icmp6.c revision 1.35 1 /* $NetBSD: icmp6.c,v 1.35 2000/07/06 12:36:18 itojun Exp $ */
2 /* $KAME: icmp6.c,v 1.120 2000/07/06 11:47:20 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 * 3. All advertising materials mentioning features or use of this software
46 * must display the following acknowledgement:
47 * This product includes software developed by the University of
48 * California, Berkeley and its contributors.
49 * 4. Neither the name of the University nor the names of its contributors
50 * may be used to endorse or promote products derived from this software
51 * without specific prior written permission.
52 *
53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
63 * SUCH DAMAGE.
64 *
65 * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94
66 */
67
68 #include "opt_inet.h"
69 #include "opt_ipsec.h"
70
71 #include <sys/param.h>
72 #include <sys/systm.h>
73 #include <sys/malloc.h>
74 #include <sys/mbuf.h>
75 #include <sys/protosw.h>
76 #include <sys/socket.h>
77 #include <sys/socketvar.h>
78 #include <sys/time.h>
79 #include <sys/kernel.h>
80 #include <sys/syslog.h>
81 #include <sys/domain.h>
82
83 #include <net/if.h>
84 #include <net/route.h>
85 #include <net/if_dl.h>
86 #include <net/if_types.h>
87
88 #include <netinet/in.h>
89 #include <netinet/in_var.h>
90 #include <netinet/ip6.h>
91 #include <netinet6/ip6_var.h>
92 #include <netinet/icmp6.h>
93 #include <netinet6/mld6_var.h>
94 #include <netinet6/in6_pcb.h>
95 #include <netinet6/nd6.h>
96 #include <netinet6/in6_ifattach.h>
97 #include <netinet6/ip6protosw.h>
98
99
100 #ifdef IPSEC
101 #include <netinet6/ipsec.h>
102 #include <netkey/key.h>
103 #endif
104
105 #include "faith.h"
106
107 #include <net/net_osdep.h>
108
109 extern struct domain inet6domain;
110
111 struct icmp6stat icmp6stat;
112
113 extern struct in6pcb rawin6pcb;
114 extern struct timeval icmp6errratelim;
115 static struct timeval icmp6errratelim_last;
116 extern int icmp6errppslim;
117 static int icmp6errpps_count = 0;
118 extern int icmp6_nodeinfo;
119 static struct rttimer_queue *icmp6_mtudisc_timeout_q = NULL;
120 extern int pmtu_expire;
121
122 static void icmp6_errcount __P((struct icmp6errstat *, int, int));
123 static int icmp6_rip6_input __P((struct mbuf **, int));
124 static void icmp6_mtudisc_update __P((struct in6_addr *, struct icmp6_hdr *,
125 struct mbuf *));
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 **));
134 static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *,
135 struct ifnet *, int));
136 static struct rtentry *icmp6_mtudisc_clone __P((struct sockaddr *));
137 static void icmp6_mtudisc_timeout __P((struct rtentry *, struct rttimer *));
138
139 #ifdef COMPAT_RFC1885
140 static struct route_in6 icmp6_reflect_rt;
141 #endif
142
143 void
144 icmp6_init()
145 {
146 mld6_init();
147 icmp6_mtudisc_timeout_q = rt_timer_queue_create(pmtu_expire);
148 }
149
150 static void
151 icmp6_errcount(stat, type, code)
152 struct icmp6errstat *stat;
153 int type, code;
154 {
155 switch(type) {
156 case ICMP6_DST_UNREACH:
157 switch (code) {
158 case ICMP6_DST_UNREACH_NOROUTE:
159 stat->icp6errs_dst_unreach_noroute++;
160 return;
161 case ICMP6_DST_UNREACH_ADMIN:
162 stat->icp6errs_dst_unreach_admin++;
163 return;
164 case ICMP6_DST_UNREACH_BEYONDSCOPE:
165 stat->icp6errs_dst_unreach_beyondscope++;
166 return;
167 case ICMP6_DST_UNREACH_ADDR:
168 stat->icp6errs_dst_unreach_addr++;
169 return;
170 case ICMP6_DST_UNREACH_NOPORT:
171 stat->icp6errs_dst_unreach_noport++;
172 return;
173 }
174 break;
175 case ICMP6_PACKET_TOO_BIG:
176 stat->icp6errs_packet_too_big++;
177 return;
178 case ICMP6_TIME_EXCEEDED:
179 switch(code) {
180 case ICMP6_TIME_EXCEED_TRANSIT:
181 stat->icp6errs_time_exceed_transit++;
182 return;
183 case ICMP6_TIME_EXCEED_REASSEMBLY:
184 stat->icp6errs_time_exceed_reassembly++;
185 return;
186 }
187 break;
188 case ICMP6_PARAM_PROB:
189 switch(code) {
190 case ICMP6_PARAMPROB_HEADER:
191 stat->icp6errs_paramprob_header++;
192 return;
193 case ICMP6_PARAMPROB_NEXTHEADER:
194 stat->icp6errs_paramprob_nextheader++;
195 return;
196 case ICMP6_PARAMPROB_OPTION:
197 stat->icp6errs_paramprob_option++;
198 return;
199 }
200 break;
201 case ND_REDIRECT:
202 stat->icp6errs_redirect++;
203 return;
204 }
205 stat->icp6errs_unknown++;
206 }
207
208 /*
209 * Generate an error packet of type error in response to bad IP6 packet.
210 */
211 void
212 icmp6_error(m, type, code, param)
213 struct mbuf *m;
214 int type, code, param;
215 {
216 struct ip6_hdr *oip6, *nip6;
217 struct icmp6_hdr *icmp6;
218 u_int preplen;
219 int off;
220 int nxt;
221
222 icmp6stat.icp6s_error++;
223
224 /* count per-type-code statistics */
225 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code);
226
227 if (m->m_flags & M_DECRYPTED) {
228 icmp6stat.icp6s_canterror++;
229 goto freeit;
230 }
231
232 #ifndef PULLDOWN_TEST
233 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), );
234 #else
235 if (m->m_len < sizeof(struct ip6_hdr)) {
236 m = m_pullup(m, sizeof(struct ip6_hdr));
237 if (m == NULL)
238 return;
239 }
240 #endif
241 oip6 = mtod(m, struct ip6_hdr *);
242
243 /*
244 * Multicast destination check. For unrecognized option errors,
245 * this check has already done in ip6_unknown_opt(), so we can
246 * check only for other errors.
247 */
248 if ((m->m_flags & (M_BCAST|M_MCAST) ||
249 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) &&
250 (type != ICMP6_PACKET_TOO_BIG &&
251 (type != ICMP6_PARAM_PROB ||
252 code != ICMP6_PARAMPROB_OPTION)))
253 goto freeit;
254
255 /* Source address check. XXX: the case of anycast source? */
256 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) ||
257 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src))
258 goto freeit;
259
260 /*
261 * If we are about to send ICMPv6 against ICMPv6 error/redirect,
262 * don't do it.
263 */
264 nxt = -1;
265 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
266 if (off >= 0 && nxt == IPPROTO_ICMPV6) {
267 struct icmp6_hdr *icp;
268
269 #ifndef PULLDOWN_TEST
270 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), );
271 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
272 #else
273 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off,
274 sizeof(*icp));
275 if (icp == NULL) {
276 icmp6stat.icp6s_tooshort++;
277 return;
278 }
279 #endif
280 if (icp->icmp6_type < ICMP6_ECHO_REQUEST ||
281 icp->icmp6_type == ND_REDIRECT) {
282 /*
283 * ICMPv6 error
284 * Special case: for redirect (which is
285 * informational) we must not send icmp6 error.
286 */
287 icmp6stat.icp6s_canterror++;
288 goto freeit;
289 } else {
290 /* ICMPv6 informational - send the error */
291 }
292 } else {
293 /* non-ICMPv6 - send the error */
294 }
295
296 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */
297
298 /* Finally, do rate limitation check. */
299 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) {
300 icmp6stat.icp6s_toofreq++;
301 goto freeit;
302 }
303
304 /*
305 * OK, ICMP6 can be generated.
306 */
307
308 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN)
309 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len);
310
311 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
312 M_PREPEND(m, preplen, M_DONTWAIT);
313 if (m && m->m_len < preplen)
314 m = m_pullup(m, preplen);
315 if (m == NULL) {
316 printf("ENOBUFS in icmp6_error %d\n", __LINE__);
317 return;
318 }
319
320 nip6 = mtod(m, struct ip6_hdr *);
321 nip6->ip6_src = oip6->ip6_src;
322 nip6->ip6_dst = oip6->ip6_dst;
323
324 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src))
325 oip6->ip6_src.s6_addr16[1] = 0;
326 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst))
327 oip6->ip6_dst.s6_addr16[1] = 0;
328
329 icmp6 = (struct icmp6_hdr *)(nip6 + 1);
330 icmp6->icmp6_type = type;
331 icmp6->icmp6_code = code;
332 icmp6->icmp6_pptr = htonl((u_int32_t)param);
333
334 icmp6stat.icp6s_outhist[type]++;
335 icmp6_reflect(m, sizeof(struct ip6_hdr)); /*header order: IPv6 - ICMPv6*/
336
337 return;
338
339 freeit:
340 /*
341 * If we can't tell wheter or not we can generate ICMP6, free it.
342 */
343 m_freem(m);
344 }
345
346 /*
347 * Process a received ICMP6 message.
348 */
349 int
350 icmp6_input(mp, offp, proto)
351 struct mbuf **mp;
352 int *offp, proto;
353 {
354 struct mbuf *m = *mp, *n;
355 struct ip6_hdr *ip6, *nip6;
356 struct icmp6_hdr *icmp6, *nicmp6;
357 int off = *offp;
358 int icmp6len = m->m_pkthdr.len - *offp;
359 int code, sum, noff;
360 struct sockaddr_in6 icmp6src;
361
362 #ifndef PULLDOWN_TEST
363 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE);
364 /* m might change if M_LOOP. So, call mtod after this */
365 #endif
366
367 /*
368 * Locate icmp6 structure in mbuf, and check
369 * that not corrupted and of at least minimum length
370 */
371
372 ip6 = mtod(m, struct ip6_hdr *);
373 if (icmp6len < sizeof(struct icmp6_hdr)) {
374 icmp6stat.icp6s_tooshort++;
375 goto freeit;
376 }
377
378 /*
379 * calculate the checksum
380 */
381 #ifndef PULLDOWN_TEST
382 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
383 #else
384 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
385 if (icmp6 == NULL) {
386 icmp6stat.icp6s_tooshort++;
387 return IPPROTO_DONE;
388 }
389 #endif
390 code = icmp6->icmp6_code;
391
392 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) {
393 log(LOG_ERR,
394 "ICMP6 checksum error(%d|%x) %s\n",
395 icmp6->icmp6_type,
396 sum,
397 ip6_sprintf(&ip6->ip6_src));
398 icmp6stat.icp6s_checksum++;
399 goto freeit;
400 }
401
402 #if defined(NFAITH) && 0 < NFAITH
403 if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_type == IFT_FAITH) {
404 /*
405 * Deliver very specific ICMP6 type only.
406 * This is important to deilver TOOBIG. Otherwise PMTUD
407 * will not work.
