FreeBSD/Linux Kernel Cross Reference
sys/netinet6/icmp6.c
1 /*-
2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the project nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $KAME: icmp6.c,v 1.211 2001/04/04 05:56:20 itojun Exp $
30 */
31
32 /*-
33 * Copyright (c) 1982, 1986, 1988, 1993
34 * The Regents of the University of California. All rights reserved.
35 *
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions
38 * are met:
39 * 1. Redistributions of source code must retain the above copyright
40 * notice, this list of conditions and the following disclaimer.
41 * 2. Redistributions in binary form must reproduce the above copyright
42 * notice, this list of conditions and the following disclaimer in the
43 * documentation and/or other materials provided with the distribution.
44 * 4. Neither the name of the University nor the names of its contributors
45 * may be used to endorse or promote products derived from this software
46 * without specific prior written permission.
47 *
48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58 * SUCH DAMAGE.
59 *
60 * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94
61 */
62
63 #include <sys/cdefs.h>
64 __FBSDID("$FreeBSD: releng/10.0/sys/netinet6/icmp6.c 257961 2013-11-11 10:43:39Z ae $");
65
66 #include "opt_inet.h"
67 #include "opt_inet6.h"
68 #include "opt_ipsec.h"
69
70 #include <sys/param.h>
71 #include <sys/domain.h>
72 #include <sys/jail.h>
73 #include <sys/kernel.h>
74 #include <sys/lock.h>
75 #include <sys/malloc.h>
76 #include <sys/mbuf.h>
77 #include <sys/proc.h>
78 #include <sys/protosw.h>
79 #include <sys/signalvar.h>
80 #include <sys/socket.h>
81 #include <sys/socketvar.h>
82 #include <sys/sx.h>
83 #include <sys/syslog.h>
84 #include <sys/systm.h>
85 #include <sys/time.h>
86
87 #include <net/if.h>
88 #include <net/if_dl.h>
89 #include <net/if_llatbl.h>
90 #include <net/if_types.h>
91 #include <net/route.h>
92 #include <net/vnet.h>
93
94 #include <netinet/in.h>
95 #include <netinet/in_pcb.h>
96 #include <netinet/in_var.h>
97 #include <netinet/ip6.h>
98 #include <netinet/icmp6.h>
99 #include <netinet/tcp_var.h>
100
101 #include <netinet6/in6_ifattach.h>
102 #include <netinet6/in6_pcb.h>
103 #include <netinet6/ip6protosw.h>
104 #include <netinet6/ip6_var.h>
105 #include <netinet6/scope6_var.h>
106 #include <netinet6/mld6_var.h>
107 #include <netinet6/nd6.h>
108 #include <netinet6/send.h>
109
110 #ifdef IPSEC
111 #include <netipsec/ipsec.h>
112 #include <netipsec/key.h>
113 #endif
114
115 extern struct domain inet6domain;
116
117 VNET_PCPUSTAT_DEFINE(struct icmp6stat, icmp6stat);
118 VNET_PCPUSTAT_SYSINIT(icmp6stat);
119
120 #ifdef VIMAGE
121 VNET_PCPUSTAT_SYSUNINIT(icmp6stat);
122 #endif /* VIMAGE */
123
124 VNET_DECLARE(struct inpcbinfo, ripcbinfo);
125 VNET_DECLARE(struct inpcbhead, ripcb);
126 VNET_DECLARE(int, icmp6errppslim);
127 static VNET_DEFINE(int, icmp6errpps_count) = 0;
128 static VNET_DEFINE(struct timeval, icmp6errppslim_last);
129 VNET_DECLARE(int, icmp6_nodeinfo);
130
131 #define V_ripcbinfo VNET(ripcbinfo)
132 #define V_ripcb VNET(ripcb)
133 #define V_icmp6errppslim VNET(icmp6errppslim)
134 #define V_icmp6errpps_count VNET(icmp6errpps_count)
135 #define V_icmp6errppslim_last VNET(icmp6errppslim_last)
136 #define V_icmp6_nodeinfo VNET(icmp6_nodeinfo)
137
138 static void icmp6_errcount(int, int);
139 static int icmp6_rip6_input(struct mbuf **, int);
140 static int icmp6_ratelimit(const struct in6_addr *, const int, const int);
141 static const char *icmp6_redirect_diag(struct in6_addr *,
142 struct in6_addr *, struct in6_addr *);
143 static struct mbuf *ni6_input(struct mbuf *, int);
144 static struct mbuf *ni6_nametodns(const char *, int, int);
145 static int ni6_dnsmatch(const char *, int, const char *, int);
146 static int ni6_addrs(struct icmp6_nodeinfo *, struct mbuf *,
147 struct ifnet **, struct in6_addr *);
148 static int ni6_store_addrs(struct icmp6_nodeinfo *, struct icmp6_nodeinfo *,
149 struct ifnet *, int);
150 static int icmp6_notify_error(struct mbuf **, int, int, int);
151
152 /*
153 * Kernel module interface for updating icmp6stat. The argument is an index
154 * into icmp6stat treated as an array of u_quad_t. While this encodes the
155 * general layout of icmp6stat into the caller, it doesn't encode its
156 * location, so that future changes to add, for example, per-CPU stats
157 * support won't cause binary compatibility problems for kernel modules.
158 */
159 void
160 kmod_icmp6stat_inc(int statnum)
161 {
162
163 counter_u64_add(VNET(icmp6stat)[statnum], 1);
164 }
165
166 static void
167 icmp6_errcount(int type, int code)
168 {
169 switch (type) {
170 case ICMP6_DST_UNREACH:
171 switch (code) {
172 case ICMP6_DST_UNREACH_NOROUTE:
173 ICMP6STAT_INC(icp6s_odst_unreach_noroute);
174 return;
175 case ICMP6_DST_UNREACH_ADMIN:
176 ICMP6STAT_INC(icp6s_odst_unreach_admin);
177 return;
178 case ICMP6_DST_UNREACH_BEYONDSCOPE:
179 ICMP6STAT_INC(icp6s_odst_unreach_beyondscope);
180 return;
181 case ICMP6_DST_UNREACH_ADDR:
182 ICMP6STAT_INC(icp6s_odst_unreach_addr);
183 return;
184 case ICMP6_DST_UNREACH_NOPORT:
185 ICMP6STAT_INC(icp6s_odst_unreach_noport);
186 return;
187 }
188 break;
189 case ICMP6_PACKET_TOO_BIG:
190 ICMP6STAT_INC(icp6s_opacket_too_big);
191 return;
192 case ICMP6_TIME_EXCEEDED:
193 switch (code) {
194 case ICMP6_TIME_EXCEED_TRANSIT:
195 ICMP6STAT_INC(icp6s_otime_exceed_transit);
196 return;
197 case ICMP6_TIME_EXCEED_REASSEMBLY:
198 ICMP6STAT_INC(icp6s_otime_exceed_reassembly);
199 return;
200 }
201 break;
202 case ICMP6_PARAM_PROB:
203 switch (code) {
204 case ICMP6_PARAMPROB_HEADER:
205 ICMP6STAT_INC(icp6s_oparamprob_header);
206 return;
207 case ICMP6_PARAMPROB_NEXTHEADER:
208 ICMP6STAT_INC(icp6s_oparamprob_nextheader);
209 return;
210 case ICMP6_PARAMPROB_OPTION:
211 ICMP6STAT_INC(icp6s_oparamprob_option);
212 return;
213 }
214 break;
215 case ND_REDIRECT:
216 ICMP6STAT_INC(icp6s_oredirect);
217 return;
218 }
219 ICMP6STAT_INC(icp6s_ounknown);
220 }
221
222 /*
223 * A wrapper function for icmp6_error() necessary when the erroneous packet
224 * may not contain enough scope zone information.
225 */
226 void
227 icmp6_error2(struct mbuf *m, int type, int code, int param,
228 struct ifnet *ifp)
229 {
230 struct ip6_hdr *ip6;
231
232 if (ifp == NULL)
233 return;
234
235 #ifndef PULLDOWN_TEST
236 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), );
237 #else
238 if (m->m_len < sizeof(struct ip6_hdr)) {
239 m = m_pullup(m, sizeof(struct ip6_hdr));
240 if (m == NULL)
241 return;
242 }
243 #endif
244
245 ip6 = mtod(m, struct ip6_hdr *);
246
247 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0)
248 return;
249 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0)
250 return;
251
252 icmp6_error(m, type, code, param);
253 }
254
255 /*
256 * Generate an error packet of type error in response to bad IP6 packet.
257 */
258 void
259 icmp6_error(struct mbuf *m, int type, int code, int param)
260 {
261 struct ip6_hdr *oip6, *nip6;
262 struct icmp6_hdr *icmp6;
263 u_int preplen;
264 int off;
265 int nxt;
266
267 ICMP6STAT_INC(icp6s_error);
268
269 /* count per-type-code statistics */
270 icmp6_errcount(type, code);
271
272 #ifdef M_DECRYPTED /*not openbsd*/
273 if (m->m_flags & M_DECRYPTED) {
274 ICMP6STAT_INC(icp6s_canterror);
275 goto freeit;
276 }
277 #endif
278
279 #ifndef PULLDOWN_TEST
280 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), );
281 #else
282 if (m->m_len < sizeof(struct ip6_hdr)) {
283 m = m_pullup(m, sizeof(struct ip6_hdr));
284 if (m == NULL)
285 return;
286 }
287 #endif
288 oip6 = mtod(m, struct ip6_hdr *);
289
290 /*
291 * If the destination address of the erroneous packet is a multicast
292 * address, or the packet was sent using link-layer multicast,
293 * we should basically suppress sending an error (RFC 2463, Section
294 * 2.4).
295 * We have two exceptions (the item e.2 in that section):
296 * - the Packet Too Big message can be sent for path MTU discovery.
297 * - the Parameter Problem Message that can be allowed an icmp6 error
298 * in the option type field. This check has been done in
299 * ip6_unknown_opt(), so we can just check the type and code.
300 */
301 if ((m->m_flags & (M_BCAST|M_MCAST) ||
302 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) &&
303 (type != ICMP6_PACKET_TOO_BIG &&
304 (type != ICMP6_PARAM_PROB ||
305 code != ICMP6_PARAMPROB_OPTION)))
306 goto freeit;
307
308 /*
309 * RFC 2463, 2.4 (e.5): source address check.
310 * XXX: the case of anycast source?
311 */
312 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) ||
313 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src))
314 goto freeit;
315
316 /*
317 * If we are about to send ICMPv6 against ICMPv6 error/redirect,
318 * don't do it.
319 */
320 nxt = -1;
321 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
322 if (off >= 0 && nxt == IPPROTO_ICMPV6) {
323 struct icmp6_hdr *icp;
324
325 #ifndef PULLDOWN_TEST
326 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), );
327 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
328 #else
329 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off,
330 sizeof(*icp));
331 if (icp == NULL) {
332 ICMP6STAT_INC(icp6s_tooshort);
333 return;
334 }
335 #endif
336 if (icp->icmp6_type < ICMP6_ECHO_REQUEST ||
337 icp->icmp6_type == ND_REDIRECT) {
338 /*
339 * ICMPv6 error
340 * Special case: for redirect (which is
341 * informational) we must not send icmp6 error.
342 */
343 ICMP6STAT_INC(icp6s_canterror);
344 goto freeit;
345 } else {
346 /* ICMPv6 informational - send the error */
347 }
348 } else {
349 /* non-ICMPv6 - send the error */
350 }
351
352 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */
353
354 /* Finally, do rate limitation check. */
355 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) {
356 ICMP6STAT_INC(icp6s_toofreq);
357 goto freeit;
358 }
359
360 /*
361 * OK, ICMP6 can be generated.
362 */
363
364 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN)
365 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len);
366
367 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
368 M_PREPEND(m, preplen, M_NOWAIT); /* FIB is also copied over. */
369 if (m && m->m_len < preplen)
370 m = m_pullup(m, preplen);
371 if (m == NULL) {
372 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__));
373 return;
374 }
375
376 nip6 = mtod(m, struct ip6_hdr *);
377 nip6->ip6_src = oip6->ip6_src;
378 nip6->ip6_dst = oip6->ip6_dst;
379
380 in6_clearscope(&oip6->ip6_src);
381 in6_clearscope(&oip6->ip6_dst);
382
383 icmp6 = (struct icmp6_hdr *)(nip6 + 1);
384 icmp6->icmp6_type = type;
385 icmp6->icmp6_code = code;
386 icmp6->icmp6_pptr = htonl((u_int32_t)param);
387
388 /*
389 * icmp6_reflect() is designed to be in the input path.
