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/9.1/sys/netinet6/nd6_nbr.c 233046 2012-03-16 21:28:05Z jhb $");
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 if (ro.ro_rt) { /* we don't cache this route. */
599 RTFREE(ro.ro_rt);
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 if (is_solicited) {
759 ln->ln_state = ND6_LLINFO_REACHABLE;
760 ln->ln_byhint = 0;
761 if (!ND6_LLINFO_PERMANENT(ln)) {
762 nd6_llinfo_settimer_locked(ln,
763 (long)ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz);
764 }
765 } else {
766 ln->ln_state = ND6_LLINFO_STALE;
767 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz);
768 }
769 if ((ln->ln_router = is_router) != 0) {
770 /*
771 * This means a router's state has changed from
772 * non-reachable to probably reachable, and might
773 * affect the status of associated prefixes..
774 */
775 checklink = 1;
776 }
777 } else {
778 int llchange;
779
780 /*
781 * Check if the link-layer address has changed or not.
782 */
783 if (lladdr == NULL)
784 llchange = 0;
785 else {
786 if (ln->la_flags & LLE_VALID) {
787 if (bcmp(lladdr, &ln->ll_addr, ifp->if_addrlen))
788 llchange = 1;
789 else
790 llchange = 0;
791 } else
792 llchange = 1;
793 }
794
795 /*
796 * This is VERY complex. Look at it with care.
797 *
798 * override solicit lladdr llchange action
799 * (L: record lladdr)
800 *
801 * 0 0 n -- (2c)
802 * 0 0 y n (2b) L
803 * 0 0 y y (1) REACHABLE->STALE
804 * 0 1 n -- (2c) *->REACHABLE
805 * 0 1 y n (2b) L *->REACHABLE
806 * 0 1 y y (1) REACHABLE->STALE
807 * 1 0 n -- (2a)
808 * 1 0 y n (2a) L
809 * 1 0 y y (2a) L *->STALE
810 * 1 1 n -- (2a) *->REACHABLE
811 * 1 1 y n (2a) L *->REACHABLE
812 * 1 1 y y (2a) L *->REACHABLE
813 */
814 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */
815 /*
816 * If state is REACHABLE, make it STALE.
817 * no other updates should be done.
818 */
819 if (ln->ln_state == ND6_LLINFO_REACHABLE) {
820 ln->ln_state = ND6_LLINFO_STALE;
821 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz);
822 }
823 goto freeit;
824 } else if (is_override /* (2a) */
825 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */
826 || lladdr == NULL) { /* (2c) */
827 /*
828 * Update link-local address, if any.
829 */
830 if (lladdr != NULL) {
831 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen);
832 ln->la_flags |= LLE_VALID;
833 }
834
835 /*
836 * If solicited, make the state REACHABLE.
837 * If not solicited and the link-layer address was
838 * changed, make it STALE.
839 */
840 if (is_solicited) {
841 ln->ln_state = ND6_LLINFO_REACHABLE;
842 ln->ln_byhint = 0;
843 if (!ND6_LLINFO_PERMANENT(ln)) {
844 nd6_llinfo_settimer_locked(ln,
845 (long)ND_IFINFO(ifp)->reachable * hz);
846 }
847 } else {
848 if (lladdr != NULL && llchange) {
849 ln->ln_state = ND6_LLINFO_STALE;
850 nd6_llinfo_settimer_locked(ln,
851 (long)V_nd6_gctimer * hz);
852 }
853 }
854 }
855
856 if (ln->ln_router && !is_router) {
857 /*
858 * The peer dropped the router flag.
859 * Remove the sender from the Default Router List and
860 * update the Destination Cache entries.
861 */
862 struct nd_defrouter *dr;
863 struct in6_addr *in6;
864
865 in6 = &L3_ADDR_SIN6(ln)->sin6_addr;
866
867 /*
868 * Lock to protect the default router list.
