FreeBSD/Linux Kernel Cross Reference
sys/netinet6/icmp6.c
1 /* $FreeBSD: releng/6.0/sys/netinet6/icmp6.c 146228 2005-05-15 02:28:30Z gnn $ */
2 /* $KAME: icmp6.c,v 1.211 2001/04/04 05:56:20 itojun 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 /*-
34 * Copyright (c) 1982, 1986, 1988, 1993
35 * The Regents of the University of California. All rights reserved.
36 *
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
39 * are met:
40 * 1. Redistributions of source code must retain the above copyright
41 * notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above copyright
43 * notice, this list of conditions and the following disclaimer in the
44 * documentation and/or other materials provided with the distribution.
45 * 4. Neither the name of the University nor the names of its contributors
46 * may be used to endorse or promote products derived from this software
47 * without specific prior written permission.
48 *
49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59 * SUCH DAMAGE.
60 *
61 * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94
62 */
63
64 #include "opt_inet.h"
65 #include "opt_inet6.h"
66 #include "opt_ipsec.h"
67
68 #include <sys/param.h>
69 #include <sys/domain.h>
70 #include <sys/kernel.h>
71 #include <sys/lock.h>
72 #include <sys/malloc.h>
73 #include <sys/mbuf.h>
74 #include <sys/protosw.h>
75 #include <sys/signalvar.h>
76 #include <sys/socket.h>
77 #include <sys/socketvar.h>
78 #include <sys/sx.h>
79 #include <sys/syslog.h>
80 #include <sys/systm.h>
81 #include <sys/time.h>
82
83 #include <net/if.h>
84 #include <net/if_dl.h>
85 #include <net/if_types.h>
86 #include <net/route.h>
87
88 #include <netinet/in.h>
89 #include <netinet/in_pcb.h>
90 #include <netinet/in_var.h>
91 #include <netinet/ip6.h>
92 #include <netinet/icmp6.h>
93 #include <netinet/tcp_var.h>
94 #include <netinet6/in6_ifattach.h>
95 #include <netinet6/in6_pcb.h>
96 #include <netinet6/ip6protosw.h>
97 #include <netinet6/ip6_var.h>
98 #include <netinet6/mld6_var.h>
99 #include <netinet6/nd6.h>
100
101 #ifdef IPSEC
102 #include <netinet6/ipsec.h>
103 #include <netkey/key.h>
104 #endif
105
106 #ifdef FAST_IPSEC
107 #include <netipsec/ipsec.h>
108 #include <netipsec/key.h>
109 #endif
110
111 #include <net/net_osdep.h>
112
113 extern struct domain inet6domain;
114
115 struct icmp6stat icmp6stat;
116
117 extern struct inpcbinfo ripcbinfo;
118 extern struct inpcbhead ripcb;
119 extern int icmp6errppslim;
120 static int icmp6errpps_count = 0;
121 static struct timeval icmp6errppslim_last;
122 extern int icmp6_nodeinfo;
123
124 static void icmp6_errcount __P((struct icmp6errstat *, int, int));
125 static int icmp6_rip6_input __P((struct mbuf **, int));
126 static int icmp6_ratelimit __P((const struct in6_addr *, const int, const int));
127 static const char *icmp6_redirect_diag __P((struct in6_addr *,
128 struct in6_addr *, struct in6_addr *));
129 static struct mbuf *ni6_input __P((struct mbuf *, int));
130 static struct mbuf *ni6_nametodns __P((const char *, int, int));
131 static int ni6_dnsmatch __P((const char *, int, const char *, int));
132 static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *,
133 struct ifnet **, char *));
134 static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *,
135 struct ifnet *, int));
136 static int icmp6_notify_error __P((struct mbuf **, int, int, int));
137
138 #ifdef COMPAT_RFC1885
139 static struct route_in6 icmp6_reflect_rt;
140 #endif
141
142
143 void
144 icmp6_init()
145 {
146 mld6_init();
147 }
148
149 static void
150 icmp6_errcount(stat, type, code)
151 struct icmp6errstat *stat;
152 int type, code;
153 {
154 switch (type) {
155 case ICMP6_DST_UNREACH:
156 switch (code) {
157 case ICMP6_DST_UNREACH_NOROUTE:
158 stat->icp6errs_dst_unreach_noroute++;
159 return;
160 case ICMP6_DST_UNREACH_ADMIN:
161 stat->icp6errs_dst_unreach_admin++;
162 return;
163 case ICMP6_DST_UNREACH_BEYONDSCOPE:
164 stat->icp6errs_dst_unreach_beyondscope++;
165 return;
166 case ICMP6_DST_UNREACH_ADDR:
167 stat->icp6errs_dst_unreach_addr++;
168 return;
169 case ICMP6_DST_UNREACH_NOPORT:
170 stat->icp6errs_dst_unreach_noport++;
171 return;
172 }
173 break;
174 case ICMP6_PACKET_TOO_BIG:
175 stat->icp6errs_packet_too_big++;
176 return;
177 case ICMP6_TIME_EXCEEDED:
178 switch (code) {
179 case ICMP6_TIME_EXCEED_TRANSIT:
180 stat->icp6errs_time_exceed_transit++;
181 return;
182 case ICMP6_TIME_EXCEED_REASSEMBLY:
183 stat->icp6errs_time_exceed_reassembly++;
184 return;
185 }
186 break;
187 case ICMP6_PARAM_PROB:
188 switch (code) {
189 case ICMP6_PARAMPROB_HEADER:
190 stat->icp6errs_paramprob_header++;
191 return;
192 case ICMP6_PARAMPROB_NEXTHEADER:
193 stat->icp6errs_paramprob_nextheader++;
194 return;
195 case ICMP6_PARAMPROB_OPTION:
196 stat->icp6errs_paramprob_option++;
197 return;
198 }
199 break;
200 case ND_REDIRECT:
201 stat->icp6errs_redirect++;
202 return;
203 }
204 stat->icp6errs_unknown++;
205 }
206
207 /*
208 * Generate an error packet of type error in response to bad IP6 packet.
209 */
210 void
211 icmp6_error(m, type, code, param)
212 struct mbuf *m;
213 int type, code, param;
214 {
215 struct ip6_hdr *oip6, *nip6;
216 struct icmp6_hdr *icmp6;
217 u_int preplen;
218 int off;
219 int nxt;
220
221 icmp6stat.icp6s_error++;
222
223 /* count per-type-code statistics */
224 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code);
225
226 #ifdef M_DECRYPTED /*not openbsd*/
227 if (m->m_flags & M_DECRYPTED) {
228 icmp6stat.icp6s_canterror++;
229 goto freeit;
230 }
231 #endif
232
233 #ifndef PULLDOWN_TEST
234 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), );
235 #else
236 if (m->m_len < sizeof(struct ip6_hdr)) {
237 m = m_pullup(m, sizeof(struct ip6_hdr));
238 if (m == NULL)
239 return;
240 }
241 #endif
242 oip6 = mtod(m, struct ip6_hdr *);
243
244 /*
245 * If the destination address of the erroneous packet is a multicast
246 * address, or the packet was sent using link-layer multicast,
247 * we should basically suppress sending an error (RFC 2463, Section
248 * 2.4).
249 * We have two exceptions (the item e.2 in that section):
250 * - the Pakcet Too Big message can be sent for path MTU discovery.
251 * - the Parameter Problem Message that can be allowed an icmp6 error
252 * in the option type field. This check has been done in
253 * ip6_unknown_opt(), so we can just check the type and code.
254 */
255 if ((m->m_flags & (M_BCAST|M_MCAST) ||
256 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) &&
257 (type != ICMP6_PACKET_TOO_BIG &&
258 (type != ICMP6_PARAM_PROB ||
259 code != ICMP6_PARAMPROB_OPTION)))
260 goto freeit;
261
262 /*
263 * RFC 2463, 2.4 (e.5): source address check.
264 * XXX: the case of anycast source?
265 */
266 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) ||
267 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src))
268 goto freeit;
269
270 /*
271 * If we are about to send ICMPv6 against ICMPv6 error/redirect,
272 * don't do it.
273 */
274 nxt = -1;
275 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
276 if (off >= 0 && nxt == IPPROTO_ICMPV6) {
277 struct icmp6_hdr *icp;
278
279 #ifndef PULLDOWN_TEST
280 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), );
281 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
282 #else
283 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off,
284 sizeof(*icp));
285 if (icp == NULL) {
286 icmp6stat.icp6s_tooshort++;
287 return;
288 }
289 #endif
290 if (icp->icmp6_type < ICMP6_ECHO_REQUEST ||
291 icp->icmp6_type == ND_REDIRECT) {
292 /*
293 * ICMPv6 error
294 * Special case: for redirect (which is
295 * informational) we must not send icmp6 error.
296 */
297 icmp6stat.icp6s_canterror++;
298 goto freeit;
299 } else {
300 /* ICMPv6 informational - send the error */
301 }
302 } else {
303 /* non-ICMPv6 - send the error */
304 }
305
306 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */
307
308 /* Finally, do rate limitation check. */
309 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) {
310 icmp6stat.icp6s_toofreq++;
311 goto freeit;
312 }
313
314 /*
315 * OK, ICMP6 can be generated.
316 */
317
318 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN)
319 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len);
320
321 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
322 M_PREPEND(m, preplen, M_DONTWAIT);
323 if (m && m->m_len < preplen)
324 m = m_pullup(m, preplen);
325 if (m == NULL) {
326 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__));
327 return;
328 }
329
330 nip6 = mtod(m, struct ip6_hdr *);
331 nip6->ip6_src = oip6->ip6_src;
332 nip6->ip6_dst = oip6->ip6_dst;
333
334 in6_clearscope(&oip6->ip6_src);
335 in6_clearscope(&oip6->ip6_dst);
336
337 icmp6 = (struct icmp6_hdr *)(nip6 + 1);
338 icmp6->icmp6_type = type;
339 icmp6->icmp6_code = code;
340 icmp6->icmp6_pptr = htonl((u_int32_t)param);
341
342 /*
343 * icmp6_reflect() is designed to be in the input path.
344 * icmp6_error() can be called from both input and outut path,
345 * and if we are in output path rcvif could contain bogus value.
346 * clear m->m_pkthdr.rcvif for safety, we should have enough scope
347 * information in ip header (nip6).
348 */
349 m->m_pkthdr.rcvif = NULL;
350
351 icmp6stat.icp6s_outhist[type]++;
352 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */
353
354 return;
355
356 freeit:
357 /*
358 * If we can't tell wheter or not we can generate ICMP6, free it.
359 */
360 m_freem(m);
361 }
362
363 /*
364 * Process a received ICMP6 message.
365 */
366 int
367 icmp6_input(mp, offp, proto)
368 struct mbuf **mp;
369 int *offp, proto;
370 {
371 struct mbuf *m = *mp, *n;
372 struct ip6_hdr *ip6, *nip6;
373 struct icmp6_hdr *icmp6, *nicmp6;
374 int off = *offp;
375 int icmp6len = m->m_pkthdr.len - *offp;
376 int code, sum, noff;
377
378 #ifndef PULLDOWN_TEST
379 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE);
380 /* m might change if M_LOOP. So, call mtod after this */
381 #endif
382
383 /*
384 * Locate icmp6 structure in mbuf, and check
385 * that not corrupted and of at least minimum length
386 */
387
388 ip6 = mtod(m, struct ip6_hdr *);
389 if (icmp6len < sizeof(struct icmp6_hdr)) {
390 icmp6stat.icp6s_tooshort++;
391 goto freeit;
392 }
393
394 /*
395 * calculate the checksum
396 */
397 #ifndef PULLDOWN_TEST
398 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
399 #else
400 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
401 if (icmp6 == NULL) {
402 icmp6stat.icp6s_tooshort++;
403 return IPPROTO_DONE;
404 }
405 #endif
406 code = icmp6->icmp6_code;
407
408 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) {
409 nd6log((LOG_ERR,
410 "ICMP6 checksum error(%d|%x) %s\n",
411 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src)));
412 icmp6stat.icp6s_checksum++;
413 goto freeit;
414 }
415
416 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) {
417 /*
418 * Deliver very specific ICMP6 type only.
