FreeBSD/Linux Kernel Cross Reference
sys/netinet6/icmp6.c
1 /* $FreeBSD: releng/6.3/sys/netinet6/icmp6.c 182740 2008-09-03 19:09:47Z simon $ */
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/scope6_var.h>
99 #include <netinet6/mld6_var.h>
100 #include <netinet6/nd6.h>
101
102 #ifdef IPSEC
103 #include <netinet6/ipsec.h>
104 #include <netkey/key.h>
105 #endif
106
107 #ifdef FAST_IPSEC
108 #include <netipsec/ipsec.h>
109 #include <netipsec/key.h>
110 #endif
111
112 #include <net/net_osdep.h>
113
114 extern struct domain inet6domain;
115
116 struct icmp6stat icmp6stat;
117
118 extern struct inpcbinfo ripcbinfo;
119 extern struct inpcbhead ripcb;
120 extern int icmp6errppslim;
121 static int icmp6errpps_count = 0;
122 static struct timeval icmp6errppslim_last;
123 extern int icmp6_nodeinfo;
124
125 static void icmp6_errcount __P((struct icmp6errstat *, int, int));
126 static int icmp6_rip6_input __P((struct mbuf **, int));
127 static int icmp6_ratelimit __P((const struct in6_addr *, const int, const int));
128 static const char *icmp6_redirect_diag __P((struct in6_addr *,
129 struct in6_addr *, struct in6_addr *));
130 static struct mbuf *ni6_input __P((struct mbuf *, int));
131 static struct mbuf *ni6_nametodns __P((const char *, int, int));
132 static int ni6_dnsmatch __P((const char *, int, const char *, int));
133 static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *,
134 struct ifnet **, struct in6_addr *));
135 static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *,
136 struct ifnet *, int));
137 static int icmp6_notify_error __P((struct mbuf **, int, int, int));
138
139
140 void
141 icmp6_init()
142 {
143 mld6_init();
144 }
145
146 static void
147 icmp6_errcount(stat, type, code)
148 struct icmp6errstat *stat;
149 int type, code;
150 {
151 switch (type) {
152 case ICMP6_DST_UNREACH:
153 switch (code) {
154 case ICMP6_DST_UNREACH_NOROUTE:
155 stat->icp6errs_dst_unreach_noroute++;
156 return;
157 case ICMP6_DST_UNREACH_ADMIN:
158 stat->icp6errs_dst_unreach_admin++;
159 return;
160 case ICMP6_DST_UNREACH_BEYONDSCOPE:
161 stat->icp6errs_dst_unreach_beyondscope++;
162 return;
163 case ICMP6_DST_UNREACH_ADDR:
164 stat->icp6errs_dst_unreach_addr++;
165 return;
166 case ICMP6_DST_UNREACH_NOPORT:
167 stat->icp6errs_dst_unreach_noport++;
168 return;
169 }
170 break;
171 case ICMP6_PACKET_TOO_BIG:
172 stat->icp6errs_packet_too_big++;
173 return;
174 case ICMP6_TIME_EXCEEDED:
175 switch (code) {
176 case ICMP6_TIME_EXCEED_TRANSIT:
177 stat->icp6errs_time_exceed_transit++;
178 return;
179 case ICMP6_TIME_EXCEED_REASSEMBLY:
180 stat->icp6errs_time_exceed_reassembly++;
181 return;
182 }
183 break;
184 case ICMP6_PARAM_PROB:
185 switch (code) {
186 case ICMP6_PARAMPROB_HEADER:
187 stat->icp6errs_paramprob_header++;
188 return;
189 case ICMP6_PARAMPROB_NEXTHEADER:
190 stat->icp6errs_paramprob_nextheader++;
191 return;
192 case ICMP6_PARAMPROB_OPTION:
193 stat->icp6errs_paramprob_option++;
194 return;
195 }
196 break;
197 case ND_REDIRECT:
198 stat->icp6errs_redirect++;
199 return;
200 }
201 stat->icp6errs_unknown++;
202 }
203
204 /*
205 * A wrapper function for icmp6_error() necessary when the erroneous packet
206 * may not contain enough scope zone information.
207 */
208 void
209 icmp6_error2(m, type, code, param, ifp)
210 struct mbuf *m;
211 int type, code, param;
212 struct ifnet *ifp;
213 {
214 struct ip6_hdr *ip6;
215
216 if (ifp == NULL)
217 return;
218
219 #ifndef PULLDOWN_TEST
220 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), );
221 #else
222 if (m->m_len < sizeof(struct ip6_hdr)) {
223 m = m_pullup(m, sizeof(struct ip6_hdr));
224 if (m == NULL)
225 return;
226 }
227 #endif
228
229 ip6 = mtod(m, struct ip6_hdr *);
230
231 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0)
232 return;
233 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0)
234 return;
235
236 icmp6_error(m, type, code, param);
237 }
238
239 /*
240 * Generate an error packet of type error in response to bad IP6 packet.
241 */
242 void
243 icmp6_error(m, type, code, param)
244 struct mbuf *m;
245 int type, code, param;
246 {
247 struct ip6_hdr *oip6, *nip6;
248 struct icmp6_hdr *icmp6;
249 u_int preplen;
250 int off;
251 int nxt;
252
253 icmp6stat.icp6s_error++;
254
255 /* count per-type-code statistics */
256 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code);
257
258 #ifdef M_DECRYPTED /*not openbsd*/
259 if (m->m_flags & M_DECRYPTED) {
260 icmp6stat.icp6s_canterror++;
261 goto freeit;
262 }
263 #endif
264
265 #ifndef PULLDOWN_TEST
266 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), );
267 #else
268 if (m->m_len < sizeof(struct ip6_hdr)) {
269 m = m_pullup(m, sizeof(struct ip6_hdr));
270 if (m == NULL)
271 return;
272 }
273 #endif
274 oip6 = mtod(m, struct ip6_hdr *);
275
276 /*
277 * If the destination address of the erroneous packet is a multicast
278 * address, or the packet was sent using link-layer multicast,
279 * we should basically suppress sending an error (RFC 2463, Section
280 * 2.4).
281 * We have two exceptions (the item e.2 in that section):
282 * - the Pakcet Too Big message can be sent for path MTU discovery.
283 * - the Parameter Problem Message that can be allowed an icmp6 error
284 * in the option type field. This check has been done in
285 * ip6_unknown_opt(), so we can just check the type and code.
286 */
287 if ((m->m_flags & (M_BCAST|M_MCAST) ||
288 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) &&
289 (type != ICMP6_PACKET_TOO_BIG &&
290 (type != ICMP6_PARAM_PROB ||
291 code != ICMP6_PARAMPROB_OPTION)))
292 goto freeit;
293
294 /*
295 * RFC 2463, 2.4 (e.5): source address check.
296 * XXX: the case of anycast source?
297 */
298 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) ||
299 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src))
300 goto freeit;
301
302 /*
303 * If we are about to send ICMPv6 against ICMPv6 error/redirect,
304 * don't do it.
305 */
306 nxt = -1;
307 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
308 if (off >= 0 && nxt == IPPROTO_ICMPV6) {
309 struct icmp6_hdr *icp;
310
311 #ifndef PULLDOWN_TEST
312 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), );
313 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
314 #else
315 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off,
316 sizeof(*icp));
317 if (icp == NULL) {
318 icmp6stat.icp6s_tooshort++;
319 return;
320 }
321 #endif
322 if (icp->icmp6_type < ICMP6_ECHO_REQUEST ||
323 icp->icmp6_type == ND_REDIRECT) {
324 /*
325 * ICMPv6 error
326 * Special case: for redirect (which is
327 * informational) we must not send icmp6 error.
328 */
329 icmp6stat.icp6s_canterror++;
330 goto freeit;
331 } else {
332 /* ICMPv6 informational - send the error */
333 }
334 } else {
335 /* non-ICMPv6 - send the error */
336 }
337
338 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */
339
340 /* Finally, do rate limitation check. */
341 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) {
342 icmp6stat.icp6s_toofreq++;
343 goto freeit;
344 }
345
346 /*
347 * OK, ICMP6 can be generated.
348 */
349
350 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN)
351 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len);
352
353 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
354 M_PREPEND(m, preplen, M_DONTWAIT);
355 if (m && m->m_len < preplen)
356 m = m_pullup(m, preplen);
357 if (m == NULL) {
358 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__));
359 return;
360 }
361
362 nip6 = mtod(m, struct ip6_hdr *);
363 nip6->ip6_src = oip6->ip6_src;
364 nip6->ip6_dst = oip6->ip6_dst;
365
366 in6_clearscope(&oip6->ip6_src);
367 in6_clearscope(&oip6->ip6_dst);
368
369 icmp6 = (struct icmp6_hdr *)(nip6 + 1);
370 icmp6->icmp6_type = type;
371 icmp6->icmp6_code = code;
372 icmp6->icmp6_pptr = htonl((u_int32_t)param);
373
374 /*
375 * icmp6_reflect() is designed to be in the input path.
376 * icmp6_error() can be called from both input and output path,
377 * and if we are in output path rcvif could contain bogus value.
378 * clear m->m_pkthdr.rcvif for safety, we should have enough scope
379 * information in ip header (nip6).
380 */
381 m->m_pkthdr.rcvif = NULL;
382
383 icmp6stat.icp6s_outhist[type]++;
384 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */
385
386 return;
387
388 freeit:
389 /*
390 * If we can't tell whether or not we can generate ICMP6, free it.
391 */
392 m_freem(m);
393 }
394
395 /*
396 * Process a received ICMP6 message.
397 */
398 int
399 icmp6_input(mp, offp, proto)
400 struct mbuf **mp;
401 int *offp, proto;
402 {
403 struct mbuf *m = *mp, *n;
404 struct ip6_hdr *ip6, *nip6;
405 struct icmp6_hdr *icmp6, *nicmp6;
406 int off = *offp;
407 int icmp6len = m->m_pkthdr.len - *offp;
408 int code, sum, noff;
409
410 #ifndef PULLDOWN_TEST
411 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE);
412 /* m might change if M_LOOP. So, call mtod after this */
413 #endif
414
415 /*
416 * Locate icmp6 structure in mbuf, and check
417 * that not corrupted and of at least minimum length
418 */
419
420 ip6 = mtod(m, struct ip6_hdr *);
421 if (icmp6len < sizeof(struct icmp6_hdr)) {
422 icmp6stat.icp6s_tooshort++;
423 goto freeit;
424 }
425
426 /*
427 * calculate the checksum
428 */
429 #ifndef PULLDOWN_TEST
430 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
431 #else
432 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
433 if (icmp6 == NULL) {
434 icmp6stat.icp6s_tooshort++;
435 return IPPROTO_DONE;
436 }
437 #endif
438 code = icmp6->icmp6_code;
439
440 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) {
441 nd6log((LOG_ERR,
442 "ICMP6 checksum error(%d|%x) %s\n",
443 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src)));
444 icmp6stat.icp6s_checksum++;
445 goto freeit;
446 }
447
448 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) {
449 /*
450 * Deliver very specific ICMP6 type only.
