ip6_input.c revision 1.84 1 /* $NetBSD: ip6_input.c,v 1.84 2006/04/15 00:13:23 christos Exp $ */
2 /* $KAME: ip6_input.c,v 1.188 2001/03/29 05:34:31 itojun Exp $ */
3
4 /*
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 /*
34 * Copyright (c) 1982, 1986, 1988, 1993
35 * The Regents of the University of California. All rights reserved.
36 *
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
39 * are met:
40 * 1. Redistributions of source code must retain the above copyright
41 * notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above copyright
43 * notice, this list of conditions and the following disclaimer in the
44 * documentation and/or other materials provided with the distribution.
45 * 3. Neither the name of the University nor the names of its contributors
46 * may be used to endorse or promote products derived from this software
47 * without specific prior written permission.
48 *
49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59 * SUCH DAMAGE.
60 *
61 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94
62 */
63
64 #include <sys/cdefs.h>
65 __KERNEL_RCSID(0, "$NetBSD: ip6_input.c,v 1.84 2006/04/15 00:13:23 christos Exp $");
66
67 #include "opt_inet.h"
68 #include "opt_ipsec.h"
69 #include "opt_pfil_hooks.h"
70
71 #include <sys/param.h>
72 #include <sys/systm.h>
73 #include <sys/malloc.h>
74 #include <sys/mbuf.h>
75 #include <sys/domain.h>
76 #include <sys/protosw.h>
77 #include <sys/socket.h>
78 #include <sys/socketvar.h>
79 #include <sys/errno.h>
80 #include <sys/time.h>
81 #include <sys/kernel.h>
82 #include <sys/syslog.h>
83 #include <sys/proc.h>
84 #include <sys/sysctl.h>
85
86 #include <net/if.h>
87 #include <net/if_types.h>
88 #include <net/if_dl.h>
89 #include <net/route.h>
90 #include <net/netisr.h>
91 #ifdef PFIL_HOOKS
92 #include <net/pfil.h>
93 #endif
94
95 #include <netinet/in.h>
96 #include <netinet/in_systm.h>
97 #ifdef INET
98 #include <netinet/ip.h>
99 #include <netinet/ip_icmp.h>
100 #endif /* INET */
101 #include <netinet/ip6.h>
102 #include <netinet6/in6_var.h>
103 #include <netinet6/ip6_var.h>
104 #include <netinet6/in6_pcb.h>
105 #include <netinet/icmp6.h>
106 #include <netinet6/scope6_var.h>
107 #include <netinet6/in6_ifattach.h>
108 #include <netinet6/nd6.h>
109
110 #ifdef IPSEC
111 #include <netinet6/ipsec.h>
112 #endif
113
114 #include <netinet6/ip6protosw.h>
115
116 #include "faith.h"
117 #include "gif.h"
118
119 #if NGIF > 0
120 #include <netinet6/in6_gif.h>
121 #endif
122
123 #include <net/net_osdep.h>
124
125 extern struct domain inet6domain;
126
127 u_char ip6_protox[IPPROTO_MAX];
128 static int ip6qmaxlen = IFQ_MAXLEN;
129 struct in6_ifaddr *in6_ifaddr;
130 struct ifqueue ip6intrq;
131
132 extern struct callout in6_tmpaddrtimer_ch;
133
134 int ip6_forward_srcrt; /* XXX */
135 int ip6_sourcecheck; /* XXX */
136 int ip6_sourcecheck_interval; /* XXX */
137
138 #ifdef PFIL_HOOKS
139 struct pfil_head inet6_pfil_hook;
140 #endif
141
142 struct ip6stat ip6stat;
143
144 static void ip6_init2 __P((void *));
145 static struct m_tag *ip6_setdstifaddr __P((struct mbuf *, struct in6_ifaddr *));
146
147 static int ip6_hopopts_input __P((u_int32_t *, u_int32_t *, struct mbuf **, int *));
148 static struct mbuf *ip6_pullexthdr __P((struct mbuf *, size_t, int));
149
150 /*
151 * IP6 initialization: fill in IP6 protocol switch table.
152 * All protocols not implemented in kernel go to raw IP6 protocol handler.
153 */
154 void
155 ip6_init()
156 {
157 const struct ip6protosw *pr;
158 int i;
159
160 pr = (const struct ip6protosw *)pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW);
161 if (pr == 0)
162 panic("ip6_init");
163 for (i = 0; i < IPPROTO_MAX; i++)
164 ip6_protox[i] = pr - inet6sw;
165 for (pr = (const struct ip6protosw *)inet6domain.dom_protosw;
166 pr < (const struct ip6protosw *)inet6domain.dom_protoswNPROTOSW; pr++)
167 if (pr->pr_domain->dom_family == PF_INET6 &&
168 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW)
169 ip6_protox[pr->pr_protocol] = pr - inet6sw;
170 ip6intrq.ifq_maxlen = ip6qmaxlen;
171 scope6_init();
172 addrsel_policy_init();
173 nd6_init();
174 frag6_init();
175 ip6_desync_factor = arc4random() % MAX_TEMP_DESYNC_FACTOR;
176
177 ip6_init2((void *)0);
178
179 #ifdef PFIL_HOOKS
180 /* Register our Packet Filter hook. */
181 inet6_pfil_hook.ph_type = PFIL_TYPE_AF;
182 inet6_pfil_hook.ph_af = AF_INET6;
183 i = pfil_head_register(&inet6_pfil_hook);
184 if (i != 0)
185 printf("ip6_init: WARNING: unable to register pfil hook, "
186 "error %d\n", i);
187 #endif /* PFIL_HOOKS */
188 }
189
190 static void
191 ip6_init2(dummy)
192 void *dummy;
193 {
194
195 /* nd6_timer_init */
196 callout_init(&nd6_timer_ch);
197 callout_reset(&nd6_timer_ch, hz, nd6_timer, NULL);
198
199 /* timer for regeneranation of temporary addresses randomize ID */
200 callout_init(&in6_tmpaddrtimer_ch);
201 callout_reset(&in6_tmpaddrtimer_ch,
202 (ip6_temp_preferred_lifetime - ip6_desync_factor -
203 ip6_temp_regen_advance) * hz,
204 in6_tmpaddrtimer, NULL);
205 }
206
207 /*
208 * IP6 input interrupt handling. Just pass the packet to ip6_input.
209 */
210 void
211 ip6intr()
212 {
213 int s;
214 struct mbuf *m;
215
216 for (;;) {
217 s = splnet();
218 IF_DEQUEUE(&ip6intrq, m);
219 splx(s);
220 if (m == 0)
221 return;
222 /* drop the packet if IPv6 operation is disabled on the IF */
223 if ((ND_IFINFO(m->m_pkthdr.rcvif)->flags & ND6_IFF_IFDISABLED)) {
224 m_freem(m);
225 return;
226 }
227 ip6_input(m);
228 }
229 }
230
231 extern struct route_in6 ip6_forward_rt;
232
233 void
234 ip6_input(m)
235 struct mbuf *m;
236 {
237 struct ip6_hdr *ip6;
238 int off = sizeof(struct ip6_hdr), nest;
239 u_int32_t plen;
240 u_int32_t rtalert = ~0;
241 int nxt, ours = 0;
242 struct ifnet *deliverifp = NULL;
243 int srcrt = 0;
244
245 #ifdef IPSEC
246 /*
247 * should the inner packet be considered authentic?
248 * see comment in ah4_input().
249 */
250 m->m_flags &= ~M_AUTHIPHDR;
251 m->m_flags &= ~M_AUTHIPDGM;
252 #endif
253
254 /*
255 * make sure we don't have onion peering information into m_tag.