419 * This is important to deilver TOOBIG. Otherwise PMTUD
420 * will not work.
421 */
422 switch (icmp6->icmp6_type) {
423 case ICMP6_DST_UNREACH:
424 case ICMP6_PACKET_TOO_BIG:
425 case ICMP6_TIME_EXCEEDED:
426 break;
427 default:
428 goto freeit;
429 }
430 }
431
432 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++;
433 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg);
434 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK)
435 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error);
436
437 switch (icmp6->icmp6_type) {
438 case ICMP6_DST_UNREACH:
439 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach);
440 switch (code) {
441 case ICMP6_DST_UNREACH_NOROUTE:
442 code = PRC_UNREACH_NET;
443 break;
444 case ICMP6_DST_UNREACH_ADMIN:
445 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib);
446 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */
447 break;
448 case ICMP6_DST_UNREACH_ADDR:
449 code = PRC_HOSTDEAD;
450 break;
451 #ifdef COMPAT_RFC1885
452 case ICMP6_DST_UNREACH_NOTNEIGHBOR:
453 code = PRC_UNREACH_SRCFAIL;
454 break;
455 #else
456 case ICMP6_DST_UNREACH_BEYONDSCOPE:
457 /* I mean "source address was incorrect." */
458 code = PRC_PARAMPROB;
459 break;
460 #endif
461 case ICMP6_DST_UNREACH_NOPORT:
462 code = PRC_UNREACH_PORT;
463 break;
464 default:
465 goto badcode;
466 }
467 goto deliver;
468 break;
469
470 case ICMP6_PACKET_TOO_BIG:
471 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig);
472
473 /* validation is made in icmp6_mtudisc_update */
474
475 code = PRC_MSGSIZE;
476
477 /*
478 * Updating the path MTU will be done after examining
479 * intermediate extension headers.
480 */
481 goto deliver;
482 break;
483
484 case ICMP6_TIME_EXCEEDED:
485 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed);
486 switch (code) {
487 case ICMP6_TIME_EXCEED_TRANSIT:
488 case ICMP6_TIME_EXCEED_REASSEMBLY:
489 code += PRC_TIMXCEED_INTRANS;
490 break;
491 default:
492 goto badcode;
493 }
494 goto deliver;
495 break;
496
497 case ICMP6_PARAM_PROB:
498 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob);
499 switch (code) {
500 case ICMP6_PARAMPROB_NEXTHEADER:
501 code = PRC_UNREACH_PROTOCOL;
502 break;
503 case ICMP6_PARAMPROB_HEADER:
504 case ICMP6_PARAMPROB_OPTION:
505 code = PRC_PARAMPROB;
506 break;
507 default:
508 goto badcode;
509 }
510 goto deliver;
511 break;
512
513 case ICMP6_ECHO_REQUEST:
514 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo);
515 if (code != 0)
516 goto badcode;
517 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) {
518 /* Give up remote */
519 break;
520 }
521 if ((n->m_flags & M_EXT) != 0
522 || n->m_len < off + sizeof(struct icmp6_hdr)) {
523 struct mbuf *n0 = n;
524 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6);
525 int n0len;
526
527 MGETHDR(n, M_DONTWAIT, n0->m_type);
528 n0len = n0->m_pkthdr.len; /* save for use below */
529 if (n)
530 M_MOVE_PKTHDR(n, n0);
531 if (n && maxlen >= MHLEN) {
532 MCLGET(n, M_DONTWAIT);
533 if ((n->m_flags & M_EXT) == 0) {
534 m_free(n);
535 n = NULL;
536 }
537 }
538 if (n == NULL) {
539 /* Give up remote */
540 m_freem(n0);
541 break;
542 }
543 /*
544 * Copy IPv6 and ICMPv6 only.
545 */
546 nip6 = mtod(n, struct ip6_hdr *);
547 bcopy(ip6, nip6, sizeof(struct ip6_hdr));
548 nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
549 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
550 noff = sizeof(struct ip6_hdr);
551 /* new mbuf contains only ipv6+icmpv6 headers */
552 n->m_len = noff + sizeof(struct icmp6_hdr);
553 /*
554 * Adjust mbuf. ip6_plen will be adjusted in
555 * ip6_output().
556 */
557 m_adj(n0, off + sizeof(struct icmp6_hdr));
558 /* recalculate complete packet size */
559 n->m_pkthdr.len = n0len + (noff - off);
560 n->m_next = n0;
561 } else {
562 nip6 = mtod(n, struct ip6_hdr *);
563 nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off);
564 noff = off;
565 }
566 nicmp6->icmp6_type = ICMP6_ECHO_REPLY;
567 nicmp6->icmp6_code = 0;
568 if (n) {
569 icmp6stat.icp6s_reflect++;
570 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++;
571 icmp6_reflect(n, noff);
572 }
573 break;
574
575 case ICMP6_ECHO_REPLY:
576 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply);
577 if (code != 0)
578 goto badcode;
579 break;
580
581 case MLD_LISTENER_QUERY:
582 case MLD_LISTENER_REPORT:
583 if (icmp6len < sizeof(struct mld_hdr))
584 goto badlen;
585 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */
586 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery);
587 else
588 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport);
589 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
590 /* give up local */
591 mld6_input(m, off);
592 m = NULL;
593 goto freeit;
594 }
595 mld6_input(n, off);
596 /* m stays. */
597 break;
598
599 case MLD_LISTENER_DONE:
600 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone);
601 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */
602 goto badlen;
603 break; /* nothing to be done in kernel */
604
605 case MLD_MTRACE_RESP:
606 case MLD_MTRACE:
607 /* XXX: these two are experimental. not officially defined. */
608 /* XXX: per-interface statistics? */
609 break; /* just pass it to applications */
610
611 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */
612 {
613 enum { WRU, FQDN } mode;
614
615 if (!icmp6_nodeinfo)
616 break;
617
618 if (icmp6len == sizeof(struct icmp6_hdr) + 4)
619 mode = WRU;
620 else if (icmp6len >= sizeof(struct icmp6_nodeinfo))
621 mode = FQDN;
622 else
623 goto badlen;
624
625 #define hostnamelen strlen(hostname)
626 if (mode == FQDN) {
627 #ifndef PULLDOWN_TEST
628 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo),
629 IPPROTO_DONE);
630 #endif
631 n = m_copy(m, 0, M_COPYALL);
632 if (n)
633 n = ni6_input(n, off);
634 /* XXX meaningless if n == NULL */
635 noff = sizeof(struct ip6_hdr);
636 } else {
637 u_char *p;
638 int maxlen, maxhlen;
639
640 if ((icmp6_nodeinfo & 5) != 5)
641 break;
642
643 if (code != 0)
644 goto badcode;
645 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4;
646 if (maxlen >= MCLBYTES) {
647 /* Give up remote */
648 break;
649 }
650 MGETHDR(n, M_DONTWAIT, m->m_type);
651 if (n && maxlen > MHLEN) {
652 MCLGET(n, M_DONTWAIT);
653 if ((n->m_flags & M_EXT) == 0) {
654 m_free(n);
655 n = NULL;
656 }
657 }
658 if (!m_dup_pkthdr(n, m, M_DONTWAIT)) {
659 /*
660 * Previous code did a blind M_COPY_PKTHDR
661 * and said "just for rcvif". If true, then
662 * we could tolerate the dup failing (due to
663 * the deep copy of the tag chain). For now
664 * be conservative and just fail.
665 */
666 m_free(n);
667 n = NULL;
668 }
669 if (n == NULL) {
670 /* Give up remote */
671 break;
672 }
673 n->m_pkthdr.rcvif = NULL;
674 n->m_len = 0;
675 maxhlen = M_TRAILINGSPACE(n) - maxlen;
676 if (maxhlen > hostnamelen)
677 maxhlen = hostnamelen;
678 /*
679 * Copy IPv6 and ICMPv6 only.