869 * XXX: this might be unnecessary, since this function
870 * is only called under the network software interrupt
871 * context. However, we keep it just for safety.
872 */
873 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp);
874 if (dr)
875 defrtrlist_del(dr);
876 else if (ND_IFINFO(ln->lle_tbl->llt_ifp)->flags &
877 ND6_IFF_ACCEPT_RTADV) {
878 /*
879 * Even if the neighbor is not in the default
880 * router list, the neighbor may be used
881 * as a next hop for some destinations
882 * (e.g. redirect case). So we must
883 * call rt6_flush explicitly.
884 */
885 rt6_flush(&ip6->ip6_src, ifp);
886 }
887 }
888 ln->ln_router = is_router;
889 }
890 /* XXX - QL
891 * Does this matter?
892 * rt->rt_flags &= ~RTF_REJECT;
893 */
894 ln->la_asked = 0;
895 if (ln->la_hold) {
896 struct mbuf *m_hold, *m_hold_next;
897
898 /*
899 * reset the la_hold in advance, to explicitly
900 * prevent a la_hold lookup in nd6_output()
901 * (wouldn't happen, though...)
902 */
903 for (m_hold = ln->la_hold, ln->la_hold = NULL;
904 m_hold; m_hold = m_hold_next) {
905 m_hold_next = m_hold->m_nextpkt;
906 m_hold->m_nextpkt = NULL;
907 /*
908 * we assume ifp is not a loopback here, so just set
909 * the 2nd argument as the 1st one.
910 */
911
912 if (send_sendso_input_hook != NULL) {
913 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING,
914 sizeof(unsigned short), M_NOWAIT);
915 if (mtag == NULL)
916 goto bad;
917 m_tag_prepend(m, mtag);
918 }
919
920 nd6_output_lle(ifp, ifp, m_hold, L3_ADDR_SIN6(ln), NULL, ln, &chain);
921 }
922 }
923 freeit:
924 if (ln != NULL) {
925 if (chain)
926 memcpy(&sin6, L3_ADDR_SIN6(ln), sizeof(sin6));
927 LLE_WUNLOCK(ln);
928
929 if (chain)
930 nd6_output_flush(ifp, ifp, chain, &sin6, NULL);
931 }
932 if (checklink)
933 pfxlist_onlink_check();
934
935 m_freem(m);
936 return;
937
938 bad:
939 if (ln != NULL)
940 LLE_WUNLOCK(ln);
941
942 ICMP6STAT_INC(icp6s_badna);
943 m_freem(m);
944 }
945
946 /*
947 * Neighbor advertisement output handling.
948 *
949 * Based on RFC 2461
950 *
951 * the following items are not implemented yet:
952 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
953 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
954 *
955 * tlladdr - 1 if include target link-layer address
956 * sdl0 - sockaddr_dl (= proxy NA) or NULL
957 */
958 static void
959 nd6_na_output_fib(struct ifnet *ifp, const struct in6_addr *daddr6_0,
960 const struct in6_addr *taddr6, u_long flags, int tlladdr,
961 struct sockaddr *sdl0, u_int fibnum)
962 {
963 struct mbuf *m;
964 struct m_tag *mtag;
965 struct ifnet *oifp;
966 struct ip6_hdr *ip6;
967 struct nd_neighbor_advert *nd_na;
968 struct ip6_moptions im6o;
969 struct in6_addr src, daddr6;
970 struct sockaddr_in6 dst_sa;
971 int icmp6len, maxlen, error;
972 caddr_t mac = NULL;
973 struct route_in6 ro;
974
975 bzero(&ro, sizeof(ro));
976
977 daddr6 = *daddr6_0; /* make a local copy for modification */
978
979 /* estimate the size of message */
980 maxlen = sizeof(*ip6) + sizeof(*nd_na);