451 * This is important to deliver TOOBIG. Otherwise PMTUD
452 * will not work.
453 */
454 switch (icmp6->icmp6_type) {
455 case ICMP6_DST_UNREACH:
456 case ICMP6_PACKET_TOO_BIG:
457 case ICMP6_TIME_EXCEEDED:
458 break;
459 default:
460 goto freeit;
461 }
462 }
463
464 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++;
465 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg);
466 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK)
467 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error);
468
469 switch (icmp6->icmp6_type) {
470 case ICMP6_DST_UNREACH:
471 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach);
472 switch (code) {
473 case ICMP6_DST_UNREACH_NOROUTE:
474 code = PRC_UNREACH_NET;
475 break;
476 case ICMP6_DST_UNREACH_ADMIN:
477 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib);
478 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */
479 break;
480 case ICMP6_DST_UNREACH_ADDR:
481 code = PRC_HOSTDEAD;
482 break;
483 case ICMP6_DST_UNREACH_BEYONDSCOPE:
484 /* I mean "source address was incorrect." */
485 code = PRC_PARAMPROB;
486 break;
487 case ICMP6_DST_UNREACH_NOPORT:
488 code = PRC_UNREACH_PORT;
489 break;
490 default:
491 goto badcode;
492 }
493 goto deliver;
494 break;
495
496 case ICMP6_PACKET_TOO_BIG:
497 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig);
498
499 /* validation is made in icmp6_mtudisc_update */
500
501 code = PRC_MSGSIZE;
502
503 /*
504 * Updating the path MTU will be done after examining
505 * intermediate extension headers.
506 */
507 goto deliver;
508 break;
509
510 case ICMP6_TIME_EXCEEDED:
511 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed);
512 switch (code) {
513 case ICMP6_TIME_EXCEED_TRANSIT:
514 code = PRC_TIMXCEED_INTRANS;
515 break;
516 case ICMP6_TIME_EXCEED_REASSEMBLY:
517 code = PRC_TIMXCEED_REASS;
518 break;
519 default:
520 goto badcode;
521 }
522 goto deliver;
523 break;
524
525 case ICMP6_PARAM_PROB:
526 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob);
527 switch (code) {
528 case ICMP6_PARAMPROB_NEXTHEADER:
529 code = PRC_UNREACH_PROTOCOL;
530 break;
531 case ICMP6_PARAMPROB_HEADER:
532 case ICMP6_PARAMPROB_OPTION:
533 code = PRC_PARAMPROB;
534 break;
535 default:
536 goto badcode;
537 }
538 goto deliver;
539 break;
540
541 case ICMP6_ECHO_REQUEST:
542 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo);
543 if (code != 0)
544 goto badcode;
545 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) {
546 /* Give up remote */
547 break;
548 }
549 if ((n->m_flags & M_EXT) != 0
550 || n->m_len < off + sizeof(struct icmp6_hdr)) {
551 struct mbuf *n0 = n;
552 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6);
553 int n0len;
554
555 MGETHDR(n, M_DONTWAIT, n0->m_type);
556 n0len = n0->m_pkthdr.len; /* save for use below */
557 if (n)
558 M_MOVE_PKTHDR(n, n0);
559 if (n && maxlen >= MHLEN) {
560 MCLGET(n, M_DONTWAIT);
561 if ((n->m_flags & M_EXT) == 0) {
562 m_free(n);
563 n = NULL;
564 }
565 }
566 if (n == NULL) {
567 /* Give up remote */
568 m_freem(n0);
569 break;
570 }
571 /*
572 * Copy IPv6 and ICMPv6 only.
573 */
574 nip6 = mtod(n, struct ip6_hdr *);
575 bcopy(ip6, nip6, sizeof(struct ip6_hdr));
576 nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
577 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
578 noff = sizeof(struct ip6_hdr);
579 /* new mbuf contains only ipv6+icmpv6 headers */
580 n->m_len = noff + sizeof(struct icmp6_hdr);
581 /*
582 * Adjust mbuf. ip6_plen will be adjusted in
583 * ip6_output().
584 */
585 m_adj(n0, off + sizeof(struct icmp6_hdr));
586 /* recalculate complete packet size */
587 n->m_pkthdr.len = n0len + (noff - off);
588 n->m_next = n0;
589 } else {
590 nip6 = mtod(n, struct ip6_hdr *);
591 IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off,
592 sizeof(*nicmp6));
593 noff = off;
594 }
595 nicmp6->icmp6_type = ICMP6_ECHO_REPLY;
596 nicmp6->icmp6_code = 0;
597 if (n) {
598 icmp6stat.icp6s_reflect++;
599 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++;
600 icmp6_reflect(n, noff);
601 }
602 break;
603
604 case ICMP6_ECHO_REPLY:
605 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply);
606 if (code != 0)
607 goto badcode;
608 break;
609
610 case MLD_LISTENER_QUERY:
611 case MLD_LISTENER_REPORT:
612 if (icmp6len < sizeof(struct mld_hdr))
613 goto badlen;
614 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */
615 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery);
616 else
617 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport);
618 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
619 /* give up local */
620 mld6_input(m, off);
621 m = NULL;
622 goto freeit;
623 }
624 mld6_input(n, off);
625 /* m stays. */
626 break;
627
628 case MLD_LISTENER_DONE:
629 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone);
630 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */
631 goto badlen;
632 break; /* nothing to be done in kernel */
633
634 case MLD_MTRACE_RESP:
635 case MLD_MTRACE:
636 /* XXX: these two are experimental. not officially defined. */
637 /* XXX: per-interface statistics? */
638 break; /* just pass it to applications */
639
640 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */
641 {
642 enum { WRU, FQDN } mode;
643
644 if (!icmp6_nodeinfo)
645 break;
646
647 if (icmp6len == sizeof(struct icmp6_hdr) + 4)
648 mode = WRU;
649 else if (icmp6len >= sizeof(struct icmp6_nodeinfo))
650 mode = FQDN;
651 else
652 goto badlen;
653
654 #define hostnamelen strlen(hostname)
655 if (mode == FQDN) {
656 #ifndef PULLDOWN_TEST
657 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo),
658 IPPROTO_DONE);
659 #endif
660 n = m_copy(m, 0, M_COPYALL);
661 if (n)
662 n = ni6_input(n, off);
663 /* XXX meaningless if n == NULL */
664 noff = sizeof(struct ip6_hdr);
665 } else {
666 u_char *p;
667 int maxlen, maxhlen;
668
669 /*
670 * XXX: this combination of flags is pointless,
671 * but should we keep this for compatibility?
672 */
673 if ((icmp6_nodeinfo & 5) != 5)
674 break;
675
676 if (code != 0)
677 goto badcode;
678 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4;
679 if (maxlen >= MCLBYTES) {
680 /* Give up remote */
681 break;
682 }
683 MGETHDR(n, M_DONTWAIT, m->m_type);
684 if (n && maxlen > MHLEN) {
685 MCLGET(n, M_DONTWAIT);
686 if ((n->m_flags & M_EXT) == 0) {
687 m_free(n);
688 n = NULL;
689 }
690 }
691 if (n && !m_dup_pkthdr(n, m, M_DONTWAIT)) {
692 /*
693 * Previous code did a blind M_COPY_PKTHDR
694 * and said "just for rcvif". If true, then
695 * we could tolerate the dup failing (due to
696 * the deep copy of the tag chain). For now
697 * be conservative and just fail.
698 */
699 m_free(n);
700 n = NULL;
701 }
702 if (n == NULL) {
703 /* Give up remote */
704 break;
705 }
706 n->m_pkthdr.rcvif = NULL;
707 n->m_len = 0;
708 maxhlen = M_TRAILINGSPACE(n) - maxlen;
709 if (maxhlen > hostnamelen)
710 maxhlen = hostnamelen;
711 /*
712 * Copy IPv6 and ICMPv6 only.