680 */
681 nip6 = mtod(n, struct ip6_hdr *);
682 bcopy(ip6, nip6, sizeof(struct ip6_hdr));
683 nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
684 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
685 p = (u_char *)(nicmp6 + 1);
686 bzero(p, 4);
687 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */
688 noff = sizeof(struct ip6_hdr);
689 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
690 sizeof(struct icmp6_hdr) + 4 + maxhlen;
691 nicmp6->icmp6_type = ICMP6_WRUREPLY;
692 nicmp6->icmp6_code = 0;
693 }
694 #undef hostnamelen
695 if (n) {
696 icmp6stat.icp6s_reflect++;
697 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++;
698 icmp6_reflect(n, noff);
699 }
700 break;
701 }
702
703 case ICMP6_WRUREPLY:
704 if (code != 0)
705 goto badcode;
706 break;
707
708 case ND_ROUTER_SOLICIT:
709 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit);
710 if (code != 0)
711 goto badcode;
712 if (icmp6len < sizeof(struct nd_router_solicit))
713 goto badlen;
714 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
715 /* give up local */
716 nd6_rs_input(m, off, icmp6len);
717 m = NULL;
718 goto freeit;
719 }
720 nd6_rs_input(n, off, icmp6len);
721 /* m stays. */
722 break;
723
724 case ND_ROUTER_ADVERT:
725 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert);
726 if (code != 0)
727 goto badcode;
728 if (icmp6len < sizeof(struct nd_router_advert))
729 goto badlen;
730 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
731 /* give up local */
732 nd6_ra_input(m, off, icmp6len);
733 m = NULL;
734 goto freeit;
735 }
736 nd6_ra_input(n, off, icmp6len);
737 /* m stays. */
738 break;
739
740 case ND_NEIGHBOR_SOLICIT:
741 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit);
742 if (code != 0)
743 goto badcode;
744 if (icmp6len < sizeof(struct nd_neighbor_solicit))
745 goto badlen;
746 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
747 /* give up local */
748 nd6_ns_input(m, off, icmp6len);
749 m = NULL;
750 goto freeit;
751 }
752 nd6_ns_input(n, off, icmp6len);
753 /* m stays. */
754 break;
755
756 case ND_NEIGHBOR_ADVERT:
757 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert);
758 if (code != 0)
759 goto badcode;
760 if (icmp6len < sizeof(struct nd_neighbor_advert))
761 goto badlen;
762 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
763 /* give up local */
764 nd6_na_input(m, off, icmp6len);
765 m = NULL;
766 goto freeit;
767 }
768 nd6_na_input(n, off, icmp6len);
769 /* m stays. */
770 break;
771
772 case ND_REDIRECT:
773 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect);
774 if (code != 0)
775 goto badcode;
776 if (icmp6len < sizeof(struct nd_redirect))
777 goto badlen;
778 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
779 /* give up local */
780 icmp6_redirect_input(m, off);
781 m = NULL;
782 goto freeit;
783 }
784 icmp6_redirect_input(n, off);
785 /* m stays. */
786 break;
787
788 case ICMP6_ROUTER_RENUMBERING:
789 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND &&
790 code != ICMP6_ROUTER_RENUMBERING_RESULT)
791 goto badcode;
792 if (icmp6len < sizeof(struct icmp6_router_renum))
793 goto badlen;
794 break;
795
796 default:
797 nd6log((LOG_DEBUG,
798 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n",
799 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src),
800 ip6_sprintf(&ip6->ip6_dst),
801 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0));
802 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) {
803 /* ICMPv6 error: MUST deliver it by spec... */
804 code = PRC_NCMDS;
805 /* deliver */
806 } else {
807 /* ICMPv6 informational: MUST not deliver */
808 break;
809 }
810 deliver:
811 if (icmp6_notify_error(&m, off, icmp6len, code)) {
812 /* In this case, m should've been freed. */
813 return (IPPROTO_DONE);
814 }
815 break;
816
817 badcode:
818 icmp6stat.icp6s_badcode++;
819 break;
820
821 badlen:
822 icmp6stat.icp6s_badlen++;
823 break;
824 }
825
826 /* deliver the packet to appropriate sockets */
827 icmp6_rip6_input(&m, *offp);
828
829 return IPPROTO_DONE;
830
831 freeit:
832 m_freem(m);
833 return IPPROTO_DONE;
834 }
835
836 static int
837 icmp6_notify_error(mp, off, icmp6len, code)
838 struct mbuf **mp;
839 int off, icmp6len, code;
840 {
841 struct mbuf *m = *mp;
842 struct icmp6_hdr *icmp6;
843 struct ip6_hdr *eip6;
844 u_int32_t notifymtu;
845 struct sockaddr_in6 icmp6src, icmp6dst;
846
847 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) {
848 icmp6stat.icp6s_tooshort++;
849 goto freeit;
850 }
851 #ifndef PULLDOWN_TEST
852 IP6_EXTHDR_CHECK(m, off,
853 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1);
854 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
855 #else
856 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
857 sizeof(*icmp6) + sizeof(struct ip6_hdr));
858 if (icmp6 == NULL) {
859 icmp6stat.icp6s_tooshort++;
860 return (-1);
861 }
862 #endif
863 eip6 = (struct ip6_hdr *)(icmp6 + 1);
864
865 /* Detect the upper level protocol */
866 {
867 void (*ctlfunc) __P((int, struct sockaddr *, void *));
868 u_int8_t nxt = eip6->ip6_nxt;
869 int eoff = off + sizeof(struct icmp6_hdr) +
870 sizeof(struct ip6_hdr);
871 struct ip6ctlparam ip6cp;
872 struct in6_addr *finaldst = NULL;
873 int icmp6type = icmp6->icmp6_type;
874 struct ip6_frag *fh;
875 struct ip6_rthdr *rth;
876 struct ip6_rthdr0 *rth0;
877 int rthlen;
878
879 while (1) { /* XXX: should avoid infinite loop explicitly? */
880 struct ip6_ext *eh;
881
882 switch (nxt) {
883 case IPPROTO_HOPOPTS:
884 case IPPROTO_DSTOPTS:
885 case IPPROTO_AH:
886 #ifndef PULLDOWN_TEST
887 IP6_EXTHDR_CHECK(m, 0,
888 eoff + sizeof(struct ip6_ext), -1);
889 eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff);
890 #else
891 IP6_EXTHDR_GET(eh, struct ip6_ext *, m,
892 eoff, sizeof(*eh));
893 if (eh == NULL) {
894 icmp6stat.icp6s_tooshort++;
895 return (-1);
896 }
897 #endif
898
899 if (nxt == IPPROTO_AH)
900 eoff += (eh->ip6e_len + 2) << 2;
901 else
902 eoff += (eh->ip6e_len + 1) << 3;
903 nxt = eh->ip6e_nxt;
904 break;
905 case IPPROTO_ROUTING:
906 /*
907 * When the erroneous packet contains a
908 * routing header, we should examine the
909 * header to determine the final destination.
910 * Otherwise, we can't properly update
911 * information that depends on the final
912 * destination (e.g. path MTU).
913 */
914 #ifndef PULLDOWN_TEST
915 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1);
916 rth = (struct ip6_rthdr *)
917 (mtod(m, caddr_t) + eoff);
918 #else
919 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m,
920 eoff, sizeof(*rth));
921 if (rth == NULL) {
922 icmp6stat.icp6s_tooshort++;
923 return (-1);
924 }
925 #endif
926 rthlen = (rth->ip6r_len + 1) << 3;
927 /*
928 * XXX: currently there is no
929 * officially defined type other
930 * than type-0.
931 * Note that if the segment left field
932 * is 0, all intermediate hops must
933 * have been passed.
934 */
935 if (rth->ip6r_segleft &&
936 rth->ip6r_type == IPV6_RTHDR_TYPE_0) {
937 int hops;
938
939 #ifndef PULLDOWN_TEST
940 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1);
941 rth0 = (struct ip6_rthdr0 *)
942 (mtod(m, caddr_t) + eoff);
943 #else
944 IP6_EXTHDR_GET(rth0,
945 struct ip6_rthdr0 *, m,
946 eoff, rthlen);
947 if (rth0 == NULL) {
948 icmp6stat.icp6s_tooshort++;
949 return (-1);
950 }
951 #endif
952 /* just ignore a bogus header */
953 if ((rth0->ip6r0_len % 2) == 0 &&
954 (hops = rth0->ip6r0_len/2))
955 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1);
956 }
957 eoff += rthlen;
958 nxt = rth->ip6r_nxt;
959 break;
960 case IPPROTO_FRAGMENT:
961 #ifndef PULLDOWN_TEST
962 IP6_EXTHDR_CHECK(m, 0, eoff +
963 sizeof(struct ip6_frag), -1);
964 fh = (struct ip6_frag *)(mtod(m, caddr_t) +
965 eoff);
966 #else
967 IP6_EXTHDR_GET(fh, struct ip6_frag *, m,
968 eoff, sizeof(*fh));
969 if (fh == NULL) {
970 icmp6stat.icp6s_tooshort++;
971 return (-1);
972 }
973 #endif
974 /*
975 * Data after a fragment header is meaningless
976 * unless it is the first fragment, but
977 * we'll go to the notify label for path MTU
978 * discovery.
979 */
980 if (fh->ip6f_offlg & IP6F_OFF_MASK)
981 goto notify;
982
983 eoff += sizeof(struct ip6_frag);
984 nxt = fh->ip6f_nxt;
985 break;
986 default:
987 /*
988 * This case includes ESP and the No Next
989 * Header. In such cases going to the notify
990 * label does not have any meaning
991 * (i.e. ctlfunc will be NULL), but we go
992 * anyway since we might have to update
993 * path MTU information.
994 */
995 goto notify;
996 }
997 }
998 notify:
999 #ifndef PULLDOWN_TEST
1000 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
1001 #else
1002 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
1003 sizeof(*icmp6) + sizeof(struct ip6_hdr));
1004 if (icmp6 == NULL) {
1005 icmp6stat.icp6s_tooshort++;
1006 return (-1);
1007 }
1008 #endif
1009
1010 /*
1011 * retrieve parameters from the inner IPv6 header, and convert
1012 * them into sockaddr structures.
1013 * XXX: there is no guarantee that the source or destination
1014 * addresses of the inner packet are in the same scope as
1015 * the addresses of the icmp packet. But there is no other
1016 * way to determine the zone.
1017 */
1018 eip6 = (struct ip6_hdr *)(icmp6 + 1);
1019
1020 bzero(&icmp6dst, sizeof(icmp6dst));
1021 icmp6dst.sin6_len = sizeof(struct sockaddr_in6);
1022 icmp6dst.sin6_family = AF_INET6;
1023 if (finaldst == NULL)
1024 icmp6dst.sin6_addr = eip6->ip6_dst;
1025 else
1026 icmp6dst.sin6_addr = *finaldst;
1027 if (in6_addr2zoneid(m->m_pkthdr.rcvif, &icmp6dst.sin6_addr,
1028 &icmp6dst.sin6_scope_id))
1029 goto freeit;
1030 if (in6_embedscope(&icmp6dst.sin6_addr, &icmp6dst,
1031 NULL, NULL)) {
1032 /* should be impossible */
1033 nd6log((LOG_DEBUG,
1034 "icmp6_notify_error: in6_embedscope failed\n"));
1035 goto freeit;
1036 }
1037
1038 /*
1039 * retrieve parameters from the inner IPv6 header, and convert
1040 * them into sockaddr structures.
1041 */
1042 bzero(&icmp6src, sizeof(icmp6src));
1043 icmp6src.sin6_len = sizeof(struct sockaddr_in6);
1044 icmp6src.sin6_family = AF_INET6;
1045 icmp6src.sin6_addr = eip6->ip6_src;
1046 if (in6_addr2zoneid(m->m_pkthdr.rcvif, &icmp6src.sin6_addr,
1047 &icmp6src.sin6_scope_id)) {
1048 goto freeit;
1049 }
1050 if (in6_embedscope(&icmp6src.sin6_addr, &icmp6src,
1051 NULL, NULL)) {
1052 /* should be impossible */
1053 nd6log((LOG_DEBUG,
1054 "icmp6_notify_error: in6_embedscope failed\n"));
1055 goto freeit;
1056 }
1057 icmp6src.sin6_flowinfo = (eip6->ip6_flow & IPV6_FLOWLABEL_MASK);
1058
1059 if (finaldst == NULL)
1060 finaldst = &eip6->ip6_dst;
1061 ip6cp.ip6c_m = m;
1062 ip6cp.ip6c_icmp6 = icmp6;
1063 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1);
1064 ip6cp.ip6c_off = eoff;
1065 ip6cp.ip6c_finaldst = finaldst;
1066 ip6cp.ip6c_src = &icmp6src;
1067 ip6cp.ip6c_nxt = nxt;
1068
1069 if (icmp6type == ICMP6_PACKET_TOO_BIG) {
1070 notifymtu = ntohl(icmp6->icmp6_mtu);
1071 ip6cp.ip6c_cmdarg = (void *)¬ifymtu;
1072 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/
1073 }
1074
1075 ctlfunc = (void (*) __P((int, struct sockaddr *, void *)))
1076 (inet6sw[ip6_protox[nxt]].pr_ctlinput);
1077 if (ctlfunc) {
1078 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst,
1079 &ip6cp);
1080 }
1081 }
1082 *mp = m;
1083 return (0);
1084
1085 freeit:
1086 m_freem(m);
1087 return (-1);
1088 }
1089
1090 void
1091 icmp6_mtudisc_update(ip6cp, validated)
1092 struct ip6ctlparam *ip6cp;
1093 int validated;
1094 {
1095 struct in6_addr *dst = ip6cp->ip6c_finaldst;
1096 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6;
1097 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */
1098 u_int mtu = ntohl(icmp6->icmp6_mtu);
1099 struct in_conninfo inc;
1100
1101 #if 0
1102 /*
1103 * RFC2460 section 5, last paragraph.
1104 * even though minimum link MTU for IPv6 is IPV6_MMTU,
1105 * we may see ICMPv6 too big with mtu < IPV6_MMTU
1106 * due to packet translator in the middle.
1107 * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for
1108 * special handling.
1109 */
1110 if (mtu < IPV6_MMTU)
1111 return;
1112 #endif
1113
1114 /*
1115 * we reject ICMPv6 too big with abnormally small value.