408 */
409 switch (icmp6->icmp6_type) {
410 case ICMP6_DST_UNREACH:
411 case ICMP6_PACKET_TOO_BIG:
412 case ICMP6_TIME_EXCEEDED:
413 break;
414 default:
415 goto freeit;
416 }
417 }
418 #endif
419
420 #ifdef IPSEC
421 /* drop it if it does not match the default policy */
422 if (ipsec6_in_reject(m, NULL)) {
423 ipsecstat.in_polvio++;
424 goto freeit;
425 }
426 #endif
427
428 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++;
429 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg);
430 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK)
431 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error);
432
433 switch (icmp6->icmp6_type) {
434
435 case ICMP6_DST_UNREACH:
436 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach);
437 switch (code) {
438 case ICMP6_DST_UNREACH_NOROUTE:
439 code = PRC_UNREACH_NET;
440 break;
441 case ICMP6_DST_UNREACH_ADMIN:
442 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib);
443 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */
444 break;
445 case ICMP6_DST_UNREACH_ADDR:
446 code = PRC_HOSTDEAD;
447 break;
448 #ifdef COMPAT_RFC1885
449 case ICMP6_DST_UNREACH_NOTNEIGHBOR:
450 code = PRC_UNREACH_SRCFAIL;
451 break;
452 #else
453 case ICMP6_DST_UNREACH_BEYONDSCOPE:
454 /* I mean "source address was incorrect." */
455 code = PRC_PARAMPROB;
456 break;
457 #endif
458 case ICMP6_DST_UNREACH_NOPORT:
459 code = PRC_UNREACH_PORT;
460 break;
461 default:
462 goto badcode;
463 }
464 goto deliver;
465 break;
466
467 case ICMP6_PACKET_TOO_BIG:
468 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig);
469 if (code != 0)
470 goto badcode;
471
472 code = PRC_MSGSIZE;
473
474 /*
475 * Updating the path MTU will be done after examining
476 * intermediate extension headers.
477 */
478 goto deliver;
479 break;
480
481 case ICMP6_TIME_EXCEEDED:
482 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed);
483 switch (code) {
484 case ICMP6_TIME_EXCEED_TRANSIT:
485 case ICMP6_TIME_EXCEED_REASSEMBLY:
486 code += PRC_TIMXCEED_INTRANS;
487 break;
488 default:
489 goto badcode;
490 }
491 goto deliver;
492 break;
493
494 case ICMP6_PARAM_PROB:
495 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob);
496 switch (code) {
497 case ICMP6_PARAMPROB_NEXTHEADER:
498 code = PRC_UNREACH_PROTOCOL;
499 break;
500 case ICMP6_PARAMPROB_HEADER:
501 case ICMP6_PARAMPROB_OPTION:
502 code = PRC_PARAMPROB;
503 break;
504 default:
505 goto badcode;
506 }
507 goto deliver;
508 break;
509
510 case ICMP6_ECHO_REQUEST:
511 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo);
512 if (code != 0)
513 goto badcode;
514 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) {
515 /* Give up remote */
516 break;
517 }
518 if ((n->m_flags & M_EXT) != 0
519 || n->m_len < off + sizeof(struct icmp6_hdr)) {
520 struct mbuf *n0 = n;
521 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6);
522
523 /*
524 * Prepare an internal mbuf. m_pullup() doesn't
525 * always copy the length we specified.
526 */
527 if (maxlen >= MCLBYTES) {
528 #ifdef DIAGNOSTIC
529 printf("MCLBYTES too small\n");
530 #endif
531 /* Give up remote */
532 m_freem(n0);
533 break;
534 }
535 MGETHDR(n, M_DONTWAIT, n0->m_type);
536 if (n && maxlen >= MHLEN) {
537 MCLGET(n, M_DONTWAIT);
538 if ((n->m_flags & M_EXT) == 0) {
539 m_free(n);
540 n = NULL;
541 }
542 }
543 if (n == NULL) {
544 /* Give up remote */
545 m_freem(n0);
546 break;
547 }
548 M_COPY_PKTHDR(n, n0);
549 /*
550 * Copy IPv6 and ICMPv6 only.
551 */
552 nip6 = mtod(n, struct ip6_hdr *);
553 bcopy(ip6, nip6, sizeof(struct ip6_hdr));
554 nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
555 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
556 noff = sizeof(struct ip6_hdr);
557 n->m_pkthdr.len = n->m_len =
558 noff + sizeof(struct icmp6_hdr);
559 /*
560 * Adjust mbuf. ip6_plen will be adjusted in
561 * ip6_output().
562 */
563 m_adj(n0, off + sizeof(struct icmp6_hdr));
564 n->m_pkthdr.len += n0->m_pkthdr.len;
565 n->m_next = n0;
566 n0->m_flags &= ~M_PKTHDR;
567 } else {
568 nip6 = mtod(n, struct ip6_hdr *);
569 nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off);
570 noff = off;
571 }
572 nicmp6->icmp6_type = ICMP6_ECHO_REPLY;
573 nicmp6->icmp6_code = 0;
574 if (n) {
575 icmp6stat.icp6s_reflect++;
576 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++;
577 icmp6_reflect(n, noff);
578 }
579 break;
580
581 case ICMP6_ECHO_REPLY:
582 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply);
583 if (code != 0)
584 goto badcode;
585 break;
586
587 case MLD6_LISTENER_QUERY:
588 case MLD6_LISTENER_REPORT:
589 if (icmp6len < sizeof(struct mld6_hdr))
590 goto badlen;
591 if (icmp6->icmp6_type == MLD6_LISTENER_QUERY) /* XXX: ugly... */
592 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery);
593 else
594 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport);
595 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
596 /* give up local */
597 mld6_input(m, off);
598 m = NULL;
599 goto freeit;
600 }
601 mld6_input(n, off);
602 /* m stays. */
603 break;
604
605 case MLD6_LISTENER_DONE:
606 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone);
607 if (icmp6len < sizeof(struct mld6_hdr)) /* necessary? */
608 goto badlen;
609 break; /* nothing to be done in kernel */
610
611 case MLD6_MTRACE_RESP:
612 case MLD6_MTRACE:
613 /* XXX: these two are experimental. not officially defind. */
614 /* XXX: per-interface statistics? */
615 break; /* just pass it to applications */
616
617 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */
618 {
619 enum { WRU, FQDN } mode;
620
621 if (!icmp6_nodeinfo)
622 break;
623
624 if (icmp6len == sizeof(struct icmp6_hdr) + 4)
625 mode = WRU;
626 else if (icmp6len >= sizeof(struct icmp6_nodeinfo))
627 mode = FQDN;
628 else
629 goto badlen;
630
631 if (mode == FQDN) {
632 #ifndef PULLDOWN_TEST
633 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo),
634 IPPROTO_DONE);
635 #endif
636 n = m_copy(m, 0, M_COPYALL);
637 if (n)
638 n = ni6_input(n, off);
639 /* XXX meaningless if n == NULL */
640 noff = sizeof(struct ip6_hdr);
641 } else {
642 u_char *p;
643 int maxlen, maxhlen;
644
645 if (code != 0)
646 goto badcode;
647 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4;
648 if (maxlen >= MCLBYTES) {
649 #ifdef DIAGNOSTIC
650 printf("MCLBYTES too small\n");
651 #endif
652 /* Give up remote */
653 break;
654 }
655 MGETHDR(n, M_DONTWAIT, m->m_type);
656 if (n && maxlen > MHLEN) {
657 MCLGET(n, M_DONTWAIT);
658 if ((n->m_flags & M_EXT) == 0) {
659 m_free(n);
660 n = NULL;
661 }
662 }
663 if (n == NULL) {
664 /* Give up remote */
665 break;
666 }
667 n->m_len = 0;
668 maxhlen = M_TRAILINGSPACE(n) - maxlen;
669 if (maxhlen > hostnamelen)
670 maxhlen = hostnamelen;
671 /*
672 * Copy IPv6 and ICMPv6 only.
673 */
674 nip6 = mtod(n, struct ip6_hdr *);
675 bcopy(ip6, nip6, sizeof(struct ip6_hdr));
676 nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
677 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
678 p = (u_char *)(nicmp6 + 1);
679 bzero(p, 4);
680 bcopy(hostname, p + 4, maxhlen); /*meaningless TTL*/
681 noff = sizeof(struct ip6_hdr);
682 M_COPY_PKTHDR(n, m); /* just for recvif */
683 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
684 sizeof(struct icmp6_hdr) + 4 + maxhlen;
685 nicmp6->icmp6_type = ICMP6_WRUREPLY;
686 nicmp6->icmp6_code = 0;
687 }
688 #undef hostnamelen
689 if (n) {
690 icmp6stat.icp6s_reflect++;
691 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++;
692 icmp6_reflect(n, noff);
693 }
694 break;
695 }
696
697 case ICMP6_WRUREPLY:
698 if (code != 0)
699 goto badcode;
700 break;
701
702 case ND_ROUTER_SOLICIT:
703 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit);
704 if (code != 0)
705 goto badcode;
706 if (icmp6len < sizeof(struct nd_router_solicit))
707 goto badlen;
708 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
709 /* give up local */
710 nd6_rs_input(m, off, icmp6len);
711 m = NULL;
712 goto freeit;
713 }
714 nd6_rs_input(n, off, icmp6len);
715 /* m stays. */
716 break;
717
718 case ND_ROUTER_ADVERT:
719 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert);
720 if (code != 0)
721 goto badcode;
722 if (icmp6len < sizeof(struct nd_router_advert))
723 goto badlen;
724 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
725 /* give up local */
726 nd6_ra_input(m, off, icmp6len);
727 m = NULL;
728 goto freeit;
729 }
730 nd6_ra_input(n, off, icmp6len);
731 /* m stays. */
732 break;
733
734 case ND_NEIGHBOR_SOLICIT:
735 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit);
736 if (code != 0)
737 goto badcode;
738 if (icmp6len < sizeof(struct nd_neighbor_solicit))
739 goto badlen;
740 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
741 /* give up local */
742 nd6_ns_input(m, off, icmp6len);
743 m = NULL;
744 goto freeit;
745 }
746 nd6_ns_input(n, off, icmp6len);
747 /* m stays. */
748 break;
749
750 case ND_NEIGHBOR_ADVERT:
751 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert);
752 if (code != 0)
753 goto badcode;
754 if (icmp6len < sizeof(struct nd_neighbor_advert))
755 goto badlen;
756 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
757 /* give up local */
758 nd6_na_input(m, off, icmp6len);
759 m = NULL;
760 goto freeit;
761 }
762 nd6_na_input(n, off, icmp6len);
763 /* m stays. */
764 break;
765
766 case ND_REDIRECT:
767 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect);
768 if (code != 0)
769 goto badcode;
770 if (icmp6len < sizeof(struct nd_redirect))
771 goto badlen;
772 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
773 /* give up local */
774 icmp6_redirect_input(m, off);
775 m = NULL;
776 goto freeit;
777 }
778 icmp6_redirect_input(n, off);
779 /* m stays. */
780 break;
781
782 case ICMP6_ROUTER_RENUMBERING:
783 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND &&
784 code != ICMP6_ROUTER_RENUMBERING_RESULT)
785 goto badcode;
786 if (icmp6len < sizeof(struct icmp6_router_renum))
787 goto badlen;
788 break;
789
790 default:
791 printf("icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n",
792 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src),
793 ip6_sprintf(&ip6->ip6_dst),
794 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0);
795 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) {
796 /* ICMPv6 error: MUST deliver it by spec... */
797 code = PRC_NCMDS;
798 /* deliver */
799 } else {
800 /* ICMPv6 informational: MUST not deliver */
801 break;
802 }
803 deliver:
804 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) {
805 icmp6stat.icp6s_tooshort++;
806 goto freeit;
807 }
808 #ifndef PULLDOWN_TEST
809 IP6_EXTHDR_CHECK(m, off,
810 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr),
811 IPPROTO_DONE);
812 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
813 #else
814 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
815 sizeof(*icmp6) + sizeof(struct ip6_hdr));
816 if (icmp6 == NULL) {
817 icmp6stat.icp6s_tooshort++;
818 return IPPROTO_DONE;
819 }
820 #endif
821 bzero(&icmp6src, sizeof(icmp6src));
822 icmp6src.sin6_len = sizeof(struct sockaddr_in6);
823 icmp6src.sin6_family = AF_INET6;
824 icmp6src.sin6_addr = ((struct ip6_hdr *)(icmp6 + 1))->ip6_dst;
825
826 /* Detect the upper level protocol */
827 {
828 void (*ctlfunc) __P((int, struct sockaddr *, void *));
829 struct ip6_hdr *eip6 = (struct ip6_hdr *)(icmp6 + 1);
830 u_int8_t nxt = eip6->ip6_nxt;
831 int eoff = off + sizeof(struct icmp6_hdr) +
832 sizeof(struct ip6_hdr);
833 struct ip6ctlparam ip6cp;
834 struct in6_addr *finaldst = NULL;
835 int icmp6type = icmp6->icmp6_type;
836 struct ip6_frag *fh;
837 struct ip6_rthdr *rth;
838 struct ip6_rthdr0 *rth0;
839 int rthlen;
840
841 while (1) { /* XXX: should avoid inf. loop explicitly? */
842 struct ip6_ext *eh;
843
844 switch(nxt) {
845 case IPPROTO_HOPOPTS:
846 case IPPROTO_DSTOPTS:
847 case IPPROTO_AH:
848 #ifndef PULLDOWN_TEST
849 IP6_EXTHDR_CHECK(m, 0, eoff +
850 sizeof(struct ip6_ext),
851 IPPROTO_DONE);
852 eh = (struct ip6_ext *)(mtod(m, caddr_t)
853 + eoff);
854 #else
855 IP6_EXTHDR_GET(eh, struct ip6_ext *, m,
856 eoff, sizeof(*eh));
857 if (eh == NULL) {
858 icmp6stat.icp6s_tooshort++;
859 return IPPROTO_DONE;
860 }
861 #endif
862
863 if (nxt == IPPROTO_AH)
864 eoff += (eh->ip6e_len + 2) << 2;
865 else
866 eoff += (eh->ip6e_len + 1) << 3;
867 nxt = eh->ip6e_nxt;
868 break;
869 case IPPROTO_ROUTING:
870 /*
871 * When the erroneous packet contains a
872 * routing header, we should examine the
873 * header to determine the final destination.