256 */
257 ip6_delaux(m);
258
259 /*
260 * mbuf statistics
261 */
262 if (m->m_flags & M_EXT) {
263 if (m->m_next)
264 ip6stat.ip6s_mext2m++;
265 else
266 ip6stat.ip6s_mext1++;
267 } else {
268 #define M2MMAX (sizeof(ip6stat.ip6s_m2m)/sizeof(ip6stat.ip6s_m2m[0]))
269 if (m->m_next) {
270 if (m->m_flags & M_LOOP) {
271 ip6stat.ip6s_m2m[lo0ifp->if_index]++; /* XXX */
272 } else if (m->m_pkthdr.rcvif->if_index < M2MMAX)
273 ip6stat.ip6s_m2m[m->m_pkthdr.rcvif->if_index]++;
274 else
275 ip6stat.ip6s_m2m[0]++;
276 } else
277 ip6stat.ip6s_m1++;
278 #undef M2MMAX
279 }
280
281 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_receive);
282 ip6stat.ip6s_total++;
283
284 /*
285 * If the IPv6 header is not aligned, slurp it up into a new
286 * mbuf with space for link headers, in the event we forward
287 * it. Otherwise, if it is aligned, make sure the entire base
288 * IPv6 header is in the first mbuf of the chain.
289 */
290 if (IP6_HDR_ALIGNED_P(mtod(m, caddr_t)) == 0) {
291 struct ifnet *inifp = m->m_pkthdr.rcvif;
292 if ((m = m_copyup(m, sizeof(struct ip6_hdr),
293 (max_linkhdr + 3) & ~3)) == NULL) {
294 /* XXXJRT new stat, please */
295 ip6stat.ip6s_toosmall++;
296 in6_ifstat_inc(inifp, ifs6_in_hdrerr);
297 return;
298 }
299 } else if (__predict_false(m->m_len < sizeof(struct ip6_hdr))) {
300 struct ifnet *inifp = m->m_pkthdr.rcvif;
301 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) {
302 ip6stat.ip6s_toosmall++;
303 in6_ifstat_inc(inifp, ifs6_in_hdrerr);
304 return;
305 }
306 }
307
308 ip6 = mtod(m, struct ip6_hdr *);
309
310 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
311 ip6stat.ip6s_badvers++;
312 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr);
313 goto bad;
314 }
315
316 #ifdef PFIL_HOOKS
317 /*
318 * Run through list of hooks for input packets. If there are any
319 * filters which require that additional packets in the flow are
320 * not fast-forwarded, they must clear the M_CANFASTFWD flag.
321 * Note that filters must _never_ set this flag, as another filter
322 * in the list may have previously cleared it.
323 */
324 /*
325 * let ipfilter look at packet on the wire,
326 * not the decapsulated packet.
327 */
328 #ifdef IPSEC
329 if (!ipsec_getnhist(m))
330 #else
331 if (1)
332 #endif
333 {
334 struct in6_addr odst;
335
336 odst = ip6->ip6_dst;
337 if (pfil_run_hooks(&inet6_pfil_hook, &m, m->m_pkthdr.rcvif,
338 PFIL_IN) != 0)
339 return;
340 if (m == NULL)
341 return;
342 ip6 = mtod(m, struct ip6_hdr *);
343 srcrt = !IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst);
344 }
345 #endif /* PFIL_HOOKS */
346
347 ip6stat.ip6s_nxthist[ip6->ip6_nxt]++;
348
349 #ifdef ALTQ
350 if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) {
351 /* packet is dropped by traffic conditioner */
352 return;
353 }
354 #endif
355
356 /*
357 * Check against address spoofing/corruption.
358 */
359 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) ||
360 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) {
361 /*
362 * XXX: "badscope" is not very suitable for a multicast source.
363 */
364 ip6stat.ip6s_badscope++;
365 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
366 goto bad;
367 }
368 /*
369 * The following check is not documented in specs. A malicious
370 * party may be able to use IPv4 mapped addr to confuse tcp/udp stack
371 * and bypass security checks (act as if it was from 127.0.0.1 by using
372 * IPv6 src ::ffff:127.0.0.1). Be cautious.
373 *
374 * This check chokes if we are in an SIIT cloud. As none of BSDs
375 * support IPv4-less kernel compilation, we cannot support SIIT
376 * environment at all. So, it makes more sense for us to reject any
377 * malicious packets for non-SIIT environment, than try to do a
378 * partial support for SIIT environment.
379 */
380 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
381 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
382 ip6stat.ip6s_badscope++;
383 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
384 goto bad;
385 }
386 #if 0
387 /*
388 * Reject packets with IPv4 compatible addresses (auto tunnel).
389 *
390 * The code forbids auto tunnel relay case in RFC1933 (the check is
391 * stronger than RFC1933). We may want to re-enable it if mech-xx
392 * is revised to forbid relaying case.
393 */
394 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) ||
395 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) {
396 ip6stat.ip6s_badscope++;
397 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
398 goto bad;
399 }
400 #endif
401
402 /*
403 * Disambiguate address scope zones (if there is ambiguity).
404 * We first make sure that the original source or destination address
405 * is not in our internal form for scoped addresses. Such addresses
406 * are not necessarily invalid spec-wise, but we cannot accept them due
407 * to the usage conflict.
408 * in6_setscope() then also checks and rejects the cases where src or
409 * dst are the loopback address and the receiving interface
410 * is not loopback.
411 */
412 if (in6_clearscope(&ip6->ip6_src) || in6_clearscope(&ip6->ip6_dst)) {
413 ip6stat.ip6s_badscope++; /* XXX */
414 goto bad;
415 }
416 if (in6_setscope(&ip6->ip6_src, m->m_pkthdr.rcvif, NULL) ||
417 in6_setscope(&ip6->ip6_dst, m->m_pkthdr.rcvif, NULL)) {
418 ip6stat.ip6s_badscope++;
419 goto bad;
420 }
421
422 /*
423 * Multicast check
424 */
425 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
426 struct in6_multi *in6m = 0;
427
428 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast);
429 /*
430 * See if we belong to the destination multicast group on the
431 * arrival interface.
432 */
433 IN6_LOOKUP_MULTI(ip6->ip6_dst, m->m_pkthdr.rcvif, in6m);
434 if (in6m)
435 ours = 1;
436 else if (!ip6_mrouter) {
437 ip6stat.ip6s_notmember++;
438 ip6stat.ip6s_cantforward++;
439 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
440 goto bad;
441 }
442 deliverifp = m->m_pkthdr.rcvif;
443 goto hbhcheck;
444 }
445
446 /*
447 * Unicast check
448 */
449 if (ip6_forward_rt.ro_rt != NULL &&
450 (ip6_forward_rt.ro_rt->rt_flags & RTF_UP) != 0 &&
451 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
452 &((struct sockaddr_in6 *)(&ip6_forward_rt.ro_dst))->sin6_addr))
453 ip6stat.ip6s_forward_cachehit++;
454 else {
455 struct sockaddr_in6 *dst6;
456
457 if (ip6_forward_rt.ro_rt) {
458 /* route is down or destination is different */
459 ip6stat.ip6s_forward_cachemiss++;
460 RTFREE(ip6_forward_rt.ro_rt);
461 ip6_forward_rt.ro_rt = 0;
462 }
463
464 bzero(&ip6_forward_rt.ro_dst, sizeof(struct sockaddr_in6));
465 dst6 = (struct sockaddr_in6 *)&ip6_forward_rt.ro_dst;
466 dst6->sin6_len = sizeof(struct sockaddr_in6);
467 dst6->sin6_family = AF_INET6;
468 dst6->sin6_addr = ip6->ip6_dst;
469
470 rtalloc((struct route *)&ip6_forward_rt);
471 }
472
473 #define rt6_key(r) ((struct sockaddr_in6 *)((r)->rt_nodes->rn_key))
474
475 /*
476 * Accept the packet if the forwarding interface to the destination
477 * according to the routing table is the loopback interface,
478 * unless the associated route has a gateway.
479 * Note that this approach causes to accept a packet if there is a
480 * route to the loopback interface for the destination of the packet.
481 * But we think it's even useful in some situations, e.g. when using
482 * a special daemon which wants to intercept the packet.
483 */
484 if (ip6_forward_rt.ro_rt &&
485 (ip6_forward_rt.ro_rt->rt_flags &
486 (RTF_HOST|RTF_GATEWAY)) == RTF_HOST &&
487 !(ip6_forward_rt.ro_rt->rt_flags & RTF_CLONED) &&
488 #if 0
489 /*
490 * The check below is redundant since the comparison of
491 * the destination and the key of the rtentry has
492 * already done through looking up the routing table.
