1 /* $FreeBSD: src/sys/netinet6/ip6_input.c,v 1.11.2.15 2003/01/24 05:11:35 sam Exp $ */
2 /* $DragonFly: src/sys/netinet6/ip6_input.c,v 1.38 2008/09/24 14:26:39 sephe Exp $ */
3 /* $KAME: ip6_input.c,v 1.259 2002/01/21 04:58:09 jinmei Exp $ */
6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
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56 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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66 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94
69 #include "opt_ip6fw.h"
71 #include "opt_inet6.h"
72 #include "opt_ipsec.h"
74 #include <sys/param.h>
75 #include <sys/systm.h>
76 #include <sys/malloc.h>
78 #include <sys/domain.h>
79 #include <sys/protosw.h>
80 #include <sys/socket.h>
81 #include <sys/socketvar.h>
82 #include <sys/errno.h>
84 #include <sys/kernel.h>
85 #include <sys/syslog.h>
90 #include <net/if_types.h>
91 #include <net/if_dl.h>
92 #include <net/route.h>
93 #include <net/netisr.h>
96 #include <sys/thread2.h>
97 #include <sys/msgport2.h>
98 #include <net/netmsg2.h>
100 #include <netinet/in.h>
101 #include <netinet/in_systm.h>
103 #include <netinet/ip.h>
104 #include <netinet/ip_icmp.h>
106 #include <netinet/ip6.h>
107 #include <netinet6/in6_var.h>
108 #include <netinet6/ip6_var.h>
109 #include <netinet/in_pcb.h>
110 #include <netinet/icmp6.h>
111 #include <netinet6/scope6_var.h>
112 #include <netinet6/in6_ifattach.h>
113 #include <netinet6/nd6.h>
114 #include <netinet6/in6_prefix.h>
117 #include <netinet6/ipsec.h>
119 #include <netinet6/ipsec6.h>
124 #include <netproto/ipsec/ipsec.h>
125 #include <netproto/ipsec/ipsec6.h>
127 #endif /* FAST_IPSEC */
129 #include <net/ip6fw/ip6_fw.h>
131 #include <netinet6/ip6protosw.h>
133 /* we need it for NLOOP. */
134 #include "use_loop.h"
136 #include <net/net_osdep.h>
138 extern struct domain inet6domain;
139 extern struct ip6protosw inet6sw[];
141 u_char ip6_protox[IPPROTO_MAX];
142 struct in6_ifaddr *in6_ifaddr;
144 extern struct callout in6_tmpaddrtimer_ch;
146 int ip6_forward_srcrt; /* XXX */
147 int ip6_sourcecheck; /* XXX */
148 int ip6_sourcecheck_interval; /* XXX */
150 int ip6_ours_check_algorithm;
152 struct pfil_head inet6_pfil_hook;
155 ip6_fw_chk_t *ip6_fw_chk_ptr;
156 ip6_fw_ctl_t *ip6_fw_ctl_ptr;
157 int ip6_fw_enable = 1;
159 struct ip6stat ip6stat;
161 static void ip6_init2 (void *);
162 static struct ip6aux *ip6_setdstifaddr (struct mbuf *, struct in6_ifaddr *);
163 static int ip6_hopopts_input (u_int32_t *, u_int32_t *, struct mbuf **, int *);
164 static void ip6_input(struct netmsg *msg);
166 static struct mbuf *ip6_pullexthdr (struct mbuf *, size_t, int);
168 static void transport6_processing_handler(netmsg_t netmsg);
171 * IP6 initialization: fill in IP6 protocol switch table.
172 * All protocols not implemented in kernel go to raw IP6 protocol handler.
