp6len;
404 int maxlen;
405 caddr_t mac;
406 struct route_in6 ro;
407
408 if (IN6_IS_ADDR_MULTICAST(taddr6))
409 return;
410
411 /* estimate the size of message */
412 maxlen = sizeof(*ip6) + sizeof(*nd_ns);
413 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
414 if (max_linkhdr + maxlen >= MCLBYTES) {
415 #ifdef DIAGNOSTIC
416 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES "
417 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
418 #endif
419 return;
420 }
421
422 MGETHDR(m, M_DONTWAIT, MT_DATA);
423 if (m && max_linkhdr + maxlen >= MHLEN) {
424 MCLGET(m, M_DONTWAIT);
425 if ((m->m_flags & M_EXT) == 0) {
426 m_free(m);
427 m = NULL;
428 }
429 }
430 if (m == NULL)
431 return;
432 m->m_pkthdr.rcvif = NULL;
433
434 bzero(&ro, sizeof(ro));
435
436 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) {
437 m->m_flags |= M_MCAST;
438 im6o.im6o_multicast_ifp = ifp;
439 im6o.im6o_multicast_hlim = 255;
440 im6o.im6o_multicast_loop = 0;
441 }
442
443 icmp6len = sizeof(*nd_ns);
444 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len;
445 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
446
447 /* fill neighbor solicitation packet */
448 ip6 = mtod(m, struct ip6_hdr *);
449 ip6->ip6_flow = 0;
450 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
451 ip6->ip6_vfc |= IPV6_VERSION;
452 /* ip6->ip6_plen will be set later */
453 ip6->ip6_nxt = IPPROTO_ICMPV6;
454 ip6->ip6_hlim = 255;
455 if (daddr6)
456 ip6->ip6_dst = *daddr6;
457 else {
458 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
459 ip6->ip6_dst.s6_addr16[1] = 0;
460 ip6->ip6_dst.s6_addr32[1] = 0;
461 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE;
462 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3];
463 ip6->ip6_dst.s6_addr8[12] = 0xff;
464 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0)
465 goto bad;
466 }
467 if (!dad) {
468 struct ifaddr *ifa;
469
470 /*
471 * RFC2461 7.2.2:
472 * "If the source address of the packet prompting the
473 * solicitation is the same as one of the addresses assigned
474 * to the outgoing interface, that address SHOULD be placed
475 * in the IP Source Address of the outgoing solicitation.
476 * Otherwise, any one of the addresses assigned to the
477 * interface should be used."
478 *
479 * We use the source address for the prompting packet
480 * (saddr6), if:
481 * - saddr6 is given from the caller (by giving "ln"), and
482 * - saddr6 belongs to the outgoing interface.
483 * Otherwise, we perform the source address selection as usual.
484 */
485 struct in6_addr *hsrc;
486
487 hsrc = NULL;
488 if (ln != NULL) {
489 LLE_RLOCK(ln);
490 if (ln->la_hold != NULL) {
491 struct ip6_hdr *hip6; /* hold ip6 */
492
493 /*
494 * assuming every packet in la_hold has the same IP
495 * header
496 */
497 hip6 = mtod(ln->la_hold, struct ip6_hdr *);
498 /* XXX pullup? */
499 if (sizeof(*hip6) < ln->la_hold->m_len) {
500 ip6->ip6_src = hip6->ip6_src;
501 hsrc = &hip6->ip6_src;
502 }
503 }
504 LLE_RUNLOCK(ln);
505 }
506 if (hsrc && (ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp,
507 hsrc)) != NULL) {
508 /* ip6_src set already. */
509 ifa_free(ifa);
510 } else {
511 int error;
512 struct sockaddr_in6 dst_sa;
513 struct in6_addr src_in;
514 struct ifnet *oifp;
515
516 bzero(&dst_sa, sizeof(dst_sa));
517 dst_sa.sin6_family = AF_INET6;
518 dst_sa.sin6_len = sizeof(dst_sa);
519 dst_sa.sin6_addr = ip6->ip6_dst;
520
521 oifp = ifp;
522 error = in6_selectsrc(&dst_sa, NULL,
523 NULL, &ro, NULL, &oifp, &src_in);
524 if (error) {
525 char ip6buf[INET6_ADDRSTRLEN];
526 nd6log((LOG_DEBUG,
527 "nd6_ns_output: source can't be "
528 "determined: dst=%s, error=%d\n",
529 ip6_sprintf(ip6buf, &dst_sa.sin6_addr),
530 error));
531 goto bad;
532 }
533 ip6->ip6_src = src_in;
534 }
535 } else {
536 /*
537 * Source address for DAD packet must always be IPv6
538 * unspecified address. (0::0)
539 * We actually don't have to 0-clear the address (we did it
540 * above), but we do so here explicitly to make the intention
541 * clearer.