981 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
982 if (max_linkhdr + maxlen >= MCLBYTES) {
983 #ifdef DIAGNOSTIC
984 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES "
985 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES);
986 #endif
987 return;
988 }
989
990 MGETHDR(m, M_DONTWAIT, MT_DATA);
991 if (m && max_linkhdr + maxlen >= MHLEN) {
992 MCLGET(m, M_DONTWAIT);
993 if ((m->m_flags & M_EXT) == 0) {
994 m_free(m);
995 m = NULL;
996 }
997 }
998 if (m == NULL)
999 return;
1000 m->m_pkthdr.rcvif = NULL;
1001 M_SETFIB(m, fibnum);
1002
1003 if (IN6_IS_ADDR_MULTICAST(&daddr6)) {
1004 m->m_flags |= M_MCAST;
1005 im6o.im6o_multicast_ifp = ifp;
1006 im6o.im6o_multicast_hlim = 255;
1007 im6o.im6o_multicast_loop = 0;
1008 }
1009
1010 icmp6len = sizeof(*nd_na);
1011 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len;
1012 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */
1013
1014 /* fill neighbor advertisement packet */
1015 ip6 = mtod(m, struct ip6_hdr *);
1016 ip6->ip6_flow = 0;
1017 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
1018 ip6->ip6_vfc |= IPV6_VERSION;
1019 ip6->ip6_nxt = IPPROTO_ICMPV6;
1020 ip6->ip6_hlim = 255;
1021 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) {
1022 /* reply to DAD */
1023 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
1024 daddr6.s6_addr16[1] = 0;
1025 daddr6.s6_addr32[1] = 0;
1026 daddr6.s6_addr32[2] = 0;
1027 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE;
1028 if (in6_setscope(&daddr6, ifp, NULL))
1029 goto bad;
1030
1031 flags &= ~ND_NA_FLAG_SOLICITED;
1032 }
1033 ip6->ip6_dst = daddr6;
1034 bzero(&dst_sa, sizeof(struct sockaddr_in6));
1035 dst_sa.sin6_family = AF_INET6;
1036 dst_sa.sin6_len = sizeof(struct sockaddr_in6);
1037 dst_sa.sin6_addr = daddr6;
1038
1039 /*
1040 * Select a source whose scope is the same as that of the dest.
1041 */
1042 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa));
1043 oifp = ifp;
1044 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &oifp, &src);
1045 if (error) {
1046 char ip6buf[INET6_ADDRSTRLEN];
1047 nd6log((LOG_DEBUG, "nd6_na_output: source can't be "
1048 "determined: dst=%s, error=%d\n",
1049 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error));
1050 goto bad;
1051 }
1052 ip6->ip6_src = src;
1053 nd_na = (struct nd_neighbor_advert *)(ip6 + 1);
1054 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT;
1055 nd_na->nd_na_code = 0;
1056 nd_na->nd_na_target = *taddr6;
1057 in6_clearscope(&nd_na->nd_na_target); /* XXX */
1058
1059 /*
1060 * "tlladdr" indicates NS's condition for adding tlladdr or not.
1061 * see nd6_ns_input() for details.
1062 * Basically, if NS packet is sent to unicast/anycast addr,
1063 * target lladdr option SHOULD NOT be included.
1064 */
1065 if (tlladdr) {
1066 /*
1067 * sdl0 != NULL indicates proxy NA. If we do proxy, use
1068 * lladdr in sdl0. If we are not proxying (sending NA for
1069 * my address) use lladdr configured for the interface.
