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/10.4/sys/netinet6/icmp6.c 303459 2016-07-28 20:11:34Z sbruno $");
65
66 #include "opt_inet.h"
67 #include "opt_inet6.h"
68
69 #include <sys/param.h>
70 #include <sys/domain.h>
71 #include <sys/jail.h>
72 #include <sys/kernel.h>
73 #include <sys/lock.h>
74 #include <sys/malloc.h>
75 #include <sys/mbuf.h>
76 #include <sys/proc.h>
77 #include <sys/protosw.h>
78 #include <sys/signalvar.h>
79 #include <sys/socket.h>
80 #include <sys/socketvar.h>
81 #include <sys/sx.h>
82 #include <sys/syslog.h>
83 #include <sys/systm.h>
84 #include <sys/time.h>
85
86 #include <net/if.h>
87 #include <net/if_dl.h>
88 #include <net/if_llatbl.h>
89 #include <net/if_types.h>
90 #include <net/route.h>
91 #include <net/vnet.h>
92
93 #include <netinet/in.h>
94 #include <netinet/in_pcb.h>
95 #include <netinet/in_var.h>
96 #include <netinet/ip6.h>
97 #include <netinet/icmp6.h>
98 #include <netinet/tcp_var.h>
99
100 #include <netinet6/in6_ifattach.h>
101 #include <netinet6/in6_pcb.h>
102 #include <netinet6/ip6protosw.h>
103 #include <netinet6/ip6_var.h>
104 #include <netinet6/scope6_var.h>
105 #include <netinet6/mld6_var.h>
106 #include <netinet6/nd6.h>
107 #include <netinet6/send.h>
108
109 extern struct domain inet6domain;
110
111 VNET_PCPUSTAT_DEFINE(struct icmp6stat, icmp6stat);
112 VNET_PCPUSTAT_SYSINIT(icmp6stat);
113
114 #ifdef VIMAGE
115 VNET_PCPUSTAT_SYSUNINIT(icmp6stat);
116 #endif /* VIMAGE */
117
118 VNET_DECLARE(struct inpcbinfo, ripcbinfo);
119 VNET_DECLARE(struct inpcbhead, ripcb);
120 VNET_DECLARE(int, icmp6errppslim);
121 static VNET_DEFINE(int, icmp6errpps_count) = 0;
122 static VNET_DEFINE(struct timeval, icmp6errppslim_last);
123 VNET_DECLARE(int, icmp6_nodeinfo);
124
125 #define V_ripcbinfo VNET(ripcbinfo)
126 #define V_ripcb VNET(ripcb)
127 #define V_icmp6errppslim VNET(icmp6errppslim)
128 #define V_icmp6errpps_count VNET(icmp6errpps_count)
129 #define V_icmp6errppslim_last VNET(icmp6errppslim_last)
130 #define V_icmp6_nodeinfo VNET(icmp6_nodeinfo)
131
132 static void icmp6_errcount(int, int);
133 static int icmp6_rip6_input(struct mbuf **, int);
134 static int icmp6_ratelimit(const struct in6_addr *, const int, const int);
135 static const char *icmp6_redirect_diag(struct in6_addr *,
136 struct in6_addr *, struct in6_addr *);
137 static struct mbuf *ni6_input(struct mbuf *, int);
138 static struct mbuf *ni6_nametodns(const char *, int, int);
139 static int ni6_dnsmatch(const char *, int, const char *, int);
140 static int ni6_addrs(struct icmp6_nodeinfo *, struct mbuf *,
141 struct ifnet **, struct in6_addr *);
142 static int ni6_store_addrs(struct icmp6_nodeinfo *, struct icmp6_nodeinfo *,
143 struct ifnet *, int);
144 static int icmp6_notify_error(struct mbuf **, int, int, int);
145
146 /*
147 * Kernel module interface for updating icmp6stat. The argument is an index
148 * into icmp6stat treated as an array of u_quad_t. While this encodes the
149 * general layout of icmp6stat into the caller, it doesn't encode its
150 * location, so that future changes to add, for example, per-CPU stats
151 * support won't cause binary compatibility problems for kernel modules.
152 */
153 void
154 kmod_icmp6stat_inc(int statnum)
155 {
156
157 counter_u64_add(VNET(icmp6stat)[statnum], 1);
158 }
159
160 static void
161 icmp6_errcount(int type, int code)
162 {
163 switch (type) {
164 case ICMP6_DST_UNREACH:
165 switch (code) {
166 case ICMP6_DST_UNREACH_NOROUTE:
167 ICMP6STAT_INC(icp6s_odst_unreach_noroute);
168 return;
169 case ICMP6_DST_UNREACH_ADMIN:
170 ICMP6STAT_INC(icp6s_odst_unreach_admin);
171 return;
172 case ICMP6_DST_UNREACH_BEYONDSCOPE:
173 ICMP6STAT_INC(icp6s_odst_unreach_beyondscope);
174 return;
175 case ICMP6_DST_UNREACH_ADDR:
176 ICMP6STAT_INC(icp6s_odst_unreach_addr);
177 return;
178 case ICMP6_DST_UNREACH_NOPORT:
179 ICMP6STAT_INC(icp6s_odst_unreach_noport);
180 return;
181 }
182 break;
183 case ICMP6_PACKET_TOO_BIG:
184 ICMP6STAT_INC(icp6s_opacket_too_big);
185 return;
186 case ICMP6_TIME_EXCEEDED:
187 switch (code) {
188 case ICMP6_TIME_EXCEED_TRANSIT:
189 ICMP6STAT_INC(icp6s_otime_exceed_transit);
190 return;
191 case ICMP6_TIME_EXCEED_REASSEMBLY:
192 ICMP6STAT_INC(icp6s_otime_exceed_reassembly);
193 return;
194 }
195 break;
196 case ICMP6_PARAM_PROB:
197 switch (code) {
198 case ICMP6_PARAMPROB_HEADER:
199 ICMP6STAT_INC(icp6s_oparamprob_header);
200 return;
201 case ICMP6_PARAMPROB_NEXTHEADER:
202 ICMP6STAT_INC(icp6s_oparamprob_nextheader);
203 return;
204 case ICMP6_PARAMPROB_OPTION:
205 ICMP6STAT_INC(icp6s_oparamprob_option);
206 return;
207 }
208 break;
209 case ND_REDIRECT:
210 ICMP6STAT_INC(icp6s_oredirect);
211 return;
212 }
213 ICMP6STAT_INC(icp6s_ounknown);
214 }
215
216 /*
217 * A wrapper function for icmp6_error() necessary when the erroneous packet
218 * may not contain enough scope zone information.
219 */
220 void
221 icmp6_error2(struct mbuf *m, int type, int code, int param,
222 struct ifnet *ifp)
223 {
224 struct ip6_hdr *ip6;
225
226 if (ifp == NULL)
227 return;
228
229 #ifndef PULLDOWN_TEST
230 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), );
231 #else
232 if (m->m_len < sizeof(struct ip6_hdr)) {
233 m = m_pullup(m, sizeof(struct ip6_hdr));
234 if (m == NULL)
235 return;
236 }
237 #endif
238
239 ip6 = mtod(m, struct ip6_hdr *);
240
241 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0)
242 return;
243 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0)
244 return;
245
246 icmp6_error(m, type, code, param);
247 }
248
249 /*
250 * Generate an error packet of type error in response to bad IP6 packet.
251 */
252 void
253 icmp6_error(struct mbuf *m, int type, int code, int param)
254 {
255 struct ip6_hdr *oip6, *nip6;
256 struct icmp6_hdr *icmp6;
257 u_int preplen;
258 int off;
259 int nxt;
260
261 ICMP6STAT_INC(icp6s_error);
262
263 /* count per-type-code statistics */
264 icmp6_errcount(type, code);
265
266 #ifdef M_DECRYPTED /*not openbsd*/
267 if (m->m_flags & M_DECRYPTED) {
268 ICMP6STAT_INC(icp6s_canterror);
269 goto freeit;
270 }
271 #endif
272
273 #ifndef PULLDOWN_TEST
274 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), );
275 #else
276 if (m->m_len < sizeof(struct ip6_hdr)) {
277 m = m_pullup(m, sizeof(struct ip6_hdr));
278 if (m == NULL)
279 return;
280 }
281 #endif
282 oip6 = mtod(m, struct ip6_hdr *);
283
284 /*
285 * If the destination address of the erroneous packet is a multicast
286 * address, or the packet was sent using link-layer multicast,
287 * we should basically suppress sending an error (RFC 2463, Section
288 * 2.4).
289 * We have two exceptions (the item e.2 in that section):
290 * - the Packet Too Big message can be sent for path MTU discovery.
291 * - the Parameter Problem Message that can be allowed an icmp6 error
292 * in the option type field. This check has been done in
293 * ip6_unknown_opt(), so we can just check the type and code.
294 */
295 if ((m->m_flags & (M_BCAST|M_MCAST) ||
296 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) &&
297 (type != ICMP6_PACKET_TOO_BIG &&
298 (type != ICMP6_PARAM_PROB ||
299 code != ICMP6_PARAMPROB_OPTION)))
300 goto freeit;
301
302 /*
303 * RFC 2463, 2.4 (e.5): source address check.
304 * XXX: the case of anycast source?
305 */
306 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) ||
307 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src))
308 goto freeit;
309
310 /*
311 * If we are about to send ICMPv6 against ICMPv6 error/redirect,
312 * don't do it.
313 */
314 nxt = -1;
315 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
316 if (off >= 0 && nxt == IPPROTO_ICMPV6) {
317 struct icmp6_hdr *icp;
318
319 #ifndef PULLDOWN_TEST
320 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), );
321 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
322 #else
323 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off,
324 sizeof(*icp));
325 if (icp == NULL) {
326 ICMP6STAT_INC(icp6s_tooshort);
327 return;
328 }
329 #endif
330 if (icp->icmp6_type < ICMP6_ECHO_REQUEST ||
331 icp->icmp6_type == ND_REDIRECT) {
332 /*
333 * ICMPv6 error
334 * Special case: for redirect (which is
335 * informational) we must not send icmp6 error.
336 */
337 ICMP6STAT_INC(icp6s_canterror);
338 goto freeit;
339 } else {
340 /* ICMPv6 informational - send the error */
341 }
342 } else {
343 /* non-ICMPv6 - send the error */
344 }
345
346 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */
347
348 /* Finally, do rate limitation check. */
349 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) {
350 ICMP6STAT_INC(icp6s_toofreq);
351 goto freeit;
352 }
353
354 /*
355 * OK, ICMP6 can be generated.
356 */
357
358 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN)
359 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len);
360
361 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
362 M_PREPEND(m, preplen, M_NOWAIT); /* FIB is also copied over. */
363 if (m == NULL) {
364 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__));
365 return;
366 }
367
368 nip6 = mtod(m, struct ip6_hdr *);
369 nip6->ip6_src = oip6->ip6_src;
370 nip6->ip6_dst = oip6->ip6_dst;
371
372 in6_clearscope(&oip6->ip6_src);
373 in6_clearscope(&oip6->ip6_dst);
374
375 icmp6 = (struct icmp6_hdr *)(nip6 + 1);
376 icmp6->icmp6_type = type;
377 icmp6->icmp6_code = code;
378 icmp6->icmp6_pptr = htonl((u_int32_t)param);
379
380 /*
381 * icmp6_reflect() is designed to be in the input path.
382 * icmp6_error() can be called from both input and output path,
383 * and if we are in output path rcvif could contain bogus value.
384 * clear m->m_pkthdr.rcvif for safety, we should have enough scope
385 * information in ip header (nip6).
386 */
387 m->m_pkthdr.rcvif = NULL;
388
389 ICMP6STAT_INC(icp6s_outhist[type]);
390 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */
391
392 return;
393
394 freeit:
395 /*
396 * If we can't tell whether or not we can generate ICMP6, free it.
397 */
398 m_freem(m);
399 }
400
401 /*
402 * Process a received ICMP6 message.