493 */
494 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
495 &rt6_key(ip6_forward_rt.ro_rt)->sin6_addr) &&
496 #endif
497 ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_LOOP) {
498 struct in6_ifaddr *ia6 =
499 (struct in6_ifaddr *)ip6_forward_rt.ro_rt->rt_ifa;
500 if (ia6->ia6_flags & IN6_IFF_ANYCAST)
501 m->m_flags |= M_ANYCAST6;
502 /*
503 * packets to a tentative, duplicated, or somehow invalid
504 * address must not be accepted.
505 */
506 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) {
507 /* this address is ready */
508 ours = 1;
509 deliverifp = ia6->ia_ifp; /* correct? */
510 goto hbhcheck;
511 } else {
512 /* address is not ready, so discard the packet. */
513 nd6log((LOG_INFO,
514 "ip6_input: packet to an unready address %s->%s\n",
515 ip6_sprintf(&ip6->ip6_src),
516 ip6_sprintf(&ip6->ip6_dst)));
517
518 goto bad;
519 }
520 }
521
522 /*
523 * FAITH (Firewall Aided Internet Translator)
524 */
525 #if defined(NFAITH) && 0 < NFAITH
526 if (ip6_keepfaith) {
527 if (ip6_forward_rt.ro_rt && ip6_forward_rt.ro_rt->rt_ifp &&
528 ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_FAITH) {
529 /* XXX do we need more sanity checks? */
530 ours = 1;
531 deliverifp = ip6_forward_rt.ro_rt->rt_ifp; /* faith */
532 goto hbhcheck;
533 }
534 }
535 #endif
536
537 #if 0
538 {
539 /*
540 * Last resort: check in6_ifaddr for incoming interface.
541 * The code is here until I update the "goto ours hack" code above
542 * working right.
543 */
544 struct ifaddr *ifa;
545 for (ifa = m->m_pkthdr.rcvif->if_addrlist.tqh_first;
546 ifa;
547 ifa = ifa->ifa_list.tqe_next) {
548 if (ifa->ifa_addr == NULL)
549 continue; /* just for safety */
550 if (ifa->ifa_addr->sa_family != AF_INET6)
551 continue;
552 if (IN6_ARE_ADDR_EQUAL(IFA_IN6(ifa), &ip6->ip6_dst)) {
553 ours = 1;
554 deliverifp = ifa->ifa_ifp;
555 goto hbhcheck;
556 }
557 }
558 }
559 #endif
560
561 /*
562 * Now there is no reason to process the packet if it's not our own
563 * and we're not a router.
564 */
565 if (!ip6_forwarding) {
566 ip6stat.ip6s_cantforward++;
567 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
568 goto bad;
569 }
570
571 hbhcheck:
572 /*
573 * record address information into m_tag, if we don't have one yet.
574 * note that we are unable to record it, if the address is not listed
575 * as our interface address (e.g. multicast addresses, addresses
576 * within FAITH prefixes and such).
577 */
578 if (deliverifp && !ip6_getdstifaddr(m)) {
579 struct in6_ifaddr *ia6;
580
581 ia6 = in6_ifawithifp(deliverifp, &ip6->ip6_dst);
582 if (ia6) {
583 if (!ip6_setdstifaddr(m, ia6)) {
584 /*
585 * XXX maybe we should drop the packet here,
586 * as we could not provide enough information
587 * to the upper layers.
588 */
589 }
590 }
591 }
592
593 /*
594 * Process Hop-by-Hop options header if it's contained.
595 * m may be modified in ip6_hopopts_input().
596 * If a JumboPayload option is included, plen will also be modified.
597 */
598 plen = (u_int32_t)ntohs(ip6->ip6_plen);
599 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) {
600 struct ip6_hbh *hbh;
601
602 if (ip6_hopopts_input(&plen, &rtalert, &m, &off)) {
603 #if 0 /*touches NULL pointer*/
604 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
605 #endif
606 return; /* m have already been freed */
607 }
608
609 /* adjust pointer */
610 ip6 = mtod(m, struct ip6_hdr *);
611
612 /*
613 * if the payload length field is 0 and the next header field
614 * indicates Hop-by-Hop Options header, then a Jumbo Payload
615 * option MUST be included.
616 */
617 if (ip6->ip6_plen == 0 && plen == 0) {
618 /*
619 * Note that if a valid jumbo payload option is
620 * contained, ip6_hopopts_input() must set a valid
621 * (non-zero) payload length to the variable plen.
622 */
623 ip6stat.ip6s_badoptions++;
624 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
625 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr);
626 icmp6_error(m, ICMP6_PARAM_PROB,
627 ICMP6_PARAMPROB_HEADER,
628 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6);
629 return;
630 }
631 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr),
632 sizeof(struct ip6_hbh));
633 if (hbh == NULL) {
634 ip6stat.ip6s_tooshort++;
635 return;
636 }
637 KASSERT(IP6_HDR_ALIGNED_P(hbh));
638 nxt = hbh->ip6h_nxt;
639
640 /*
641 * accept the packet if a router alert option is included
642 * and we act as an IPv6 router.
643 */
644 if (rtalert != ~0 && ip6_forwarding)
645 ours = 1;
646 } else
647 nxt = ip6->ip6_nxt;
648
649 /*
650 * Check that the amount of data in the buffers
651 * is as at least much as the IPv6 header would have us expect.
652 * Trim mbufs if longer than we expect.
653 * Drop packet if shorter than we expect.
654 */
655 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) {
656 ip6stat.ip6s_tooshort++;
657 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);
658 goto bad;
659 }
660 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) {
661 if (m->m_len == m->m_pkthdr.len) {
662 m->m_len = sizeof(struct ip6_hdr) + plen;
663 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen;
664 } else
665 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len);
666 }
667
668 /*
669 * Forward if desirable.
670 */
671 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
672 /*
673 * If we are acting as a multicast router, all
674 * incoming multicast packets are passed to the
675 * kernel-level multicast forwarding function.
676 * The packet is returned (relatively) intact; if
677 * ip6_mforward() returns a non-zero value, the packet
678 * must be discarded, else it may be accepted below.
679 */
680 if (ip6_mrouter && ip6_mforward(ip6, m->m_pkthdr.rcvif, m)) {
681 ip6stat.ip6s_cantforward++;
682 m_freem(m);
683 return;
684 }
685 if (!ours) {
686 m_freem(m);
687 return;
688 }
689 } else if (!ours) {
690 ip6_forward(m, srcrt);
691 return;
692 }
693
694 ip6 = mtod(m, struct ip6_hdr *);
695
696 /*
697 * Malicious party may be able to use IPv4 mapped addr to confuse
698 * tcp/udp stack and bypass security checks (act as if it was from
699 * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious.
700 *
701 * For SIIT end node behavior, you may want to disable the check.
702 * However, you will become vulnerable to attacks using IPv4 mapped
703 * source.
704 */
705 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
706 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
707 ip6stat.ip6s_badscope++;
708 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
709 goto bad;
710 }
711
712 /*
713 * Tell launch routine the next header
714 */
715 #ifdef IFA_STATS
716 if (deliverifp != NULL) {
717 struct in6_ifaddr *ia6;
718 ia6 = in6_ifawithifp(deliverifp, &ip6->ip6_dst);
719 if (ia6)
720 ia6->ia_ifa.ifa_data.ifad_inbytes += m->m_pkthdr.len;
721 }
722 #endif
723 ip6stat.ip6s_delivered++;
724 in6_ifstat_inc(deliverifp, ifs6_in_deliver);
725 nest = 0;
726
727 while (nxt != IPPROTO_DONE) {
728 if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) {
729 ip6stat.ip6s_toomanyhdr++;
730 goto bad;
731 }
732
733 /*
734 * protection against faulty packet - there should be
735 * more sanity checks in header chain processing.
736 */
737 if (m->m_pkthdr.len < off) {
738 ip6stat.ip6s_tooshort++;
739 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);
740 goto bad;
741 }
742
743 #ifdef IPSEC
744 /*
745 * enforce IPsec policy checking if we are seeing last header.