542 */
543 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src));
544 }
545 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1);
546 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT;
547 nd_ns->nd_ns_code = 0;
548 nd_ns->nd_ns_reserved = 0;
549 nd_ns->nd_ns_target = *taddr6;
550 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */
551
552 /*
553 * Add source link-layer address option.
554 *
555 * spec implementation
556 * --- ---
557 * DAD packet MUST NOT do not add the option
558 * there's no link layer address:
559 * impossible do not add the option
560 * there's link layer address:
561 * Multicast NS MUST add one add the option
562 * Unicast NS SHOULD add one add the option
563 */
564 if (!dad && (mac = nd6_ifptomac(ifp))) {
565 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
566 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
567 /* 8 byte alignments... */
568 optlen = (optlen + 7) & ~7;
569
570 m->m_pkthdr.len += optlen;
571 m->m_len += optlen;
572 icmp6len += optlen;
573 bzero((caddr_t)nd_opt, optlen);
574 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR;
575 nd_opt->nd_opt_len = optlen >> 3;
576 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
577 }
578
579 ip6->ip6_plen = htons((u_short)icmp6len);
580 nd_ns->nd_ns_cksum = 0;
581 nd_ns->nd_ns_cksum =
582 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len);
583
584 if (send_sendso_input_hook != NULL) {
585 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING,
586 sizeof(unsigned short), M_NOWAIT);
587 if (mtag == NULL)
588 goto bad;
589 *(unsigned short *)(mtag + 1) = nd_ns->nd_ns_type;
590 m_tag_prepend(m, mtag);
591 }
592
593 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL);
594 icmp6_ifstat_inc(ifp, ifs6_out_msg);
595 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit);
596 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_SOLICIT]);
597
598 /* We don't cache this route. */
599 RO_RTFREE(&ro);
600
601 return;
602
603 bad:
604 if (ro.ro_rt) {
605 RTFREE(ro.ro_rt);
606 }
607 m_freem(m);
608 return;
609 }
610
611 /*
612 * Neighbor advertisement input handling.
613 *
614 * Based on RFC 2461
615 * Based on RFC 2462 (duplicate address detection)
616 *
617 * the following items are not implemented yet:
618 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
619 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
620 */
621 void
622 nd6_na_input(struct mbuf *m, int off, int icmp6len)
623 {
624 struct ifnet *ifp = m->m_pkthdr.rcvif;
625 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
626 struct nd_neighbor_advert *nd_na;
627 struct in6_addr daddr6 = ip6->ip6_dst;
628 struct in6_addr taddr6;
629 int flags;
630 int is_router;
631 int is_solicited;
632 int is_override;
633 char *lladdr = NULL;
634 int lladdrlen = 0;
635 int checklink = 0;
636 struct ifaddr *ifa;
637 struct llentry *ln = NULL;
638 union nd_opts ndopts;
639 struct mbuf *chain = NULL;
640 struct m_tag *mtag;
641 struct sockaddr_in6 sin6;
642 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
643
644 if (ip6->ip6_hlim != 255) {
645 nd6log((LOG_ERR,
646 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n",
647 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
648 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
649 goto bad;
650 }
651
652 #ifndef PULLDOWN_TEST
653 IP6_EXTHDR_CHECK(m, off, icmp6len,);
654 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off);
655 #else
656 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len);
657 if (nd_na == NULL) {
658 ICMP6STAT_INC(icp6s_tooshort);
659 return;
660 }
661 #endif
662
663 flags = nd_na->nd_na_flags_reserved;
664 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0);
665 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0);
666 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0);
667
668 taddr6 = nd_na->nd_na_target;
669 if (in6_setscope(&taddr6, ifp, NULL))
670 goto bad; /* XXX: impossible */
671
672 if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
673 nd6log((LOG_ERR,
674 "nd6_na_input: invalid target address %s\n",
675 ip6_sprintf(ip6bufs, &taddr6)));
676 goto bad;
677 }
678 if (IN6_IS_ADDR_MULTICAST(&daddr6))
679 if (is_solicited) {
680 nd6log((LOG_ERR,
681 "nd6_na_input: a solicited adv is multicasted\n"));
682 goto bad;
683 }
684
685 icmp6len -= sizeof(*nd_na);
686 nd6_option_init(nd_na + 1, icmp6len, &ndopts);
687 if (nd6_options(&ndopts) < 0) {
688 nd6log((LOG_INFO,
689 "nd6_na_input: invalid ND option, ignored\n"));
690 /* nd6_options have incremented stats */
691 goto freeit;
692 }
693
694 if (ndopts.nd_opts_tgt_lladdr) {
695 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
696 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
697 }
698
699 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6);
700
701 /*
702 * Target address matches one of my interface address.