713 */
714 nip6 = mtod(n, struct ip6_hdr *);
715 bcopy(ip6, nip6, sizeof(struct ip6_hdr));
716 nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
717 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
718 p = (u_char *)(nicmp6 + 1);
719 bzero(p, 4);
720 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */
721 noff = sizeof(struct ip6_hdr);
722 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
723 sizeof(struct icmp6_hdr) + 4 + maxhlen;
724 nicmp6->icmp6_type = ICMP6_WRUREPLY;
725 nicmp6->icmp6_code = 0;
726 }
727 #undef hostnamelen
728 if (n) {
729 icmp6stat.icp6s_reflect++;
730 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++;
731 icmp6_reflect(n, noff);
732 }
733 break;
734 }
735
736 case ICMP6_WRUREPLY:
737 if (code != 0)
738 goto badcode;
739 break;
740
741 case ND_ROUTER_SOLICIT:
742 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit);
743 if (code != 0)
744 goto badcode;
745 if (icmp6len < sizeof(struct nd_router_solicit))
746 goto badlen;
747 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
748 /* give up local */
749 nd6_rs_input(m, off, icmp6len);
750 m = NULL;
751 goto freeit;
752 }
753 nd6_rs_input(n, off, icmp6len);
754 /* m stays. */
755 break;
756
757 case ND_ROUTER_ADVERT:
758 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert);
759 if (code != 0)
760 goto badcode;
761 if (icmp6len < sizeof(struct nd_router_advert))
762 goto badlen;
763 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
764 /* give up local */
765 nd6_ra_input(m, off, icmp6len);
766 m = NULL;
767 goto freeit;
768 }
769 nd6_ra_input(n, off, icmp6len);
770 /* m stays. */
771 break;
772
773 case ND_NEIGHBOR_SOLICIT:
774 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit);
775 if (code != 0)
776 goto badcode;
777 if (icmp6len < sizeof(struct nd_neighbor_solicit))
778 goto badlen;
779 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
780 /* give up local */
781 nd6_ns_input(m, off, icmp6len);
782 m = NULL;
783 goto freeit;
784 }
785 nd6_ns_input(n, off, icmp6len);
786 /* m stays. */
787 break;
788
789 case ND_NEIGHBOR_ADVERT:
790 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert);
791 if (code != 0)
792 goto badcode;
793 if (icmp6len < sizeof(struct nd_neighbor_advert))
794 goto badlen;
795 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
796 /* give up local */
797 nd6_na_input(m, off, icmp6len);
798 m = NULL;
799 goto freeit;
800 }
801 nd6_na_input(n, off, icmp6len);
802 /* m stays. */
803 break;
804
805 case ND_REDIRECT:
806 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect);
807 if (code != 0)
808 goto badcode;
809 if (icmp6len < sizeof(struct nd_redirect))
810 goto badlen;
811 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
812 /* give up local */
813 icmp6_redirect_input(m, off);
814 m = NULL;
815 goto freeit;
816 }
817 icmp6_redirect_input(n, off);
818 /* m stays. */
819 break;
820
821 case ICMP6_ROUTER_RENUMBERING:
822 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND &&
823 code != ICMP6_ROUTER_RENUMBERING_RESULT)
824 goto badcode;
825 if (icmp6len < sizeof(struct icmp6_router_renum))
826 goto badlen;
827 break;
828
829 default:
830 nd6log((LOG_DEBUG,
831 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n",
832 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src),
833 ip6_sprintf(&ip6->ip6_dst),
834 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0));
835 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) {
836 /* ICMPv6 error: MUST deliver it by spec... */
837 code = PRC_NCMDS;
838 /* deliver */
839 } else {
840 /* ICMPv6 informational: MUST not deliver */
841 break;
842 }
843 deliver:
844 if (icmp6_notify_error(&m, off, icmp6len, code)) {
845 /* In this case, m should've been freed. */
846 return (IPPROTO_DONE);
847 }
848 break;
849
850 badcode:
851 icmp6stat.icp6s_badcode++;
852 break;
853
854 badlen:
855 icmp6stat.icp6s_badlen++;
856 break;
857 }
858
859 /* deliver the packet to appropriate sockets */
860 icmp6_rip6_input(&m, *offp);
861
862 return IPPROTO_DONE;
863
864 freeit:
865 m_freem(m);
866 return IPPROTO_DONE;
867 }
868
869 static int
870 icmp6_notify_error(mp, off, icmp6len, code)
871 struct mbuf **mp;
872 int off, icmp6len, code;
873 {
874 struct mbuf *m = *mp;
875 struct icmp6_hdr *icmp6;
876 struct ip6_hdr *eip6;
877 u_int32_t notifymtu;
878 struct sockaddr_in6 icmp6src, icmp6dst;
879
880 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) {
881 icmp6stat.icp6s_tooshort++;
882 goto freeit;
883 }
884 #ifndef PULLDOWN_TEST
885 IP6_EXTHDR_CHECK(m, off,
886 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1);
887 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
888 #else
889 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
890 sizeof(*icmp6) + sizeof(struct ip6_hdr));
891 if (icmp6 == NULL) {
892 icmp6stat.icp6s_tooshort++;
893 return (-1);
894 }
895 #endif
896 eip6 = (struct ip6_hdr *)(icmp6 + 1);
897
898 /* Detect the upper level protocol */
899 {
900 void (*ctlfunc) __P((int, struct sockaddr *, void *));
901 u_int8_t nxt = eip6->ip6_nxt;
902 int eoff = off + sizeof(struct icmp6_hdr) +
903 sizeof(struct ip6_hdr);
904 struct ip6ctlparam ip6cp;
905 struct in6_addr *finaldst = NULL;
906 int icmp6type = icmp6->icmp6_type;
907 struct ip6_frag *fh;
908 struct ip6_rthdr *rth;
909 struct ip6_rthdr0 *rth0;
910 int rthlen;
911
912 while (1) { /* XXX: should avoid infinite loop explicitly? */
913 struct ip6_ext *eh;
914
915 switch (nxt) {
916 case IPPROTO_HOPOPTS:
917 case IPPROTO_DSTOPTS:
918 case IPPROTO_AH:
919 #ifndef PULLDOWN_TEST
920 IP6_EXTHDR_CHECK(m, 0,
921 eoff + sizeof(struct ip6_ext), -1);
922 eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff);
923 #else
924 IP6_EXTHDR_GET(eh, struct ip6_ext *, m,
925 eoff, sizeof(*eh));
926 if (eh == NULL) {
927 icmp6stat.icp6s_tooshort++;
928 return (-1);
929 }
930 #endif
931
932 if (nxt == IPPROTO_AH)
933 eoff += (eh->ip6e_len + 2) << 2;
934 else
935 eoff += (eh->ip6e_len + 1) << 3;
936 nxt = eh->ip6e_nxt;
937 break;
938 case IPPROTO_ROUTING:
939 /*
940 * When the erroneous packet contains a
941 * routing header, we should examine the
942 * header to determine the final destination.
943 * Otherwise, we can't properly update
944 * information that depends on the final
945 * destination (e.g. path MTU).
946 */
947 #ifndef PULLDOWN_TEST
948 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1);
949 rth = (struct ip6_rthdr *)
950 (mtod(m, caddr_t) + eoff);
951 #else
952 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m,
953 eoff, sizeof(*rth));
954 if (rth == NULL) {
955 icmp6stat.icp6s_tooshort++;
956 return (-1);
957 }
958 #endif
959 rthlen = (rth->ip6r_len + 1) << 3;
960 /*
961 * XXX: currently there is no
962 * officially defined type other
963 * than type-0.
964 * Note that if the segment left field
965 * is 0, all intermediate hops must
966 * have been passed.
967 */
968 if (rth->ip6r_segleft &&
969 rth->ip6r_type == IPV6_RTHDR_TYPE_0) {
970 int hops;
971
972 #ifndef PULLDOWN_TEST
973 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1);
974 rth0 = (struct ip6_rthdr0 *)
975 (mtod(m, caddr_t) + eoff);
976 #else
977 IP6_EXTHDR_GET(rth0,
978 struct ip6_rthdr0 *, m,
979 eoff, rthlen);
980 if (rth0 == NULL) {
981 icmp6stat.icp6s_tooshort++;
982 return (-1);
983 }
984 #endif
985 /* just ignore a bogus header */
986 if ((rth0->ip6r0_len % 2) == 0 &&
987 (hops = rth0->ip6r0_len/2))
988 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1);
989 }
990 eoff += rthlen;
991 nxt = rth->ip6r_nxt;
992 break;
993 case IPPROTO_FRAGMENT:
994 #ifndef PULLDOWN_TEST
995 IP6_EXTHDR_CHECK(m, 0, eoff +
996 sizeof(struct ip6_frag), -1);
997 fh = (struct ip6_frag *)(mtod(m, caddr_t) +
998 eoff);
999 #else
1000 IP6_EXTHDR_GET(fh, struct ip6_frag *, m,
1001 eoff, sizeof(*fh));
1002 if (fh == NULL) {
1003 icmp6stat.icp6s_tooshort++;
1004 return (-1);
1005 }
1006 #endif
1007 /*
1008 * Data after a fragment header is meaningless
1009 * unless it is the first fragment, but
1010 * we'll go to the notify label for path MTU
1011 * discovery.
1012 */
1013 if (fh->ip6f_offlg & IP6F_OFF_MASK)
1014 goto notify;
1015
1016 eoff += sizeof(struct ip6_frag);
1017 nxt = fh->ip6f_nxt;
1018 break;
1019 default:
1020 /*
1021 * This case includes ESP and the No Next
1022 * Header. In such cases going to the notify
1023 * label does not have any meaning
1024 * (i.e. ctlfunc will be NULL), but we go
1025 * anyway since we might have to update
1026 * path MTU information.
1027 */
1028 goto notify;
1029 }
1030 }
1031 notify:
1032 #ifndef PULLDOWN_TEST
1033 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
1034 #else
1035 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
1036 sizeof(*icmp6) + sizeof(struct ip6_hdr));
1037 if (icmp6 == NULL) {
1038 icmp6stat.icp6s_tooshort++;
1039 return (-1);
1040 }
1041 #endif
1042
1043 /*
1044 * retrieve parameters from the inner IPv6 header, and convert
1045 * them into sockaddr structures.
1046 * XXX: there is no guarantee that the source or destination
1047 * addresses of the inner packet are in the same scope as
1048 * the addresses of the icmp packet. But there is no other
1049 * way to determine the zone.
1050 */
1051 eip6 = (struct ip6_hdr *)(icmp6 + 1);
1052
1053 bzero(&icmp6dst, sizeof(icmp6dst));
1054 icmp6dst.sin6_len = sizeof(struct sockaddr_in6);
1055 icmp6dst.sin6_family = AF_INET6;
1056 if (finaldst == NULL)
1057 icmp6dst.sin6_addr = eip6->ip6_dst;
1058 else
1059 icmp6dst.sin6_addr = *finaldst;
1060 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL))
1061 goto freeit;
1062 bzero(&icmp6src, sizeof(icmp6src));
1063 icmp6src.sin6_len = sizeof(struct sockaddr_in6);
1064 icmp6src.sin6_family = AF_INET6;
1065 icmp6src.sin6_addr = eip6->ip6_src;
1066 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL))
1067 goto freeit;
1068 icmp6src.sin6_flowinfo =
1069 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK);
1070
1071 if (finaldst == NULL)
1072 finaldst = &eip6->ip6_dst;
1073 ip6cp.ip6c_m = m;
1074 ip6cp.ip6c_icmp6 = icmp6;
1075 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1);
1076 ip6cp.ip6c_off = eoff;
1077 ip6cp.ip6c_finaldst = finaldst;
1078 ip6cp.ip6c_src = &icmp6src;
1079 ip6cp.ip6c_nxt = nxt;
1080
1081 if (icmp6type == ICMP6_PACKET_TOO_BIG) {
1082 notifymtu = ntohl(icmp6->icmp6_mtu);
1083 ip6cp.ip6c_cmdarg = (void *)¬ifymtu;
1084 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/
1085 }
1086
1087 ctlfunc = (void (*) __P((int, struct sockaddr *, void *)))
1088 (inet6sw[ip6_protox[nxt]].pr_ctlinput);
1089 if (ctlfunc) {
1090 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst,
1091 &ip6cp);
1092 }
1093 }
1094 *mp = m;
1095 return (0);
1096
1097 freeit:
1098 m_freem(m);
1099 return (-1);
1100 }
1101
1102 void
1103 icmp6_mtudisc_update(ip6cp, validated)
1104 struct ip6ctlparam *ip6cp;
1105 int validated;
1106 {
1107 struct in6_addr *dst = ip6cp->ip6c_finaldst;
1108 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6;
1109 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */
1110 u_int mtu = ntohl(icmp6->icmp6_mtu);
1111 struct in_conninfo inc;
1112
1113 #if 0
1114 /*
1115 * RFC2460 section 5, last paragraph.
1116 * even though minimum link MTU for IPv6 is IPV6_MMTU,
1117 * we may see ICMPv6 too big with mtu < IPV6_MMTU
1118 * due to packet translator in the middle.
1119 * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for
1120 * special handling.
1121 */
1122 if (mtu < IPV6_MMTU)
1123 return;
1124 #endif
1125
1126 /*
1127 * we reject ICMPv6 too big with abnormally small value.
1128 * XXX what is the good definition of "abnormally small"?
1129 */
1130 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8)
1131 return;
1132
1133 if (!validated)
1134 return;
1135
1136 /*
1137 * In case the suggested mtu is less than IPV6_MMTU, we
1138 * only need to remember that it was for above mentioned
1139 * "alwaysfrag" case.
1140 * Try to be as close to the spec as possible.