746 * note that we do not visit this with protocols with pcb layer
747 * code - like udp/tcp/raw ip.
748 */
749 if ((inet6sw[ip6_protox[nxt]].pr_flags & PR_LASTHDR) != 0 &&
750 ipsec6_in_reject(m, NULL)) {
751 ipsec6stat.in_polvio++;
752 goto bad;
753 }
754 #endif
755
756 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt);
757 }
758 return;
759 bad:
760 m_freem(m);
761 }
762
763 /*
764 * set/grab in6_ifaddr correspond to IPv6 destination address.
765 */
766 static struct m_tag *
767 ip6_setdstifaddr(m, ia6)
768 struct mbuf *m;
769 struct in6_ifaddr *ia6;
770 {
771 struct m_tag *mtag;
772
773 mtag = ip6_addaux(m);
774 if (mtag)
775 ((struct ip6aux *)(mtag + 1))->ip6a_dstia6 = ia6;
776 return mtag; /* NULL if failed to set */
777 }
778
779 struct in6_ifaddr *
780 ip6_getdstifaddr(m)
781 struct mbuf *m;
782 {
783 struct m_tag *mtag;
784
785 mtag = ip6_findaux(m);
786 if (mtag)
787 return ((struct ip6aux *)(mtag + 1))->ip6a_dstia6;
788 else
789 return NULL;
790 }
791
792 /*
793 * Hop-by-Hop options header processing. If a valid jumbo payload option is
794 * included, the real payload length will be stored in plenp.
795 */
796 static int
797 ip6_hopopts_input(plenp, rtalertp, mp, offp)
798 u_int32_t *plenp;
799 u_int32_t *rtalertp; /* XXX: should be stored more smart way */
800 struct mbuf **mp;
801 int *offp;
802 {
803 struct mbuf *m = *mp;
804 int off = *offp, hbhlen;
805 struct ip6_hbh *hbh;
806
807 /* validation of the length of the header */
808 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m,
809 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh));
810 if (hbh == NULL) {
811 ip6stat.ip6s_tooshort++;
812 return -1;
813 }
814 hbhlen = (hbh->ip6h_len + 1) << 3;
815 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr),
816 hbhlen);
817 if (hbh == NULL) {
818 ip6stat.ip6s_tooshort++;
819 return -1;
820 }
821 KASSERT(IP6_HDR_ALIGNED_P(hbh));
822 off += hbhlen;
823 hbhlen -= sizeof(struct ip6_hbh);
824
825 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh),
826 hbhlen, rtalertp, plenp) < 0)
827 return (-1);
828
829 *offp = off;
830 *mp = m;
831 return (0);
832 }
833
834 /*
835 * Search header for all Hop-by-hop options and process each option.
836 * This function is separate from ip6_hopopts_input() in order to
837 * handle a case where the sending node itself process its hop-by-hop
838 * options header. In such a case, the function is called from ip6_output().
839 *
840 * The function assumes that hbh header is located right after the IPv6 header
841 * (RFC2460 p7), opthead is pointer into data content in m, and opthead to
842 * opthead + hbhlen is located in continuous memory region.
843 */
844 int
845 ip6_process_hopopts(m, opthead, hbhlen, rtalertp, plenp)
846 struct mbuf *m;
847 u_int8_t *opthead;
848 int hbhlen;
849 u_int32_t *rtalertp;
850 u_int32_t *plenp;
851 {
852 struct ip6_hdr *ip6;
853 int optlen = 0;
854 u_int8_t *opt = opthead;
855 u_int16_t rtalert_val;
856 u_int32_t jumboplen;
857 const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh);
858
859 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) {
860 switch (*opt) {
861 case IP6OPT_PAD1:
862 optlen = 1;
863 break;
864 case IP6OPT_PADN:
865 if (hbhlen < IP6OPT_MINLEN) {
866 ip6stat.ip6s_toosmall++;
867 goto bad;
868 }
869 optlen = *(opt + 1) + 2;
870 break;
871 case IP6OPT_RTALERT:
872 /* XXX may need check for alignment */
873 if (hbhlen < IP6OPT_RTALERT_LEN) {
874 ip6stat.ip6s_toosmall++;
875 goto bad;
876 }
877 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) {
878 /* XXX stat */
879 icmp6_error(m, ICMP6_PARAM_PROB,
880 ICMP6_PARAMPROB_HEADER,
881 erroff + opt + 1 - opthead);
882 return (-1);
883 }
884 optlen = IP6OPT_RTALERT_LEN;
885 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2);
886 *rtalertp = ntohs(rtalert_val);
887 break;
888 case IP6OPT_JUMBO:
889 /* XXX may need check for alignment */
890 if (hbhlen < IP6OPT_JUMBO_LEN) {
891 ip6stat.ip6s_toosmall++;
892 goto bad;
893 }
894 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) {
895 /* XXX stat */
896 icmp6_error(m, ICMP6_PARAM_PROB,
897 ICMP6_PARAMPROB_HEADER,
898 erroff + opt + 1 - opthead);
899 return (-1);
900 }
901 optlen = IP6OPT_JUMBO_LEN;
902
903 /*
904 * IPv6 packets that have non 0 payload length
905 * must not contain a jumbo payload option.
906 */
907 ip6 = mtod(m, struct ip6_hdr *);
908 if (ip6->ip6_plen) {
909 ip6stat.ip6s_badoptions++;
910 icmp6_error(m, ICMP6_PARAM_PROB,
911 ICMP6_PARAMPROB_HEADER,
912 erroff + opt - opthead);
913 return (-1);
914 }
915
916 /*
917 * We may see jumbolen in unaligned location, so
918 * we'd need to perform bcopy().
919 */
920 bcopy(opt + 2, &jumboplen, sizeof(jumboplen));
921 jumboplen = (u_int32_t)htonl(jumboplen);
922
923 #if 1
924 /*
925 * if there are multiple jumbo payload options,
926 * *plenp will be non-zero and the packet will be
927 * rejected.
928 * the behavior may need some debate in ipngwg -
929 * multiple options does not make sense, however,
930 * there's no explicit mention in specification.
931 */
932 if (*plenp != 0) {
933 ip6stat.ip6s_badoptions++;
934 icmp6_error(m, ICMP6_PARAM_PROB,
935 ICMP6_PARAMPROB_HEADER,
936 erroff + opt + 2 - opthead);
937 return (-1);
938 }
939 #endif
940
941 /*
942 * jumbo payload length must be larger than 65535.
943 */
944 if (jumboplen <= IPV6_MAXPACKET) {
945 ip6stat.ip6s_badoptions++;
946 icmp6_error(m, ICMP6_PARAM_PROB,
947 ICMP6_PARAMPROB_HEADER,
948 erroff + opt + 2 - opthead);
949 return (-1);
950 }
951 *plenp = jumboplen;
952
953 break;
954 default: /* unknown option */
955 if (hbhlen < IP6OPT_MINLEN) {
956 ip6stat.ip6s_toosmall++;
957 goto bad;
958 }
959 optlen = ip6_unknown_opt(opt, m,
960 erroff + opt - opthead);
961 if (optlen == -1)
962 return (-1);
963 optlen += 2;
964 break;
965 }
966 }
967
968 return (0);
969
970 bad:
971 m_freem(m);
972 return (-1);
973 }
974
975 /*
976 * Unknown option processing.
977 * The third argument `off' is the offset from the IPv6 header to the option,
978 * which is necessary if the IPv6 header the and option header and IPv6 header
979 * is not continuous in order to return an ICMPv6 error.