390 * icmp6_error() can be called from both input and output path,
391 * and if we are in output path rcvif could contain bogus value.
392 * clear m->m_pkthdr.rcvif for safety, we should have enough scope
393 * information in ip header (nip6).
394 */
395 m->m_pkthdr.rcvif = NULL;
396
397 ICMP6STAT_INC(icp6s_outhist[type]);
398 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */
399
400 return;
401
402 freeit:
403 /*
404 * If we can't tell whether or not we can generate ICMP6, free it.
405 */
406 m_freem(m);
407 }
408
409 /*
410 * Process a received ICMP6 message.
411 */
412 int
413 icmp6_input(struct mbuf **mp, int *offp, int proto)
414 {
415 struct mbuf *m = *mp, *n;
416 struct ifnet *ifp;
417 struct ip6_hdr *ip6, *nip6;
418 struct icmp6_hdr *icmp6, *nicmp6;
419 int off = *offp;
420 int icmp6len = m->m_pkthdr.len - *offp;
421 int code, sum, noff;
422 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
423 int ip6len, error;
424
425 ifp = m->m_pkthdr.rcvif;
426
427 #ifndef PULLDOWN_TEST
428 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE);
429 /* m might change if M_LOOP. So, call mtod after this */
430 #endif
431
432 /*
433 * Locate icmp6 structure in mbuf, and check
434 * that not corrupted and of at least minimum length
435 */
436
437 ip6 = mtod(m, struct ip6_hdr *);
438 ip6len = sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen);
439 if (icmp6len < sizeof(struct icmp6_hdr)) {
440 ICMP6STAT_INC(icp6s_tooshort);
441 goto freeit;
442 }
443
444 /*
445 * Check multicast group membership.
446 * Note: SSM filters are not applied for ICMPv6 traffic.
447 */
448 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
449 struct in6_multi *inm;
450
451 inm = in6m_lookup(ifp, &ip6->ip6_dst);
452 if (inm == NULL) {
453 IP6STAT_INC(ip6s_notmember);
454 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
455 goto freeit;
456 }
457 }
458
459 /*
460 * calculate the checksum
461 */
462 #ifndef PULLDOWN_TEST
463 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
464 #else
465 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
466 if (icmp6 == NULL) {
467 ICMP6STAT_INC(icp6s_tooshort);
468 return IPPROTO_DONE;
469 }
470 #endif
471 code = icmp6->icmp6_code;
472
473 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) {
474 nd6log((LOG_ERR,
475 "ICMP6 checksum error(%d|%x) %s\n",
476 icmp6->icmp6_type, sum,
477 ip6_sprintf(ip6bufs, &ip6->ip6_src)));
478 ICMP6STAT_INC(icp6s_checksum);
479 goto freeit;
480 }
481
482 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) {
483 /*
484 * Deliver very specific ICMP6 type only.
485 * This is important to deliver TOOBIG. Otherwise PMTUD
486 * will not work.
487 */
488 switch (icmp6->icmp6_type) {
489 case ICMP6_DST_UNREACH:
490 case ICMP6_PACKET_TOO_BIG:
491 case ICMP6_TIME_EXCEEDED:
492 break;
493 default:
494 goto freeit;
495 }
496 }
497
498 ICMP6STAT_INC(icp6s_inhist[icmp6->icmp6_type]);
499 icmp6_ifstat_inc(ifp, ifs6_in_msg);
500 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK)
501 icmp6_ifstat_inc(ifp, ifs6_in_error);
502
503 switch (icmp6->icmp6_type) {
504 case ICMP6_DST_UNREACH:
505 icmp6_ifstat_inc(ifp, ifs6_in_dstunreach);
506 switch (code) {
507 case ICMP6_DST_UNREACH_NOROUTE:
508 code = PRC_UNREACH_NET;
509 break;
510 case ICMP6_DST_UNREACH_ADMIN:
511 icmp6_ifstat_inc(ifp, ifs6_in_adminprohib);
512 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */
513 break;
514 case ICMP6_DST_UNREACH_ADDR:
515 code = PRC_HOSTDEAD;
516 break;
517 case ICMP6_DST_UNREACH_BEYONDSCOPE:
518 /* I mean "source address was incorrect." */
519 code = PRC_PARAMPROB;
520 break;
521 case ICMP6_DST_UNREACH_NOPORT:
522 code = PRC_UNREACH_PORT;
523 break;
524 default:
525 goto badcode;
526 }
527 goto deliver;
528 break;
529
530 case ICMP6_PACKET_TOO_BIG:
531 icmp6_ifstat_inc(ifp, ifs6_in_pkttoobig);
532
533 /* validation is made in icmp6_mtudisc_update */
534
535 code = PRC_MSGSIZE;
536
537 /*
538 * Updating the path MTU will be done after examining
539 * intermediate extension headers.
540 */
541 goto deliver;
542 break;
543
544 case ICMP6_TIME_EXCEEDED:
545 icmp6_ifstat_inc(ifp, ifs6_in_timeexceed);
546 switch (code) {
547 case ICMP6_TIME_EXCEED_TRANSIT:
548 code = PRC_TIMXCEED_INTRANS;
549 break;
550 case ICMP6_TIME_EXCEED_REASSEMBLY:
551 code = PRC_TIMXCEED_REASS;
552 break;
553 default:
554 goto badcode;
555 }
556 goto deliver;
557 break;
558
559 case ICMP6_PARAM_PROB:
560 icmp6_ifstat_inc(ifp, ifs6_in_paramprob);
561 switch (code) {
562 case ICMP6_PARAMPROB_NEXTHEADER:
563 code = PRC_UNREACH_PROTOCOL;
564 break;
565 case ICMP6_PARAMPROB_HEADER:
566 case ICMP6_PARAMPROB_OPTION:
567 code = PRC_PARAMPROB;
568 break;
569 default:
570 goto badcode;
571 }
572 goto deliver;
573 break;
574
575 case ICMP6_ECHO_REQUEST:
576 icmp6_ifstat_inc(ifp, ifs6_in_echo);
577 if (code != 0)
578 goto badcode;
579 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) {
580 /* Give up remote */
581 break;
582 }
583 if ((n->m_flags & M_EXT) != 0
584 || n->m_len < off + sizeof(struct icmp6_hdr)) {
585 struct mbuf *n0 = n;
586 int n0len;
587
588 CTASSERT(sizeof(*nip6) + sizeof(*nicmp6) <= MHLEN);
589 n = m_gethdr(M_NOWAIT, n0->m_type);
590 if (n == NULL) {
591 /* Give up remote */
592 m_freem(n0);
593 break;
594 }
595
596 m_move_pkthdr(n, n0); /* FIB copied. */
597 n0len = n0->m_pkthdr.len; /* save for use below */
598 /*
599 * Copy IPv6 and ICMPv6 only.
600 */
601 nip6 = mtod(n, struct ip6_hdr *);
602 bcopy(ip6, nip6, sizeof(struct ip6_hdr));
603 nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
604 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
605 noff = sizeof(struct ip6_hdr);
606 /* new mbuf contains only ipv6+icmpv6 headers */
607 n->m_len = noff + sizeof(struct icmp6_hdr);
608 /*
609 * Adjust mbuf. ip6_plen will be adjusted in
610 * ip6_output().
611 */
612 m_adj(n0, off + sizeof(struct icmp6_hdr));
613 /* recalculate complete packet size */
614 n->m_pkthdr.len = n0len + (noff - off);
615 n->m_next = n0;
616 } else {
617 nip6 = mtod(n, struct ip6_hdr *);
618 IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off,
619 sizeof(*nicmp6));
620 noff = off;
621 }
622 nicmp6->icmp6_type = ICMP6_ECHO_REPLY;
623 nicmp6->icmp6_code = 0;
624 if (n) {
625 ICMP6STAT_INC(icp6s_reflect);
626 ICMP6STAT_INC(icp6s_outhist[ICMP6_ECHO_REPLY]);
627 icmp6_reflect(n, noff);
628 }
629 break;
630
631 case ICMP6_ECHO_REPLY:
632 icmp6_ifstat_inc(ifp, ifs6_in_echoreply);
633 if (code != 0)
634 goto badcode;
635 break;
636
637 case MLD_LISTENER_QUERY:
638 case MLD_LISTENER_REPORT:
639 case MLD_LISTENER_DONE:
640 case MLDV2_LISTENER_REPORT:
641 /*
642 * Drop MLD traffic which is not link-local, has a hop limit
643 * of greater than 1 hop, or which does not have the
644 * IPv6 HBH Router Alert option.
645 * As IPv6 HBH options are stripped in ip6_input() we must
646 * check an mbuf header flag.
647 * XXX Should we also sanity check that these messages
648 * were directed to a link-local multicast prefix?
649 */
650 if ((ip6->ip6_hlim != 1) || (m->m_flags & M_RTALERT_MLD) == 0)
651 goto freeit;
652 if (mld_input(m, off, icmp6len) != 0)
653 return (IPPROTO_DONE);
654 /* m stays. */
655 break;
656
657 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */
658 {
659 enum { WRU, FQDN } mode;
660
661 if (!V_icmp6_nodeinfo)
662 break;
663
664 if (icmp6len == sizeof(struct icmp6_hdr) + 4)
665 mode = WRU;
666 else if (icmp6len >= sizeof(struct icmp6_nodeinfo))
667 mode = FQDN;
668 else
669 goto badlen;
670
671 if (mode == FQDN) {
672 #ifndef PULLDOWN_TEST
673 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo),
674 IPPROTO_DONE);
675 #endif
676 n = m_copy(m, 0, M_COPYALL);
677 if (n)
678 n = ni6_input(n, off);
679 /* XXX meaningless if n == NULL */
680 noff = sizeof(struct ip6_hdr);
681 } else {
682 struct prison *pr;
683 u_char *p;
684 int maxhlen, hlen;
685
686 /*
687 * XXX: this combination of flags is pointless,
688 * but should we keep this for compatibility?
689 */
690 if ((V_icmp6_nodeinfo & 5) != 5)
691 break;
692
693 if (code != 0)
694 goto badcode;
695
696 CTASSERT(sizeof(*nip6) + sizeof(*nicmp6) + 4 <= MHLEN);
697 n = m_gethdr(M_NOWAIT, m->m_type);
698 if (n == NULL) {
699 /* Give up remote */
700 break;
701 }
702 if (!m_dup_pkthdr(n, m, M_NOWAIT)) {
703 /*
704 * Previous code did a blind M_COPY_PKTHDR
705 * and said "just for rcvif". If true, then
706 * we could tolerate the dup failing (due to
707 * the deep copy of the tag chain). For now
708 * be conservative and just fail.
709 */
710 m_free(n);
711 n = NULL;
712 }
713 maxhlen = M_TRAILINGSPACE(n) -
714 (sizeof(*nip6) + sizeof(*nicmp6) + 4);
715 pr = curthread->td_ucred->cr_prison;
716 mtx_lock(&pr->pr_mtx);
717 hlen = strlen(pr->pr_hostname);
718 if (maxhlen > hlen)
719 maxhlen = hlen;
720 /*
721 * Copy IPv6 and ICMPv6 only.