874 * Otherwise, we can't properly update
875 * information that depends on the final
876 * destination (e.g. path MTU).
877 */
878 #ifndef PULLDOWN_TEST
879 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth),
880 IPPROTO_DONE);
881 rth = (struct ip6_rthdr *)(mtod(m, caddr_t)
882 + eoff);
883 #else
884 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m,
885 eoff, sizeof(*rth));
886 if (rth == NULL) {
887 icmp6stat.icp6s_tooshort++;
888 return IPPROTO_DONE;
889 }
890 #endif
891 rthlen = (rth->ip6r_len + 1) << 3;
892 /*
893 * XXX: currently there is no
894 * officially defined type other
895 * than type-0.
896 * Note that if the segment left field
897 * is 0, all intermediate hops must
898 * have been passed.
899 */
900 if (rth->ip6r_segleft &&
901 rth->ip6r_type == IPV6_RTHDR_TYPE_0) {
902 int hops;
903
904 #ifndef PULLDOWN_TEST
905 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen,
906 IPPROTO_DONE);
907 rth0 = (struct ip6_rthdr0 *)(mtod(m, caddr_t) + eoff);
908 #else
909 IP6_EXTHDR_GET(rth0,
910 struct ip6_rthdr0 *, m,
911 eoff, rthlen);
912 if (rth0 == NULL) {
913 icmp6stat.icp6s_tooshort++;
914 return IPPROTO_DONE;
915 }
916 #endif
917 /* just ignore a bogus header */
918 if ((rth0->ip6r0_len % 2) == 0 &&
919 (hops = rth0->ip6r0_len/2))
920 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1);
921 }
922 eoff += rthlen;
923 nxt = rth->ip6r_nxt;
924 break;
925 case IPPROTO_FRAGMENT:
926 #ifndef PULLDOWN_TEST
927 IP6_EXTHDR_CHECK(m, 0, eoff +
928 sizeof(struct ip6_frag),
929 IPPROTO_DONE);
930 fh = (struct ip6_frag *)(mtod(m, caddr_t)
931 + eoff);
932 #else
933 IP6_EXTHDR_GET(fh, struct ip6_frag *, m,
934 eoff, sizeof(*fh));
935 if (fh == NULL) {
936 icmp6stat.icp6s_tooshort++;
937 return IPPROTO_DONE;
938 }
939 #endif
940 /*
941 * Data after a fragment header is meaningless
942 * unless it is the first fragment, but
943 * we'll go to the notify label for path MTU
944 * discovery.
945 */
946 if (fh->ip6f_offlg & IP6F_OFF_MASK)
947 goto notify;
948
949 eoff += sizeof(struct ip6_frag);
950 nxt = fh->ip6f_nxt;
951 break;
952 default:
953 /*
954 * This case includes ESP and the No Next
955 * Header. In such cases going to the notify
956 * label does not have any meaning
957 * (i.e. ctlfunc will be NULL), but we go
958 * anyway since we might have to update
959 * path MTU information.
960 */
961 goto notify;
962 }
963 }
964 notify:
965 #ifndef PULLDOWN_TEST
966 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
967 #else
968 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
969 sizeof(*icmp6) + sizeof(struct ip6_hdr));
970 if (icmp6 == NULL) {
971 icmp6stat.icp6s_tooshort++;
972 return IPPROTO_DONE;
973 }
974 #endif
975 if (icmp6type == ICMP6_PACKET_TOO_BIG) {
976 if (finaldst == NULL)
977 finaldst = &((struct ip6_hdr *)(icmp6 + 1))->ip6_dst;
978 icmp6_mtudisc_update(finaldst, icmp6, m);
979 }
980
981 ctlfunc = (void (*) __P((int, struct sockaddr *, void *)))
982 (inet6sw[ip6_protox[nxt]].pr_ctlinput);
983 if (ctlfunc) {
984 ip6cp.ip6c_m = m;
985 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1);
986 ip6cp.ip6c_off = eoff;
987 (*ctlfunc)(code, (struct sockaddr *)&icmp6src, &ip6cp);
988 }
989 }
990 break;
991
992 badcode:
993 icmp6stat.icp6s_badcode++;
994 break;
995
996 badlen:
997 icmp6stat.icp6s_badlen++;
998 break;
999 }
1000
1001 icmp6_rip6_input(&m, *offp);
1002 return IPPROTO_DONE;
1003
1004 freeit:
1005 m_freem(m);
1006 return IPPROTO_DONE;
1007 }
1008
1009 static void
1010 icmp6_mtudisc_update(dst, icmp6, m)
1011 struct in6_addr *dst;
1012 struct icmp6_hdr *icmp6;/* we can assume the validity of the pointer */
1013 struct mbuf *m; /* currently unused but added for scoped addrs */
1014 {
1015 u_int mtu = ntohl(icmp6->icmp6_mtu);
1016 struct rtentry *rt = NULL;
1017 struct sockaddr_in6 sin6;
1018
1019 bzero(&sin6, sizeof(sin6));
1020 sin6.sin6_family = PF_INET6;
1021 sin6.sin6_len = sizeof(struct sockaddr_in6);
1022 sin6.sin6_addr = *dst;
1023 /* sin6.sin6_scope_id = XXX: should be set if DST is a scoped addr */
1024 rt = rtalloc1((struct sockaddr *)&sin6, 1); /*clone*/
1025 if (!rt || (rt->rt_flags & RTF_HOST) == 0) {
1026 if (rt)
1027 RTFREE(rt);
1028 rt = icmp6_mtudisc_clone((struct sockaddr *)&sin6);
1029 }
1030
1031 if (rt && (rt->rt_flags & RTF_HOST)
1032 && !(rt->rt_rmx.rmx_locks & RTV_MTU)) {
1033 if (mtu < IPV6_MMTU) {
1034 /* xxx */
1035 rt->rt_rmx.rmx_locks |= RTV_MTU;
1036 } else if (mtu < rt->rt_ifp->if_mtu &&
1037 rt->rt_rmx.rmx_mtu > mtu) {
1038 rt->rt_rmx.rmx_mtu = mtu;
1039 }
1040 }
1041 if (rt)
1042 RTFREE(rt);
1043 }
1044
1045 /*
1046 * Process a Node Information Query packet, (roughly) based on
1047 * draft-ietf-ipngwg-icmp-name-lookups-05.
1048 *
1049 * Spec incompatibilities:
1050 * - IPv6 Subject address handling
1051 * - IPv4 Subject address handling support missing
1052 * - Proxy reply (answer even if it's not for me)
1053 * - "Supported Qtypes" support missing
1054 * - joins NI group address at in6_ifattach() time only, does not cope
1055 * with hostname changes by sethostname(3)
1056 */
1057 #ifndef offsetof /* XXX */
1058 #define offsetof(type, member) ((size_t)(&((type *)0)->member))
1059 #endif
1060 static struct mbuf *
1061 ni6_input(m, off)
1062 struct mbuf *m;
1063 int off;
1064 {
1065 struct icmp6_nodeinfo *ni6, *nni6;
1066 struct mbuf *n = NULL;
1067 u_int16_t qtype;
1068 int subjlen;
1069 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
1070 struct ni_reply_fqdn *fqdn;
1071 int addrs; /* for NI_QTYPE_NODEADDR */
1072 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */
1073 struct sockaddr_in6 sin6;
1074 struct ip6_hdr *ip6;
1075 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */
1076 char *subj;
1077
1078 ip6 = mtod(m, struct ip6_hdr *);
1079 #ifndef PULLDOWN_TEST
1080 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off);
1081 #else
1082 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6));
1083 if (ni6 == NULL) {
1084 /* m is already reclaimed */
1085 return NULL;
1086 }
1087 #endif
1088
1089 /*
1090 * Validate IPv6 destination address.
1091 *
1092 * We accept packets with the following IPv6 destination address:
1093 * - Responder's unicast/anycast address,
1094 * - link-local multicast address
1095 * This is a violation to last paragraph in icmp-name-lookups-05
1096 * page 4, which restricts IPv6 destination address of a query to:
1097 * - Responder's unicast/anycast address,
1098 * - NI group address for a name belongs to the Responder, or
1099 * - NI group address for a name for which the Responder is providing
1100 * proxy service.
