FreeBSD kernel IPv6 code
icmp6.c
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1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the project nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * $KAME: icmp6.c,v 1.211 2001/04/04 05:56:20 itojun Exp $
32 */
33
34/*-
35 * Copyright (c) 1982, 1986, 1988, 1993
36 * The Regents of the University of California. All rights reserved.
37 *
38 * Redistribution and use in source and binary forms, with or without
39 * modification, are permitted provided that the following conditions
40 * are met:
41 * 1. Redistributions of source code must retain the above copyright
42 * notice, this list of conditions and the following disclaimer.
43 * 2. Redistributions in binary form must reproduce the above copyright
44 * notice, this list of conditions and the following disclaimer in the
45 * documentation and/or other materials provided with the distribution.
46 * 3. Neither the name of the University nor the names of its contributors
47 * may be used to endorse or promote products derived from this software
48 * without specific prior written permission.
49 *
50 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
51 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
52 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
53 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
54 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
55 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
56 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
57 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
58 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
59 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
60 * SUCH DAMAGE.
61 *
62 * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94
63 */
64
65#include <sys/cdefs.h>
66__FBSDID("$FreeBSD$");
67
68#define MBUF_PRIVATE /* XXXRW: Optimisation tries to avoid M_EXT mbufs */
69
70#include "opt_inet.h"
71#include "opt_inet6.h"
72
73#include <sys/param.h>
74#include <sys/domain.h>
75#include <sys/jail.h>
76#include <sys/kernel.h>
77#include <sys/lock.h>
78#include <sys/malloc.h>
79#include <sys/mbuf.h>
80#include <sys/proc.h>
81#include <sys/protosw.h>
82#include <sys/signalvar.h>
83#include <sys/socket.h>
84#include <sys/socketvar.h>
85#include <sys/sx.h>
86#include <sys/syslog.h>
87#include <sys/systm.h>
88#include <sys/time.h>
89
90#include <net/if.h>
91#include <net/if_var.h>
92#include <net/if_dl.h>
93#include <net/if_llatbl.h>
94#include <net/if_types.h>
95#include <net/route.h>
96#include <net/route/route_ctl.h>
97#include <net/route/nhop.h>
98#include <net/vnet.h>
99
100#include <netinet/in.h>
101#include <netinet/in_pcb.h>
102#include <netinet/in_var.h>
103#include <netinet/ip6.h>
104#include <netinet/icmp6.h>
105#include <netinet/tcp_var.h>
106
107#include <netinet6/in6_fib.h>
108#include <netinet6/in6_ifattach.h>
109#include <netinet6/in6_pcb.h>
110#include <netinet6/ip6protosw.h>
111#include <netinet6/ip6_var.h>
112#include <netinet6/scope6_var.h>
113#include <netinet6/mld6_var.h>
114#include <netinet6/nd6.h>
115#include <netinet6/send.h>
116
117extern struct domain inet6domain;
118
119VNET_PCPUSTAT_DEFINE(struct icmp6stat, icmp6stat);
120VNET_PCPUSTAT_SYSINIT(icmp6stat);
121
122#ifdef VIMAGE
123VNET_PCPUSTAT_SYSUNINIT(icmp6stat);
124#endif /* VIMAGE */
125
126VNET_DECLARE(struct inpcbinfo, ripcbinfo);
127VNET_DECLARE(int, icmp6errppslim);
128VNET_DEFINE_STATIC(int, icmp6errpps_count) = 0;
129VNET_DEFINE_STATIC(struct timeval, icmp6errppslim_last);
130VNET_DECLARE(int, icmp6_nodeinfo);
131
132#define V_ripcbinfo VNET(ripcbinfo)
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
138static void icmp6_errcount(int, int);
139static int icmp6_rip6_input(struct mbuf **, int);
140static void icmp6_reflect(struct mbuf *, size_t);
141static int icmp6_ratelimit(const struct in6_addr *, const int, const int);
142static const char *icmp6_redirect_diag(struct in6_addr *,
143 struct in6_addr *, struct in6_addr *);
144static struct mbuf *ni6_input(struct mbuf *, int, struct prison *);
145static struct mbuf *ni6_nametodns(const char *, int, int);
146static int ni6_dnsmatch(const char *, int, const char *, int);
147static int ni6_addrs(struct icmp6_nodeinfo *, struct mbuf *,
148 struct ifnet **, struct in6_addr *);
149static int ni6_store_addrs(struct icmp6_nodeinfo *, struct icmp6_nodeinfo *,
150 struct ifnet *, int);
151static int icmp6_notify_error(struct mbuf **, int, int, int);
152
153/*
154 * Kernel module interface for updating icmp6stat. The argument is an index
155 * into icmp6stat treated as an array of u_quad_t. While this encodes the
156 * general layout of icmp6stat into the caller, it doesn't encode its
157 * location, so that future changes to add, for example, per-CPU stats
158 * support won't cause binary compatibility problems for kernel modules.
159 */
160void
161kmod_icmp6stat_inc(int statnum)
162{
163
164 counter_u64_add(VNET(icmp6stat)[statnum], 1);
165}
166
167static void
168icmp6_errcount(int type, int code)
169{
170 switch (type) {
171 case ICMP6_DST_UNREACH:
172 switch (code) {
173 case ICMP6_DST_UNREACH_NOROUTE:
174 ICMP6STAT_INC(icp6s_odst_unreach_noroute);
175 return;
176 case ICMP6_DST_UNREACH_ADMIN:
177 ICMP6STAT_INC(icp6s_odst_unreach_admin);
178 return;
179 case ICMP6_DST_UNREACH_BEYONDSCOPE:
180 ICMP6STAT_INC(icp6s_odst_unreach_beyondscope);
181 return;
182 case ICMP6_DST_UNREACH_ADDR:
183 ICMP6STAT_INC(icp6s_odst_unreach_addr);
184 return;
185 case ICMP6_DST_UNREACH_NOPORT:
186 ICMP6STAT_INC(icp6s_odst_unreach_noport);
187 return;
188 }
189 break;
190 case ICMP6_PACKET_TOO_BIG:
191 ICMP6STAT_INC(icp6s_opacket_too_big);
192 return;
193 case ICMP6_TIME_EXCEEDED:
194 switch (code) {
195 case ICMP6_TIME_EXCEED_TRANSIT:
196 ICMP6STAT_INC(icp6s_otime_exceed_transit);
197 return;
198 case ICMP6_TIME_EXCEED_REASSEMBLY:
199 ICMP6STAT_INC(icp6s_otime_exceed_reassembly);
200 return;
201 }
202 break;
203 case ICMP6_PARAM_PROB:
204 switch (code) {
205 case ICMP6_PARAMPROB_HEADER:
206 ICMP6STAT_INC(icp6s_oparamprob_header);
207 return;
208 case ICMP6_PARAMPROB_NEXTHEADER:
209 ICMP6STAT_INC(icp6s_oparamprob_nextheader);
210 return;
211 case ICMP6_PARAMPROB_OPTION:
212 ICMP6STAT_INC(icp6s_oparamprob_option);
213 return;
214 }
215 break;
216 case ND_REDIRECT:
217 ICMP6STAT_INC(icp6s_oredirect);
218 return;
219 }
220 ICMP6STAT_INC(icp6s_ounknown);
221}
222
223/*
224 * A wrapper function for icmp6_error() necessary when the erroneous packet
225 * may not contain enough scope zone information.
226 */
227void
228icmp6_error2(struct mbuf *m, int type, int code, int param,
229 struct ifnet *ifp)
230{
231 struct ip6_hdr *ip6;
232
233 if (ifp == NULL)
234 return;
235
236 if (m->m_len < sizeof(struct ip6_hdr)) {
237 m = m_pullup(m, sizeof(struct ip6_hdr));
238 if (m == NULL) {
239 IP6STAT_INC(ip6s_exthdrtoolong);
240 return;
241 }
242 }
243 ip6 = mtod(m, struct ip6_hdr *);
244
245 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0)
246 return;
247 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0)
248 return;
249
250 icmp6_error(m, type, code, param);
251}
252
253/*
254 * Generate an error packet of type error in response to bad IP6 packet.
255 */
256void
257icmp6_error(struct mbuf *m, int type, int code, int param)
258{
259 struct ip6_hdr *oip6, *nip6;
260 struct icmp6_hdr *icmp6;
261 struct epoch_tracker et;
262 u_int preplen;
263 int off;
264 int nxt;
265
266 ICMP6STAT_INC(icp6s_error);
267
268 /* count per-type-code statistics */
269 icmp6_errcount(type, code);
270
271#ifdef M_DECRYPTED /*not openbsd*/
272 if (m->m_flags & M_DECRYPTED) {
273 ICMP6STAT_INC(icp6s_canterror);
274 goto freeit;
275 }
276#endif
277
278 if (m->m_len < sizeof(struct ip6_hdr)) {
279 m = m_pullup(m, sizeof(struct ip6_hdr));
280 if (m == NULL) {
281 IP6STAT_INC(ip6s_exthdrtoolong);
282 return;
283 }
284 }
285 oip6 = mtod(m, struct ip6_hdr *);
286
287 /*
288 * If the destination address of the erroneous packet is a multicast
289 * address, or the packet was sent using link-layer multicast,
290 * we should basically suppress sending an error (RFC 2463, Section
291 * 2.4).
292 * We have two exceptions (the item e.2 in that section):
293 * - the Packet Too Big message can be sent for path MTU discovery.
294 * - the Parameter Problem Message that can be allowed an icmp6 error
295 * in the option type field. This check has been done in
296 * ip6_unknown_opt(), so we can just check the type and code.
297 */
298 if ((m->m_flags & (M_BCAST|M_MCAST) ||
299 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) &&
300 (type != ICMP6_PACKET_TOO_BIG &&
301 (type != ICMP6_PARAM_PROB ||
302 code != ICMP6_PARAMPROB_OPTION)))
303 goto freeit;
304
305 /*
306 * RFC 2463, 2.4 (e.5): source address check.
307 * XXX: the case of anycast source?
308 */
309 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) ||
310 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src))
311 goto freeit;
312
313 /*
314 * If we are about to send ICMPv6 against ICMPv6 error/redirect,
315 * don't do it.
316 */
317 nxt = -1;
318 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
319 if (off >= 0 && nxt == IPPROTO_ICMPV6) {
320 struct icmp6_hdr *icp;
321
322 if (m->m_len < off + sizeof(struct icmp6_hdr)) {
323 m = m_pullup(m, off + sizeof(struct icmp6_hdr));
324 if (m == NULL) {
325 IP6STAT_INC(ip6s_exthdrtoolong);
326 return;
327 }
328 }
329 oip6 = mtod(m, struct ip6_hdr *);
330 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
331
332 if (icp->icmp6_type < ICMP6_ECHO_REQUEST ||
333 icp->icmp6_type == ND_REDIRECT) {
334 /*
335 * ICMPv6 error
336 * Special case: for redirect (which is
337 * informational) we must not send icmp6 error.
338 */
339 ICMP6STAT_INC(icp6s_canterror);
340 goto freeit;
341 } else {
342 /* ICMPv6 informational - send the error */
343 }
344 } else {
345 /* non-ICMPv6 - send the error */
346 }
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 ICMP6STAT_INC(icp6s_outhist[type]);
381 NET_EPOCH_ENTER(et);
382 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */
383 NET_EPOCH_EXIT(et);
384
385 return;
386
387 freeit:
388 /*
389 * If we can't tell whether or not we can generate ICMP6, free it.
390 */
391 m_freem(m);
392}
393
394/*
395 * Process a received ICMP6 message.
396 */
397int
398icmp6_input(struct mbuf **mp, int *offp, int proto)
399{
400 struct mbuf *m, *n;
401 struct ifnet *ifp;
402 struct ip6_hdr *ip6, *nip6;
403 struct icmp6_hdr *icmp6, *nicmp6;
404 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
405 int code, error, icmp6len, ip6len, noff, off, sum;
406
407 NET_EPOCH_ASSERT();
408
409 m = *mp;
410 off = *offp;
411
412 if (m->m_len < off + sizeof(struct icmp6_hdr)) {
413 m = m_pullup(m, off + sizeof(struct icmp6_hdr));
414 if (m == NULL) {
415 IP6STAT_INC(ip6s_exthdrtoolong);
416 *mp = m;
417 return (IPPROTO_DONE);
418 }
419 }
420
421 /*
422 * Locate icmp6 structure in mbuf, and check
423 * that not corrupted and of at least minimum length
424 */
425
426 icmp6len = m->m_pkthdr.len - off;
427 if (icmp6len < sizeof(struct icmp6_hdr)) {
428 ICMP6STAT_INC(icp6s_tooshort);
429 goto freeit;
430 }
431
432 ip6 = mtod(m, struct ip6_hdr *);
433 ifp = m->m_pkthdr.rcvif;
434 /*
435 * Check multicast group membership.
436 * Note: SSM filters are not applied for ICMPv6 traffic.