1116 * XXX what is the good definition of "abnormally small"?
1117 */
1118 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8)
1119 return;
1120
1121 if (!validated)
1122 return;
1123
1124 bzero(&inc, sizeof(inc));
1125 inc.inc_flags = 1; /* IPv6 */
1126 inc.inc6_faddr = *dst;
1127 /* XXX normally, this won't happen */
1128 if (IN6_IS_ADDR_LINKLOCAL(dst)) {
1129 inc.inc6_faddr.s6_addr16[1] =
1130 htons(m->m_pkthdr.rcvif->if_index);
1131 }
1132
1133 if (mtu < tcp_maxmtu6(&inc)) {
1134 tcp_hc_updatemtu(&inc, mtu);
1135 icmp6stat.icp6s_pmtuchg++;
1136 }
1137 }
1138
1139 /*
1140 * Process a Node Information Query packet, based on
1141 * draft-ietf-ipngwg-icmp-name-lookups-07.
1142 *
1143 * Spec incompatibilities:
1144 * - IPv6 Subject address handling
1145 * - IPv4 Subject address handling support missing
1146 * - Proxy reply (answer even if it's not for me)
1147 * - joins NI group address at in6_ifattach() time only, does not cope
1148 * with hostname changes by sethostname(3)
1149 */
1150 #define hostnamelen strlen(hostname)
1151 static struct mbuf *
1152 ni6_input(m, off)
1153 struct mbuf *m;
1154 int off;
1155 {
1156 struct icmp6_nodeinfo *ni6, *nni6;
1157 struct mbuf *n = NULL;
1158 u_int16_t qtype;
1159 int subjlen;
1160 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
1161 struct ni_reply_fqdn *fqdn;
1162 int addrs; /* for NI_QTYPE_NODEADDR */
1163 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */
1164 struct sockaddr_in6 sin6_sbj; /* subject address */
1165 struct ip6_hdr *ip6;
1166 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */
1167 char *subj = NULL;
1168 struct in6_ifaddr *ia6 = NULL;
1169
1170 ip6 = mtod(m, struct ip6_hdr *);
1171 #ifndef PULLDOWN_TEST
1172 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off);
1173 #else
1174 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6));
1175 if (ni6 == NULL) {
1176 /* m is already reclaimed */
1177 return (NULL);
1178 }
1179 #endif
1180
1181 /*
1182 * Validate IPv6 destination address.
1183 *
1184 * The Responder must discard the Query without further processing
1185 * unless it is one of the Responder's unicast or anycast addresses, or
1186 * a link-local scope multicast address which the Responder has joined.
1187 * [icmp-name-lookups-08, Section 4.]
1188 */
1189 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
1190 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst))
1191 goto bad;
1192 /* else it's a link-local multicast, fine */
1193 } else { /* unicast or anycast */
1194 if ((ia6 = ip6_getdstifaddr(m)) == NULL)
1195 goto bad; /* XXX impossible */
1196
1197 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) &&
1198 !(icmp6_nodeinfo & 4)) {
1199 nd6log((LOG_DEBUG, "ni6_input: ignore node info to "
1200 "a temporary address in %s:%d",
1201 __FILE__, __LINE__));
1202 goto bad;
1203 }
1204 }
1205
1206 /* validate query Subject field. */
1207 qtype = ntohs(ni6->ni_qtype);
1208 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo);
1209 switch (qtype) {
1210 case NI_QTYPE_NOOP:
1211 case NI_QTYPE_SUPTYPES:
1212 /* 07 draft */
1213 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0)
1214 break;
1215 /* FALLTHROUGH */
1216 case NI_QTYPE_FQDN:
1217 case NI_QTYPE_NODEADDR:
1218 switch (ni6->ni_code) {
1219 case ICMP6_NI_SUBJ_IPV6:
1220 #if ICMP6_NI_SUBJ_IPV6 != 0
1221 case 0:
1222 #endif
1223 /*
1224 * backward compatibility - try to accept 03 draft
1225 * format, where no Subject is present.
1226 */
1227 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 &&
1228 subjlen == 0) {
1229 oldfqdn++;
1230 break;
1231 }
1232 #if ICMP6_NI_SUBJ_IPV6 != 0
1233 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6)
1234 goto bad;
1235 #endif
1236
1237 if (subjlen != sizeof(struct in6_addr))
1238 goto bad;
1239
1240 /*
1241 * Validate Subject address.
1242 *
1243 * Not sure what exactly "address belongs to the node"
1244 * means in the spec, is it just unicast, or what?
1245 *
1246 * At this moment we consider Subject address as
1247 * "belong to the node" if the Subject address equals
1248 * to the IPv6 destination address; validation for
1249 * IPv6 destination address should have done enough
1250 * check for us.
1251 *
1252 * We do not do proxy at this moment.
1253 */
1254 /* m_pulldown instead of copy? */
1255 bzero(&sin6_sbj, sizeof(sin6_sbj));
1256 sin6_sbj.sin6_family = AF_INET6;
1257 sin6_sbj.sin6_len = sizeof(sin6_sbj);
1258 m_copydata(m, off + sizeof(struct icmp6_nodeinfo),
1259 subjlen, (caddr_t)&sin6_sbj.sin6_addr);
1260 if (in6_addr2zoneid(m->m_pkthdr.rcvif,
1261 &sin6_sbj.sin6_addr, &sin6_sbj.sin6_scope_id)) {
1262 goto bad;
1263 }
1264 if (in6_embedscope(&sin6_sbj.sin6_addr, &sin6_sbj,
1265 NULL, NULL))
1266 goto bad; /* XXX should not happen */
1267
1268 subj = (char *)&sin6_sbj;
1269 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
1270 &sin6_sbj.sin6_addr))
1271 break;
1272
1273 /*
1274 * XXX if we are to allow other cases, we should really
1275 * be careful about scope here.
1276 * basically, we should disallow queries toward IPv6
1277 * destination X with subject Y,
1278 * if scope(X) > scope(Y).
1279 * if we allow scope(X) > scope(Y), it will result in
1280 * information leakage across scope boundary.
1281 */
1282 goto bad;
1283
1284 case ICMP6_NI_SUBJ_FQDN:
1285 /*
1286 * Validate Subject name with gethostname(3).
1287 *
1288 * The behavior may need some debate, since:
1289 * - we are not sure if the node has FQDN as
1290 * hostname (returned by gethostname(3)).
1291 * - the code does wildcard match for truncated names.
1292 * however, we are not sure if we want to perform
1293 * wildcard match, if gethostname(3) side has
1294 * truncated hostname.
1295 */
1296 n = ni6_nametodns(hostname, hostnamelen, 0);
1297 if (!n || n->m_next || n->m_len == 0)
1298 goto bad;
1299 IP6_EXTHDR_GET(subj, char *, m,
1300 off + sizeof(struct icmp6_nodeinfo), subjlen);
1301 if (subj == NULL)
1302 goto bad;
1303 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *),
1304 n->m_len)) {
1305 goto bad;
1306 }
1307 m_freem(n);
1308 n = NULL;
1309 break;
1310
1311 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */
1312 default:
1313 goto bad;
1314 }
1315 break;
1316 }
1317
1318 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */
1319 switch (qtype) {
1320 case NI_QTYPE_FQDN:
1321 if ((icmp6_nodeinfo & 1) == 0)
1322 goto bad;
1323 break;
1324 case NI_QTYPE_NODEADDR:
1325 if ((icmp6_nodeinfo & 2) == 0)
1326 goto bad;
1327 break;
1328 }
1329
1330 /* guess reply length */
1331 switch (qtype) {
1332 case NI_QTYPE_NOOP:
1333 break; /* no reply data */
1334 case NI_QTYPE_SUPTYPES:
1335 replylen += sizeof(u_int32_t);
1336 break;
1337 case NI_QTYPE_FQDN:
1338 /* XXX will append an mbuf */
1339 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1340 break;
1341 case NI_QTYPE_NODEADDR:
1342 addrs = ni6_addrs(ni6, m, &ifp, subj);
1343 if ((replylen += addrs * (sizeof(struct in6_addr) +
1344 sizeof(u_int32_t))) > MCLBYTES)
1345 replylen = MCLBYTES; /* XXX: will truncate pkt later */
1346 break;
1347 default:
1348 /*
1349 * XXX: We must return a reply with the ICMP6 code
1350 * `unknown Qtype' in this case. However we regard the case
1351 * as an FQDN query for backward compatibility.
1352 * Older versions set a random value to this field,
1353 * so it rarely varies in the defined qtypes.
1354 * But the mechanism is not reliable...
1355 * maybe we should obsolete older versions.
1356 */
1357 qtype = NI_QTYPE_FQDN;
1358 /* XXX will append an mbuf */
1359 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1360 oldfqdn++;
1361 break;
1362 }
1363
1364 /* allocate an mbuf to reply. */
1365 MGETHDR(n, M_DONTWAIT, m->m_type);
1366 if (n == NULL) {
1367 m_freem(m);
1368 return (NULL);
1369 }
1370 M_MOVE_PKTHDR(n, m); /* just for recvif */
1371 if (replylen > MHLEN) {
1372 if (replylen > MCLBYTES) {
1373 /*
1374 * XXX: should we try to allocate more? But MCLBYTES
1375 * is probably much larger than IPV6_MMTU...
1376 */
1377 goto bad;
1378 }
1379 MCLGET(n, M_DONTWAIT);
1380 if ((n->m_flags & M_EXT) == 0) {
1381 goto bad;
1382 }
1383 }
1384 n->m_pkthdr.len = n->m_len = replylen;
1385
1386 /* copy mbuf header and IPv6 + Node Information base headers */
1387 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr));
1388 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1);
1389 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo));
1390
1391 /* qtype dependent procedure */
1392 switch (qtype) {
1393 case NI_QTYPE_NOOP:
1394 nni6->ni_code = ICMP6_NI_SUCCESS;
1395 nni6->ni_flags = 0;
1396 break;
1397 case NI_QTYPE_SUPTYPES:
1398 {
1399 u_int32_t v;
1400 nni6->ni_code = ICMP6_NI_SUCCESS;
1401 nni6->ni_flags = htons(0x0000); /* raw bitmap */
1402 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */
1403 v = (u_int32_t)htonl(0x0000000f);
1404 bcopy(&v, nni6 + 1, sizeof(u_int32_t));
1405 break;
1406 }
1407 case NI_QTYPE_FQDN:
1408 nni6->ni_code = ICMP6_NI_SUCCESS;
1409 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) +
1410 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo));
1411 nni6->ni_flags = 0; /* XXX: meaningless TTL */
1412 fqdn->ni_fqdn_ttl = 0; /* ditto. */
1413 /*
1414 * XXX do we really have FQDN in variable "hostname"?
1415 */
1416 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn);
1417 if (n->m_next == NULL)
1418 goto bad;
1419 /* XXX we assume that n->m_next is not a chain */
1420 if (n->m_next->m_next != NULL)
1421 goto bad;
1422 n->m_pkthdr.len += n->m_next->m_len;
1423 break;
1424 case NI_QTYPE_NODEADDR:
1425 {
1426 int lenlim, copied;
1427
1428 nni6->ni_code = ICMP6_NI_SUCCESS;
1429 n->m_pkthdr.len = n->m_len =
1430 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
1431 lenlim = M_TRAILINGSPACE(n);
1432 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim);
1433 /* XXX: reset mbuf length */
1434 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
1435 sizeof(struct icmp6_nodeinfo) + copied;
1436 break;
1437 }
1438 default:
1439 break; /* XXX impossible! */
1440 }
1441
1442 nni6->ni_type = ICMP6_NI_REPLY;
1443 m_freem(m);
1444 return (n);
1445
1446 bad:
1447 m_freem(m);
1448 if (n)
1449 m_freem(n);
1450 return (NULL);
1451 }
1452 #undef hostnamelen
1453
1454 /*
1455 * make a mbuf with DNS-encoded string. no compression support.
