2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the project nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * $KAME: ip6_input.c,v 1.259 2002/01/21 04:58:09 jinmei Exp $
33 * Copyright (c) 1982, 1986, 1988, 1993
34 * The Regents of the University of California. All rights reserved.
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions
39 * 1. Redistributions of source code must retain the above copyright
40 * notice, this list of conditions and the following disclaimer.
41 * 2. Redistributions in binary form must reproduce the above copyright
42 * notice, this list of conditions and the following disclaimer in the
43 * documentation and/or other materials provided with the distribution.
44 * 4. Neither the name of the University nor the names of its contributors
45 * may be used to endorse or promote products derived from this software
46 * without specific prior written permission.
48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
60 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94
63 #include <sys/cdefs.h>
64 __FBSDID("$FreeBSD$");
67 #include "opt_inet6.h"
68 #include "opt_ipsec.h"
70 #include <sys/param.h>
71 #include <sys/systm.h>
72 #include <sys/malloc.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>
81 #include <sys/kernel.h>
82 #include <sys/syslog.h>
85 #include <net/if_types.h>
86 #include <net/if_dl.h>
87 #include <net/route.h>
88 #include <net/netisr.h>
92 #include <netinet/in.h>
93 #include <netinet/in_systm.h>
94 #include <net/if_llatbl.h>
96 #include <netinet/ip.h>
97 #include <netinet/ip_icmp.h>
99 #include <netinet/ip6.h>
100 #include <netinet6/in6_var.h>
101 #include <netinet6/ip6_var.h>
102 #include <netinet/in_pcb.h>
103 #include <netinet/icmp6.h>
104 #include <netinet6/scope6_var.h>
105 #include <netinet6/in6_ifattach.h>
106 #include <netinet6/nd6.h>
109 #include <netipsec/ipsec.h>
110 #include <netinet6/ip6_ipsec.h>
111 #include <netipsec/ipsec6.h>
114 #include <netinet6/ip6protosw.h>
116 extern struct domain inet6domain;
118 u_char ip6_protox[IPPROTO_MAX];
119 VNET_DEFINE(struct in6_ifaddrhead, in6_ifaddrhead);
121 static struct netisr_handler ip6_nh = {
123 .nh_handler = ip6_input,
124 .nh_proto = NETISR_IPV6,
125 .nh_policy = NETISR_POLICY_FLOW,
128 VNET_DECLARE(struct callout, in6_tmpaddrtimer_ch);
129 #define V_in6_tmpaddrtimer_ch VNET(in6_tmpaddrtimer_ch)
131 VNET_DEFINE(struct pfil_head, inet6_pfil_hook);
133 VNET_DEFINE(struct ip6stat, ip6stat);
135 struct rwlock in6_ifaddr_lock;
136 RW_SYSINIT(in6_ifaddr_lock, &in6_ifaddr_lock, "in6_ifaddr_lock");
138 static void ip6_init2(void *);
139 static struct ip6aux *ip6_setdstifaddr(struct mbuf *, struct in6_ifaddr *);
140 static int ip6_hopopts_input(u_int32_t *, u_int32_t *, struct mbuf **, int *);
142 static struct mbuf *ip6_pullexthdr(struct mbuf *, size_t, int);
146 * IP6 initialization: fill in IP6 protocol switch table.
147 * All protocols not implemented in kernel go to raw IP6 protocol handler.
152 struct ip6protosw *pr;
155 TUNABLE_INT_FETCH("net.inet6.ip6.auto_linklocal",
156 &V_ip6_auto_linklocal);
158 TAILQ_INIT(&V_in6_ifaddrhead);
160 /* Initialize packet filter hooks. */
161 V_inet6_pfil_hook.ph_type = PFIL_TYPE_AF;
162 V_inet6_pfil_hook.ph_af = AF_INET6;
163 if ((i = pfil_head_register(&V_inet6_pfil_hook)) != 0)
164 printf("%s: WARNING: unable to register pfil hook, "
165 "error %d\n", __func__, i);
168 addrsel_policy_init();
172 V_ip6_desync_factor = arc4random() % MAX_TEMP_DESYNC_FACTOR;
174 /* Skip global initialization stuff for non-default instances. */
175 if (!IS_DEFAULT_VNET(curvnet))
179 if (sizeof(struct protosw) != sizeof(struct ip6protosw))
180 panic("sizeof(protosw) != sizeof(ip6protosw)");
182 pr = (struct ip6protosw *)pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW);
186 /* Initialize the entire ip6_protox[] array to IPPROTO_RAW. */
187 for (i = 0; i < IPPROTO_MAX; i++)
188 ip6_protox[i] = pr - inet6sw;
190 * Cycle through IP protocols and put them into the appropriate place
193 for (pr = (struct ip6protosw *)inet6domain.dom_protosw;
194 pr < (struct ip6protosw *)inet6domain.dom_protoswNPROTOSW; pr++)
195 if (pr->pr_domain->dom_family == PF_INET6 &&
196 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) {
197 /* Be careful to only index valid IP protocols. */
198 if (pr->pr_protocol < IPPROTO_MAX)
199 ip6_protox[pr->pr_protocol] = pr - inet6sw;
202 netisr_register(&ip6_nh);
206 * The protocol to be inserted into ip6_protox[] must be already registered
207 * in inet6sw[], either statically or through pf_proto_register().
210 ip6proto_register(short ip6proto)
212 struct ip6protosw *pr;
215 if (ip6proto <= 0 || ip6proto >= IPPROTO_MAX)
216 return (EPROTONOSUPPORT);
219 * The protocol slot must not be occupied by another protocol
220 * already. An index pointing to IPPROTO_RAW is unused.