1101 * (note: NI group address is a link-local multicast address)
1102 *
1103 * We allow any link-local multicast address, since "ping6 -w ff02::1"
1104 * has been really useful for us debugging our network. Also this is
1105 * still questionable if the restriction in spec buy us security at all,
1106 * since RFC2463 permits echo packet to multicast destination.
1107 * Even if we forbid NI query to ff02::1, we can effectively get the
1108 * same result as "ping6 -w ff02::1" by the following steps:
1109 * - run "ping6 ff02::1", then
1110 * - run "ping6 -w" for all addresses replied.
1111 */
1112 bzero(&sin6, sizeof(sin6));
1113 sin6.sin6_family = AF_INET6;
1114 sin6.sin6_len = sizeof(struct sockaddr_in6);
1115 bcopy(&ip6->ip6_dst, &sin6.sin6_addr, sizeof(sin6.sin6_addr));
1116 /* XXX scopeid */
1117 if (ifa_ifwithaddr((struct sockaddr *)&sin6))
1118 ; /*unicast/anycast, fine*/
1119 else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr))
1120 ; /*violates spec slightly, see above*/
1121 else
1122 goto bad;
1123
1124 /* guess reply length */
1125 qtype = ntohs(ni6->ni_qtype);
1126 switch (qtype) {
1127 case NI_QTYPE_NOOP:
1128 break; /* no reply data */
1129 case NI_QTYPE_SUPTYPES:
1130 goto bad; /* xxx: to be implemented */
1131 break;
1132 case NI_QTYPE_FQDN:
1133 /* XXX will append a mbuf */
1134 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1135 break;
1136 case NI_QTYPE_NODEADDR:
1137 addrs = ni6_addrs(ni6, m, &ifp);
1138 if ((replylen += addrs * sizeof(struct in6_addr)) > MCLBYTES)
1139 replylen = MCLBYTES; /* XXX: we'll truncate later */
1140 break;
1141 default:
1142 /*
1143 * XXX: We must return a reply with the ICMP6 code
1144 * `unknown Qtype' in this case. However we regard the case
1145 * as an FQDN query for backward compatibility.
1146 * Older versions set a random value to this field,
1147 * so it rarely varies in the defined qtypes.
1148 * But the mechanism is not reliable...
1149 * maybe we should obsolete older versions.
1150 */
1151 qtype = NI_QTYPE_FQDN;
1152 /* XXX will append a mbuf */
1153 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1154 oldfqdn++;
1155 break;
1156 }
1157
1158 /* validate query Subject field. */
1159 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo);
1160 switch (qtype) {
1161 case NI_QTYPE_NOOP:
1162 case NI_QTYPE_SUPTYPES:
1163 if (subjlen != 0)
1164 goto bad;
1165 break;
1166
1167 case NI_QTYPE_FQDN:
1168 case NI_QTYPE_NODEADDR:
1169 switch (ni6->ni_code) {
1170 case ICMP6_NI_SUBJ_IPV6:
1171 #if ICMP6_NI_SUBJ_IPV6 != 0
1172 case 0:
1173 #endif
1174 /*
1175 * backward compatibility - try to accept 03 draft
1176 * format, where no Subject is present.
1177 */
1178 if (subjlen == 0) {
1179 oldfqdn++;
1180 break;
1181 }
1182
1183 if (subjlen != sizeof(sin6.sin6_addr))
1184 goto bad;
1185
1186 /*
1187 * Validate Subject address.
1188 *
1189 * Not sure what exactly does "address belongs to the
1190 * node" mean in the spec, is it just unicast, or what?
1191 *
1192 * At this moment we consider Subject address as
1193 * "belong to the node" if the Subject address equals
1194 * to the IPv6 destination address; validation for
1195 * IPv6 destination address should have done enough
1196 * check for us.
1197 *
1198 * We do not do proxy at this moment.
1199 */
1200 /* m_pulldown instead of copy? */
1201 m_copydata(m, off + sizeof(struct icmp6_nodeinfo),
1202 subjlen, (caddr_t)&sin6.sin6_addr);
1203 /* XXX kame scope hack */
1204 if (IN6_IS_SCOPE_LINKLOCAL(&sin6.sin6_addr)) {
1205 #ifdef FAKE_LOOPBACK_IF
1206 if ((m->m_flags & M_PKTHDR) != 0 &&
1207 m->m_pkthdr.rcvif) {
1208 sin6.sin6_addr.s6_addr16[1] =
1209 htons(m->m_pkthdr.rcvif->if_index);
1210 }
1211 #else
1212 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
1213 sin6.sin6_addr.s6_addr16[1] =
1214 ip6->ip6_dst.s6_addr16[1];
1215 }
1216 #endif
1217 }
1218 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &sin6.sin6_addr))
1219 break;
1220 /*
1221 * XXX if we are to allow other cases, we should really
1222 * be careful about scope here.
1223 * basically, we should disallow queries toward IPv6
1224 * destination X with subject Y, if scope(X) > scope(Y).
1225 * if we allow scope(X) > scope(Y), it will result in
1226 * information leakage across scope boundary.
1227 */
1228 goto bad;
1229
1230 case ICMP6_NI_SUBJ_FQDN:
1231 /*
1232 * Validate Subject name with gethostname(3).
1233 *
1234 * The behavior may need some debate, since:
1235 * - we are not sure if the node has FQDN as
1236 * hostname (returned by gethostname(3)).
1237 * - the code does wildcard match for truncated names.
1238 * however, we are not sure if we want to perform
1239 * wildcard match, if gethostname(3) side has
1240 * truncated hostname.
1241 */
1242 n = ni6_nametodns(hostname, hostnamelen, 0);
1243 if (!n || n->m_next || n->m_len == 0)
1244 goto bad;
1245 IP6_EXTHDR_GET(subj, char *, m,
1246 off + sizeof(struct icmp6_nodeinfo), subjlen);
1247 if (subj == NULL)
1248 goto bad;
1249 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *),
1250 n->m_len)) {
1251 goto bad;
1252 }
1253 m_freem(n);
1254 n = NULL;
1255 break;
1256
1257 case ICMP6_NI_SUBJ_IPV4: /* xxx: to be implemented? */
1258 default:
1259 goto bad;
1260 }
1261 break;
1262
1263 default:
1264 /* should never be here due to "switch (qtype)" above */
1265 goto bad;
1266 }
1267
1268 /* allocate a mbuf to reply. */
1269 MGETHDR(n, M_DONTWAIT, m->m_type);
1270 if (n == NULL) {
1271 m_freem(m);
1272 return(NULL);
1273 }
1274 M_COPY_PKTHDR(n, m); /* just for recvif */
1275 if (replylen > MHLEN) {
1276 if (replylen > MCLBYTES) {
1277 /*
1278 * XXX: should we try to allocate more? But MCLBYTES is
1279 * probably much larger than IPV6_MMTU...
1280 */
1281 goto bad;
1282 }
1283 MCLGET(n, M_DONTWAIT);
1284 if ((n->m_flags & M_EXT) == 0) {
1285 goto bad;
1286 }
1287 }
1288 n->m_pkthdr.len = n->m_len = replylen;
1289
1290 /* copy mbuf header and IPv6 + Node Information base headers */
1291 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr));
1292 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1);
1293 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo));
1294
1295 /* qtype dependent procedure */
1296 switch (qtype) {
1297 case NI_QTYPE_NOOP:
1298 nni6->ni_flags = 0;
1299 break;
1300 case NI_QTYPE_SUPTYPES:
1301 goto bad; /* xxx: to be implemented */
1302 break;
1303 case NI_QTYPE_FQDN:
1304 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) +
1305 sizeof(struct ip6_hdr) +
1306 sizeof(struct icmp6_nodeinfo));
1307 nni6->ni_flags = 0; /* XXX: meaningless TTL */
1308 fqdn->ni_fqdn_ttl = 0; /* ditto. */
1309 /*
1310 * XXX do we really have FQDN in variable "hostname"?
1311 */
1312 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn);
1313 if (n->m_next == NULL)
1314 goto bad;
1315 /* XXX we assume that n->m_next is not a chain */
1316 if (n->m_next->m_next != NULL)
1317 goto bad;
1318 n->m_pkthdr.len += n->m_next->m_len;
1319 break;
1320 case NI_QTYPE_NODEADDR:
1321 {
1322 int lenlim, copied;
1323
1324 if (n->m_flags & M_EXT)
1325 lenlim = MCLBYTES - sizeof(struct ip6_hdr) -
1326 sizeof(struct icmp6_nodeinfo);
1327 else
1328 lenlim = MHLEN - sizeof(struct ip6_hdr) -
1329 sizeof(struct icmp6_nodeinfo);
1330 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim);
1331 /* XXX: reset mbuf length */
1332 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
1333 sizeof(struct icmp6_nodeinfo) + copied;
1334 break;
1335 }
1336 default:
1337 break; /* XXX impossible! */
1338 }
1339
1340 nni6->ni_type = ICMP6_NI_REPLY;
1341 nni6->ni_code = ICMP6_NI_SUCESS;
1342 m_freem(m);
1343 return(n);
1344
1345 bad:
1346 m_freem(m);
1347 if (n)
1348 m_freem(n);
1349 return(NULL);
1350 }
1351 #undef hostnamelen
1352
1353 /*
1354 * make a mbuf with DNS-encoded string. no compression support.
1355 *
1356 * XXX names with less than 2 dots (like "foo" or "foo.section") will be
1357 * treated as truncated name (two \0 at the end). this is a wild guess.
1358 */
1359 static struct mbuf *
1360 ni6_nametodns(name, namelen, old)
1361 const char *name;
1362 int namelen;
1363 int old; /* return pascal string if non-zero */
1364 {
1365 struct mbuf *m;
1366 char *cp, *ep;
1367 const char *p, *q;
1368 int i, len, nterm;
1369
1370 if (old)
1371 len = namelen + 1;
1372 else
1373 len = MCLBYTES;
1374
1375 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */
1376 MGET(m, M_DONTWAIT, MT_DATA);
1377 if (m && len > MLEN) {
1378 MCLGET(m, M_DONTWAIT);
1379 if ((m->m_flags & M_EXT) == 0)
1380 goto fail;
1381 }
1382 if (!m)
1383 goto fail;
1384 m->m_next = NULL;
1385
1386 if (old) {
1387 m->m_len = len;
1388 *mtod(m, char *) = namelen;
1389 bcopy(name, mtod(m, char *) + 1, namelen);
1390 return m;
1391 } else {
1392 m->m_len = 0;
1393 cp = mtod(m, char *);
1394 ep = mtod(m, char *) + M_TRAILINGSPACE(m);
1395
1396 /* if not certain about my name, return empty buffer */
1397 if (namelen == 0)
1398 return m;
1399
1400 /*
1401 * guess if it looks like shortened hostname, or FQDN.
1402 * shortened hostname needs two trailing "\0".
1403 */
1404 i = 0;
1405 for (p = name; p < name + namelen; p++) {
1406 if (*p && *p == '.')