980 */
981 int
982 ip6_unknown_opt(optp, m, off)
983 u_int8_t *optp;
984 struct mbuf *m;
985 int off;
986 {
987 struct ip6_hdr *ip6;
988
989 switch (IP6OPT_TYPE(*optp)) {
990 case IP6OPT_TYPE_SKIP: /* ignore the option */
991 return ((int)*(optp + 1));
992 case IP6OPT_TYPE_DISCARD: /* silently discard */
993 m_freem(m);
994 return (-1);
995 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */
996 ip6stat.ip6s_badoptions++;
997 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off);
998 return (-1);
999 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */
1000 ip6stat.ip6s_badoptions++;
1001 ip6 = mtod(m, struct ip6_hdr *);
1002 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) ||
1003 (m->m_flags & (M_BCAST|M_MCAST)))
1004 m_freem(m);
1005 else
1006 icmp6_error(m, ICMP6_PARAM_PROB,
1007 ICMP6_PARAMPROB_OPTION, off);
1008 return (-1);
1009 }
1010
1011 m_freem(m); /* XXX: NOTREACHED */
1012 return (-1);
1013 }
1014
1015 /*
1016 * Create the "control" list for this pcb.
1017 *
1018 * The routine will be called from upper layer handlers like tcp6_input().
1019 * Thus the routine assumes that the caller (tcp6_input) have already
1020 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the
1021 * very first mbuf on the mbuf chain.
1022 * We may want to add some infinite loop prevention or sanity checks for safety.
1023 * (This applies only when you are using KAME mbuf chain restriction, i.e.
1024 * you are using IP6_EXTHDR_CHECK() not m_pulldown())
1025 */
1026 void
1027 ip6_savecontrol(in6p, mp, ip6, m)
1028 struct in6pcb *in6p;
1029 struct mbuf **mp;
1030 struct ip6_hdr *ip6;
1031 struct mbuf *m;
1032 {
1033 #ifdef SO_TIMESTAMP
1034 if (in6p->in6p_socket->so_options & SO_TIMESTAMP) {
1035 struct timeval tv;
1036
1037 microtime(&tv);
1038 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv),
1039 SCM_TIMESTAMP, SOL_SOCKET);
1040 if (*mp)
1041 mp = &(*mp)->m_next;
1042 }
1043 #endif
1044 if (in6p->in6p_flags & IN6P_RECVDSTADDR) {
1045 *mp = sbcreatecontrol((caddr_t) &ip6->ip6_dst,
1046 sizeof(struct in6_addr), IPV6_RECVDSTADDR, IPPROTO_IPV6);
1047 if (*mp)
1048 mp = &(*mp)->m_next;
1049 }
1050
1051 #ifdef noyet
1052 /* options were tossed above */
1053 if (in6p->in6p_flags & IN6P_RECVOPTS)
1054 /* broken */
1055 /* ip6_srcroute doesn't do what we want here, need to fix */
1056 if (in6p->in6p_flags & IPV6P_RECVRETOPTS)
1057 /* broken */
1058 #endif
1059
1060 /* RFC 2292 sec. 5 */
1061 if ((in6p->in6p_flags & IN6P_PKTINFO) != 0) {
1062 struct in6_pktinfo pi6;
1063 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr));
1064 in6_clearscope(&pi6.ipi6_addr); /* XXX */
1065 pi6.ipi6_ifindex = m->m_pkthdr.rcvif ?
1066 m->m_pkthdr.rcvif->if_index : 0;
1067 *mp = sbcreatecontrol((caddr_t) &pi6,
1068 sizeof(struct in6_pktinfo), IPV6_PKTINFO, IPPROTO_IPV6);
1069 if (*mp)
1070 mp = &(*mp)->m_next;
1071 }
1072 if (in6p->in6p_flags & IN6P_HOPLIMIT) {
1073 int hlim = ip6->ip6_hlim & 0xff;
1074 *mp = sbcreatecontrol((caddr_t) &hlim, sizeof(int),
1075 IPV6_HOPLIMIT, IPPROTO_IPV6);
1076 if (*mp)
1077 mp = &(*mp)->m_next;
1078 }
1079 /* IN6P_NEXTHOP - for outgoing packet only */
1080
1081 /*
1082 * IPV6_HOPOPTS socket option. Recall that we required super-user
1083 * privilege for the option (see ip6_ctloutput), but it might be too
1084 * strict, since there might be some hop-by-hop options which can be
1085 * returned to normal user.
1086 * See also RFC 2292 section 6.
1087 */
1088 if ((in6p->in6p_flags & IN6P_HOPOPTS) != 0) {
1089 /*
1090 * Check if a hop-by-hop options header is contatined in the
1091 * received packet, and if so, store the options as ancillary
1092 * data. Note that a hop-by-hop options header must be
1093 * just after the IPv6 header, which fact is assured through
1094 * the IPv6 input processing.
1095 */
1096 struct ip6_hdr *xip6 = mtod(m, struct ip6_hdr *);
1097 if (xip6->ip6_nxt == IPPROTO_HOPOPTS) {
1098 struct ip6_hbh *hbh;
1099 int hbhlen;
1100 struct mbuf *ext;
1101
1102 ext = ip6_pullexthdr(m, sizeof(struct ip6_hdr),
1103 xip6->ip6_nxt);
1104 if (ext == NULL) {
1105 ip6stat.ip6s_tooshort++;
1106 return;
1107 }
1108 hbh = mtod(ext, struct ip6_hbh *);
1109 hbhlen = (hbh->ip6h_len + 1) << 3;
1110 if (hbhlen != ext->m_len) {
1111 m_freem(ext);
1112 ip6stat.ip6s_tooshort++;
1113 return;
1114 }
1115
1116 /*
1117 * XXX: We copy whole the header even if a jumbo
1118 * payload option is included, which option is to
1119 * be removed before returning in the RFC 2292.
1120 * But it's too painful operation...
1121 */
1122 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen,
1123 IPV6_HOPOPTS, IPPROTO_IPV6);
1124 if (*mp)
1125 mp = &(*mp)->m_next;
1126 m_freem(ext);
1127 }
1128 }
1129
1130 /* IPV6_DSTOPTS and IPV6_RTHDR socket options */
1131 if (in6p->in6p_flags & (IN6P_DSTOPTS | IN6P_RTHDR)) {
1132 struct ip6_hdr *xip6 = mtod(m, struct ip6_hdr *);
1133 int nxt = xip6->ip6_nxt, off = sizeof(struct ip6_hdr);
1134
1135 /*
1136 * Search for destination options headers or routing
1137 * header(s) through the header chain, and stores each
1138 * header as ancillary data.
1139 * Note that the order of the headers remains in
1140 * the chain of ancillary data.
1141 */
1142 while (1) { /* is explicit loop prevention necessary? */
1143 struct ip6_ext *ip6e = NULL;
1144 int elen;
1145 struct mbuf *ext = NULL;
1146
1147 /*
1148 * if it is not an extension header, don't try to
1149 * pull it from the chain.
1150 */
1151 switch (nxt) {
1152 case IPPROTO_DSTOPTS:
1153 case IPPROTO_ROUTING:
1154 case IPPROTO_HOPOPTS:
1155 case IPPROTO_AH: /* is it possible? */
1156 break;
1157 default:
1158 goto loopend;
1159 }
1160
1161 ext = ip6_pullexthdr(m, off, nxt);
1162 if (ext == NULL) {
1163 ip6stat.ip6s_tooshort++;
1164 return;
1165 }
1166 ip6e = mtod(ext, struct ip6_ext *);
1167 if (nxt == IPPROTO_AH)
1168 elen = (ip6e->ip6e_len + 2) << 2;
1169 else
1170 elen = (ip6e->ip6e_len + 1) << 3;
1171 if (elen != ext->m_len) {
1172 m_freem(ext);
1173 ip6stat.ip6s_tooshort++;
1174 return;
1175 }
1176 KASSERT(IP6_HDR_ALIGNED_P(ip6e));
1177
1178 switch (nxt) {
1179 case IPPROTO_DSTOPTS:
1180 if (!in6p->in6p_flags & IN6P_DSTOPTS)
1181 break;
1182
1183 *mp = sbcreatecontrol((caddr_t)ip6e, elen,
1184 IPV6_DSTOPTS, IPPROTO_IPV6);
1185 if (*mp)
1186 mp = &(*mp)->m_next;
1187 break;
1188
1189 case IPPROTO_ROUTING:
1190 if (!in6p->in6p_flags & IN6P_RTHDR)
1191 break;
1192
1193 *mp = sbcreatecontrol((caddr_t)ip6e, elen,
1194 IPV6_RTHDR, IPPROTO_IPV6);
1195 if (*mp)
1196 mp = &(*mp)->m_next;
1197 break;
1198
1199 case IPPROTO_HOPOPTS:
1200 case IPPROTO_AH: /* is it possible? */
1201 break;
1202
1203 default:
1204 /*
1205 * other cases have been filtered in the above.