1070 */
1071 if (sdl0 == NULL) {
1072 if (ifp->if_carp)
1073 mac = (*carp_macmatch6_p)(ifp, m, taddr6);
1074 if (mac == NULL)
1075 mac = nd6_ifptomac(ifp);
1076 } else if (sdl0->sa_family == AF_LINK) {
1077 struct sockaddr_dl *sdl;
1078 sdl = (struct sockaddr_dl *)sdl0;
1079 if (sdl->sdl_alen == ifp->if_addrlen)
1080 mac = LLADDR(sdl);
1081 }
1082 }
1083 if (tlladdr && mac) {
1084 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
1085 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1);
1086
1087 /* roundup to 8 bytes alignment! */
1088 optlen = (optlen + 7) & ~7;
1089
1090 m->m_pkthdr.len += optlen;
1091 m->m_len += optlen;
1092 icmp6len += optlen;
1093 bzero((caddr_t)nd_opt, optlen);
1094 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
1095 nd_opt->nd_opt_len = optlen >> 3;
1096 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen);
1097 } else
1098 flags &= ~ND_NA_FLAG_OVERRIDE;
1099
1100 ip6->ip6_plen = htons((u_short)icmp6len);
1101 nd_na->nd_na_flags_reserved = flags;
1102 nd_na->nd_na_cksum = 0;
1103 nd_na->nd_na_cksum =
1104 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len);
1105
1106 if (send_sendso_input_hook != NULL) {
1107 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING,
1108 sizeof(unsigned short), M_NOWAIT);
1109 if (mtag == NULL)
1110 goto bad;
1111 *(unsigned short *)(mtag + 1) = nd_na->nd_na_type;
1112 m_tag_prepend(m, mtag);
1113 }
1114
1115 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL);
1116 icmp6_ifstat_inc(ifp, ifs6_out_msg);
1117 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert);
1118 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]);
1119
1120 if (ro.ro_rt) { /* we don't cache this route. */
1121 RTFREE(ro.ro_rt);
1122 }
1123 return;
1124
1125 bad:
1126 if (ro.ro_rt) {
1127 RTFREE(ro.ro_rt);
1128 }
1129 m_freem(m);
1130 return;
1131 }
1132
1133 #ifndef BURN_BRIDGES
1134 void
1135 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0,
1136 const struct in6_addr *taddr6, u_long flags, int tlladdr,
1137 struct sockaddr *sdl0)
1138 {
1139
1140 nd6_na_output_fib(ifp, daddr6_0, taddr6, flags, tlladdr, sdl0,
1141 RT_DEFAULT_FIB);
1142 }
1143 #endif
1144
1145 caddr_t
1146 nd6_ifptomac(struct ifnet *ifp)
1147 {
1148 switch (ifp->if_type) {
1149 case IFT_ARCNET:
1150 case IFT_ETHER:
1151 case IFT_FDDI:
1152 case IFT_IEEE1394:
1153 #ifdef IFT_L2VLAN
1154 case IFT_L2VLAN:
1155 #endif
1156 #ifdef IFT_IEEE80211
1157 case IFT_IEEE80211:
1158 #endif
1159 #ifdef IFT_CARP
1160 case IFT_CARP:
1161 #endif
1162 case IFT_INFINIBAND:
1163 case IFT_BRIDGE:
1164 case IFT_ISO88025:
1165 return IF_LLADDR(ifp);
1166 default:
1167 return NULL;
1168 }
1169 }
1170
1171 struct dadq {
1172 TAILQ_ENTRY(dadq) dad_list;
1173 struct ifaddr *dad_ifa;
1174 int dad_count; /* max NS to send */
1175 int dad_ns_tcount; /* # of trials to send NS */
1176 int dad_ns_ocount; /* NS sent so far */
1177 int dad_ns_icount;
1178 int dad_na_icount;
1179 struct callout dad_timer_ch;
1180 struct vnet *dad_vnet;
1181 };
1182
1183 static VNET_DEFINE(TAILQ_HEAD(, dadq), dadq);
1184 VNET_DEFINE(int, dad_init) = 0;
1185 #define V_dadq VNET(dadq)
1186 #define V_dad_init VNET(dad_init)
1187
1188 static struct dadq *
1189 nd6_dad_find(struct ifaddr *ifa)
1190 {
1191 struct dadq *dp;
1192
1193 TAILQ_FOREACH(dp, &V_dadq, dad_list)
1194 if (dp->dad_ifa == ifa)
1195 return (dp);
1196
1197 return (NULL);
1198 }
1199
1200 static void
1201 nd6_dad_starttimer(struct dadq *dp, int ticks)
1202 {
1203
1204 callout_reset(&dp->dad_timer_ch, ticks,
1205 (void (*)(void *))nd6_dad_timer, (void *)dp);
1206 }
1207
1208 static void
1209 nd6_dad_stoptimer(struct dadq *dp)
1210 {
1211
1212 callout_stop(&dp->dad_timer_ch);
1213 }
1214
1215 /*
1216 * Start Duplicate Address Detection (DAD) for specified interface address.