222 pr = (struct ip6protosw *)pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW);
224 return (EPFNOSUPPORT);
225 if (ip6_protox[ip6proto] != pr - inet6sw) /* IPPROTO_RAW */
229 * Find the protocol position in inet6sw[] and set the index.
231 for (pr = (struct ip6protosw *)inet6domain.dom_protosw;
232 pr < (struct ip6protosw *)inet6domain.dom_protoswNPROTOSW; pr++) {
233 if (pr->pr_domain->dom_family == PF_INET6 &&
234 pr->pr_protocol && pr->pr_protocol == ip6proto) {
235 ip6_protox[pr->pr_protocol] = pr - inet6sw;
239 return (EPROTONOSUPPORT);
243 ip6proto_unregister(short ip6proto)
245 struct ip6protosw *pr;
248 if (ip6proto <= 0 || ip6proto >= IPPROTO_MAX)
249 return (EPROTONOSUPPORT);
251 /* Check if the protocol was indeed registered. */
252 pr = (struct ip6protosw *)pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW);
254 return (EPFNOSUPPORT);
255 if (ip6_protox[ip6proto] == pr - inet6sw) /* IPPROTO_RAW */
258 /* Reset the protocol slot to IPPROTO_RAW. */
259 ip6_protox[ip6proto] = pr - inet6sw;
269 callout_drain(&V_in6_tmpaddrtimer_ch);
274 ip6_init2_vnet(const void *unused __unused)
278 callout_init(&V_nd6_timer_ch, 0);
279 callout_reset(&V_nd6_timer_ch, hz, nd6_timer, curvnet);
281 /* timer for regeneranation of temporary addresses randomize ID */
282 callout_init(&V_in6_tmpaddrtimer_ch, 0);
283 callout_reset(&V_in6_tmpaddrtimer_ch,
284 (V_ip6_temp_preferred_lifetime - V_ip6_desync_factor -
285 V_ip6_temp_regen_advance) * hz,
286 in6_tmpaddrtimer, curvnet);
292 ip6_init2(void *dummy)
295 ip6_init2_vnet(NULL);
299 /* This must be after route_init(), which is now SI_ORDER_THIRD */
300 SYSINIT(netinet6init2, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ip6_init2, NULL);
303 ip6_input(struct mbuf *m)
306 int off = sizeof(struct ip6_hdr), nest;
308 u_int32_t rtalert = ~0;
310 struct ifnet *deliverifp = NULL, *ifp = NULL;
311 struct in6_addr odst;
312 struct route_in6 rin6;
314 struct llentry *lle = NULL;
315 struct sockaddr_in6 dst6, *dst;
317 bzero(&rin6, sizeof(struct route_in6));
320 * should the inner packet be considered authentic?
321 * see comment in ah4_input().
322 * NB: m cannot be NULL when passed to the input routine
325 m->m_flags &= ~M_AUTHIPHDR;
326 m->m_flags &= ~M_AUTHIPDGM;
331 * make sure we don't have onion peering information into m_tag.
338 if (m->m_flags & M_EXT) {
340 V_ip6stat.ip6s_mext2m++;
342 V_ip6stat.ip6s_mext1++;
344 #define M2MMAX (sizeof(V_ip6stat.ip6s_m2m)/sizeof(V_ip6stat.ip6s_m2m[0]))
346 if (m->m_flags & M_LOOP) {
347 V_ip6stat.ip6s_m2m[V_loif->if_index]++;
348 } else if (m->m_pkthdr.rcvif->if_index < M2MMAX)
349 V_ip6stat.ip6s_m2m[m->m_pkthdr.rcvif->if_index]++;
351 V_ip6stat.ip6s_m2m[0]++;
357 /* drop the packet if IPv6 operation is disabled on the IF */
358 if ((ND_IFINFO(m->m_pkthdr.rcvif)->flags & ND6_IFF_IFDISABLED)) {
363 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_receive);
364 V_ip6stat.ip6s_total++;
366 #ifndef PULLDOWN_TEST
368 * L2 bridge code and some other code can return mbuf chain
369 * that does not conform to KAME requirement. too bad.
370 * XXX: fails to join if interface MTU > MCLBYTES. jumbogram?
372 if (m && m->m_next != NULL && m->m_pkthdr.len < MCLBYTES) {
375 MGETHDR(n, M_DONTWAIT, MT_HEADER);
378 if (n && n->m_pkthdr.len > MHLEN) {
379 MCLGET(n, M_DONTWAIT);
380 if ((n->m_flags & M_EXT) == 0) {
387 return; /* ENOBUFS */
390 m_copydata(m, 0, n->m_pkthdr.len, mtod(n, caddr_t));
391 n->m_len = n->m_pkthdr.len;
395 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), /* nothing */);
398 if (m->m_len < sizeof(struct ip6_hdr)) {
400 inifp = m->m_pkthdr.rcvif;
401 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) {
402 V_ip6stat.ip6s_toosmall++;
403 in6_ifstat_inc(inifp, ifs6_in_hdrerr);
408 ip6 = mtod(m, struct ip6_hdr *);
410 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
411 V_ip6stat.ip6s_badvers++;
412 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr);
416 V_ip6stat.ip6s_nxthist[ip6->ip6_nxt]++;
419 * Check against address spoofing/corruption.
421 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) ||
422 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) {
424 * XXX: "badscope" is not very suitable for a multicast source.
426 V_ip6stat.ip6s_badscope++;
427 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
430 if (IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst) &&
431 !(m->m_flags & M_LOOP)) {
433 * In this case, the packet should come from the loopback
434 * interface. However, we cannot just check the if_flags,
435 * because ip6_mloopback() passes the "actual" interface
436 * as the outgoing/incoming interface.