437 */
438 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
439 struct in6_multi *inm;
440
441 inm = in6m_lookup(ifp, &ip6->ip6_dst);
442 if (inm == NULL) {
443 IP6STAT_INC(ip6s_notmember);
444 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
445 goto freeit;
446 }
447 }
448
449 /* Calculate the checksum. */
450 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
451 code = icmp6->icmp6_code;
452 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) {
453 nd6log((LOG_ERR,
454 "ICMP6 checksum error(%d|%x) %s\n",
455 icmp6->icmp6_type, sum,
456 ip6_sprintf(ip6bufs, &ip6->ip6_src)));
457 ICMP6STAT_INC(icp6s_checksum);
458 goto freeit;
459 }
460
461 ICMP6STAT_INC(icp6s_inhist[icmp6->icmp6_type]);
462 icmp6_ifstat_inc(ifp, ifs6_in_msg);
463 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK)
464 icmp6_ifstat_inc(ifp, ifs6_in_error);
465
466 ip6len = sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen);
467 switch (icmp6->icmp6_type) {
468 case ICMP6_DST_UNREACH:
469 icmp6_ifstat_inc(ifp, ifs6_in_dstunreach);
470 switch (code) {
471 case ICMP6_DST_UNREACH_NOROUTE:
472 case ICMP6_DST_UNREACH_ADDR: /* PRC_HOSTDEAD is a DOS */
473 code = PRC_UNREACH_NET;
474 break;
475 case ICMP6_DST_UNREACH_ADMIN:
476 icmp6_ifstat_inc(ifp, ifs6_in_adminprohib);
477 code = PRC_UNREACH_ADMIN_PROHIB;
478 break;
479 case ICMP6_DST_UNREACH_BEYONDSCOPE:
480 /* I mean "source address was incorrect." */
481 code = PRC_PARAMPROB;
482 break;
483 case ICMP6_DST_UNREACH_NOPORT:
484 code = PRC_UNREACH_PORT;
485 break;
486 default:
487 goto badcode;
488 }
489 goto deliver;
490 break;
491
492 case ICMP6_PACKET_TOO_BIG:
493 icmp6_ifstat_inc(ifp, ifs6_in_pkttoobig);
494
495 /* validation is made in icmp6_mtudisc_update */
496
497 code = PRC_MSGSIZE;
498
499 /*
500 * Updating the path MTU will be done after examining
501 * intermediate extension headers.
502 */
503 goto deliver;
504 break;
505
506 case ICMP6_TIME_EXCEEDED:
507 icmp6_ifstat_inc(ifp, ifs6_in_timeexceed);
508 switch (code) {
509 case ICMP6_TIME_EXCEED_TRANSIT:
510 code = PRC_TIMXCEED_INTRANS;
511 break;
512 case ICMP6_TIME_EXCEED_REASSEMBLY:
513 code = PRC_TIMXCEED_REASS;
514 break;
515 default:
516 goto badcode;
517 }
518 goto deliver;
519 break;
520
521 case ICMP6_PARAM_PROB:
522 icmp6_ifstat_inc(ifp, ifs6_in_paramprob);
523 switch (code) {
524 case ICMP6_PARAMPROB_NEXTHEADER:
525 code = PRC_UNREACH_PROTOCOL;
526 break;
527 case ICMP6_PARAMPROB_HEADER:
528 case ICMP6_PARAMPROB_OPTION:
529 code = PRC_PARAMPROB;
530 break;
531 default:
532 goto badcode;
533 }
534 goto deliver;
535 break;
536
537 case ICMP6_ECHO_REQUEST:
538 icmp6_ifstat_inc(ifp, ifs6_in_echo);
539 if (code != 0)
540 goto badcode;
541 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
542 /* Give up remote */
543 break;
544 }
545 if (!M_WRITABLE(n)
546 || n->m_len < off + sizeof(struct icmp6_hdr)) {
547 struct mbuf *n0 = n;
548 int n0len;
549
550 CTASSERT(sizeof(*nip6) + sizeof(*nicmp6) <= MHLEN);
551 n = m_gethdr(M_NOWAIT, n0->m_type);
552 if (n == NULL) {
553 /* Give up remote */
554 m_freem(n0);
555 break;
556 }
557
558 m_move_pkthdr(n, n0); /* FIB copied. */
559 n0len = n0->m_pkthdr.len; /* save for use below */
560 /*
561 * Copy IPv6 and ICMPv6 only.
562 */
563 nip6 = mtod(n, struct ip6_hdr *);
564 bcopy(ip6, nip6, sizeof(struct ip6_hdr));
565 nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
566 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
567 noff = sizeof(struct ip6_hdr);
568 /* new mbuf contains only ipv6+icmpv6 headers */
569 n->m_len = noff + sizeof(struct icmp6_hdr);
570 /*
571 * Adjust mbuf. ip6_plen will be adjusted in
572 * ip6_output().
573 */
574 m_adj(n0, off + sizeof(struct icmp6_hdr));
575 /* recalculate complete packet size */
576 n->m_pkthdr.len = n0len + (noff - off);
577 n->m_next = n0;
578 } else {
579 if (n->m_len < off + sizeof(*nicmp6)) {
580 n = m_pullup(n, off + sizeof(*nicmp6));
581 if (n == NULL) {
582 IP6STAT_INC(ip6s_exthdrtoolong);
583 break;
584 }
585 }
586 nicmp6 = (struct icmp6_hdr *)(mtod(n, caddr_t) + off);
587 noff = off;
588 }
589 if (n) {
590 nicmp6->icmp6_type = ICMP6_ECHO_REPLY;
591 nicmp6->icmp6_code = 0;
592 ICMP6STAT_INC(icp6s_reflect);
593 ICMP6STAT_INC(icp6s_outhist[ICMP6_ECHO_REPLY]);
594 icmp6_reflect(n, noff);
595 }
596 break;
597
598 case ICMP6_ECHO_REPLY:
599 icmp6_ifstat_inc(ifp, ifs6_in_echoreply);
600 if (code != 0)
601 goto badcode;
602 break;
603
604 case MLD_LISTENER_QUERY:
605 case MLD_LISTENER_REPORT:
606 case MLD_LISTENER_DONE:
607 case MLDV2_LISTENER_REPORT:
608 /*
609 * Drop MLD traffic which is not link-local, has a hop limit
610 * of greater than 1 hop, or which does not have the
611 * IPv6 HBH Router Alert option.
612 * As IPv6 HBH options are stripped in ip6_input() we must
613 * check an mbuf header flag.
614 * XXX Should we also sanity check that these messages
615 * were directed to a link-local multicast prefix?
616 */
617 if ((ip6->ip6_hlim != 1) || (m->m_flags & M_RTALERT_MLD) == 0)
618 goto freeit;
619 if (mld_input(&m, off, icmp6len) != 0) {
620 *mp = NULL;
621 return (IPPROTO_DONE);
622 }
623 /* m stays. */
624 break;
625
626 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */
627 {
628 enum { WRU, FQDN } mode;
629 struct prison *pr;
630
631 if (!V_icmp6_nodeinfo)
632 break;
633
634 if (icmp6len == sizeof(struct icmp6_hdr) + 4)
635 mode = WRU;
636 else if (icmp6len >= sizeof(struct icmp6_nodeinfo))
637 mode = FQDN;
638 else
639 goto badlen;
640
641 pr = NULL;
642 sx_slock(&allprison_lock);
643 TAILQ_FOREACH(pr, &allprison, pr_list)
644 if (pr->pr_vnet == ifp->if_vnet)
645 break;
646 sx_sunlock(&allprison_lock);
647 if (pr == NULL)
648 pr = curthread->td_ucred->cr_prison;
649 if (mode == FQDN) {
650 if (m->m_len < off + sizeof(struct icmp6_nodeinfo)) {
651 m = m_pullup(m, off +
652 sizeof(struct icmp6_nodeinfo));
653 if (m == NULL) {
654 IP6STAT_INC(ip6s_exthdrtoolong);
655 *mp = m;
656 return (IPPROTO_DONE);
657 }
658 }
659 n = m_copym(m, 0, M_COPYALL, M_NOWAIT);
660 if (n)
661 n = ni6_input(n, off, pr);
662 /* XXX meaningless if n == NULL */
663 noff = sizeof(struct ip6_hdr);
664 } else {
665 u_char *p;
666 int maxhlen, hlen;
667
668 /*
669 * XXX: this combination of flags is pointless,
670 * but should we keep this for compatibility?
671 */
672 if ((V_icmp6_nodeinfo & (ICMP6_NODEINFO_FQDNOK |
673 ICMP6_NODEINFO_TMPADDROK)) !=
674 (ICMP6_NODEINFO_FQDNOK | ICMP6_NODEINFO_TMPADDROK))
675 break;
676
677 if (code != 0)
678 goto badcode;
679
680 CTASSERT(sizeof(*nip6) + sizeof(*nicmp6) + 4 <= MHLEN);
681 n = m_gethdr(M_NOWAIT, m->m_type);
682 if (n == NULL) {
683 /* Give up remote */
684 break;
685 }
686 if (!m_dup_pkthdr(n, m, M_NOWAIT)) {
687 /*
688 * Previous code did a blind M_COPY_PKTHDR
689 * and said "just for rcvif". If true, then
690 * we could tolerate the dup failing (due to
691 * the deep copy of the tag chain). For now
692 * be conservative and just fail.
693 */
694 m_free(n);
695 n = NULL;
696 break;
697 }
698 /*
699 * Copy IPv6 and ICMPv6 only.