703 *
704 * If my address is tentative, this means that there's somebody
705 * already using the same address as mine. This indicates DAD failure.
706 * This is defined in RFC 2462.
707 *
708 * Otherwise, process as defined in RFC 2461.
709 */
710 if (ifa
711 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) {
712 ifa_free(ifa);
713 nd6_dad_na_input(ifa);
714 goto freeit;
715 }
716
717 /* Just for safety, maybe unnecessary. */
718 if (ifa) {
719 ifa_free(ifa);
720 log(LOG_ERR,
721 "nd6_na_input: duplicate IP6 address %s\n",
722 ip6_sprintf(ip6bufs, &taddr6));
723 goto freeit;
724 }
725
726 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
727 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s "
728 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6),
729 ifp->if_addrlen, lladdrlen - 2));
730 goto bad;
731 }
732
733 /*
734 * If no neighbor cache entry is found, NA SHOULD silently be
735 * discarded.
736 */
737 IF_AFDATA_LOCK(ifp);
738 ln = nd6_lookup(&taddr6, LLE_EXCLUSIVE, ifp);
739 IF_AFDATA_UNLOCK(ifp);
740 if (ln == NULL) {
741 goto freeit;
742 }
743
744 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
745 /*
746 * If the link-layer has address, and no lladdr option came,
747 * discard the packet.
748 */
749 if (ifp->if_addrlen && lladdr == NULL) {
750 goto freeit;
751 }
752
753 /*
754 * Record link-layer address, and update the state.
755 */
756 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen);
757 ln->la_flags |= LLE_VALID;
758 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED);
759 if (is_solicited) {
760 ln->ln_state = ND6_LLINFO_REACHABLE;
761 ln->ln_byhint = 0;
762 if (!ND6_LLINFO_PERMANENT(ln)) {
763 nd6_llinfo_settimer_locked(ln,
764 (long)ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz);
765 }
766 } else {
767 ln->ln_state = ND6_LLINFO_STALE;
768 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz);
769 }
770 if ((ln->ln_router = is_router) != 0) {
771 /*
772 * This means a router's state has changed from
773 * non-reachable to probably reachable, and might
774 * affect the status of associated prefixes..
775 */
776 checklink = 1;
777 }
778 } else {
779 int llchange;
780
781 /*
782 * Check if the link-layer address has changed or not.
783 */
784 if (lladdr == NULL)
785 llchange = 0;
786 else {
787 if (ln->la_flags & LLE_VALID) {
788 if (bcmp(lladdr, &ln->ll_addr, ifp->if_addrlen))
789 llchange = 1;
790 else
791 llchange = 0;
792 } else
793 llchange = 1;
794 }
795
796 /*
797 * This is VERY complex. Look at it with care.
798 *
799 * override solicit lladdr llchange action
800 * (L: record lladdr)
801 *
802 * 0 0 n -- (2c)
803 * 0 0 y n (2b) L
804 * 0 0 y y (1) REACHABLE->STALE
805 * 0 1 n -- (2c) *->REACHABLE
806 * 0 1 y n (2b) L *->REACHABLE
807 * 0 1 y y (1) REACHABLE->STALE
808 * 1 0 n -- (2a)
809 * 1 0 y n (2a) L
810 * 1 0 y y (2a) L *->STALE
811 * 1 1 n -- (2a) *->REACHABLE
812 * 1 1 y n (2a) L *->REACHABLE
813 * 1 1 y y (2a) L *->REACHABLE
814 */
815 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */
816 /*
817 * If state is REACHABLE, make it STALE.
818 * no other updates should be done.
819 */
820 if (ln->ln_state == ND6_LLINFO_REACHABLE) {
821 ln->ln_state = ND6_LLINFO_STALE;
822 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz);
823 }
824 goto freeit;
825 } else if (is_override /* (2a) */
826 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */
827 || lladdr == NULL) { /* (2c) */
828 /*
829 * Update link-local address, if any.
830 */
831 if (lladdr != NULL) {
832 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen);
833 ln->la_flags |= LLE_VALID;
834 EVENTHANDLER_INVOKE(lle_event, ln,
835 LLENTRY_RESOLVED);
836 }
837
838 /*
839 * If solicited, make the state REACHABLE.
840 * If not solicited and the link-layer address was
841 * changed, make it STALE.
842 */
843 if (is_solicited) {
844 ln->ln_state = ND6_LLINFO_REACHABLE;
845 ln->ln_byhint = 0;
846 if (!ND6_LLINFO_PERMANENT(ln)) {
847 nd6_llinfo_settimer_locked(ln,
848 (long)ND_IFINFO(ifp)->reachable * hz);
849 }
850 } else {
851 if (lladdr != NULL && llchange) {
852 ln->ln_state = ND6_LLINFO_STALE;
853 nd6_llinfo_settimer_locked(ln,
854 (long)V_nd6_gctimer * hz);
855 }
856 }
857 }
858
859 if (ln->ln_router && !is_router) {
860 /*
861 * The peer dropped the router flag.