438 V_ip6stat.ip6s_badscope++;
439 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
444 if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) {
445 /* packet is dropped by traffic conditioner */
450 * The following check is not documented in specs. A malicious
451 * party may be able to use IPv4 mapped addr to confuse tcp/udp stack
452 * and bypass security checks (act as if it was from 127.0.0.1 by using
453 * IPv6 src ::ffff:127.0.0.1). Be cautious.
455 * This check chokes if we are in an SIIT cloud. As none of BSDs
456 * support IPv4-less kernel compilation, we cannot support SIIT
457 * environment at all. So, it makes more sense for us to reject any
458 * malicious packets for non-SIIT environment, than try to do a
459 * partial support for SIIT environment.
461 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
462 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
463 V_ip6stat.ip6s_badscope++;
464 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
469 * Reject packets with IPv4 compatible addresses (auto tunnel).
471 * The code forbids auto tunnel relay case in RFC1933 (the check is
472 * stronger than RFC1933). We may want to re-enable it if mech-xx
473 * is revised to forbid relaying case.
475 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) ||
476 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) {
477 V_ip6stat.ip6s_badscope++;
478 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
484 * Run through list of hooks for input packets.
486 * NB: Beware of the destination address changing
487 * (e.g. by NAT rewriting). When this happens,
488 * tell ip6_forward to do the right thing.
492 /* Jump over all PFIL processing if hooks are not active. */
493 if (!PFIL_HOOKED(&V_inet6_pfil_hook))
496 if (pfil_run_hooks(&V_inet6_pfil_hook, &m,
497 m->m_pkthdr.rcvif, PFIL_IN, NULL))
499 if (m == NULL) /* consumed by filter */
501 ip6 = mtod(m, struct ip6_hdr *);
502 srcrt = !IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst);
506 * Disambiguate address scope zones (if there is ambiguity).
507 * We first make sure that the original source or destination address
508 * is not in our internal form for scoped addresses. Such addresses
509 * are not necessarily invalid spec-wise, but we cannot accept them due
510 * to the usage conflict.
511 * in6_setscope() then also checks and rejects the cases where src or
512 * dst are the loopback address and the receiving interface
515 if (in6_clearscope(&ip6->ip6_src) || in6_clearscope(&ip6->ip6_dst)) {
516 V_ip6stat.ip6s_badscope++; /* XXX */
519 if (in6_setscope(&ip6->ip6_src, m->m_pkthdr.rcvif, NULL) ||
520 in6_setscope(&ip6->ip6_dst, m->m_pkthdr.rcvif, NULL)) {
521 V_ip6stat.ip6s_badscope++;
526 * Multicast check. Assume packet is for us to avoid
527 * prematurely taking locks.
529 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
531 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast);
532 deliverifp = m->m_pkthdr.rcvif;
540 bzero(&dst6, sizeof(dst6));
541 dst6.sin6_family = AF_INET6;
542 dst6.sin6_len = sizeof(struct sockaddr_in6);
543 dst6.sin6_addr = ip6->ip6_dst;
544 ifp = m->m_pkthdr.rcvif;
546 lle = lla_lookup(LLTABLE6(ifp), 0,
547 (struct sockaddr *)&dst6);
548 IF_AFDATA_UNLOCK(ifp);
549 if ((lle != NULL) && (lle->la_flags & LLE_IFADDR)) {
551 struct in6_ifaddr *ia6;
555 #define sa_equal(a1, a2) \
556 (bcmp((a1), (a2), ((a1))->sin6_len) == 0)
558 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
559 if (ifa->ifa_addr->sa_family != dst6.sin6_family)
561 if (sa_equal(&dst6, ifa->ifa_addr))
564 KASSERT(ifa != NULL, ("%s: ifa not found for lle %p",
568 ia6 = (struct in6_ifaddr *)ifa;
569 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) {
570 /* Count the packet in the ip address stats */
571 ia6->ia_ifa.if_ipackets++;
572 ia6->ia_ifa.if_ibytes += m->m_pkthdr.len;
575 * record address information into m_tag.
577 (void)ip6_setdstifaddr(m, ia6);
581 char ip6bufs[INET6_ADDRSTRLEN];
582 char ip6bufd[INET6_ADDRSTRLEN];
583 /* address is not ready, so discard the packet. */
585 "ip6_input: packet to an unready address %s->%s\n",
586 ip6_sprintf(ip6bufs, &ip6->ip6_src),
587 ip6_sprintf(ip6bufd, &ip6->ip6_dst)));
603 dst->sin6_len = sizeof(struct sockaddr_in6);
604 dst->sin6_family = AF_INET6;
605 dst->sin6_addr = ip6->ip6_dst;
606 rin6.ro_rt = rtalloc1((struct sockaddr *)dst, 0, 0);
608 RT_UNLOCK(rin6.ro_rt);
610 #define rt6_key(r) ((struct sockaddr_in6 *)((r)->rt_nodes->rn_key))
613 * Accept the packet if the forwarding interface to the destination
614 * according to the routing table is the loopback interface,
615 * unless the associated route has a gateway.
616 * Note that this approach causes to accept a packet if there is a
617 * route to the loopback interface for the destination of the packet.
618 * But we think it's even useful in some situations, e.g. when using
619 * a special daemon which wants to intercept the packet.
621 * XXX: some OSes automatically make a cloned route for the destination
622 * of an outgoing packet. If the outgoing interface of the packet
623 * is a loopback one, the kernel would consider the packet to be
624 * accepted, even if we have no such address assinged on the interface.