700 */
701 nip6 = mtod(n, struct ip6_hdr *);
702 bcopy(ip6, nip6, sizeof(struct ip6_hdr));
703 nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
704 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
705 p = (u_char *)(nicmp6 + 1);
706 bzero(p, 4);
707
708 maxhlen = M_TRAILINGSPACE(n) -
709 (sizeof(*nip6) + sizeof(*nicmp6) + 4);
710 mtx_lock(&pr->pr_mtx);
711 hlen = strlen(pr->pr_hostname);
712 if (maxhlen > hlen)
713 maxhlen = hlen;
714 /* meaningless TTL */
715 bcopy(pr->pr_hostname, p + 4, maxhlen);
716 mtx_unlock(&pr->pr_mtx);
717 noff = sizeof(struct ip6_hdr);
718 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
719 sizeof(struct icmp6_hdr) + 4 + maxhlen;
720 nicmp6->icmp6_type = ICMP6_WRUREPLY;
721 nicmp6->icmp6_code = 0;
722 }
723 if (n) {
724 ICMP6STAT_INC(icp6s_reflect);
725 ICMP6STAT_INC(icp6s_outhist[ICMP6_WRUREPLY]);
726 icmp6_reflect(n, noff);
727 }
728 break;
729 }
730
731 case ICMP6_WRUREPLY:
732 if (code != 0)
733 goto badcode;
734 break;
735
736 case ND_ROUTER_SOLICIT:
737 icmp6_ifstat_inc(ifp, ifs6_in_routersolicit);
738 if (code != 0)
739 goto badcode;
740 if (icmp6len < sizeof(struct nd_router_solicit))
741 goto badlen;
742 if (send_sendso_input_hook != NULL) {
743 if (m->m_len < off + icmp6len) {
744 m = m_pullup(m, off + icmp6len);
745 if (m == NULL) {
746 IP6STAT_INC(ip6s_exthdrtoolong);
747 *mp = NULL;
748 return (IPPROTO_DONE);
749 }
750 }
751 error = send_sendso_input_hook(m, ifp, SND_IN, ip6len);
752 if (error == 0) {
753 m = NULL;
754 goto freeit;
755 }
756 }
757 n = m_copym(m, 0, M_COPYALL, M_NOWAIT);
758 nd6_rs_input(m, off, icmp6len);
759 m = n;
760 if (m == NULL)
761 goto freeit;
762 break;
763
764 case ND_ROUTER_ADVERT:
765 icmp6_ifstat_inc(ifp, ifs6_in_routeradvert);
766 if (code != 0)
767 goto badcode;
768 if (icmp6len < sizeof(struct nd_router_advert))
769 goto badlen;
770 if (send_sendso_input_hook != NULL) {
771 error = send_sendso_input_hook(m, ifp, SND_IN, ip6len);
772 if (error == 0) {
773 m = NULL;
774 goto freeit;
775 }
776 }
777 n = m_copym(m, 0, M_COPYALL, M_NOWAIT);
778 nd6_ra_input(m, off, icmp6len);
779 m = n;
780 if (m == NULL)
781 goto freeit;
782 break;
783
784 case ND_NEIGHBOR_SOLICIT:
785 icmp6_ifstat_inc(ifp, ifs6_in_neighborsolicit);
786 if (code != 0)
787 goto badcode;
788 if (icmp6len < sizeof(struct nd_neighbor_solicit))
789 goto badlen;
790 if (send_sendso_input_hook != NULL) {
791 error = send_sendso_input_hook(m, ifp, SND_IN, ip6len);
792 if (error == 0) {
793 m = NULL;
794 goto freeit;
795 }
796 }
797 n = m_copym(m, 0, M_COPYALL, M_NOWAIT);
798 nd6_ns_input(m, off, icmp6len);
799 m = n;
800 if (m == NULL)
801 goto freeit;
802 break;
803
804 case ND_NEIGHBOR_ADVERT:
805 icmp6_ifstat_inc(ifp, ifs6_in_neighboradvert);
806 if (code != 0)
807 goto badcode;
808 if (icmp6len < sizeof(struct nd_neighbor_advert))
809 goto badlen;
810 if (send_sendso_input_hook != NULL) {
811 error = send_sendso_input_hook(m, ifp, SND_IN, ip6len);
812 if (error == 0) {
813 m = NULL;
814 goto freeit;
815 }
816 }
817 n = m_copym(m, 0, M_COPYALL, M_NOWAIT);
818 nd6_na_input(m, off, icmp6len);
819 m = n;
820 if (m == NULL)
821 goto freeit;
822 break;
823
824 case ND_REDIRECT:
825 icmp6_ifstat_inc(ifp, ifs6_in_redirect);
826 if (code != 0)
827 goto badcode;
828 if (icmp6len < sizeof(struct nd_redirect))
829 goto badlen;
830 if (send_sendso_input_hook != NULL) {
831 error = send_sendso_input_hook(m, ifp, SND_IN, ip6len);
832 if (error == 0) {
833 m = NULL;
834 goto freeit;
835 }
836 }
837 n = m_copym(m, 0, M_COPYALL, M_NOWAIT);
838 icmp6_redirect_input(m, off);
839 m = n;
840 if (m == NULL)
841 goto freeit;
842 break;
843
844 case ICMP6_ROUTER_RENUMBERING:
845 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND &&
846 code != ICMP6_ROUTER_RENUMBERING_RESULT)
847 goto badcode;
848 if (icmp6len < sizeof(struct icmp6_router_renum))
849 goto badlen;
850 break;
851
852 default:
853 nd6log((LOG_DEBUG,
854 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n",
855 icmp6->icmp6_type, ip6_sprintf(ip6bufs, &ip6->ip6_src),
856 ip6_sprintf(ip6bufd, &ip6->ip6_dst),
857 ifp ? ifp->if_index : 0));
858 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) {
859 /* ICMPv6 error: MUST deliver it by spec... */
860 code = PRC_NCMDS;
861 /* deliver */
862 } else {
863 /* ICMPv6 informational: MUST not deliver */
864 break;
865 }
866 deliver:
867 if (icmp6_notify_error(&m, off, icmp6len, code) != 0) {
868 /* In this case, m should've been freed. */
869 *mp = NULL;
870 return (IPPROTO_DONE);
871 }
872 break;
873
874 badcode:
875 ICMP6STAT_INC(icp6s_badcode);
876 break;
877
878 badlen:
879 ICMP6STAT_INC(icp6s_badlen);
880 break;
881 }
882
883 /* deliver the packet to appropriate sockets */
884 icmp6_rip6_input(&m, *offp);
885
886 *mp = m;
887 return (IPPROTO_DONE);
888
889 freeit:
890 m_freem(m);
891 *mp = NULL;
892 return (IPPROTO_DONE);
893}
894
895static int
896icmp6_notify_error(struct mbuf **mp, int off, int icmp6len, int code)
897{
898 struct mbuf *m;
899 struct icmp6_hdr *icmp6;
900 struct ip6_hdr *eip6;
901 u_int32_t notifymtu;
902 struct sockaddr_in6 icmp6src, icmp6dst;
903
904 m = *mp;
905
906 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) {
907 ICMP6STAT_INC(icp6s_tooshort);
908 goto freeit;
909 }
910
911 if (m->m_len < off + sizeof(*icmp6) + sizeof(struct ip6_hdr)) {
912 m = m_pullup(m, off + sizeof(*icmp6) + sizeof(struct ip6_hdr));
913 if (m == NULL) {
914 IP6STAT_INC(ip6s_exthdrtoolong);
915 *mp = m;
916 return (-1);
917 }
918 }
919 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
920 eip6 = (struct ip6_hdr *)(icmp6 + 1);
921 bzero(&icmp6dst, sizeof(icmp6dst));
922
923 /* Detect the upper level protocol */
924 {
925 void (*ctlfunc)(int, struct sockaddr *, void *);
926 u_int8_t nxt = eip6->ip6_nxt;
927 int eoff = off + sizeof(struct icmp6_hdr) +
928 sizeof(struct ip6_hdr);
929 struct ip6ctlparam ip6cp;
930 int icmp6type = icmp6->icmp6_type;
931 struct ip6_frag *fh;
932 struct ip6_rthdr *rth;
933 struct ip6_rthdr0 *rth0;
934 int rthlen;
935
936 while (1) { /* XXX: should avoid infinite loop explicitly? */
937 struct ip6_ext *eh;
938
939 switch (nxt) {
940 case IPPROTO_HOPOPTS:
941 case IPPROTO_DSTOPTS:
942 case IPPROTO_AH:
943 if (m->m_len < eoff + sizeof(struct ip6_ext)) {
944 m = m_pullup(m, eoff +
945 sizeof(struct ip6_ext));
946 if (m == NULL) {
947 IP6STAT_INC(ip6s_exthdrtoolong);
948 *mp = m;
949 return (-1);
950 }
951 }
952 eh = (struct ip6_ext *)
953 (mtod(m, caddr_t) + eoff);
954 if (nxt == IPPROTO_AH)
955 eoff += (eh->ip6e_len + 2) << 2;
956 else
957 eoff += (eh->ip6e_len + 1) << 3;
958 nxt = eh->ip6e_nxt;
959 break;
960 case IPPROTO_ROUTING:
961 /*
962 * When the erroneous packet contains a
963 * routing header, we should examine the
964 * header to determine the final destination.
965 * Otherwise, we can't properly update
966 * information that depends on the final
967 * destination (e.g. path MTU).
968 */
969 if (m->m_len < eoff + sizeof(*rth)) {
970 m = m_pullup(m, eoff + sizeof(*rth));
971 if (m == NULL) {
972 IP6STAT_INC(ip6s_exthdrtoolong);
973 *mp = m;
974 return (-1);
975 }
976 }
977 rth = (struct ip6_rthdr *)
978 (mtod(m, caddr_t) + eoff);
979 rthlen = (rth->ip6r_len + 1) << 3;
980 /*
981 * XXX: currently there is no
982 * officially defined type other
983 * than type-0.
984 * Note that if the segment left field
985 * is 0, all intermediate hops must
986 * have been passed.
987 */
988 if (rth->ip6r_segleft &&
989 rth->ip6r_type == IPV6_RTHDR_TYPE_0) {
990 int hops;
991
992 if (m->m_len < eoff + rthlen) {
993 m = m_pullup(m, eoff + rthlen);
994 if (m == NULL) {
995 IP6STAT_INC(
996 ip6s_exthdrtoolong);
997 *mp = m;
998 return (-1);
999 }
1000 }
1001 rth0 = (struct ip6_rthdr0 *)
1002 (mtod(m, caddr_t) + eoff);
1003
1004 /* just ignore a bogus header */
1005 if ((rth0->ip6r0_len % 2) == 0 &&
1006 (hops = rth0->ip6r0_len/2))
1007 icmp6dst.sin6_addr = *((struct in6_addr *)(rth0 + 1) + (hops - 1));
1008 }
1009 eoff += rthlen;
1010 nxt = rth->ip6r_nxt;
1011 break;
1012 case IPPROTO_FRAGMENT:
1013 if (m->m_len < eoff + sizeof(struct ip6_frag)) {
1014 m = m_pullup(m, eoff +
1015 sizeof(struct ip6_frag));
1016 if (m == NULL) {
1017 IP6STAT_INC(ip6s_exthdrtoolong);
1018 *mp = m;
1019 return (-1);
1020 }
1021 }
1022 fh = (struct ip6_frag *)(mtod(m, caddr_t) +
1023 eoff);
1024 /*
1025 * Data after a fragment header is meaningless
1026 * unless it is the first fragment, but
1027 * we'll go to the notify label for path MTU
1028 * discovery.
1029 */
1030 if (fh->ip6f_offlg & IP6F_OFF_MASK)
1031 goto notify;
1032
1033 eoff += sizeof(struct ip6_frag);
1034 nxt = fh->ip6f_nxt;
1035 break;
1036 default:
1037 /*
1038 * This case includes ESP and the No Next
1039 * Header. In such cases going to the notify
1040 * label does not have any meaning
1041 * (i.e. ctlfunc will be NULL), but we go
1042 * anyway since we might have to update
1043 * path MTU information.
1044 */
1045 goto notify;
1046 }
1047 }
1048 notify:
1049 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
1050
1051 /*
1052 * retrieve parameters from the inner IPv6 header, and convert
1053 * them into sockaddr structures.
1054 * XXX: there is no guarantee that the source or destination
1055 * addresses of the inner packet are in the same scope as
1056 * the addresses of the icmp packet. But there is no other
1057 * way to determine the zone.
1058 */
1059 eip6 = (struct ip6_hdr *)(icmp6 + 1);
1060
1061 icmp6dst.sin6_len = sizeof(struct sockaddr_in6);
1062 icmp6dst.sin6_family = AF_INET6;
1063 if (IN6_IS_ADDR_UNSPECIFIED(&icmp6dst.sin6_addr))
1064 icmp6dst.sin6_addr = eip6->ip6_dst;
1065 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL))
1066 goto freeit;
1067 bzero(&icmp6src, sizeof(icmp6src));
1068 icmp6src.sin6_len = sizeof(struct sockaddr_in6);
1069 icmp6src.sin6_family = AF_INET6;
1070 icmp6src.sin6_addr = eip6->ip6_src;
1071 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL))
1072 goto freeit;
1073 icmp6src.sin6_flowinfo =
1074 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK);
1075
1076 ip6cp.ip6c_m = m;
1077 ip6cp.ip6c_icmp6 = icmp6;
1078 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1);
1079 ip6cp.ip6c_off = eoff;
1080 ip6cp.ip6c_finaldst = &icmp6dst.sin6_addr;
1081 ip6cp.ip6c_src = &icmp6src;
1082 ip6cp.ip6c_nxt = nxt;
1083
1084 if (icmp6type == ICMP6_PACKET_TOO_BIG) {
1085 notifymtu = ntohl(icmp6->icmp6_mtu);
1086 ip6cp.ip6c_cmdarg = (void *)&notifymtu;
1087 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/
1088 }
1089
1090 ctlfunc = (void (*)(int, struct sockaddr *, void *))
1091 (inet6sw[ip6_protox[nxt]].pr_ctlinput);
1092 if (ctlfunc) {
1093 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst,
1094 &ip6cp);
1095 }
1096 }
1097 *mp = m;
1098 return (0);
1099
1100 freeit:
1101 m_freem(m);
1102 *mp = NULL;
1103 return (-1);
1104}
1105
1106void
1107icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated)
1108{
1109 struct in6_addr *dst = ip6cp->ip6c_finaldst;
1110 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6;
1111 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */
1112 u_int mtu = ntohl(icmp6->icmp6_mtu);
1113 struct in_conninfo inc;
1114
1115#if 0
1116 /*
1117 * RFC2460 section 5, last paragraph.
1118 * even though minimum link MTU for IPv6 is IPV6_MMTU,
1119 * we may see ICMPv6 too big with mtu < IPV6_MMTU
1120 * due to packet translator in the middle.
1121 * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for
1122 * special handling.
1123 */
1124 if (mtu < IPV6_MMTU)
1125 return;
1126#endif
1127
1128 /*
1129 * we reject ICMPv6 too big with abnormally small value.
1130 * XXX what is the good definition of "abnormally small"?
1131 */
1132 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8)
1133 return;
1134
1135 if (!validated)
1136 return;
1137
1138 /*
1139 * In case the suggested mtu is less than IPV6_MMTU, we
1140 * only need to remember that it was for above mentioned
1141 * "alwaysfrag" case.
1142 * Try to be as close to the spec as possible.
1143 */
1144 if (mtu < IPV6_MMTU)
1145 mtu = IPV6_MMTU - 8;
1146
1147 bzero(&inc, sizeof(inc));
1148 inc.inc_fibnum = M_GETFIB(m);
1149 inc.inc_flags |= INC_ISIPV6;
1150 inc.inc6_faddr = *dst;
1151 if (in6_setscope(&inc.inc6_faddr, m->m_pkthdr.rcvif, NULL))
1152 return;
1153
1154 if (mtu < tcp_maxmtu6(&inc, NULL)) {
1155 tcp_hc_updatemtu(&inc, mtu);
1156 ICMP6STAT_INC(icp6s_pmtuchg);
1157 }
1158}
1159
1160/*
1161 * Process a Node Information Query packet, based on
1162 * draft-ietf-ipngwg-icmp-name-lookups-07.
1163 *
1164 * Spec incompatibilities:
1165 * - IPv6 Subject address handling
1166 * - IPv4 Subject address handling support missing
1167 * - Proxy reply (answer even if it's not for me)
1168 * - joins NI group address at in6_ifattach() time only, does not cope
1169 * with hostname changes by sethostname(3)
1170 */
1171static struct mbuf *
1172ni6_input(struct mbuf *m, int off, struct prison *pr)
1173{
1174 struct icmp6_nodeinfo *ni6, *nni6;
1175 struct mbuf *n = NULL;
1176 u_int16_t qtype;
1177 int subjlen;
1178 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
1179 struct ni_reply_fqdn *fqdn;
1180 int addrs; /* for NI_QTYPE_NODEADDR */
1181 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */
1182 struct in6_addr in6_subj; /* subject address */
1183 struct ip6_hdr *ip6;
1184 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */
1185 char *subj = NULL;
1186 struct in6_ifaddr *ia6 = NULL;
1187
1188 ip6 = mtod(m, struct ip6_hdr *);
1189 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off);
1190
1191 /*
1192 * Validate IPv6 source address.