1456 *
1457 * XXX names with less than 2 dots (like "foo" or "foo.section") will be
1458 * treated as truncated name (two \0 at the end). this is a wild guess.
1459 */
1460 static struct mbuf *
1461 ni6_nametodns(name, namelen, old)
1462 const char *name;
1463 int namelen;
1464 int old; /* return pascal string if non-zero */
1465 {
1466 struct mbuf *m;
1467 char *cp, *ep;
1468 const char *p, *q;
1469 int i, len, nterm;
1470
1471 if (old)
1472 len = namelen + 1;
1473 else
1474 len = MCLBYTES;
1475
1476 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */
1477 MGET(m, M_DONTWAIT, MT_DATA);
1478 if (m && len > MLEN) {
1479 MCLGET(m, M_DONTWAIT);
1480 if ((m->m_flags & M_EXT) == 0)
1481 goto fail;
1482 }
1483 if (!m)
1484 goto fail;
1485 m->m_next = NULL;
1486
1487 if (old) {
1488 m->m_len = len;
1489 *mtod(m, char *) = namelen;
1490 bcopy(name, mtod(m, char *) + 1, namelen);
1491 return m;
1492 } else {
1493 m->m_len = 0;
1494 cp = mtod(m, char *);
1495 ep = mtod(m, char *) + M_TRAILINGSPACE(m);
1496
1497 /* if not certain about my name, return empty buffer */
1498 if (namelen == 0)
1499 return m;
1500
1501 /*
1502 * guess if it looks like shortened hostname, or FQDN.
1503 * shortened hostname needs two trailing "\0".
1504 */
1505 i = 0;
1506 for (p = name; p < name + namelen; p++) {
1507 if (*p && *p == '.')
1508 i++;
1509 }
1510 if (i < 2)
1511 nterm = 2;
1512 else
1513 nterm = 1;
1514
1515 p = name;
1516 while (cp < ep && p < name + namelen) {
1517 i = 0;
1518 for (q = p; q < name + namelen && *q && *q != '.'; q++)
1519 i++;
1520 /* result does not fit into mbuf */
1521 if (cp + i + 1 >= ep)
1522 goto fail;
1523 /*
1524 * DNS label length restriction, RFC1035 page 8.
1525 * "i == 0" case is included here to avoid returning
1526 * 0-length label on "foo..bar".
1527 */
1528 if (i <= 0 || i >= 64)
1529 goto fail;
1530 *cp++ = i;
1531 bcopy(p, cp, i);
1532 cp += i;
1533 p = q;
1534 if (p < name + namelen && *p == '.')
1535 p++;
1536 }
1537 /* termination */
1538 if (cp + nterm >= ep)
1539 goto fail;
1540 while (nterm-- > 0)
1541 *cp++ = '\0';
1542 m->m_len = cp - mtod(m, char *);
1543 return m;
1544 }
1545
1546 panic("should not reach here");
1547 /* NOTREACHED */
1548
1549 fail:
1550 if (m)
1551 m_freem(m);
1552 return NULL;
1553 }
1554
1555 /*
1556 * check if two DNS-encoded string matches. takes care of truncated
1557 * form (with \0\0 at the end). no compression support.
1558 * XXX upper/lowercase match (see RFC2065)
1559 */
1560 static int
1561 ni6_dnsmatch(a, alen, b, blen)
1562 const char *a;
1563 int alen;
1564 const char *b;
1565 int blen;
1566 {
1567 const char *a0, *b0;
1568 int l;
1569
1570 /* simplest case - need validation? */
1571 if (alen == blen && bcmp(a, b, alen) == 0)
1572 return 1;
1573
1574 a0 = a;
1575 b0 = b;
1576
1577 /* termination is mandatory */
1578 if (alen < 2 || blen < 2)
1579 return 0;
1580 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0')
1581 return 0;
1582 alen--;
1583 blen--;
1584
1585 while (a - a0 < alen && b - b0 < blen) {
1586 if (a - a0 + 1 > alen || b - b0 + 1 > blen)
1587 return 0;
1588
1589 if ((signed char)a[0] < 0 || (signed char)b[0] < 0)
1590 return 0;
1591 /* we don't support compression yet */
1592 if (a[0] >= 64 || b[0] >= 64)
1593 return 0;
1594
1595 /* truncated case */
1596 if (a[0] == 0 && a - a0 == alen - 1)
1597 return 1;
1598 if (b[0] == 0 && b - b0 == blen - 1)
1599 return 1;
1600 if (a[0] == 0 || b[0] == 0)
1601 return 0;
1602
1603 if (a[0] != b[0])
1604 return 0;
1605 l = a[0];
1606 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen)
1607 return 0;
1608 if (bcmp(a + 1, b + 1, l) != 0)
1609 return 0;
1610
1611 a += 1 + l;
1612 b += 1 + l;
1613 }
1614
1615 if (a - a0 == alen && b - b0 == blen)
1616 return 1;
1617 else
1618 return 0;
1619 }
1620
1621 /*
1622 * calculate the number of addresses to be returned in the node info reply.
1623 */
1624 static int
1625 ni6_addrs(ni6, m, ifpp, subj)
1626 struct icmp6_nodeinfo *ni6;
1627 struct mbuf *m;
1628 struct ifnet **ifpp;
1629 char *subj;
1630 {
1631 struct ifnet *ifp;
1632 struct in6_ifaddr *ifa6;
1633 struct ifaddr *ifa;
1634 struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */
1635 int addrs = 0, addrsofif, iffound = 0;
1636 int niflags = ni6->ni_flags;
1637
1638 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) {
1639 switch (ni6->ni_code) {
1640 case ICMP6_NI_SUBJ_IPV6:
1641 if (subj == NULL) /* must be impossible... */
1642 return (0);
1643 subj_ip6 = (struct sockaddr_in6 *)subj;
1644 break;
1645 default:
1646 /*
1647 * XXX: we only support IPv6 subject address for
1648 * this Qtype.
1649 */
1650 return (0);
1651 }
1652 }
1653
1654 IFNET_RLOCK();
1655 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) {
1656 addrsofif = 0;
1657 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) {
1658 if (ifa->ifa_addr->sa_family != AF_INET6)
1659 continue;
1660 ifa6 = (struct in6_ifaddr *)ifa;
1661
1662 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 &&
1663 IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr,
1664 &ifa6->ia_addr.sin6_addr))
1665 iffound = 1;
1666
1667 /*
1668 * IPv4-mapped addresses can only be returned by a
1669 * Node Information proxy, since they represent
1670 * addresses of IPv4-only nodes, which perforce do
1671 * not implement this protocol.
1672 * [icmp-name-lookups-07, Section 5.4]
1673 * So we don't support NI_NODEADDR_FLAG_COMPAT in
1674 * this function at this moment.
1675 */
1676
1677 /* What do we have to do about ::1? */
1678 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
1679 case IPV6_ADDR_SCOPE_LINKLOCAL:
1680 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
1681 continue;
1682 break;
1683 case IPV6_ADDR_SCOPE_SITELOCAL:
1684 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
1685 continue;
1686 break;
1687 case IPV6_ADDR_SCOPE_GLOBAL:
1688 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
1689 continue;
1690 break;
1691 default:
1692 continue;
1693 }
1694
1695 /*
1696 * check if anycast is okay.
1697 * XXX: just experimental. not in the spec.
1698 */
1699 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 &&
1700 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0)
1701 continue; /* we need only unicast addresses */
1702 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
1703 (icmp6_nodeinfo & 4) == 0) {
1704 continue;
1705 }
1706 addrsofif++; /* count the address */
1707 }
1708 if (iffound) {
1709 *ifpp = ifp;
1710 IFNET_RUNLOCK();
1711 return (addrsofif);
1712 }
1713
1714 addrs += addrsofif;
1715 }
1716 IFNET_RUNLOCK();
1717
1718 return (addrs);
1719 }
1720
1721 static int
1722 ni6_store_addrs(ni6, nni6, ifp0, resid)
1723 struct icmp6_nodeinfo *ni6, *nni6;
1724 struct ifnet *ifp0;
1725 int resid;
1726 {
1727 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet);
1728 struct in6_ifaddr *ifa6;
1729 struct ifaddr *ifa;
1730 struct ifnet *ifp_dep = NULL;
1731 int copied = 0, allow_deprecated = 0;
1732 u_char *cp = (u_char *)(nni6 + 1);
1733 int niflags = ni6->ni_flags;
1734 u_int32_t ltime;
1735
1736 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL))
1737 return (0); /* needless to copy */
1738
1739 IFNET_RLOCK();
1740 again:
1741
1742 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) {
1743 for (ifa = ifp->if_addrlist.tqh_first; ifa;
1744 ifa = ifa->ifa_list.tqe_next) {
1745 if (ifa->ifa_addr->sa_family != AF_INET6)
1746 continue;
1747 ifa6 = (struct in6_ifaddr *)ifa;
1748
1749 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 &&
1750 allow_deprecated == 0) {
1751 /*
1752 * prefererred address should be put before
1753 * deprecated addresses.
1754 */
1755
1756 /* record the interface for later search */
1757 if (ifp_dep == NULL)
1758 ifp_dep = ifp;
1759
1760 continue;
1761 } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 &&
1762 allow_deprecated != 0)
1763 continue; /* we now collect deprecated addrs */
1764
1765 /* What do we have to do about ::1? */
1766 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
1767 case IPV6_ADDR_SCOPE_LINKLOCAL:
1768 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
1769 continue;
1770 break;
1771 case IPV6_ADDR_SCOPE_SITELOCAL:
1772 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
1773 continue;
1774 break;
1775 case IPV6_ADDR_SCOPE_GLOBAL:
1776 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
1777 continue;
1778 break;
1779 default:
1780 continue;
1781 }
1782
1783 /*
1784 * check if anycast is okay.
1785 * XXX: just experimental. not in the spec.
1786 */
1787 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 &&
1788 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0)
1789 continue;
1790 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
1791 (icmp6_nodeinfo & 4) == 0) {
1792 continue;
1793 }
1794
1795 /* now we can copy the address */
1796 if (resid < sizeof(struct in6_addr) +
1797 sizeof(u_int32_t)) {
1798 /*
1799 * We give up much more copy.
1800 * Set the truncate flag and return.
1801 */
1802 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE;
1803 IFNET_RUNLOCK();
1804 return (copied);
1805 }
1806
1807 /*
1808 * Set the TTL of the address.
1809 * The TTL value should be one of the following
1810 * according to the specification:
1811 *
1812 * 1. The remaining lifetime of a DHCP lease on the
1813 * address, or
1814 * 2. The remaining Valid Lifetime of a prefix from
1815 * which the address was derived through Stateless
1816 * Autoconfiguration.
1817 *
1818 * Note that we currently do not support stateful
1819 * address configuration by DHCPv6, so the former
1820 * case can't happen.