862 * Remove the sender from the Default Router List and
863 * update the Destination Cache entries.
864 */
865 struct nd_defrouter *dr;
866 struct in6_addr *in6;
867
868 in6 = &L3_ADDR_SIN6(ln)->sin6_addr;
869
870 /*
871 * Lock to protect the default router list.
872 * XXX: this might be unnecessary, since this function
873 * is only called under the network software interrupt
874 * context. However, we keep it just for safety.
875 */
876 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp);
877 if (dr)
878 defrtrlist_del(dr);
879 else if (ND_IFINFO(ln->lle_tbl->llt_ifp)->flags &
880 ND6_IFF_ACCEPT_RTADV) {
881 /*
882 * Even if the neighbor is not in the default
883 * router list, the neighbor may be used
884 * as a next hop for some destinations
885 * (e.g. redirect case). So we must
886 * call rt6_flush explicitly.
887 */
888 rt6_flush(&ip6->ip6_src, ifp);
889 }
890 }
891 ln->ln_router = is_router;
892 }
893 /* XXX - QL
894 * Does this matter?
895 * rt->rt_flags &= ~RTF_REJECT;
896 */
897 ln->la_asked = 0;
898 if (ln->la_hold) {
899 struct mbuf *m_hold, *m_hold_next;
900
901 /*
902 * reset the la_hold in advance, to explicitly
903 * prevent a la_hold lookup in nd6_output()
904 * (wouldn't happen, though...)
905 */
906 for (m_hold = ln->la_hold, ln->la_hold = NULL;
907 m_hold; m_hold = m_hold_next) {
908 m_hold_next = m_hold->m_nextpkt;
909 m_hold->m_nextpkt = NULL;
910 /*
911 * we assume ifp is not a loopback here, so just set
912 * the 2nd argument as the 1st one.
913 */
914
915 if (send_sendso_input_hook != NULL) {
916 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING,
917 sizeof(unsigned short), M_NOWAIT);
918 if (mtag == NULL)
919 goto bad;
920 m_tag_prepend(m, mtag);
921 }
922
923 nd6_output_lle(ifp, ifp, m_hold, L3_ADDR_SIN6(ln), NULL, ln, &chain);
924 }
925 }
926 freeit:
927 if (ln != NULL) {
928 if (chain)
929 memcpy(&sin6, L3_ADDR_SIN6(ln), sizeof(sin6));
930 LLE_WUNLOCK(ln);
931
932 if (chain)
933 nd6_output_flush(ifp, ifp, chain, &sin6, NULL);
934 }
935 if (checklink)
936 pfxlist_onlink_check();
937
938 m_freem(m);
939 return;
940
941 bad:
942 if (ln != NULL)
943 LLE_WUNLOCK(ln);
944
945 ICMP6STAT_INC(icp6s_badna);
946 m_freem(m);
947 }
948
949 /*
950 * Neighbor advertisement output handling.
951 *
952 * Based on RFC 2461
953 *
954 * the following items are not implemented yet:
955 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
956 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
957 *
958 * tlladdr - 1 if include target link-layer address
959 * sdl0 - sockaddr_dl (= proxy NA) or NULL
960 */
961 static void
962 nd6_na_output_fib(struct ifnet *ifp, const struct in6_addr *daddr6_0,
963 const struct in6_addr *taddr6, u_long flags, int tlladdr,
964 struct sockaddr *sdl0, u_int fibnum)
965 {
966 struct mbuf *m;
967 struct m_tag *mtag;
968 struct ifnet *oifp;
969 struct ip6_hdr *ip6;
970 struct nd_neighbor_advert *nd_na;
971 struct ip6_moptions im6o;
972 struct in6_addr src, daddr6;
973 struct sockaddr_in6 dst_sa;
974 int icmp6len, maxlen, error;
975 caddr_t mac = NULL;
976 struct route_in6 ro;
977
978 bzero(&ro, sizeof(ro));
979
980 daddr6 = *daddr6_0; /* make a local copy for modification */
981
982 /* estimate the size of message */
983 maxlen = sizeof(*ip6) + sizeof(*nd_na);
984 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
985 if (max_linkhdr + maxlen >= MCLBYTES) {
986 #ifdef DIAGNOSTIC
987 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES "
988 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
989 #endif
990 return;
991 }
992
993 MGETHDR(m, M_DONTWAIT, MT_DATA);
994 if (m && max_linkhdr + maxlen >= MHLEN) {
995 MCLGET(m, M_DONTWAIT);
996 if ((m->m_flags & M_EXT) == 0) {
997 m_free(m);
998 m = NULL;
999 }
1000 }
1001 if (m == NULL)
1002 return;
1003 m->m_pkthdr.rcvif = NULL;
1004 M_SETFIB(m, fibnum);
1005
1006 if (IN6_IS_ADDR_MULTICAST(&daddr6)) {
1007 m->m_flags |= M_MCAST;
1008 im6o.im6o_multicast_ifp = ifp;
1009 im6o.im6o_multicast_hlim = 255;
1010 im6o.im6o_multicast_loop = 0;