625 * We check the cloned flag of the route entry to reject such cases,
626 * assuming that route entries for our own addresses are not made by
627 * cloning (it should be true because in6_addloop explicitly installs
628 * the host route). However, we might have to do an explicit check
629 * while it would be less efficient. Or, should we rather install a
630 * reject route for such a case?
633 (rin6.ro_rt->rt_flags &
634 (RTF_HOST|RTF_GATEWAY)) == RTF_HOST &&
636 !(rin6.ro_rt->rt_flags & RTF_WASCLONED) &&
639 !(rin6.ro_rt->rt_flags & RTF_CLONED) &&
643 * The check below is redundant since the comparison of
644 * the destination and the key of the rtentry has
645 * already done through looking up the routing table.
647 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
648 &rt6_key(rin6.ro_rt)->sin6_addr)
650 rin6.ro_rt->rt_ifp->if_type == IFT_LOOP) {
652 struct in6_ifaddr *ia6;
655 * found the loopback route to the interface address
657 if (rin6.ro_rt->rt_gateway->sa_family == AF_LINK) {
658 struct sockaddr_in6 dest6;
660 bzero(&dest6, sizeof(dest6));
661 dest6.sin6_family = AF_INET6;
662 dest6.sin6_len = sizeof(dest6);
663 dest6.sin6_addr = ip6->ip6_dst;
664 ia6 = (struct in6_ifaddr *)
665 ifa_ifwithaddr((struct sockaddr *)&dest6);
671 ia6 = (struct in6_ifaddr *)rin6.ro_rt->rt_ifa;
674 * record address information into m_tag.
676 (void)ip6_setdstifaddr(m, ia6);
679 * packets to a tentative, duplicated, or somehow invalid
680 * address must not be accepted.
682 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) {
683 /* this address is ready */
685 deliverifp = ia6->ia_ifp; /* correct? */
686 /* Count the packet in the ip address stats */
687 ia6->ia_ifa.if_ipackets++;
688 ia6->ia_ifa.if_ibytes += m->m_pkthdr.len;
689 if (ia6 != NULL && free_ia6 != 0)
690 ifa_free(&ia6->ia_ifa);
693 char ip6bufs[INET6_ADDRSTRLEN];
694 char ip6bufd[INET6_ADDRSTRLEN];
695 /* address is not ready, so discard the packet. */
697 "ip6_input: packet to an unready address %s->%s\n",
698 ip6_sprintf(ip6bufs, &ip6->ip6_src),
699 ip6_sprintf(ip6bufd, &ip6->ip6_dst)));
701 if (ia6 != NULL && free_ia6 != 0)
702 ifa_free(&ia6->ia_ifa);
708 * FAITH (Firewall Aided Internet Translator)
710 if (V_ip6_keepfaith) {
711 if (rin6.ro_rt && rin6.ro_rt->rt_ifp &&
712 rin6.ro_rt->rt_ifp->if_type == IFT_FAITH) {
713 /* XXX do we need more sanity checks? */
715 deliverifp = rin6.ro_rt->rt_ifp; /* faith */
721 * Now there is no reason to process the packet if it's not our own
722 * and we're not a router.
724 if (!V_ip6_forwarding) {
725 V_ip6stat.ip6s_cantforward++;
726 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
732 * record address information into m_tag, if we don't have one yet.
733 * note that we are unable to record it, if the address is not listed
734 * as our interface address (e.g. multicast addresses, addresses
735 * within FAITH prefixes and such).
737 if (deliverifp && !ip6_getdstifaddr(m)) {
738 struct in6_ifaddr *ia6;
740 ia6 = in6_ifawithifp(deliverifp, &ip6->ip6_dst);
742 if (!ip6_setdstifaddr(m, ia6)) {
744 * XXX maybe we should drop the packet here,
745 * as we could not provide enough information
746 * to the upper layers.
749 ifa_free(&ia6->ia_ifa);
754 * Process Hop-by-Hop options header if it's contained.
755 * m may be modified in ip6_hopopts_input().
756 * If a JumboPayload option is included, plen will also be modified.
758 plen = (u_int32_t)ntohs(ip6->ip6_plen);
759 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) {
762 if (ip6_hopopts_input(&plen, &rtalert, &m, &off)) {
763 #if 0 /*touches NULL pointer*/
764 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
766 goto out; /* m have already been freed */
770 ip6 = mtod(m, struct ip6_hdr *);
773 * if the payload length field is 0 and the next header field
774 * indicates Hop-by-Hop Options header, then a Jumbo Payload
775 * option MUST be included.
777 if (ip6->ip6_plen == 0 && plen == 0) {
779 * Note that if a valid jumbo payload option is
780 * contained, ip6_hopopts_input() must set a valid
781 * (non-zero) payload length to the variable plen.
783 V_ip6stat.ip6s_badoptions++;
784 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
785 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr);
786 icmp6_error(m, ICMP6_PARAM_PROB,
787 ICMP6_PARAMPROB_HEADER,
788 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6);
791 #ifndef PULLDOWN_TEST
792 /* ip6_hopopts_input() ensures that mbuf is contiguous */
793 hbh = (struct ip6_hbh *)(ip6 + 1);
795 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr),
796 sizeof(struct ip6_hbh));
798 V_ip6stat.ip6s_tooshort++;
805 * If we are acting as a router and the packet contains a
806 * router alert option, see if we know the option value.
807 * Currently, we only support the option value for MLD, in which
808 * case we should pass the packet to the multicast routing
813 case IP6OPT_RTALERT_MLD:
814 if (V_ip6_forwarding)
819 * RFC2711 requires unrecognized values must be
829 * Check that the amount of data in the buffers
830 * is as at least much as the IPv6 header would have us expect.
831 * Trim mbufs if longer than we expect.
832 * Drop packet if shorter than we expect.