1407 i++;
1408 }
1409 if (i < 2)
1410 nterm = 2;
1411 else
1412 nterm = 1;
1413
1414 p = name;
1415 while (cp < ep && p < name + namelen) {
1416 i = 0;
1417 for (q = p; q < name + namelen && *q && *q != '.'; q++)
1418 i++;
1419 /* result does not fit into mbuf */
1420 if (cp + i + 1 >= ep)
1421 goto fail;
1422 /* DNS label length restriction, RFC1035 page 8 */
1423 if (i >= 64)
1424 goto fail;
1425 *cp++ = i;
1426 bcopy(p, cp, i);
1427 cp += i;
1428 p = q;
1429 if (p < name + namelen && *p == '.')
1430 p++;
1431 }
1432 /* termination */
1433 if (cp + nterm >= ep)
1434 goto fail;
1435 while (nterm-- > 0)
1436 *cp++ = '\0';
1437 m->m_len = cp - mtod(m, char *);
1438 return m;
1439 }
1440
1441 panic("should not reach here");
1442 /*NOTREACHED*/
1443
1444 fail:
1445 if (m)
1446 m_freem(m);
1447 return NULL;
1448 }
1449
1450 /*
1451 * check if two DNS-encoded string matches. takes care of truncated
1452 * form (with \0\0 at the end). no compression support.
1453 */
1454 static int
1455 ni6_dnsmatch(a, alen, b, blen)
1456 const char *a;
1457 int alen;
1458 const char *b;
1459 int blen;
1460 {
1461 const char *a0, *b0;
1462 int l;
1463
1464 /* simplest case - need validation? */
1465 if (alen == blen && bcmp(a, b, alen) == 0)
1466 return 1;
1467
1468 a0 = a;
1469 b0 = b;
1470
1471 /* termination is mandatory */
1472 if (alen < 2 || blen < 2)
1473 return 0;
1474 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0')
1475 return 0;
1476 alen--;
1477 blen--;
1478
1479 while (a - a0 < alen && b - b0 < blen) {
1480 if (a - a0 + 1 > alen || b - b0 + 1 > blen)
1481 return 0;
1482
1483 if ((signed char)a[0] < 0 || (signed char)b[0] < 0)
1484 return 0;
1485 /* we don't support compression yet */
1486 if (a[0] >= 64 || b[0] >= 64)
1487 return 0;
1488
1489 /* truncated case */
1490 if (a[0] == 0 && a - a0 == alen - 1)
1491 return 1;
1492 if (b[0] == 0 && b - b0 == blen - 1)
1493 return 1;
1494 if (a[0] == 0 || b[0] == 0)
1495 return 0;
1496
1497 if (a[0] != b[0])
1498 return 0;
1499 l = a[0];
1500 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen)
1501 return 0;
1502 if (bcmp(a + 1, b + 1, l) != 0)
1503 return 0;
1504
1505 a += 1 + l;
1506 b += 1 + l;
1507 }
1508
1509 if (a - a0 == alen && b - b0 == blen)
1510 return 1;
1511 else
1512 return 0;
1513 }
1514
1515 /*
1516 * calculate the number of addresses to be returned in the node info reply.
1517 */
1518 static int
1519 ni6_addrs(ni6, m, ifpp)
1520 struct icmp6_nodeinfo *ni6;
1521 struct mbuf *m;
1522 struct ifnet **ifpp;
1523 {
1524 register struct ifnet *ifp;
1525 register struct in6_ifaddr *ifa6;
1526 register struct ifaddr *ifa;
1527 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1528 int addrs = 0, addrsofif, iffound = 0;
1529
1530 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list))
1531 {
1532 addrsofif = 0;
1533 for (ifa = ifp->if_addrlist.tqh_first; ifa;
1534 ifa = ifa->ifa_list.tqe_next)
1535 {
1536 if (ifa->ifa_addr->sa_family != AF_INET6)
1537 continue;
1538 ifa6 = (struct in6_ifaddr *)ifa;
1539
1540 if (!(ni6->ni_flags & NI_NODEADDR_FLAG_ALL) &&
1541 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
1542 &ifa6->ia_addr.sin6_addr))
1543 iffound = 1;
1544
1545 /*
1546 * IPv4-mapped addresses can only be returned by a
1547 * Node Information proxy, since they represent
1548 * addresses of IPv4-only nodes, which perforce do
1549 * not implement this protocol.
1550 * [icmp-name-lookups-05]
1551 * So we don't support NI_NODEADDR_FLAG_COMPAT in
1552 * this function at this moment.
1553 */
1554
1555 if (ifa6->ia6_flags & IN6_IFF_ANYCAST)
1556 continue; /* we need only unicast addresses */
1557
1558 if ((ni6->ni_flags & (NI_NODEADDR_FLAG_LINKLOCAL |
1559 NI_NODEADDR_FLAG_SITELOCAL |
1560 NI_NODEADDR_FLAG_GLOBAL)) == 0)
1561 continue;
1562
1563 /* What do we have to do about ::1? */
1564 switch(in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
1565 case IPV6_ADDR_SCOPE_LINKLOCAL:
1566 if (ni6->ni_flags & NI_NODEADDR_FLAG_LINKLOCAL)
1567 addrsofif++;
1568 break;
1569 case IPV6_ADDR_SCOPE_SITELOCAL:
1570 if (ni6->ni_flags & NI_NODEADDR_FLAG_SITELOCAL)
1571 addrsofif++;
1572 break;
1573 case IPV6_ADDR_SCOPE_GLOBAL:
1574 if (ni6->ni_flags & NI_NODEADDR_FLAG_GLOBAL)
1575 addrsofif++;
1576 break;
1577 default:
1578 continue;
1579 }
1580 }
1581 if (iffound) {
1582 *ifpp = ifp;
1583 return(addrsofif);
1584 }
1585
1586 addrs += addrsofif;
1587 }
1588
1589 return(addrs);
1590 }
1591
1592 static int
1593 ni6_store_addrs(ni6, nni6, ifp0, resid)
1594 struct icmp6_nodeinfo *ni6, *nni6;
1595 struct ifnet *ifp0;
1596 int resid;
1597 {
1598 register struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet);
1599 register struct in6_ifaddr *ifa6;
1600 register struct ifaddr *ifa;
1601 int docopy, copied = 0;
1602 u_char *cp = (u_char *)(nni6 + 1);
1603
1604 if (ifp0 == NULL && !(ni6->ni_flags & NI_NODEADDR_FLAG_ALL))
1605 return(0); /* needless to copy */
1606
1607 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list))
1608 {
1609 for (ifa = ifp->if_addrlist.tqh_first; ifa;
1610 ifa = ifa->ifa_list.tqe_next)
1611 {
1612 docopy = 0;
1613
1614 if (ifa->ifa_addr->sa_family != AF_INET6)
1615 continue;
1616 ifa6 = (struct in6_ifaddr *)ifa;
1617
1618 if (ifa6->ia6_flags & IN6_IFF_ANYCAST) {
1619 /* just experimental. not in the spec. */
1620 if (ni6->ni_flags & NI_NODEADDR_FLAG_ANYCAST)
1621 docopy = 1;
1622 else
1623 continue;
1624 }
1625 else { /* unicast address */
1626 if (ni6->ni_flags & NI_NODEADDR_FLAG_ANYCAST)
1627 continue;
1628 else
1629 docopy = 1;
1630 }
1631
1632 /* What do we have to do about ::1? */
1633 switch(in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
1634 case IPV6_ADDR_SCOPE_LINKLOCAL:
1635 if (ni6->ni_flags & NI_NODEADDR_FLAG_LINKLOCAL)
1636 docopy = 1;
1637 break;
1638 case IPV6_ADDR_SCOPE_SITELOCAL:
1639 if (ni6->ni_flags & NI_NODEADDR_FLAG_SITELOCAL)
1640 docopy = 1;
1641 break;
1642 case IPV6_ADDR_SCOPE_GLOBAL:
1643 if (ni6->ni_flags & NI_NODEADDR_FLAG_GLOBAL)
1644 docopy = 1;
1645 break;
1646 default:
1647 continue;
1648 }
1649
1650 if (docopy) {
1651 if (resid < sizeof(struct in6_addr)) {
1652 /*
1653 * We give up much more copy.
1654 * Set the truncate flag and return.
1655 */
1656 nni6->ni_flags |=
1657 NI_NODEADDR_FLAG_TRUNCATE;
1658 return(copied);
1659 }
1660 bcopy(&ifa6->ia_addr.sin6_addr, cp,
1661 sizeof(struct in6_addr));
1662 /* XXX: KAME link-local hack; remove ifindex */
1663 if (IN6_IS_ADDR_LINKLOCAL(&ifa6->ia_addr.sin6_addr))
1664 ((struct in6_addr *)cp)->s6_addr16[1] = 0;
1665 cp += sizeof(struct in6_addr);
1666 resid -= sizeof(struct in6_addr);
1667 copied += sizeof(struct in6_addr);
1668 }
1669 }
1670 if (ifp0) /* we need search only on the specified IF */
1671 break;
1672 }
1673
1674 return(copied);
1675 }
1676
1677 /*
1678 * XXX almost dup'ed code with rip6_input.
1679 */
1680 static int
1681 icmp6_rip6_input(mp, off)
1682 struct mbuf **mp;
1683 int off;
1684 {
1685 struct mbuf *m = *mp;
1686 register struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1687 register struct in6pcb *in6p;
1688 struct in6pcb *last = NULL;
1689 struct sockaddr_in6 rip6src;
1690 struct icmp6_hdr *icmp6;
1691 struct mbuf *opts = NULL;
1692
1693 #ifndef PULLDOWN_TEST
1694 /* this is assumed to be safe. */
1695 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
1696 #else
1697 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
1698 if (icmp6 == NULL) {
1699 /* m is already reclaimed */
1700 return IPPROTO_DONE;
1701 }
1702 #endif
1703
1704 bzero(&rip6src, sizeof(rip6src));
1705 rip6src.sin6_len = sizeof(struct sockaddr_in6);
1706 rip6src.sin6_family = AF_INET6;
1707 rip6src.sin6_addr = ip6->ip6_src;
1708 if (IN6_IS_SCOPE_LINKLOCAL(&rip6src.sin6_addr))
1709 rip6src.sin6_addr.s6_addr16[1] = 0;
1710 if (m->m_pkthdr.rcvif) {
1711 if (IN6_IS_SCOPE_LINKLOCAL(&rip6src.sin6_addr))
1712 rip6src.sin6_scope_id = m->m_pkthdr.rcvif->if_index;
1713 else
1714 rip6src.sin6_scope_id = 0;
1715 } else
1716 rip6src.sin6_scope_id = 0;
1717
1718 for (in6p = rawin6pcb.in6p_next;
1719 in6p != &rawin6pcb; in6p = in6p->in6p_next)
1720 {
1721 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6)
1722 continue;
1723 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) &&
1724 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst))
1725 continue;
1726 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) &&
1727 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src))
1728 continue;
1729 if (in6p->in6p_icmp6filt
1730 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type,
1731 in6p->in6p_icmp6filt))
1732 continue;
1733 if (last) {
1734 struct mbuf *n;
1735 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
1736 if (last->in6p_flags & IN6P_CONTROLOPTS)
1737 ip6_savecontrol(last, &opts, ip6, n);
1738 /* strip intermediate headers */
1739 m_adj(n, off);
1740 if (sbappendaddr(&last->in6p_socket->so_rcv,
1741 (struct sockaddr *)&rip6src,
1742 n, opts) == 0) {
1743 /* should notify about lost packet */
1744 m_freem(n);
1745 if (opts)
1746 m_freem(opts);
1747 } else
1748 sorwakeup(last->in6p_socket);
1749 opts = NULL;
1750 }
1751 }
1752 last = in6p;
1753 }
1754 if (last) {
1755 if (last->in6p_flags & IN6P_CONTROLOPTS)
1756 ip6_savecontrol(last, &opts, ip6, m);
1757 /* strip intermediate headers */
1758 m_adj(m, off);
1759 if (sbappendaddr(&last->in6p_socket->so_rcv,
1760 (struct sockaddr *)&rip6src, m, opts) == 0) {
1761 m_freem(m);
1762 if (opts)
1763 m_freem(opts);
1764 } else
1765 sorwakeup(last->in6p_socket);
1766 } else {
1767 m_freem(m);
1768 ip6stat.ip6s_delivered--;
1769 }
1770 return IPPROTO_DONE;
1771 }
1772
1773 /*
1774 * Reflect the ip6 packet back to the source.