1011 }
1012
1013 icmp6len = sizeof(*nd_na);
1014 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len;
1015 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
1016
1017 /* fill neighbor advertisement packet */
1018 ip6 = mtod(m, struct ip6_hdr *);
1019 ip6->ip6_flow = 0;
1020 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
1021 ip6->ip6_vfc |= IPV6_VERSION;
1022 ip6->ip6_nxt = IPPROTO_ICMPV6;
1023 ip6->ip6_hlim = 255;
1024 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) {
1025 /* reply to DAD */
1026 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
1027 daddr6.s6_addr16[1] = 0;
1028 daddr6.s6_addr32[1] = 0;
1029 daddr6.s6_addr32[2] = 0;
1030 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE;
1031 if (in6_setscope(&daddr6, ifp, NULL))
1032 goto bad;
1033
1034 flags &= ~ND_NA_FLAG_SOLICITED;
1035 }
1036 ip6->ip6_dst = daddr6;
1037 bzero(&dst_sa, sizeof(struct sockaddr_in6));
1038 dst_sa.sin6_family = AF_INET6;
1039 dst_sa.sin6_len = sizeof(struct sockaddr_in6);
1040 dst_sa.sin6_addr = daddr6;
1041
1042 /*
1043 * Select a source whose scope is the same as that of the dest.
1044 */
1045 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa));
1046 oifp = ifp;
1047 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &oifp, &src);
1048 if (error) {
1049 char ip6buf[INET6_ADDRSTRLEN];
1050 nd6log((LOG_DEBUG, "nd6_na_output: source can't be "
1051 "determined: dst=%s, error=%d\n",
1052 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error));
1053 goto bad;
1054 }
1055 ip6->ip6_src = src;
1056 nd_na = (struct nd_neighbor_advert *)(ip6 + 1);
1057 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT;
1058 nd_na->nd_na_code = 0;
1059 nd_na->nd_na_target = *taddr6;
1060 in6_clearscope(&nd_na->nd_na_target); /* XXX */
1061
1062 /*
1063 * "tlladdr" indicates NS's condition for adding tlladdr or not.
1064 * see nd6_ns_input() for details.
1065 * Basically, if NS packet is sent to unicast/anycast addr,
1066 * target lladdr option SHOULD NOT be included.
1067 */
1068 if (tlladdr) {
1069 /*
1070 * sdl0 != NULL indicates proxy NA. If we do proxy, use
1071 * lladdr in sdl0. If we are not proxying (sending NA for
1072 * my address) use lladdr configured for the interface.
1073 */
1074 if (sdl0 == NULL) {
1075 if (ifp->if_carp)
1076 mac = (*carp_macmatch6_p)(ifp, m, taddr6);
1077 if (mac == NULL)
1078 mac = nd6_ifptomac(ifp);
1079 } else if (sdl0->sa_family == AF_LINK) {
1080 struct sockaddr_dl *sdl;
1081 sdl = (struct sockaddr_dl *)sdl0;
1082 if (sdl->sdl_alen == ifp->if_addrlen)
1083 mac = LLADDR(sdl);
1084 }
1085 }
1086 if (tlladdr && mac) {
1087 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
1088 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1);
1089
1090 /* roundup to 8 bytes alignment! */
1091 optlen = (optlen + 7) & ~7;
1092
1093 m->m_pkthdr.len += optlen;
1094 m->m_len += optlen;
1095 icmp6len += optlen;
1096 bzero((caddr_t)nd_opt, optlen);
1097 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
1098 nd_opt->nd_opt_len = optlen >> 3;
1099 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
1100 } else
1101 flags &= ~ND_NA_FLAG_OVERRIDE;
1102
1103 ip6->ip6_plen = htons((u_short)icmp6len);
1104 nd_na->nd_na_flags_reserved = flags;
1105 nd_na->nd_na_cksum = 0;
1106 nd_na->nd_na_cksum =
1107 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len);
1108
1109 if (send_sendso_input_hook != NULL) {
1110 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING,
1111 sizeof(unsigned short), M_NOWAIT);
1112 if (mtag == NULL)
1113 goto bad;
1114 *(unsigned short *)(mtag + 1) = nd_na->nd_na_type;
1115 m_tag_prepend(m, mtag);
1116 }
1117
1118 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL);
1119 icmp6_ifstat_inc(ifp, ifs6_out_msg);
1120 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert);
1121 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]);
1122
1123 /* We don't cache this route. */
1124 RO_RTFREE(&ro);
1125
1126 return;
1127
1128 bad:
1129 if (ro.ro_rt) {