1193 * The default configuration MUST be to refuse answering queries from
1194 * global-scope addresses according to RFC4602.
1195 * Notes:
1196 * - it's not very clear what "refuse" means; this implementation
1197 * simply drops it.
1198 * - it's not very easy to identify global-scope (unicast) addresses
1199 * since there are many prefixes for them. It should be safer
1200 * and in practice sufficient to check "all" but loopback and
1201 * link-local (note that site-local unicast was deprecated and
1202 * ULA is defined as global scope-wise)
1203 */
1204 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_GLOBALOK) == 0 &&
1205 !IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) &&
1206 !IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src))
1207 goto bad;
1208
1209 /*
1210 * Validate IPv6 destination address.
1211 *
1212 * The Responder must discard the Query without further processing
1213 * unless it is one of the Responder's unicast or anycast addresses, or
1214 * a link-local scope multicast address which the Responder has joined.
1215 * [RFC4602, Section 5.]
1216 */
1217 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
1218 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst))
1219 goto bad;
1220 /* else it's a link-local multicast, fine */
1221 } else { /* unicast or anycast */
1222 ia6 = in6ifa_ifwithaddr(&ip6->ip6_dst, 0 /* XXX */, false);
1223 if (ia6 == NULL)
1224 goto bad; /* XXX impossible */
1225
1226 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) &&
1227 !(V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK)) {
1228 nd6log((LOG_DEBUG, "ni6_input: ignore node info to "
1229 "a temporary address in %s:%d",
1230 __FILE__, __LINE__));
1231 goto bad;
1232 }
1233 }
1234
1235 /* validate query Subject field. */
1236 qtype = ntohs(ni6->ni_qtype);
1237 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo);
1238 switch (qtype) {
1239 case NI_QTYPE_NOOP:
1240 case NI_QTYPE_SUPTYPES:
1241 /* 07 draft */
1242 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0)
1243 break;
1244 /* FALLTHROUGH */
1245 case NI_QTYPE_FQDN:
1246 case NI_QTYPE_NODEADDR:
1247 case NI_QTYPE_IPV4ADDR:
1248 switch (ni6->ni_code) {
1249 case ICMP6_NI_SUBJ_IPV6:
1250#if ICMP6_NI_SUBJ_IPV6 != 0
1251 case 0:
1252#endif
1253 /*
1254 * backward compatibility - try to accept 03 draft
1255 * format, where no Subject is present.
1256 */
1257 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 &&
1258 subjlen == 0) {
1259 oldfqdn++;
1260 break;
1261 }
1262#if ICMP6_NI_SUBJ_IPV6 != 0
1263 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6)
1264 goto bad;
1265#endif
1266
1267 if (subjlen != sizeof(struct in6_addr))
1268 goto bad;
1269
1270 /*
1271 * Validate Subject address.
1272 *
1273 * Not sure what exactly "address belongs to the node"
1274 * means in the spec, is it just unicast, or what?
1275 *
1276 * At this moment we consider Subject address as
1277 * "belong to the node" if the Subject address equals
1278 * to the IPv6 destination address; validation for
1279 * IPv6 destination address should have done enough
1280 * check for us.
1281 *
1282 * We do not do proxy at this moment.
1283 */
1284 m_copydata(m, off + sizeof(struct icmp6_nodeinfo),
1285 subjlen, (caddr_t)&in6_subj);
1286 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL))
1287 goto bad;
1288
1289 subj = (char *)&in6_subj;
1290 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj))
1291 break;
1292
1293 /*
1294 * XXX if we are to allow other cases, we should really
1295 * be careful about scope here.
1296 * basically, we should disallow queries toward IPv6
1297 * destination X with subject Y,
1298 * if scope(X) > scope(Y).
1299 * if we allow scope(X) > scope(Y), it will result in
1300 * information leakage across scope boundary.
1301 */
1302 goto bad;
1303
1304 case ICMP6_NI_SUBJ_FQDN:
1305 /*
1306 * Validate Subject name with gethostname(3).
1307 *
1308 * The behavior may need some debate, since:
1309 * - we are not sure if the node has FQDN as
1310 * hostname (returned by gethostname(3)).
1311 * - the code does wildcard match for truncated names.
1312 * however, we are not sure if we want to perform
1313 * wildcard match, if gethostname(3) side has
1314 * truncated hostname.
1315 */
1316 mtx_lock(&pr->pr_mtx);
1317 n = ni6_nametodns(pr->pr_hostname,
1318 strlen(pr->pr_hostname), 0);
1319 mtx_unlock(&pr->pr_mtx);
1320 if (!n || n->m_next || n->m_len == 0)
1321 goto bad;
1322 if (m->m_len < off + sizeof(struct icmp6_nodeinfo) +
1323 subjlen) {
1324 m = m_pullup(m, off +
1325 sizeof(struct icmp6_nodeinfo) + subjlen);
1326 if (m == NULL) {
1327 IP6STAT_INC(ip6s_exthdrtoolong);
1328 goto bad;
1329 }
1330 }
1331 /* ip6 possibly invalid but not used after. */
1332 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off);
1333 subj = (char *)(mtod(m, caddr_t) + off +
1334 sizeof(struct icmp6_nodeinfo));
1335 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *),
1336 n->m_len)) {
1337 goto bad;
1338 }
1339 m_freem(n);
1340 n = NULL;
1341 break;
1342
1343 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */
1344 default:
1345 goto bad;
1346 }
1347 break;
1348 }
1349
1350 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */
1351 switch (qtype) {
1352 case NI_QTYPE_FQDN:
1353 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_FQDNOK) == 0)
1354 goto bad;
1355 break;
1356 case NI_QTYPE_NODEADDR:
1357 case NI_QTYPE_IPV4ADDR:
1358 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_NODEADDROK) == 0)
1359 goto bad;
1360 break;
1361 }
1362
1363 /* guess reply length */
1364 switch (qtype) {
1365 case NI_QTYPE_NOOP:
1366 break; /* no reply data */
1367 case NI_QTYPE_SUPTYPES:
1368 replylen += sizeof(u_int32_t);
1369 break;
1370 case NI_QTYPE_FQDN:
1371 /* XXX will append an mbuf */
1372 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1373 break;
1374 case NI_QTYPE_NODEADDR:
1375 addrs = ni6_addrs(ni6, m, &ifp, (struct in6_addr *)subj);
1376 if ((replylen += addrs * (sizeof(struct in6_addr) +
1377 sizeof(u_int32_t))) > MCLBYTES)
1378 replylen = MCLBYTES; /* XXX: will truncate pkt later */
1379 break;
1380 case NI_QTYPE_IPV4ADDR:
1381 /* unsupported - should respond with unknown Qtype? */
1382 break;
1383 default:
1384 /*
1385 * XXX: We must return a reply with the ICMP6 code
1386 * `unknown Qtype' in this case. However we regard the case
1387 * as an FQDN query for backward compatibility.
1388 * Older versions set a random value to this field,
1389 * so it rarely varies in the defined qtypes.
1390 * But the mechanism is not reliable...
1391 * maybe we should obsolete older versions.
1392 */
1393 qtype = NI_QTYPE_FQDN;
1394 /* XXX will append an mbuf */
1395 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1396 oldfqdn++;
1397 break;
1398 }
1399
1400 /* Allocate an mbuf to reply. */
1401 if (replylen > MCLBYTES) {
1402 /*
1403 * XXX: should we try to allocate more? But MCLBYTES
1404 * is probably much larger than IPV6_MMTU...
1405 */
1406 goto bad;
1407 }
1408 if (replylen > MHLEN)
1409 n = m_getcl(M_NOWAIT, m->m_type, M_PKTHDR);
1410 else
1411 n = m_gethdr(M_NOWAIT, m->m_type);
1412 if (n == NULL) {
1413 m_freem(m);
1414 return (NULL);
1415 }
1416 m_move_pkthdr(n, m); /* just for recvif and FIB */
1417 n->m_pkthdr.len = n->m_len = replylen;
1418
1419 /* copy mbuf header and IPv6 + Node Information base headers */
1420 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr));
1421 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1);
1422 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo));
1423
1424 /* qtype dependent procedure */
1425 switch (qtype) {
1426 case NI_QTYPE_NOOP:
1427 nni6->ni_code = ICMP6_NI_SUCCESS;
1428 nni6->ni_flags = 0;
1429 break;
1430 case NI_QTYPE_SUPTYPES:
1431 {
1432 u_int32_t v;
1433 nni6->ni_code = ICMP6_NI_SUCCESS;
1434 nni6->ni_flags = htons(0x0000); /* raw bitmap */
1435 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */
1436 v = (u_int32_t)htonl(0x0000000f);
1437 bcopy(&v, nni6 + 1, sizeof(u_int32_t));
1438 break;
1439 }
1440 case NI_QTYPE_FQDN:
1441 nni6->ni_code = ICMP6_NI_SUCCESS;
1442 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) +
1443 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo));
1444 nni6->ni_flags = 0; /* XXX: meaningless TTL */
1445 fqdn->ni_fqdn_ttl = 0; /* ditto. */
1446 /*
1447 * XXX do we really have FQDN in hostname?
1448 */
1449 mtx_lock(&pr->pr_mtx);
1450 n->m_next = ni6_nametodns(pr->pr_hostname,
1451 strlen(pr->pr_hostname), oldfqdn);
1452 mtx_unlock(&pr->pr_mtx);
1453 if (n->m_next == NULL)
1454 goto bad;
1455 /* XXX we assume that n->m_next is not a chain */
1456 if (n->m_next->m_next != NULL)
1457 goto bad;
1458 n->m_pkthdr.len += n->m_next->m_len;
1459 break;
1460 case NI_QTYPE_NODEADDR:
1461 {
1462 int lenlim, copied;
1463
1464 nni6->ni_code = ICMP6_NI_SUCCESS;
1465 n->m_pkthdr.len = n->m_len =
1466 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
1467 lenlim = M_TRAILINGSPACE(n);
1468 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim);
1469 /* XXX: reset mbuf length */
1470 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
1471 sizeof(struct icmp6_nodeinfo) + copied;
1472 break;
1473 }
1474 default:
1475 break; /* XXX impossible! */
1476 }
1477
1478 nni6->ni_type = ICMP6_NI_REPLY;
1479 m_freem(m);
1480 return (n);
1481
1482 bad:
1483 m_freem(m);
1484 if (n)
1485 m_freem(n);
1486 return (NULL);
1487}
1488
1489/*
1490 * make a mbuf with DNS-encoded string. no compression support.
1491 *
1492 * XXX names with less than 2 dots (like "foo" or "foo.section") will be
1493 * treated as truncated name (two \0 at the end). this is a wild guess.
1494 *
1495 * old - return pascal string if non-zero
1496 */
1497static struct mbuf *
1498ni6_nametodns(const char *name, int namelen, int old)
1499{
1500 struct mbuf *m;
1501 char *cp, *ep;
1502 const char *p, *q;
1503 int i, len, nterm;
1504
1505 if (old)
1506 len = namelen + 1;
1507 else
1508 len = MCLBYTES;
1509
1510 /* Because MAXHOSTNAMELEN is usually 256, we use cluster mbuf. */
1511 if (len > MLEN)
1512 m = m_getcl(M_NOWAIT, MT_DATA, 0);
1513 else
1514 m = m_get(M_NOWAIT, MT_DATA);
1515 if (m == NULL)
1516 goto fail;
1517
1518 if (old) {
1519 m->m_len = len;
1520 *mtod(m, char *) = namelen;
1521 bcopy(name, mtod(m, char *) + 1, namelen);
1522 return m;
1523 } else {
1524 m->m_len = 0;
1525 cp = mtod(m, char *);
1526 ep = mtod(m, char *) + M_TRAILINGSPACE(m);
1527
1528 /* if not certain about my name, return empty buffer */
1529 if (namelen == 0)
1530 return m;
1531
1532 /*
1533 * guess if it looks like shortened hostname, or FQDN.
1534 * shortened hostname needs two trailing "\0".
1535 */
1536 i = 0;
1537 for (p = name; p < name + namelen; p++) {
1538 if (*p && *p == '.')
1539 i++;
1540 }
1541 if (i < 2)
1542 nterm = 2;
1543 else
1544 nterm = 1;
1545
1546 p = name;
1547 while (cp < ep && p < name + namelen) {
1548 i = 0;
1549 for (q = p; q < name + namelen && *q && *q != '.'; q++)
1550 i++;
1551 /* result does not fit into mbuf */
1552 if (cp + i + 1 >= ep)
1553 goto fail;
1554 /*
1555 * DNS label length restriction, RFC1035 page 8.
1556 * "i == 0" case is included here to avoid returning
1557 * 0-length label on "foo..bar".