834 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) {
835 V_ip6stat.ip6s_tooshort++;
836 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);
839 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) {
840 if (m->m_len == m->m_pkthdr.len) {
841 m->m_len = sizeof(struct ip6_hdr) + plen;
842 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen;
844 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len);
848 * Forward if desirable.
851 IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
853 * If we are acting as a multicast router, all
854 * incoming multicast packets are passed to the
855 * kernel-level multicast forwarding function.
856 * The packet is returned (relatively) intact; if
857 * ip6_mforward() returns a non-zero value, the packet
858 * must be discarded, else it may be accepted below.
860 * XXX TODO: Check hlim and multicast scope here to avoid
861 * unnecessarily calling into ip6_mforward().
864 ip6_mforward(ip6, m->m_pkthdr.rcvif, m)) {
865 IP6STAT_INC(ip6s_cantforward);
866 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
870 ip6_forward(m, srcrt);
874 ip6 = mtod(m, struct ip6_hdr *);
877 * Malicious party may be able to use IPv4 mapped addr to confuse
878 * tcp/udp stack and bypass security checks (act as if it was from
879 * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious.
881 * For SIIT end node behavior, you may want to disable the check.
882 * However, you will become vulnerable to attacks using IPv4 mapped
885 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
886 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
887 V_ip6stat.ip6s_badscope++;
888 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
893 * Tell launch routine the next header
895 V_ip6stat.ip6s_delivered++;
896 in6_ifstat_inc(deliverifp, ifs6_in_deliver);
899 while (nxt != IPPROTO_DONE) {
900 if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) {
901 V_ip6stat.ip6s_toomanyhdr++;
906 * protection against faulty packet - there should be
907 * more sanity checks in header chain processing.
909 if (m->m_pkthdr.len < off) {
910 V_ip6stat.ip6s_tooshort++;
911 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);
917 * enforce IPsec policy checking if we are seeing last header.
918 * note that we do not visit this with protocols with pcb layer
919 * code - like udp/tcp/raw ip.
921 if (ip6_ipsec_input(m, nxt))
926 * Use mbuf flags to propagate Router Alert option to
927 * ICMPv6 layer, as hop-by-hop options have been stripped.
929 if (nxt == IPPROTO_ICMPV6 && rtalert != ~0)
930 m->m_flags |= M_RTALERT_MLD;
932 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt);
943 * set/grab in6_ifaddr correspond to IPv6 destination address.
944 * XXX backward compatibility wrapper
946 * XXXRW: We should bump the refcount on ia6 before sticking it in the m_tag,
947 * and then bump it when the tag is copied, and release it when the tag is
948 * freed. Unfortunately, m_tags don't support deep copies (yet), so instead
949 * we just bump the ia refcount when we receive it. This should be fixed.
951 static struct ip6aux *
952 ip6_setdstifaddr(struct mbuf *m, struct in6_ifaddr *ia6)
956 ip6a = ip6_addaux(m);
958 ip6a->ip6a_dstia6 = ia6;
959 return ip6a; /* NULL if failed to set */
963 ip6_getdstifaddr(struct mbuf *m)
966 struct in6_ifaddr *ia;
968 ip6a = ip6_findaux(m);
970 ia = ip6a->ip6a_dstia6;
971 ifa_ref(&ia->ia_ifa);
978 * Hop-by-Hop options header processing. If a valid jumbo payload option is
979 * included, the real payload length will be stored in plenp.
981 * rtalertp - XXX: should be stored more smart way
984 ip6_hopopts_input(u_int32_t *plenp, u_int32_t *rtalertp,
985 struct mbuf **mp, int *offp)
987 struct mbuf *m = *mp;
988 int off = *offp, hbhlen;
992 /* validation of the length of the header */
993 #ifndef PULLDOWN_TEST
994 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1);
995 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off);
996 hbhlen = (hbh->ip6h_len + 1) << 3;
998 IP6_EXTHDR_CHECK(m, off, hbhlen, -1);
999 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off);
1001 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m,
1002 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh));
1004 V_ip6stat.ip6s_tooshort++;
1007 hbhlen = (hbh->ip6h_len + 1) << 3;
1008 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr),
1011 V_ip6stat.ip6s_tooshort++;
1016 hbhlen -= sizeof(struct ip6_hbh);
1017 opt = (u_int8_t *)hbh + sizeof(struct ip6_hbh);
1019 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh),
1020 hbhlen, rtalertp, plenp) < 0)
1029 * Search header for all Hop-by-hop options and process each option.
1030 * This function is separate from ip6_hopopts_input() in order to
1031 * handle a case where the sending node itself process its hop-by-hop
1032 * options header. In such a case, the function is called from ip6_output().
1034 * The function assumes that hbh header is located right after the IPv6 header
1035 * (RFC2460 p7), opthead is pointer into data content in m, and opthead to
1036 * opthead + hbhlen is located in continuous memory region.