1141 */
1142 if (mtu < IPV6_MMTU)
1143 mtu = IPV6_MMTU - 8;
1144
1145 bzero(&inc, sizeof(inc));
1146 inc.inc_flags = 1; /* IPv6 */
1147 inc.inc6_faddr = *dst;
1148 if (in6_setscope(&inc.inc6_faddr, m->m_pkthdr.rcvif, NULL))
1149 return;
1150
1151 if (mtu < tcp_maxmtu6(&inc)) {
1152 tcp_hc_updatemtu(&inc, mtu);
1153 icmp6stat.icp6s_pmtuchg++;
1154 }
1155 }
1156
1157 /*
1158 * Process a Node Information Query packet, based on
1159 * draft-ietf-ipngwg-icmp-name-lookups-07.
1160 *
1161 * Spec incompatibilities:
1162 * - IPv6 Subject address handling
1163 * - IPv4 Subject address handling support missing
1164 * - Proxy reply (answer even if it's not for me)
1165 * - joins NI group address at in6_ifattach() time only, does not cope
1166 * with hostname changes by sethostname(3)
1167 */
1168 #define hostnamelen strlen(hostname)
1169 static struct mbuf *
1170 ni6_input(m, off)
1171 struct mbuf *m;
1172 int off;
1173 {
1174 struct icmp6_nodeinfo *ni6, *nni6;
1175 struct mbuf *n = NULL;
1176 u_int16_t qtype;
1177 int subjlen;
1178 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
1179 struct ni_reply_fqdn *fqdn;
1180 int addrs; /* for NI_QTYPE_NODEADDR */
1181 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */
1182 struct in6_addr in6_subj; /* subject address */
1183 struct ip6_hdr *ip6;
1184 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */
1185 char *subj = NULL;
1186 struct in6_ifaddr *ia6 = NULL;
1187
1188 ip6 = mtod(m, struct ip6_hdr *);
1189 #ifndef PULLDOWN_TEST
1190 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off);
1191 #else
1192 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6));
1193 if (ni6 == NULL) {
1194 /* m is already reclaimed */
1195 return (NULL);
1196 }
1197 #endif
1198
1199 /*
1200 * Validate IPv6 source address.
1201 * The default configuration MUST be to refuse answering queries from
1202 * global-scope addresses according to RFC4602.
1203 * Notes:
1204 * - it's not very clear what "refuse" means; this implementation
1205 * simply drops it.
1206 * - it's not very easy to identify global-scope (unicast) addresses
1207 * since there are many prefixes for them. It should be safer
1208 * and in practice sufficient to check "all" but loopback and
1209 * link-local (note that site-local unicast was deprecated and
1210 * ULA is defined as global scope-wise)
1211 */
1212 if ((icmp6_nodeinfo & ICMP6_NODEINFO_GLOBALOK) == 0 &&
1213 !IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) &&
1214 !IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src))
1215 goto bad;
1216
1217 /*
1218 * Validate IPv6 destination address.
1219 *
1220 * The Responder must discard the Query without further processing
1221 * unless it is one of the Responder's unicast or anycast addresses, or
1222 * a link-local scope multicast address which the Responder has joined.
1223 * [RFC4602, Section 5.]
1224 */
1225 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
1226 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst))
1227 goto bad;
1228 /* else it's a link-local multicast, fine */
1229 } else { /* unicast or anycast */
1230 if ((ia6 = ip6_getdstifaddr(m)) == NULL)
1231 goto bad; /* XXX impossible */
1232
1233 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) &&
1234 !(icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK)) {
1235 nd6log((LOG_DEBUG, "ni6_input: ignore node info to "
1236 "a temporary address in %s:%d",
1237 __FILE__, __LINE__));
1238 goto bad;
1239 }
1240 }
1241
1242 /* validate query Subject field. */
1243 qtype = ntohs(ni6->ni_qtype);
1244 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo);
1245 switch (qtype) {
1246 case NI_QTYPE_NOOP:
1247 case NI_QTYPE_SUPTYPES:
1248 /* 07 draft */
1249 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0)
1250 break;
1251 /* FALLTHROUGH */
1252 case NI_QTYPE_FQDN:
1253 case NI_QTYPE_NODEADDR:
1254 case NI_QTYPE_IPV4ADDR:
1255 switch (ni6->ni_code) {
1256 case ICMP6_NI_SUBJ_IPV6:
1257 #if ICMP6_NI_SUBJ_IPV6 != 0
1258 case 0:
1259 #endif
1260 /*
1261 * backward compatibility - try to accept 03 draft
1262 * format, where no Subject is present.
1263 */
1264 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 &&
1265 subjlen == 0) {
1266 oldfqdn++;
1267 break;
1268 }
1269 #if ICMP6_NI_SUBJ_IPV6 != 0
1270 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6)
1271 goto bad;
1272 #endif
1273
1274 if (subjlen != sizeof(struct in6_addr))
1275 goto bad;
1276
1277 /*
1278 * Validate Subject address.
1279 *
1280 * Not sure what exactly "address belongs to the node"
1281 * means in the spec, is it just unicast, or what?
1282 *
1283 * At this moment we consider Subject address as
1284 * "belong to the node" if the Subject address equals
1285 * to the IPv6 destination address; validation for
1286 * IPv6 destination address should have done enough
1287 * check for us.
1288 *
1289 * We do not do proxy at this moment.
1290 */
1291 /* m_pulldown instead of copy? */
1292 m_copydata(m, off + sizeof(struct icmp6_nodeinfo),
1293 subjlen, (caddr_t)&in6_subj);
1294 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL))
1295 goto bad;
1296
1297 subj = (char *)&in6_subj;
1298 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj))
1299 break;
1300
1301 /*
1302 * XXX if we are to allow other cases, we should really
1303 * be careful about scope here.
1304 * basically, we should disallow queries toward IPv6
1305 * destination X with subject Y,
1306 * if scope(X) > scope(Y).
1307 * if we allow scope(X) > scope(Y), it will result in
1308 * information leakage across scope boundary.
1309 */
1310 goto bad;
1311
1312 case ICMP6_NI_SUBJ_FQDN:
1313 /*
1314 * Validate Subject name with gethostname(3).
1315 *
1316 * The behavior may need some debate, since:
1317 * - we are not sure if the node has FQDN as
1318 * hostname (returned by gethostname(3)).
1319 * - the code does wildcard match for truncated names.
1320 * however, we are not sure if we want to perform
1321 * wildcard match, if gethostname(3) side has
1322 * truncated hostname.
1323 */
1324 n = ni6_nametodns(hostname, hostnamelen, 0);
1325 if (!n || n->m_next || n->m_len == 0)
1326 goto bad;
1327 IP6_EXTHDR_GET(subj, char *, m,
1328 off + sizeof(struct icmp6_nodeinfo), subjlen);
1329 if (subj == NULL)
1330 goto bad;
1331 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *),
1332 n->m_len)) {
1333 goto bad;
1334 }
1335 m_freem(n);
1336 n = NULL;
1337 break;
1338
1339 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */
1340 default:
1341 goto bad;
1342 }
1343 break;
1344 }
1345
1346 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */
1347 switch (qtype) {
1348 case NI_QTYPE_FQDN:
1349 if ((icmp6_nodeinfo & ICMP6_NODEINFO_FQDNOK) == 0)
1350 goto bad;
1351 break;
1352 case NI_QTYPE_NODEADDR:
1353 case NI_QTYPE_IPV4ADDR:
1354 if ((icmp6_nodeinfo & ICMP6_NODEINFO_NODEADDROK) == 0)
1355 goto bad;
1356 break;
1357 }
1358
1359 /* guess reply length */
1360 switch (qtype) {
1361 case NI_QTYPE_NOOP:
1362 break; /* no reply data */
1363 case NI_QTYPE_SUPTYPES:
1364 replylen += sizeof(u_int32_t);
1365 break;
1366 case NI_QTYPE_FQDN:
1367 /* XXX will append an mbuf */
1368 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1369 break;
1370 case NI_QTYPE_NODEADDR:
1371 addrs = ni6_addrs(ni6, m, &ifp, (struct in6_addr *)subj);
1372 if ((replylen += addrs * (sizeof(struct in6_addr) +
1373 sizeof(u_int32_t))) > MCLBYTES)
1374 replylen = MCLBYTES; /* XXX: will truncate pkt later */
1375 break;
1376 case NI_QTYPE_IPV4ADDR:
1377 /* unsupported - should respond with unknown Qtype? */
1378 break;
1379 default:
1380 /*
1381 * XXX: We must return a reply with the ICMP6 code
1382 * `unknown Qtype' in this case. However we regard the case
1383 * as an FQDN query for backward compatibility.
1384 * Older versions set a random value to this field,
1385 * so it rarely varies in the defined qtypes.
1386 * But the mechanism is not reliable...
1387 * maybe we should obsolete older versions.
1388 */
1389 qtype = NI_QTYPE_FQDN;
1390 /* XXX will append an mbuf */
1391 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1392 oldfqdn++;
1393 break;
1394 }
1395
1396 /* allocate an mbuf to reply. */
1397 MGETHDR(n, M_DONTWAIT, m->m_type);
1398 if (n == NULL) {
1399 m_freem(m);
1400 return (NULL);
1401 }
1402 M_MOVE_PKTHDR(n, m); /* just for recvif */
1403 if (replylen > MHLEN) {
1404 if (replylen > MCLBYTES) {
1405 /*
1406 * XXX: should we try to allocate more? But MCLBYTES
1407 * is probably much larger than IPV6_MMTU...
1408 */
1409 goto bad;
1410 }
1411 MCLGET(n, M_DONTWAIT);
1412 if ((n->m_flags & M_EXT) == 0) {
1413 goto bad;
1414 }
1415 }
1416 n->m_pkthdr.len = n->m_len = replylen;
1417
1418 /* copy mbuf header and IPv6 + Node Information base headers */
1419 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr));
1420 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1);
1421 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo));
1422
1423 /* qtype dependent procedure */
1424 switch (qtype) {
1425 case NI_QTYPE_NOOP:
1426 nni6->ni_code = ICMP6_NI_SUCCESS;
1427 nni6->ni_flags = 0;
1428 break;
1429 case NI_QTYPE_SUPTYPES:
1430 {
1431 u_int32_t v;
1432 nni6->ni_code = ICMP6_NI_SUCCESS;
1433 nni6->ni_flags = htons(0x0000); /* raw bitmap */
1434 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */
1435 v = (u_int32_t)htonl(0x0000000f);
1436 bcopy(&v, nni6 + 1, sizeof(u_int32_t));
1437 break;
1438 }
1439 case NI_QTYPE_FQDN:
1440 nni6->ni_code = ICMP6_NI_SUCCESS;
1441 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) +
1442 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo));
1443 nni6->ni_flags = 0; /* XXX: meaningless TTL */
1444 fqdn->ni_fqdn_ttl = 0; /* ditto. */
1445 /*
1446 * XXX do we really have FQDN in variable "hostname"?