1130 RTFREE(ro.ro_rt);
1131 }
1132 m_freem(m);
1133 return;
1134 }
1135
1136 #ifndef BURN_BRIDGES
1137 void
1138 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0,
1139 const struct in6_addr *taddr6, u_long flags, int tlladdr,
1140 struct sockaddr *sdl0)
1141 {
1142
1143 nd6_na_output_fib(ifp, daddr6_0, taddr6, flags, tlladdr, sdl0,
1144 RT_DEFAULT_FIB);
1145 }
1146 #endif
1147
1148 caddr_t
1149 nd6_ifptomac(struct ifnet *ifp)
1150 {
1151 switch (ifp->if_type) {
1152 case IFT_ARCNET:
1153 case IFT_ETHER:
1154 case IFT_FDDI:
1155 case IFT_IEEE1394:
1156 #ifdef IFT_L2VLAN
1157 case IFT_L2VLAN:
1158 #endif
1159 #ifdef IFT_IEEE80211
1160 case IFT_IEEE80211:
1161 #endif
1162 #ifdef IFT_CARP
1163 case IFT_CARP:
1164 #endif
1165 case IFT_INFINIBAND:
1166 case IFT_BRIDGE:
1167 case IFT_ISO88025:
1168 return IF_LLADDR(ifp);
1169 default:
1170 return NULL;
1171 }
1172 }
1173
1174 struct dadq {
1175 TAILQ_ENTRY(dadq) dad_list;
1176 struct ifaddr *dad_ifa;
1177 int dad_count; /* max NS to send */
1178 int dad_ns_tcount; /* # of trials to send NS */
1179 int dad_ns_ocount; /* NS sent so far */
1180 int dad_ns_icount;
1181 int dad_na_icount;
1182 struct callout dad_timer_ch;
1183 struct vnet *dad_vnet;
1184 };
1185
1186 static VNET_DEFINE(TAILQ_HEAD(, dadq), dadq);
1187 VNET_DEFINE(int, dad_init) = 0;
1188 #define V_dadq VNET(dadq)
1189 #define V_dad_init VNET(dad_init)
1190
1191 static struct dadq *
1192 nd6_dad_find(struct ifaddr *ifa)
1193 {
1194 struct dadq *dp;
1195
1196 TAILQ_FOREACH(dp, &V_dadq, dad_list)
1197 if (dp->dad_ifa == ifa)
1198 return (dp);
1199
1200 return (NULL);
1201 }
1202
1203 static void
1204 nd6_dad_starttimer(struct dadq *dp, int ticks)
1205 {
1206
1207 callout_reset(&dp->dad_timer_ch, ticks,
1208 (void (*)(void *))nd6_dad_timer, (void *)dp);
1209 }
1210
1211 static void
1212 nd6_dad_stoptimer(struct dadq *dp)
1213 {
1214
1215 callout_stop(&dp->dad_timer_ch);
1216 }
1217
1218 /*
1219 * Start Duplicate Address Detection (DAD) for specified interface address.
1220 */
1221 void
1222 nd6_dad_start(struct ifaddr *ifa, int delay)
1223 {
1224 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1225 struct dadq *dp;
1226 char ip6buf[INET6_ADDRSTRLEN];
1227
1228 if (!V_dad_init) {
1229 TAILQ_INIT(&V_dadq);
1230 V_dad_init++;
1231 }
1232
1233 /*
1234 * If we don't need DAD, don't do it.
1235 * There are several cases:
1236 * - DAD is disabled (ip6_dad_count == 0)
1237 * - the interface address is anycast
1238 */
1239 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
1240 log(LOG_DEBUG,
1241 "nd6_dad_start: called with non-tentative address "
1242 "%s(%s)\n",
1243 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1244 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1245 return;
1246 }
1247 if (ia->ia6_flags & IN6_IFF_ANYCAST) {
1248 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1249 return;
1250 }
1251 if (!V_ip6_dad_count) {
1252 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1253 return;
1254 }
1255 if (ifa->ifa_ifp == NULL)
1256 panic("nd6_dad_start: ifa->ifa_ifp == NULL");
1257 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) {
1258 return;
1259 }
1260 if (ND_IFINFO(ifa->ifa_ifp)->flags & ND6_IFF_IFDISABLED)
1261 return;
1262 if (nd6_dad_find(ifa) != NULL) {
1263 /* DAD already in progress */
1264 return;
1265 }
1266
1267 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT);
1268 if (dp == NULL) {
1269 log(LOG_ERR, "nd6_dad_start: memory allocation failed for "
1270 "%s(%s)\n",
1271 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1272 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1273 return;
1274 }
1275 bzero(dp, sizeof(*dp));
1276 callout_init(&dp->dad_timer_ch, 0);
1277 #ifdef VIMAGE
1278 dp->dad_vnet = curvnet;
1279 #endif
1280 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list);
1281
1282 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp),
1283 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1284
1285 /*
1286 * Send NS packet for DAD, ip6_dad_count times.