722 */
723 nip6 = mtod(n, struct ip6_hdr *);
724 bcopy(ip6, nip6, sizeof(struct ip6_hdr));
725 nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
726 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
727 p = (u_char *)(nicmp6 + 1);
728 bzero(p, 4);
729 /* meaningless TTL */
730 bcopy(pr->pr_hostname, p + 4, maxhlen);
731 mtx_unlock(&pr->pr_mtx);
732 noff = sizeof(struct ip6_hdr);
733 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
734 sizeof(struct icmp6_hdr) + 4 + maxhlen;
735 nicmp6->icmp6_type = ICMP6_WRUREPLY;
736 nicmp6->icmp6_code = 0;
737 }
738 if (n) {
739 ICMP6STAT_INC(icp6s_reflect);
740 ICMP6STAT_INC(icp6s_outhist[ICMP6_WRUREPLY]);
741 icmp6_reflect(n, noff);
742 }
743 break;
744 }
745
746 case ICMP6_WRUREPLY:
747 if (code != 0)
748 goto badcode;
749 break;
750
751 case ND_ROUTER_SOLICIT:
752 icmp6_ifstat_inc(ifp, ifs6_in_routersolicit);
753 if (code != 0)
754 goto badcode;
755 if (icmp6len < sizeof(struct nd_router_solicit))
756 goto badlen;
757 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
758 /* give up local */
759
760 /* Send incoming SeND packet to user space. */
761 if (send_sendso_input_hook != NULL) {
762 IP6_EXTHDR_CHECK(m, off,
763 icmp6len, IPPROTO_DONE);
764 error = send_sendso_input_hook(m, ifp,
765 SND_IN, ip6len);
766 /* -1 == no app on SEND socket */
767 if (error == 0)
768 return (IPPROTO_DONE);
769 nd6_rs_input(m, off, icmp6len);
770 } else
771 nd6_rs_input(m, off, icmp6len);
772 m = NULL;
773 goto freeit;
774 }
775 if (send_sendso_input_hook != NULL) {
776 IP6_EXTHDR_CHECK(n, off,
777 icmp6len, IPPROTO_DONE);
778 error = send_sendso_input_hook(n, ifp,
779 SND_IN, ip6len);
780 if (error == 0)
781 goto freeit;
782 /* -1 == no app on SEND socket */
783 nd6_rs_input(n, off, icmp6len);
784 } else
785 nd6_rs_input(n, off, icmp6len);
786 /* m stays. */
787 break;
788
789 case ND_ROUTER_ADVERT:
790 icmp6_ifstat_inc(ifp, ifs6_in_routeradvert);
791 if (code != 0)
792 goto badcode;
793 if (icmp6len < sizeof(struct nd_router_advert))
794 goto badlen;
795 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
796
797 /* Send incoming SeND-protected/ND packet to user space. */
798 if (send_sendso_input_hook != NULL) {
799 error = send_sendso_input_hook(m, ifp,
800 SND_IN, ip6len);
801 if (error == 0)
802 return (IPPROTO_DONE);
803 nd6_ra_input(m, off, icmp6len);
804 } else
805 nd6_ra_input(m, off, icmp6len);
806 m = NULL;
807 goto freeit;
808 }
809 if (send_sendso_input_hook != NULL) {
810 error = send_sendso_input_hook(n, ifp,
811 SND_IN, ip6len);
812 if (error == 0)
813 goto freeit;
814 nd6_ra_input(n, off, icmp6len);
815 } else
816 nd6_ra_input(n, off, icmp6len);
817 /* m stays. */
818 break;
819
820 case ND_NEIGHBOR_SOLICIT:
821 icmp6_ifstat_inc(ifp, ifs6_in_neighborsolicit);
822 if (code != 0)
823 goto badcode;
824 if (icmp6len < sizeof(struct nd_neighbor_solicit))
825 goto badlen;
826 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
827 if (send_sendso_input_hook != NULL) {
828 error = send_sendso_input_hook(m, ifp,
829 SND_IN, ip6len);
830 if (error == 0)
831 return (IPPROTO_DONE);
832 nd6_ns_input(m, off, icmp6len);
833 } else
834 nd6_ns_input(m, off, icmp6len);
835 m = NULL;
836 goto freeit;
837 }
838 if (send_sendso_input_hook != NULL) {
839 error = send_sendso_input_hook(n, ifp,
840 SND_IN, ip6len);
841 if (error == 0)
842 goto freeit;
843 nd6_ns_input(n, off, icmp6len);
844 } else
845 nd6_ns_input(n, off, icmp6len);
846 /* m stays. */
847 break;
848
849 case ND_NEIGHBOR_ADVERT:
850 icmp6_ifstat_inc(ifp, ifs6_in_neighboradvert);
851 if (code != 0)
852 goto badcode;
853 if (icmp6len < sizeof(struct nd_neighbor_advert))
854 goto badlen;
855 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
856
857 /* Send incoming SeND-protected/ND packet to user space. */
858 if (send_sendso_input_hook != NULL) {
859 error = send_sendso_input_hook(m, ifp,
860 SND_IN, ip6len);
861 if (error == 0)
862 return (IPPROTO_DONE);
863 nd6_na_input(m, off, icmp6len);
864 } else
865 nd6_na_input(m, off, icmp6len);
866 m = NULL;
867 goto freeit;
868 }
869 if (send_sendso_input_hook != NULL) {
870 error = send_sendso_input_hook(n, ifp,
871 SND_IN, ip6len);
872 if (error == 0)
873 goto freeit;
874 nd6_na_input(n, off, icmp6len);
875 } else
876 nd6_na_input(n, off, icmp6len);
877 /* m stays. */
878 break;
879
880 case ND_REDIRECT:
881 icmp6_ifstat_inc(ifp, ifs6_in_redirect);
882 if (code != 0)
883 goto badcode;
884 if (icmp6len < sizeof(struct nd_redirect))
885 goto badlen;
886 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
887 if (send_sendso_input_hook != NULL) {
888 error = send_sendso_input_hook(m, ifp,
889 SND_IN, ip6len);
890 if (error == 0)
891 return (IPPROTO_DONE);
892 icmp6_redirect_input(m, off);
893 } else
894 icmp6_redirect_input(m, off);
895 m = NULL;
896 goto freeit;
897 }
898 if (send_sendso_input_hook != NULL) {
899 error = send_sendso_input_hook(n, ifp,
900 SND_IN, ip6len);
901 if (error == 0)
902 goto freeit;
903 icmp6_redirect_input(n, off);
904 } else
905 icmp6_redirect_input(n, off);
906 /* m stays. */
907 break;
908
909 case ICMP6_ROUTER_RENUMBERING:
910 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND &&
911 code != ICMP6_ROUTER_RENUMBERING_RESULT)
912 goto badcode;
913 if (icmp6len < sizeof(struct icmp6_router_renum))
914 goto badlen;
915 break;
916
917 default:
918 nd6log((LOG_DEBUG,
919 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n",
920 icmp6->icmp6_type, ip6_sprintf(ip6bufs, &ip6->ip6_src),
921 ip6_sprintf(ip6bufd, &ip6->ip6_dst),
922 ifp ? ifp->if_index : 0));
923 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) {
924 /* ICMPv6 error: MUST deliver it by spec... */
925 code = PRC_NCMDS;
926 /* deliver */
927 } else {
928 /* ICMPv6 informational: MUST not deliver */
929 break;
930 }
931 deliver:
932 if (icmp6_notify_error(&m, off, icmp6len, code) != 0) {
933 /* In this case, m should've been freed. */
934 return (IPPROTO_DONE);
935 }
936 break;
937
938 badcode:
939 ICMP6STAT_INC(icp6s_badcode);
940 break;
941
942 badlen:
943 ICMP6STAT_INC(icp6s_badlen);
944 break;
945 }
946
947 /* deliver the packet to appropriate sockets */
948 icmp6_rip6_input(&m, *offp);
949
950 return IPPROTO_DONE;
951
952 freeit:
953 m_freem(m);
954 return IPPROTO_DONE;
955 }
956
957 static int
958 icmp6_notify_error(struct mbuf **mp, int off, int icmp6len, int code)
959 {
960 struct mbuf *m = *mp;
961 struct icmp6_hdr *icmp6;
962 struct ip6_hdr *eip6;
963 u_int32_t notifymtu;
964 struct sockaddr_in6 icmp6src, icmp6dst;
965
966 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) {
967 ICMP6STAT_INC(icp6s_tooshort);
968 goto freeit;
969 }
970 #ifndef PULLDOWN_TEST
971 IP6_EXTHDR_CHECK(m, off,
972 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1);
973 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
974 #else
975 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
976 sizeof(*icmp6) + sizeof(struct ip6_hdr));
977 if (icmp6 == NULL) {
978 ICMP6STAT_INC(icp6s_tooshort);
979 return (-1);
980 }
981 #endif
982 eip6 = (struct ip6_hdr *)(icmp6 + 1);
983
984 /* Detect the upper level protocol */
985 {
986 void (*ctlfunc)(int, struct sockaddr *, void *);
987 u_int8_t nxt = eip6->ip6_nxt;
988 int eoff = off + sizeof(struct icmp6_hdr) +
989 sizeof(struct ip6_hdr);
990 struct ip6ctlparam ip6cp;
991 struct in6_addr *finaldst = NULL;
992 int icmp6type = icmp6->icmp6_type;
993 struct ip6_frag *fh;
994 struct ip6_rthdr *rth;
995 struct ip6_rthdr0 *rth0;
996 int rthlen;
997
998 while (1) { /* XXX: should avoid infinite loop explicitly? */
999 struct ip6_ext *eh;
1000
1001 switch (nxt) {
1002 case IPPROTO_HOPOPTS:
1003 case IPPROTO_DSTOPTS:
1004 case IPPROTO_AH:
1005 #ifndef PULLDOWN_TEST
1006 IP6_EXTHDR_CHECK(m, 0,
1007 eoff + sizeof(struct ip6_ext), -1);
1008 eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff);
1009 #else
1010 IP6_EXTHDR_GET(eh, struct ip6_ext *, m,
1011 eoff, sizeof(*eh));
1012 if (eh == NULL) {
1013 ICMP6STAT_INC(icp6s_tooshort);
1014 return (-1);
1015 }
1016 #endif
1017
1018 if (nxt == IPPROTO_AH)
1019 eoff += (eh->ip6e_len + 2) << 2;
1020 else
1021 eoff += (eh->ip6e_len + 1) << 3;
1022 nxt = eh->ip6e_nxt;
1023 break;
1024 case IPPROTO_ROUTING:
1025 /*
1026 * When the erroneous packet contains a
1027 * routing header, we should examine the
1028 * header to determine the final destination.
1029 * Otherwise, we can't properly update
1030 * information that depends on the final
1031 * destination (e.g. path MTU).
1032 */
1033 #ifndef PULLDOWN_TEST
1034 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1);
1035 rth = (struct ip6_rthdr *)
1036 (mtod(m, caddr_t) + eoff);
1037 #else
1038 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m,
1039 eoff, sizeof(*rth));
1040 if (rth == NULL) {
1041 ICMP6STAT_INC(icp6s_tooshort);
1042 return (-1);
1043 }
1044 #endif
1045 rthlen = (rth->ip6r_len + 1) << 3;
1046 /*
1047 * XXX: currently there is no
1048 * officially defined type other
1049 * than type-0.
1050 * Note that if the segment left field
1051 * is 0, all intermediate hops must
1052 * have been passed.
1053 */
1054 if (rth->ip6r_segleft &&
1055 rth->ip6r_type == IPV6_RTHDR_TYPE_0) {
1056 int hops;
1057
1058 #ifndef PULLDOWN_TEST
1059 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1);
1060 rth0 = (struct ip6_rthdr0 *)
1061 (mtod(m, caddr_t) + eoff);
1062 #else
1063 IP6_EXTHDR_GET(rth0,
1064 struct ip6_rthdr0 *, m,
1065 eoff, rthlen);
1066 if (rth0 == NULL) {
1067 ICMP6STAT_INC(icp6s_tooshort);
1068 return (-1);
1069 }
1070 #endif
1071 /* just ignore a bogus header */
1072 if ((rth0->ip6r0_len % 2) == 0 &&
1073 (hops = rth0->ip6r0_len/2))
1074 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1);
1075 }
1076 eoff += rthlen;
1077 nxt = rth->ip6r_nxt;
1078 break;
1079 case IPPROTO_FRAGMENT:
1080 #ifndef PULLDOWN_TEST
1081 IP6_EXTHDR_CHECK(m, 0, eoff +
1082 sizeof(struct ip6_frag), -1);
1083 fh = (struct ip6_frag *)(mtod(m, caddr_t) +
1084 eoff);
1085 #else
1086 IP6_EXTHDR_GET(fh, struct ip6_frag *, m,
1087 eoff, sizeof(*fh));
1088 if (fh == NULL) {
1089 ICMP6STAT_INC(icp6s_tooshort);
1090 return (-1);
1091 }
1092 #endif
1093 /*
1094 * Data after a fragment header is meaningless
1095 * unless it is the first fragment, but
1096 * we'll go to the notify label for path MTU
1097 * discovery.