1217 */
1218 void
1219 nd6_dad_start(struct ifaddr *ifa, int delay)
1220 {
1221 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1222 struct dadq *dp;
1223 char ip6buf[INET6_ADDRSTRLEN];
1224
1225 if (!V_dad_init) {
1226 TAILQ_INIT(&V_dadq);
1227 V_dad_init++;
1228 }
1229
1230 /*
1231 * If we don't need DAD, don't do it.
1232 * There are several cases:
1233 * - DAD is disabled (ip6_dad_count == 0)
1234 * - the interface address is anycast
1235 */
1236 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
1237 log(LOG_DEBUG,
1238 "nd6_dad_start: called with non-tentative address "
1239 "%s(%s)\n",
1240 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1241 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1242 return;
1243 }
1244 if (ia->ia6_flags & IN6_IFF_ANYCAST) {
1245 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1246 return;
1247 }
1248 if (!V_ip6_dad_count) {
1249 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1250 return;
1251 }
1252 if (ifa->ifa_ifp == NULL)
1253 panic("nd6_dad_start: ifa->ifa_ifp == NULL");
1254 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) {
1255 return;
1256 }
1257 if (ND_IFINFO(ifa->ifa_ifp)->flags & ND6_IFF_IFDISABLED)
1258 return;
1259 if (nd6_dad_find(ifa) != NULL) {
1260 /* DAD already in progress */
1261 return;
1262 }
1263
1264 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT);
1265 if (dp == NULL) {
1266 log(LOG_ERR, "nd6_dad_start: memory allocation failed for "
1267 "%s(%s)\n",
1268 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1269 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1270 return;
1271 }
1272 bzero(dp, sizeof(*dp));
1273 callout_init(&dp->dad_timer_ch, 0);
1274 #ifdef VIMAGE
1275 dp->dad_vnet = curvnet;
1276 #endif
1277 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list);
1278
1279 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp),
1280 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1281
1282 /*
1283 * Send NS packet for DAD, ip6_dad_count times.
1284 * Note that we must delay the first transmission, if this is the
1285 * first packet to be sent from the interface after interface
1286 * (re)initialization.
1287 */
1288 dp->dad_ifa = ifa;
1289 ifa_ref(ifa); /* just for safety */
1290 dp->dad_count = V_ip6_dad_count;
1291 dp->dad_ns_icount = dp->dad_na_icount = 0;
1292 dp->dad_ns_ocount = dp->dad_ns_tcount = 0;
1293 if (delay == 0) {
1294 nd6_dad_ns_output(dp, ifa);
1295 nd6_dad_starttimer(dp,
1296 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1297 } else {
1298 nd6_dad_starttimer(dp, delay);
1299 }
1300 }
1301
1302 /*
1303 * terminate DAD unconditionally. used for address removals.