1287 * Note that we must delay the first transmission, if this is the
1288 * first packet to be sent from the interface after interface
1289 * (re)initialization.
1290 */
1291 dp->dad_ifa = ifa;
1292 ifa_ref(ifa); /* just for safety */
1293 dp->dad_count = V_ip6_dad_count;
1294 dp->dad_ns_icount = dp->dad_na_icount = 0;
1295 dp->dad_ns_ocount = dp->dad_ns_tcount = 0;
1296 if (delay == 0) {
1297 nd6_dad_ns_output(dp, ifa);
1298 nd6_dad_starttimer(dp,
1299 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1300 } else {
1301 nd6_dad_starttimer(dp, delay);
1302 }
1303 }
1304
1305 /*
1306 * terminate DAD unconditionally. used for address removals.
1307 */
1308 void
1309 nd6_dad_stop(struct ifaddr *ifa)
1310 {
1311 struct dadq *dp;
1312
1313 if (!V_dad_init)
1314 return;
1315 dp = nd6_dad_find(ifa);
1316 if (!dp) {
1317 /* DAD wasn't started yet */
1318 return;
1319 }
1320
1321 nd6_dad_stoptimer(dp);
1322
1323 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list);
1324 free(dp, M_IP6NDP);
1325 dp = NULL;
1326 ifa_free(ifa);
1327 }
1328
1329 static void
1330 nd6_dad_timer(struct dadq *dp)
1331 {
1332 CURVNET_SET(dp->dad_vnet);
1333 int s;
1334 struct ifaddr *ifa = dp->dad_ifa;
1335 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1336 char ip6buf[INET6_ADDRSTRLEN];
1337
1338 s = splnet(); /* XXX */
1339
1340 /* Sanity check */
1341 if (ia == NULL) {
1342 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n");
1343 goto done;
1344 }
1345 if (ia->ia6_flags & IN6_IFF_DUPLICATED) {
1346 log(LOG_ERR, "nd6_dad_timer: called with duplicated address "
1347 "%s(%s)\n",
1348 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1349 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1350 goto done;
1351 }
1352 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) {
1353 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address "
1354 "%s(%s)\n",
1355 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1356 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1357 goto done;
1358 }
1359
1360 /* timeouted with IFF_{RUNNING,UP} check */
1361 if (dp->dad_ns_tcount > V_dad_maxtry) {
1362 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n",
1363 if_name(ifa->ifa_ifp)));
1364
1365 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list);
1366 free(dp, M_IP6NDP);
1367 dp = NULL;
1368 ifa_free(ifa);
1369 goto done;
1370 }
1371
1372 /* Need more checks? */
1373 if (dp->dad_ns_ocount < dp->dad_count) {
1374 /*
1375 * We have more NS to go. Send NS packet for DAD.
1376 */
1377 nd6_dad_ns_output(dp, ifa);
1378 nd6_dad_starttimer(dp,
1379 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1380 } else {
1381 /*
1382 * We have transmitted sufficient number of DAD packets.
1383 * See what we've got.
1384 */
1385 int duplicate;
1386
1387 duplicate = 0;
1388
1389 if (dp->dad_na_icount) {
1390 /*
1391 * the check is in nd6_dad_na_input(),
1392 * but just in case
1393 */
1394 duplicate++;
1395 }
1396
1397 if (dp->dad_ns_icount) {
1398 /* We've seen NS, means DAD has failed. */
1399 duplicate++;
1400 }
1401
1402 if (duplicate) {
1403 /* (*dp) will be freed in nd6_dad_duplicated() */
1404 dp = NULL;
1405 nd6_dad_duplicated(ifa);
1406 } else {
1407 /*
1408 * We are done with DAD. No NA came, no NS came.
1409 * No duplicate address found.