1098 */
1099 if (fh->ip6f_offlg & IP6F_OFF_MASK)
1100 goto notify;
1101
1102 eoff += sizeof(struct ip6_frag);
1103 nxt = fh->ip6f_nxt;
1104 break;
1105 default:
1106 /*
1107 * This case includes ESP and the No Next
1108 * Header. In such cases going to the notify
1109 * label does not have any meaning
1110 * (i.e. ctlfunc will be NULL), but we go
1111 * anyway since we might have to update
1112 * path MTU information.
1113 */
1114 goto notify;
1115 }
1116 }
1117 notify:
1118 #ifndef PULLDOWN_TEST
1119 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
1120 #else
1121 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
1122 sizeof(*icmp6) + sizeof(struct ip6_hdr));
1123 if (icmp6 == NULL) {
1124 ICMP6STAT_INC(icp6s_tooshort);
1125 return (-1);
1126 }
1127 #endif
1128
1129 /*
1130 * retrieve parameters from the inner IPv6 header, and convert
1131 * them into sockaddr structures.
1132 * XXX: there is no guarantee that the source or destination
1133 * addresses of the inner packet are in the same scope as
1134 * the addresses of the icmp packet. But there is no other
1135 * way to determine the zone.
1136 */
1137 eip6 = (struct ip6_hdr *)(icmp6 + 1);
1138
1139 bzero(&icmp6dst, sizeof(icmp6dst));
1140 icmp6dst.sin6_len = sizeof(struct sockaddr_in6);
1141 icmp6dst.sin6_family = AF_INET6;
1142 if (finaldst == NULL)
1143 icmp6dst.sin6_addr = eip6->ip6_dst;
1144 else
1145 icmp6dst.sin6_addr = *finaldst;
1146 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL))
1147 goto freeit;
1148 bzero(&icmp6src, sizeof(icmp6src));
1149 icmp6src.sin6_len = sizeof(struct sockaddr_in6);
1150 icmp6src.sin6_family = AF_INET6;
1151 icmp6src.sin6_addr = eip6->ip6_src;
1152 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL))
1153 goto freeit;
1154 icmp6src.sin6_flowinfo =
1155 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK);
1156
1157 if (finaldst == NULL)
1158 finaldst = &eip6->ip6_dst;
1159 ip6cp.ip6c_m = m;
1160 ip6cp.ip6c_icmp6 = icmp6;
1161 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1);
1162 ip6cp.ip6c_off = eoff;
1163 ip6cp.ip6c_finaldst = finaldst;
1164 ip6cp.ip6c_src = &icmp6src;
1165 ip6cp.ip6c_nxt = nxt;
1166
1167 if (icmp6type == ICMP6_PACKET_TOO_BIG) {
1168 notifymtu = ntohl(icmp6->icmp6_mtu);
1169 ip6cp.ip6c_cmdarg = (void *)¬ifymtu;
1170 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/
1171 }
1172
1173 ctlfunc = (void (*)(int, struct sockaddr *, void *))
1174 (inet6sw[ip6_protox[nxt]].pr_ctlinput);
1175 if (ctlfunc) {
1176 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst,
1177 &ip6cp);
1178 }
1179 }
1180 *mp = m;
1181 return (0);
1182
1183 freeit:
1184 m_freem(m);
1185 return (-1);
1186 }
1187
1188 void
1189 icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated)
1190 {
1191 struct in6_addr *dst = ip6cp->ip6c_finaldst;
1192 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6;
1193 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */
1194 u_int mtu = ntohl(icmp6->icmp6_mtu);
1195 struct in_conninfo inc;
1196
1197 #if 0
1198 /*
1199 * RFC2460 section 5, last paragraph.
1200 * even though minimum link MTU for IPv6 is IPV6_MMTU,
1201 * we may see ICMPv6 too big with mtu < IPV6_MMTU
1202 * due to packet translator in the middle.
1203 * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for
1204 * special handling.
1205 */
1206 if (mtu < IPV6_MMTU)
1207 return;
1208 #endif
1209
1210 /*
1211 * we reject ICMPv6 too big with abnormally small value.
1212 * XXX what is the good definition of "abnormally small"?
1213 */
1214 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8)
1215 return;
1216
1217 if (!validated)
1218 return;
1219
1220 /*
1221 * In case the suggested mtu is less than IPV6_MMTU, we
1222 * only need to remember that it was for above mentioned
1223 * "alwaysfrag" case.
1224 * Try to be as close to the spec as possible.
1225 */
1226 if (mtu < IPV6_MMTU)
1227 mtu = IPV6_MMTU - 8;
1228
1229 bzero(&inc, sizeof(inc));
1230 inc.inc_fibnum = M_GETFIB(m);
1231 inc.inc_flags |= INC_ISIPV6;
1232 inc.inc6_faddr = *dst;
1233 if (in6_setscope(&inc.inc6_faddr, m->m_pkthdr.rcvif, NULL))
1234 return;
1235
1236 if (mtu < tcp_maxmtu6(&inc, NULL)) {
1237 tcp_hc_updatemtu(&inc, mtu);
1238 ICMP6STAT_INC(icp6s_pmtuchg);
1239 }
1240 }
1241
1242 /*
1243 * Process a Node Information Query packet, based on
1244 * draft-ietf-ipngwg-icmp-name-lookups-07.
1245 *
1246 * Spec incompatibilities:
1247 * - IPv6 Subject address handling
1248 * - IPv4 Subject address handling support missing
1249 * - Proxy reply (answer even if it's not for me)
1250 * - joins NI group address at in6_ifattach() time only, does not cope
1251 * with hostname changes by sethostname(3)
1252 */
1253 static struct mbuf *
1254 ni6_input(struct mbuf *m, int off)
1255 {
1256 struct icmp6_nodeinfo *ni6, *nni6;
1257 struct mbuf *n = NULL;
1258 struct prison *pr;
1259 u_int16_t qtype;
1260 int subjlen;
1261 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
1262 struct ni_reply_fqdn *fqdn;
1263 int addrs; /* for NI_QTYPE_NODEADDR */
1264 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */
1265 struct in6_addr in6_subj; /* subject address */
1266 struct ip6_hdr *ip6;
1267 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */
1268 char *subj = NULL;
1269 struct in6_ifaddr *ia6 = NULL;
1270
1271 ip6 = mtod(m, struct ip6_hdr *);
1272 #ifndef PULLDOWN_TEST
1273 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off);
1274 #else
1275 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6));
1276 if (ni6 == NULL) {
1277 /* m is already reclaimed */
1278 return (NULL);
1279 }
1280 #endif
1281
1282 /*
1283 * Validate IPv6 source address.
1284 * The default configuration MUST be to refuse answering queries from
1285 * global-scope addresses according to RFC4602.
1286 * Notes:
1287 * - it's not very clear what "refuse" means; this implementation
1288 * simply drops it.
1289 * - it's not very easy to identify global-scope (unicast) addresses
1290 * since there are many prefixes for them. It should be safer
1291 * and in practice sufficient to check "all" but loopback and
1292 * link-local (note that site-local unicast was deprecated and
1293 * ULA is defined as global scope-wise)
1294 */
1295 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_GLOBALOK) == 0 &&
1296 !IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) &&
1297 !IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src))
1298 goto bad;
1299
1300 /*
1301 * Validate IPv6 destination address.
1302 *
1303 * The Responder must discard the Query without further processing
1304 * unless it is one of the Responder's unicast or anycast addresses, or
1305 * a link-local scope multicast address which the Responder has joined.
1306 * [RFC4602, Section 5.]
1307 */
1308 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
1309 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst))
1310 goto bad;
1311 /* else it's a link-local multicast, fine */
1312 } else { /* unicast or anycast */
1313 if ((ia6 = ip6_getdstifaddr(m)) == NULL)
1314 goto bad; /* XXX impossible */
1315
1316 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) &&
1317 !(V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK)) {
1318 ifa_free(&ia6->ia_ifa);
1319 nd6log((LOG_DEBUG, "ni6_input: ignore node info to "
1320 "a temporary address in %s:%d",
1321 __FILE__, __LINE__));
1322 goto bad;
1323 }
1324 ifa_free(&ia6->ia_ifa);
1325 }
1326
1327 /* validate query Subject field. */
1328 qtype = ntohs(ni6->ni_qtype);
1329 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo);
1330 switch (qtype) {
1331 case NI_QTYPE_NOOP:
1332 case NI_QTYPE_SUPTYPES:
1333 /* 07 draft */
1334 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0)
1335 break;
1336 /* FALLTHROUGH */
1337 case NI_QTYPE_FQDN:
1338 case NI_QTYPE_NODEADDR:
1339 case NI_QTYPE_IPV4ADDR:
1340 switch (ni6->ni_code) {
1341 case ICMP6_NI_SUBJ_IPV6:
1342 #if ICMP6_NI_SUBJ_IPV6 != 0
1343 case 0:
1344 #endif
1345 /*
1346 * backward compatibility - try to accept 03 draft
1347 * format, where no Subject is present.
1348 */
1349 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 &&
1350 subjlen == 0) {
1351 oldfqdn++;
1352 break;
1353 }
1354 #if ICMP6_NI_SUBJ_IPV6 != 0
1355 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6)
1356 goto bad;
1357 #endif
1358
1359 if (subjlen != sizeof(struct in6_addr))
1360 goto bad;
1361
1362 /*
1363 * Validate Subject address.
1364 *
1365 * Not sure what exactly "address belongs to the node"
1366 * means in the spec, is it just unicast, or what?
1367 *
1368 * At this moment we consider Subject address as
1369 * "belong to the node" if the Subject address equals
1370 * to the IPv6 destination address; validation for
1371 * IPv6 destination address should have done enough
1372 * check for us.
1373 *
1374 * We do not do proxy at this moment.
1375 */
1376 /* m_pulldown instead of copy? */
1377 m_copydata(m, off + sizeof(struct icmp6_nodeinfo),
1378 subjlen, (caddr_t)&in6_subj);
1379 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL))
1380 goto bad;
1381
1382 subj = (char *)&in6_subj;
1383 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj))
1384 break;
1385
1386 /*
1387 * XXX if we are to allow other cases, we should really
1388 * be careful about scope here.
1389 * basically, we should disallow queries toward IPv6
1390 * destination X with subject Y,
1391 * if scope(X) > scope(Y).
1392 * if we allow scope(X) > scope(Y), it will result in
1393 * information leakage across scope boundary.
1394 */
1395 goto bad;
1396
1397 case ICMP6_NI_SUBJ_FQDN:
1398 /*
1399 * Validate Subject name with gethostname(3).
1400 *
1401 * The behavior may need some debate, since:
1402 * - we are not sure if the node has FQDN as
1403 * hostname (returned by gethostname(3)).
1404 * - the code does wildcard match for truncated names.
1405 * however, we are not sure if we want to perform
1406 * wildcard match, if gethostname(3) side has
1407 * truncated hostname.
1408 */
1409 pr = curthread->td_ucred->cr_prison;
1410 mtx_lock(&pr->pr_mtx);
1411 n = ni6_nametodns(pr->pr_hostname,
1412 strlen(pr->pr_hostname), 0);
1413 mtx_unlock(&pr->pr_mtx);
1414 if (!n || n->m_next || n->m_len == 0)
1415 goto bad;
1416 IP6_EXTHDR_GET(subj, char *, m,
1417 off + sizeof(struct icmp6_nodeinfo), subjlen);
1418 if (subj == NULL)
1419 goto bad;
1420 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *),
1421 n->m_len)) {
1422 goto bad;
1423 }
1424 m_freem(n);
1425 n = NULL;
1426 break;
1427
1428 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */
1429 default:
1430 goto bad;
1431 }
1432 break;
1433 }
1434
1435 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */
1436 switch (qtype) {
1437 case NI_QTYPE_FQDN:
1438 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_FQDNOK) == 0)
1439 goto bad;
1440 break;
1441 case NI_QTYPE_NODEADDR:
1442 case NI_QTYPE_IPV4ADDR:
1443 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_NODEADDROK) == 0)
1444 goto bad;
1445 break;
1446 }
1447
1448 /* guess reply length */
1449 switch (qtype) {
1450 case NI_QTYPE_NOOP:
1451 break; /* no reply data */
1452 case NI_QTYPE_SUPTYPES:
1453 replylen += sizeof(u_int32_t);
1454 break;
1455 case NI_QTYPE_FQDN:
1456 /* XXX will append an mbuf */
1457 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1458 break;
1459 case NI_QTYPE_NODEADDR:
1460 addrs = ni6_addrs(ni6, m, &ifp, (struct in6_addr *)subj);
1461 if ((replylen += addrs * (sizeof(struct in6_addr) +
1462 sizeof(u_int32_t))) > MCLBYTES)
1463 replylen = MCLBYTES; /* XXX: will truncate pkt later */
1464 break;
1465 case NI_QTYPE_IPV4ADDR:
1466 /* unsupported - should respond with unknown Qtype? */
1467 break;
1468 default:
1469 /*
1470 * XXX: We must return a reply with the ICMP6 code
1471 * `unknown Qtype' in this case. However we regard the case
1472 * as an FQDN query for backward compatibility.