1821 */
1822 if (ifa6->ia6_lifetime.ia6t_expire == 0)
1823 ltime = ND6_INFINITE_LIFETIME;
1824 else {
1825 if (ifa6->ia6_lifetime.ia6t_expire >
1826 time_second)
1827 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second);
1828 else
1829 ltime = 0;
1830 }
1831
1832 bcopy(<ime, cp, sizeof(u_int32_t));
1833 cp += sizeof(u_int32_t);
1834
1835 /* copy the address itself */
1836 bcopy(&ifa6->ia_addr.sin6_addr, cp,
1837 sizeof(struct in6_addr));
1838 in6_clearscope((struct in6_addr *)cp); /* XXX */
1839 cp += sizeof(struct in6_addr);
1840
1841 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t));
1842 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t));
1843 }
1844 if (ifp0) /* we need search only on the specified IF */
1845 break;
1846 }
1847
1848 if (allow_deprecated == 0 && ifp_dep != NULL) {
1849 ifp = ifp_dep;
1850 allow_deprecated = 1;
1851
1852 goto again;
1853 }
1854
1855 IFNET_RUNLOCK();
1856
1857 return (copied);
1858 }
1859
1860 /*
1861 * XXX almost dup'ed code with rip6_input.
1862 */
1863 static int
1864 icmp6_rip6_input(mp, off)
1865 struct mbuf **mp;
1866 int off;
1867 {
1868 struct mbuf *m = *mp;
1869 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1870 struct in6pcb *in6p;
1871 struct in6pcb *last = NULL;
1872 struct sockaddr_in6 fromsa;
1873 struct icmp6_hdr *icmp6;
1874 struct mbuf *opts = NULL;
1875
1876 #ifndef PULLDOWN_TEST
1877 /* this is assumed to be safe. */
1878 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
1879 #else
1880 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
1881 if (icmp6 == NULL) {
1882 /* m is already reclaimed */
1883 return (IPPROTO_DONE);
1884 }
1885 #endif
1886
1887 bzero(&fromsa, sizeof(fromsa));
1888 fromsa.sin6_len = sizeof(struct sockaddr_in6);
1889 fromsa.sin6_family = AF_INET6;
1890 /* KAME hack: recover scopeid */
1891 (void)in6_recoverscope(&fromsa, &ip6->ip6_src, m->m_pkthdr.rcvif);
1892
1893 INP_INFO_RLOCK(&ripcbinfo);
1894 LIST_FOREACH(in6p, &ripcb, inp_list) {
1895 INP_LOCK(in6p);
1896 if ((in6p->inp_vflag & INP_IPV6) == 0) {
1897 docontinue:
1898 INP_UNLOCK(in6p);
1899 continue;
1900 }
1901 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6)
1902 goto docontinue;
1903 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) &&
1904 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst))
1905 goto docontinue;
1906 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) &&
1907 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src))
1908 goto docontinue;
1909 if (in6p->in6p_icmp6filt
1910 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type,
1911 in6p->in6p_icmp6filt))
1912 goto docontinue;
1913 if (last) {
1914 struct mbuf *n = NULL;
1915
1916 /*
1917 * Recent network drivers tend to allocate a single
1918 * mbuf cluster, rather than to make a couple of
1919 * mbufs without clusters. Also, since the IPv6 code
1920 * path tries to avoid m_pullup(), it is highly
1921 * probable that we still have an mbuf cluster here
1922 * even though the necessary length can be stored in an
1923 * mbuf's internal buffer.
1924 * Meanwhile, the default size of the receive socket
1925 * buffer for raw sockets is not so large. This means
1926 * the possibility of packet loss is relatively higher
1927 * than before. To avoid this scenario, we copy the
1928 * received data to a separate mbuf that does not use
1929 * a cluster, if possible.
1930 * XXX: it is better to copy the data after stripping
1931 * intermediate headers.
1932 */
1933 if ((m->m_flags & M_EXT) && m->m_next == NULL &&
1934 m->m_len <= MHLEN) {
1935 MGET(n, M_DONTWAIT, m->m_type);
1936 if (n != NULL) {
1937 if (m_dup_pkthdr(n, m, M_NOWAIT)) {
1938 bcopy(m->m_data, n->m_data,
1939 m->m_len);
1940 n->m_len = m->m_len;
1941 } else {
1942 m_free(n);
1943 n = NULL;
1944 }
1945 }
1946 }
1947 if (n != NULL ||
1948 (n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
1949 if (last->in6p_flags & IN6P_CONTROLOPTS)
1950 ip6_savecontrol(last, n, &opts);
1951 /* strip intermediate headers */
1952 m_adj(n, off);
1953 if (sbappendaddr(&last->in6p_socket->so_rcv,
1954 (struct sockaddr *)&fromsa, n, opts)
1955 == 0) {
1956 /* should notify about lost packet */
1957 m_freem(n);
1958 if (opts) {
1959 m_freem(opts);
1960 }
1961 } else
1962 sorwakeup(last->in6p_socket);
1963 opts = NULL;
1964 }
1965 INP_UNLOCK(last);
1966 }
1967 last = in6p;
1968 }
1969 if (last) {
1970 if (last->in6p_flags & IN6P_CONTROLOPTS)
1971 ip6_savecontrol(last, m, &opts);
1972 /* strip intermediate headers */
1973 m_adj(m, off);
1974
1975 /* avoid using mbuf clusters if possible (see above) */
1976 if ((m->m_flags & M_EXT) && m->m_next == NULL &&
1977 m->m_len <= MHLEN) {
1978 struct mbuf *n;
1979
1980 MGET(n, M_DONTWAIT, m->m_type);
1981 if (n != NULL) {
1982 if (m_dup_pkthdr(n, m, M_NOWAIT)) {
1983 bcopy(m->m_data, n->m_data, m->m_len);
1984 n->m_len = m->m_len;
1985
1986 m_freem(m);
1987 m = n;
1988 } else {
1989 m_freem(n);
1990 n = NULL;
1991 }
1992 }
1993 }
1994 if (sbappendaddr(&last->in6p_socket->so_rcv,
1995 (struct sockaddr *)&fromsa, m, opts) == 0) {
1996 m_freem(m);
1997 if (opts)
1998 m_freem(opts);
1999 } else
2000 sorwakeup(last->in6p_socket);
2001 INP_UNLOCK(last);
2002 } else {
2003 m_freem(m);
2004 ip6stat.ip6s_delivered--;
2005 }
2006 INP_INFO_RUNLOCK(&ripcbinfo);
2007 return IPPROTO_DONE;
2008 }
2009
2010 /*
2011 * Reflect the ip6 packet back to the source.
2012 * OFF points to the icmp6 header, counted from the top of the mbuf.
2013 */
2014 void
2015 icmp6_reflect(m, off)
2016 struct mbuf *m;
2017 size_t off;
2018 {
2019 struct ip6_hdr *ip6;
2020 struct icmp6_hdr *icmp6;
2021 struct in6_ifaddr *ia;
2022 struct in6_addr t, *src = 0;
2023 int plen;
2024 int type, code;
2025 struct ifnet *outif = NULL;
2026 struct sockaddr_in6 sa6_src, sa6_dst;
2027 #ifdef COMPAT_RFC1885
2028 int mtu = IPV6_MMTU;
2029 struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst;
2030 #endif
2031
2032 /* too short to reflect */
2033 if (off < sizeof(struct ip6_hdr)) {
2034 nd6log((LOG_DEBUG,
2035 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n",
2036 (u_long)off, (u_long)sizeof(struct ip6_hdr),
2037 __FILE__, __LINE__));
2038 goto bad;
2039 }
2040
2041 /*
2042 * If there are extra headers between IPv6 and ICMPv6, strip
2043 * off that header first.
2044 */
2045 #ifdef DIAGNOSTIC
2046 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN)
2047 panic("assumption failed in icmp6_reflect");
2048 #endif
2049 if (off > sizeof(struct ip6_hdr)) {
2050 size_t l;
2051 struct ip6_hdr nip6;
2052
2053 l = off - sizeof(struct ip6_hdr);
2054 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6);
2055 m_adj(m, l);
2056 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
2057 if (m->m_len < l) {
2058 if ((m = m_pullup(m, l)) == NULL)
2059 return;
2060 }
2061 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6));
2062 } else /* off == sizeof(struct ip6_hdr) */ {
2063 size_t l;
2064 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
2065 if (m->m_len < l) {
2066 if ((m = m_pullup(m, l)) == NULL)
2067 return;
2068 }
2069 }
2070 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr);
2071 ip6 = mtod(m, struct ip6_hdr *);
2072 ip6->ip6_nxt = IPPROTO_ICMPV6;
2073 icmp6 = (struct icmp6_hdr *)(ip6 + 1);
2074 type = icmp6->icmp6_type; /* keep type for statistics */
2075 code = icmp6->icmp6_code; /* ditto. */
2076
2077 t = ip6->ip6_dst;
2078 /*
2079 * ip6_input() drops a packet if its src is multicast.
2080 * So, the src is never multicast.
2081 */
2082 ip6->ip6_dst = ip6->ip6_src;
2083
2084 /*
2085 * XXX: make sure to embed scope zone information, using
2086 * already embedded IDs or the received interface (if any).
2087 * Note that rcvif may be NULL.
2088 * TODO: scoped routing case (XXX).
2089 */
2090 bzero(&sa6_src, sizeof(sa6_src));
2091 sa6_src.sin6_family = AF_INET6;
2092 sa6_src.sin6_len = sizeof(sa6_src);
2093 sa6_src.sin6_addr = ip6->ip6_dst;
2094 in6_recoverscope(&sa6_src, &ip6->ip6_dst, m->m_pkthdr.rcvif);
2095 if (in6_embedscope(&ip6->ip6_dst, &sa6_src, NULL, NULL))
2096 goto bad;
2097
2098 bzero(&sa6_dst, sizeof(sa6_dst));
2099 sa6_dst.sin6_family = AF_INET6;
2100 sa6_dst.sin6_len = sizeof(sa6_dst);
2101 sa6_dst.sin6_addr = t;
2102 in6_recoverscope(&sa6_dst, &t, m->m_pkthdr.rcvif);
2103 if (in6_embedscope(&t, &sa6_dst, NULL, NULL))
2104 goto bad;
2105
2106 #ifdef COMPAT_RFC1885
2107 /*
2108 * xxx guess MTU
2109 * RFC 1885 requires that echo reply should be truncated if it
2110 * does not fit in with (return) path MTU, but the description was
2111 * removed in the new spec.
2112 */
2113 if (icmp6_reflect_rt.ro_rt == 0 ||
2114 ! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) {
2115 if (icmp6_reflect_rt.ro_rt) {
2116 RTFREE(icmp6_reflect_rt.ro_rt);
2117 icmp6_reflect_rt.ro_rt = 0;
2118 }
2119 bzero(sin6, sizeof(*sin6));
2120 sin6->sin6_family = PF_INET6;
2121 sin6->sin6_len = sizeof(struct sockaddr_in6);
2122 sin6->sin6_addr = ip6->ip6_dst;
2123
2124 rtalloc((struct route *)&icmp6_reflect_rt.ro_rt);
2125 }
2126
2127 if (icmp6_reflect_rt.ro_rt == 0)
2128 goto bad;
2129
2130 if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST)
2131 && mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu)
2132 mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu;
2133
2134 if (mtu < m->m_pkthdr.len) {
2135 plen -= (m->m_pkthdr.len - mtu);
2136 m_adj(m, mtu - m->m_pkthdr.len);
2137 }
2138 #endif
2139 /*
2140 * If the incoming packet was addressed directly to us (i.e. unicast),
2141 * use dst as the src for the reply.