1558 */
1559 if (i <= 0 || i >= 64)
1560 goto fail;
1561 *cp++ = i;
1562 bcopy(p, cp, i);
1563 cp += i;
1564 p = q;
1565 if (p < name + namelen && *p == '.')
1566 p++;
1567 }
1568 /* termination */
1569 if (cp + nterm >= ep)
1570 goto fail;
1571 while (nterm-- > 0)
1572 *cp++ = '\0';
1573 m->m_len = cp - mtod(m, char *);
1574 return m;
1575 }
1576
1577 panic("should not reach here");
1578 /* NOTREACHED */
1579
1580 fail:
1581 if (m)
1582 m_freem(m);
1583 return NULL;
1584}
1585
1586/*
1587 * check if two DNS-encoded string matches. takes care of truncated
1588 * form (with \0\0 at the end). no compression support.
1589 * XXX upper/lowercase match (see RFC2065)
1590 */
1591static int
1592ni6_dnsmatch(const char *a, int alen, const char *b, int blen)
1593{
1594 const char *a0, *b0;
1595 int l;
1596
1597 /* simplest case - need validation? */
1598 if (alen == blen && bcmp(a, b, alen) == 0)
1599 return 1;
1600
1601 a0 = a;
1602 b0 = b;
1603
1604 /* termination is mandatory */
1605 if (alen < 2 || blen < 2)
1606 return 0;
1607 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0')
1608 return 0;
1609 alen--;
1610 blen--;
1611
1612 while (a - a0 < alen && b - b0 < blen) {
1613 if (a - a0 + 1 > alen || b - b0 + 1 > blen)
1614 return 0;
1615
1616 if ((signed char)a[0] < 0 || (signed char)b[0] < 0)
1617 return 0;
1618 /* we don't support compression yet */
1619 if (a[0] >= 64 || b[0] >= 64)
1620 return 0;
1621
1622 /* truncated case */
1623 if (a[0] == 0 && a - a0 == alen - 1)
1624 return 1;
1625 if (b[0] == 0 && b - b0 == blen - 1)
1626 return 1;
1627 if (a[0] == 0 || b[0] == 0)
1628 return 0;
1629
1630 if (a[0] != b[0])
1631 return 0;
1632 l = a[0];
1633 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen)
1634 return 0;
1635 if (bcmp(a + 1, b + 1, l) != 0)
1636 return 0;
1637
1638 a += 1 + l;
1639 b += 1 + l;
1640 }
1641
1642 if (a - a0 == alen && b - b0 == blen)
1643 return 1;
1644 else
1645 return 0;
1646}
1647
1648/*
1649 * calculate the number of addresses to be returned in the node info reply.
1650 */
1651static int
1652ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, struct ifnet **ifpp,
1653 struct in6_addr *subj)
1654{
1655 struct ifnet *ifp;
1656 struct in6_ifaddr *ifa6;
1657 struct ifaddr *ifa;
1658 int addrs = 0, addrsofif, iffound = 0;
1659 int niflags = ni6->ni_flags;
1660
1661 NET_EPOCH_ASSERT();
1662
1663 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) {
1664 switch (ni6->ni_code) {
1665 case ICMP6_NI_SUBJ_IPV6:
1666 if (subj == NULL) /* must be impossible... */
1667 return (0);
1668 break;
1669 default:
1670 /*
1671 * XXX: we only support IPv6 subject address for
1672 * this Qtype.
1673 */
1674 return (0);
1675 }
1676 }
1677
1678 CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link) {
1679 addrsofif = 0;
1680 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1681 if (ifa->ifa_addr->sa_family != AF_INET6)
1682 continue;
1683 ifa6 = (struct in6_ifaddr *)ifa;
1684
1685 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 &&
1686 IN6_ARE_ADDR_EQUAL(subj, &ifa6->ia_addr.sin6_addr))
1687 iffound = 1;
1688
1689 /*
1690 * IPv4-mapped addresses can only be returned by a
1691 * Node Information proxy, since they represent
1692 * addresses of IPv4-only nodes, which perforce do
1693 * not implement this protocol.
1694 * [icmp-name-lookups-07, Section 5.4]
1695 * So we don't support NI_NODEADDR_FLAG_COMPAT in
1696 * this function at this moment.
1697 */
1698
1699 /* What do we have to do about ::1? */
1700 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
1701 case IPV6_ADDR_SCOPE_LINKLOCAL:
1702 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
1703 continue;
1704 break;
1705 case IPV6_ADDR_SCOPE_SITELOCAL:
1706 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
1707 continue;
1708 break;
1709 case IPV6_ADDR_SCOPE_GLOBAL:
1710 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
1711 continue;
1712 break;
1713 default:
1714 continue;
1715 }
1716
1717 /*
1718 * check if anycast is okay.
1719 * XXX: just experimental. not in the spec.
1720 */
1721 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 &&
1722 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0)
1723 continue; /* we need only unicast addresses */
1724 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
1725 (V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) {
1726 continue;
1727 }
1728 addrsofif++; /* count the address */
1729 }
1730 if (iffound) {
1731 *ifpp = ifp;
1732 return (addrsofif);
1733 }
1734
1735 addrs += addrsofif;
1736 }
1737
1738 return (addrs);
1739}
1740
1741static int
1742ni6_store_addrs(struct icmp6_nodeinfo *ni6, struct icmp6_nodeinfo *nni6,
1743 struct ifnet *ifp0, int resid)
1744{
1745 struct ifnet *ifp;
1746 struct in6_ifaddr *ifa6;
1747 struct ifaddr *ifa;
1748 struct ifnet *ifp_dep = NULL;
1749 int copied = 0, allow_deprecated = 0;
1750 u_char *cp = (u_char *)(nni6 + 1);
1751 int niflags = ni6->ni_flags;
1752 u_int32_t ltime;
1753
1754 NET_EPOCH_ASSERT();
1755
1756 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL))
1757 return (0); /* needless to copy */
1758
1759 ifp = ifp0 ? ifp0 : CK_STAILQ_FIRST(&V_ifnet);
1760 again:
1761
1762 for (; ifp; ifp = CK_STAILQ_NEXT(ifp, if_link)) {
1763 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1764 if (ifa->ifa_addr->sa_family != AF_INET6)
1765 continue;
1766 ifa6 = (struct in6_ifaddr *)ifa;
1767
1768 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 &&
1769 allow_deprecated == 0) {
1770 /*
1771 * prefererred address should be put before
1772 * deprecated addresses.
1773 */
1774
1775 /* record the interface for later search */
1776 if (ifp_dep == NULL)
1777 ifp_dep = ifp;
1778
1779 continue;
1780 } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 &&
1781 allow_deprecated != 0)
1782 continue; /* we now collect deprecated addrs */
1783
1784 /* What do we have to do about ::1? */
1785 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
1786 case IPV6_ADDR_SCOPE_LINKLOCAL:
1787 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
1788 continue;
1789 break;
1790 case IPV6_ADDR_SCOPE_SITELOCAL:
1791 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
1792 continue;
1793 break;
1794 case IPV6_ADDR_SCOPE_GLOBAL:
1795 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
1796 continue;
1797 break;
1798 default:
1799 continue;
1800 }
1801
1802 /*
1803 * check if anycast is okay.
1804 * XXX: just experimental. not in the spec.
1805 */
1806 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 &&
1807 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0)
1808 continue;
1809 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
1810 (V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) {
1811 continue;
1812 }
1813
1814 /* now we can copy the address */
1815 if (resid < sizeof(struct in6_addr) +
1816 sizeof(u_int32_t)) {
1817 /*
1818 * We give up much more copy.
1819 * Set the truncate flag and return.
1820 */
1821 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE;
1822 return (copied);
1823 }
1824
1825 /*
1826 * Set the TTL of the address.
1827 * The TTL value should be one of the following
1828 * according to the specification:
1829 *
1830 * 1. The remaining lifetime of a DHCP lease on the
1831 * address, or
1832 * 2. The remaining Valid Lifetime of a prefix from
1833 * which the address was derived through Stateless
1834 * Autoconfiguration.
1835 *
1836 * Note that we currently do not support stateful
1837 * address configuration by DHCPv6, so the former
1838 * case can't happen.
1839 */
1840 if (ifa6->ia6_lifetime.ia6t_expire == 0)
1841 ltime = ND6_INFINITE_LIFETIME;
1842 else {
1843 if (ifa6->ia6_lifetime.ia6t_expire >
1844 time_uptime)
1845 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_uptime);
1846 else
1847 ltime = 0;
1848 }
1849
1850 bcopy(&ltime, cp, sizeof(u_int32_t));
1851 cp += sizeof(u_int32_t);
1852
1853 /* copy the address itself */
1854 bcopy(&ifa6->ia_addr.sin6_addr, cp,
1855 sizeof(struct in6_addr));
1856 in6_clearscope((struct in6_addr *)cp); /* XXX */
1857 cp += sizeof(struct in6_addr);
1858
1859 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t));
1860 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t));
1861 }
1862 if (ifp0) /* we need search only on the specified IF */
1863 break;
1864 }
1865
1866 if (allow_deprecated == 0 && ifp_dep != NULL) {
1867 ifp = ifp_dep;
1868 allow_deprecated = 1;
1869
1870 goto again;
1871 }
1872
1873 return (copied);
1874}
1875
1876static bool
1877icmp6_rip6_match(const struct inpcb *inp, void *v)
1878{
1879 struct ip6_hdr *ip6 = v;
1880
1881 if ((inp->inp_vflag & INP_IPV6) == 0)
1882 return (false);
1883 if (inp->inp_ip_p != IPPROTO_ICMPV6)
1884 return (false);
1885 if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) &&
1886 !IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr, &ip6->ip6_dst))
1887 return (false);
1888 if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr) &&
1889 !IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr, &ip6->ip6_src))
1890 return (false);
1891 return (true);
1892}
1893
1894/*
1895 * XXX almost dup'ed code with rip6_input.
1896 */
1897static int
1898icmp6_rip6_input(struct mbuf **mp, int off)
1899{
1900 struct mbuf *n, *m = *mp;
1901 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1902 struct inpcb_iterator inpi = INP_ITERATOR(&V_ripcbinfo,
1903 INPLOOKUP_RLOCKPCB, icmp6_rip6_match, ip6);
1904 struct inpcb *inp;
1905 struct sockaddr_in6 fromsa;
1906 struct icmp6_hdr *icmp6;
1907 struct mbuf *opts = NULL;
1908 int delivered = 0;
1909
1910 /* This is assumed to be safe; icmp6_input() does a pullup. */
1911 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
1912
1913 /*
1914 * XXX: the address may have embedded scope zone ID, which should be
1915 * hidden from applications.
1916 */
1917 bzero(&fromsa, sizeof(fromsa));
1918 fromsa.sin6_family = AF_INET6;
1919 fromsa.sin6_len = sizeof(struct sockaddr_in6);
1920 fromsa.sin6_addr = ip6->ip6_src;
1921 if (sa6_recoverscope(&fromsa)) {
1922 m_freem(m);
1923 *mp = NULL;
1924 return (IPPROTO_DONE);
1925 }
1926
1927 while ((inp = inp_next(&inpi)) != NULL) {
1928 if (ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type,
1929 inp->in6p_icmp6filt))
1930 continue;
1931 /*
1932 * Recent network drivers tend to allocate a single
1933 * mbuf cluster, rather than to make a couple of
1934 * mbufs without clusters. Also, since the IPv6 code
1935 * path tries to avoid m_pullup(), it is highly
1936 * probable that we still have an mbuf cluster here
1937 * even though the necessary length can be stored in an
1938 * mbuf's internal buffer.
1939 * Meanwhile, the default size of the receive socket
1940 * buffer for raw sockets is not so large. This means
1941 * the possibility of packet loss is relatively higher
1942 * than before. To avoid this scenario, we copy the
1943 * received data to a separate mbuf that does not use
1944 * a cluster, if possible.
1945 * XXX: it is better to copy the data after stripping
1946 * intermediate headers.
1947 */
1948 if ((m->m_flags & M_EXT) && m->m_next == NULL &&
1949 m->m_len <= MHLEN) {
1950 n = m_get(M_NOWAIT, m->m_type);
1951 if (n != NULL) {
1952 if (m_dup_pkthdr(n, m, M_NOWAIT)) {
1953 bcopy(m->m_data, n->m_data, m->m_len);
1954 n->m_len = m->m_len;
1955 } else {
1956 m_free(n);
1957 n = NULL;
1958 }
1959 }
1960 } else
1961 n = m_copym(m, 0, M_COPYALL, M_NOWAIT);
1962 if (n == NULL)
1963 continue;
1964 if (inp->inp_flags & INP_CONTROLOPTS)
1965 ip6_savecontrol(inp, n, &opts);
1966 /* strip intermediate headers */
1967 m_adj(n, off);
1968 SOCKBUF_LOCK(&inp->inp_socket->so_rcv);
1969 if (sbappendaddr_locked(&inp->inp_socket->so_rcv,
1970 (struct sockaddr *)&fromsa, n, opts) == 0) {
1971 soroverflow_locked(inp->inp_socket);
1972 m_freem(n);
1973 if (opts)
1974 m_freem(opts);
1975 } else {
1976 sorwakeup_locked(inp->inp_socket);
1977 delivered++;
1978 }
1979 opts = NULL;
1980 }
1981 m_freem(m);
1982 *mp = NULL;
1983 if (delivered == 0)
1984 IP6STAT_DEC(ip6s_delivered);
1985 return (IPPROTO_DONE);
1986}
1987
1988/*
1989 * Reflect the ip6 packet back to the source.