1473 * Older versions set a random value to this field,
1474 * so it rarely varies in the defined qtypes.
1475 * But the mechanism is not reliable...
1476 * maybe we should obsolete older versions.
1477 */
1478 qtype = NI_QTYPE_FQDN;
1479 /* XXX will append an mbuf */
1480 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1481 oldfqdn++;
1482 break;
1483 }
1484
1485 /* Allocate an mbuf to reply. */
1486 if (replylen > MCLBYTES) {
1487 /*
1488 * XXX: should we try to allocate more? But MCLBYTES
1489 * is probably much larger than IPV6_MMTU...
1490 */
1491 goto bad;
1492 }
1493 if (replylen > MHLEN)
1494 n = m_getcl(M_NOWAIT, m->m_type, M_PKTHDR);
1495 else
1496 n = m_gethdr(M_NOWAIT, m->m_type);
1497 if (n == NULL) {
1498 m_freem(m);
1499 return (NULL);
1500 }
1501 m_move_pkthdr(n, m); /* just for recvif and FIB */
1502 n->m_pkthdr.len = n->m_len = replylen;
1503
1504 /* copy mbuf header and IPv6 + Node Information base headers */
1505 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr));
1506 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1);
1507 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo));
1508
1509 /* qtype dependent procedure */
1510 switch (qtype) {
1511 case NI_QTYPE_NOOP:
1512 nni6->ni_code = ICMP6_NI_SUCCESS;
1513 nni6->ni_flags = 0;
1514 break;
1515 case NI_QTYPE_SUPTYPES:
1516 {
1517 u_int32_t v;
1518 nni6->ni_code = ICMP6_NI_SUCCESS;
1519 nni6->ni_flags = htons(0x0000); /* raw bitmap */
1520 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */
1521 v = (u_int32_t)htonl(0x0000000f);
1522 bcopy(&v, nni6 + 1, sizeof(u_int32_t));
1523 break;
1524 }
1525 case NI_QTYPE_FQDN:
1526 nni6->ni_code = ICMP6_NI_SUCCESS;
1527 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) +
1528 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo));
1529 nni6->ni_flags = 0; /* XXX: meaningless TTL */
1530 fqdn->ni_fqdn_ttl = 0; /* ditto. */
1531 /*
1532 * XXX do we really have FQDN in hostname?
1533 */
1534 pr = curthread->td_ucred->cr_prison;
1535 mtx_lock(&pr->pr_mtx);
1536 n->m_next = ni6_nametodns(pr->pr_hostname,
1537 strlen(pr->pr_hostname), oldfqdn);
1538 mtx_unlock(&pr->pr_mtx);
1539 if (n->m_next == NULL)
1540 goto bad;
1541 /* XXX we assume that n->m_next is not a chain */
1542 if (n->m_next->m_next != NULL)
1543 goto bad;
1544 n->m_pkthdr.len += n->m_next->m_len;
1545 break;
1546 case NI_QTYPE_NODEADDR:
1547 {
1548 int lenlim, copied;
1549
1550 nni6->ni_code = ICMP6_NI_SUCCESS;
1551 n->m_pkthdr.len = n->m_len =
1552 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
1553 lenlim = M_TRAILINGSPACE(n);
1554 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim);
1555 /* XXX: reset mbuf length */
1556 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
1557 sizeof(struct icmp6_nodeinfo) + copied;
1558 break;
1559 }
1560 default:
1561 break; /* XXX impossible! */
1562 }
1563
1564 nni6->ni_type = ICMP6_NI_REPLY;
1565 m_freem(m);
1566 return (n);
1567
1568 bad:
1569 m_freem(m);
1570 if (n)
1571 m_freem(n);
1572 return (NULL);
1573 }
1574
1575 /*
1576 * make a mbuf with DNS-encoded string. no compression support.
1577 *
1578 * XXX names with less than 2 dots (like "foo" or "foo.section") will be
1579 * treated as truncated name (two \0 at the end). this is a wild guess.
1580 *
1581 * old - return pascal string if non-zero
1582 */
1583 static struct mbuf *
1584 ni6_nametodns(const char *name, int namelen, int old)
1585 {
1586 struct mbuf *m;
1587 char *cp, *ep;
1588 const char *p, *q;
1589 int i, len, nterm;
1590
1591 if (old)
1592 len = namelen + 1;
1593 else
1594 len = MCLBYTES;
1595
1596 /* Because MAXHOSTNAMELEN is usually 256, we use cluster mbuf. */
1597 if (len > MLEN)
1598 m = m_getcl(M_NOWAIT, MT_DATA, 0);
1599 else
1600 m = m_get(M_NOWAIT, MT_DATA);
1601 if (m == NULL)
1602 goto fail;
1603
1604 if (old) {
1605 m->m_len = len;
1606 *mtod(m, char *) = namelen;
1607 bcopy(name, mtod(m, char *) + 1, namelen);
1608 return m;
1609 } else {
1610 m->m_len = 0;
1611 cp = mtod(m, char *);
1612 ep = mtod(m, char *) + M_TRAILINGSPACE(m);
1613
1614 /* if not certain about my name, return empty buffer */
1615 if (namelen == 0)
1616 return m;
1617
1618 /*
1619 * guess if it looks like shortened hostname, or FQDN.
1620 * shortened hostname needs two trailing "\0".
1621 */
1622 i = 0;
1623 for (p = name; p < name + namelen; p++) {
1624 if (*p && *p == '.')
1625 i++;
1626 }
1627 if (i < 2)
1628 nterm = 2;
1629 else
1630 nterm = 1;
1631
1632 p = name;
1633 while (cp < ep && p < name + namelen) {
1634 i = 0;
1635 for (q = p; q < name + namelen && *q && *q != '.'; q++)
1636 i++;
1637 /* result does not fit into mbuf */
1638 if (cp + i + 1 >= ep)
1639 goto fail;
1640 /*
1641 * DNS label length restriction, RFC1035 page 8.
1642 * "i == 0" case is included here to avoid returning
1643 * 0-length label on "foo..bar".
1644 */
1645 if (i <= 0 || i >= 64)
1646 goto fail;
1647 *cp++ = i;
1648 bcopy(p, cp, i);
1649 cp += i;
1650 p = q;
1651 if (p < name + namelen && *p == '.')
1652 p++;
1653 }
1654 /* termination */
1655 if (cp + nterm >= ep)
1656 goto fail;
1657 while (nterm-- > 0)
1658 *cp++ = '\0';
1659 m->m_len = cp - mtod(m, char *);
1660 return m;
1661 }
1662
1663 panic("should not reach here");
1664 /* NOTREACHED */
1665
1666 fail:
1667 if (m)
1668 m_freem(m);
1669 return NULL;
1670 }
1671
1672 /*
1673 * check if two DNS-encoded string matches. takes care of truncated
1674 * form (with \0\0 at the end). no compression support.
1675 * XXX upper/lowercase match (see RFC2065)
1676 */
1677 static int
1678 ni6_dnsmatch(const char *a, int alen, const char *b, int blen)
1679 {
1680 const char *a0, *b0;
1681 int l;
1682
1683 /* simplest case - need validation? */
1684 if (alen == blen && bcmp(a, b, alen) == 0)
1685 return 1;
1686
1687 a0 = a;
1688 b0 = b;
1689
1690 /* termination is mandatory */
1691 if (alen < 2 || blen < 2)
1692 return 0;
1693 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0')
1694 return 0;
1695 alen--;
1696 blen--;
1697
1698 while (a - a0 < alen && b - b0 < blen) {
1699 if (a - a0 + 1 > alen || b - b0 + 1 > blen)
1700 return 0;
1701
1702 if ((signed char)a[0] < 0 || (signed char)b[0] < 0)
1703 return 0;
1704 /* we don't support compression yet */
1705 if (a[0] >= 64 || b[0] >= 64)
1706 return 0;
1707
1708 /* truncated case */
1709 if (a[0] == 0 && a - a0 == alen - 1)
1710 return 1;
1711 if (b[0] == 0 && b - b0 == blen - 1)
1712 return 1;
1713 if (a[0] == 0 || b[0] == 0)
1714 return 0;
1715
1716 if (a[0] != b[0])
1717 return 0;
1718 l = a[0];
1719 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen)
1720 return 0;
1721 if (bcmp(a + 1, b + 1, l) != 0)
1722 return 0;
1723
1724 a += 1 + l;
1725 b += 1 + l;
1726 }
1727
1728 if (a - a0 == alen && b - b0 == blen)
1729 return 1;
1730 else
1731 return 0;
1732 }
1733
1734 /*
1735 * calculate the number of addresses to be returned in the node info reply.
1736 */
1737 static int
1738 ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, struct ifnet **ifpp,
1739 struct in6_addr *subj)
1740 {
1741 struct ifnet *ifp;
1742 struct in6_ifaddr *ifa6;
1743 struct ifaddr *ifa;
1744 int addrs = 0, addrsofif, iffound = 0;
1745 int niflags = ni6->ni_flags;
1746
1747 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) {
1748 switch (ni6->ni_code) {
1749 case ICMP6_NI_SUBJ_IPV6:
1750 if (subj == NULL) /* must be impossible... */
1751 return (0);
1752 break;
1753 default:
1754 /*
1755 * XXX: we only support IPv6 subject address for
1756 * this Qtype.
1757 */
1758 return (0);
1759 }
1760 }
1761
1762 IFNET_RLOCK_NOSLEEP();
1763 TAILQ_FOREACH(ifp, &V_ifnet, if_list) {
1764 addrsofif = 0;
1765 IF_ADDR_RLOCK(ifp);
1766 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1767 if (ifa->ifa_addr->sa_family != AF_INET6)
1768 continue;
1769 ifa6 = (struct in6_ifaddr *)ifa;
1770
1771 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 &&
1772 IN6_ARE_ADDR_EQUAL(subj, &ifa6->ia_addr.sin6_addr))
1773 iffound = 1;
1774
1775 /*
1776 * IPv4-mapped addresses can only be returned by a
1777 * Node Information proxy, since they represent
1778 * addresses of IPv4-only nodes, which perforce do
1779 * not implement this protocol.
1780 * [icmp-name-lookups-07, Section 5.4]
1781 * So we don't support NI_NODEADDR_FLAG_COMPAT in
1782 * this function at this moment.
1783 */
1784
1785 /* What do we have to do about ::1? */
1786 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
1787 case IPV6_ADDR_SCOPE_LINKLOCAL:
1788 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
1789 continue;
1790 break;
1791 case IPV6_ADDR_SCOPE_SITELOCAL:
1792 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
1793 continue;
1794 break;
1795 case IPV6_ADDR_SCOPE_GLOBAL:
1796 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
1797 continue;
1798 break;
1799 default:
1800 continue;
1801 }
1802
1803 /*
1804 * check if anycast is okay.
1805 * XXX: just experimental. not in the spec.