2142 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible
2143 * (for example) when we encounter an error while forwarding procedure
2144 * destined to a duplicated address of ours.
2145 */
2146 for (ia = in6_ifaddr; ia; ia = ia->ia_next)
2147 if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) &&
2148 (ia->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) {
2149 src = &t;
2150 break;
2151 }
2152 if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) {
2153 /*
2154 * This is the case if the dst is our link-local address
2155 * and the sender is also ourselves.
2156 */
2157 src = &t;
2158 }
2159
2160 if (src == 0) {
2161 int e;
2162 struct route_in6 ro;
2163
2164 /*
2165 * This case matches to multicasts, our anycast, or unicasts
2166 * that we do not own. Select a source address based on the
2167 * source address of the erroneous packet.
2168 */
2169 bzero(&ro, sizeof(ro));
2170 src = in6_selectsrc(&sa6_src, NULL, NULL, &ro, NULL, &e);
2171 if (ro.ro_rt)
2172 RTFREE(ro.ro_rt); /* XXX: we could use this */
2173 if (src == NULL) {
2174 nd6log((LOG_DEBUG,
2175 "icmp6_reflect: source can't be determined: "
2176 "dst=%s, error=%d\n",
2177 ip6_sprintf(&sa6_src.sin6_addr), e));
2178 goto bad;
2179 }
2180 }
2181
2182 ip6->ip6_src = *src;
2183
2184 ip6->ip6_flow = 0;
2185 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
2186 ip6->ip6_vfc |= IPV6_VERSION;
2187 ip6->ip6_nxt = IPPROTO_ICMPV6;
2188 if (outif)
2189 ip6->ip6_hlim = ND_IFINFO(outif)->chlim;
2190 else if (m->m_pkthdr.rcvif) {
2191 /* XXX: This may not be the outgoing interface */
2192 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim;
2193 } else
2194 ip6->ip6_hlim = ip6_defhlim;
2195
2196 icmp6->icmp6_cksum = 0;
2197 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6,
2198 sizeof(struct ip6_hdr), plen);
2199
2200 /*
2201 * XXX option handling
2202 */
2203
2204 m->m_flags &= ~(M_BCAST|M_MCAST);
2205
2206 #ifdef COMPAT_RFC1885
2207 ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif, NULL);
2208 #else
2209 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
2210 #endif
2211 if (outif)
2212 icmp6_ifoutstat_inc(outif, type, code);
2213
2214 return;
2215
2216 bad:
2217 m_freem(m);
2218 return;
2219 }
2220
2221 void
2222 icmp6_fasttimo()
2223 {
2224
2225 mld6_fasttimeo();
2226 }
2227
2228 static const char *
2229 icmp6_redirect_diag(src6, dst6, tgt6)
2230 struct in6_addr *src6;
2231 struct in6_addr *dst6;
2232 struct in6_addr *tgt6;
2233 {
2234 static char buf[1024];
2235 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)",
2236 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6));
2237 return buf;
2238 }
2239
2240 void
2241 icmp6_redirect_input(m, off)
2242 struct mbuf *m;
2243 int off;
2244 {
2245 struct ifnet *ifp = m->m_pkthdr.rcvif;
2246 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
2247 struct nd_redirect *nd_rd;
2248 int icmp6len = ntohs(ip6->ip6_plen);
2249 char *lladdr = NULL;
2250 int lladdrlen = 0;
2251 u_char *redirhdr = NULL;
2252 int redirhdrlen = 0;
2253 struct rtentry *rt = NULL;
2254 int is_router;
2255 int is_onlink;
2256 struct in6_addr src6 = ip6->ip6_src;
2257 struct in6_addr redtgt6;
2258 struct in6_addr reddst6;
2259 union nd_opts ndopts;
2260
2261 if (!m || !ifp)
2262 return;
2263
2264 /* XXX if we are router, we don't update route by icmp6 redirect */
2265 if (ip6_forwarding)
2266 goto freeit;
2267 if (!icmp6_rediraccept)
2268 goto freeit;
2269
2270 #ifndef PULLDOWN_TEST
2271 IP6_EXTHDR_CHECK(m, off, icmp6len,);
2272 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off);
2273 #else
2274 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len);
2275 if (nd_rd == NULL) {
2276 icmp6stat.icp6s_tooshort++;
2277 return;
2278 }
2279 #endif
2280 redtgt6 = nd_rd->nd_rd_target;
2281 reddst6 = nd_rd->nd_rd_dst;
2282
2283 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
2284 redtgt6.s6_addr16[1] = htons(ifp->if_index);
2285 if (IN6_IS_ADDR_LINKLOCAL(&reddst6))
2286 reddst6.s6_addr16[1] = htons(ifp->if_index);
2287
2288 /* validation */
2289 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) {
2290 nd6log((LOG_ERR,
2291 "ICMP6 redirect sent from %s rejected; "
2292 "must be from linklocal\n",
2293 ip6_sprintf(&src6)));
2294 goto bad;
2295 }
2296 if (ip6->ip6_hlim != 255) {
2297 nd6log((LOG_ERR,
2298 "ICMP6 redirect sent from %s rejected; "
2299 "hlim=%d (must be 255)\n",
2300 ip6_sprintf(&src6), ip6->ip6_hlim));
2301 goto bad;
2302 }
2303 {
2304 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */
2305 struct sockaddr_in6 sin6;
2306 struct in6_addr *gw6;
2307
2308 bzero(&sin6, sizeof(sin6));
2309 sin6.sin6_family = AF_INET6;
2310 sin6.sin6_len = sizeof(struct sockaddr_in6);
2311 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6));
2312 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL);
2313 if (rt) {
2314 if (rt->rt_gateway == NULL ||
2315 rt->rt_gateway->sa_family != AF_INET6) {
2316 nd6log((LOG_ERR,
2317 "ICMP6 redirect rejected; no route "
2318 "with inet6 gateway found for redirect dst: %s\n",
2319 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2320 RTFREE_LOCKED(rt);
2321 goto bad;
2322 }
2323
2324 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr);
2325 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) {
2326 nd6log((LOG_ERR,
2327 "ICMP6 redirect rejected; "
2328 "not equal to gw-for-src=%s (must be same): "
2329 "%s\n",
2330 ip6_sprintf(gw6),
2331 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2332 RTFREE_LOCKED(rt);
2333 goto bad;
2334 }
2335 } else {
2336 nd6log((LOG_ERR,
2337 "ICMP6 redirect rejected; "
2338 "no route found for redirect dst: %s\n",
2339 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2340 goto bad;
2341 }
2342 RTFREE_LOCKED(rt);
2343 rt = NULL;
2344 }
2345 if (IN6_IS_ADDR_MULTICAST(&reddst6)) {
2346 nd6log((LOG_ERR,
2347 "ICMP6 redirect rejected; "
2348 "redirect dst must be unicast: %s\n",
2349 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2350 goto bad;
2351 }
2352
2353 is_router = is_onlink = 0;
2354 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
2355 is_router = 1; /* router case */
2356 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0)
2357 is_onlink = 1; /* on-link destination case */
2358 if (!is_router && !is_onlink) {
2359 nd6log((LOG_ERR,
2360 "ICMP6 redirect rejected; "
2361 "neither router case nor onlink case: %s\n",
2362 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2363 goto bad;
2364 }
2365 /* validation passed */
2366
2367 icmp6len -= sizeof(*nd_rd);
2368 nd6_option_init(nd_rd + 1, icmp6len, &ndopts);
2369 if (nd6_options(&ndopts) < 0) {
2370 nd6log((LOG_INFO, "icmp6_redirect_input: "
2371 "invalid ND option, rejected: %s\n",
2372 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2373 /* nd6_options have incremented stats */
2374 goto freeit;
2375 }
2376
2377 if (ndopts.nd_opts_tgt_lladdr) {
2378 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
2379 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
2380 }
2381
2382 if (ndopts.nd_opts_rh) {
2383 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len;
2384 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */
2385 }
2386
2387 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
2388 nd6log((LOG_INFO,
2389 "icmp6_redirect_input: lladdrlen mismatch for %s "
2390 "(if %d, icmp6 packet %d): %s\n",
2391 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2,
2392 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2393 goto bad;
2394 }
2395
2396 /* RFC 2461 8.3 */
2397 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT,
2398 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER);
2399
2400 if (!is_onlink) { /* better router case. perform rtredirect. */
2401 /* perform rtredirect */
2402 struct sockaddr_in6 sdst;
2403 struct sockaddr_in6 sgw;
2404 struct sockaddr_in6 ssrc;
2405
2406 bzero(&sdst, sizeof(sdst));
2407 bzero(&sgw, sizeof(sgw));
2408 bzero(&ssrc, sizeof(ssrc));
2409 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6;
2410 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len =
2411 sizeof(struct sockaddr_in6);
2412 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr));
2413 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
2414 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr));
2415 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw,
2416 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST,
2417 (struct sockaddr *)&ssrc);
2418 }
2419 /* finally update cached route in each socket via pfctlinput */
2420 {
2421 struct sockaddr_in6 sdst;
2422
2423 bzero(&sdst, sizeof(sdst));
2424 sdst.sin6_family = AF_INET6;
2425 sdst.sin6_len = sizeof(struct sockaddr_in6);
2426 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
2427 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst);
2428 #if defined(IPSEC) || defined(FAST_IPSEC)
2429 key_sa_routechange((struct sockaddr *)&sdst);
2430 #endif
2431 }
2432
2433 freeit:
2434 m_freem(m);
2435 return;
2436
2437 bad:
2438 icmp6stat.icp6s_badredirect++;
2439 m_freem(m);
2440 }
2441
2442 void
2443 icmp6_redirect_output(m0, rt)
2444 struct mbuf *m0;
2445 struct rtentry *rt;
2446 {
2447 struct ifnet *ifp; /* my outgoing interface */
2448 struct in6_addr *ifp_ll6;
2449 struct in6_addr *router_ll6;
2450 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */
2451 struct mbuf *m = NULL; /* newly allocated one */
2452 struct ip6_hdr *ip6; /* m as struct ip6_hdr */
2453 struct nd_redirect *nd_rd;
2454 size_t maxlen;
2455 u_char *p;
2456 struct ifnet *outif = NULL;
2457 struct sockaddr_in6 src_sa;
2458
2459 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0);
2460
2461 /* if we are not router, we don't send icmp6 redirect */
2462 if (!ip6_forwarding || ip6_accept_rtadv)
2463 goto fail;
2464
2465 /* sanity check */
2466 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp))
2467 goto fail;
2468
2469 /*
2470 * Address check:
2471 * the source address must identify a neighbor, and
2472 * the destination address must not be a multicast address
2473 * [RFC 2461, sec 8.2]
2474 */
2475 sip6 = mtod(m0, struct ip6_hdr *);
2476 bzero(&src_sa, sizeof(src_sa));
2477 src_sa.sin6_family = AF_INET6;
2478 src_sa.sin6_len = sizeof(src_sa);
2479 src_sa.sin6_addr = sip6->ip6_src;
2480 /* we don't currently use sin6_scope_id, but eventually use it */
2481 if (in6_addr2zoneid(ifp, &sip6->ip6_src, &src_sa.sin6_scope_id))
2482 goto fail;
2483 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0)
2484 goto fail;
2485 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst))
2486 goto fail; /* what should we do here? */
2487
2488 /* rate limit */
2489 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0))
2490 goto fail;
2491
2492 /*
2493 * Since we are going to append up to 1280 bytes (= IPV6_MMTU),
2494 * we almost always ask for an mbuf cluster for simplicity.