1447 */
1448 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn);
1449 if (n->m_next == NULL)
1450 goto bad;
1451 /* XXX we assume that n->m_next is not a chain */
1452 if (n->m_next->m_next != NULL)
1453 goto bad;
1454 n->m_pkthdr.len += n->m_next->m_len;
1455 break;
1456 case NI_QTYPE_NODEADDR:
1457 {
1458 int lenlim, copied;
1459
1460 nni6->ni_code = ICMP6_NI_SUCCESS;
1461 n->m_pkthdr.len = n->m_len =
1462 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
1463 lenlim = M_TRAILINGSPACE(n);
1464 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim);
1465 /* XXX: reset mbuf length */
1466 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
1467 sizeof(struct icmp6_nodeinfo) + copied;
1468 break;
1469 }
1470 default:
1471 break; /* XXX impossible! */
1472 }
1473
1474 nni6->ni_type = ICMP6_NI_REPLY;
1475 m_freem(m);
1476 return (n);
1477
1478 bad:
1479 m_freem(m);
1480 if (n)
1481 m_freem(n);
1482 return (NULL);
1483 }
1484 #undef hostnamelen
1485
1486 /*
1487 * make a mbuf with DNS-encoded string. no compression support.
1488 *
1489 * XXX names with less than 2 dots (like "foo" or "foo.section") will be
1490 * treated as truncated name (two \0 at the end). this is a wild guess.
1491 */
1492 static struct mbuf *
1493 ni6_nametodns(name, namelen, old)
1494 const char *name;
1495 int namelen;
1496 int old; /* return pascal string if non-zero */
1497 {
1498 struct mbuf *m;
1499 char *cp, *ep;
1500 const char *p, *q;
1501 int i, len, nterm;
1502
1503 if (old)
1504 len = namelen + 1;
1505 else
1506 len = MCLBYTES;
1507
1508 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */
1509 MGET(m, M_DONTWAIT, MT_DATA);
1510 if (m && len > MLEN) {
1511 MCLGET(m, M_DONTWAIT);
1512 if ((m->m_flags & M_EXT) == 0)
1513 goto fail;
1514 }
1515 if (!m)
1516 goto fail;
1517 m->m_next = NULL;
1518
1519 if (old) {
1520 m->m_len = len;
1521 *mtod(m, char *) = namelen;
1522 bcopy(name, mtod(m, char *) + 1, namelen);
1523 return m;
1524 } else {
1525 m->m_len = 0;
1526 cp = mtod(m, char *);
1527 ep = mtod(m, char *) + M_TRAILINGSPACE(m);
1528
1529 /* if not certain about my name, return empty buffer */
1530 if (namelen == 0)
1531 return m;
1532
1533 /*
1534 * guess if it looks like shortened hostname, or FQDN.
1535 * shortened hostname needs two trailing "\0".
1536 */
1537 i = 0;
1538 for (p = name; p < name + namelen; p++) {
1539 if (*p && *p == '.')
1540 i++;
1541 }
1542 if (i < 2)
1543 nterm = 2;
1544 else
1545 nterm = 1;
1546
1547 p = name;
1548 while (cp < ep && p < name + namelen) {
1549 i = 0;
1550 for (q = p; q < name + namelen && *q && *q != '.'; q++)
1551 i++;
1552 /* result does not fit into mbuf */
1553 if (cp + i + 1 >= ep)
1554 goto fail;
1555 /*
1556 * DNS label length restriction, RFC1035 page 8.
1557 * "i == 0" case is included here to avoid returning
1558 * 0-length label on "foo..bar".
1559 */
1560 if (i <= 0 || i >= 64)
1561 goto fail;
1562 *cp++ = i;
1563 bcopy(p, cp, i);
1564 cp += i;
1565 p = q;
1566 if (p < name + namelen && *p == '.')
1567 p++;
1568 }
1569 /* termination */
1570 if (cp + nterm >= ep)
1571 goto fail;
1572 while (nterm-- > 0)
1573 *cp++ = '\0';
1574 m->m_len = cp - mtod(m, char *);
1575 return m;
1576 }
1577
1578 panic("should not reach here");
1579 /* NOTREACHED */
1580
1581 fail:
1582 if (m)
1583 m_freem(m);
1584 return NULL;
1585 }
1586
1587 /*
1588 * check if two DNS-encoded string matches. takes care of truncated
1589 * form (with \0\0 at the end). no compression support.
1590 * XXX upper/lowercase match (see RFC2065)
1591 */
1592 static int
1593 ni6_dnsmatch(a, alen, b, blen)
1594 const char *a;
1595 int alen;
1596 const char *b;
1597 int blen;
1598 {
1599 const char *a0, *b0;
1600 int l;
1601
1602 /* simplest case - need validation? */
1603 if (alen == blen && bcmp(a, b, alen) == 0)
1604 return 1;
1605
1606 a0 = a;
1607 b0 = b;
1608
1609 /* termination is mandatory */
1610 if (alen < 2 || blen < 2)
1611 return 0;
1612 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0')
1613 return 0;
1614 alen--;
1615 blen--;
1616
1617 while (a - a0 < alen && b - b0 < blen) {
1618 if (a - a0 + 1 > alen || b - b0 + 1 > blen)
1619 return 0;
1620
1621 if ((signed char)a[0] < 0 || (signed char)b[0] < 0)
1622 return 0;
1623 /* we don't support compression yet */
1624 if (a[0] >= 64 || b[0] >= 64)
1625 return 0;
1626
1627 /* truncated case */
1628 if (a[0] == 0 && a - a0 == alen - 1)
1629 return 1;
1630 if (b[0] == 0 && b - b0 == blen - 1)
1631 return 1;
1632 if (a[0] == 0 || b[0] == 0)
1633 return 0;
1634
1635 if (a[0] != b[0])
1636 return 0;
1637 l = a[0];
1638 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen)
1639 return 0;
1640 if (bcmp(a + 1, b + 1, l) != 0)
1641 return 0;
1642
1643 a += 1 + l;
1644 b += 1 + l;
1645 }
1646
1647 if (a - a0 == alen && b - b0 == blen)
1648 return 1;
1649 else
1650 return 0;
1651 }
1652
1653 /*
1654 * calculate the number of addresses to be returned in the node info reply.
1655 */
1656 static int
1657 ni6_addrs(ni6, m, ifpp, subj)
1658 struct icmp6_nodeinfo *ni6;
1659 struct mbuf *m;
1660 struct ifnet **ifpp;
1661 struct in6_addr *subj;
1662 {
1663 struct ifnet *ifp;
1664 struct in6_ifaddr *ifa6;
1665 struct ifaddr *ifa;
1666 int addrs = 0, addrsofif, iffound = 0;
1667 int niflags = ni6->ni_flags;
1668
1669 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) {
1670 switch (ni6->ni_code) {
1671 case ICMP6_NI_SUBJ_IPV6:
1672 if (subj == NULL) /* must be impossible... */
1673 return (0);
1674 break;
1675 default:
1676 /*
1677 * XXX: we only support IPv6 subject address for
1678 * this Qtype.
1679 */
1680 return (0);
1681 }
1682 }
1683
1684 IFNET_RLOCK();
1685 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) {
1686 addrsofif = 0;
1687 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) {
1688 if (ifa->ifa_addr->sa_family != AF_INET6)
1689 continue;
1690 ifa6 = (struct in6_ifaddr *)ifa;
1691
1692 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 &&
1693 IN6_ARE_ADDR_EQUAL(subj, &ifa6->ia_addr.sin6_addr))
1694 iffound = 1;
1695
1696 /*
1697 * IPv4-mapped addresses can only be returned by a
1698 * Node Information proxy, since they represent
1699 * addresses of IPv4-only nodes, which perforce do
1700 * not implement this protocol.
1701 * [icmp-name-lookups-07, Section 5.4]
1702 * So we don't support NI_NODEADDR_FLAG_COMPAT in
1703 * this function at this moment.
1704 */
1705
1706 /* What do we have to do about ::1? */
1707 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
1708 case IPV6_ADDR_SCOPE_LINKLOCAL:
1709 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
1710 continue;
1711 break;
1712 case IPV6_ADDR_SCOPE_SITELOCAL:
1713 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
1714 continue;
1715 break;
1716 case IPV6_ADDR_SCOPE_GLOBAL:
1717 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
1718 continue;
1719 break;
1720 default:
1721 continue;
1722 }
1723
1724 /*
1725 * check if anycast is okay.
1726 * XXX: just experimental. not in the spec.
1727 */
1728 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 &&
1729 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0)
1730 continue; /* we need only unicast addresses */
1731 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
1732 (icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) {
1733 continue;
1734 }
1735 addrsofif++; /* count the address */
1736 }
1737 if (iffound) {
1738 *ifpp = ifp;
1739 IFNET_RUNLOCK();
1740 return (addrsofif);
1741 }
1742
1743 addrs += addrsofif;
1744 }
1745 IFNET_RUNLOCK();
1746
1747 return (addrs);
1748 }
1749
1750 static int
1751 ni6_store_addrs(ni6, nni6, ifp0, resid)
1752 struct icmp6_nodeinfo *ni6, *nni6;
1753 struct ifnet *ifp0;
1754 int resid;
1755 {
1756 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet);
1757 struct in6_ifaddr *ifa6;
1758 struct ifaddr *ifa;
1759 struct ifnet *ifp_dep = NULL;
1760 int copied = 0, allow_deprecated = 0;
1761 u_char *cp = (u_char *)(nni6 + 1);
1762 int niflags = ni6->ni_flags;
1763 u_int32_t ltime;
1764
1765 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL))
1766 return (0); /* needless to copy */
1767
1768 IFNET_RLOCK();
1769 again:
1770
1771 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) {
1772 for (ifa = ifp->if_addrlist.tqh_first; ifa;
1773 ifa = ifa->ifa_list.tqe_next) {
1774 if (ifa->ifa_addr->sa_family != AF_INET6)
1775 continue;
1776 ifa6 = (struct in6_ifaddr *)ifa;
1777
1778 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 &&
1779 allow_deprecated == 0) {
1780 /*
1781 * prefererred address should be put before
1782 * deprecated addresses.
1783 */
1784
1785 /* record the interface for later search */
1786 if (ifp_dep == NULL)
1787 ifp_dep = ifp;
1788
1789 continue;
1790 } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 &&
1791 allow_deprecated != 0)
1792 continue; /* we now collect deprecated addrs */
1793
1794 /* What do we have to do about ::1? */
1795 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
1796 case IPV6_ADDR_SCOPE_LINKLOCAL:
1797 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
1798 continue;
1799 break;
1800 case IPV6_ADDR_SCOPE_SITELOCAL:
1801 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
1802 continue;
1803 break;
1804 case IPV6_ADDR_SCOPE_GLOBAL:
1805 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
1806 continue;
1807 break;
1808 default:
1809 continue;
1810 }
1811
1812 /*
1813 * check if anycast is okay.
1814 * XXX: just experimental. not in the spec.
1815 */
1816 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 &&
1817 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0)
1818 continue;
1819 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
1820 (icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) {
1821 continue;
1822 }
1823
1824 /* now we can copy the address */
1825 if (resid < sizeof(struct in6_addr) +
1826 sizeof(u_int32_t)) {
1827 /*
1828 * We give up much more copy.