1806 */
1807 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 &&
1808 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0)
1809 continue; /* we need only unicast addresses */
1810 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
1811 (V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) {
1812 continue;
1813 }
1814 addrsofif++; /* count the address */
1815 }
1816 IF_ADDR_RUNLOCK(ifp);
1817 if (iffound) {
1818 *ifpp = ifp;
1819 IFNET_RUNLOCK_NOSLEEP();
1820 return (addrsofif);
1821 }
1822
1823 addrs += addrsofif;
1824 }
1825 IFNET_RUNLOCK_NOSLEEP();
1826
1827 return (addrs);
1828 }
1829
1830 static int
1831 ni6_store_addrs(struct icmp6_nodeinfo *ni6, struct icmp6_nodeinfo *nni6,
1832 struct ifnet *ifp0, int resid)
1833 {
1834 struct ifnet *ifp;
1835 struct in6_ifaddr *ifa6;
1836 struct ifaddr *ifa;
1837 struct ifnet *ifp_dep = NULL;
1838 int copied = 0, allow_deprecated = 0;
1839 u_char *cp = (u_char *)(nni6 + 1);
1840 int niflags = ni6->ni_flags;
1841 u_int32_t ltime;
1842
1843 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL))
1844 return (0); /* needless to copy */
1845
1846 IFNET_RLOCK_NOSLEEP();
1847 ifp = ifp0 ? ifp0 : TAILQ_FIRST(&V_ifnet);
1848 again:
1849
1850 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) {
1851 IF_ADDR_RLOCK(ifp);
1852 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1853 if (ifa->ifa_addr->sa_family != AF_INET6)
1854 continue;
1855 ifa6 = (struct in6_ifaddr *)ifa;
1856
1857 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 &&
1858 allow_deprecated == 0) {
1859 /*
1860 * prefererred address should be put before
1861 * deprecated addresses.
1862 */
1863
1864 /* record the interface for later search */
1865 if (ifp_dep == NULL)
1866 ifp_dep = ifp;
1867
1868 continue;
1869 } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 &&
1870 allow_deprecated != 0)
1871 continue; /* we now collect deprecated addrs */
1872
1873 /* What do we have to do about ::1? */
1874 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
1875 case IPV6_ADDR_SCOPE_LINKLOCAL:
1876 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
1877 continue;
1878 break;
1879 case IPV6_ADDR_SCOPE_SITELOCAL:
1880 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
1881 continue;
1882 break;
1883 case IPV6_ADDR_SCOPE_GLOBAL:
1884 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
1885 continue;
1886 break;
1887 default:
1888 continue;
1889 }
1890
1891 /*
1892 * check if anycast is okay.
1893 * XXX: just experimental. not in the spec.
1894 */
1895 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 &&
1896 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0)
1897 continue;
1898 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
1899 (V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) {
1900 continue;
1901 }
1902
1903 /* now we can copy the address */
1904 if (resid < sizeof(struct in6_addr) +
1905 sizeof(u_int32_t)) {
1906 IF_ADDR_RUNLOCK(ifp);
1907 /*
1908 * We give up much more copy.
1909 * Set the truncate flag and return.
1910 */
1911 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE;
1912 IFNET_RUNLOCK_NOSLEEP();
1913 return (copied);
1914 }
1915
1916 /*
1917 * Set the TTL of the address.
1918 * The TTL value should be one of the following
1919 * according to the specification:
1920 *
1921 * 1. The remaining lifetime of a DHCP lease on the
1922 * address, or
1923 * 2. The remaining Valid Lifetime of a prefix from
1924 * which the address was derived through Stateless
1925 * Autoconfiguration.
1926 *
1927 * Note that we currently do not support stateful
1928 * address configuration by DHCPv6, so the former
1929 * case can't happen.
1930 */
1931 if (ifa6->ia6_lifetime.ia6t_expire == 0)
1932 ltime = ND6_INFINITE_LIFETIME;
1933 else {
1934 if (ifa6->ia6_lifetime.ia6t_expire >
1935 time_uptime)
1936 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_uptime);
1937 else
1938 ltime = 0;
1939 }
1940
1941 bcopy(<ime, cp, sizeof(u_int32_t));
1942 cp += sizeof(u_int32_t);
1943
1944 /* copy the address itself */
1945 bcopy(&ifa6->ia_addr.sin6_addr, cp,
1946 sizeof(struct in6_addr));
1947 in6_clearscope((struct in6_addr *)cp); /* XXX */
1948 cp += sizeof(struct in6_addr);
1949
1950 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t));
1951 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t));
1952 }
1953 IF_ADDR_RUNLOCK(ifp);
1954 if (ifp0) /* we need search only on the specified IF */
1955 break;
1956 }
1957
1958 if (allow_deprecated == 0 && ifp_dep != NULL) {
1959 ifp = ifp_dep;
1960 allow_deprecated = 1;
1961
1962 goto again;
1963 }
1964
1965 IFNET_RUNLOCK_NOSLEEP();
1966
1967 return (copied);
1968 }
1969
1970 /*
1971 * XXX almost dup'ed code with rip6_input.
1972 */
1973 static int
1974 icmp6_rip6_input(struct mbuf **mp, int off)
1975 {
1976 struct mbuf *m = *mp;
1977 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1978 struct inpcb *in6p;
1979 struct inpcb *last = NULL;
1980 struct sockaddr_in6 fromsa;
1981 struct icmp6_hdr *icmp6;
1982 struct mbuf *opts = NULL;
1983
1984 #ifndef PULLDOWN_TEST
1985 /* this is assumed to be safe. */
1986 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
1987 #else
1988 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
1989 if (icmp6 == NULL) {
1990 /* m is already reclaimed */
1991 return (IPPROTO_DONE);
1992 }
1993 #endif
1994
1995 /*
1996 * XXX: the address may have embedded scope zone ID, which should be
1997 * hidden from applications.
1998 */
1999 bzero(&fromsa, sizeof(fromsa));
2000 fromsa.sin6_family = AF_INET6;
2001 fromsa.sin6_len = sizeof(struct sockaddr_in6);
2002 fromsa.sin6_addr = ip6->ip6_src;
2003 if (sa6_recoverscope(&fromsa)) {
2004 m_freem(m);
2005 return (IPPROTO_DONE);
2006 }
2007
2008 INP_INFO_RLOCK(&V_ripcbinfo);
2009 LIST_FOREACH(in6p, &V_ripcb, inp_list) {
2010 if ((in6p->inp_vflag & INP_IPV6) == 0)
2011 continue;
2012 if (in6p->inp_ip_p != IPPROTO_ICMPV6)
2013 continue;
2014 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) &&
2015 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst))
2016 continue;
2017 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) &&
2018 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src))
2019 continue;
2020 INP_RLOCK(in6p);
2021 if (ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type,
2022 in6p->in6p_icmp6filt)) {
2023 INP_RUNLOCK(in6p);
2024 continue;
2025 }
2026 if (last != NULL) {
2027 struct mbuf *n = NULL;
2028
2029 /*
2030 * Recent network drivers tend to allocate a single
2031 * mbuf cluster, rather than to make a couple of
2032 * mbufs without clusters. Also, since the IPv6 code
2033 * path tries to avoid m_pullup(), it is highly
2034 * probable that we still have an mbuf cluster here
2035 * even though the necessary length can be stored in an
2036 * mbuf's internal buffer.
2037 * Meanwhile, the default size of the receive socket
2038 * buffer for raw sockets is not so large. This means
2039 * the possibility of packet loss is relatively higher
2040 * than before. To avoid this scenario, we copy the
2041 * received data to a separate mbuf that does not use
2042 * a cluster, if possible.
2043 * XXX: it is better to copy the data after stripping
2044 * intermediate headers.
2045 */
2046 if ((m->m_flags & M_EXT) && m->m_next == NULL &&
2047 m->m_len <= MHLEN) {
2048 n = m_get(M_NOWAIT, m->m_type);
2049 if (n != NULL) {
2050 if (m_dup_pkthdr(n, m, M_NOWAIT)) {
2051 bcopy(m->m_data, n->m_data,
2052 m->m_len);
2053 n->m_len = m->m_len;
2054 } else {
2055 m_free(n);
2056 n = NULL;
2057 }
2058 }
2059 }
2060 if (n != NULL ||
2061 (n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
2062 if (last->inp_flags & INP_CONTROLOPTS)
2063 ip6_savecontrol(last, n, &opts);
2064 /* strip intermediate headers */
2065 m_adj(n, off);
2066 SOCKBUF_LOCK(&last->inp_socket->so_rcv);
2067 if (sbappendaddr_locked(
2068 &last->inp_socket->so_rcv,
2069 (struct sockaddr *)&fromsa, n, opts)
2070 == 0) {
2071 /* should notify about lost packet */
2072 m_freem(n);
2073 if (opts) {
2074 m_freem(opts);
2075 }
2076 SOCKBUF_UNLOCK(
2077 &last->inp_socket->so_rcv);
2078 } else
2079 sorwakeup_locked(last->inp_socket);
2080 opts = NULL;
2081 }
2082 INP_RUNLOCK(last);
2083 }
2084 last = in6p;
2085 }
2086 INP_INFO_RUNLOCK(&V_ripcbinfo);
2087 if (last != NULL) {
2088 if (last->inp_flags & INP_CONTROLOPTS)
2089 ip6_savecontrol(last, m, &opts);
2090 /* strip intermediate headers */
2091 m_adj(m, off);
2092
2093 /* avoid using mbuf clusters if possible (see above) */
2094 if ((m->m_flags & M_EXT) && m->m_next == NULL &&
2095 m->m_len <= MHLEN) {
2096 struct mbuf *n;
2097
2098 n = m_get(M_NOWAIT, m->m_type);
2099 if (n != NULL) {
2100 if (m_dup_pkthdr(n, m, M_NOWAIT)) {
2101 bcopy(m->m_data, n->m_data, m->m_len);
2102 n->m_len = m->m_len;
2103
2104 m_freem(m);
2105 m = n;
2106 } else {
2107 m_freem(n);
2108 n = NULL;
2109 }
2110 }
2111 }
2112 SOCKBUF_LOCK(&last->inp_socket->so_rcv);
2113 if (sbappendaddr_locked(&last->inp_socket->so_rcv,
2114 (struct sockaddr *)&fromsa, m, opts) == 0) {
2115 m_freem(m);
2116 if (opts)
2117 m_freem(opts);
2118 SOCKBUF_UNLOCK(&last->inp_socket->so_rcv);
2119 } else
2120 sorwakeup_locked(last->inp_socket);
2121 INP_RUNLOCK(last);
2122 } else {
2123 m_freem(m);
2124 IP6STAT_DEC(ip6s_delivered);
2125 }
2126 return IPPROTO_DONE;
2127 }
2128
2129 /*
2130 * Reflect the ip6 packet back to the source.
2131 * OFF points to the icmp6 header, counted from the top of the mbuf.
2132 */
2133 void
2134 icmp6_reflect(struct mbuf *m, size_t off)
2135 {
2136 struct ip6_hdr *ip6;
2137 struct icmp6_hdr *icmp6;
2138 struct in6_ifaddr *ia = NULL;
2139 int plen;
2140 int type, code;
2141 struct ifnet *outif = NULL;
2142 struct in6_addr origdst, src, *srcp = NULL;
2143
2144 /* too short to reflect */
2145 if (off < sizeof(struct ip6_hdr)) {
2146 nd6log((LOG_DEBUG,
2147 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n",
2148 (u_long)off, (u_long)sizeof(struct ip6_hdr),
2149 __FILE__, __LINE__));
2150 goto bad;
2151 }
2152
2153 /*
2154 * If there are extra headers between IPv6 and ICMPv6, strip
2155 * off that header first.
2156 */
2157 #ifdef DIAGNOSTIC
2158 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN)
2159 panic("assumption failed in icmp6_reflect");
2160 #endif
2161 if (off > sizeof(struct ip6_hdr)) {
2162 size_t l;
2163 struct ip6_hdr nip6;
2164
2165 l = off - sizeof(struct ip6_hdr);
2166 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6);
2167 m_adj(m, l);
2168 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
2169 if (m->m_len < l) {
2170 if ((m = m_pullup(m, l)) == NULL)
2171 return;
2172 }
2173 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6));
2174 } else /* off == sizeof(struct ip6_hdr) */ {
2175 size_t l;
2176 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
2177 if (m->m_len < l) {
2178 if ((m = m_pullup(m, l)) == NULL)
2179 return;
2180 }
2181 }
2182 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr);
2183 ip6 = mtod(m, struct ip6_hdr *);
2184 ip6->ip6_nxt = IPPROTO_ICMPV6;
2185 icmp6 = (struct icmp6_hdr *)(ip6 + 1);
2186 type = icmp6->icmp6_type; /* keep type for statistics */
2187 code = icmp6->icmp6_code; /* ditto. */
2188
2189 origdst = ip6->ip6_dst;
2190 /*
2191 * ip6_input() drops a packet if its src is multicast.
2192 * So, the src is never multicast.
2193 */
2194 ip6->ip6_dst = ip6->ip6_src;
2195
2196 /*
2197 * If the incoming packet was addressed directly to us (i.e. unicast),
2198 * use dst as the src for the reply.