403 */
404 int
405 icmp6_input(struct mbuf **mp, int *offp, int proto)
406 {
407 struct mbuf *m = *mp, *n;
408 struct ifnet *ifp;
409 struct ip6_hdr *ip6, *nip6;
410 struct icmp6_hdr *icmp6, *nicmp6;
411 int off = *offp;
412 int icmp6len = m->m_pkthdr.len - *offp;
413 int code, sum, noff;
414 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
415 int ip6len, error;
416
417 ifp = m->m_pkthdr.rcvif;
418
419 #ifndef PULLDOWN_TEST
420 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE);
421 /* m might change if M_LOOP. So, call mtod after this */
422 #endif
423
424 /*
425 * Locate icmp6 structure in mbuf, and check
426 * that not corrupted and of at least minimum length
427 */
428
429 ip6 = mtod(m, struct ip6_hdr *);
430 ip6len = sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen);
431 if (icmp6len < sizeof(struct icmp6_hdr)) {
432 ICMP6STAT_INC(icp6s_tooshort);
433 goto freeit;
434 }
435
436 /*
437 * Check multicast group membership.
438 * Note: SSM filters are not applied for ICMPv6 traffic.
439 */
440 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
441 struct in6_multi *inm;
442
443 inm = in6m_lookup(ifp, &ip6->ip6_dst);
444 if (inm == NULL) {
445 IP6STAT_INC(ip6s_notmember);
446 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
447 goto freeit;
448 }
449 }
450
451 /*
452 * calculate the checksum
453 */
454 #ifndef PULLDOWN_TEST
455 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
456 #else
457 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
458 if (icmp6 == NULL) {
459 ICMP6STAT_INC(icp6s_tooshort);
460 return IPPROTO_DONE;
461 }
462 #endif
463 code = icmp6->icmp6_code;
464
465 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) {
466 nd6log((LOG_ERR,
467 "ICMP6 checksum error(%d|%x) %s\n",
468 icmp6->icmp6_type, sum,
469 ip6_sprintf(ip6bufs, &ip6->ip6_src)));
470 ICMP6STAT_INC(icp6s_checksum);
471 goto freeit;
472 }
473
474 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) {
475 /*
476 * Deliver very specific ICMP6 type only.
477 * This is important to deliver TOOBIG. Otherwise PMTUD
478 * will not work.
479 */
480 switch (icmp6->icmp6_type) {
481 case ICMP6_DST_UNREACH:
482 case ICMP6_PACKET_TOO_BIG:
483 case ICMP6_TIME_EXCEEDED:
484 break;
485 default:
486 goto freeit;
487 }
488 }
489
490 ICMP6STAT_INC(icp6s_inhist[icmp6->icmp6_type]);
491 icmp6_ifstat_inc(ifp, ifs6_in_msg);
492 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK)
493 icmp6_ifstat_inc(ifp, ifs6_in_error);
494
495 switch (icmp6->icmp6_type) {
496 case ICMP6_DST_UNREACH:
497 icmp6_ifstat_inc(ifp, ifs6_in_dstunreach);
498 switch (code) {
499 case ICMP6_DST_UNREACH_NOROUTE:
500 code = PRC_UNREACH_NET;
501 break;
502 case ICMP6_DST_UNREACH_ADMIN:
503 icmp6_ifstat_inc(ifp, ifs6_in_adminprohib);
504 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */
505 break;
506 case ICMP6_DST_UNREACH_ADDR:
507 code = PRC_HOSTDEAD;
508 break;
509 case ICMP6_DST_UNREACH_BEYONDSCOPE:
510 /* I mean "source address was incorrect." */
511 code = PRC_PARAMPROB;
512 break;
513 case ICMP6_DST_UNREACH_NOPORT:
514 code = PRC_UNREACH_PORT;
515 break;
516 default:
517 goto badcode;
518 }
519 goto deliver;
520 break;
521
522 case ICMP6_PACKET_TOO_BIG:
523 icmp6_ifstat_inc(ifp, ifs6_in_pkttoobig);
524
525 /* validation is made in icmp6_mtudisc_update */
526
527 code = PRC_MSGSIZE;
528
529 /*
530 * Updating the path MTU will be done after examining
531 * intermediate extension headers.
532 */
533 goto deliver;
534 break;
535
536 case ICMP6_TIME_EXCEEDED:
537 icmp6_ifstat_inc(ifp, ifs6_in_timeexceed);
538 switch (code) {
539 case ICMP6_TIME_EXCEED_TRANSIT:
540 code = PRC_TIMXCEED_INTRANS;
541 break;
542 case ICMP6_TIME_EXCEED_REASSEMBLY:
543 code = PRC_TIMXCEED_REASS;
544 break;
545 default:
546 goto badcode;
547 }
548 goto deliver;
549 break;
550
551 case ICMP6_PARAM_PROB:
552 icmp6_ifstat_inc(ifp, ifs6_in_paramprob);
553 switch (code) {
554 case ICMP6_PARAMPROB_NEXTHEADER:
555 code = PRC_UNREACH_PROTOCOL;
556 break;
557 case ICMP6_PARAMPROB_HEADER:
558 case ICMP6_PARAMPROB_OPTION:
559 code = PRC_PARAMPROB;
560 break;
561 default:
562 goto badcode;
563 }
564 goto deliver;
565 break;
566
567 case ICMP6_ECHO_REQUEST:
568 icmp6_ifstat_inc(ifp, ifs6_in_echo);
569 if (code != 0)
570 goto badcode;
571 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) {
572 /* Give up remote */
573 break;
574 }
575 if ((n->m_flags & M_EXT) != 0
576 || n->m_len < off + sizeof(struct icmp6_hdr)) {
577 struct mbuf *n0 = n;
578 int n0len;
579
580 CTASSERT(sizeof(*nip6) + sizeof(*nicmp6) <= MHLEN);
581 n = m_gethdr(M_NOWAIT, n0->m_type);
582 if (n == NULL) {
583 /* Give up remote */
584 m_freem(n0);
585 break;
586 }
587
588 m_move_pkthdr(n, n0); /* FIB copied. */
589 n0len = n0->m_pkthdr.len; /* save for use below */
590 /*
591 * Copy IPv6 and ICMPv6 only.
592 */
593 nip6 = mtod(n, struct ip6_hdr *);
594 bcopy(ip6, nip6, sizeof(struct ip6_hdr));
595 nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
596 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
597 noff = sizeof(struct ip6_hdr);
598 /* new mbuf contains only ipv6+icmpv6 headers */
599 n->m_len = noff + sizeof(struct icmp6_hdr);
600 /*
601 * Adjust mbuf. ip6_plen will be adjusted in
602 * ip6_output().
603 */
604 m_adj(n0, off + sizeof(struct icmp6_hdr));
605 /* recalculate complete packet size */
606 n->m_pkthdr.len = n0len + (noff - off);
607 n->m_next = n0;
608 } else {
609 nip6 = mtod(n, struct ip6_hdr *);
610 IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off,
611 sizeof(*nicmp6));
612 noff = off;
613 }
614 nicmp6->icmp6_type = ICMP6_ECHO_REPLY;
615 nicmp6->icmp6_code = 0;
616 if (n) {
617 ICMP6STAT_INC(icp6s_reflect);
618 ICMP6STAT_INC(icp6s_outhist[ICMP6_ECHO_REPLY]);
619 icmp6_reflect(n, noff);
620 }
621 break;
622
623 case ICMP6_ECHO_REPLY:
624 icmp6_ifstat_inc(ifp, ifs6_in_echoreply);
625 if (code != 0)
626 goto badcode;
627 break;
628
629 case MLD_LISTENER_QUERY:
630 case MLD_LISTENER_REPORT:
631 case MLD_LISTENER_DONE:
632 case MLDV2_LISTENER_REPORT:
633 /*
634 * Drop MLD traffic which is not link-local, has a hop limit
635 * of greater than 1 hop, or which does not have the
636 * IPv6 HBH Router Alert option.
637 * As IPv6 HBH options are stripped in ip6_input() we must
638 * check an mbuf header flag.
639 * XXX Should we also sanity check that these messages
640 * were directed to a link-local multicast prefix?
641 */
642 if ((ip6->ip6_hlim != 1) || (m->m_flags & M_RTALERT_MLD) == 0)
643 goto freeit;
644 if (mld_input(m, off, icmp6len) != 0)
645 return (IPPROTO_DONE);
646 /* m stays. */
647 break;
648
649 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */
650 {
651 enum { WRU, FQDN } mode;
652
653 if (!V_icmp6_nodeinfo)
654 break;
655
656 if (icmp6len == sizeof(struct icmp6_hdr) + 4)
657 mode = WRU;
658 else if (icmp6len >= sizeof(struct icmp6_nodeinfo))
659 mode = FQDN;
660 else
661 goto badlen;
662
663 if (mode == FQDN) {
664 #ifndef PULLDOWN_TEST
665 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo),
666 IPPROTO_DONE);
667 #endif
668 n = m_copy(m, 0, M_COPYALL);
669 if (n)
670 n = ni6_input(n, off);
671 /* XXX meaningless if n == NULL */
672 noff = sizeof(struct ip6_hdr);
673 } else {
674 struct prison *pr;
675 u_char *p;
676 int maxhlen, hlen;
677
678 /*
679 * XXX: this combination of flags is pointless,
680 * but should we keep this for compatibility?
681 */
682 if ((V_icmp6_nodeinfo & (ICMP6_NODEINFO_FQDNOK |
683 ICMP6_NODEINFO_TMPADDROK)) !=
684 (ICMP6_NODEINFO_FQDNOK | ICMP6_NODEINFO_TMPADDROK))
685 break;
686
687 if (code != 0)
688 goto badcode;
689
690 CTASSERT(sizeof(*nip6) + sizeof(*nicmp6) + 4 <= MHLEN);
691 n = m_gethdr(M_NOWAIT, m->m_type);
692 if (n == NULL) {
693 /* Give up remote */
694 break;
695 }
696 if (!m_dup_pkthdr(n, m, M_NOWAIT)) {
697 /*
698 * Previous code did a blind M_COPY_PKTHDR
699 * and said "just for rcvif". If true, then
700 * we could tolerate the dup failing (due to
701 * the deep copy of the tag chain). For now
702 * be conservative and just fail.
703 */
704 m_free(n);
705 n = NULL;
706 }
707 maxhlen = M_TRAILINGSPACE(n) -
708 (sizeof(*nip6) + sizeof(*nicmp6) + 4);
709 pr = curthread->td_ucred->cr_prison;
710 mtx_lock(&pr->pr_mtx);
711 hlen = strlen(pr->pr_hostname);
712 if (maxhlen > hlen)
713 maxhlen = hlen;
714 /*
715 * Copy IPv6 and ICMPv6 only.