1829 * Set the truncate flag and return.
1830 */
1831 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE;
1832 IFNET_RUNLOCK();
1833 return (copied);
1834 }
1835
1836 /*
1837 * Set the TTL of the address.
1838 * The TTL value should be one of the following
1839 * according to the specification:
1840 *
1841 * 1. The remaining lifetime of a DHCP lease on the
1842 * address, or
1843 * 2. The remaining Valid Lifetime of a prefix from
1844 * which the address was derived through Stateless
1845 * Autoconfiguration.
1846 *
1847 * Note that we currently do not support stateful
1848 * address configuration by DHCPv6, so the former
1849 * case can't happen.
1850 */
1851 if (ifa6->ia6_lifetime.ia6t_expire == 0)
1852 ltime = ND6_INFINITE_LIFETIME;
1853 else {
1854 if (ifa6->ia6_lifetime.ia6t_expire >
1855 time_second)
1856 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second);
1857 else
1858 ltime = 0;
1859 }
1860
1861 bcopy(<ime, cp, sizeof(u_int32_t));
1862 cp += sizeof(u_int32_t);
1863
1864 /* copy the address itself */
1865 bcopy(&ifa6->ia_addr.sin6_addr, cp,
1866 sizeof(struct in6_addr));
1867 in6_clearscope((struct in6_addr *)cp); /* XXX */
1868 cp += sizeof(struct in6_addr);
1869
1870 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t));
1871 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t));
1872 }
1873 if (ifp0) /* we need search only on the specified IF */
1874 break;
1875 }
1876
1877 if (allow_deprecated == 0 && ifp_dep != NULL) {
1878 ifp = ifp_dep;
1879 allow_deprecated = 1;
1880
1881 goto again;
1882 }
1883
1884 IFNET_RUNLOCK();
1885
1886 return (copied);
1887 }
1888
1889 /*
1890 * XXX almost dup'ed code with rip6_input.
1891 */
1892 static int
1893 icmp6_rip6_input(mp, off)
1894 struct mbuf **mp;
1895 int off;
1896 {
1897 struct mbuf *m = *mp;
1898 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1899 struct in6pcb *in6p;
1900 struct in6pcb *last = NULL;
1901 struct sockaddr_in6 fromsa;
1902 struct icmp6_hdr *icmp6;
1903 struct mbuf *opts = NULL;
1904
1905 #ifndef PULLDOWN_TEST
1906 /* this is assumed to be safe. */
1907 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
1908 #else
1909 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
1910 if (icmp6 == NULL) {
1911 /* m is already reclaimed */
1912 return (IPPROTO_DONE);
1913 }
1914 #endif
1915
1916 /*
1917 * XXX: the address may have embedded scope zone ID, which should be
1918 * hidden from applications.
1919 */
1920 bzero(&fromsa, sizeof(fromsa));
1921 fromsa.sin6_family = AF_INET6;
1922 fromsa.sin6_len = sizeof(struct sockaddr_in6);
1923 fromsa.sin6_addr = ip6->ip6_src;
1924 if (sa6_recoverscope(&fromsa)) {
1925 m_freem(m);
1926 return (IPPROTO_DONE);
1927 }
1928
1929 INP_INFO_RLOCK(&ripcbinfo);
1930 LIST_FOREACH(in6p, &ripcb, inp_list) {
1931 INP_LOCK(in6p);
1932 if ((in6p->inp_vflag & INP_IPV6) == 0) {
1933 docontinue:
1934 INP_UNLOCK(in6p);
1935 continue;
1936 }
1937 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6)
1938 goto docontinue;
1939 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) &&
1940 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst))
1941 goto docontinue;
1942 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) &&
1943 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src))
1944 goto docontinue;
1945 if (in6p->in6p_icmp6filt
1946 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type,
1947 in6p->in6p_icmp6filt))
1948 goto docontinue;
1949 if (last) {
1950 struct mbuf *n = NULL;
1951
1952 /*
1953 * Recent network drivers tend to allocate a single
1954 * mbuf cluster, rather than to make a couple of
1955 * mbufs without clusters. Also, since the IPv6 code
1956 * path tries to avoid m_pullup(), it is highly
1957 * probable that we still have an mbuf cluster here
1958 * even though the necessary length can be stored in an
1959 * mbuf's internal buffer.
1960 * Meanwhile, the default size of the receive socket
1961 * buffer for raw sockets is not so large. This means
1962 * the possibility of packet loss is relatively higher
1963 * than before. To avoid this scenario, we copy the
1964 * received data to a separate mbuf that does not use
1965 * a cluster, if possible.
1966 * XXX: it is better to copy the data after stripping
1967 * intermediate headers.
1968 */
1969 if ((m->m_flags & M_EXT) && m->m_next == NULL &&
1970 m->m_len <= MHLEN) {
1971 MGET(n, M_DONTWAIT, m->m_type);
1972 if (n != NULL) {
1973 if (m_dup_pkthdr(n, m, M_NOWAIT)) {
1974 bcopy(m->m_data, n->m_data,
1975 m->m_len);
1976 n->m_len = m->m_len;
1977 } else {
1978 m_free(n);
1979 n = NULL;
1980 }
1981 }
1982 }
1983 if (n != NULL ||
1984 (n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
1985 if (last->in6p_flags & IN6P_CONTROLOPTS)
1986 ip6_savecontrol(last, n, &opts);
1987 /* strip intermediate headers */
1988 m_adj(n, off);
1989 if (sbappendaddr(&last->in6p_socket->so_rcv,
1990 (struct sockaddr *)&fromsa, n, opts)
1991 == 0) {
1992 /* should notify about lost packet */
1993 m_freem(n);
1994 if (opts) {
1995 m_freem(opts);
1996 }
1997 } else
1998 sorwakeup(last->in6p_socket);
1999 opts = NULL;
2000 }
2001 INP_UNLOCK(last);
2002 }
2003 last = in6p;
2004 }
2005 if (last) {
2006 if (last->in6p_flags & IN6P_CONTROLOPTS)
2007 ip6_savecontrol(last, m, &opts);
2008 /* strip intermediate headers */
2009 m_adj(m, off);
2010
2011 /* avoid using mbuf clusters if possible (see above) */
2012 if ((m->m_flags & M_EXT) && m->m_next == NULL &&
2013 m->m_len <= MHLEN) {
2014 struct mbuf *n;
2015
2016 MGET(n, M_DONTWAIT, m->m_type);
2017 if (n != NULL) {
2018 if (m_dup_pkthdr(n, m, M_NOWAIT)) {
2019 bcopy(m->m_data, n->m_data, m->m_len);
2020 n->m_len = m->m_len;
2021
2022 m_freem(m);
2023 m = n;
2024 } else {
2025 m_freem(n);
2026 n = NULL;
2027 }
2028 }
2029 }
2030 if (sbappendaddr(&last->in6p_socket->so_rcv,
2031 (struct sockaddr *)&fromsa, m, opts) == 0) {
2032 m_freem(m);
2033 if (opts)
2034 m_freem(opts);
2035 } else
2036 sorwakeup(last->in6p_socket);
2037 INP_UNLOCK(last);
2038 } else {
2039 m_freem(m);
2040 ip6stat.ip6s_delivered--;
2041 }
2042 INP_INFO_RUNLOCK(&ripcbinfo);
2043 return IPPROTO_DONE;
2044 }
2045
2046 /*
2047 * Reflect the ip6 packet back to the source.
2048 * OFF points to the icmp6 header, counted from the top of the mbuf.
2049 */
2050 void
2051 icmp6_reflect(m, off)
2052 struct mbuf *m;
2053 size_t off;
2054 {
2055 struct ip6_hdr *ip6;
2056 struct icmp6_hdr *icmp6;
2057 struct in6_ifaddr *ia;
2058 int plen;
2059 int type, code;
2060 struct ifnet *outif = NULL;
2061 struct in6_addr origdst, *src = NULL;
2062
2063 /* too short to reflect */
2064 if (off < sizeof(struct ip6_hdr)) {
2065 nd6log((LOG_DEBUG,
2066 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n",
2067 (u_long)off, (u_long)sizeof(struct ip6_hdr),
2068 __FILE__, __LINE__));
2069 goto bad;
2070 }
2071
2072 /*
2073 * If there are extra headers between IPv6 and ICMPv6, strip
2074 * off that header first.
2075 */
2076 #ifdef DIAGNOSTIC
2077 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN)
2078 panic("assumption failed in icmp6_reflect");
2079 #endif
2080 if (off > sizeof(struct ip6_hdr)) {
2081 size_t l;
2082 struct ip6_hdr nip6;
2083
2084 l = off - sizeof(struct ip6_hdr);
2085 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6);
2086 m_adj(m, l);
2087 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
2088 if (m->m_len < l) {
2089 if ((m = m_pullup(m, l)) == NULL)
2090 return;
2091 }
2092 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6));
2093 } else /* off == sizeof(struct ip6_hdr) */ {
2094 size_t l;
2095 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
2096 if (m->m_len < l) {
2097 if ((m = m_pullup(m, l)) == NULL)
2098 return;
2099 }
2100 }
2101 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr);
2102 ip6 = mtod(m, struct ip6_hdr *);
2103 ip6->ip6_nxt = IPPROTO_ICMPV6;
2104 icmp6 = (struct icmp6_hdr *)(ip6 + 1);
2105 type = icmp6->icmp6_type; /* keep type for statistics */
2106 code = icmp6->icmp6_code; /* ditto. */
2107
2108 origdst = ip6->ip6_dst;
2109 /*
2110 * ip6_input() drops a packet if its src is multicast.
2111 * So, the src is never multicast.
2112 */
2113 ip6->ip6_dst = ip6->ip6_src;
2114
2115 /*
2116 * If the incoming packet was addressed directly to us (i.e. unicast),
2117 * use dst as the src for the reply.
2118 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible
2119 * (for example) when we encounter an error while forwarding procedure
2120 * destined to a duplicated address of ours.
2121 * Note that ip6_getdstifaddr() may fail if we are in an error handling
2122 * procedure of an outgoing packet of our own, in which case we need
2123 * to search in the ifaddr list.
2124 */
2125 if (!IN6_IS_ADDR_MULTICAST(&origdst)) {
2126 if ((ia = ip6_getdstifaddr(m))) {
2127 if (!(ia->ia6_flags &
2128 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)))
2129 src = &ia->ia_addr.sin6_addr;
2130 } else {
2131 struct sockaddr_in6 d;
2132
2133 bzero(&d, sizeof(d));
2134 d.sin6_family = AF_INET6;
2135 d.sin6_len = sizeof(d);
2136 d.sin6_addr = origdst;
2137 ia = (struct in6_ifaddr *)
2138 ifa_ifwithaddr((struct sockaddr *)&d);
2139 if (ia &&
2140 !(ia->ia6_flags &
2141 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) {
2142 src = &ia->ia_addr.sin6_addr;
2143 }
2144 }
2145 }
2146
2147 if (src == NULL) {
2148 int e;
2149 struct sockaddr_in6 sin6;
2150 struct route_in6 ro;
2151
2152 /*
2153 * This case matches to multicasts, our anycast, or unicasts
2154 * that we do not own. Select a source address based on the
2155 * source address of the erroneous packet.