2199 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible
2200 * (for example) when we encounter an error while forwarding procedure
2201 * destined to a duplicated address of ours.
2202 * Note that ip6_getdstifaddr() may fail if we are in an error handling
2203 * procedure of an outgoing packet of our own, in which case we need
2204 * to search in the ifaddr list.
2205 */
2206 if (!IN6_IS_ADDR_MULTICAST(&origdst)) {
2207 if ((ia = ip6_getdstifaddr(m))) {
2208 if (!(ia->ia6_flags &
2209 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)))
2210 srcp = &ia->ia_addr.sin6_addr;
2211 } else {
2212 struct sockaddr_in6 d;
2213
2214 bzero(&d, sizeof(d));
2215 d.sin6_family = AF_INET6;
2216 d.sin6_len = sizeof(d);
2217 d.sin6_addr = origdst;
2218 ia = (struct in6_ifaddr *)
2219 ifa_ifwithaddr((struct sockaddr *)&d);
2220 if (ia &&
2221 !(ia->ia6_flags &
2222 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) {
2223 srcp = &ia->ia_addr.sin6_addr;
2224 }
2225 }
2226 }
2227
2228 if (srcp == NULL) {
2229 int e;
2230 struct sockaddr_in6 sin6;
2231 struct route_in6 ro;
2232
2233 /*
2234 * This case matches to multicasts, our anycast, or unicasts
2235 * that we do not own. Select a source address based on the
2236 * source address of the erroneous packet.
2237 */
2238 bzero(&sin6, sizeof(sin6));
2239 sin6.sin6_family = AF_INET6;
2240 sin6.sin6_len = sizeof(sin6);
2241 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */
2242
2243 bzero(&ro, sizeof(ro));
2244 e = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &src);
2245 if (ro.ro_rt)
2246 RTFREE(ro.ro_rt); /* XXX: we could use this */
2247 if (e) {
2248 char ip6buf[INET6_ADDRSTRLEN];
2249 nd6log((LOG_DEBUG,
2250 "icmp6_reflect: source can't be determined: "
2251 "dst=%s, error=%d\n",
2252 ip6_sprintf(ip6buf, &sin6.sin6_addr), e));
2253 goto bad;
2254 }
2255 srcp = &src;
2256 }
2257
2258 ip6->ip6_src = *srcp;
2259 ip6->ip6_flow = 0;
2260 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
2261 ip6->ip6_vfc |= IPV6_VERSION;
2262 ip6->ip6_nxt = IPPROTO_ICMPV6;
2263 if (outif)
2264 ip6->ip6_hlim = ND_IFINFO(outif)->chlim;
2265 else if (m->m_pkthdr.rcvif) {
2266 /* XXX: This may not be the outgoing interface */
2267 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim;
2268 } else
2269 ip6->ip6_hlim = V_ip6_defhlim;
2270
2271 icmp6->icmp6_cksum = 0;
2272 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6,
2273 sizeof(struct ip6_hdr), plen);
2274
2275 /*
2276 * XXX option handling
2277 */
2278
2279 m->m_flags &= ~(M_BCAST|M_MCAST);
2280
2281 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
2282 if (outif)
2283 icmp6_ifoutstat_inc(outif, type, code);
2284
2285 if (ia != NULL)
2286 ifa_free(&ia->ia_ifa);
2287 return;
2288
2289 bad:
2290 if (ia != NULL)
2291 ifa_free(&ia->ia_ifa);
2292 m_freem(m);
2293 return;
2294 }
2295
2296 void
2297 icmp6_fasttimo(void)
2298 {
2299
2300 mld_fasttimo();
2301 }
2302
2303 void
2304 icmp6_slowtimo(void)
2305 {
2306
2307 mld_slowtimo();
2308 }
2309
2310 static const char *
2311 icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6,
2312 struct in6_addr *tgt6)
2313 {
2314 static char buf[1024];
2315 char ip6bufs[INET6_ADDRSTRLEN];
2316 char ip6bufd[INET6_ADDRSTRLEN];
2317 char ip6buft[INET6_ADDRSTRLEN];
2318 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)",
2319 ip6_sprintf(ip6bufs, src6), ip6_sprintf(ip6bufd, dst6),
2320 ip6_sprintf(ip6buft, tgt6));
2321 return buf;
2322 }
2323
2324 void
2325 icmp6_redirect_input(struct mbuf *m, int off)
2326 {
2327 struct ifnet *ifp;
2328 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
2329 struct nd_redirect *nd_rd;
2330 int icmp6len = ntohs(ip6->ip6_plen);
2331 char *lladdr = NULL;
2332 int lladdrlen = 0;
2333 struct rtentry *rt = NULL;
2334 int is_router;
2335 int is_onlink;
2336 struct in6_addr src6 = ip6->ip6_src;
2337 struct in6_addr redtgt6;
2338 struct in6_addr reddst6;
2339 union nd_opts ndopts;
2340 char ip6buf[INET6_ADDRSTRLEN];
2341
2342 M_ASSERTPKTHDR(m);
2343 KASSERT(m->m_pkthdr.rcvif != NULL, ("%s: no rcvif", __func__));
2344
2345 ifp = m->m_pkthdr.rcvif;
2346
2347 /* XXX if we are router, we don't update route by icmp6 redirect */
2348 if (V_ip6_forwarding)
2349 goto freeit;
2350 if (!V_icmp6_rediraccept)
2351 goto freeit;
2352
2353 #ifndef PULLDOWN_TEST
2354 IP6_EXTHDR_CHECK(m, off, icmp6len,);
2355 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off);
2356 #else
2357 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len);
2358 if (nd_rd == NULL) {
2359 ICMP6STAT_INC(icp6s_tooshort);
2360 return;
2361 }
2362 #endif
2363 redtgt6 = nd_rd->nd_rd_target;
2364 reddst6 = nd_rd->nd_rd_dst;
2365
2366 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) ||
2367 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) {
2368 goto freeit;
2369 }
2370
2371 /* validation */
2372 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) {
2373 nd6log((LOG_ERR,
2374 "ICMP6 redirect sent from %s rejected; "
2375 "must be from linklocal\n",
2376 ip6_sprintf(ip6buf, &src6)));
2377 goto bad;
2378 }
2379 if (ip6->ip6_hlim != 255) {
2380 nd6log((LOG_ERR,
2381 "ICMP6 redirect sent from %s rejected; "
2382 "hlim=%d (must be 255)\n",
2383 ip6_sprintf(ip6buf, &src6), ip6->ip6_hlim));
2384 goto bad;
2385 }
2386 {
2387 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */
2388 struct sockaddr_in6 sin6;
2389 struct in6_addr *gw6;
2390
2391 bzero(&sin6, sizeof(sin6));
2392 sin6.sin6_family = AF_INET6;
2393 sin6.sin6_len = sizeof(struct sockaddr_in6);
2394 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6));
2395 rt = in6_rtalloc1((struct sockaddr *)&sin6, 0, 0UL, RT_DEFAULT_FIB);
2396 if (rt) {
2397 if (rt->rt_gateway == NULL ||
2398 rt->rt_gateway->sa_family != AF_INET6) {
2399 RTFREE_LOCKED(rt);
2400 nd6log((LOG_ERR,
2401 "ICMP6 redirect rejected; no route "
2402 "with inet6 gateway found for redirect dst: %s\n",
2403 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2404 goto bad;
2405 }
2406
2407 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr);
2408 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) {
2409 RTFREE_LOCKED(rt);
2410 nd6log((LOG_ERR,
2411 "ICMP6 redirect rejected; "
2412 "not equal to gw-for-src=%s (must be same): "
2413 "%s\n",
2414 ip6_sprintf(ip6buf, gw6),
2415 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2416 goto bad;
2417 }
2418 } else {
2419 nd6log((LOG_ERR,
2420 "ICMP6 redirect rejected; "
2421 "no route found for redirect dst: %s\n",
2422 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2423 goto bad;
2424 }
2425 RTFREE_LOCKED(rt);
2426 rt = NULL;
2427 }
2428 if (IN6_IS_ADDR_MULTICAST(&reddst6)) {
2429 nd6log((LOG_ERR,
2430 "ICMP6 redirect rejected; "
2431 "redirect dst must be unicast: %s\n",
2432 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2433 goto bad;
2434 }
2435
2436 is_router = is_onlink = 0;
2437 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
2438 is_router = 1; /* router case */
2439 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0)
2440 is_onlink = 1; /* on-link destination case */
2441 if (!is_router && !is_onlink) {
2442 nd6log((LOG_ERR,
2443 "ICMP6 redirect rejected; "
2444 "neither router case nor onlink case: %s\n",
2445 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2446 goto bad;
2447 }
2448 /* validation passed */
2449
2450 icmp6len -= sizeof(*nd_rd);
2451 nd6_option_init(nd_rd + 1, icmp6len, &ndopts);
2452 if (nd6_options(&ndopts) < 0) {
2453 nd6log((LOG_INFO, "%s: invalid ND option, rejected: %s\n",
2454 __func__, icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2455 /* nd6_options have incremented stats */
2456 goto freeit;
2457 }
2458
2459 if (ndopts.nd_opts_tgt_lladdr) {
2460 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
2461 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
2462 }
2463
2464 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
2465 nd6log((LOG_INFO, "%s: lladdrlen mismatch for %s "
2466 "(if %d, icmp6 packet %d): %s\n",
2467 __func__, ip6_sprintf(ip6buf, &redtgt6),
2468 ifp->if_addrlen, lladdrlen - 2,
2469 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2470 goto bad;
2471 }
2472
2473 /* RFC 2461 8.3 */
2474 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT,
2475 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER);
2476
2477 if (!is_onlink) { /* better router case. perform rtredirect. */
2478 /* perform rtredirect */
2479 struct sockaddr_in6 sdst;
2480 struct sockaddr_in6 sgw;
2481 struct sockaddr_in6 ssrc;
2482 u_int fibnum;
2483
2484 bzero(&sdst, sizeof(sdst));
2485 bzero(&sgw, sizeof(sgw));
2486 bzero(&ssrc, sizeof(ssrc));
2487 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6;
2488 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len =
2489 sizeof(struct sockaddr_in6);
2490 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr));
2491 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
2492 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr));
2493 for (fibnum = 0; fibnum < rt_numfibs; fibnum++)
2494 in6_rtredirect((struct sockaddr *)&sdst,
2495 (struct sockaddr *)&sgw, (struct sockaddr *)NULL,
2496 RTF_GATEWAY | RTF_HOST, (struct sockaddr *)&ssrc,
2497 fibnum);
2498 }
2499 /* finally update cached route in each socket via pfctlinput */
2500 {
2501 struct sockaddr_in6 sdst;
2502
2503 bzero(&sdst, sizeof(sdst));
2504 sdst.sin6_family = AF_INET6;
2505 sdst.sin6_len = sizeof(struct sockaddr_in6);
2506 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
2507 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst);
2508 #ifdef IPSEC
2509 key_sa_routechange((struct sockaddr *)&sdst);
2510 #endif /* IPSEC */
2511 }
2512
2513 freeit:
2514 m_freem(m);
2515 return;
2516
2517 bad:
2518 ICMP6STAT_INC(icp6s_badredirect);
2519 m_freem(m);
2520 }
2521
2522 void
2523 icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt)
2524 {
2525 struct ifnet *ifp; /* my outgoing interface */
2526 struct in6_addr *ifp_ll6;
2527 struct in6_addr *router_ll6;
2528 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */
2529 struct mbuf *m = NULL; /* newly allocated one */
2530 struct m_tag *mtag;
2531 struct ip6_hdr *ip6; /* m as struct ip6_hdr */
2532 struct nd_redirect *nd_rd;
2533 struct llentry *ln = NULL;
2534 size_t maxlen;
2535 u_char *p;
2536 struct ifnet *outif = NULL;
2537 struct sockaddr_in6 src_sa;
2538
2539 icmp6_errcount(ND_REDIRECT, 0);
2540
2541 /* if we are not router, we don't send icmp6 redirect */
2542 if (!V_ip6_forwarding)
2543 goto fail;
2544
2545 /* sanity check */
2546 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp))
2547 goto fail;
2548
2549 /*
2550 * Address check:
2551 * the source address must identify a neighbor, and
2552 * the destination address must not be a multicast address
2553 * [RFC 2461, sec 8.2]
2554 */
2555 sip6 = mtod(m0, struct ip6_hdr *);
2556 bzero(&src_sa, sizeof(src_sa));
2557 src_sa.sin6_family = AF_INET6;
2558 src_sa.sin6_len = sizeof(src_sa);
2559 src_sa.sin6_addr = sip6->ip6_src;
2560 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0)
2561 goto fail;
2562 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst))
2563 goto fail; /* what should we do here? */
2564
2565 /* rate limit */
2566 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0))
2567 goto fail;
2568
2569 /*
2570 * Since we are going to append up to 1280 bytes (= IPV6_MMTU),
2571 * we almost always ask for an mbuf cluster for simplicity.