716 */
717 nip6 = mtod(n, struct ip6_hdr *);
718 bcopy(ip6, nip6, sizeof(struct ip6_hdr));
719 nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
720 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
721 p = (u_char *)(nicmp6 + 1);
722 bzero(p, 4);
723 /* meaningless TTL */
724 bcopy(pr->pr_hostname, p + 4, maxhlen);
725 mtx_unlock(&pr->pr_mtx);
726 noff = sizeof(struct ip6_hdr);
727 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
728 sizeof(struct icmp6_hdr) + 4 + maxhlen;
729 nicmp6->icmp6_type = ICMP6_WRUREPLY;
730 nicmp6->icmp6_code = 0;
731 }
732 if (n) {
733 ICMP6STAT_INC(icp6s_reflect);
734 ICMP6STAT_INC(icp6s_outhist[ICMP6_WRUREPLY]);
735 icmp6_reflect(n, noff);
736 }
737 break;
738 }
739
740 case ICMP6_WRUREPLY:
741 if (code != 0)
742 goto badcode;
743 break;
744
745 case ND_ROUTER_SOLICIT:
746 icmp6_ifstat_inc(ifp, ifs6_in_routersolicit);
747 if (code != 0)
748 goto badcode;
749 if (icmp6len < sizeof(struct nd_router_solicit))
750 goto badlen;
751 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
752 /* give up local */
753
754 /* Send incoming SeND packet to user space. */
755 if (send_sendso_input_hook != NULL) {
756 IP6_EXTHDR_CHECK(m, off,
757 icmp6len, IPPROTO_DONE);
758 error = send_sendso_input_hook(m, ifp,
759 SND_IN, ip6len);
760 /* -1 == no app on SEND socket */
761 if (error == 0)
762 return (IPPROTO_DONE);
763 nd6_rs_input(m, off, icmp6len);
764 } else
765 nd6_rs_input(m, off, icmp6len);
766 m = NULL;
767 goto freeit;
768 }
769 if (send_sendso_input_hook != NULL) {
770 IP6_EXTHDR_CHECK(n, off,
771 icmp6len, IPPROTO_DONE);
772 error = send_sendso_input_hook(n, ifp,
773 SND_IN, ip6len);
774 if (error == 0)
775 goto freeit;
776 /* -1 == no app on SEND socket */
777 nd6_rs_input(n, off, icmp6len);
778 } else
779 nd6_rs_input(n, off, icmp6len);
780 /* m stays. */
781 break;
782
783 case ND_ROUTER_ADVERT:
784 icmp6_ifstat_inc(ifp, ifs6_in_routeradvert);
785 if (code != 0)
786 goto badcode;
787 if (icmp6len < sizeof(struct nd_router_advert))
788 goto badlen;
789 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
790
791 /* Send incoming SeND-protected/ND packet to user space. */
792 if (send_sendso_input_hook != NULL) {
793 error = send_sendso_input_hook(m, ifp,
794 SND_IN, ip6len);
795 if (error == 0)
796 return (IPPROTO_DONE);
797 nd6_ra_input(m, off, icmp6len);
798 } else
799 nd6_ra_input(m, off, icmp6len);
800 m = NULL;
801 goto freeit;
802 }
803 if (send_sendso_input_hook != NULL) {
804 error = send_sendso_input_hook(n, ifp,
805 SND_IN, ip6len);
806 if (error == 0)
807 goto freeit;
808 nd6_ra_input(n, off, icmp6len);
809 } else
810 nd6_ra_input(n, off, icmp6len);
811 /* m stays. */
812 break;
813
814 case ND_NEIGHBOR_SOLICIT:
815 icmp6_ifstat_inc(ifp, ifs6_in_neighborsolicit);
816 if (code != 0)
817 goto badcode;
818 if (icmp6len < sizeof(struct nd_neighbor_solicit))
819 goto badlen;
820 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
821 if (send_sendso_input_hook != NULL) {
822 error = send_sendso_input_hook(m, ifp,
823 SND_IN, ip6len);
824 if (error == 0)
825 return (IPPROTO_DONE);
826 nd6_ns_input(m, off, icmp6len);
827 } else
828 nd6_ns_input(m, off, icmp6len);
829 m = NULL;
830 goto freeit;
831 }
832 if (send_sendso_input_hook != NULL) {
833 error = send_sendso_input_hook(n, ifp,
834 SND_IN, ip6len);
835 if (error == 0)
836 goto freeit;
837 nd6_ns_input(n, off, icmp6len);
838 } else
839 nd6_ns_input(n, off, icmp6len);
840 /* m stays. */
841 break;
842
843 case ND_NEIGHBOR_ADVERT:
844 icmp6_ifstat_inc(ifp, ifs6_in_neighboradvert);
845 if (code != 0)
846 goto badcode;
847 if (icmp6len < sizeof(struct nd_neighbor_advert))
848 goto badlen;
849 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
850
851 /* Send incoming SeND-protected/ND packet to user space. */
852 if (send_sendso_input_hook != NULL) {
853 error = send_sendso_input_hook(m, ifp,
854 SND_IN, ip6len);
855 if (error == 0)
856 return (IPPROTO_DONE);
857 nd6_na_input(m, off, icmp6len);
858 } else
859 nd6_na_input(m, off, icmp6len);
860 m = NULL;
861 goto freeit;
862 }
863 if (send_sendso_input_hook != NULL) {
864 error = send_sendso_input_hook(n, ifp,
865 SND_IN, ip6len);
866 if (error == 0)
867 goto freeit;
868 nd6_na_input(n, off, icmp6len);
869 } else
870 nd6_na_input(n, off, icmp6len);
871 /* m stays. */
872 break;
873
874 case ND_REDIRECT:
875 icmp6_ifstat_inc(ifp, ifs6_in_redirect);
876 if (code != 0)
877 goto badcode;
878 if (icmp6len < sizeof(struct nd_redirect))
879 goto badlen;
880 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
881 if (send_sendso_input_hook != NULL) {
882 error = send_sendso_input_hook(m, ifp,
883 SND_IN, ip6len);
884 if (error == 0)
885 return (IPPROTO_DONE);
886 icmp6_redirect_input(m, off);
887 } else
888 icmp6_redirect_input(m, off);
889 m = NULL;
890 goto freeit;
891 }
892 if (send_sendso_input_hook != NULL) {
893 error = send_sendso_input_hook(n, ifp,
894 SND_IN, ip6len);
895 if (error == 0)
896 goto freeit;
897 icmp6_redirect_input(n, off);
898 } else
899 icmp6_redirect_input(n, off);
900 /* m stays. */
901 break;
902
903 case ICMP6_ROUTER_RENUMBERING:
904 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND &&
905 code != ICMP6_ROUTER_RENUMBERING_RESULT)
906 goto badcode;
907 if (icmp6len < sizeof(struct icmp6_router_renum))
908 goto badlen;
909 break;
910
911 default:
912 nd6log((LOG_DEBUG,
913 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n",
914 icmp6->icmp6_type, ip6_sprintf(ip6bufs, &ip6->ip6_src),
915 ip6_sprintf(ip6bufd, &ip6->ip6_dst),
916 ifp ? ifp->if_index : 0));
917 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) {
918 /* ICMPv6 error: MUST deliver it by spec... */
919 code = PRC_NCMDS;
920 /* deliver */
921 } else {
922 /* ICMPv6 informational: MUST not deliver */
923 break;
924 }
925 deliver:
926 if (icmp6_notify_error(&m, off, icmp6len, code) != 0) {
927 /* In this case, m should've been freed. */
928 return (IPPROTO_DONE);
929 }
930 break;
931
932 badcode:
933 ICMP6STAT_INC(icp6s_badcode);
934 break;
935
936 badlen:
937 ICMP6STAT_INC(icp6s_badlen);
938 break;
939 }
940
941 /* deliver the packet to appropriate sockets */
942 icmp6_rip6_input(&m, *offp);
943
944 return IPPROTO_DONE;
945
946 freeit:
947 m_freem(m);
948 return IPPROTO_DONE;
949 }
950
951 static int
952 icmp6_notify_error(struct mbuf **mp, int off, int icmp6len, int code)
953 {
954 struct mbuf *m = *mp;
955 struct icmp6_hdr *icmp6;
956 struct ip6_hdr *eip6;
957 u_int32_t notifymtu;
958 struct sockaddr_in6 icmp6src, icmp6dst;
959
960 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) {
961 ICMP6STAT_INC(icp6s_tooshort);
962 goto freeit;
963 }
964 #ifndef PULLDOWN_TEST
965 IP6_EXTHDR_CHECK(m, off,
966 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1);
967 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
968 #else
969 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
970 sizeof(*icmp6) + sizeof(struct ip6_hdr));
971 if (icmp6 == NULL) {
972 ICMP6STAT_INC(icp6s_tooshort);
973 return (-1);
974 }
975 #endif
976 eip6 = (struct ip6_hdr *)(icmp6 + 1);
977
978 /* Detect the upper level protocol */
979 {
980 void (*ctlfunc)(int, struct sockaddr *, void *);
981 u_int8_t nxt = eip6->ip6_nxt;
982 int eoff = off + sizeof(struct icmp6_hdr) +
983 sizeof(struct ip6_hdr);
984 struct ip6ctlparam ip6cp;
985 struct in6_addr *finaldst = NULL;
986 int icmp6type = icmp6->icmp6_type;
987 struct ip6_frag *fh;
988 struct ip6_rthdr *rth;
989 struct ip6_rthdr0 *rth0;
990 int rthlen;
991
992 while (1) { /* XXX: should avoid infinite loop explicitly? */
993 struct ip6_ext *eh;
994
995 switch (nxt) {
996 case IPPROTO_HOPOPTS:
997 case IPPROTO_DSTOPTS:
998 case IPPROTO_AH:
999 #ifndef PULLDOWN_TEST
1000 IP6_EXTHDR_CHECK(m, 0,
1001 eoff + sizeof(struct ip6_ext), -1);
1002 eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff);
1003 #else
1004 IP6_EXTHDR_GET(eh, struct ip6_ext *, m,
1005 eoff, sizeof(*eh));
1006 if (eh == NULL) {
1007 ICMP6STAT_INC(icp6s_tooshort);
1008 return (-1);
1009 }
1010 #endif
1011
1012 if (nxt == IPPROTO_AH)
1013 eoff += (eh->ip6e_len + 2) << 2;
1014 else
1015 eoff += (eh->ip6e_len + 1) << 3;
1016 nxt = eh->ip6e_nxt;
1017 break;
1018 case IPPROTO_ROUTING:
1019 /*
1020 * When the erroneous packet contains a
1021 * routing header, we should examine the
1022 * header to determine the final destination.
1023 * Otherwise, we can't properly update
1024 * information that depends on the final
1025 * destination (e.g. path MTU).
1026 */
1027 #ifndef PULLDOWN_TEST
1028 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1);
1029 rth = (struct ip6_rthdr *)
1030 (mtod(m, caddr_t) + eoff);
1031 #else
1032 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m,
1033 eoff, sizeof(*rth));
1034 if (rth == NULL) {
1035 ICMP6STAT_INC(icp6s_tooshort);
1036 return (-1);
1037 }
1038 #endif
1039 rthlen = (rth->ip6r_len + 1) << 3;
1040 /*
1041 * XXX: currently there is no
1042 * officially defined type other
1043 * than type-0.
1044 * Note that if the segment left field
1045 * is 0, all intermediate hops must
1046 * have been passed.
1047 */
1048 if (rth->ip6r_segleft &&
1049 rth->ip6r_type == IPV6_RTHDR_TYPE_0) {
1050 int hops;
1051
1052 #ifndef PULLDOWN_TEST
1053 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1);
1054 rth0 = (struct ip6_rthdr0 *)
1055 (mtod(m, caddr_t) + eoff);
1056 #else
1057 IP6_EXTHDR_GET(rth0,
1058 struct ip6_rthdr0 *, m,
1059 eoff, rthlen);
1060 if (rth0 == NULL) {
1061 ICMP6STAT_INC(icp6s_tooshort);
1062 return (-1);
1063 }
1064 #endif
1065 /* just ignore a bogus header */
1066 if ((rth0->ip6r0_len % 2) == 0 &&
1067 (hops = rth0->ip6r0_len/2))
1068 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1);
1069 }
1070 eoff += rthlen;
1071 nxt = rth->ip6r_nxt;
1072 break;
1073 case IPPROTO_FRAGMENT:
1074 #ifndef PULLDOWN_TEST
1075 IP6_EXTHDR_CHECK(m, 0, eoff +
1076 sizeof(struct ip6_frag), -1);
1077 fh = (struct ip6_frag *)(mtod(m, caddr_t) +
1078 eoff);
1079 #else
1080 IP6_EXTHDR_GET(fh, struct ip6_frag *, m,
1081 eoff, sizeof(*fh));
1082 if (fh == NULL) {
1083 ICMP6STAT_INC(icp6s_tooshort);
1084 return (-1);
1085 }
1086 #endif
1087 /*
1088 * Data after a fragment header is meaningless
1089 * unless it is the first fragment, but
1090 * we'll go to the notify label for path MTU
1091 * discovery.
1092 */
1093 if (fh->ip6f_offlg & IP6F_OFF_MASK)
1094 goto notify;
1095
1096 eoff += sizeof(struct ip6_frag);
1097 nxt = fh->ip6f_nxt;
1098 break;
1099 default:
1100 /*
1101 * This case includes ESP and the No Next
1102 * Header. In such cases going to the notify
1103 * label does not have any meaning
1104 * (i.e. ctlfunc will be NULL), but we go
1105 * anyway since we might have to update
1106 * path MTU information.
1107 */
1108 goto notify;
1109 }
1110 }
1111 notify:
1112 #ifndef PULLDOWN_TEST
1113 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
1114 #else
1115 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
1116 sizeof(*icmp6) + sizeof(struct ip6_hdr));
1117 if (icmp6 == NULL) {
1118 ICMP6STAT_INC(icp6s_tooshort);
1119 return (-1);
1120 }
1121 #endif
1122
1123 /*
1124 * retrieve parameters from the inner IPv6 header, and convert
1125 * them into sockaddr structures.