1990 * OFF points to the icmp6 header, counted from the top of the mbuf.
1991 */
1992static void
1993icmp6_reflect(struct mbuf *m, size_t off)
1994{
1995 struct in6_addr src6, *srcp;
1996 struct ip6_hdr *ip6;
1997 struct icmp6_hdr *icmp6;
1998 struct in6_ifaddr *ia = NULL;
1999 struct ifnet *outif = NULL;
2000 int plen;
2001 int type, code, hlim;
2002
2003 /* too short to reflect */
2004 if (off < sizeof(struct ip6_hdr)) {
2005 nd6log((LOG_DEBUG,
2006 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n",
2007 (u_long)off, (u_long)sizeof(struct ip6_hdr),
2008 __FILE__, __LINE__));
2009 goto bad;
2010 }
2011
2012 /*
2013 * If there are extra headers between IPv6 and ICMPv6, strip
2014 * off that header first.
2015 */
2016#ifdef DIAGNOSTIC
2017 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN)
2018 panic("assumption failed in icmp6_reflect");
2019#endif
2020 if (off > sizeof(struct ip6_hdr)) {
2021 size_t l;
2022 struct ip6_hdr nip6;
2023
2024 l = off - sizeof(struct ip6_hdr);
2025 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6);
2026 m_adj(m, l);
2027 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
2028 if (m->m_len < l) {
2029 if ((m = m_pullup(m, l)) == NULL)
2030 return;
2031 }
2032 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6));
2033 } else /* off == sizeof(struct ip6_hdr) */ {
2034 size_t l;
2035 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
2036 if (m->m_len < l) {
2037 if ((m = m_pullup(m, l)) == NULL)
2038 return;
2039 }
2040 }
2041 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr);
2042 ip6 = mtod(m, struct ip6_hdr *);
2043 ip6->ip6_nxt = IPPROTO_ICMPV6;
2044 icmp6 = (struct icmp6_hdr *)(ip6 + 1);
2045 type = icmp6->icmp6_type; /* keep type for statistics */
2046 code = icmp6->icmp6_code; /* ditto. */
2047 hlim = 0;
2048 srcp = NULL;
2049
2050 /*
2051 * If the incoming packet was addressed directly to us (i.e. unicast),
2052 * use dst as the src for the reply.
2053 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible
2054 * (for example) when we encounter an error while forwarding procedure
2055 * destined to a duplicated address of ours.
2056 */
2057 if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
2058 ia = in6ifa_ifwithaddr(&ip6->ip6_dst, 0 /* XXX */, false);
2059 if (ia != NULL && !(ia->ia6_flags &
2060 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) {
2061 src6 = ia->ia_addr.sin6_addr;
2062 srcp = &src6;
2063
2064 if (m->m_pkthdr.rcvif != NULL) {
2065 /* XXX: This may not be the outgoing interface */
2066 hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim;
2067 } else
2068 hlim = V_ip6_defhlim;
2069 }
2070 }
2071
2072 if (srcp == NULL) {
2073 int error;
2074 struct in6_addr dst6;
2075 uint32_t scopeid;
2076
2077 /*
2078 * This case matches to multicasts, our anycast, or unicasts
2079 * that we do not own. Select a source address based on the
2080 * source address of the erroneous packet.
2081 */
2082 in6_splitscope(&ip6->ip6_src, &dst6, &scopeid);
2083 error = in6_selectsrc_addr(M_GETFIB(m), &dst6,
2084 scopeid, NULL, &src6, &hlim);
2085
2086 if (error) {
2087 char ip6buf[INET6_ADDRSTRLEN];
2088 nd6log((LOG_DEBUG,
2089 "icmp6_reflect: source can't be determined: "
2090 "dst=%s, error=%d\n",
2091 ip6_sprintf(ip6buf, &ip6->ip6_dst), error));
2092 goto bad;
2093 }
2094 srcp = &src6;
2095 }
2096 /*
2097 * ip6_input() drops a packet if its src is multicast.
2098 * So, the src is never multicast.
2099 */
2100 ip6->ip6_dst = ip6->ip6_src;
2101 ip6->ip6_src = *srcp;
2102 ip6->ip6_flow = 0;
2103 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
2104 ip6->ip6_vfc |= IPV6_VERSION;
2105 ip6->ip6_nxt = IPPROTO_ICMPV6;
2106 ip6->ip6_hlim = hlim;
2107
2108 icmp6->icmp6_cksum = 0;
2109 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6,
2110 sizeof(struct ip6_hdr), plen);
2111
2112 /*
2113 * XXX option handling
2114 */
2115
2116 m->m_flags &= ~(M_BCAST|M_MCAST);
2117 m->m_pkthdr.rcvif = NULL;
2118 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
2119 if (outif)
2120 icmp6_ifoutstat_inc(outif, type, code);
2121
2122 return;
2123
2124 bad:
2125 m_freem(m);
2126 return;
2127}
2128
2129void
2130icmp6_fasttimo(void)
2131{
2132
2133 mld_fasttimo();
2134}
2135
2136void
2137icmp6_slowtimo(void)
2138{
2139
2140 mld_slowtimo();
2141}
2142
2143static const char *
2144icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6,
2145 struct in6_addr *tgt6)
2146{
2147 static char buf[1024];
2148 char ip6bufs[INET6_ADDRSTRLEN];
2149 char ip6bufd[INET6_ADDRSTRLEN];
2150 char ip6buft[INET6_ADDRSTRLEN];
2151 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)",
2152 ip6_sprintf(ip6bufs, src6), ip6_sprintf(ip6bufd, dst6),
2153 ip6_sprintf(ip6buft, tgt6));
2154 return buf;
2155}
2156
2157void
2158icmp6_redirect_input(struct mbuf *m, int off)
2159{
2160 struct ifnet *ifp;
2161 struct ip6_hdr *ip6;
2162 struct nd_redirect *nd_rd;
2163 struct in6_addr src6, redtgt6, reddst6;
2164 union nd_opts ndopts;
2165 char ip6buf[INET6_ADDRSTRLEN];
2166 char *lladdr;
2167 int icmp6len, is_onlink, is_router, lladdrlen;
2168
2169 M_ASSERTPKTHDR(m);
2170 KASSERT(m->m_pkthdr.rcvif != NULL, ("%s: no rcvif", __func__));
2171
2172 /* XXX if we are router, we don't update route by icmp6 redirect */
2173 if (V_ip6_forwarding)
2174 goto freeit;
2175 if (!V_icmp6_rediraccept)
2176 goto freeit;
2177
2178 /* RFC 6980: Nodes MUST silently ignore fragments */
2179 if(m->m_flags & M_FRAGMENTED)
2180 goto freeit;
2181
2182 ip6 = mtod(m, struct ip6_hdr *);
2183 icmp6len = ntohs(ip6->ip6_plen);
2184 if (m->m_len < off + icmp6len) {
2185 m = m_pullup(m, off + icmp6len);
2186 if (m == NULL) {
2187 IP6STAT_INC(ip6s_exthdrtoolong);
2188 return;
2189 }
2190 }
2191 ip6 = mtod(m, struct ip6_hdr *);
2192 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off);
2193
2194 ifp = m->m_pkthdr.rcvif;
2195 redtgt6 = nd_rd->nd_rd_target;
2196 reddst6 = nd_rd->nd_rd_dst;
2197
2198 if (in6_setscope(&redtgt6, ifp, NULL) ||
2199 in6_setscope(&reddst6, ifp, NULL)) {
2200 goto freeit;
2201 }
2202
2203 /* validation */
2204 src6 = ip6->ip6_src;
2205 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) {
2206 nd6log((LOG_ERR,
2207 "ICMP6 redirect sent from %s rejected; "
2208 "must be from linklocal\n",
2209 ip6_sprintf(ip6buf, &src6)));
2210 goto bad;
2211 }
2212 if (__predict_false(ip6->ip6_hlim != 255)) {
2213 ICMP6STAT_INC(icp6s_invlhlim);
2214 nd6log((LOG_ERR,
2215 "ICMP6 redirect sent from %s rejected; "
2216 "hlim=%d (must be 255)\n",
2217 ip6_sprintf(ip6buf, &src6), ip6->ip6_hlim));
2218 goto bad;
2219 }
2220 {
2221 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */
2222 struct nhop_object *nh;
2223 struct in6_addr kdst;
2224 uint32_t scopeid;
2225
2226 in6_splitscope(&reddst6, &kdst, &scopeid);
2227 NET_EPOCH_ASSERT();
2228 nh = fib6_lookup(ifp->if_fib, &kdst, scopeid, 0, 0);
2229 if (nh != NULL) {
2230 struct in6_addr nh_addr;
2231 nh_addr = ifatoia6(nh->nh_ifa)->ia_addr.sin6_addr;
2232 if ((nh->nh_flags & NHF_GATEWAY) == 0) {
2233 nd6log((LOG_ERR,
2234 "ICMP6 redirect rejected; no route "
2235 "with inet6 gateway found for redirect dst: %s\n",
2236 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2237 goto bad;
2238 }
2239
2240 /*
2241 * Embed scope zone id into next hop address.
2242 */
2243 nh_addr = nh->gw6_sa.sin6_addr;
2244
2245 if (IN6_ARE_ADDR_EQUAL(&src6, &nh_addr) == 0) {
2246 nd6log((LOG_ERR,
2247 "ICMP6 redirect rejected; "
2248 "not equal to gw-for-src=%s (must be same): "
2249 "%s\n",
2250 ip6_sprintf(ip6buf, &nh_addr),
2251 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2252 goto bad;
2253 }
2254 } else {
2255 nd6log((LOG_ERR,
2256 "ICMP6 redirect rejected; "
2257 "no route found for redirect dst: %s\n",
2258 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2259 goto bad;
2260 }
2261 }
2262 if (IN6_IS_ADDR_MULTICAST(&reddst6)) {
2263 nd6log((LOG_ERR,
2264 "ICMP6 redirect rejected; "
2265 "redirect dst must be unicast: %s\n",
2266 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2267 goto bad;
2268 }
2269
2270 is_router = is_onlink = 0;
2271 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
2272 is_router = 1; /* router case */
2273 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0)
2274 is_onlink = 1; /* on-link destination case */
2275 if (!is_router && !is_onlink) {
2276 nd6log((LOG_ERR,
2277 "ICMP6 redirect rejected; "
2278 "neither router case nor onlink case: %s\n",
2279 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2280 goto bad;
2281 }
2282
2283 icmp6len -= sizeof(*nd_rd);
2284 nd6_option_init(nd_rd + 1, icmp6len, &ndopts);
2285 if (nd6_options(&ndopts) < 0) {
2286 nd6log((LOG_INFO, "%s: invalid ND option, rejected: %s\n",
2287 __func__, icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2288 /* nd6_options have incremented stats */
2289 goto freeit;
2290 }
2291
2292 lladdr = NULL;
2293 lladdrlen = 0;
2294 if (ndopts.nd_opts_tgt_lladdr) {
2295 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
2296 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
2297 }
2298
2299 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
2300 nd6log((LOG_INFO, "%s: lladdrlen mismatch for %s "
2301 "(if %d, icmp6 packet %d): %s\n",
2302 __func__, ip6_sprintf(ip6buf, &redtgt6),
2303 ifp->if_addrlen, lladdrlen - 2,
2304 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
2305 goto bad;
2306 }
2307
2308 /* Validation passed. */
2309
2310 /* RFC 2461 8.3 */
2311 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT,
2312 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER);
2313
2314 /*
2315 * Install a gateway route in the better-router case or an interface
2316 * route in the on-link-destination case.