2572 * (MHLEN < IPV6_MMTU is almost always true)
2573 */
2574 #if IPV6_MMTU >= MCLBYTES
2575 # error assumption failed about IPV6_MMTU and MCLBYTES
2576 #endif
2577 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
2578 if (m == NULL)
2579 goto fail;
2580 M_SETFIB(m, rt->rt_fibnum);
2581 maxlen = M_TRAILINGSPACE(m);
2582 maxlen = min(IPV6_MMTU, maxlen);
2583 /* just for safety */
2584 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) +
2585 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) {
2586 goto fail;
2587 }
2588
2589 {
2590 /* get ip6 linklocal address for ifp(my outgoing interface). */
2591 struct in6_ifaddr *ia;
2592 if ((ia = in6ifa_ifpforlinklocal(ifp,
2593 IN6_IFF_NOTREADY|
2594 IN6_IFF_ANYCAST)) == NULL)
2595 goto fail;
2596 ifp_ll6 = &ia->ia_addr.sin6_addr;
2597 /* XXXRW: reference released prematurely. */
2598 ifa_free(&ia->ia_ifa);
2599 }
2600
2601 /* get ip6 linklocal address for the router. */
2602 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) {
2603 struct sockaddr_in6 *sin6;
2604 sin6 = (struct sockaddr_in6 *)rt->rt_gateway;
2605 router_ll6 = &sin6->sin6_addr;
2606 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6))
2607 router_ll6 = (struct in6_addr *)NULL;
2608 } else
2609 router_ll6 = (struct in6_addr *)NULL;
2610
2611 /* ip6 */
2612 ip6 = mtod(m, struct ip6_hdr *);
2613 ip6->ip6_flow = 0;
2614 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
2615 ip6->ip6_vfc |= IPV6_VERSION;
2616 /* ip6->ip6_plen will be set later */
2617 ip6->ip6_nxt = IPPROTO_ICMPV6;
2618 ip6->ip6_hlim = 255;
2619 /* ip6->ip6_src must be linklocal addr for my outgoing if. */
2620 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr));
2621 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr));
2622
2623 /* ND Redirect */
2624 nd_rd = (struct nd_redirect *)(ip6 + 1);
2625 nd_rd->nd_rd_type = ND_REDIRECT;
2626 nd_rd->nd_rd_code = 0;
2627 nd_rd->nd_rd_reserved = 0;
2628 if (rt->rt_flags & RTF_GATEWAY) {
2629 /*
2630 * nd_rd->nd_rd_target must be a link-local address in
2631 * better router cases.
2632 */
2633 if (!router_ll6)
2634 goto fail;
2635 bcopy(router_ll6, &nd_rd->nd_rd_target,
2636 sizeof(nd_rd->nd_rd_target));
2637 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2638 sizeof(nd_rd->nd_rd_dst));
2639 } else {
2640 /* make sure redtgt == reddst */
2641 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target,
2642 sizeof(nd_rd->nd_rd_target));
2643 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2644 sizeof(nd_rd->nd_rd_dst));
2645 }
2646
2647 p = (u_char *)(nd_rd + 1);
2648
2649 if (!router_ll6)
2650 goto nolladdropt;
2651
2652 {
2653 /* target lladdr option */
2654 int len;
2655 struct nd_opt_hdr *nd_opt;
2656 char *lladdr;
2657
2658 IF_AFDATA_RLOCK(ifp);
2659 ln = nd6_lookup(router_ll6, 0, ifp);
2660 IF_AFDATA_RUNLOCK(ifp);
2661 if (ln == NULL)
2662 goto nolladdropt;
2663
2664 len = sizeof(*nd_opt) + ifp->if_addrlen;
2665 len = (len + 7) & ~7; /* round by 8 */
2666 /* safety check */
2667 if (len + (p - (u_char *)ip6) > maxlen)
2668 goto nolladdropt;
2669
2670 if (ln->la_flags & LLE_VALID) {
2671 nd_opt = (struct nd_opt_hdr *)p;
2672 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
2673 nd_opt->nd_opt_len = len >> 3;
2674 lladdr = (char *)(nd_opt + 1);
2675 bcopy(&ln->ll_addr, lladdr, ifp->if_addrlen);
2676 p += len;
2677 }
2678 }
2679 nolladdropt:
2680 if (ln != NULL)
2681 LLE_RUNLOCK(ln);
2682
2683 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2684
2685 /* just to be safe */
2686 #ifdef M_DECRYPTED /*not openbsd*/
2687 if (m0->m_flags & M_DECRYPTED)
2688 goto noredhdropt;
2689 #endif
2690 if (p - (u_char *)ip6 > maxlen)
2691 goto noredhdropt;
2692
2693 {
2694 /* redirected header option */
2695 int len;
2696 struct nd_opt_rd_hdr *nd_opt_rh;
2697
2698 /*
2699 * compute the maximum size for icmp6 redirect header option.
2700 * XXX room for auth header?
2701 */
2702 len = maxlen - (p - (u_char *)ip6);
2703 len &= ~7;
2704
2705 /* This is just for simplicity. */
2706 if (m0->m_pkthdr.len != m0->m_len) {
2707 if (m0->m_next) {
2708 m_freem(m0->m_next);
2709 m0->m_next = NULL;
2710 }
2711 m0->m_pkthdr.len = m0->m_len;
2712 }
2713
2714 /*
2715 * Redirected header option spec (RFC2461 4.6.3) talks nothing
2716 * about padding/truncate rule for the original IP packet.
2717 * From the discussion on IPv6imp in Feb 1999,
2718 * the consensus was:
2719 * - "attach as much as possible" is the goal
2720 * - pad if not aligned (original size can be guessed by
2721 * original ip6 header)
2722 * Following code adds the padding if it is simple enough,
2723 * and truncates if not.
2724 */
2725 if (m0->m_next || m0->m_pkthdr.len != m0->m_len)
2726 panic("assumption failed in %s:%d", __FILE__,
2727 __LINE__);
2728
2729 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) {
2730 /* not enough room, truncate */
2731 m0->m_pkthdr.len = m0->m_len = len -
2732 sizeof(*nd_opt_rh);
2733 } else {
2734 /* enough room, pad or truncate */
2735 size_t extra;
2736
2737 extra = m0->m_pkthdr.len % 8;
2738 if (extra) {
2739 /* pad if easy enough, truncate if not */
2740 if (8 - extra <= M_TRAILINGSPACE(m0)) {
2741 /* pad */
2742 m0->m_len += (8 - extra);
2743 m0->m_pkthdr.len += (8 - extra);
2744 } else {
2745 /* truncate */
2746 m0->m_pkthdr.len -= extra;
2747 m0->m_len -= extra;
2748 }
2749 }
2750 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh);
2751 m0->m_pkthdr.len = m0->m_len = len -
2752 sizeof(*nd_opt_rh);
2753 }
2754
2755 nd_opt_rh = (struct nd_opt_rd_hdr *)p;
2756 bzero(nd_opt_rh, sizeof(*nd_opt_rh));
2757 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER;
2758 nd_opt_rh->nd_opt_rh_len = len >> 3;
2759 p += sizeof(*nd_opt_rh);
2760 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2761
2762 /* connect m0 to m */
2763 m_tag_delete_chain(m0, NULL);
2764 m0->m_flags &= ~M_PKTHDR;
2765 m->m_next = m0;
2766 m->m_pkthdr.len = m->m_len + m0->m_len;
2767 m0 = NULL;
2768 }
2769 noredhdropt:;
2770 if (m0) {
2771 m_freem(m0);
2772 m0 = NULL;
2773 }
2774
2775 /* XXX: clear embedded link IDs in the inner header */
2776 in6_clearscope(&sip6->ip6_src);
2777 in6_clearscope(&sip6->ip6_dst);
2778 in6_clearscope(&nd_rd->nd_rd_target);
2779 in6_clearscope(&nd_rd->nd_rd_dst);
2780
2781 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
2782
2783 nd_rd->nd_rd_cksum = 0;
2784 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6,
2785 sizeof(*ip6), ntohs(ip6->ip6_plen));
2786
2787 if (send_sendso_input_hook != NULL) {
2788 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, sizeof(unsigned short),
2789 M_NOWAIT);
2790 if (mtag == NULL)
2791 goto fail;
2792 *(unsigned short *)(mtag + 1) = nd_rd->nd_rd_type;
2793 m_tag_prepend(m, mtag);
2794 }
2795
2796 /* send the packet to outside... */
2797 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
2798 if (outif) {
2799 icmp6_ifstat_inc(outif, ifs6_out_msg);
2800 icmp6_ifstat_inc(outif, ifs6_out_redirect);
2801 }
2802 ICMP6STAT_INC(icp6s_outhist[ND_REDIRECT]);
2803
2804 return;
2805
2806 fail:
2807 if (m)
2808 m_freem(m);
2809 if (m0)
2810 m_freem(m0);
2811 }
2812
2813 /*
2814 * ICMPv6 socket option processing.
2815 */
2816 int
2817 icmp6_ctloutput(struct socket *so, struct sockopt *sopt)
2818 {
2819 int error = 0;
2820 int optlen;
2821 struct inpcb *inp = sotoinpcb(so);
2822 int level, op, optname;
2823
2824 if (sopt) {
2825 level = sopt->sopt_level;
2826 op = sopt->sopt_dir;
2827 optname = sopt->sopt_name;
2828 optlen = sopt->sopt_valsize;
2829 } else
2830 level = op = optname = optlen = 0;
2831
2832 if (level != IPPROTO_ICMPV6) {
2833 return EINVAL;
2834 }
2835
2836 switch (op) {
2837 case PRCO_SETOPT:
2838 switch (optname) {
2839 case ICMP6_FILTER:
2840 {
2841 struct icmp6_filter ic6f;
2842
2843 if (optlen != sizeof(ic6f)) {
2844 error = EMSGSIZE;
2845 break;
2846 }
2847 error = sooptcopyin(sopt, &ic6f, optlen, optlen);
2848 if (error == 0) {
2849 INP_WLOCK(inp);
2850 *inp->in6p_icmp6filt = ic6f;
2851 INP_WUNLOCK(inp);
2852 }
2853 break;
2854 }
2855
2856 default:
2857 error = ENOPROTOOPT;
2858 break;
2859 }
2860 break;
2861
2862 case PRCO_GETOPT:
2863 switch (optname) {
2864 case ICMP6_FILTER:
2865 {
2866 struct icmp6_filter ic6f;
2867
2868 INP_RLOCK(inp);
2869 ic6f = *inp->in6p_icmp6filt;
2870 INP_RUNLOCK(inp);
2871 error = sooptcopyout(sopt, &ic6f, sizeof(ic6f));
2872 break;
2873 }
2874
2875 default:
2876 error = ENOPROTOOPT;
2877 break;
2878 }
2879 break;
2880 }
2881
2882 return (error);
2883 }
2884
2885 /*
2886 * Perform rate limit check.
2887 * Returns 0 if it is okay to send the icmp6 packet.
2888 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate
2889 * limitation.
2890 *
2891 * XXX per-destination/type check necessary?
2892 *
2893 * dst - not used at this moment
2894 * type - not used at this moment
2895 * code - not used at this moment
2896 */
2897 static int
2898 icmp6_ratelimit(const struct in6_addr *dst, const int type,
2899 const int code)
2900 {
2901 int ret;
2902
2903 ret = 0; /* okay to send */
2904
2905 /* PPS limit */
2906 if (!ppsratecheck(&V_icmp6errppslim_last, &V_icmp6errpps_count,
2907 V_icmp6errppslim)) {
2908 /* The packet is subject to rate limit */
2909 ret++;
2910 }
2911
2912 return ret;
2913 }
Cache object: 06096c0806ad5658709826dbb9bae7aa
|