1304 */
1305 void
1306 nd6_dad_stop(struct ifaddr *ifa)
1307 {
1308 struct dadq *dp;
1309
1310 if (!V_dad_init)
1311 return;
1312 dp = nd6_dad_find(ifa);
1313 if (!dp) {
1314 /* DAD wasn't started yet */
1315 return;
1316 }
1317
1318 nd6_dad_stoptimer(dp);
1319
1320 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list);
1321 free(dp, M_IP6NDP);
1322 dp = NULL;
1323 ifa_free(ifa);
1324 }
1325
1326 static void
1327 nd6_dad_timer(struct dadq *dp)
1328 {
1329 CURVNET_SET(dp->dad_vnet);
1330 int s;
1331 struct ifaddr *ifa = dp->dad_ifa;
1332 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1333 char ip6buf[INET6_ADDRSTRLEN];
1334
1335 s = splnet(); /* XXX */
1336
1337 /* Sanity check */
1338 if (ia == NULL) {
1339 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n");
1340 goto done;
1341 }
1342 if (ia->ia6_flags & IN6_IFF_DUPLICATED) {
1343 log(LOG_ERR, "nd6_dad_timer: called with duplicated address "
1344 "%s(%s)\n",
1345 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1346 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1347 goto done;
1348 }
1349 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) {
1350 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address "
1351 "%s(%s)\n",
1352 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1353 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
1354 goto done;
1355 }
1356
1357 /* timeouted with IFF_{RUNNING,UP} check */
1358 if (dp->dad_ns_tcount > V_dad_maxtry) {
1359 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n",
1360 if_name(ifa->ifa_ifp)));
1361
1362 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list);
1363 free(dp, M_IP6NDP);
1364 dp = NULL;
1365 ifa_free(ifa);
1366 goto done;
1367 }
1368
1369 /* Need more checks? */
1370 if (dp->dad_ns_ocount < dp->dad_count) {
1371 /*
1372 * We have more NS to go. Send NS packet for DAD.
1373 */
1374 nd6_dad_ns_output(dp, ifa);
1375 nd6_dad_starttimer(dp,
1376 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
1377 } else {
1378 /*
1379 * We have transmitted sufficient number of DAD packets.
1380 * See what we've got.
1381 */
1382 int duplicate;
1383
1384 duplicate = 0;
1385
1386 if (dp->dad_na_icount) {
1387 /*
1388 * the check is in nd6_dad_na_input(),
1389 * but just in case
1390 */
1391 duplicate++;
1392 }
1393
1394 if (dp->dad_ns_icount) {
1395 /* We've seen NS, means DAD has failed. */
1396 duplicate++;
1397 }
1398
1399 if (duplicate) {
1400 /* (*dp) will be freed in nd6_dad_duplicated() */
1401 dp = NULL;
1402 nd6_dad_duplicated(ifa);
1403 } else {
1404 /*
1405 * We are done with DAD. No NA came, no NS came.
1406 * No duplicate address found.
1407 */
1408 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1409
1410 nd6log((LOG_DEBUG,
1411 "%s: DAD complete for %s - no duplicates found\n",
1412 if_name(ifa->ifa_ifp),
1413 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)));
1414
1415 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list);
1416 free(dp, M_IP6NDP);
1417 dp = NULL;
1418 ifa_free(ifa);
1419 }
1420 }
1421
1422 done:
1423 splx(s);
1424 CURVNET_RESTORE();
1425 }
1426
1427 void
1428 nd6_dad_duplicated(struct ifaddr *ifa)
1429 {
1430 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1431 struct ifnet *ifp;
1432 struct dadq *dp;
1433 char ip6buf[INET6_ADDRSTRLEN];
1434
1435 dp = nd6_dad_find(ifa);
1436 if (dp == NULL) {
1437 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n");
1438 return;
1439 }
1440
1441 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: "
1442 "NS in/out=%d/%d, NA in=%d\n",
1443 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr),
1444 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount);
1445
1446 ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
1447 ia->ia6_flags |= IN6_IFF_DUPLICATED;
1448
1449 /* We are done with DAD, with duplicate address found. (failure) */
1450 nd6_dad_stoptimer(dp);
1451
1452 ifp = ifa->ifa_ifp;
1453 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n",
1454 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr));
1455 log(LOG_ERR, "%s: manual intervention required\n",
1456 if_name(ifp));
1457
1458 /*
1459 * If the address is a link-local address formed from an interface
1460 * identifier based on the hardware address which is supposed to be
1461 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP
1462 * operation on the interface SHOULD be disabled.