1126 * XXX: there is no guarantee that the source or destination
1127 * addresses of the inner packet are in the same scope as
1128 * the addresses of the icmp packet. But there is no other
1129 * way to determine the zone.
1130 */
1131 eip6 = (struct ip6_hdr *)(icmp6 + 1);
1132
1133 bzero(&icmp6dst, sizeof(icmp6dst));
1134 icmp6dst.sin6_len = sizeof(struct sockaddr_in6);
1135 icmp6dst.sin6_family = AF_INET6;
1136 if (finaldst == NULL)
1137 icmp6dst.sin6_addr = eip6->ip6_dst;
1138 else
1139 icmp6dst.sin6_addr = *finaldst;
1140 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL))
1141 goto freeit;
1142 bzero(&icmp6src, sizeof(icmp6src));
1143 icmp6src.sin6_len = sizeof(struct sockaddr_in6);
1144 icmp6src.sin6_family = AF_INET6;
1145 icmp6src.sin6_addr = eip6->ip6_src;
1146 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL))
1147 goto freeit;
1148 icmp6src.sin6_flowinfo =
1149 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK);
1150
1151 if (finaldst == NULL)
1152 finaldst = &eip6->ip6_dst;
1153 ip6cp.ip6c_m = m;
1154 ip6cp.ip6c_icmp6 = icmp6;
1155 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1);
1156 ip6cp.ip6c_off = eoff;
1157 ip6cp.ip6c_finaldst = finaldst;
1158 ip6cp.ip6c_src = &icmp6src;
1159 ip6cp.ip6c_nxt = nxt;
1160
1161 if (icmp6type == ICMP6_PACKET_TOO_BIG) {
1162 notifymtu = ntohl(icmp6->icmp6_mtu);
1163 ip6cp.ip6c_cmdarg = (void *)¬ifymtu;
1164 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/
1165 }
1166
1167 ctlfunc = (void (*)(int, struct sockaddr *, void *))
1168 (inet6sw[ip6_protox[nxt]].pr_ctlinput);
1169 if (ctlfunc) {
1170 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst,
1171 &ip6cp);
1172 }
1173 }
1174 *mp = m;
1175 return (0);
1176
1177 freeit:
1178 m_freem(m);
1179 return (-1);
1180 }
1181
1182 void
1183 icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated)
1184 {
1185 struct in6_addr *dst = ip6cp->ip6c_finaldst;
1186 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6;
1187 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */
1188 u_int mtu = ntohl(icmp6->icmp6_mtu);
1189 struct in_conninfo inc;
1190
1191 #if 0
1192 /*
1193 * RFC2460 section 5, last paragraph.
1194 * even though minimum link MTU for IPv6 is IPV6_MMTU,
1195 * we may see ICMPv6 too big with mtu < IPV6_MMTU
1196 * due to packet translator in the middle.
1197 * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for
1198 * special handling.
1199 */
1200 if (mtu < IPV6_MMTU)
1201 return;
1202 #endif
1203
1204 /*
1205 * we reject ICMPv6 too big with abnormally small value.
1206 * XXX what is the good definition of "abnormally small"?
1207 */
1208 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8)
1209 return;
1210
1211 if (!validated)
1212 return;
1213
1214 /*
1215 * In case the suggested mtu is less than IPV6_MMTU, we
1216 * only need to remember that it was for above mentioned
1217 * "alwaysfrag" case.
1218 * Try to be as close to the spec as possible.
1219 */
1220 if (mtu < IPV6_MMTU)
1221 mtu = IPV6_MMTU - 8;
1222
1223 bzero(&inc, sizeof(inc));
1224 inc.inc_fibnum = M_GETFIB(m);
1225 inc.inc_flags |= INC_ISIPV6;
1226 inc.inc6_faddr = *dst;
1227 if (in6_setscope(&inc.inc6_faddr, m->m_pkthdr.rcvif, NULL))
1228 return;
1229
1230 if (mtu < tcp_maxmtu6(&inc, NULL)) {
1231 tcp_hc_updatemtu(&inc, mtu);
1232 ICMP6STAT_INC(icp6s_pmtuchg);
1233 }
1234 }
1235
1236 /*
1237 * Process a Node Information Query packet, based on
1238 * draft-ietf-ipngwg-icmp-name-lookups-07.
1239 *
1240 * Spec incompatibilities:
1241 * - IPv6 Subject address handling
1242 * - IPv4 Subject address handling support missing
1243 * - Proxy reply (answer even if it's not for me)
1244 * - joins NI group address at in6_ifattach() time only, does not cope
1245 * with hostname changes by sethostname(3)
1246 */
1247 static struct mbuf *
1248 ni6_input(struct mbuf *m, int off)
1249 {
1250 struct icmp6_nodeinfo *ni6, *nni6;
1251 struct mbuf *n = NULL;
1252 struct prison *pr;
1253 u_int16_t qtype;
1254 int subjlen;
1255 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
1256 struct ni_reply_fqdn *fqdn;
1257 int addrs; /* for NI_QTYPE_NODEADDR */
1258 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */
1259 struct in6_addr in6_subj; /* subject address */
1260 struct ip6_hdr *ip6;
1261 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */
1262 char *subj = NULL;
1263 struct in6_ifaddr *ia6 = NULL;
1264
1265 ip6 = mtod(m, struct ip6_hdr *);
1266 #ifndef PULLDOWN_TEST
1267 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off);
1268 #else
1269 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6));
1270 if (ni6 == NULL) {
1271 /* m is already reclaimed */
1272 return (NULL);
1273 }
1274 #endif
1275
1276 /*
1277 * Validate IPv6 source address.
1278 * The default configuration MUST be to refuse answering queries from
1279 * global-scope addresses according to RFC4602.
1280 * Notes:
1281 * - it's not very clear what "refuse" means; this implementation
1282 * simply drops it.
1283 * - it's not very easy to identify global-scope (unicast) addresses
1284 * since there are many prefixes for them. It should be safer
1285 * and in practice sufficient to check "all" but loopback and
1286 * link-local (note that site-local unicast was deprecated and
1287 * ULA is defined as global scope-wise)
1288 */
1289 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_GLOBALOK) == 0 &&
1290 !IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) &&
1291 !IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src))
1292 goto bad;
1293
1294 /*
1295 * Validate IPv6 destination address.
1296 *
1297 * The Responder must discard the Query without further processing
1298 * unless it is one of the Responder's unicast or anycast addresses, or
1299 * a link-local scope multicast address which the Responder has joined.
1300 * [RFC4602, Section 5.]
1301 */
1302 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
1303 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst))
1304 goto bad;
1305 /* else it's a link-local multicast, fine */
1306 } else { /* unicast or anycast */
1307 if ((ia6 = ip6_getdstifaddr(m)) == NULL)
1308 goto bad; /* XXX impossible */
1309
1310 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) &&
1311 !(V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK)) {
1312 ifa_free(&ia6->ia_ifa);
1313 nd6log((LOG_DEBUG, "ni6_input: ignore node info to "
1314 "a temporary address in %s:%d",
1315 __FILE__, __LINE__));
1316 goto bad;
1317 }
1318 ifa_free(&ia6->ia_ifa);
1319 }
1320
1321 /* validate query Subject field. */
1322 qtype = ntohs(ni6->ni_qtype);
1323 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo);
1324 switch (qtype) {
1325 case NI_QTYPE_NOOP:
1326 case NI_QTYPE_SUPTYPES:
1327 /* 07 draft */
1328 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0)
1329 break;
1330 /* FALLTHROUGH */
1331 case NI_QTYPE_FQDN:
1332 case NI_QTYPE_NODEADDR:
1333 case NI_QTYPE_IPV4ADDR:
1334 switch (ni6->ni_code) {
1335 case ICMP6_NI_SUBJ_IPV6:
1336 #if ICMP6_NI_SUBJ_IPV6 != 0
1337 case 0:
1338 #endif
1339 /*
1340 * backward compatibility - try to accept 03 draft
1341 * format, where no Subject is present.
1342 */
1343 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 &&
1344 subjlen == 0) {
1345 oldfqdn++;
1346 break;
1347 }
1348 #if ICMP6_NI_SUBJ_IPV6 != 0
1349 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6)
1350 goto bad;
1351 #endif
1352
1353 if (subjlen != sizeof(struct in6_addr))
1354 goto bad;
1355
1356 /*
1357 * Validate Subject address.
1358 *
1359 * Not sure what exactly "address belongs to the node"
1360 * means in the spec, is it just unicast, or what?
1361 *
1362 * At this moment we consider Subject address as
1363 * "belong to the node" if the Subject address equals
1364 * to the IPv6 destination address; validation for
1365 * IPv6 destination address should have done enough
1366 * check for us.
1367 *
1368 * We do not do proxy at this moment.
1369 */
1370 /* m_pulldown instead of copy? */
1371 m_copydata(m, off + sizeof(struct icmp6_nodeinfo),
1372 subjlen, (caddr_t)&in6_subj);
1373 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL))
1374 goto bad;
1375
1376 subj = (char *)&in6_subj;
1377 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj))
1378 break;
1379
1380 /*
1381 * XXX if we are to allow other cases, we should really
1382 * be careful about scope here.
1383 * basically, we should disallow queries toward IPv6
1384 * destination X with subject Y,
1385 * if scope(X) > scope(Y).
1386 * if we allow scope(X) > scope(Y), it will result in
1387 * information leakage across scope boundary.
1388 */
1389 goto bad;
1390
1391 case ICMP6_NI_SUBJ_FQDN:
1392 /*
1393 * Validate Subject name with gethostname(3).
1394 *
1395 * The behavior may need some debate, since:
1396 * - we are not sure if the node has FQDN as
1397 * hostname (returned by gethostname(3)).
1398 * - the code does wildcard match for truncated names.
1399 * however, we are not sure if we want to perform
1400 * wildcard match, if gethostname(3) side has
1401 * truncated hostname.
1402 */
1403 pr = curthread->td_ucred->cr_prison;
1404 mtx_lock(&pr->pr_mtx);
1405 n = ni6_nametodns(pr->pr_hostname,
1406 strlen(pr->pr_hostname), 0);
1407 mtx_unlock(&pr->pr_mtx);
1408 if (!n || n->m_next || n->m_len == 0)
1409 goto bad;
1410 IP6_EXTHDR_GET(subj, char *, m,
1411 off + sizeof(struct icmp6_nodeinfo), subjlen);
1412 if (subj == NULL)
1413 goto bad;
1414 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *),
1415 n->m_len)) {
1416 goto bad;
1417 }
1418 m_freem(n);
1419 n = NULL;
1420 break;
1421
1422 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */
1423 default:
1424 goto bad;
1425 }
1426 break;
1427 }
1428
1429 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */
1430 switch (qtype) {
1431 case NI_QTYPE_FQDN:
1432 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_FQDNOK) == 0)
1433 goto bad;
1434 break;
1435 case NI_QTYPE_NODEADDR:
1436 case NI_QTYPE_IPV4ADDR:
1437 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_NODEADDROK) == 0)
1438 goto bad;
1439 break;
1440 }
1441
1442 /* guess reply length */
1443 switch (qtype) {
1444 case NI_QTYPE_NOOP:
1445 break; /* no reply data */
1446 case NI_QTYPE_SUPTYPES:
1447 replylen += sizeof(u_int32_t);
1448 break;
1449 case NI_QTYPE_FQDN:
1450 /* XXX will append an mbuf */
1451 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1452 break;
1453 case NI_QTYPE_NODEADDR:
1454 addrs = ni6_addrs(ni6, m, &ifp, (struct in6_addr *)subj);
1455 if ((replylen += addrs * (sizeof(struct in6_addr) +
1456 sizeof(u_int32_t))) > MCLBYTES)
1457 replylen = MCLBYTES; /* XXX: will truncate pkt later */
1458 break;
1459 case NI_QTYPE_IPV4ADDR:
1460 /* unsupported - should respond with unknown Qtype? */
1461 break;
1462 default:
1463 /*
1464 * XXX: We must return a reply with the ICMP6 code
1465 * `unknown Qtype' in this case. However we regard the case
1466 * as an FQDN query for backward compatibility.