1775 * OFF points to the icmp6 header, counted from the top of the mbuf.
1776 */
1777 void
1778 icmp6_reflect(m, off)
1779 struct mbuf *m;
1780 size_t off;
1781 {
1782 struct ip6_hdr *ip6;
1783 struct icmp6_hdr *icmp6;
1784 struct in6_ifaddr *ia;
1785 struct in6_addr t, *src = 0;
1786 int plen;
1787 int type, code;
1788 struct ifnet *outif = NULL;
1789 #ifdef COMPAT_RFC1885
1790 int mtu = IPV6_MMTU;
1791 struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst;
1792 #endif
1793
1794 /* too short to reflect */
1795 if (off < sizeof(struct ip6_hdr)) {
1796 printf("sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n",
1797 (u_long)off, (u_long)sizeof(struct ip6_hdr),
1798 __FILE__, __LINE__);
1799 goto bad;
1800 }
1801
1802 /*
1803 * If there are extra headers between IPv6 and ICMPv6, strip
1804 * off that header first.
1805 */
1806 #ifdef DIAGNOSTIC
1807 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN)
1808 panic("assumption failed in icmp6_reflect");
1809 #endif
1810 if (off > sizeof(struct ip6_hdr)) {
1811 size_t l;
1812 struct ip6_hdr nip6;
1813
1814 l = off - sizeof(struct ip6_hdr);
1815 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6);
1816 m_adj(m, l);
1817 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
1818 if (m->m_len < l) {
1819 if ((m = m_pullup(m, l)) == NULL)
1820 return;
1821 }
1822 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6));
1823 } else /* off == sizeof(struct ip6_hdr) */ {
1824 size_t l;
1825 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
1826 if (m->m_len < l) {
1827 if ((m = m_pullup(m, l)) == NULL)
1828 return;
1829 }
1830 }
1831 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr);
1832 ip6 = mtod(m, struct ip6_hdr *);
1833 ip6->ip6_nxt = IPPROTO_ICMPV6;
1834 icmp6 = (struct icmp6_hdr *)(ip6 + 1);
1835 type = icmp6->icmp6_type; /* keep type for statistics */
1836 code = icmp6->icmp6_code; /* ditto. */
1837
1838 t = ip6->ip6_dst;
1839 /*
1840 * ip6_input() drops a packet if its src is multicast.
1841 * So, the src is never multicast.
1842 */
1843 ip6->ip6_dst = ip6->ip6_src;
1844
1845 /* XXX hack for link-local addresses */
1846 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst))
1847 ip6->ip6_dst.s6_addr16[1] =
1848 htons(m->m_pkthdr.rcvif->if_index);
1849 if (IN6_IS_ADDR_LINKLOCAL(&t))
1850 t.s6_addr16[1] = htons(m->m_pkthdr.rcvif->if_index);
1851
1852 #ifdef COMPAT_RFC1885
1853 /*
1854 * xxx guess MTU
1855 * RFC 1885 requires that echo reply should be truncated if it
1856 * does not fit in with (return) path MTU, but the description was
1857 * removed in the new spec.
1858 */
1859 if (icmp6_reflect_rt.ro_rt == 0 ||
1860 ! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) {
1861 if (icmp6_reflect_rt.ro_rt) {
1862 icmp6_reflect_rt.ro_rt = 0;
1863 }
1864 bzero(sin6, sizeof(*sin6));
1865 sin6->sin6_family = PF_INET6;
1866 sin6->sin6_len = sizeof(struct sockaddr_in6);
1867 sin6->sin6_addr = ip6->ip6_dst;
1868
1869 rtalloc((struct route *)&icmp6_reflect_rt.ro_rt);
1870 }
1871
1872 if (icmp6_reflect_rt.ro_rt == 0)
1873 goto bad;
1874
1875 if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST)
1876 && mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu)
1877 mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu;
1878
1879 if (mtu < m->m_pkthdr.len) {
1880 plen -= (m->m_pkthdr.len - mtu);
1881 m_adj(m, mtu - m->m_pkthdr.len);
1882 }
1883 #endif
1884 /*
1885 * If the incoming packet was addressed directly to us(i.e. unicast),
1886 * use dst as the src for the reply.
1887 * The IN6_IFF_NOTREADY case would be VERY rare, but is possible
1888 * (for example) when we encounter an error while forwarding procedure
1889 * destined to a duplicated address of ours.
1890 */
1891 for (ia = in6_ifaddr; ia; ia = ia->ia_next)
1892 if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) &&
1893 (ia->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) {
1894 src = &t;
1895 break;
1896 }
1897 if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) {
1898 /*
1899 * This is the case if the dst is our link-local address
1900 * and the sender is also ourseleves.
1901 */
1902 src = &t;
1903 }
1904
1905 if (src == 0)
1906 /*
1907 * This case matches to multicasts, our anycast, or unicasts
1908 * that we do not own. Select a source address which has the
1909 * same scope.
1910 * XXX: for (non link-local) multicast addresses, this might
1911 * not be a good choice.
1912 */
1913 if ((ia = in6_ifawithscope(m->m_pkthdr.rcvif, &t)) != 0)
1914 src = &IA6_SIN6(ia)->sin6_addr;
1915
1916 if (src == 0)
1917 goto bad;
1918
1919 ip6->ip6_src = *src;
1920
1921 ip6->ip6_flow = 0;
1922 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
1923 ip6->ip6_vfc |= IPV6_VERSION;
1924 ip6->ip6_nxt = IPPROTO_ICMPV6;
1925 if (m->m_pkthdr.rcvif) {
1926 /* XXX: This may not be the outgoing interface */
1927 ip6->ip6_hlim = nd_ifinfo[m->m_pkthdr.rcvif->if_index].chlim;
1928 }
1929
1930 icmp6->icmp6_cksum = 0;
1931 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6,
1932 sizeof(struct ip6_hdr), plen);
1933
1934 /*
1935 * xxx option handling
1936 */
1937
1938 m->m_flags &= ~(M_BCAST|M_MCAST);
1939 #ifdef IPSEC
1940 /* Don't lookup socket */
1941 ipsec_setsocket(m, NULL);
1942 #endif /*IPSEC*/
1943
1944 #ifdef COMPAT_RFC1885
1945 ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif);
1946 #else
1947 ip6_output(m, NULL, NULL, 0, NULL, &outif);
1948 #endif
1949 if (outif)
1950 icmp6_ifoutstat_inc(outif, type, code);
1951
1952 return;
1953
1954 bad:
1955 m_freem(m);
1956 return;
1957 }
1958
1959 void
1960 icmp6_fasttimo()
1961 {
1962
1963 mld6_fasttimeo();
1964
1965 /* reset ICMPv6 pps limit */
1966 icmp6errpps_count = 0;
1967 }
1968
1969 static const char *
1970 icmp6_redirect_diag(src6, dst6, tgt6)
1971 struct in6_addr *src6;
1972 struct in6_addr *dst6;
1973 struct in6_addr *tgt6;
1974 {
1975 static char buf[1024];
1976 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)",
1977 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6));
1978 return buf;
1979 }
1980
1981 void
1982 icmp6_redirect_input(m, off)
1983 register struct mbuf *m;
1984 int off;
1985 {
1986 struct ifnet *ifp = m->m_pkthdr.rcvif;
1987 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1988 struct nd_redirect *nd_rd;
1989 int icmp6len = ntohs(ip6->ip6_plen);
1990 char *lladdr = NULL;
1991 int lladdrlen = 0;
1992 u_char *redirhdr = NULL;
1993 int redirhdrlen = 0;
1994 struct rtentry *rt = NULL;
1995 int is_router;
1996 int is_onlink;
1997 struct in6_addr src6 = ip6->ip6_src;
1998 struct in6_addr redtgt6;
1999 struct in6_addr reddst6;
2000 union nd_opts ndopts;
2001
2002 if (!m || !ifp)
2003 return;
2004
2005 /* XXX if we are router, we don't update route by icmp6 redirect */
2006 if (ip6_forwarding)
2007 goto freeit;
2008 if (!icmp6_rediraccept)
2009 goto freeit;
2010
2011 #ifndef PULLDOWN_TEST
2012 IP6_EXTHDR_CHECK(m, off, icmp6len,);
2013 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off);
2014 #else
2015 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len);
2016 if (nd_rd == NULL) {
2017 icmp6stat.icp6s_tooshort++;
2018 return;
2019 }
2020 #endif
2021 redtgt6 = nd_rd->nd_rd_target;
2022 reddst6 = nd_rd->nd_rd_dst;
2023
2024 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
2025 redtgt6.s6_addr16[1] = htons(ifp->if_index);
2026 if (IN6_IS_ADDR_LINKLOCAL(&reddst6))
2027 reddst6.s6_addr16[1] = htons(ifp->if_index);
2028
2029 /* validation */
2030 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) {
2031 log(LOG_ERR,
2032 "ICMP6 redirect sent from %s rejected; "
2033 "must be from linklocal\n", ip6_sprintf(&src6));
2034 goto freeit;
2035 }
2036 if (ip6->ip6_hlim != 255) {
2037 log(LOG_ERR,
2038 "ICMP6 redirect sent from %s rejected; "
2039 "hlim=%d (must be 255)\n",
2040 ip6_sprintf(&src6), ip6->ip6_hlim);
2041 goto freeit;
2042 }
2043 {
2044 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */
2045 struct sockaddr_in6 sin6;
2046 struct in6_addr *gw6;
2047
2048 bzero(&sin6, sizeof(sin6));
2049 sin6.sin6_family = AF_INET6;
2050 sin6.sin6_len = sizeof(struct sockaddr_in6);
2051 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6));
2052 rt = rtalloc1((struct sockaddr *)&sin6, 0);
2053 if (rt) {
2054 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr);
2055 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) {
2056 log(LOG_ERR,
2057 "ICMP6 redirect rejected; "
2058 "not equal to gw-for-src=%s (must be same): "
2059 "%s\n",
2060 ip6_sprintf(gw6),
2061 icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
2062 RTFREE(rt);
2063 goto freeit;
2064 }
2065 } else {
2066 log(LOG_ERR,
2067 "ICMP6 redirect rejected; "
2068 "no route found for redirect dst: %s\n",
2069 icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
2070 goto freeit;
2071 }
2072 RTFREE(rt);
2073 rt = NULL;
2074 }
2075 if (IN6_IS_ADDR_MULTICAST(&reddst6)) {
2076 log(LOG_ERR,
2077 "ICMP6 redirect rejected; "
2078 "redirect dst must be unicast: %s\n",
2079 icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
2080 goto freeit;
2081 }
2082
2083 is_router = is_onlink = 0;
2084 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
2085 is_router = 1; /* router case */
2086 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0)
2087 is_onlink = 1; /* on-link destination case */
2088 if (!is_router && !is_onlink) {
2089 log(LOG_ERR,
2090 "ICMP6 redirect rejected; "
2091 "neither router case nor onlink case: %s\n",
2092 icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
2093 goto freeit;
2094 }
2095 /* validation passed */
2096
2097 icmp6len -= sizeof(*nd_rd);
2098 nd6_option_init(nd_rd + 1, icmp6len, &ndopts);
2099 if (nd6_options(&ndopts) < 0) {
2100 log(LOG_INFO, "icmp6_redirect_input: "
2101 "invalid ND option, rejected: %s\n",
2102 icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
2103 goto freeit;
2104 }
2105
2106 if (ndopts.nd_opts_tgt_lladdr) {
2107 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
2108 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
2109 }
2110
2111 if (ndopts.nd_opts_rh) {
2112 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len;
2113 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */
2114 }
2115
2116 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
2117 log(LOG_INFO,
2118 "icmp6_redirect_input: lladdrlen mismatch for %s "
2119 "(if %d, icmp6 packet %d): %s\n",
2120 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2,
2121 icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
2122 }
2123
2124 /* RFC 2461 8.3 */
2125 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT,
2126 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER);
2127
2128 if (!is_onlink) { /* better router case. perform rtredirect. */
2129 /* perform rtredirect */
2130 struct sockaddr_in6 sdst;
2131 struct sockaddr_in6 sgw;
2132 struct sockaddr_in6 ssrc;
2133
2134 bzero(&sdst, sizeof(sdst));
2135 bzero(&sgw, sizeof(sgw));
2136 bzero(&ssrc, sizeof(ssrc));
2137 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6;
2138 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len =
2139 sizeof(struct sockaddr_in6);
2140 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr));
2141 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
2142 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr));
2143 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw,
2144 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST,
2145 (struct sockaddr *)&ssrc,
2146 (struct rtentry **)NULL
2147 );
2148 }
2149 /* finally update cached route in each socket via pfctlinput */
2150 {
2151 struct sockaddr_in6 sdst;
2152 #if 1
2153 #else
2154 struct ip6protosw *pr;
2155 #endif
2156
2157 bzero(&sdst, sizeof(sdst));
2158 sdst.sin6_family = AF_INET6;
2159 sdst.sin6_len = sizeof(struct sockaddr_in6);
2160 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
2161 #if 1
2162 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst);
2163 #else
2164 /*
2165 * do not use pfctlinput() here, we have different prototype for
2166 * xx_ctlinput() in ip6proto.