1039 ip6_process_hopopts(struct mbuf *m, u_int8_t *opthead, int hbhlen,
1040 u_int32_t *rtalertp, u_int32_t *plenp)
1042 struct ip6_hdr *ip6;
1044 u_int8_t *opt = opthead;
1045 u_int16_t rtalert_val;
1046 u_int32_t jumboplen;
1047 const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh);
1049 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) {
1055 if (hbhlen < IP6OPT_MINLEN) {
1056 V_ip6stat.ip6s_toosmall++;
1059 optlen = *(opt + 1) + 2;
1061 case IP6OPT_ROUTER_ALERT:
1062 /* XXX may need check for alignment */
1063 if (hbhlen < IP6OPT_RTALERT_LEN) {
1064 V_ip6stat.ip6s_toosmall++;
1067 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) {
1069 icmp6_error(m, ICMP6_PARAM_PROB,
1070 ICMP6_PARAMPROB_HEADER,
1071 erroff + opt + 1 - opthead);
1074 optlen = IP6OPT_RTALERT_LEN;
1075 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2);
1076 *rtalertp = ntohs(rtalert_val);
1079 /* XXX may need check for alignment */
1080 if (hbhlen < IP6OPT_JUMBO_LEN) {
1081 V_ip6stat.ip6s_toosmall++;
1084 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) {
1086 icmp6_error(m, ICMP6_PARAM_PROB,
1087 ICMP6_PARAMPROB_HEADER,
1088 erroff + opt + 1 - opthead);
1091 optlen = IP6OPT_JUMBO_LEN;
1094 * IPv6 packets that have non 0 payload length
1095 * must not contain a jumbo payload option.
1097 ip6 = mtod(m, struct ip6_hdr *);
1098 if (ip6->ip6_plen) {
1099 V_ip6stat.ip6s_badoptions++;
1100 icmp6_error(m, ICMP6_PARAM_PROB,
1101 ICMP6_PARAMPROB_HEADER,
1102 erroff + opt - opthead);
1107 * We may see jumbolen in unaligned location, so
1108 * we'd need to perform bcopy().
1110 bcopy(opt + 2, &jumboplen, sizeof(jumboplen));
1111 jumboplen = (u_int32_t)htonl(jumboplen);
1115 * if there are multiple jumbo payload options,
1116 * *plenp will be non-zero and the packet will be
1118 * the behavior may need some debate in ipngwg -
1119 * multiple options does not make sense, however,
1120 * there's no explicit mention in specification.
1123 V_ip6stat.ip6s_badoptions++;
1124 icmp6_error(m, ICMP6_PARAM_PROB,
1125 ICMP6_PARAMPROB_HEADER,
1126 erroff + opt + 2 - opthead);
1132 * jumbo payload length must be larger than 65535.
1134 if (jumboplen <= IPV6_MAXPACKET) {
1135 V_ip6stat.ip6s_badoptions++;
1136 icmp6_error(m, ICMP6_PARAM_PROB,
1137 ICMP6_PARAMPROB_HEADER,
1138 erroff + opt + 2 - opthead);
1144 default: /* unknown option */
1145 if (hbhlen < IP6OPT_MINLEN) {
1146 V_ip6stat.ip6s_toosmall++;
1149 optlen = ip6_unknown_opt(opt, m,
1150 erroff + opt - opthead);
1166 * Unknown option processing.
1167 * The third argument `off' is the offset from the IPv6 header to the option,
1168 * which is necessary if the IPv6 header the and option header and IPv6 header
1169 * is not continuous in order to return an ICMPv6 error.
1172 ip6_unknown_opt(u_int8_t *optp, struct mbuf *m, int off)
1174 struct ip6_hdr *ip6;
1176 switch (IP6OPT_TYPE(*optp)) {
1177 case IP6OPT_TYPE_SKIP: /* ignore the option */
1178 return ((int)*(optp + 1));
1179 case IP6OPT_TYPE_DISCARD: /* silently discard */
1182 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */
1183 V_ip6stat.ip6s_badoptions++;
1184 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off);
1186 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */
1187 V_ip6stat.ip6s_badoptions++;
1188 ip6 = mtod(m, struct ip6_hdr *);
1189 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) ||
1190 (m->m_flags & (M_BCAST|M_MCAST)))
1193 icmp6_error(m, ICMP6_PARAM_PROB,
1194 ICMP6_PARAMPROB_OPTION, off);
1198 m_freem(m); /* XXX: NOTREACHED */
1203 * Create the "control" list for this pcb.
1204 * These functions will not modify mbuf chain at all.
1206 * With KAME mbuf chain restriction:
1207 * The routine will be called from upper layer handlers like tcp6_input().
1208 * Thus the routine assumes that the caller (tcp6_input) have already
1209 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the
1210 * very first mbuf on the mbuf chain.
1212 * ip6_savecontrol_v4 will handle those options that are possible to be
1213 * set on a v4-mapped socket.
1214 * ip6_savecontrol will directly call ip6_savecontrol_v4 to handle those
1215 * options and handle the v6-only ones itself.
1218 ip6_savecontrol_v4(struct inpcb *inp, struct mbuf *m, struct mbuf **mp,
1221 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1224 if ((inp->inp_socket->so_options & SO_TIMESTAMP) != 0) {
1228 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv),
1229 SCM_TIMESTAMP, SOL_SOCKET);
1231 mp = &(*mp)->m_next;
1235 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
1241 #define IS2292(inp, x, y) (((inp)->inp_flags & IN6P_RFC2292) ? (x) : (y))
1242 /* RFC 2292 sec. 5 */
1243 if ((inp->inp_flags & IN6P_PKTINFO) != 0) {
1244 struct in6_pktinfo pi6;
1246 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr));
1247 in6_clearscope(&pi6.ipi6_addr); /* XXX */
1249 (m && m->m_pkthdr.rcvif) ? m->m_pkthdr.rcvif->if_index : 0;
1251 *mp = sbcreatecontrol((caddr_t) &pi6,
1252 sizeof(struct in6_pktinfo),
1253 IS2292(inp, IPV6_2292PKTINFO, IPV6_PKTINFO), IPPROTO_IPV6);
1255 mp = &(*mp)->m_next;
1258 if ((inp->inp_flags & IN6P_HOPLIMIT) != 0) {
1259 int hlim = ip6->ip6_hlim & 0xff;
1261 *mp = sbcreatecontrol((caddr_t) &hlim, sizeof(int),
1262 IS2292(inp, IPV6_2292HOPLIMIT, IPV6_HOPLIMIT),
1265 mp = &(*mp)->m_next;
1274 ip6_savecontrol(struct inpcb *in6p, struct mbuf *m, struct mbuf **mp)
1276 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1279 mp = ip6_savecontrol_v4(in6p, m, mp, &v4only);
1283 if ((in6p->inp_flags & IN6P_TCLASS) != 0) {
1287 flowinfo = (u_int32_t)ntohl(ip6->ip6_flow & IPV6_FLOWINFO_MASK);
1290 tclass = flowinfo & 0xff;
1291 *mp = sbcreatecontrol((caddr_t) &tclass, sizeof(tclass),
1292 IPV6_TCLASS, IPPROTO_IPV6);
1294 mp = &(*mp)->m_next;
1298 * IPV6_HOPOPTS socket option. Recall that we required super-user
1299 * privilege for the option (see ip6_ctloutput), but it might be too
1300 * strict, since there might be some hop-by-hop options which can be
1301 * returned to normal user.