1463 * [RFC 4862, Section 5.4.5]
1464 */
1465 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) {
1466 struct in6_addr in6;
1467
1468 /*
1469 * To avoid over-reaction, we only apply this logic when we are
1470 * very sure that hardware addresses are supposed to be unique.
1471 */
1472 switch (ifp->if_type) {
1473 case IFT_ETHER:
1474 case IFT_FDDI:
1475 case IFT_ATM:
1476 case IFT_IEEE1394:
1477 #ifdef IFT_IEEE80211
1478 case IFT_IEEE80211:
1479 #endif
1480 case IFT_INFINIBAND:
1481 in6 = ia->ia_addr.sin6_addr;
1482 if (in6_get_hw_ifid(ifp, &in6) == 0 &&
1483 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) {
1484 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED;
1485 log(LOG_ERR, "%s: possible hardware address "
1486 "duplication detected, disable IPv6\n",
1487 if_name(ifp));
1488 }
1489 break;
1490 }
1491 }
1492
1493 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list);
1494 free(dp, M_IP6NDP);
1495 dp = NULL;
1496 ifa_free(ifa);
1497 }
1498
1499 static void
1500 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa)
1501 {
1502 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
1503 struct ifnet *ifp = ifa->ifa_ifp;
1504
1505 dp->dad_ns_tcount++;
1506 if ((ifp->if_flags & IFF_UP) == 0) {
1507 return;
1508 }
1509 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
1510 return;
1511 }
1512
1513 dp->dad_ns_ocount++;
1514 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1);
1515 }
1516
1517 static void
1518 nd6_dad_ns_input(struct ifaddr *ifa)
1519 {
1520 struct in6_ifaddr *ia;
1521 struct ifnet *ifp;
1522 const struct in6_addr *taddr6;
1523 struct dadq *dp;
1524 int duplicate;
1525
1526 if (ifa == NULL)
1527 panic("ifa == NULL in nd6_dad_ns_input");
1528
1529 ia = (struct in6_ifaddr *)ifa;
1530 ifp = ifa->ifa_ifp;
1531 taddr6 = &ia->ia_addr.sin6_addr;
1532 duplicate = 0;
1533 dp = nd6_dad_find(ifa);
1534
1535 /* Quickhack - completely ignore DAD NS packets */
1536 if (V_dad_ignore_ns) {
1537 char ip6buf[INET6_ADDRSTRLEN];
1538 nd6log((LOG_INFO,
1539 "nd6_dad_ns_input: ignoring DAD NS packet for "
1540 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6),
1541 if_name(ifa->ifa_ifp)));
1542 return;
1543 }
1544
1545 /*
1546 * if I'm yet to start DAD, someone else started using this address
1547 * first. I have a duplicate and you win.
1548 */
1549 if (dp == NULL || dp->dad_ns_ocount == 0)
1550 duplicate++;
1551
1552 /* XXX more checks for loopback situation - see nd6_dad_timer too */
1553
1554 if (duplicate) {
1555 dp = NULL; /* will be freed in nd6_dad_duplicated() */
1556 nd6_dad_duplicated(ifa);
1557 } else {
1558 /*
1559 * not sure if I got a duplicate.
1560 * increment ns count and see what happens.
1561 */
1562 if (dp)
1563 dp->dad_ns_icount++;
1564 }
1565 }
1566
1567 static void
1568 nd6_dad_na_input(struct ifaddr *ifa)
1569 {
1570 struct dadq *dp;
1571
1572 if (ifa == NULL)
1573 panic("ifa == NULL in nd6_dad_na_input");
1574
1575 dp = nd6_dad_find(ifa);
1576 if (dp)
1577 dp->dad_na_icount++;
1578
1579 /* remove the address. */
1580 nd6_dad_duplicated(ifa);
1581 }
Cache object: 10fb30fbd79026868c900b876ba44669
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