1206 * none will visit this case. here we supply
1207 * the code just in case (nxt overwritten or
1208 * other cases).
1209 */
1210 m_freem(ext);
1211 goto loopend;
1212
1213 }
1214
1215 /* proceed with the next header. */
1216 off += elen;
1217 nxt = ip6e->ip6e_nxt;
1218 ip6e = NULL;
1219 m_freem(ext);
1220 ext = NULL;
1221 }
1222 loopend:
1223 ;
1224 }
1225 }
1226
1227 /*
1228 * pull single extension header from mbuf chain. returns single mbuf that
1229 * contains the result, or NULL on error.
1230 */
1231 static struct mbuf *
1232 ip6_pullexthdr(m, off, nxt)
1233 struct mbuf *m;
1234 size_t off;
1235 int nxt;
1236 {
1237 struct ip6_ext ip6e;
1238 size_t elen;
1239 struct mbuf *n;
1240
1241 #ifdef DIAGNOSTIC
1242 switch (nxt) {
1243 case IPPROTO_DSTOPTS:
1244 case IPPROTO_ROUTING:
1245 case IPPROTO_HOPOPTS:
1246 case IPPROTO_AH: /* is it possible? */
1247 break;
1248 default:
1249 printf("ip6_pullexthdr: invalid nxt=%d\n", nxt);
1250 }
1251 #endif
1252
1253 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
1254 if (nxt == IPPROTO_AH)
1255 elen = (ip6e.ip6e_len + 2) << 2;
1256 else
1257 elen = (ip6e.ip6e_len + 1) << 3;
1258
1259 MGET(n, M_DONTWAIT, MT_DATA);
1260 if (n && elen >= MLEN) {
1261 MCLGET(n, M_DONTWAIT);
1262 if ((n->m_flags & M_EXT) == 0) {
1263 m_free(n);
1264 n = NULL;
1265 }
1266 }
1267 if (!n)
1268 return NULL;
1269
1270 n->m_len = 0;
1271 if (elen >= M_TRAILINGSPACE(n)) {
1272 m_free(n);
1273 return NULL;
1274 }
1275
1276 m_copydata(m, off, elen, mtod(n, caddr_t));
1277 n->m_len = elen;
1278 return n;
1279 }
1280
1281 /*
1282 * Get pointer to the previous header followed by the header
1283 * currently processed.
1284 * XXX: This function supposes that
1285 * M includes all headers,
1286 * the next header field and the header length field of each header
1287 * are valid, and
1288 * the sum of each header length equals to OFF.
1289 * Because of these assumptions, this function must be called very
1290 * carefully. Moreover, it will not be used in the near future when
1291 * we develop `neater' mechanism to process extension headers.
1292 */
1293 u_int8_t *
1294 ip6_get_prevhdr(m, off)
1295 struct mbuf *m;
1296 int off;
1297 {
1298 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1299
1300 if (off == sizeof(struct ip6_hdr))
1301 return (&ip6->ip6_nxt);
1302 else {
1303 int len, nxt;
1304 struct ip6_ext *ip6e = NULL;
1305
1306 nxt = ip6->ip6_nxt;
1307 len = sizeof(struct ip6_hdr);
1308 while (len < off) {
1309 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len);
1310
1311 switch (nxt) {
1312 case IPPROTO_FRAGMENT:
1313 len += sizeof(struct ip6_frag);
1314 break;
1315 case IPPROTO_AH:
1316 len += (ip6e->ip6e_len + 2) << 2;
1317 break;
1318 default:
1319 len += (ip6e->ip6e_len + 1) << 3;
1320 break;
1321 }
1322 nxt = ip6e->ip6e_nxt;
1323 }
1324 if (ip6e)
1325 return (&ip6e->ip6e_nxt);
1326 else
1327 return NULL;
1328 }
1329 }
1330
1331 /*
1332 * get next header offset. m will be retained.
1333 */
1334 int
1335 ip6_nexthdr(m, off, proto, nxtp)
1336 struct mbuf *m;
1337 int off;
1338 int proto;
1339 int *nxtp;
1340 {
1341 struct ip6_hdr ip6;
1342 struct ip6_ext ip6e;
1343 struct ip6_frag fh;
1344
1345 /* just in case */
1346 if (m == NULL)
1347 panic("ip6_nexthdr: m == NULL");
1348 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off)
1349 return -1;
1350
1351 switch (proto) {
1352 case IPPROTO_IPV6:
1353 /* do not chase beyond intermediate IPv6 headers */
1354 if (off != 0)
1355 return -1;
1356 if (m->m_pkthdr.len < off + sizeof(ip6))
1357 return -1;
1358 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6);
1359 if (nxtp)
1360 *nxtp = ip6.ip6_nxt;
1361 off += sizeof(ip6);
1362 return off;
1363
1364 case IPPROTO_FRAGMENT:
1365 /*
1366 * terminate parsing if it is not the first fragment,
1367 * it does not make sense to parse through it.
1368 */
1369 if (m->m_pkthdr.len < off + sizeof(fh))
1370 return -1;
1371 m_copydata(m, off, sizeof(fh), (caddr_t)&fh);
1372 if ((fh.ip6f_offlg & IP6F_OFF_MASK) != 0)
1373 return -1;
1374 if (nxtp)
1375 *nxtp = fh.ip6f_nxt;
1376 off += sizeof(struct ip6_frag);
1377 return off;
1378
1379 case IPPROTO_AH:
1380 if (m->m_pkthdr.len < off + sizeof(ip6e))
1381 return -1;
1382 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
1383 if (nxtp)
1384 *nxtp = ip6e.ip6e_nxt;
1385 off += (ip6e.ip6e_len + 2) << 2;
1386 if (m->m_pkthdr.len < off)
1387 return -1;
1388 return off;
1389
1390 case IPPROTO_HOPOPTS:
1391 case IPPROTO_ROUTING:
1392 case IPPROTO_DSTOPTS:
1393 if (m->m_pkthdr.len < off + sizeof(ip6e))
1394 return -1;
1395 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
1396 if (nxtp)
1397 *nxtp = ip6e.ip6e_nxt;
1398 off += (ip6e.ip6e_len + 1) << 3;
1399 if (m->m_pkthdr.len < off)
1400 return -1;
1401 return off;
1402
1403 case IPPROTO_NONE:
1404 case IPPROTO_ESP:
1405 case IPPROTO_IPCOMP:
1406 /* give up */
1407 return -1;
1408
1409 default:
1410 return -1;
1411 }
1412 }
1413
1414 /*
1415 * get offset for the last header in the chain. m will be kept untainted.