1410 */
1411 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1412
1413 nd6log((LOG_DEBUG,
1414 "%s: DAD complete for %s - no duplicates found\n",
1415 if_name(ifa->ifa_ifp),
1416 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1417
1418 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list);
1419 free(dp, M_IP6NDP);
1420 dp = NULL;
1421 ifa_free(ifa);
1422 }
1423 }
1424
1425 done:
1426 splx(s);
1427 CURVNET_RESTORE();
1428 }
1429
1430 void
1431 nd6_dad_duplicated(struct ifaddr *ifa)
1432 {
1433 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1434 struct ifnet *ifp;
1435 struct dadq *dp;
1436 char ip6buf[INET6_ADDRSTRLEN];
1437
1438 dp = nd6_dad_find(ifa);
1439 if (dp == NULL) {
1440 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n");
1441 return;
1442 }
1443
1444 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: "
1445 "NS in/out=%d/%d, NA in=%d\n",
1446 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1447 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount);
1448
1449 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1450 ia->ia6_flags |= IN6_IFF_DUPLICATED;
1451
1452 /* We are done with DAD, with duplicate address found. (failure) */
1453 nd6_dad_stoptimer(dp);
1454
1455 ifp = ifa->ifa_ifp;
1456 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n",
1457 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr));
1458 log(LOG_ERR, "%s: manual intervention required\n",
1459 if_name(ifp));
1460
1461 /*
1462 * If the address is a link-local address formed from an interface
1463 * identifier based on the hardware address which is supposed to be
1464 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP
1465 * operation on the interface SHOULD be disabled.
1466 * [RFC 4862, Section 5.4.5]
1467 */
1468 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) {
1469 struct in6_addr in6;
1470
1471 /*
1472 * To avoid over-reaction, we only apply this logic when we are
1473 * very sure that hardware addresses are supposed to be unique.
1474 */
1475 switch (ifp->if_type) {
1476 case IFT_ETHER:
1477 case IFT_FDDI:
1478 case IFT_ATM:
1479 case IFT_IEEE1394:
1480 #ifdef IFT_IEEE80211
1481 case IFT_IEEE80211:
1482 #endif
1483 case IFT_INFINIBAND:
1484 in6 = ia->ia_addr.sin6_addr;
1485 if (in6_get_hw_ifid(ifp, &in6) == 0 &&
1486 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) {
1487 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED;
1488 log(LOG_ERR, "%s: possible hardware address "
1489 "duplication detected, disable IPv6\n",
1490 if_name(ifp));
1491 }
1492 break;
1493 }
1494 }
1495
1496 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list);
1497 free(dp, M_IP6NDP);
1498 dp = NULL;
1499 ifa_free(ifa);
1500 }
1501
1502 static void
1503 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa)
1504 {
1505 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1506 struct ifnet *ifp = ifa->ifa_ifp;
1507
1508 dp->dad_ns_tcount++;
1509 if ((ifp->if_flags & IFF_UP) == 0) {
1510 return;
1511 }
1512 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
1513 return;
1514 }
1515
1516 dp->dad_ns_ocount++;
1517 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1);
1518 }
1519
1520 static void
1521 nd6_dad_ns_input(struct ifaddr *ifa)
1522 {
1523 struct in6_ifaddr *ia;
1524 struct ifnet *ifp;
1525 const struct in6_addr *taddr6;
1526 struct dadq *dp;
1527 int duplicate;
1528
1529 if (ifa == NULL)
1530 panic("ifa == NULL in nd6_dad_ns_input");
1531
1532 ia = (struct in6_ifaddr *)ifa;
1533 ifp = ifa->ifa_ifp;
1534 taddr6 = &ia->ia_addr.sin6_addr;
1535 duplicate = 0;
1536 dp = nd6_dad_find(ifa);
1537
1538 /* Quickhack - completely ignore DAD NS packets */
1539 if (V_dad_ignore_ns) {
1540 char ip6buf[INET6_ADDRSTRLEN];
1541 nd6log((LOG_INFO,
1542 "nd6_dad_ns_input: ignoring DAD NS packet for "
1543 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6),
1544 if_name(ifa->ifa_ifp)));
1545 return;
1546 }
1547
1548 /*
1549 * if I'm yet to start DAD, someone else started using this address
1550 * first. I have a duplicate and you win.
1551 */
1552 if (dp == NULL || dp->dad_ns_ocount == 0)
1553 duplicate++;
1554
1555 /* XXX more checks for loopback situation - see nd6_dad_timer too */
1556
1557 if (duplicate) {
1558 dp = NULL; /* will be freed in nd6_dad_duplicated() */
1559 nd6_dad_duplicated(ifa);
1560 } else {
1561 /*
1562 * not sure if I got a duplicate.
1563 * increment ns count and see what happens.
1564 */
1565 if (dp)
1566 dp->dad_ns_icount++;
1567 }
1568 }
1569
1570 static void
1571 nd6_dad_na_input(struct ifaddr *ifa)
1572 {
1573 struct dadq *dp;
1574
1575 if (ifa == NULL)
1576 panic("ifa == NULL in nd6_dad_na_input");
1577
1578 dp = nd6_dad_find(ifa);
1579 if (dp)
1580 dp->dad_na_icount++;
1581
1582 /* remove the address. */
1583 nd6_dad_duplicated(ifa);
1584 }
Cache object: 8990a1b66d740f768cf3a3fbe351229a
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