2156 */
2157 bzero(&sin6, sizeof(sin6));
2158 sin6.sin6_family = AF_INET6;
2159 sin6.sin6_len = sizeof(sin6);
2160 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */
2161
2162 bzero(&ro, sizeof(ro));
2163 src = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &e);
2164 if (ro.ro_rt)
2165 RTFREE(ro.ro_rt); /* XXX: we could use this */
2166 if (src == NULL) {
2167 nd6log((LOG_DEBUG,
2168 "icmp6_reflect: source can't be determined: "
2169 "dst=%s, error=%d\n",
2170 ip6_sprintf(&sin6.sin6_addr), e));
2171 goto bad;
2172 }
2173 }
2174
2175 ip6->ip6_src = *src;
2176 ip6->ip6_flow = 0;
2177 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
2178 ip6->ip6_vfc |= IPV6_VERSION;
2179 ip6->ip6_nxt = IPPROTO_ICMPV6;
2180 if (outif)
2181 ip6->ip6_hlim = ND_IFINFO(outif)->chlim;
2182 else if (m->m_pkthdr.rcvif) {
2183 /* XXX: This may not be the outgoing interface */
2184 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim;
2185 } else
2186 ip6->ip6_hlim = ip6_defhlim;
2187
2188 icmp6->icmp6_cksum = 0;
2189 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6,
2190 sizeof(struct ip6_hdr), plen);
2191
2192 /*
2193 * XXX option handling
2194 */
2195
2196 m->m_flags &= ~(M_BCAST|M_MCAST);
2197
2198 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
2199 if (outif)
2200 icmp6_ifoutstat_inc(outif, type, code);
2201
2202 return;
2203
2204 bad:
2205 m_freem(m);
2206 return;
2207 }
2208
2209 void
2210 icmp6_fasttimo()
2211 {
2212
2213 return;
2214 }
2215
2216 static const char *
2217 icmp6_redirect_diag(src6, dst6, tgt6)
2218 struct in6_addr *src6;
2219 struct in6_addr *dst6;
2220 struct in6_addr *tgt6;
2221 {
2222 static char buf[1024];
2223 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)",
2224 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6));
2225 return buf;
2226 }
2227
2228 void
2229 icmp6_redirect_input(m, off)
2230 struct mbuf *m;
2231 int off;
2232 {
2233 struct ifnet *ifp = m->m_pkthdr.rcvif;
2234 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
2235 struct nd_redirect *nd_rd;
2236 int icmp6len = ntohs(ip6->ip6_plen);
2237 char *lladdr = NULL;
2238 int lladdrlen = 0;
2239 u_char *redirhdr = NULL;
2240 int redirhdrlen = 0;
2241 struct rtentry *rt = NULL;
2242 int is_router;
2243 int is_onlink;
2244 struct in6_addr src6 = ip6->ip6_src;
2245 struct in6_addr redtgt6;
2246 struct in6_addr reddst6;
2247 union nd_opts ndopts;
2248
2249 if (!m || !ifp)
2250 return;
2251
2252 /* XXX if we are router, we don't update route by icmp6 redirect */
2253 if (ip6_forwarding)
2254 goto freeit;
2255 if (!icmp6_rediraccept)
2256 goto freeit;
2257
2258 #ifndef PULLDOWN_TEST
2259 IP6_EXTHDR_CHECK(m, off, icmp6len,);
2260 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off);
2261 #else
2262 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len);
2263 if (nd_rd == NULL) {
2264 icmp6stat.icp6s_tooshort++;
2265 return;
2266 }
2267 #endif
2268 redtgt6 = nd_rd->nd_rd_target;
2269 reddst6 = nd_rd->nd_rd_dst;
2270
2271 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) ||
2272 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) {
2273 goto freeit;
2274 }
2275
2276 /* validation */
2277 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) {
2278 nd6log((LOG_ERR,
2279 "ICMP6 redirect sent from %s rejected; "
2280 "must be from linklocal\n",
2281 ip6_sprintf(&src6)));
2282 goto bad;
2283 }
2284 if (ip6->ip6_hlim != 255) {
2285 nd6log((LOG_ERR,
2286 "ICMP6 redirect sent from %s rejected; "
2287 "hlim=%d (must be 255)\n",
2288 ip6_sprintf(&src6), ip6->ip6_hlim));
2289 goto bad;
2290 }
2291 {
2292 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */
2293 struct sockaddr_in6 sin6;
2294 struct in6_addr *gw6;
2295
2296 bzero(&sin6, sizeof(sin6));
2297 sin6.sin6_family = AF_INET6;
2298 sin6.sin6_len = sizeof(struct sockaddr_in6);
2299 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6));
2300 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL);
2301 if (rt) {
2302 if (rt->rt_gateway == NULL ||
2303 rt->rt_gateway->sa_family != AF_INET6) {
2304 nd6log((LOG_ERR,
2305 "ICMP6 redirect rejected; no route "
2306 "with inet6 gateway found for redirect dst: %s\n",
2307 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2308 RTFREE_LOCKED(rt);
2309 goto bad;
2310 }
2311
2312 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr);
2313 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) {
2314 nd6log((LOG_ERR,
2315 "ICMP6 redirect rejected; "
2316 "not equal to gw-for-src=%s (must be same): "
2317 "%s\n",
2318 ip6_sprintf(gw6),
2319 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2320 RTFREE_LOCKED(rt);
2321 goto bad;
2322 }
2323 } else {
2324 nd6log((LOG_ERR,
2325 "ICMP6 redirect rejected; "
2326 "no route found for redirect dst: %s\n",
2327 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2328 goto bad;
2329 }
2330 RTFREE_LOCKED(rt);
2331 rt = NULL;
2332 }
2333 if (IN6_IS_ADDR_MULTICAST(&reddst6)) {
2334 nd6log((LOG_ERR,
2335 "ICMP6 redirect rejected; "
2336 "redirect dst must be unicast: %s\n",
2337 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2338 goto bad;
2339 }
2340
2341 is_router = is_onlink = 0;
2342 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
2343 is_router = 1; /* router case */
2344 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0)
2345 is_onlink = 1; /* on-link destination case */
2346 if (!is_router && !is_onlink) {
2347 nd6log((LOG_ERR,
2348 "ICMP6 redirect rejected; "
2349 "neither router case nor onlink case: %s\n",
2350 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2351 goto bad;
2352 }
2353 /* validation passed */
2354
2355 icmp6len -= sizeof(*nd_rd);
2356 nd6_option_init(nd_rd + 1, icmp6len, &ndopts);
2357 if (nd6_options(&ndopts) < 0) {
2358 nd6log((LOG_INFO, "icmp6_redirect_input: "
2359 "invalid ND option, rejected: %s\n",
2360 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2361 /* nd6_options have incremented stats */
2362 goto freeit;
2363 }
2364
2365 if (ndopts.nd_opts_tgt_lladdr) {
2366 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
2367 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
2368 }
2369
2370 if (ndopts.nd_opts_rh) {
2371 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len;
2372 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */
2373 }
2374
2375 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
2376 nd6log((LOG_INFO,
2377 "icmp6_redirect_input: lladdrlen mismatch for %s "
2378 "(if %d, icmp6 packet %d): %s\n",
2379 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2,
2380 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2381 goto bad;
2382 }
2383
2384 /* RFC 2461 8.3 */
2385 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT,
2386 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER);
2387
2388 if (!is_onlink) { /* better router case. perform rtredirect. */
2389 /* perform rtredirect */
2390 struct sockaddr_in6 sdst;
2391 struct sockaddr_in6 sgw;
2392 struct sockaddr_in6 ssrc;
2393
2394 bzero(&sdst, sizeof(sdst));
2395 bzero(&sgw, sizeof(sgw));
2396 bzero(&ssrc, sizeof(ssrc));
2397 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6;
2398 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len =
2399 sizeof(struct sockaddr_in6);
2400 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr));
2401 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
2402 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr));
2403 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw,
2404 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST,
2405 (struct sockaddr *)&ssrc);
2406 }
2407 /* finally update cached route in each socket via pfctlinput */
2408 {
2409 struct sockaddr_in6 sdst;
2410
2411 bzero(&sdst, sizeof(sdst));
2412 sdst.sin6_family = AF_INET6;
2413 sdst.sin6_len = sizeof(struct sockaddr_in6);
2414 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
2415 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst);
2416 #if defined(IPSEC) || defined(FAST_IPSEC)
2417 key_sa_routechange((struct sockaddr *)&sdst);
2418 #endif
2419 }
2420
2421 freeit:
2422 m_freem(m);
2423 return;
2424
2425 bad:
2426 icmp6stat.icp6s_badredirect++;
2427 m_freem(m);
2428 }
2429
2430 void
2431 icmp6_redirect_output(m0, rt)
2432 struct mbuf *m0;
2433 struct rtentry *rt;
2434 {
2435 struct ifnet *ifp; /* my outgoing interface */
2436 struct in6_addr *ifp_ll6;
2437 struct in6_addr *router_ll6;
2438 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */
2439 struct mbuf *m = NULL; /* newly allocated one */
2440 struct ip6_hdr *ip6; /* m as struct ip6_hdr */
2441 struct nd_redirect *nd_rd;
2442 size_t maxlen;
2443 u_char *p;
2444 struct ifnet *outif = NULL;
2445 struct sockaddr_in6 src_sa;
2446
2447 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0);
2448
2449 /* if we are not router, we don't send icmp6 redirect */
2450 if (!ip6_forwarding)
2451 goto fail;
2452
2453 /* sanity check */
2454 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp))
2455 goto fail;
2456
2457 /*
2458 * Address check:
2459 * the source address must identify a neighbor, and
2460 * the destination address must not be a multicast address
2461 * [RFC 2461, sec 8.2]
2462 */
2463 sip6 = mtod(m0, struct ip6_hdr *);
2464 bzero(&src_sa, sizeof(src_sa));
2465 src_sa.sin6_family = AF_INET6;
2466 src_sa.sin6_len = sizeof(src_sa);
2467 src_sa.sin6_addr = sip6->ip6_src;
2468 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0)
2469 goto fail;
2470 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst))
2471 goto fail; /* what should we do here? */
2472
2473 /* rate limit */
2474 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0))
2475 goto fail;
2476
2477 /*
2478 * Since we are going to append up to 1280 bytes (= IPV6_MMTU),
2479 * we almost always ask for an mbuf cluster for simplicity.