1467 * Older versions set a random value to this field,
1468 * so it rarely varies in the defined qtypes.
1469 * But the mechanism is not reliable...
1470 * maybe we should obsolete older versions.
1471 */
1472 qtype = NI_QTYPE_FQDN;
1473 /* XXX will append an mbuf */
1474 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1475 oldfqdn++;
1476 break;
1477 }
1478
1479 /* Allocate an mbuf to reply. */
1480 if (replylen > MCLBYTES) {
1481 /*
1482 * XXX: should we try to allocate more? But MCLBYTES
1483 * is probably much larger than IPV6_MMTU...
1484 */
1485 goto bad;
1486 }
1487 if (replylen > MHLEN)
1488 n = m_getcl(M_NOWAIT, m->m_type, M_PKTHDR);
1489 else
1490 n = m_gethdr(M_NOWAIT, m->m_type);
1491 if (n == NULL) {
1492 m_freem(m);
1493 return (NULL);
1494 }
1495 m_move_pkthdr(n, m); /* just for recvif and FIB */
1496 n->m_pkthdr.len = n->m_len = replylen;
1497
1498 /* copy mbuf header and IPv6 + Node Information base headers */
1499 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr));
1500 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1);
1501 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo));
1502
1503 /* qtype dependent procedure */
1504 switch (qtype) {
1505 case NI_QTYPE_NOOP:
1506 nni6->ni_code = ICMP6_NI_SUCCESS;
1507 nni6->ni_flags = 0;
1508 break;
1509 case NI_QTYPE_SUPTYPES:
1510 {
1511 u_int32_t v;
1512 nni6->ni_code = ICMP6_NI_SUCCESS;
1513 nni6->ni_flags = htons(0x0000); /* raw bitmap */
1514 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */
1515 v = (u_int32_t)htonl(0x0000000f);
1516 bcopy(&v, nni6 + 1, sizeof(u_int32_t));
1517 break;
1518 }
1519 case NI_QTYPE_FQDN:
1520 nni6->ni_code = ICMP6_NI_SUCCESS;
1521 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) +
1522 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo));
1523 nni6->ni_flags = 0; /* XXX: meaningless TTL */
1524 fqdn->ni_fqdn_ttl = 0; /* ditto. */
1525 /*
1526 * XXX do we really have FQDN in hostname?
1527 */
1528 pr = curthread->td_ucred->cr_prison;
1529 mtx_lock(&pr->pr_mtx);
1530 n->m_next = ni6_nametodns(pr->pr_hostname,
1531 strlen(pr->pr_hostname), oldfqdn);
1532 mtx_unlock(&pr->pr_mtx);
1533 if (n->m_next == NULL)
1534 goto bad;
1535 /* XXX we assume that n->m_next is not a chain */
1536 if (n->m_next->m_next != NULL)
1537 goto bad;
1538 n->m_pkthdr.len += n->m_next->m_len;
1539 break;
1540 case NI_QTYPE_NODEADDR:
1541 {
1542 int lenlim, copied;
1543
1544 nni6->ni_code = ICMP6_NI_SUCCESS;
1545 n->m_pkthdr.len = n->m_len =
1546 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
1547 lenlim = M_TRAILINGSPACE(n);
1548 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim);
1549 /* XXX: reset mbuf length */
1550 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
1551 sizeof(struct icmp6_nodeinfo) + copied;
1552 break;
1553 }
1554 default:
1555 break; /* XXX impossible! */
1556 }
1557
1558 nni6->ni_type = ICMP6_NI_REPLY;
1559 m_freem(m);
1560 return (n);
1561
1562 bad:
1563 m_freem(m);
1564 if (n)
1565 m_freem(n);
1566 return (NULL);
1567 }
1568
1569 /*
1570 * make a mbuf with DNS-encoded string. no compression support.
1571 *
1572 * XXX names with less than 2 dots (like "foo" or "foo.section") will be
1573 * treated as truncated name (two \0 at the end). this is a wild guess.
1574 *
1575 * old - return pascal string if non-zero
1576 */
1577 static struct mbuf *
1578 ni6_nametodns(const char *name, int namelen, int old)
1579 {
1580 struct mbuf *m;
1581 char *cp, *ep;
1582 const char *p, *q;
1583 int i, len, nterm;
1584
1585 if (old)
1586 len = namelen + 1;
1587 else
1588 len = MCLBYTES;
1589
1590 /* Because MAXHOSTNAMELEN is usually 256, we use cluster mbuf. */
1591 if (len > MLEN)
1592 m = m_getcl(M_NOWAIT, MT_DATA, 0);
1593 else
1594 m = m_get(M_NOWAIT, MT_DATA);
1595 if (m == NULL)
1596 goto fail;
1597
1598 if (old) {
1599 m->m_len = len;
1600 *mtod(m, char *) = namelen;
1601 bcopy(name, mtod(m, char *) + 1, namelen);
1602 return m;
1603 } else {
1604 m->m_len = 0;
1605 cp = mtod(m, char *);
1606 ep = mtod(m, char *) + M_TRAILINGSPACE(m);
1607
1608 /* if not certain about my name, return empty buffer */
1609 if (namelen == 0)
1610 return m;
1611
1612 /*
1613 * guess if it looks like shortened hostname, or FQDN.
1614 * shortened hostname needs two trailing "\0".
1615 */
1616 i = 0;
1617 for (p = name; p < name + namelen; p++) {
1618 if (*p && *p == '.')
1619 i++;
1620 }
1621 if (i < 2)
1622 nterm = 2;
1623 else
1624 nterm = 1;
1625
1626 p = name;
1627 while (cp < ep && p < name + namelen) {
1628 i = 0;
1629 for (q = p; q < name + namelen && *q && *q != '.'; q++)
1630 i++;
1631 /* result does not fit into mbuf */
1632 if (cp + i + 1 >= ep)
1633 goto fail;
1634 /*
1635 * DNS label length restriction, RFC1035 page 8.
1636 * "i == 0" case is included here to avoid returning
1637 * 0-length label on "foo..bar".
1638 */
1639 if (i <= 0 || i >= 64)
1640 goto fail;
1641 *cp++ = i;
1642 bcopy(p, cp, i);
1643 cp += i;
1644 p = q;
1645 if (p < name + namelen && *p == '.')
1646 p++;
1647 }
1648 /* termination */
1649 if (cp + nterm >= ep)
1650 goto fail;
1651 while (nterm-- > 0)
1652 *cp++ = '\0';
1653 m->m_len = cp - mtod(m, char *);
1654 return m;
1655 }
1656
1657 panic("should not reach here");
1658 /* NOTREACHED */
1659
1660 fail:
1661 if (m)
1662 m_freem(m);
1663 return NULL;
1664 }
1665
1666 /*
1667 * check if two DNS-encoded string matches. takes care of truncated
1668 * form (with \0\0 at the end). no compression support.
1669 * XXX upper/lowercase match (see RFC2065)
1670 */
1671 static int
1672 ni6_dnsmatch(const char *a, int alen, const char *b, int blen)
1673 {
1674 const char *a0, *b0;
1675 int l;
1676
1677 /* simplest case - need validation? */
1678 if (alen == blen && bcmp(a, b, alen) == 0)
1679 return 1;
1680
1681 a0 = a;
1682 b0 = b;
1683
1684 /* termination is mandatory */
1685 if (alen < 2 || blen < 2)
1686 return 0;
1687 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0')
1688 return 0;
1689 alen--;
1690 blen--;
1691
1692 while (a - a0 < alen && b - b0 < blen) {
1693 if (a - a0 + 1 > alen || b - b0 + 1 > blen)
1694 return 0;
1695
1696 if ((signed char)a[0] < 0 || (signed char)b[0] < 0)
1697 return 0;
1698 /* we don't support compression yet */
1699 if (a[0] >= 64 || b[0] >= 64)
1700 return 0;
1701
1702 /* truncated case */
1703 if (a[0] == 0 && a - a0 == alen - 1)
1704 return 1;
1705 if (b[0] == 0 && b - b0 == blen - 1)
1706 return 1;
1707 if (a[0] == 0 || b[0] == 0)
1708 return 0;
1709
1710 if (a[0] != b[0])
1711 return 0;
1712 l = a[0];
1713 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen)
1714 return 0;
1715 if (bcmp(a + 1, b + 1, l) != 0)
1716 return 0;
1717
1718 a += 1 + l;
1719 b += 1 + l;
1720 }
1721
1722 if (a - a0 == alen && b - b0 == blen)
1723 return 1;
1724 else
1725 return 0;
1726 }
1727
1728 /*
1729 * calculate the number of addresses to be returned in the node info reply.
1730 */
1731 static int
1732 ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, struct ifnet **ifpp,
1733 struct in6_addr *subj)
1734 {
1735 struct ifnet *ifp;
1736 struct in6_ifaddr *ifa6;
1737 struct ifaddr *ifa;
1738 int addrs = 0, addrsofif, iffound = 0;
1739 int niflags = ni6->ni_flags;
1740
1741 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) {
1742 switch (ni6->ni_code) {
1743 case ICMP6_NI_SUBJ_IPV6:
1744 if (subj == NULL) /* must be impossible... */
1745 return (0);
1746 break;
1747 default:
1748 /*
1749 * XXX: we only support IPv6 subject address for
1750 * this Qtype.
1751 */
1752 return (0);
1753 }
1754 }
1755
1756 IFNET_RLOCK_NOSLEEP();
1757 TAILQ_FOREACH(ifp, &V_ifnet, if_list) {
1758 addrsofif = 0;
1759 IF_ADDR_RLOCK(ifp);
1760 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1761 if (ifa->ifa_addr->sa_family != AF_INET6)
1762 continue;
1763 ifa6 = (struct in6_ifaddr *)ifa;
1764
1765 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 &&
1766 IN6_ARE_ADDR_EQUAL(subj, &ifa6->ia_addr.sin6_addr))
1767 iffound = 1;
1768
1769 /*
1770 * IPv4-mapped addresses can only be returned by a
1771 * Node Information proxy, since they represent
1772 * addresses of IPv4-only nodes, which perforce do
1773 * not implement this protocol.
1774 * [icmp-name-lookups-07, Section 5.4]
1775 * So we don't support NI_NODEADDR_FLAG_COMPAT in
1776 * this function at this moment.
1777 */
1778
1779 /* What do we have to do about ::1? */
1780 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
1781 case IPV6_ADDR_SCOPE_LINKLOCAL:
1782 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
1783 continue;
1784 break;
1785 case IPV6_ADDR_SCOPE_SITELOCAL:
1786 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
1787 continue;
1788 break;
1789 case IPV6_ADDR_SCOPE_GLOBAL:
1790 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
1791 continue;
1792 break;
1793 default:
1794 continue;
1795 }
1796
1797 /*
1798 * check if anycast is okay.
1799 * XXX: just experimental. not in the spec.
1800 */
1801 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 &&
1802 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0)
1803 continue; /* we need only unicast addresses */
1804 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
1805 (V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) {
1806 continue;
1807 }
1808 addrsofif++; /* count the address */
1809 }
1810 IF_ADDR_RUNLOCK(ifp);
1811 if (iffound) {
1812 *ifpp = ifp;
1813 IFNET_RUNLOCK_NOSLEEP();
1814 return (addrsofif);
1815 }
1816
1817 addrs += addrsofif;
1818 }
1819 IFNET_RUNLOCK_NOSLEEP();
1820
1821 return (addrs);
1822 }
1823
1824 static int
1825 ni6_store_addrs(struct icmp6_nodeinfo *ni6, struct icmp6_nodeinfo *nni6,
1826 struct ifnet *ifp0, int resid)
1827 {
1828 struct ifnet *ifp;
1829 struct in6_ifaddr *ifa6;
1830 struct ifaddr *ifa;
1831 struct ifnet *ifp_dep = NULL;
1832 int copied = 0, allow_deprecated = 0;
1833 u_char *cp = (u_char *)(nni6 + 1);
1834 int niflags = ni6->ni_flags;
1835 u_int32_t ltime;
1836
1837 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL))
1838 return (0); /* needless to copy */
1839
1840 IFNET_RLOCK_NOSLEEP();
1841 ifp = ifp0 ? ifp0 : TAILQ_FIRST(&V_ifnet);
1842 again:
1843
1844 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) {
1845 IF_ADDR_RLOCK(ifp);
1846 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1847 if (ifa->ifa_addr->sa_family != AF_INET6)
1848 continue;
1849 ifa6 = (struct in6_ifaddr *)ifa;
1850
1851 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 &&
1852 allow_deprecated == 0) {
1853 /*
1854 * prefererred address should be put before
1855 * deprecated addresses.