1302 * See also RFC 2292 section 6 (or RFC 3542 section 8).
1304 if ((in6p->inp_flags & IN6P_HOPOPTS) != 0) {
1306 * Check if a hop-by-hop options header is contatined in the
1307 * received packet, and if so, store the options as ancillary
1308 * data. Note that a hop-by-hop options header must be
1309 * just after the IPv6 header, which is assured through the
1310 * IPv6 input processing.
1312 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) {
1313 struct ip6_hbh *hbh;
1315 #ifdef PULLDOWN_TEST
1319 #ifndef PULLDOWN_TEST
1320 hbh = (struct ip6_hbh *)(ip6 + 1);
1321 hbhlen = (hbh->ip6h_len + 1) << 3;
1323 ext = ip6_pullexthdr(m, sizeof(struct ip6_hdr),
1326 V_ip6stat.ip6s_tooshort++;
1329 hbh = mtod(ext, struct ip6_hbh *);
1330 hbhlen = (hbh->ip6h_len + 1) << 3;
1331 if (hbhlen != ext->m_len) {
1333 V_ip6stat.ip6s_tooshort++;
1339 * XXX: We copy the whole header even if a
1340 * jumbo payload option is included, the option which
1341 * is to be removed before returning according to
1343 * Note: this constraint is removed in RFC3542
1345 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen,
1346 IS2292(in6p, IPV6_2292HOPOPTS, IPV6_HOPOPTS),
1349 mp = &(*mp)->m_next;
1350 #ifdef PULLDOWN_TEST
1356 if ((in6p->inp_flags & (IN6P_RTHDR | IN6P_DSTOPTS)) != 0) {
1357 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr);
1360 * Search for destination options headers or routing
1361 * header(s) through the header chain, and stores each
1362 * header as ancillary data.
1363 * Note that the order of the headers remains in
1364 * the chain of ancillary data.
1366 while (1) { /* is explicit loop prevention necessary? */
1367 struct ip6_ext *ip6e = NULL;
1369 #ifdef PULLDOWN_TEST
1370 struct mbuf *ext = NULL;
1374 * if it is not an extension header, don't try to
1375 * pull it from the chain.
1378 case IPPROTO_DSTOPTS:
1379 case IPPROTO_ROUTING:
1380 case IPPROTO_HOPOPTS:
1381 case IPPROTO_AH: /* is it possible? */
1387 #ifndef PULLDOWN_TEST
1388 if (off + sizeof(*ip6e) > m->m_len)
1390 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off);
1391 if (nxt == IPPROTO_AH)
1392 elen = (ip6e->ip6e_len + 2) << 2;
1394 elen = (ip6e->ip6e_len + 1) << 3;
1395 if (off + elen > m->m_len)
1398 ext = ip6_pullexthdr(m, off, nxt);
1400 V_ip6stat.ip6s_tooshort++;
1403 ip6e = mtod(ext, struct ip6_ext *);
1404 if (nxt == IPPROTO_AH)
1405 elen = (ip6e->ip6e_len + 2) << 2;
1407 elen = (ip6e->ip6e_len + 1) << 3;
1408 if (elen != ext->m_len) {
1410 V_ip6stat.ip6s_tooshort++;
1416 case IPPROTO_DSTOPTS:
1417 if (!(in6p->inp_flags & IN6P_DSTOPTS))
1420 *mp = sbcreatecontrol((caddr_t)ip6e, elen,
1422 IPV6_2292DSTOPTS, IPV6_DSTOPTS),
1425 mp = &(*mp)->m_next;
1427 case IPPROTO_ROUTING:
1428 if (!in6p->inp_flags & IN6P_RTHDR)
1431 *mp = sbcreatecontrol((caddr_t)ip6e, elen,
1432 IS2292(in6p, IPV6_2292RTHDR, IPV6_RTHDR),
1435 mp = &(*mp)->m_next;
1437 case IPPROTO_HOPOPTS:
1438 case IPPROTO_AH: /* is it possible? */
1443 * other cases have been filtered in the above.