1416 */
1417 int
1418 ip6_lasthdr(m, off, proto, nxtp)
1419 struct mbuf *m;
1420 int off;
1421 int proto;
1422 int *nxtp;
1423 {
1424 int newoff;
1425 int nxt;
1426
1427 if (!nxtp) {
1428 nxt = -1;
1429 nxtp = &nxt;
1430 }
1431 while (1) {
1432 newoff = ip6_nexthdr(m, off, proto, nxtp);
1433 if (newoff < 0)
1434 return off;
1435 else if (newoff < off)
1436 return -1; /* invalid */
1437 else if (newoff == off)
1438 return newoff;
1439
1440 off = newoff;
1441 proto = *nxtp;
1442 }
1443 }
1444
1445 struct m_tag *
1446 ip6_addaux(m)
1447 struct mbuf *m;
1448 {
1449 struct m_tag *mtag;
1450
1451 mtag = m_tag_find(m, PACKET_TAG_INET6, NULL);
1452 if (!mtag) {
1453 mtag = m_tag_get(PACKET_TAG_INET6, sizeof(struct ip6aux),
1454 M_NOWAIT);
1455 if (mtag) {
1456 m_tag_prepend(m, mtag);
1457 bzero(mtag + 1, sizeof(struct ip6aux));
1458 }
1459 }
1460 return mtag;
1461 }
1462
1463 struct m_tag *
1464 ip6_findaux(m)
1465 struct mbuf *m;
1466 {
1467 struct m_tag *mtag;
1468
1469 mtag = m_tag_find(m, PACKET_TAG_INET6, NULL);
1470 return mtag;
1471 }
1472
1473 void
1474 ip6_delaux(m)
1475 struct mbuf *m;
1476 {
1477 struct m_tag *mtag;
1478
1479 mtag = m_tag_find(m, PACKET_TAG_INET6, NULL);
1480 if (mtag)
1481 m_tag_delete(m, mtag);
1482 }
1483
1484 /*
1485 * System control for IP6
1486 */
1487
1488 u_char inet6ctlerrmap[PRC_NCMDS] = {
1489 0, 0, 0, 0,
1490 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH,
1491 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED,
1492 EMSGSIZE, EHOSTUNREACH, 0, 0,
1493 0, 0, 0, 0,
1494 ENOPROTOOPT
1495 };
1496
1497 SYSCTL_SETUP(sysctl_net_inet6_ip6_setup, "sysctl net.inet6.ip6 subtree setup")
1498 {
1499
1500 sysctl_createv(clog, 0, NULL, NULL,
1501 CTLFLAG_PERMANENT,
1502 CTLTYPE_NODE, "net", NULL,
1503 NULL, 0, NULL, 0,
1504 CTL_NET, CTL_EOL);
1505 sysctl_createv(clog, 0, NULL, NULL,
1506 CTLFLAG_PERMANENT,
1507 CTLTYPE_NODE, "inet6",
1508 SYSCTL_DESCR("PF_INET6 related settings"),
1509 NULL, 0, NULL, 0,
1510 CTL_NET, PF_INET6, CTL_EOL);
1511 sysctl_createv(clog, 0, NULL, NULL,
1512 CTLFLAG_PERMANENT,
1513 CTLTYPE_NODE, "ip6",
1514 SYSCTL_DESCR("IPv6 related settings"),
1515 NULL, 0, NULL, 0,
1516 CTL_NET, PF_INET6, IPPROTO_IPV6, CTL_EOL);
1517
1518 sysctl_createv(clog, 0, NULL, NULL,
1519 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1520 CTLTYPE_INT, "forwarding",
1521 SYSCTL_DESCR("Enable forwarding of INET6 datagrams"),
1522 NULL, 0, &ip6_forwarding, 0,
1523 CTL_NET, PF_INET6, IPPROTO_IPV6,
1524 IPV6CTL_FORWARDING, CTL_EOL);
1525 sysctl_createv(clog, 0, NULL, NULL,
1526 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1527 CTLTYPE_INT, "redirect",
1528 SYSCTL_DESCR("Enable sending of ICMPv6 redirect messages"),
1529 NULL, 0, &ip6_sendredirects, 0,
1530 CTL_NET, PF_INET6, IPPROTO_IPV6,
1531 IPV6CTL_SENDREDIRECTS, CTL_EOL);
1532 sysctl_createv(clog, 0, NULL, NULL,
1533 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1534 CTLTYPE_INT, "hlim",
1535 SYSCTL_DESCR("Hop limit for an INET6 datagram"),
1536 NULL, 0, &ip6_defhlim, 0,
1537 CTL_NET, PF_INET6, IPPROTO_IPV6,
1538 IPV6CTL_DEFHLIM, CTL_EOL);
1539 #ifdef notyet
1540 sysctl_createv(clog, 0, NULL, NULL,
1541 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1542 CTLTYPE_INT, "mtu", NULL,
1543 NULL, 0, &, 0,
1544 CTL_NET, PF_INET6, IPPROTO_IPV6,
1545 IPV6CTL_DEFMTU, CTL_EOL);
1546 #endif
1547 #ifdef __no_idea__
1548 sysctl_createv(clog, 0, NULL, NULL,
1549 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1550 CTLTYPE_INT, "forwsrcrt", NULL,
1551 NULL, 0, &?, 0,
1552 CTL_NET, PF_INET6, IPPROTO_IPV6,
1553 IPV6CTL_FORWSRCRT, CTL_EOL);
1554 sysctl_createv(clog, 0, NULL, NULL,
1555 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1556 CTLTYPE_STRUCT, "mrtstats", NULL,
1557 NULL, 0, &?, sizeof(?),
1558 CTL_NET, PF_INET6, IPPROTO_IPV6,
1559 IPV6CTL_MRTSTATS, CTL_EOL);
1560 sysctl_createv(clog, 0, NULL, NULL,
1561 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1562 CTLTYPE_?, "mrtproto", NULL,
1563 NULL, 0, &?, sizeof(?),
1564 CTL_NET, PF_INET6, IPPROTO_IPV6,
1565 IPV6CTL_MRTPROTO, CTL_EOL);
1566 #endif
1567 sysctl_createv(clog, 0, NULL, NULL,
1568 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1569 CTLTYPE_INT, "maxfragpackets",
1570 SYSCTL_DESCR("Maximum number of fragments to buffer "
1571 "for reassembly"),
1572 NULL, 0, &ip6_maxfragpackets, 0,
1573 CTL_NET, PF_INET6, IPPROTO_IPV6,
1574 IPV6CTL_MAXFRAGPACKETS, CTL_EOL);
1575 #ifdef __no_idea__
1576 sysctl_createv(clog, 0, NULL, NULL,
1577 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1578 CTLTYPE_INT, "sourcecheck", NULL,
1579 NULL, 0, &?, 0,
1580 CTL_NET, PF_INET6, IPPROTO_IPV6,
1581 IPV6CTL_SOURCECHECK, CTL_EOL);
1582 sysctl_createv(clog, 0, NULL, NULL,
1583 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1584 CTLTYPE_INT, "sourcecheck_logint", NULL,
1585 NULL, 0, &?, 0,
1586 CTL_NET, PF_INET6, IPPROTO_IPV6,
1587 IPV6CTL_SOURCECHECK_LOGINT, CTL_EOL);
1588 #endif
1589 sysctl_createv(clog, 0, NULL, NULL,
1590 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1591 CTLTYPE_INT, "accept_rtadv",
1592 SYSCTL_DESCR("Accept router advertisements"),
1593 NULL, 0, &ip6_accept_rtadv, 0,
1594 CTL_NET, PF_INET6, IPPROTO_IPV6,
1595 IPV6CTL_ACCEPT_RTADV, CTL_EOL);
1596 sysctl_createv(clog, 0, NULL, NULL,
1597 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1598 CTLTYPE_INT, "keepfaith",
1599 SYSCTL_DESCR("Activate faith interface"),
1600 NULL, 0, &ip6_keepfaith, 0,
1601 CTL_NET, PF_INET6, IPPROTO_IPV6,
1602 IPV6CTL_KEEPFAITH, CTL_EOL);
1603 sysctl_createv(clog, 0, NULL, NULL,
1604 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1605 CTLTYPE_INT, "log_interval",
1606 SYSCTL_DESCR("Minumum interval between logging "
1607 "unroutable packets"),
1608 NULL, 0, &ip6_log_interval, 0,
1609 CTL_NET, PF_INET6, IPPROTO_IPV6,
1610 IPV6CTL_LOG_INTERVAL, CTL_EOL);
1611 sysctl_createv(clog, 0, NULL, NULL,
1612 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1613 CTLTYPE_INT, "hdrnestlimit",