1856 */
1857
1858 /* record the interface for later search */
1859 if (ifp_dep == NULL)
1860 ifp_dep = ifp;
1861
1862 continue;
1863 } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 &&
1864 allow_deprecated != 0)
1865 continue; /* we now collect deprecated addrs */
1866
1867 /* What do we have to do about ::1? */
1868 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
1869 case IPV6_ADDR_SCOPE_LINKLOCAL:
1870 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
1871 continue;
1872 break;
1873 case IPV6_ADDR_SCOPE_SITELOCAL:
1874 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
1875 continue;
1876 break;
1877 case IPV6_ADDR_SCOPE_GLOBAL:
1878 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
1879 continue;
1880 break;
1881 default:
1882 continue;
1883 }
1884
1885 /*
1886 * check if anycast is okay.
1887 * XXX: just experimental. not in the spec.
1888 */
1889 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 &&
1890 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0)
1891 continue;
1892 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
1893 (V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) {
1894 continue;
1895 }
1896
1897 /* now we can copy the address */
1898 if (resid < sizeof(struct in6_addr) +
1899 sizeof(u_int32_t)) {
1900 IF_ADDR_RUNLOCK(ifp);
1901 /*
1902 * We give up much more copy.
1903 * Set the truncate flag and return.
1904 */
1905 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE;
1906 IFNET_RUNLOCK_NOSLEEP();
1907 return (copied);
1908 }
1909
1910 /*
1911 * Set the TTL of the address.
1912 * The TTL value should be one of the following
1913 * according to the specification:
1914 *
1915 * 1. The remaining lifetime of a DHCP lease on the
1916 * address, or
1917 * 2. The remaining Valid Lifetime of a prefix from
1918 * which the address was derived through Stateless
1919 * Autoconfiguration.
1920 *
1921 * Note that we currently do not support stateful
1922 * address configuration by DHCPv6, so the former
1923 * case can't happen.
1924 */
1925 if (ifa6->ia6_lifetime.ia6t_expire == 0)
1926 ltime = ND6_INFINITE_LIFETIME;
1927 else {
1928 if (ifa6->ia6_lifetime.ia6t_expire >
1929 time_uptime)
1930 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_uptime);
1931 else
1932 ltime = 0;
1933 }
1934
1935 bcopy(<ime, cp, sizeof(u_int32_t));
1936 cp += sizeof(u_int32_t);
1937
1938 /* copy the address itself */
1939 bcopy(&ifa6->ia_addr.sin6_addr, cp,
1940 sizeof(struct in6_addr));
1941 in6_clearscope((struct in6_addr *)cp); /* XXX */
1942 cp += sizeof(struct in6_addr);
1943
1944 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t));
1945 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t));
1946 }
1947 IF_ADDR_RUNLOCK(ifp);
1948 if (ifp0) /* we need search only on the specified IF */
1949 break;
1950 }
1951
1952 if (allow_deprecated == 0 && ifp_dep != NULL) {
1953 ifp = ifp_dep;
1954 allow_deprecated = 1;
1955
1956 goto again;
1957 }
1958
1959 IFNET_RUNLOCK_NOSLEEP();
1960
1961 return (copied);
1962 }
1963
1964 /*
1965 * XXX almost dup'ed code with rip6_input.
1966 */
1967 static int
1968 icmp6_rip6_input(struct mbuf **mp, int off)
1969 {
1970 struct mbuf *m = *mp;
1971 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1972 struct inpcb *in6p;
1973 struct inpcb *last = NULL;
1974 struct sockaddr_in6 fromsa;
1975 struct icmp6_hdr *icmp6;
1976 struct mbuf *opts = NULL;
1977
1978 #ifndef PULLDOWN_TEST
1979 /* this is assumed to be safe. */
1980 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
1981 #else
1982 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
1983 if (icmp6 == NULL) {
1984 /* m is already reclaimed */
1985 return (IPPROTO_DONE);
1986 }
1987 #endif
1988
1989 /*
1990 * XXX: the address may have embedded scope zone ID, which should be
1991 * hidden from applications.
1992 */
1993 bzero(&fromsa, sizeof(fromsa));
1994 fromsa.sin6_family = AF_INET6;
1995 fromsa.sin6_len = sizeof(struct sockaddr_in6);
1996 fromsa.sin6_addr = ip6->ip6_src;
1997 if (sa6_recoverscope(&fromsa)) {
1998 m_freem(m);
1999 return (IPPROTO_DONE);
2000 }
2001
2002 INP_INFO_RLOCK(&V_ripcbinfo);
2003 LIST_FOREACH(in6p, &V_ripcb, inp_list) {
2004 if ((in6p->inp_vflag & INP_IPV6) == 0)
2005 continue;
2006 if (in6p->inp_ip_p != IPPROTO_ICMPV6)
2007 continue;
2008 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) &&
2009 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst))
2010 continue;
2011 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) &&
2012 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src))
2013 continue;
2014 INP_RLOCK(in6p);
2015 if (ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type,
2016 in6p->in6p_icmp6filt)) {
2017 INP_RUNLOCK(in6p);
2018 continue;
2019 }
2020 if (last != NULL) {
2021 struct mbuf *n = NULL;
2022
2023 /*
2024 * Recent network drivers tend to allocate a single
2025 * mbuf cluster, rather than to make a couple of
2026 * mbufs without clusters. Also, since the IPv6 code
2027 * path tries to avoid m_pullup(), it is highly
2028 * probable that we still have an mbuf cluster here
2029 * even though the necessary length can be stored in an
2030 * mbuf's internal buffer.
2031 * Meanwhile, the default size of the receive socket
2032 * buffer for raw sockets is not so large. This means
2033 * the possibility of packet loss is relatively higher
2034 * than before. To avoid this scenario, we copy the
2035 * received data to a separate mbuf that does not use
2036 * a cluster, if possible.
2037 * XXX: it is better to copy the data after stripping
2038 * intermediate headers.
2039 */
2040 if ((m->m_flags & M_EXT) && m->m_next == NULL &&
2041 m->m_len <= MHLEN) {
2042 n = m_get(M_NOWAIT, m->m_type);
2043 if (n != NULL) {
2044 if (m_dup_pkthdr(n, m, M_NOWAIT)) {
2045 bcopy(m->m_data, n->m_data,
2046 m->m_len);
2047 n->m_len = m->m_len;
2048 } else {
2049 m_free(n);
2050 n = NULL;
2051 }
2052 }
2053 }
2054 if (n != NULL ||
2055 (n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
2056 if (last->inp_flags & INP_CONTROLOPTS)
2057 ip6_savecontrol(last, n, &opts);
2058 /* strip intermediate headers */
2059 m_adj(n, off);
2060 SOCKBUF_LOCK(&last->inp_socket->so_rcv);
2061 if (sbappendaddr_locked(
2062 &last->inp_socket->so_rcv,
2063 (struct sockaddr *)&fromsa, n, opts)
2064 == 0) {
2065 /* should notify about lost packet */
2066 m_freem(n);
2067 if (opts) {
2068 m_freem(opts);
2069 }
2070 SOCKBUF_UNLOCK(
2071 &last->inp_socket->so_rcv);
2072 } else
2073 sorwakeup_locked(last->inp_socket);
2074 opts = NULL;
2075 }
2076 INP_RUNLOCK(last);
2077 }
2078 last = in6p;
2079 }
2080 INP_INFO_RUNLOCK(&V_ripcbinfo);
2081 if (last != NULL) {
2082 if (last->inp_flags & INP_CONTROLOPTS)
2083 ip6_savecontrol(last, m, &opts);
2084 /* strip intermediate headers */
2085 m_adj(m, off);
2086
2087 /* avoid using mbuf clusters if possible (see above) */
2088 if ((m->m_flags & M_EXT) && m->m_next == NULL &&
2089 m->m_len <= MHLEN) {
2090 struct mbuf *n;
2091
2092 n = m_get(M_NOWAIT, m->m_type);
2093 if (n != NULL) {
2094 if (m_dup_pkthdr(n, m, M_NOWAIT)) {
2095 bcopy(m->m_data, n->m_data, m->m_len);
2096 n->m_len = m->m_len;
2097
2098 m_freem(m);
2099 m = n;
2100 } else {
2101 m_freem(n);
2102 n = NULL;
2103 }
2104 }
2105 }
2106 SOCKBUF_LOCK(&last->inp_socket->so_rcv);
2107 if (sbappendaddr_locked(&last->inp_socket->so_rcv,
2108 (struct sockaddr *)&fromsa, m, opts) == 0) {
2109 m_freem(m);
2110 if (opts)
2111 m_freem(opts);
2112 SOCKBUF_UNLOCK(&last->inp_socket->so_rcv);
2113 } else
2114 sorwakeup_locked(last->inp_socket);
2115 INP_RUNLOCK(last);
2116 } else {
2117 m_freem(m);
2118 IP6STAT_DEC(ip6s_delivered);
2119 }
2120 return IPPROTO_DONE;
2121 }
2122
2123 /*
2124 * Reflect the ip6 packet back to the source.
2125 * OFF points to the icmp6 header, counted from the top of the mbuf.
2126 */
2127 void
2128 icmp6_reflect(struct mbuf *m, size_t off)
2129 {
2130 struct ip6_hdr *ip6;
2131 struct icmp6_hdr *icmp6;
2132 struct in6_ifaddr *ia = NULL;
2133 int plen;
2134 int type, code;
2135 struct ifnet *outif = NULL;
2136 struct in6_addr origdst, src, *srcp = NULL;
2137
2138 /* too short to reflect */
2139 if (off < sizeof(struct ip6_hdr)) {
2140 nd6log((LOG_DEBUG,
2141 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n",
2142 (u_long)off, (u_long)sizeof(struct ip6_hdr),
2143 __FILE__, __LINE__));
2144 goto bad;
2145 }
2146
2147 /*
2148 * If there are extra headers between IPv6 and ICMPv6, strip
2149 * off that header first.
2150 */
2151 #ifdef DIAGNOSTIC
2152 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN)
2153 panic("assumption failed in icmp6_reflect");
2154 #endif
2155 if (off > sizeof(struct ip6_hdr)) {
2156 size_t l;
2157 struct ip6_hdr nip6;
2158
2159 l = off - sizeof(struct ip6_hdr);
2160 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6);
2161 m_adj(m, l);
2162 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
2163 if (m->m_len < l) {
2164 if ((m = m_pullup(m, l)) == NULL)
2165 return;
2166 }
2167 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6));
2168 } else /* off == sizeof(struct ip6_hdr) */ {
2169 size_t l;
2170 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
2171 if (m->m_len < l) {
2172 if ((m = m_pullup(m, l)) == NULL)
2173 return;
2174 }
2175 }
2176 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr);
2177 ip6 = mtod(m, struct ip6_hdr *);
2178 ip6->ip6_nxt = IPPROTO_ICMPV6;
2179 icmp6 = (struct icmp6_hdr *)(ip6 + 1);
2180 type = icmp6->icmp6_type; /* keep type for statistics */
2181 code = icmp6->icmp6_code; /* ditto. */
2182
2183 origdst = ip6->ip6_dst;
2184 /*
2185 * ip6_input() drops a packet if its src is multicast.
2186 * So, the src is never multicast.
2187 */
2188 ip6->ip6_dst = ip6->ip6_src;
2189
2190 /*
2191 * If the incoming packet was addressed directly to us (i.e. unicast),
2192 * use dst as the src for the reply.
2193 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible
2194 * (for example) when we encounter an error while forwarding procedure
2195 * destined to a duplicated address of ours.