2495 * (MHLEN < IPV6_MMTU is almost always true)
2496 */
2497 #if IPV6_MMTU >= MCLBYTES
2498 # error assumption failed about IPV6_MMTU and MCLBYTES
2499 #endif
2500 MGETHDR(m, M_DONTWAIT, MT_HEADER);
2501 if (m && IPV6_MMTU >= MHLEN)
2502 MCLGET(m, M_DONTWAIT);
2503 if (!m)
2504 goto fail;
2505 m->m_pkthdr.rcvif = NULL;
2506 m->m_len = 0;
2507 maxlen = M_TRAILINGSPACE(m);
2508 maxlen = min(IPV6_MMTU, maxlen);
2509 /* just for safety */
2510 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) +
2511 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) {
2512 goto fail;
2513 }
2514
2515 {
2516 /* get ip6 linklocal address for ifp(my outgoing interface). */
2517 struct in6_ifaddr *ia;
2518 if ((ia = in6ifa_ifpforlinklocal(ifp,
2519 IN6_IFF_NOTREADY|
2520 IN6_IFF_ANYCAST)) == NULL)
2521 goto fail;
2522 ifp_ll6 = &ia->ia_addr.sin6_addr;
2523 }
2524
2525 /* get ip6 linklocal address for the router. */
2526 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) {
2527 struct sockaddr_in6 *sin6;
2528 sin6 = (struct sockaddr_in6 *)rt->rt_gateway;
2529 router_ll6 = &sin6->sin6_addr;
2530 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6))
2531 router_ll6 = (struct in6_addr *)NULL;
2532 } else
2533 router_ll6 = (struct in6_addr *)NULL;
2534
2535 /* ip6 */
2536 ip6 = mtod(m, struct ip6_hdr *);
2537 ip6->ip6_flow = 0;
2538 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
2539 ip6->ip6_vfc |= IPV6_VERSION;
2540 /* ip6->ip6_plen will be set later */
2541 ip6->ip6_nxt = IPPROTO_ICMPV6;
2542 ip6->ip6_hlim = 255;
2543 /* ip6->ip6_src must be linklocal addr for my outgoing if. */
2544 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr));
2545 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr));
2546
2547 /* ND Redirect */
2548 nd_rd = (struct nd_redirect *)(ip6 + 1);
2549 nd_rd->nd_rd_type = ND_REDIRECT;
2550 nd_rd->nd_rd_code = 0;
2551 nd_rd->nd_rd_reserved = 0;
2552 if (rt->rt_flags & RTF_GATEWAY) {
2553 /*
2554 * nd_rd->nd_rd_target must be a link-local address in
2555 * better router cases.
2556 */
2557 if (!router_ll6)
2558 goto fail;
2559 bcopy(router_ll6, &nd_rd->nd_rd_target,
2560 sizeof(nd_rd->nd_rd_target));
2561 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2562 sizeof(nd_rd->nd_rd_dst));
2563 } else {
2564 /* make sure redtgt == reddst */
2565 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target,
2566 sizeof(nd_rd->nd_rd_target));
2567 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2568 sizeof(nd_rd->nd_rd_dst));
2569 }
2570
2571 p = (u_char *)(nd_rd + 1);
2572
2573 if (!router_ll6)
2574 goto nolladdropt;
2575
2576 {
2577 /* target lladdr option */
2578 struct rtentry *rt_router = NULL;
2579 int len;
2580 struct sockaddr_dl *sdl;
2581 struct nd_opt_hdr *nd_opt;
2582 char *lladdr;
2583
2584 rt_router = nd6_lookup(router_ll6, 0, ifp);
2585 if (!rt_router)
2586 goto nolladdropt;
2587 len = sizeof(*nd_opt) + ifp->if_addrlen;
2588 len = (len + 7) & ~7; /* round by 8 */
2589 /* safety check */
2590 if (len + (p - (u_char *)ip6) > maxlen)
2591 goto nolladdropt;
2592 if (!(rt_router->rt_flags & RTF_GATEWAY) &&
2593 (rt_router->rt_flags & RTF_LLINFO) &&
2594 (rt_router->rt_gateway->sa_family == AF_LINK) &&
2595 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) &&
2596 sdl->sdl_alen) {
2597 nd_opt = (struct nd_opt_hdr *)p;
2598 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
2599 nd_opt->nd_opt_len = len >> 3;
2600 lladdr = (char *)(nd_opt + 1);
2601 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen);
2602 p += len;
2603 }
2604 }
2605 nolladdropt:;
2606
2607 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2608
2609 /* just to be safe */
2610 #ifdef M_DECRYPTED /*not openbsd*/
2611 if (m0->m_flags & M_DECRYPTED)
2612 goto noredhdropt;
2613 #endif
2614 if (p - (u_char *)ip6 > maxlen)
2615 goto noredhdropt;
2616
2617 {
2618 /* redirected header option */
2619 int len;
2620 struct nd_opt_rd_hdr *nd_opt_rh;
2621
2622 /*
2623 * compute the maximum size for icmp6 redirect header option.
2624 * XXX room for auth header?
2625 */
2626 len = maxlen - (p - (u_char *)ip6);
2627 len &= ~7;
2628
2629 /* This is just for simplicity. */
2630 if (m0->m_pkthdr.len != m0->m_len) {
2631 if (m0->m_next) {
2632 m_freem(m0->m_next);
2633 m0->m_next = NULL;
2634 }
2635 m0->m_pkthdr.len = m0->m_len;
2636 }
2637
2638 /*
2639 * Redirected header option spec (RFC2461 4.6.3) talks nothing
2640 * about padding/truncate rule for the original IP packet.
2641 * From the discussion on IPv6imp in Feb 1999,
2642 * the consensus was:
2643 * - "attach as much as possible" is the goal
2644 * - pad if not aligned (original size can be guessed by
2645 * original ip6 header)
2646 * Following code adds the padding if it is simple enough,
2647 * and truncates if not.
2648 */
2649 if (m0->m_next || m0->m_pkthdr.len != m0->m_len)
2650 panic("assumption failed in %s:%d", __FILE__,
2651 __LINE__);
2652
2653 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) {
2654 /* not enough room, truncate */
2655 m0->m_pkthdr.len = m0->m_len = len -
2656 sizeof(*nd_opt_rh);
2657 } else {
2658 /* enough room, pad or truncate */
2659 size_t extra;
2660
2661 extra = m0->m_pkthdr.len % 8;
2662 if (extra) {
2663 /* pad if easy enough, truncate if not */
2664 if (8 - extra <= M_TRAILINGSPACE(m0)) {
2665 /* pad */
2666 m0->m_len += (8 - extra);
2667 m0->m_pkthdr.len += (8 - extra);
2668 } else {
2669 /* truncate */
2670 m0->m_pkthdr.len -= extra;
2671 m0->m_len -= extra;
2672 }
2673 }
2674 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh);
2675 m0->m_pkthdr.len = m0->m_len = len -
2676 sizeof(*nd_opt_rh);
2677 }
2678
2679 nd_opt_rh = (struct nd_opt_rd_hdr *)p;
2680 bzero(nd_opt_rh, sizeof(*nd_opt_rh));
2681 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER;
2682 nd_opt_rh->nd_opt_rh_len = len >> 3;
2683 p += sizeof(*nd_opt_rh);
2684 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2685
2686 /* connect m0 to m */
2687 m_tag_delete_chain(m0, NULL);
2688 m0->m_flags &= ~M_PKTHDR;
2689 m->m_next = m0;
2690 m->m_pkthdr.len = m->m_len + m0->m_len;
2691 m0 = NULL;
2692 }
2693 noredhdropt:;
2694 if (m0) {
2695 m_freem(m0);
2696 m0 = NULL;
2697 }
2698
2699 /* XXX: clear embedded link IDs in the inner header */
2700 in6_clearscope(&sip6->ip6_src);
2701 in6_clearscope(&sip6->ip6_dst);
2702 in6_clearscope(&nd_rd->nd_rd_target);
2703 in6_clearscope(&nd_rd->nd_rd_dst);
2704
2705 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
2706
2707 nd_rd->nd_rd_cksum = 0;
2708 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6,
2709 sizeof(*ip6), ntohs(ip6->ip6_plen));
2710
2711 /* send the packet to outside... */
2712 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
2713 if (outif) {
2714 icmp6_ifstat_inc(outif, ifs6_out_msg);
2715 icmp6_ifstat_inc(outif, ifs6_out_redirect);
2716 }
2717 icmp6stat.icp6s_outhist[ND_REDIRECT]++;
2718
2719 return;
2720
2721 fail:
2722 if (m)
2723 m_freem(m);
2724 if (m0)
2725 m_freem(m0);
2726 }
2727
2728 /*
2729 * ICMPv6 socket option processing.
2730 */
2731 int
2732 icmp6_ctloutput(so, sopt)
2733 struct socket *so;
2734 struct sockopt *sopt;
2735 {
2736 int error = 0;
2737 int optlen;
2738 struct inpcb *inp = sotoinpcb(so);
2739 int level, op, optname;
2740
2741 if (sopt) {
2742 level = sopt->sopt_level;
2743 op = sopt->sopt_dir;
2744 optname = sopt->sopt_name;
2745 optlen = sopt->sopt_valsize;
2746 } else
2747 level = op = optname = optlen = 0;
2748
2749 if (level != IPPROTO_ICMPV6) {
2750 return EINVAL;
2751 }
2752
2753 switch (op) {
2754 case PRCO_SETOPT:
2755 switch (optname) {
2756 case ICMP6_FILTER:
2757 {
2758 struct icmp6_filter *p;
2759
2760 if (optlen != sizeof(*p)) {
2761 error = EMSGSIZE;
2762 break;
2763 }
2764 if (inp->in6p_icmp6filt == NULL) {
2765 error = EINVAL;
2766 break;
2767 }
2768 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen,
2769 optlen);
2770 break;
2771 }
2772
2773 default:
2774 error = ENOPROTOOPT;
2775 break;
2776 }
2777 break;
2778
2779 case PRCO_GETOPT:
2780 switch (optname) {
2781 case ICMP6_FILTER:
2782 {
2783 if (inp->in6p_icmp6filt == NULL) {
2784 error = EINVAL;
2785 break;
2786 }
2787 error = sooptcopyout(sopt, inp->in6p_icmp6filt,
2788 sizeof(struct icmp6_filter));
2789 break;
2790 }
2791
2792 default:
2793 error = ENOPROTOOPT;
2794 break;
2795 }
2796 break;
2797 }
2798
2799 return (error);
2800 }
2801
2802 /*
2803 * Perform rate limit check.
2804 * Returns 0 if it is okay to send the icmp6 packet.
2805 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate
2806 * limitation.
2807 *
2808 * XXX per-destination/type check necessary?
2809 */
2810 static int
2811 icmp6_ratelimit(dst, type, code)
2812 const struct in6_addr *dst; /* not used at this moment */
2813 const int type; /* not used at this moment */
2814 const int code; /* not used at this moment */
2815 {
2816 int ret;
2817
2818 ret = 0; /* okay to send */
2819
2820 /* PPS limit */
2821 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count,
2822 icmp6errppslim)) {
2823 /* The packet is subject to rate limit */
2824 ret++;
2825 }
2826
2827 return ret;
2828 }
Cache object: 29045730c5925b87c585ed7c84fe3383
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