1614 SYSCTL_DESCR("Maximum number of nested IPv6 headers"),
1615 NULL, 0, &ip6_hdrnestlimit, 0,
1616 CTL_NET, PF_INET6, IPPROTO_IPV6,
1617 IPV6CTL_HDRNESTLIMIT, CTL_EOL);
1618 sysctl_createv(clog, 0, NULL, NULL,
1619 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1620 CTLTYPE_INT, "dad_count",
1621 SYSCTL_DESCR("Number of Duplicate Address Detection "
1622 "probes to send"),
1623 NULL, 0, &ip6_dad_count, 0,
1624 CTL_NET, PF_INET6, IPPROTO_IPV6,
1625 IPV6CTL_DAD_COUNT, CTL_EOL);
1626 sysctl_createv(clog, 0, NULL, NULL,
1627 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1628 CTLTYPE_INT, "auto_flowlabel",
1629 SYSCTL_DESCR("Assign random IPv6 flow labels"),
1630 NULL, 0, &ip6_auto_flowlabel, 0,
1631 CTL_NET, PF_INET6, IPPROTO_IPV6,
1632 IPV6CTL_AUTO_FLOWLABEL, CTL_EOL);
1633 sysctl_createv(clog, 0, NULL, NULL,
1634 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1635 CTLTYPE_INT, "defmcasthlim",
1636 SYSCTL_DESCR("Default multicast hop limit"),
1637 NULL, 0, &ip6_defmcasthlim, 0,
1638 CTL_NET, PF_INET6, IPPROTO_IPV6,
1639 IPV6CTL_DEFMCASTHLIM, CTL_EOL);
1640 #if NGIF > 0
1641 sysctl_createv(clog, 0, NULL, NULL,
1642 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1643 CTLTYPE_INT, "gifhlim",
1644 SYSCTL_DESCR("Default hop limit for a gif tunnel datagram"),
1645 NULL, 0, &ip6_gif_hlim, 0,
1646 CTL_NET, PF_INET6, IPPROTO_IPV6,
1647 IPV6CTL_GIF_HLIM, CTL_EOL);
1648 #endif /* NGIF */
1649 sysctl_createv(clog, 0, NULL, NULL,
1650 CTLFLAG_PERMANENT,
1651 CTLTYPE_STRING, "kame_version",
1652 SYSCTL_DESCR("KAME Version"),
1653 NULL, 0, __UNCONST(__KAME_VERSION), 0,
1654 CTL_NET, PF_INET6, IPPROTO_IPV6,
1655 IPV6CTL_KAME_VERSION, CTL_EOL);
1656 sysctl_createv(clog, 0, NULL, NULL,
1657 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1658 CTLTYPE_INT, "use_deprecated",
1659 SYSCTL_DESCR("Allow use of deprecated addresses as "
1660 "source addresses"),
1661 NULL, 0, &ip6_use_deprecated, 0,
1662 CTL_NET, PF_INET6, IPPROTO_IPV6,
1663 IPV6CTL_USE_DEPRECATED, CTL_EOL);
1664 sysctl_createv(clog, 0, NULL, NULL,
1665 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1666 CTLTYPE_INT, "rr_prune", NULL,
1667 NULL, 0, &ip6_rr_prune, 0,
1668 CTL_NET, PF_INET6, IPPROTO_IPV6,
1669 IPV6CTL_RR_PRUNE, CTL_EOL);
1670 sysctl_createv(clog, 0, NULL, NULL,
1671 CTLFLAG_PERMANENT
1672 #ifndef INET6_BINDV6ONLY
1673 |CTLFLAG_READWRITE,
1674 #endif
1675 CTLTYPE_INT, "v6only",
1676 SYSCTL_DESCR("Disallow PF_INET6 sockets from connecting "
1677 "to PF_INET sockets"),
1678 NULL, 0, &ip6_v6only, 0,
1679 CTL_NET, PF_INET6, IPPROTO_IPV6,
1680 IPV6CTL_V6ONLY, CTL_EOL);
1681 sysctl_createv(clog, 0, NULL, NULL,
1682 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1683 CTLTYPE_INT, "anonportmin",
1684 SYSCTL_DESCR("Lowest ephemeral port number to assign"),
1685 sysctl_net_inet_ip_ports, 0, &ip6_anonportmin, 0,
1686 CTL_NET, PF_INET6, IPPROTO_IPV6,
1687 IPV6CTL_ANONPORTMIN, CTL_EOL);
1688 sysctl_createv(clog, 0, NULL, NULL,
1689 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1690 CTLTYPE_INT, "anonportmax",
1691 SYSCTL_DESCR("Highest ephemeral port number to assign"),
1692 sysctl_net_inet_ip_ports, 0, &ip6_anonportmax, 0,
1693 CTL_NET, PF_INET6, IPPROTO_IPV6,
1694 IPV6CTL_ANONPORTMAX, CTL_EOL);
1695 #ifndef IPNOPRIVPORTS
1696 sysctl_createv(clog, 0, NULL, NULL,
1697 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1698 CTLTYPE_INT, "lowportmin",
1699 SYSCTL_DESCR("Lowest privileged ephemeral port number "
1700 "to assign"),
1701 sysctl_net_inet_ip_ports, 0, &ip6_lowportmin, 0,
1702 CTL_NET, PF_INET6, IPPROTO_IPV6,
1703 IPV6CTL_LOWPORTMIN, CTL_EOL);
1704 sysctl_createv(clog, 0, NULL, NULL,
1705 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1706 CTLTYPE_INT, "lowportmax",
1707 SYSCTL_DESCR("Highest privileged ephemeral port number "
1708 "to assign"),
1709 sysctl_net_inet_ip_ports, 0, &ip6_lowportmax, 0,
1710 CTL_NET, PF_INET6, IPPROTO_IPV6,
1711 IPV6CTL_LOWPORTMAX, CTL_EOL);
1712 #endif /* IPNOPRIVPORTS */
1713 sysctl_createv(clog, 0, NULL, NULL,
1714 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1715 CTLTYPE_INT, "use_tempaddr",
1716 SYSCTL_DESCR("Use temporary address"),
1717 NULL, 0, &ip6_use_tempaddr, 0,
1718 CTL_NET, PF_INET6, IPPROTO_IPV6,
1719 CTL_CREATE, CTL_EOL);
1720 sysctl_createv(clog, 0, NULL, NULL,
1721 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1722 CTLTYPE_INT, "temppltime",
1723 SYSCTL_DESCR("preferred lifetime of a temporary address"),
1724 NULL, 0, &ip6_temp_preferred_lifetime, 0,
1725 CTL_NET, PF_INET6, IPPROTO_IPV6,
1726 CTL_CREATE, CTL_EOL);
1727 sysctl_createv(clog, 0, NULL, NULL,
1728 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1729 CTLTYPE_INT, "tempvltime",
1730 SYSCTL_DESCR("valid lifetime of a temporary address"),
1731 NULL, 0, &ip6_temp_valid_lifetime, 0,
1732 CTL_NET, PF_INET6, IPPROTO_IPV6,
1733 CTL_CREATE, CTL_EOL);
1734 sysctl_createv(clog, 0, NULL, NULL,
1735 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1736 CTLTYPE_INT, "maxfrags",
1737 SYSCTL_DESCR("Maximum fragments in reassembly queue"),
1738 NULL, 0, &ip6_maxfrags, 0,
1739 CTL_NET, PF_INET6, IPPROTO_IPV6,
1740 IPV6CTL_MAXFRAGS, CTL_EOL);
1741 sysctl_createv(clog, 0, NULL, NULL,
1742 CTLFLAG_PERMANENT,
1743 CTLTYPE_STRUCT, "stats",
1744 SYSCTL_DESCR("IPv6 statistics"),
1745 NULL, 0, &ip6stat, sizeof(ip6stat),
1746 CTL_NET, PF_INET6, IPPROTO_IPV6,
1747 IPV6CTL_STATS, CTL_EOL);
1748 sysctl_createv(clog, 0, NULL, NULL,
1749 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1750 CTLTYPE_INT, "use_defaultzone",
1751 SYSCTL_DESCR("Whether to use the default scope zones"),
1752 NULL, 0, &ip6_use_defzone, 0,
1753 CTL_NET, PF_INET6, IPPROTO_IPV6,
1754 IPV6CTL_USE_DEFAULTZONE, CTL_EOL);
1755 sysctl_createv(clog, 0, NULL, NULL,
1756 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1757 CTLTYPE_INT, "mcast_pmtu",
1758 SYSCTL_DESCR("Enable pMTU discovery for multicast packet"),
1759 NULL, 0, &ip6_mcast_pmtu, 0,
1760 CTL_NET, PF_INET6, IPPROTO_IPV6,
1761 CTL_CREATE, CTL_EOL);
1762 }
1763