2196 * Note that ip6_getdstifaddr() may fail if we are in an error handling
2197 * procedure of an outgoing packet of our own, in which case we need
2198 * to search in the ifaddr list.
2199 */
2200 if (!IN6_IS_ADDR_MULTICAST(&origdst)) {
2201 if ((ia = ip6_getdstifaddr(m))) {
2202 if (!(ia->ia6_flags &
2203 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)))
2204 srcp = &ia->ia_addr.sin6_addr;
2205 } else {
2206 struct sockaddr_in6 d;
2207
2208 bzero(&d, sizeof(d));
2209 d.sin6_family = AF_INET6;
2210 d.sin6_len = sizeof(d);
2211 d.sin6_addr = origdst;
2212 ia = (struct in6_ifaddr *)
2213 ifa_ifwithaddr((struct sockaddr *)&d);
2214 if (ia &&
2215 !(ia->ia6_flags &
2216 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) {
2217 srcp = &ia->ia_addr.sin6_addr;
2218 }
2219 }
2220 }
2221
2222 if (srcp == NULL) {
2223 int e;
2224 struct sockaddr_in6 sin6;
2225 struct route_in6 ro;
2226
2227 /*
2228 * This case matches to multicasts, our anycast, or unicasts
2229 * that we do not own. Select a source address based on the
2230 * source address of the erroneous packet.
2231 */
2232 bzero(&sin6, sizeof(sin6));
2233 sin6.sin6_family = AF_INET6;
2234 sin6.sin6_len = sizeof(sin6);
2235 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */
2236
2237 bzero(&ro, sizeof(ro));
2238 e = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &src);
2239 if (ro.ro_rt)
2240 RTFREE(ro.ro_rt); /* XXX: we could use this */
2241 if (e) {
2242 char ip6buf[INET6_ADDRSTRLEN];
2243 nd6log((LOG_DEBUG,
2244 "icmp6_reflect: source can't be determined: "
2245 "dst=%s, error=%d\n",
2246 ip6_sprintf(ip6buf, &sin6.sin6_addr), e));
2247 goto bad;
2248 }
2249 srcp = &src;
2250 }
2251
2252 ip6->ip6_src = *srcp;
2253 ip6->ip6_flow = 0;
2254 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
2255 ip6->ip6_vfc |= IPV6_VERSION;
2256 ip6->ip6_nxt = IPPROTO_ICMPV6;
2257 if (outif)
2258 ip6->ip6_hlim = ND_IFINFO(outif)->chlim;
2259 else if (m->m_pkthdr.rcvif) {
2260 /* XXX: This may not be the outgoing interface */
2261 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim;
2262 } else
2263 ip6->ip6_hlim = V_ip6_defhlim;
2264
2265 icmp6->icmp6_cksum = 0;
2266 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6,
2267 sizeof(struct ip6_hdr), plen);
2268
2269 /*
2270 * XXX option handling
2271 */
2272
2273 m->m_flags &= ~(M_BCAST|M_MCAST);
2274
2275 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
2276 if (outif)
2277 icmp6_ifoutstat_inc(outif, type, code);
2278
2279 if (ia != NULL)
2280 ifa_free(&ia->ia_ifa);
2281 return;
2282
2283 bad:
2284 if (ia != NULL)
2285 ifa_free(&ia->ia_ifa);
2286 m_freem(m);
2287 return;
2288 }
2289
2290 void
2291 icmp6_fasttimo(void)
2292 {
2293
2294 mld_fasttimo();
2295 }
2296
2297 void
2298 icmp6_slowtimo(void)
2299 {
2300
2301 mld_slowtimo();
2302 }
2303
2304 static const char *
2305 icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6,
2306 struct in6_addr *tgt6)
2307 {
2308 static char buf[1024];
2309 char ip6bufs[INET6_ADDRSTRLEN];
2310 char ip6bufd[INET6_ADDRSTRLEN];
2311 char ip6buft[INET6_ADDRSTRLEN];
2312 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)",
2313 ip6_sprintf(ip6bufs, src6), ip6_sprintf(ip6bufd, dst6),
2314 ip6_sprintf(ip6buft, tgt6));
2315 return buf;
2316 }
2317
2318 void
2319 icmp6_redirect_input(struct mbuf *m, int off)
2320 {
2321 struct ifnet *ifp;
2322 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
2323 struct nd_redirect *nd_rd;
2324 int icmp6len = ntohs(ip6->ip6_plen);
2325 char *lladdr = NULL;
2326 int lladdrlen = 0;
2327 struct rtentry *rt = NULL;
2328 int is_router;
2329 int is_onlink;
2330 struct in6_addr src6 = ip6->ip6_src;
2331 struct in6_addr redtgt6;
2332 struct in6_addr reddst6;
2333 union nd_opts ndopts;
2334 char ip6buf[INET6_ADDRSTRLEN];
2335
2336 M_ASSERTPKTHDR(m);
2337 KASSERT(m->m_pkthdr.rcvif != NULL, ("%s: no rcvif", __func__));
2338
2339 ifp = m->m_pkthdr.rcvif;
2340
2341 /* XXX if we are router, we don't update route by icmp6 redirect */
2342 if (V_ip6_forwarding)
2343 goto freeit;
2344 if (!V_icmp6_rediraccept)
2345 goto freeit;
2346
2347 #ifndef PULLDOWN_TEST
2348 IP6_EXTHDR_CHECK(m, off, icmp6len,);
2349 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off);
2350 #else
2351 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len);
2352 if (nd_rd == NULL) {
2353 ICMP6STAT_INC(icp6s_tooshort);
2354 return;
2355 }
2356 #endif
2357 redtgt6 = nd_rd->nd_rd_target;
2358 reddst6 = nd_rd->nd_rd_dst;
2359
2360 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) ||
2361 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) {
2362 goto freeit;
2363 }
2364
2365 /* validation */
2366 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) {
2367 nd6log((LOG_ERR,
2368 "ICMP6 redirect sent from %s rejected; "
2369 "must be from linklocal\n",
2370 ip6_sprintf(ip6buf, &src6)));
2371 goto bad;
2372 }
2373 if (ip6->ip6_hlim != 255) {
2374 nd6log((LOG_ERR,
2375 "ICMP6 redirect sent from %s rejected; "
2376 "hlim=%d (must be 255)\n",
2377 ip6_sprintf(ip6buf, &src6), ip6->ip6_hlim));
2378 goto bad;
2379 }
2380 {
2381 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */
2382 struct sockaddr_in6 sin6;
2383 struct in6_addr *gw6;
2384
2385 bzero(&sin6, sizeof(sin6));
2386 sin6.sin6_family = AF_INET6;
2387 sin6.sin6_len = sizeof(struct sockaddr_in6);
2388 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6));
2389 rt = in6_rtalloc1((struct sockaddr *)&sin6, 0, 0UL, RT_DEFAULT_FIB);
2390 if (rt) {
2391 if (rt->rt_gateway == NULL ||
2392 rt->rt_gateway->sa_family != AF_INET6) {
2393 RTFREE_LOCKED(rt);
2394 nd6log((LOG_ERR,
2395 "ICMP6 redirect rejected; no route "
2396 "with inet6 gateway found for redirect dst: %s\n",
2397 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2398 goto bad;
2399 }
2400
2401 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr);
2402 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) {
2403 RTFREE_LOCKED(rt);
2404 nd6log((LOG_ERR,
2405 "ICMP6 redirect rejected; "
2406 "not equal to gw-for-src=%s (must be same): "
2407 "%s\n",
2408 ip6_sprintf(ip6buf, gw6),
2409 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2410 goto bad;
2411 }
2412 } else {
2413 nd6log((LOG_ERR,
2414 "ICMP6 redirect rejected; "
2415 "no route found for redirect dst: %s\n",
2416 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2417 goto bad;
2418 }
2419 RTFREE_LOCKED(rt);
2420 rt = NULL;
2421 }
2422 if (IN6_IS_ADDR_MULTICAST(&reddst6)) {
2423 nd6log((LOG_ERR,
2424 "ICMP6 redirect rejected; "
2425 "redirect dst must be unicast: %s\n",
2426 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2427 goto bad;
2428 }
2429
2430 is_router = is_onlink = 0;
2431 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
2432 is_router = 1; /* router case */
2433 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0)
2434 is_onlink = 1; /* on-link destination case */
2435 if (!is_router && !is_onlink) {
2436 nd6log((LOG_ERR,
2437 "ICMP6 redirect rejected; "
2438 "neither router case nor onlink case: %s\n",
2439 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2440 goto bad;
2441 }
2442 /* validation passed */
2443
2444 icmp6len -= sizeof(*nd_rd);
2445 nd6_option_init(nd_rd + 1, icmp6len, &ndopts);
2446 if (nd6_options(&ndopts) < 0) {
2447 nd6log((LOG_INFO, "%s: invalid ND option, rejected: %s\n",
2448 __func__, icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2449 /* nd6_options have incremented stats */
2450 goto freeit;
2451 }
2452
2453 if (ndopts.nd_opts_tgt_lladdr) {
2454 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
2455 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
2456 }
2457
2458 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
2459 nd6log((LOG_INFO, "%s: lladdrlen mismatch for %s "
2460 "(if %d, icmp6 packet %d): %s\n",
2461 __func__, ip6_sprintf(ip6buf, &redtgt6),
2462 ifp->if_addrlen, lladdrlen - 2,
2463 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2464 goto bad;
2465 }
2466
2467 /* RFC 2461 8.3 */
2468 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT,
2469 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER);
2470
2471 if (!is_onlink) { /* better router case. perform rtredirect. */
2472 /* perform rtredirect */
2473 struct sockaddr_in6 sdst;
2474 struct sockaddr_in6 sgw;
2475 struct sockaddr_in6 ssrc;
2476 u_int fibnum;
2477
2478 bzero(&sdst, sizeof(sdst));
2479 bzero(&sgw, sizeof(sgw));
2480 bzero(&ssrc, sizeof(ssrc));
2481 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6;
2482 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len =
2483 sizeof(struct sockaddr_in6);
2484 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr));
2485 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
2486 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr));
2487 for (fibnum = 0; fibnum < rt_numfibs; fibnum++)
2488 in6_rtredirect((struct sockaddr *)&sdst,
2489 (struct sockaddr *)&sgw, (struct sockaddr *)NULL,
2490 RTF_GATEWAY | RTF_HOST, (struct sockaddr *)&ssrc,
2491 fibnum);
2492 }
2493 /* finally update cached route in each socket via pfctlinput */
2494 {
2495 struct sockaddr_in6 sdst;
2496
2497 bzero(&sdst, sizeof(sdst));
2498 sdst.sin6_family = AF_INET6;
2499 sdst.sin6_len = sizeof(struct sockaddr_in6);
2500 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
2501 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst);
2502 }
2503
2504 freeit:
2505 m_freem(m);
2506 return;
2507
2508 bad:
2509 ICMP6STAT_INC(icp6s_badredirect);
2510 m_freem(m);
2511 }
2512
2513 void
2514 icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt)
2515 {
2516 struct ifnet *ifp; /* my outgoing interface */
2517 struct in6_addr *ifp_ll6;
2518 struct in6_addr *router_ll6;
2519 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */
2520 struct mbuf *m = NULL; /* newly allocated one */
2521 struct m_tag *mtag;
2522 struct ip6_hdr *ip6; /* m as struct ip6_hdr */
2523 struct nd_redirect *nd_rd;
2524 struct llentry *ln = NULL;
2525 size_t maxlen;
2526 u_char *p;
2527 struct ifnet *outif = NULL;
2528 struct sockaddr_in6 src_sa;
2529
2530 icmp6_errcount(ND_REDIRECT, 0);
2531
2532 /* if we are not router, we don't send icmp6 redirect */
2533 if (!V_ip6_forwarding)
2534 goto fail;
2535
2536 /* sanity check */
2537 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp))
2538 goto fail;
2539
2540 /*
2541 * Address check:
2542 * the source address must identify a neighbor, and
2543 * the destination address must not be a multicast address
2544 * [RFC 2461, sec 8.2]
2545 */
2546 sip6 = mtod(m0, struct ip6_hdr *);
2547 bzero(&src_sa, sizeof(src_sa));
2548 src_sa.sin6_family = AF_INET6;
2549 src_sa.sin6_len = sizeof(src_sa);
2550 src_sa.sin6_addr = sip6->ip6_src;
2551 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0)
2552 goto fail;
2553 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst))
2554 goto fail; /* what should we do here? */
2555
2556 /* rate limit */
2557 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0))
2558 goto fail;
2559
2560 /*
2561 * Since we are going to append up to 1280 bytes (= IPV6_MMTU),
2562 * we almost always ask for an mbuf cluster for simplicity.