2480 * (MHLEN < IPV6_MMTU is almost always true)
2481 */
2482 #if IPV6_MMTU >= MCLBYTES
2483 # error assumption failed about IPV6_MMTU and MCLBYTES
2484 #endif
2485 MGETHDR(m, M_DONTWAIT, MT_HEADER);
2486 if (m && IPV6_MMTU >= MHLEN)
2487 MCLGET(m, M_DONTWAIT);
2488 if (!m)
2489 goto fail;
2490 m->m_pkthdr.rcvif = NULL;
2491 m->m_len = 0;
2492 maxlen = M_TRAILINGSPACE(m);
2493 maxlen = min(IPV6_MMTU, maxlen);
2494 /* just for safety */
2495 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) +
2496 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) {
2497 goto fail;
2498 }
2499
2500 {
2501 /* get ip6 linklocal address for ifp(my outgoing interface). */
2502 struct in6_ifaddr *ia;
2503 if ((ia = in6ifa_ifpforlinklocal(ifp,
2504 IN6_IFF_NOTREADY|
2505 IN6_IFF_ANYCAST)) == NULL)
2506 goto fail;
2507 ifp_ll6 = &ia->ia_addr.sin6_addr;
2508 }
2509
2510 /* get ip6 linklocal address for the router. */
2511 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) {
2512 struct sockaddr_in6 *sin6;
2513 sin6 = (struct sockaddr_in6 *)rt->rt_gateway;
2514 router_ll6 = &sin6->sin6_addr;
2515 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6))
2516 router_ll6 = (struct in6_addr *)NULL;
2517 } else
2518 router_ll6 = (struct in6_addr *)NULL;
2519
2520 /* ip6 */
2521 ip6 = mtod(m, struct ip6_hdr *);
2522 ip6->ip6_flow = 0;
2523 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
2524 ip6->ip6_vfc |= IPV6_VERSION;
2525 /* ip6->ip6_plen will be set later */
2526 ip6->ip6_nxt = IPPROTO_ICMPV6;
2527 ip6->ip6_hlim = 255;
2528 /* ip6->ip6_src must be linklocal addr for my outgoing if. */
2529 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr));
2530 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr));
2531
2532 /* ND Redirect */
2533 nd_rd = (struct nd_redirect *)(ip6 + 1);
2534 nd_rd->nd_rd_type = ND_REDIRECT;
2535 nd_rd->nd_rd_code = 0;
2536 nd_rd->nd_rd_reserved = 0;
2537 if (rt->rt_flags & RTF_GATEWAY) {
2538 /*
2539 * nd_rd->nd_rd_target must be a link-local address in
2540 * better router cases.
2541 */
2542 if (!router_ll6)
2543 goto fail;
2544 bcopy(router_ll6, &nd_rd->nd_rd_target,
2545 sizeof(nd_rd->nd_rd_target));
2546 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2547 sizeof(nd_rd->nd_rd_dst));
2548 } else {
2549 /* make sure redtgt == reddst */
2550 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target,
2551 sizeof(nd_rd->nd_rd_target));
2552 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2553 sizeof(nd_rd->nd_rd_dst));
2554 }
2555
2556 p = (u_char *)(nd_rd + 1);
2557
2558 if (!router_ll6)
2559 goto nolladdropt;
2560
2561 {
2562 /* target lladdr option */
2563 struct rtentry *rt_router = NULL;
2564 int len;
2565 struct sockaddr_dl *sdl;
2566 struct nd_opt_hdr *nd_opt;
2567 char *lladdr;
2568
2569 rt_router = nd6_lookup(router_ll6, 0, ifp);
2570 if (!rt_router)
2571 goto nolladdropt;
2572 len = sizeof(*nd_opt) + ifp->if_addrlen;
2573 len = (len + 7) & ~7; /* round by 8 */
2574 /* safety check */
2575 if (len + (p - (u_char *)ip6) > maxlen)
2576 goto nolladdropt;
2577 if (!(rt_router->rt_flags & RTF_GATEWAY) &&
2578 (rt_router->rt_flags & RTF_LLINFO) &&
2579 (rt_router->rt_gateway->sa_family == AF_LINK) &&
2580 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) &&
2581 sdl->sdl_alen) {
2582 nd_opt = (struct nd_opt_hdr *)p;
2583 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
2584 nd_opt->nd_opt_len = len >> 3;
2585 lladdr = (char *)(nd_opt + 1);
2586 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen);
2587 p += len;
2588 }
2589 }
2590 nolladdropt:;
2591
2592 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2593
2594 /* just to be safe */
2595 #ifdef M_DECRYPTED /*not openbsd*/
2596 if (m0->m_flags & M_DECRYPTED)
2597 goto noredhdropt;
2598 #endif
2599 if (p - (u_char *)ip6 > maxlen)
2600 goto noredhdropt;
2601
2602 {
2603 /* redirected header option */
2604 int len;
2605 struct nd_opt_rd_hdr *nd_opt_rh;
2606
2607 /*
2608 * compute the maximum size for icmp6 redirect header option.
2609 * XXX room for auth header?
2610 */
2611 len = maxlen - (p - (u_char *)ip6);
2612 len &= ~7;
2613
2614 /* This is just for simplicity. */
2615 if (m0->m_pkthdr.len != m0->m_len) {
2616 if (m0->m_next) {
2617 m_freem(m0->m_next);
2618 m0->m_next = NULL;
2619 }
2620 m0->m_pkthdr.len = m0->m_len;
2621 }
2622
2623 /*
2624 * Redirected header option spec (RFC2461 4.6.3) talks nothing
2625 * about padding/truncate rule for the original IP packet.
2626 * From the discussion on IPv6imp in Feb 1999,
2627 * the consensus was:
2628 * - "attach as much as possible" is the goal
2629 * - pad if not aligned (original size can be guessed by
2630 * original ip6 header)
2631 * Following code adds the padding if it is simple enough,
2632 * and truncates if not.
2633 */
2634 if (m0->m_next || m0->m_pkthdr.len != m0->m_len)
2635 panic("assumption failed in %s:%d", __FILE__,
2636 __LINE__);
2637
2638 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) {
2639 /* not enough room, truncate */
2640 m0->m_pkthdr.len = m0->m_len = len -
2641 sizeof(*nd_opt_rh);
2642 } else {
2643 /* enough room, pad or truncate */
2644 size_t extra;
2645
2646 extra = m0->m_pkthdr.len % 8;
2647 if (extra) {
2648 /* pad if easy enough, truncate if not */
2649 if (8 - extra <= M_TRAILINGSPACE(m0)) {
2650 /* pad */
2651 m0->m_len += (8 - extra);
2652 m0->m_pkthdr.len += (8 - extra);
2653 } else {
2654 /* truncate */
2655 m0->m_pkthdr.len -= extra;
2656 m0->m_len -= extra;
2657 }
2658 }
2659 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh);
2660 m0->m_pkthdr.len = m0->m_len = len -
2661 sizeof(*nd_opt_rh);
2662 }
2663
2664 nd_opt_rh = (struct nd_opt_rd_hdr *)p;
2665 bzero(nd_opt_rh, sizeof(*nd_opt_rh));
2666 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER;
2667 nd_opt_rh->nd_opt_rh_len = len >> 3;
2668 p += sizeof(*nd_opt_rh);
2669 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2670
2671 /* connect m0 to m */
2672 m_tag_delete_chain(m0, NULL);
2673 m0->m_flags &= ~M_PKTHDR;
2674 m->m_next = m0;
2675 m->m_pkthdr.len = m->m_len + m0->m_len;
2676 m0 = NULL;
2677 }
2678 noredhdropt:;
2679 if (m0) {
2680 m_freem(m0);
2681 m0 = NULL;
2682 }
2683
2684 /* XXX: clear embedded link IDs in the inner header */
2685 in6_clearscope(&sip6->ip6_src);
2686 in6_clearscope(&sip6->ip6_dst);
2687 in6_clearscope(&nd_rd->nd_rd_target);
2688 in6_clearscope(&nd_rd->nd_rd_dst);
2689
2690 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
2691
2692 nd_rd->nd_rd_cksum = 0;
2693 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6,
2694 sizeof(*ip6), ntohs(ip6->ip6_plen));
2695
2696 /* send the packet to outside... */
2697 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
2698 if (outif) {
2699 icmp6_ifstat_inc(outif, ifs6_out_msg);
2700 icmp6_ifstat_inc(outif, ifs6_out_redirect);
2701 }
2702 icmp6stat.icp6s_outhist[ND_REDIRECT]++;
2703
2704 return;
2705
2706 fail:
2707 if (m)
2708 m_freem(m);
2709 if (m0)
2710 m_freem(m0);
2711 }
2712
2713 /*
2714 * ICMPv6 socket option processing.
2715 */
2716 int
2717 icmp6_ctloutput(so, sopt)
2718 struct socket *so;
2719 struct sockopt *sopt;
2720 {
2721 int error = 0;
2722 int optlen;
2723 struct inpcb *inp = sotoinpcb(so);
2724 int level, op, optname;
2725
2726 if (sopt) {
2727 level = sopt->sopt_level;
2728 op = sopt->sopt_dir;
2729 optname = sopt->sopt_name;
2730 optlen = sopt->sopt_valsize;
2731 } else
2732 level = op = optname = optlen = 0;
2733
2734 if (level != IPPROTO_ICMPV6) {
2735 return EINVAL;
2736 }
2737
2738 switch (op) {
2739 case PRCO_SETOPT:
2740 switch (optname) {
2741 case ICMP6_FILTER:
2742 {
2743 struct icmp6_filter *p;
2744
2745 if (optlen != sizeof(*p)) {
2746 error = EMSGSIZE;
2747 break;
2748 }
2749 if (inp->in6p_icmp6filt == NULL) {
2750 error = EINVAL;
2751 break;
2752 }
2753 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen,
2754 optlen);
2755 break;
2756 }
2757
2758 default:
2759 error = ENOPROTOOPT;
2760 break;
2761 }
2762 break;
2763
2764 case PRCO_GETOPT:
2765 switch (optname) {
2766 case ICMP6_FILTER:
2767 {
2768 if (inp->in6p_icmp6filt == NULL) {
2769 error = EINVAL;
2770 break;
2771 }
2772 error = sooptcopyout(sopt, inp->in6p_icmp6filt,
2773 sizeof(struct icmp6_filter));
2774 break;
2775 }
2776
2777 default:
2778 error = ENOPROTOOPT;
2779 break;
2780 }
2781 break;
2782 }
2783
2784 return (error);
2785 }
2786
2787 /*
2788 * Perform rate limit check.
2789 * Returns 0 if it is okay to send the icmp6 packet.
2790 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate
2791 * limitation.
2792 *
2793 * XXX per-destination/type check necessary?
2794 */
2795 static int
2796 icmp6_ratelimit(dst, type, code)
2797 const struct in6_addr *dst; /* not used at this moment */
2798 const int type; /* not used at this moment */
2799 const int code; /* not used at this moment */
2800 {
2801 int ret;
2802
2803 ret = 0; /* okay to send */
2804
2805 /* PPS limit */
2806 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count,
2807 icmp6errppslim)) {
2808 /* The packet is subject to rate limit */
2809 ret++;
2810 }
2811
2812 return ret;
2813 }
Cache object: a9ce53c57b5ab666187eb6e631cd3e74
|