2317 */
2318 {
2319 struct sockaddr_in6 sdst;
2320 struct sockaddr_in6 sgw;
2321 struct sockaddr_in6 ssrc;
2322 struct sockaddr *gw;
2323 int rt_flags;
2324 u_int fibnum;
2325
2326 bzero(&sdst, sizeof(sdst));
2327 bzero(&ssrc, sizeof(ssrc));
2328 sdst.sin6_family = ssrc.sin6_family = AF_INET6;
2329 sdst.sin6_len = ssrc.sin6_len = sizeof(struct sockaddr_in6);
2330 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
2331 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr));
2332 rt_flags = 0;
2333 if (is_router) {
2334 bzero(&sgw, sizeof(sgw));
2335 sgw.sin6_family = AF_INET6;
2336 sgw.sin6_len = sizeof(struct sockaddr_in6);
2337 bcopy(&redtgt6, &sgw.sin6_addr,
2338 sizeof(struct in6_addr));
2339 gw = (struct sockaddr *)&sgw;
2340 rt_flags |= RTF_GATEWAY;
2341 } else
2342 gw = ifp->if_addr->ifa_addr;
2343 for (fibnum = 0; fibnum < rt_numfibs; fibnum++)
2344 rib_add_redirect(fibnum, (struct sockaddr *)&sdst, gw,
2345 (struct sockaddr *)&ssrc, ifp, rt_flags,
2346 V_icmp6_redirtimeout);
2347 }
2348 /* finally update cached route in each socket via pfctlinput */
2349 {
2350 struct sockaddr_in6 sdst;
2351
2352 bzero(&sdst, sizeof(sdst));
2353 sdst.sin6_family = AF_INET6;
2354 sdst.sin6_len = sizeof(struct sockaddr_in6);
2355 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
2356 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst);
2357 }
2358
2359 freeit:
2360 m_freem(m);
2361 return;
2362
2363 bad:
2364 ICMP6STAT_INC(icp6s_badredirect);
2365 m_freem(m);
2366}
2367
2368void
2369icmp6_redirect_output(struct mbuf *m0, struct nhop_object *nh)
2370{
2371 struct ifnet *ifp; /* my outgoing interface */
2372 struct in6_addr *ifp_ll6;
2373 struct in6_addr *router_ll6;
2374 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */
2375 struct mbuf *m = NULL; /* newly allocated one */
2376 struct m_tag *mtag;
2377 struct ip6_hdr *ip6; /* m as struct ip6_hdr */
2378 struct nd_redirect *nd_rd;
2379 struct llentry *ln = NULL;
2380 size_t maxlen;
2381 u_char *p;
2382 struct ifnet *outif = NULL;
2383 struct sockaddr_in6 src_sa;
2384
2385 icmp6_errcount(ND_REDIRECT, 0);
2386
2387 /* if we are not router, we don't send icmp6 redirect */
2388 if (!V_ip6_forwarding)
2389 goto fail;
2390
2391 /* sanity check */
2392 if (!m0 || !nh || !(NH_IS_VALID(nh)) || !(ifp = nh->nh_ifp))
2393 goto fail;
2394
2395 /*
2396 * Address check:
2397 * the source address must identify a neighbor, and
2398 * the destination address must not be a multicast address
2399 * [RFC 2461, sec 8.2]
2400 */
2401 sip6 = mtod(m0, struct ip6_hdr *);
2402 bzero(&src_sa, sizeof(src_sa));
2403 src_sa.sin6_family = AF_INET6;
2404 src_sa.sin6_len = sizeof(src_sa);
2405 src_sa.sin6_addr = sip6->ip6_src;
2406 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0)
2407 goto fail;
2408 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst))
2409 goto fail; /* what should we do here? */
2410
2411 /* rate limit */
2412 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0))
2413 goto fail;
2414
2415 /*
2416 * Since we are going to append up to 1280 bytes (= IPV6_MMTU),
2417 * we almost always ask for an mbuf cluster for simplicity.
2418 * (MHLEN < IPV6_MMTU is almost always true)
2419 */
2420#if IPV6_MMTU >= MCLBYTES
2421# error assumption failed about IPV6_MMTU and MCLBYTES
2422#endif
2423 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
2424 if (m == NULL)
2425 goto fail;
2426 M_SETFIB(m, M_GETFIB(m0));
2427 maxlen = M_TRAILINGSPACE(m);
2428 maxlen = min(IPV6_MMTU, maxlen);
2429 /* just for safety */
2430 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) +
2431 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) {
2432 goto fail;
2433 }
2434
2435 {
2436 /* get ip6 linklocal address for ifp(my outgoing interface). */
2437 struct in6_ifaddr *ia;
2438 if ((ia = in6ifa_ifpforlinklocal(ifp,
2439 IN6_IFF_NOTREADY|
2440 IN6_IFF_ANYCAST)) == NULL)
2441 goto fail;
2442 ifp_ll6 = &ia->ia_addr.sin6_addr;
2443 /* XXXRW: reference released prematurely. */
2444 ifa_free(&ia->ia_ifa);
2445 }
2446
2447 /* get ip6 linklocal address for the router. */
2448 if (nh->nh_flags & NHF_GATEWAY) {
2449 struct sockaddr_in6 *sin6;
2450 sin6 = &nh->gw6_sa;
2451 router_ll6 = &sin6->sin6_addr;
2452 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6))
2453 router_ll6 = (struct in6_addr *)NULL;
2454 } else
2455 router_ll6 = (struct in6_addr *)NULL;
2456
2457 /* ip6 */
2458 ip6 = mtod(m, struct ip6_hdr *);
2459 ip6->ip6_flow = 0;
2460 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
2461 ip6->ip6_vfc |= IPV6_VERSION;
2462 /* ip6->ip6_plen will be set later */
2463 ip6->ip6_nxt = IPPROTO_ICMPV6;
2464 ip6->ip6_hlim = 255;
2465 /* ip6->ip6_src must be linklocal addr for my outgoing if. */
2466 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr));
2467 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr));
2468
2469 /* ND Redirect */
2470 nd_rd = (struct nd_redirect *)(ip6 + 1);
2471 nd_rd->nd_rd_type = ND_REDIRECT;
2472 nd_rd->nd_rd_code = 0;
2473 nd_rd->nd_rd_reserved = 0;
2474 if (nh->nh_flags & NHF_GATEWAY) {
2475 /*
2476 * nd_rd->nd_rd_target must be a link-local address in
2477 * better router cases.
2478 */
2479 if (!router_ll6)
2480 goto fail;
2481 bcopy(router_ll6, &nd_rd->nd_rd_target,
2482 sizeof(nd_rd->nd_rd_target));
2483 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2484 sizeof(nd_rd->nd_rd_dst));
2485 } else {
2486 /* make sure redtgt == reddst */
2487 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target,
2488 sizeof(nd_rd->nd_rd_target));
2489 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2490 sizeof(nd_rd->nd_rd_dst));
2491 }
2492
2493 p = (u_char *)(nd_rd + 1);
2494
2495 if (!router_ll6)
2496 goto nolladdropt;
2497
2498 {
2499 /* target lladdr option */
2500 int len;
2501 struct nd_opt_hdr *nd_opt;
2502 char *lladdr;
2503
2504 ln = nd6_lookup(router_ll6, LLE_SF(AF_INET6, 0), ifp);
2505 if (ln == NULL)
2506 goto nolladdropt;
2507
2508 len = sizeof(*nd_opt) + ifp->if_addrlen;
2509 len = (len + 7) & ~7; /* round by 8 */
2510 /* safety check */
2511 if (len + (p - (u_char *)ip6) > maxlen)
2512 goto nolladdropt;
2513
2514 if (ln->la_flags & LLE_VALID) {
2515 nd_opt = (struct nd_opt_hdr *)p;
2516 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
2517 nd_opt->nd_opt_len = len >> 3;
2518 lladdr = (char *)(nd_opt + 1);
2519 bcopy(ln->ll_addr, lladdr, ifp->if_addrlen);
2520 p += len;
2521 }
2522 }
2523nolladdropt:
2524 if (ln != NULL)
2525 LLE_RUNLOCK(ln);
2526
2527 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2528
2529 /* just to be safe */
2530#ifdef M_DECRYPTED /*not openbsd*/
2531 if (m0->m_flags & M_DECRYPTED)
2532 goto noredhdropt;
2533#endif
2534 if (p - (u_char *)ip6 > maxlen)
2535 goto noredhdropt;
2536
2537 {
2538 /* redirected header option */
2539 int len;
2540 struct nd_opt_rd_hdr *nd_opt_rh;
2541
2542 /*
2543 * compute the maximum size for icmp6 redirect header option.
2544 * XXX room for auth header?
2545 */
2546 len = maxlen - (p - (u_char *)ip6);
2547 len &= ~7;
2548
2549 /* This is just for simplicity. */
2550 if (m0->m_pkthdr.len != m0->m_len) {
2551 if (m0->m_next) {
2552 m_freem(m0->m_next);
2553 m0->m_next = NULL;
2554 }
2555 m0->m_pkthdr.len = m0->m_len;
2556 }
2557
2558 /*
2559 * Redirected header option spec (RFC2461 4.6.3) talks nothing
2560 * about padding/truncate rule for the original IP packet.
2561 * From the discussion on IPv6imp in Feb 1999,
2562 * the consensus was:
2563 * - "attach as much as possible" is the goal
2564 * - pad if not aligned (original size can be guessed by
2565 * original ip6 header)
2566 * Following code adds the padding if it is simple enough,
2567 * and truncates if not.
2568 */
2569 if (m0->m_next || m0->m_pkthdr.len != m0->m_len)
2570 panic("assumption failed in %s:%d", __FILE__,
2571 __LINE__);
2572
2573 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) {
2574 /* not enough room, truncate */
2575 m0->m_pkthdr.len = m0->m_len = len -
2576 sizeof(*nd_opt_rh);
2577 } else {
2578 /* enough room, pad or truncate */
2579 size_t extra;
2580
2581 extra = m0->m_pkthdr.len % 8;
2582 if (extra) {
2583 /* pad if easy enough, truncate if not */
2584 if (8 - extra <= M_TRAILINGSPACE(m0)) {
2585 /* pad */
2586 m0->m_len += (8 - extra);
2587 m0->m_pkthdr.len += (8 - extra);
2588 } else {
2589 /* truncate */
2590 m0->m_pkthdr.len -= extra;
2591 m0->m_len -= extra;
2592 }
2593 }
2594 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh);
2595 m0->m_pkthdr.len = m0->m_len = len -
2596 sizeof(*nd_opt_rh);
2597 }
2598
2599 nd_opt_rh = (struct nd_opt_rd_hdr *)p;
2600 bzero(nd_opt_rh, sizeof(*nd_opt_rh));
2601 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER;
2602 nd_opt_rh->nd_opt_rh_len = len >> 3;
2603 p += sizeof(*nd_opt_rh);
2604 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2605
2606 /* connect m0 to m */
2607 m_tag_delete_chain(m0, NULL);
2608 m0->m_flags &= ~M_PKTHDR;
2609 m->m_next = m0;
2610 m->m_pkthdr.len = m->m_len + m0->m_len;
2611 m0 = NULL;
2612 }
2613noredhdropt:;
2614 if (m0) {
2615 m_freem(m0);
2616 m0 = NULL;
2617 }
2618
2619 /* XXX: clear embedded link IDs in the inner header */
2620 in6_clearscope(&sip6->ip6_src);
2621 in6_clearscope(&sip6->ip6_dst);
2622 in6_clearscope(&nd_rd->nd_rd_target);
2623 in6_clearscope(&nd_rd->nd_rd_dst);
2624
2625 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
2626
2627 nd_rd->nd_rd_cksum = 0;
2628 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6,
2629 sizeof(*ip6), ntohs(ip6->ip6_plen));
2630
2631 if (send_sendso_input_hook != NULL) {
2632 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, sizeof(unsigned short),
2633 M_NOWAIT);
2634 if (mtag == NULL)
2635 goto fail;
2636 *(unsigned short *)(mtag + 1) = nd_rd->nd_rd_type;
2637 m_tag_prepend(m, mtag);
2638 }
2639
2640 /* send the packet to outside... */
2641 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
2642 if (outif) {
2643 icmp6_ifstat_inc(outif, ifs6_out_msg);
2644 icmp6_ifstat_inc(outif, ifs6_out_redirect);
2645 }
2646 ICMP6STAT_INC(icp6s_outhist[ND_REDIRECT]);
2647
2648 return;
2649
2650fail:
2651 if (m)
2652 m_freem(m);
2653 if (m0)
2654 m_freem(m0);
2655}
2656
2657/*
2658 * ICMPv6 socket option processing.
2659 */
2660int
2661icmp6_ctloutput(struct socket *so, struct sockopt *sopt)
2662{
2663 int error = 0;
2664 int optlen;
2665 struct inpcb *inp = sotoinpcb(so);
2666 int level, op, optname;
2667
2668 if (sopt) {
2669 level = sopt->sopt_level;
2670 op = sopt->sopt_dir;
2671 optname = sopt->sopt_name;
2672 optlen = sopt->sopt_valsize;
2673 } else
2674 level = op = optname = optlen = 0;
2675
2676 if (level != IPPROTO_ICMPV6) {
2677 return EINVAL;
2678 }
2679
2680 switch (op) {
2681 case PRCO_SETOPT:
2682 switch (optname) {
2683 case ICMP6_FILTER:
2684 {
2685 struct icmp6_filter ic6f;
2686
2687 if (optlen != sizeof(ic6f)) {
2688 error = EMSGSIZE;
2689 break;
2690 }
2691 error = sooptcopyin(sopt, &ic6f, optlen, optlen);
2692 if (error == 0) {
2693 INP_WLOCK(inp);
2694 *inp->in6p_icmp6filt = ic6f;
2695 INP_WUNLOCK(inp);
2696 }
2697 break;
2698 }
2699
2700 default:
2701 error = ENOPROTOOPT;
2702 break;
2703 }
2704 break;
2705
2706 case PRCO_GETOPT:
2707 switch (optname) {
2708 case ICMP6_FILTER:
2709 {
2710 struct icmp6_filter ic6f;
2711
2712 INP_RLOCK(inp);
2713 ic6f = *inp->in6p_icmp6filt;
2714 INP_RUNLOCK(inp);
2715 error = sooptcopyout(sopt, &ic6f, sizeof(ic6f));
2716 break;
2717 }
2718
2719 default:
2720 error = ENOPROTOOPT;
2721 break;
2722 }
2723 break;
2724 }
2725
2726 return (error);
2727}
2728
2729/*
2730 * Perform rate limit check.