2167 */
2168 for (pr = (struct ip6protosw *)inet6domain.dom_protosw;
2169 pr < (struct ip6protosw *)inet6domain.dom_protoswNPROTOSW;
2170 pr++) {
2171 if (pr->pr_ctlinput) {
2172 (*pr->pr_ctlinput)(PRC_REDIRECT_HOST,
2173 (struct sockaddr *)&sdst, NULL, NULL, 0);
2174 }
2175 }
2176 #endif
2177 #ifdef IPSEC
2178 key_sa_routechange((struct sockaddr *)&sdst);
2179 #endif
2180 }
2181
2182 freeit:
2183 m_freem(m);
2184 }
2185
2186 void
2187 icmp6_redirect_output(m0, rt)
2188 struct mbuf *m0;
2189 struct rtentry *rt;
2190 {
2191 struct ifnet *ifp; /* my outgoing interface */
2192 struct in6_addr *ifp_ll6;
2193 struct in6_addr *router_ll6;
2194 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */
2195 struct mbuf *m = NULL; /* newly allocated one */
2196 struct ip6_hdr *ip6; /* m as struct ip6_hdr */
2197 struct nd_redirect *nd_rd;
2198 size_t maxlen;
2199 u_char *p;
2200 struct ifnet *outif = NULL;
2201 struct sockaddr_in6 src_sa;
2202
2203 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0);
2204
2205 /* if we are not router, we don't send icmp6 redirect */
2206 if (!ip6_forwarding || ip6_accept_rtadv)
2207 goto fail;
2208
2209 /* sanity check */
2210 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp))
2211 goto fail;
2212
2213 /*
2214 * Address check:
2215 * the source address must identify a neighbor, and
2216 * the destination address must not be a multicast address
2217 * [RFC 2461, sec 8.2]
2218 */
2219 sip6 = mtod(m0, struct ip6_hdr *);
2220 bzero(&src_sa, sizeof(src_sa));
2221 src_sa.sin6_family = AF_INET6;
2222 src_sa.sin6_len = sizeof(src_sa);
2223 src_sa.sin6_addr = sip6->ip6_src;
2224 /* we don't currently use sin6_scope_id, but eventually use it */
2225 src_sa.sin6_scope_id = in6_addr2scopeid(ifp, &sip6->ip6_src);
2226 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0)
2227 goto fail;
2228 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst))
2229 goto fail; /* what should we do here? */
2230
2231 /* rate limit */
2232 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0))
2233 goto fail;
2234
2235 /*
2236 * Since we are going to append up to 1280 bytes (= IPV6_MMTU),
2237 * we almost always ask for an mbuf cluster for simplicity.
2238 * (MHLEN < IPV6_MMTU is almost always true)
2239 */
2240 #if IPV6_MMTU >= MCLBYTES
2241 # error assumption failed about IPV6_MMTU and MCLBYTES
2242 #endif
2243 MGETHDR(m, M_DONTWAIT, MT_HEADER);
2244 if (m && IPV6_MMTU >= MHLEN)
2245 MCLGET(m, M_DONTWAIT);
2246 if (!m)
2247 goto fail;
2248 maxlen = (m->m_flags & M_EXT) ? MCLBYTES : MHLEN;
2249 maxlen = min(IPV6_MMTU, maxlen);
2250 /* just for safety */
2251 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) +
2252 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) {
2253 goto fail;
2254 }
2255
2256 {
2257 /* get ip6 linklocal address for ifp(my outgoing interface). */
2258 struct in6_ifaddr *ia;
2259 if ((ia = in6ifa_ifpforlinklocal(ifp,
2260 IN6_IFF_NOTREADY|
2261 IN6_IFF_ANYCAST)) == NULL)
2262 goto fail;
2263 ifp_ll6 = &ia->ia_addr.sin6_addr;
2264 }
2265
2266 /* get ip6 linklocal address for the router. */
2267 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) {
2268 struct sockaddr_in6 *sin6;
2269 sin6 = (struct sockaddr_in6 *)rt->rt_gateway;
2270 router_ll6 = &sin6->sin6_addr;
2271 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6))
2272 router_ll6 = (struct in6_addr *)NULL;
2273 } else
2274 router_ll6 = (struct in6_addr *)NULL;
2275
2276 /* ip6 */
2277 ip6 = mtod(m, struct ip6_hdr *);
2278 ip6->ip6_flow = 0;
2279 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
2280 ip6->ip6_vfc |= IPV6_VERSION;
2281 /* ip6->ip6_plen will be set later */
2282 ip6->ip6_nxt = IPPROTO_ICMPV6;
2283 ip6->ip6_hlim = 255;
2284 /* ip6->ip6_src must be linklocal addr for my outgoing if. */
2285 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr));
2286 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr));
2287
2288 /* ND Redirect */
2289 nd_rd = (struct nd_redirect *)(ip6 + 1);
2290 nd_rd->nd_rd_type = ND_REDIRECT;
2291 nd_rd->nd_rd_code = 0;
2292 nd_rd->nd_rd_reserved = 0;
2293 if (rt->rt_flags & RTF_GATEWAY) {
2294 /*
2295 * nd_rd->nd_rd_target must be a link-local address in
2296 * better router cases.
2297 */
2298 if (!router_ll6)
2299 goto fail;
2300 bcopy(router_ll6, &nd_rd->nd_rd_target,
2301 sizeof(nd_rd->nd_rd_target));
2302 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2303 sizeof(nd_rd->nd_rd_dst));
2304 } else {
2305 /* make sure redtgt == reddst */
2306 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target,
2307 sizeof(nd_rd->nd_rd_target));
2308 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2309 sizeof(nd_rd->nd_rd_dst));
2310 }
2311
2312 p = (u_char *)(nd_rd + 1);
2313
2314 if (!router_ll6)
2315 goto nolladdropt;
2316
2317 {
2318 /* target lladdr option */
2319 struct rtentry *rt_router = NULL;
2320 int len;
2321 struct sockaddr_dl *sdl;
2322 struct nd_opt_hdr *nd_opt;
2323 char *lladdr;
2324
2325 rt_router = nd6_lookup(router_ll6, 0, ifp);
2326 if (!rt_router)
2327 goto nolladdropt;
2328 len = sizeof(*nd_opt) + ifp->if_addrlen;
2329 len = (len + 7) & ~7; /*round by 8*/
2330 /* safety check */
2331 if (len + (p - (u_char *)ip6) > maxlen)
2332 goto nolladdropt;
2333 if (!(rt_router->rt_flags & RTF_GATEWAY) &&
2334 (rt_router->rt_flags & RTF_LLINFO) &&
2335 (rt_router->rt_gateway->sa_family == AF_LINK) &&
2336 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) &&
2337 sdl->sdl_alen) {
2338 nd_opt = (struct nd_opt_hdr *)p;
2339 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
2340 nd_opt->nd_opt_len = len >> 3;
2341 lladdr = (char *)(nd_opt + 1);
2342 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen);
2343 p += len;
2344 }
2345 }
2346 nolladdropt:;
2347
2348 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2349
2350 /* just to be safe */
2351 if (m0->m_flags & M_DECRYPTED)
2352 goto noredhdropt;
2353 if (p - (u_char *)ip6 > maxlen)
2354 goto noredhdropt;
2355
2356 {
2357 /* redirected header option */
2358 int len;
2359 struct nd_opt_rd_hdr *nd_opt_rh;
2360
2361 /*
2362 * compute the maximum size for icmp6 redirect header option.
2363 * XXX room for auth header?
2364 */
2365 len = maxlen - (p - (u_char *)ip6);
2366 len &= ~7;
2367
2368 /* This is just for simplicity. */
2369 if (m0->m_pkthdr.len != m0->m_len) {
2370 if (m0->m_next) {
2371 m_freem(m0->m_next);
2372 m0->m_next = NULL;
2373 }
2374 m0->m_pkthdr.len = m0->m_len;
2375 }
2376
2377 /*
2378 * Redirected header option spec (RFC2461 4.6.3) talks nothing
2379 * about padding/truncate rule for the original IP packet.
2380 * From the discussion on IPv6imp in Feb 1999, the consensus was:
2381 * - "attach as much as possible" is the goal
2382 * - pad if not aligned (original size can be guessed by original
2383 * ip6 header)
2384 * Following code adds the padding if it is simple enough,
2385 * and truncates if not.