2563 * (MHLEN < IPV6_MMTU is almost always true)
2564 */
2565 #if IPV6_MMTU >= MCLBYTES
2566 # error assumption failed about IPV6_MMTU and MCLBYTES
2567 #endif
2568 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
2569 if (m == NULL)
2570 goto fail;
2571 M_SETFIB(m, rt->rt_fibnum);
2572 maxlen = M_TRAILINGSPACE(m);
2573 maxlen = min(IPV6_MMTU, maxlen);
2574 /* just for safety */
2575 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) +
2576 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) {
2577 goto fail;
2578 }
2579
2580 {
2581 /* get ip6 linklocal address for ifp(my outgoing interface). */
2582 struct in6_ifaddr *ia;
2583 if ((ia = in6ifa_ifpforlinklocal(ifp,
2584 IN6_IFF_NOTREADY|
2585 IN6_IFF_ANYCAST)) == NULL)
2586 goto fail;
2587 ifp_ll6 = &ia->ia_addr.sin6_addr;
2588 /* XXXRW: reference released prematurely. */
2589 ifa_free(&ia->ia_ifa);
2590 }
2591
2592 /* get ip6 linklocal address for the router. */
2593 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) {
2594 struct sockaddr_in6 *sin6;
2595 sin6 = (struct sockaddr_in6 *)rt->rt_gateway;
2596 router_ll6 = &sin6->sin6_addr;
2597 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6))
2598 router_ll6 = (struct in6_addr *)NULL;
2599 } else
2600 router_ll6 = (struct in6_addr *)NULL;
2601
2602 /* ip6 */
2603 ip6 = mtod(m, struct ip6_hdr *);
2604 ip6->ip6_flow = 0;
2605 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
2606 ip6->ip6_vfc |= IPV6_VERSION;
2607 /* ip6->ip6_plen will be set later */
2608 ip6->ip6_nxt = IPPROTO_ICMPV6;
2609 ip6->ip6_hlim = 255;
2610 /* ip6->ip6_src must be linklocal addr for my outgoing if. */
2611 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr));
2612 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr));
2613
2614 /* ND Redirect */
2615 nd_rd = (struct nd_redirect *)(ip6 + 1);
2616 nd_rd->nd_rd_type = ND_REDIRECT;
2617 nd_rd->nd_rd_code = 0;
2618 nd_rd->nd_rd_reserved = 0;
2619 if (rt->rt_flags & RTF_GATEWAY) {
2620 /*
2621 * nd_rd->nd_rd_target must be a link-local address in
2622 * better router cases.
2623 */
2624 if (!router_ll6)
2625 goto fail;
2626 bcopy(router_ll6, &nd_rd->nd_rd_target,
2627 sizeof(nd_rd->nd_rd_target));
2628 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2629 sizeof(nd_rd->nd_rd_dst));
2630 } else {
2631 /* make sure redtgt == reddst */
2632 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target,
2633 sizeof(nd_rd->nd_rd_target));
2634 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2635 sizeof(nd_rd->nd_rd_dst));
2636 }
2637
2638 p = (u_char *)(nd_rd + 1);
2639
2640 if (!router_ll6)
2641 goto nolladdropt;
2642
2643 {
2644 /* target lladdr option */
2645 int len;
2646 struct nd_opt_hdr *nd_opt;
2647 char *lladdr;
2648
2649 IF_AFDATA_RLOCK(ifp);
2650 ln = nd6_lookup(router_ll6, 0, ifp);
2651 IF_AFDATA_RUNLOCK(ifp);
2652 if (ln == NULL)
2653 goto nolladdropt;
2654
2655 len = sizeof(*nd_opt) + ifp->if_addrlen;
2656 len = (len + 7) & ~7; /* round by 8 */
2657 /* safety check */
2658 if (len + (p - (u_char *)ip6) > maxlen)
2659 goto nolladdropt;
2660
2661 if (ln->la_flags & LLE_VALID) {
2662 nd_opt = (struct nd_opt_hdr *)p;
2663 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
2664 nd_opt->nd_opt_len = len >> 3;
2665 lladdr = (char *)(nd_opt + 1);
2666 bcopy(&ln->ll_addr, lladdr, ifp->if_addrlen);
2667 p += len;
2668 }
2669 }
2670 nolladdropt:
2671 if (ln != NULL)
2672 LLE_RUNLOCK(ln);
2673
2674 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2675
2676 /* just to be safe */
2677 #ifdef M_DECRYPTED /*not openbsd*/
2678 if (m0->m_flags & M_DECRYPTED)
2679 goto noredhdropt;
2680 #endif
2681 if (p - (u_char *)ip6 > maxlen)
2682 goto noredhdropt;
2683
2684 {
2685 /* redirected header option */
2686 int len;
2687 struct nd_opt_rd_hdr *nd_opt_rh;
2688
2689 /*
2690 * compute the maximum size for icmp6 redirect header option.
2691 * XXX room for auth header?
2692 */
2693 len = maxlen - (p - (u_char *)ip6);
2694 len &= ~7;
2695
2696 /* This is just for simplicity. */
2697 if (m0->m_pkthdr.len != m0->m_len) {
2698 if (m0->m_next) {
2699 m_freem(m0->m_next);
2700 m0->m_next = NULL;
2701 }
2702 m0->m_pkthdr.len = m0->m_len;
2703 }
2704
2705 /*
2706 * Redirected header option spec (RFC2461 4.6.3) talks nothing
2707 * about padding/truncate rule for the original IP packet.
2708 * From the discussion on IPv6imp in Feb 1999,
2709 * the consensus was:
2710 * - "attach as much as possible" is the goal
2711 * - pad if not aligned (original size can be guessed by
2712 * original ip6 header)
2713 * Following code adds the padding if it is simple enough,
2714 * and truncates if not.
2715 */
2716 if (m0->m_next || m0->m_pkthdr.len != m0->m_len)
2717 panic("assumption failed in %s:%d", __FILE__,
2718 __LINE__);
2719
2720 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) {
2721 /* not enough room, truncate */
2722 m0->m_pkthdr.len = m0->m_len = len -
2723 sizeof(*nd_opt_rh);
2724 } else {
2725 /* enough room, pad or truncate */
2726 size_t extra;
2727
2728 extra = m0->m_pkthdr.len % 8;
2729 if (extra) {
2730 /* pad if easy enough, truncate if not */
2731 if (8 - extra <= M_TRAILINGSPACE(m0)) {
2732 /* pad */
2733 m0->m_len += (8 - extra);
2734 m0->m_pkthdr.len += (8 - extra);
2735 } else {
2736 /* truncate */
2737 m0->m_pkthdr.len -= extra;
2738 m0->m_len -= extra;
2739 }
2740 }
2741 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh);
2742 m0->m_pkthdr.len = m0->m_len = len -
2743 sizeof(*nd_opt_rh);
2744 }
2745
2746 nd_opt_rh = (struct nd_opt_rd_hdr *)p;
2747 bzero(nd_opt_rh, sizeof(*nd_opt_rh));
2748 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER;
2749 nd_opt_rh->nd_opt_rh_len = len >> 3;
2750 p += sizeof(*nd_opt_rh);
2751 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2752
2753 /* connect m0 to m */
2754 m_tag_delete_chain(m0, NULL);
2755 m0->m_flags &= ~M_PKTHDR;
2756 m->m_next = m0;
2757 m->m_pkthdr.len = m->m_len + m0->m_len;
2758 m0 = NULL;
2759 }
2760 noredhdropt:;
2761 if (m0) {
2762 m_freem(m0);
2763 m0 = NULL;
2764 }
2765
2766 /* XXX: clear embedded link IDs in the inner header */
2767 in6_clearscope(&sip6->ip6_src);
2768 in6_clearscope(&sip6->ip6_dst);
2769 in6_clearscope(&nd_rd->nd_rd_target);
2770 in6_clearscope(&nd_rd->nd_rd_dst);
2771
2772 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
2773
2774 nd_rd->nd_rd_cksum = 0;
2775 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6,
2776 sizeof(*ip6), ntohs(ip6->ip6_plen));
2777
2778 if (send_sendso_input_hook != NULL) {
2779 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, sizeof(unsigned short),
2780 M_NOWAIT);
2781 if (mtag == NULL)
2782 goto fail;
2783 *(unsigned short *)(mtag + 1) = nd_rd->nd_rd_type;
2784 m_tag_prepend(m, mtag);
2785 }
2786
2787 /* send the packet to outside... */
2788 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
2789 if (outif) {
2790 icmp6_ifstat_inc(outif, ifs6_out_msg);
2791 icmp6_ifstat_inc(outif, ifs6_out_redirect);
2792 }
2793 ICMP6STAT_INC(icp6s_outhist[ND_REDIRECT]);
2794
2795 return;
2796
2797 fail:
2798 if (m)
2799 m_freem(m);
2800 if (m0)
2801 m_freem(m0);
2802 }
2803
2804 /*
2805 * ICMPv6 socket option processing.
2806 */
2807 int
2808 icmp6_ctloutput(struct socket *so, struct sockopt *sopt)
2809 {
2810 int error = 0;
2811 int optlen;
2812 struct inpcb *inp = sotoinpcb(so);
2813 int level, op, optname;
2814
2815 if (sopt) {
2816 level = sopt->sopt_level;
2817 op = sopt->sopt_dir;
2818 optname = sopt->sopt_name;
2819 optlen = sopt->sopt_valsize;
2820 } else
2821 level = op = optname = optlen = 0;
2822
2823 if (level != IPPROTO_ICMPV6) {
2824 return EINVAL;
2825 }
2826
2827 switch (op) {
2828 case PRCO_SETOPT:
2829 switch (optname) {
2830 case ICMP6_FILTER:
2831 {
2832 struct icmp6_filter ic6f;
2833
2834 if (optlen != sizeof(ic6f)) {
2835 error = EMSGSIZE;
2836 break;
2837 }
2838 error = sooptcopyin(sopt, &ic6f, optlen, optlen);
2839 if (error == 0) {
2840 INP_WLOCK(inp);
2841 *inp->in6p_icmp6filt = ic6f;
2842 INP_WUNLOCK(inp);
2843 }
2844 break;
2845 }
2846
2847 default:
2848 error = ENOPROTOOPT;
2849 break;
2850 }
2851 break;
2852
2853 case PRCO_GETOPT:
2854 switch (optname) {
2855 case ICMP6_FILTER:
2856 {
2857 struct icmp6_filter ic6f;
2858
2859 INP_RLOCK(inp);
2860 ic6f = *inp->in6p_icmp6filt;
2861 INP_RUNLOCK(inp);
2862 error = sooptcopyout(sopt, &ic6f, sizeof(ic6f));
2863 break;
2864 }
2865
2866 default:
2867 error = ENOPROTOOPT;
2868 break;
2869 }
2870 break;
2871 }
2872
2873 return (error);
2874 }
2875
2876 /*
2877 * Perform rate limit check.
2878 * Returns 0 if it is okay to send the icmp6 packet.
2879 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate
2880 * limitation.
2881 *
2882 * XXX per-destination/type check necessary?
2883 *
2884 * dst - not used at this moment
2885 * type - not used at this moment
2886 * code - not used at this moment
2887 */
2888 static int
2889 icmp6_ratelimit(const struct in6_addr *dst, const int type,
2890 const int code)
2891 {
2892 int ret;
2893
2894 ret = 0; /* okay to send */
2895
2896 /* PPS limit */
2897 if (!ppsratecheck(&V_icmp6errppslim_last, &V_icmp6errpps_count,
2898 V_icmp6errppslim)) {
2899 /* The packet is subject to rate limit */
2900 ret++;
2901 }
2902
2903 return ret;
2904 }
Cache object: 04bb0f5eee5eab001cd98d337aa11d35
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