2731 * Returns 0 if it is okay to send the icmp6 packet.
2732 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate
2733 * limitation.
2734 *
2735 * XXX per-destination/type check necessary?
2736 *
2737 * dst - not used at this moment
2738 * type - not used at this moment
2739 * code - not used at this moment
2740 */
2741static int
2742icmp6_ratelimit(const struct in6_addr *dst, const int type,
2743 const int code)
2744{
2745 int ret;
2746
2747 ret = 0; /* okay to send */
2748
2749 /* PPS limit */
2750 if (!ppsratecheck(&V_icmp6errppslim_last, &V_icmp6errpps_count,
2751 V_icmp6errppslim)) {
2752 /* The packet is subject to rate limit */
2753 ret++;
2754 }
2755
2756 return ret;
2757}
V_icmp6errppslim
#define V_icmp6errppslim
Definition: icmp6.c:133
ni6_dnsmatch
static int ni6_dnsmatch(const char *, int, const char *, int)
Definition: icmp6.c:1592
icmp6_errcount
static void icmp6_errcount(int, int)
Definition: icmp6.c:168
icmp6_slowtimo
void icmp6_slowtimo(void)
Definition: icmp6.c:2137
icmp6_notify_error
static int icmp6_notify_error(struct mbuf **, int, int, int)
Definition: icmp6.c:896
icmp6_redirect_output
void icmp6_redirect_output(struct mbuf *m0, struct nhop_object *nh)
Definition: icmp6.c:2369
ni6_addrs
static int ni6_addrs(struct icmp6_nodeinfo *, struct mbuf *, struct ifnet **, struct in6_addr *)
Definition: icmp6.c:1652
icmp6_fasttimo
void icmp6_fasttimo(void)
Definition: icmp6.c:2130
icmp6_rip6_input
static int icmp6_rip6_input(struct mbuf **, int)
Definition: icmp6.c:1898
icmp6_ratelimit
static int icmp6_ratelimit(const struct in6_addr *, const int, const int)
Definition: icmp6.c:2742
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void icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated)
Definition: icmp6.c:1107
__FBSDID
__FBSDID("$FreeBSD$")
icmp6_rip6_match
static bool icmp6_rip6_match(const struct inpcb *inp, void *v)
Definition: icmp6.c:1877
V_icmp6_nodeinfo
#define V_icmp6_nodeinfo
Definition: icmp6.c:136
ni6_store_addrs
static int ni6_store_addrs(struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, struct ifnet *, int)
Definition: icmp6.c:1742
V_icmp6errppslim_last
#define V_icmp6errppslim_last
Definition: icmp6.c:135
VNET_PCPUSTAT_DEFINE
VNET_PCPUSTAT_DEFINE(struct icmp6stat, icmp6stat)
icmp6_error2
void icmp6_error2(struct mbuf *m, int type, int code, int param, struct ifnet *ifp)
Definition: icmp6.c:228
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struct domain inet6domain
Definition: in6_proto.c:334
icmp6_reflect
static void icmp6_reflect(struct mbuf *, size_t)
Definition: icmp6.c:1993
icmp6_error
void icmp6_error(struct mbuf *m, int type, int code, int param)
Definition: icmp6.c:257
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int icmp6_input(struct mbuf **mp, int *offp, int proto)
Definition: icmp6.c:398
ni6_nametodns
static struct mbuf * ni6_nametodns(const char *, int, int)
Definition: icmp6.c:1498
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int icmp6_ctloutput(struct socket *so, struct sockopt *sopt)
Definition: icmp6.c:2661
VNET_PCPUSTAT_SYSINIT
VNET_PCPUSTAT_SYSINIT(icmp6stat)
V_ripcbinfo
#define V_ripcbinfo
Definition: icmp6.c:132
ni6_input
static struct mbuf * ni6_input(struct mbuf *, int, struct prison *)
Definition: icmp6.c:1172
V_icmp6errpps_count
#define V_icmp6errpps_count
Definition: icmp6.c:134
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Definition: icmp6.c:2158
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static const char * icmp6_redirect_diag(struct in6_addr *, struct in6_addr *, struct in6_addr *)
Definition: icmp6.c:2144
VNET_DECLARE
VNET_DECLARE(struct inpcbinfo, ripcbinfo)
VNET_DEFINE_STATIC
VNET_DEFINE_STATIC(int, icmp6errpps_count)=0
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Definition: icmp6.c:161
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Definition: in6.c:1534
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Definition: in6.c:1637
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struct in6_ifaddr * in6ifa_ifwithaddr(const struct in6_addr *addr, uint32_t zoneid, bool referenced)
Definition: in6.c:1560
IPV6_RTHDR_TYPE_0
#define IPV6_RTHDR_TYPE_0
Definition: in6.h:517
M_FRAGMENTED
#define M_FRAGMENTED
Definition: in6.h:660
IPV6_ADDR_SCOPE_GLOBAL
#define IPV6_ADDR_SCOPE_GLOBAL
Definition: in6.h:282
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Definition: in6.h:420
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Definition: scope6.c:235
IN6_IS_ADDR_LINKLOCAL
#define IN6_IS_ADDR_LINKLOCAL(a)
Definition: in6.h:296
IN6_IS_ADDR_MC_LINKLOCAL
#define IN6_IS_ADDR_MC_LINKLOCAL(a)
Definition: in6.h:322
IN6_IS_ADDR_UNSPECIFIED
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Definition: in6.h:239
IN6_IS_ADDR_LOOPBACK
#define IN6_IS_ADDR_LOOPBACK(a)
Definition: in6.h:248
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Definition: ip6_input.c:129
M_RTALERT_MLD
#define M_RTALERT_MLD
Definition: in6.h:659
M_DECRYPTED
#define M_DECRYPTED
Definition: in6.h:656
IN6_ARE_ADDR_EQUAL
#define IN6_ARE_ADDR_EQUAL(a, b)
Definition: in6.h:227
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int in6_cksum(struct mbuf *, u_int8_t, u_int32_t, u_int32_t)
Definition: in6_cksum.c:364
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#define ifatoia6(ifa)
Definition: in6.h:691
IN6_IS_ADDR_MULTICAST
#define IN6_IS_ADDR_MULTICAST(a)
Definition: in6.h:304
IPV6_ADDR_SCOPE_LINKLOCAL
#define IPV6_ADDR_SCOPE_LINKLOCAL
Definition: in6.h:279
INET6_ADDRSTRLEN
#define INET6_ADDRSTRLEN
Definition: in6.h:112
IPV6_ADDR_SCOPE_SITELOCAL
#define IPV6_ADDR_SCOPE_SITELOCAL
Definition: in6.h:280
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fib6_lookup
struct nhop_object * fib6_lookup(uint32_t fibnum, const struct in6_addr *dst6, uint32_t scopeid, uint32_t flags, uint32_t flowid)
in6_ifattach.h
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struct protosw inet6sw[]
Definition: in6_proto.c:143
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int in6_selectsrc_addr(uint32_t fibnum, const struct in6_addr *dst, uint32_t scopeid, struct ifnet *ifp, struct in6_addr *srcp, int *hlim)
Definition: in6_src.c:586
IN6_IFF_DEPRECATED
#define IN6_IFF_DEPRECATED
Definition: in6_var.h:497
IN6_IFF_ANYCAST
#define IN6_IFF_ANYCAST
Definition: in6_var.h:493
IN6_IFF_TEMPORARY
#define IN6_IFF_TEMPORARY
Definition: in6_var.h:500
IN6_IFF_NOTREADY
#define IN6_IFF_NOTREADY
Definition: in6_var.h:504
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static __inline struct in6_multi * in6m_lookup(struct ifnet *ifp, const struct in6_addr *mcaddr)
Definition: in6_var.h:812
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#define in6_ifstat_inc(ifp, tag)
Definition: in6_var.h:544
ip6_savecontrol
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Definition: ip6_input.c:1389
ip6_lasthdr
int ip6_lasthdr(const struct mbuf *m, int off, int proto, int *nxtp)
Definition: ip6_input.c:1717
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static struct sockaddr_in6 sin6
Definition: ip6_mroute.c:672
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int ip6_output(struct mbuf *m0, struct ip6_pktopts *opt, struct route_in6 *ro, int flags, struct ip6_moptions *im6o, struct ifnet **ifpp, struct inpcb *inp)
Definition: ip6_output.c:409
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IP6STAT_INC
#define IP6STAT_INC(name)
Definition: ip6_var.h:256
V_ip6_forwarding
#define V_ip6_forwarding
Definition: ip6_var.h:282
IP6STAT_DEC
#define IP6STAT_DEC(name)
Definition: ip6_var.h:257
V_ip6_defhlim
#define V_ip6_defhlim
Definition: ip6_var.h:280
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Definition: mld6.c:1739
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Definition: mld6.c:1248
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void mld_fasttimo(void)
Definition: mld6.c:1326
mld6_var.h
nd6_is_addr_neighbor
int nd6_is_addr_neighbor(const struct sockaddr_in6 *addr, struct ifnet *ifp)
Definition: nd6.c:1368
nd6_lookup
struct llentry * nd6_lookup(const struct in6_addr *addr6, int flags, struct ifnet *ifp)
Definition: nd6.c:1192
nd6_cache_lladdr
void nd6_cache_lladdr(struct ifnet *ifp, struct in6_addr *from, char *lladdr, int lladdrlen, int type, int code)
Definition: nd6.c:1989
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int nd6_options(union nd_opts *ndopts)
Definition: nd6.c:440
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int(* send_sendso_input_hook)(struct mbuf *, struct ifnet *, int, int)
Definition: nd6.c:130
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void nd6_option_init(void *opt, int icmp6len, union nd_opts *ndopts)
Definition: nd6.c:372
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void nd6_ra_input(struct mbuf *, int, int)
Definition: nd6_rtr.c:353
nd6log
#define nd6log(x)
Definition: nd6.h:303
ND_IFINFO
#define ND_IFINFO(ifp)
Definition: nd6.h:99
nd6_rs_input
void nd6_rs_input(struct mbuf *, int, int)
Definition: nd6_rtr.c:153
ND6_INFINITE_LIFETIME
#define ND6_INFINITE_LIFETIME
Definition: nd6.h:177
nd6_ns_input
void nd6_ns_input(struct mbuf *, int, int)
Definition: nd6_nbr.c:118
nd6_na_input
void nd6_na_input(struct mbuf *, int, int)
Definition: nd6_nbr.c:627
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int in6_setscope(struct in6_addr *in6, struct ifnet *ifp, u_int32_t *ret_id)
Definition: scope6.c:406
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void in6_splitscope(const struct in6_addr *src, struct in6_addr *dst, uint32_t *scopeid)
Definition: scope6.c:534
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int in6_clearscope(struct in6_addr *in6)
Definition: scope6.c:455
sa6_recoverscope
int sa6_recoverscope(struct sockaddr_in6 *sin6)
Definition: scope6.c:361
scope6_var.h
SND_IN
#define SND_IN
Definition: send.h:35
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Definition: in6.h:97
in6_addrlifetime::ia6t_expire
time_t ia6t_expire
Definition: in6_var.h:93
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Definition: in6_var.h:121
in6_ifaddr::ia6_flags
int ia6_flags
Definition: in6_var.h:131
in6_ifaddr::ia_addr
struct sockaddr_in6 ia_addr
Definition: in6_var.h:125
in6_ifaddr::ia_ifa
struct ifaddr ia_ifa
Definition: in6_var.h:122
in6_ifaddr::ia6_lifetime
struct in6_addrlifetime ia6_lifetime
Definition: in6_var.h:133
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Definition: in6_var.h:688
ip6ctlparam::ip6c_ip6
struct ip6_hdr * ip6c_ip6
Definition: ip6protosw.h:106
ip6ctlparam::ip6c_nxt
u_int8_t ip6c_nxt
Definition: ip6protosw.h:112
ip6ctlparam::ip6c_icmp6
struct icmp6_hdr * ip6c_icmp6
Definition: ip6protosw.h:105
ip6ctlparam::ip6c_m
struct mbuf * ip6c_m
Definition: ip6protosw.h:104
ip6ctlparam::ip6c_finaldst
struct in6_addr * ip6c_finaldst
Definition: ip6protosw.h:110
ip6ctlparam::ip6c_src
struct sockaddr_in6 * ip6c_src
Definition: ip6protosw.h:108
ip6ctlparam::ip6c_cmdarg
void * ip6c_cmdarg
Definition: ip6protosw.h:111
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Definition: in6.h:125
sockaddr_in6::sin6_len
uint8_t sin6_len
Definition: in6.h:126
sockaddr_in6::sin6_addr
struct in6_addr sin6_addr
Definition: in6.h:130
sockaddr_in6::sin6_flowinfo
uint32_t sin6_flowinfo
Definition: in6.h:129
sockaddr_in6::sin6_family
sa_family_t sin6_family
Definition: in6.h:127
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Definition: nd6.h:317