1444 * none will visit this case. here we supply
1445 * the code just in case (nxt overwritten or
1448 #ifdef PULLDOWN_TEST
1455 /* proceed with the next header. */
1457 nxt = ip6e->ip6e_nxt;
1459 #ifdef PULLDOWN_TEST
1471 ip6_notify_pmtu(struct inpcb *in6p, struct sockaddr_in6 *dst, u_int32_t *mtu)
1475 struct ip6_mtuinfo mtuctl;
1477 so = in6p->inp_socket;
1483 if (so == NULL) /* I believe this is impossible */
1484 panic("ip6_notify_pmtu: socket is NULL");
1487 bzero(&mtuctl, sizeof(mtuctl)); /* zero-clear for safety */
1488 mtuctl.ip6m_mtu = *mtu;
1489 mtuctl.ip6m_addr = *dst;
1490 if (sa6_recoverscope(&mtuctl.ip6m_addr))
1493 if ((m_mtu = sbcreatecontrol((caddr_t)&mtuctl, sizeof(mtuctl),
1494 IPV6_PATHMTU, IPPROTO_IPV6)) == NULL)
1497 if (sbappendaddr(&so->so_rcv, (struct sockaddr *)dst, NULL, m_mtu)
1500 /* XXX: should count statistics */
1507 #ifdef PULLDOWN_TEST
1509 * pull single extension header from mbuf chain. returns single mbuf that
1510 * contains the result, or NULL on error.
1512 static struct mbuf *
1513 ip6_pullexthdr(struct mbuf *m, size_t off, int nxt)
1515 struct ip6_ext ip6e;
1521 case IPPROTO_DSTOPTS:
1522 case IPPROTO_ROUTING:
1523 case IPPROTO_HOPOPTS:
1524 case IPPROTO_AH: /* is it possible? */
1527 printf("ip6_pullexthdr: invalid nxt=%d\n", nxt);
1531 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
1532 if (nxt == IPPROTO_AH)
1533 elen = (ip6e.ip6e_len + 2) << 2;
1535 elen = (ip6e.ip6e_len + 1) << 3;
1537 MGET(n, M_DONTWAIT, MT_DATA);
1538 if (n && elen >= MLEN) {
1539 MCLGET(n, M_DONTWAIT);
1540 if ((n->m_flags & M_EXT) == 0) {
1549 if (elen >= M_TRAILINGSPACE(n)) {
1554 m_copydata(m, off, elen, mtod(n, caddr_t));
1561 * Get pointer to the previous header followed by the header
1562 * currently processed.
1563 * XXX: This function supposes that
1564 * M includes all headers,
1565 * the next header field and the header length field of each header
1567 * the sum of each header length equals to OFF.
1568 * Because of these assumptions, this function must be called very
1569 * carefully. Moreover, it will not be used in the near future when
1570 * we develop `neater' mechanism to process extension headers.
1573 ip6_get_prevhdr(struct mbuf *m, int off)
1575 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1577 if (off == sizeof(struct ip6_hdr))
1578 return (&ip6->ip6_nxt);
1581 struct ip6_ext *ip6e = NULL;
1584 len = sizeof(struct ip6_hdr);
1586 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len);
1589 case IPPROTO_FRAGMENT:
1590 len += sizeof(struct ip6_frag);
1593 len += (ip6e->ip6e_len + 2) << 2;
1596 len += (ip6e->ip6e_len + 1) << 3;
1599 nxt = ip6e->ip6e_nxt;
1602 return (&ip6e->ip6e_nxt);
1609 * get next header offset. m will be retained.
1612 ip6_nexthdr(struct mbuf *m, int off, int proto, int *nxtp)
1615 struct ip6_ext ip6e;
1620 panic("ip6_nexthdr: m == NULL");
1621 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off)
1626 if (m->m_pkthdr.len < off + sizeof(ip6))
1628 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6);
1630 *nxtp = ip6.ip6_nxt;
1634 case IPPROTO_FRAGMENT:
1636 * terminate parsing if it is not the first fragment,
1637 * it does not make sense to parse through it.
1639 if (m->m_pkthdr.len < off + sizeof(fh))
1641 m_copydata(m, off, sizeof(fh), (caddr_t)&fh);
1642 /* IP6F_OFF_MASK = 0xfff8(BigEndian), 0xf8ff(LittleEndian) */
1643 if (fh.ip6f_offlg & IP6F_OFF_MASK)
1646 *nxtp = fh.ip6f_nxt;
1647 off += sizeof(struct ip6_frag);
1651 if (m->m_pkthdr.len < off + sizeof(ip6e))
1653 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
1655 *nxtp = ip6e.ip6e_nxt;
1656 off += (ip6e.ip6e_len + 2) << 2;
1659 case IPPROTO_HOPOPTS:
1660 case IPPROTO_ROUTING:
1661 case IPPROTO_DSTOPTS:
1662 if (m->m_pkthdr.len < off + sizeof(ip6e))
1664 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
1666 *nxtp = ip6e.ip6e_nxt;
1667 off += (ip6e.ip6e_len + 1) << 3;
1672 case IPPROTO_IPCOMP:
1684 * get offset for the last header in the chain. m will be kept untainted.
1687 ip6_lasthdr(struct mbuf *m, int off, int proto, int *nxtp)
1697 newoff = ip6_nexthdr(m, off, proto, nxtp);
1700 else if (newoff < off)
1701 return -1; /* invalid */
1702 else if (newoff == off)
1711 ip6_addaux(struct mbuf *m)
1715 mtag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL);
1717 mtag = m_tag_get(PACKET_TAG_IPV6_INPUT, sizeof(struct ip6aux),
1720 m_tag_prepend(m, mtag);
1721 bzero(mtag + 1, sizeof(struct ip6aux));
1724 return mtag ? (struct ip6aux *)(mtag + 1) : NULL;
1728 ip6_findaux(struct mbuf *m)
1732 mtag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL);
1733 return mtag ? (struct ip6aux *)(mtag + 1) : NULL;
1737 ip6_delaux(struct mbuf *m)
1741 mtag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL);
1743 m_tag_delete(m, mtag);
1747 * System control for IP6
1750 u_char inet6ctlerrmap[PRC_NCMDS] = {
1752 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH,
1753 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED,
1754 EMSGSIZE, EHOSTUNREACH, 0, 0,