2386 */
2387 if (m0->m_next || m0->m_pkthdr.len != m0->m_len)
2388 panic("assumption failed in %s:%d\n", __FILE__, __LINE__);
2389
2390 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) {
2391 /* not enough room, truncate */
2392 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh);
2393 } else {
2394 /* enough room, pad or truncate */
2395 size_t extra;
2396
2397 extra = m0->m_pkthdr.len % 8;
2398 if (extra) {
2399 /* pad if easy enough, truncate if not */
2400 if (8 - extra <= M_TRAILINGSPACE(m0)) {
2401 /* pad */
2402 m0->m_len += (8 - extra);
2403 m0->m_pkthdr.len += (8 - extra);
2404 } else {
2405 /* truncate */
2406 m0->m_pkthdr.len -= extra;
2407 m0->m_len -= extra;
2408 }
2409 }
2410 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh);
2411 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh);
2412 }
2413
2414 nd_opt_rh = (struct nd_opt_rd_hdr *)p;
2415 bzero(nd_opt_rh, sizeof(*nd_opt_rh));
2416 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER;
2417 nd_opt_rh->nd_opt_rh_len = len >> 3;
2418 p += sizeof(*nd_opt_rh);
2419 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2420
2421 /* connect m0 to m */
2422 m->m_next = m0;
2423 m->m_pkthdr.len = m->m_len + m0->m_len;
2424 }
2425 noredhdropt:;
2426
2427 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_src))
2428 sip6->ip6_src.s6_addr16[1] = 0;
2429 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_dst))
2430 sip6->ip6_dst.s6_addr16[1] = 0;
2431 #if 0
2432 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src))
2433 ip6->ip6_src.s6_addr16[1] = 0;
2434 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst))
2435 ip6->ip6_dst.s6_addr16[1] = 0;
2436 #endif
2437 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_target))
2438 nd_rd->nd_rd_target.s6_addr16[1] = 0;
2439 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_dst))
2440 nd_rd->nd_rd_dst.s6_addr16[1] = 0;
2441
2442 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
2443
2444 nd_rd->nd_rd_cksum = 0;
2445 nd_rd->nd_rd_cksum
2446 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen));
2447
2448 /* send the packet to outside... */
2449 #ifdef IPSEC
2450 /* Don't lookup socket */
2451 ipsec_setsocket(m, NULL);
2452 #endif /*IPSEC*/
2453 ip6_output(m, NULL, NULL, 0, NULL, &outif);
2454 if (outif) {
2455 icmp6_ifstat_inc(outif, ifs6_out_msg);
2456 icmp6_ifstat_inc(outif, ifs6_out_redirect);
2457 }
2458 icmp6stat.icp6s_outhist[ND_REDIRECT]++;
2459
2460 return;
2461
2462 fail:
2463 if (m)
2464 m_freem(m);
2465 if (m0)
2466 m_freem(m0);
2467 }
2468
2469 /*
2470 * ICMPv6 socket option processing.
2471 */
2472 int
2473 icmp6_ctloutput(op, so, level, optname, mp)
2474 int op;
2475 struct socket *so;
2476 int level, optname;
2477 struct mbuf **mp;
2478 {
2479 register struct in6pcb *in6p = sotoin6pcb(so);
2480 register struct mbuf *m = *mp;
2481 int error = 0;
2482
2483 if (level != IPPROTO_ICMPV6) {
2484 error = EINVAL;
2485 if (op == PRCO_SETOPT && m)
2486 (void)m_free(m);
2487 } else switch(op) {
2488 case PRCO_SETOPT:
2489 switch (optname) {
2490 case ICMP6_FILTER:
2491 {
2492 struct icmp6_filter *p;
2493
2494 p = mtod(m, struct icmp6_filter *);
2495 if (!p || !in6p->in6p_icmp6filt) {
2496 error = EINVAL;
2497 break;
2498 }
2499 bcopy(p, in6p->in6p_icmp6filt,
2500 sizeof(struct icmp6_filter));
2501 error = 0;
2502 break;
2503 }
2504
2505 default:
2506 error = ENOPROTOOPT;
2507 break;
2508 }
2509 if (m)
2510 (void)m_free(m);
2511 break;
2512
2513 case PRCO_GETOPT:
2514 switch (optname) {
2515 case ICMP6_FILTER:
2516 {
2517 struct icmp6_filter *p;
2518
2519 if (!in6p->in6p_icmp6filt) {
2520 error = EINVAL;
2521 break;
2522 }
2523 *mp = m = m_get(M_WAIT, MT_SOOPTS);
2524 m->m_len = sizeof(struct icmp6_filter);
2525 p = mtod(m, struct icmp6_filter *);
2526 bcopy(in6p->in6p_icmp6filt, p,
2527 sizeof(struct icmp6_filter));
2528 error = 0;
2529 break;
2530 }
2531
2532 default:
2533 error = ENOPROTOOPT;
2534 break;
2535 }
2536 break;
2537 }
2538
2539 return(error);
2540 }
2541
2542 /*
2543 * Perform rate limit check.
2544 * Returns 0 if it is okay to send the icmp6 packet.
2545 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate
2546 * limitation.
2547 *
2548 * There are two limitations defined:
2549 * - pps limit: ICMPv6 error packet cannot exceed defined packet-per-second.
2550 * we measure it every 0.2 second, since fasttimo works every 0.2 second.
2551 * - rate limit: ICMPv6 error packet cannot appear more than once per
2552 * defined interval.
2553 * In any case, if we perform rate limitation, we'll see jitter in the ICMPv6
2554 * error packets.
2555 *
2556 * XXX per-destination/type check necessary?
2557 */
2558 static int
2559 icmp6_ratelimit(dst, type, code)
2560 const struct in6_addr *dst; /* not used at this moment */
2561 const int type; /* not used at this moment */
2562 const int code; /* not used at this moment */
2563 {
2564 int ret;
2565
2566 ret = 0; /*okay to send*/
2567
2568 /* PPS limit */
2569 icmp6errpps_count++;
2570 if (icmp6errppslim && icmp6errpps_count > icmp6errppslim / 5) {
2571 /* The packet is subject to pps limit */
2572 ret++;
2573 }
2574
2575 if (!ratecheck(&icmp6errratelim_last, &icmp6errratelim)) {
2576 /* The packet is subject to rate limit */
2577 ret++;
2578 }
2579
2580 return ret;
2581 }
2582
2583 static struct rtentry *
2584 icmp6_mtudisc_clone(dst)
2585 struct sockaddr *dst;
2586 {
2587 struct rtentry *rt;
2588 int error;
2589
2590 rt = rtalloc1(dst, 1);
2591 if (rt == 0)
2592 return NULL;
2593
2594 /* If we didn't get a host route, allocate one */
2595 if ((rt->rt_flags & RTF_HOST) == 0) {
2596 struct rtentry *nrt;
2597
2598 error = rtrequest((int) RTM_ADD, dst,
2599 (struct sockaddr *) rt->rt_gateway,
2600 (struct sockaddr *) 0,
2601 RTF_GATEWAY | RTF_HOST | RTF_DYNAMIC, &nrt);
2602 if (error) {
2603 rtfree(rt);
2604 rtfree(nrt);
2605 return NULL;
2606 }
2607 nrt->rt_rmx = rt->rt_rmx;
2608 rtfree(rt);
2609 rt = nrt;
2610 }
2611 error = rt_timer_add(rt, icmp6_mtudisc_timeout,
2612 icmp6_mtudisc_timeout_q);
2613 if (error) {
2614 rtfree(rt);
2615 return NULL;
2616 }
2617
2618 return rt; /* caller need to call rtfree() */
2619 }
2620
2621 static void
2622 icmp6_mtudisc_timeout(rt, r)
2623 struct rtentry *rt;
2624 struct rttimer *r;
2625 {
2626 if (rt == NULL)
2627 panic("icmp6_mtudisc_timeout: bad route to timeout");
2628 if ((rt->rt_flags & (RTF_DYNAMIC | RTF_HOST)) ==
2629 (RTF_DYNAMIC | RTF_HOST)) {
2630 rtrequest((int) RTM_DELETE, (struct sockaddr *)rt_key(rt),
2631 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0);
2632 } else {
2633 if ((rt->rt_rmx.rmx_locks & RTV_MTU) == 0) {
2634 rt->rt_rmx.rmx_mtu = 0;
2635 }
2636 }
2637 }
2638
2639 #include <uvm/uvm_extern.h>
2640 #include <sys/sysctl.h>
2641
2642 int
2643 icmp6_sysctl(name, namelen, oldp, oldlenp, newp, newlen)
2644 int *name;
2645 u_int namelen;
2646 void *oldp;
2647 size_t *oldlenp;
2648 void *newp;
2649 size_t newlen;
2650 {
2651
2652 /* All sysctl names at this level are terminal. */
2653 if (namelen != 1)
2654 return ENOTDIR;
2655
2656 switch (name[0]) {
2657
2658 case ICMPV6CTL_REDIRACCEPT:
2659 return sysctl_int(oldp, oldlenp, newp, newlen,
2660 &icmp6_rediraccept);
2661 case ICMPV6CTL_REDIRTIMEOUT:
2662 return sysctl_int(oldp, oldlenp, newp, newlen,
2663 &icmp6_redirtimeout);
2664 case ICMPV6CTL_STATS:
2665 return sysctl_rdstruct(oldp, oldlenp, newp,
2666 &icmp6stat, sizeof(icmp6stat));
2667 case ICMPV6CTL_ERRRATELIMIT:
2668 {
2669 int rate_usec, error, s;
2670
2671 /*
2672 * The sysctl specifies the rate in usec-between-icmp,
2673 * so we must convert from/to a timeval.
2674 */
2675 rate_usec = (icmp6errratelim.tv_sec * 1000000) +
2676 icmp6errratelim.tv_usec;
2677 error = sysctl_int(oldp, oldlenp, newp, newlen, &rate_usec);
2678 if (error)
2679 return (error);
2680 if (rate_usec < 0)
2681 return (EINVAL);
2682 s = splsoftnet();
2683 icmp6errratelim.tv_sec = rate_usec / 1000000;
2684 icmp6errratelim.tv_usec = rate_usec % 1000000;
2685 splx(s);
2686
2687 return (0);
2688 }
2689 case ICMPV6CTL_ND6_PRUNE:
2690 return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_prune);
2691 case ICMPV6CTL_ND6_DELAY:
2692 return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_delay);
2693 case ICMPV6CTL_ND6_UMAXTRIES:
2694 return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_umaxtries);
2695 case ICMPV6CTL_ND6_MMAXTRIES:
2696 return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_mmaxtries);
2697 case ICMPV6CTL_ND6_USELOOPBACK:
2698 return sysctl_int(oldp, oldlenp, newp, newlen,
2699 &nd6_useloopback);
2700 case ICMPV6CTL_NODEINFO:
2701 return sysctl_int(oldp, oldlenp, newp, newlen, &icmp6_nodeinfo);
2702 case ICMPV6CTL_ERRPPSLIMIT:
2703 return sysctl_int(oldp, oldlenp, newp, newlen, &icmp6errppslim);
2704 case ICMPV6CTL_ND6_MAXNUDHINT:
2705 return sysctl_int(oldp, oldlenp, newp, newlen,
2706 &nd6_maxnudhint);
2707 default:
2708 return ENOPROTOOPT;
2709 }
2710 /* NOTREACHED */
2711 }
2712