177 struct ip6protosw *pr;
182 if (sizeof(struct protosw) != sizeof(struct ip6protosw))
183 panic("sizeof(protosw) != sizeof(ip6protosw)");
185 pr = (struct ip6protosw *)pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW);
188 for (i = 0; i < IPPROTO_MAX; i++)
189 ip6_protox[i] = pr - inet6sw;
190 for (pr = (struct ip6protosw *)inet6domain.dom_protosw;
191 pr < (struct ip6protosw *)inet6domain.dom_protoswNPROTOSW; pr++)
192 if (pr->pr_domain->dom_family == PF_INET6 &&
193 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW)
194 ip6_protox[pr->pr_protocol] = pr - inet6sw;
196 inet6_pfil_hook.ph_type = PFIL_TYPE_AF;
197 inet6_pfil_hook.ph_af = AF_INET6;
198 if ((i = pfil_head_register(&inet6_pfil_hook)) != 0) {
199 kprintf("%s: WARNING: unable to register pfil hook, "
200 "error %d\n", __func__, i);
203 netisr_register(NETISR_IPV6, ip6_input, NULL); /* XXX cpufn */
205 addrsel_policy_init();
209 * in many cases, random() here does NOT return random number
210 * as initialization during bootstrap time occur in fixed order.
213 ip6_flow_seq = krandom() ^ tv.tv_usec;
215 ip6_desync_factor = (krandom() ^ tv.tv_usec) % MAX_TEMP_DESYNC_FACTOR;
219 ip6_init2(void *dummy)
222 callout_init(&nd6_timer_ch);
223 callout_reset(&nd6_timer_ch, hz, nd6_timer, NULL);
225 /* router renumbering prefix list maintenance */
226 callout_init(&in6_rr_timer_ch);
227 callout_reset(&in6_rr_timer_ch, hz, in6_rr_timer, NULL);
229 /* timer for regeneranation of temporary addresses randomize ID */
230 callout_init(&in6_tmpaddrtimer_ch);
231 callout_reset(&in6_tmpaddrtimer_ch,
232 (ip6_temp_preferred_lifetime - ip6_desync_factor -
233 ip6_temp_regen_advance) * hz,
234 in6_tmpaddrtimer, NULL);
238 /* This must be after route_init(), which is now SI_ORDER_THIRD */
239 SYSINIT(netinet6init2, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ip6_init2, NULL);
241 extern struct route_in6 ip6_forward_rt;
245 ip6_input(struct netmsg *msg)
247 struct mbuf *m = ((struct netmsg_packet *)msg)->nm_packet;
249 int off = sizeof(struct ip6_hdr), nest;
251 u_int32_t rtalert = ~0;
252 int nxt, ours = 0, rh_present = 0;
253 struct ifnet *deliverifp = NULL;
254 struct in6_addr odst;
259 * should the inner packet be considered authentic?
260 * see comment in ah4_input().
263 m->m_flags &= ~M_AUTHIPHDR;
264 m->m_flags &= ~M_AUTHIPDGM;
269 * make sure we don't have onion peering information into m_aux.
276 if (m->m_flags & M_EXT) {
278 ip6stat.ip6s_mext2m++;
280 ip6stat.ip6s_mext1++;
282 #define M2MMAX (sizeof(ip6stat.ip6s_m2m)/sizeof(ip6stat.ip6s_m2m[0]))
284 if (m->m_flags & M_LOOP) {
285 ip6stat.ip6s_m2m[loif[0].if_index]++; /* XXX */
286 } else if (m->m_pkthdr.rcvif->if_index < M2MMAX)
287 ip6stat.ip6s_m2m[m->m_pkthdr.rcvif->if_index]++;
289 ip6stat.ip6s_m2m[0]++;
295 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_receive);
296 ip6stat.ip6s_total++;
298 #ifndef PULLDOWN_TEST
300 * L2 bridge code and some other code can return mbuf chain
301 * that does not conform to KAME requirement. too bad.
302 * XXX: fails to join if interface MTU > MCLBYTES. jumbogram?
304 if (m && m->m_next != NULL && m->m_pkthdr.len < MCLBYTES) {
307 n = m_getb(m->m_pkthdr.len, MB_DONTWAIT, MT_HEADER, M_PKTHDR);
312 m_copydata(m, 0, n->m_pkthdr.len, mtod(n, caddr_t));
313 n->m_len = n->m_pkthdr.len;
317 IP6_EXTHDR_CHECK_VOIDRET(m, 0, sizeof(struct ip6_hdr));
320 if (m->m_len < sizeof(struct ip6_hdr)) {
322 inifp = m->m_pkthdr.rcvif;
323 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == 0) {
324 ip6stat.ip6s_toosmall++;
325 in6_ifstat_inc(inifp, ifs6_in_hdrerr);
330 ip6 = mtod(m, struct ip6_hdr *);
332 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
333 ip6stat.ip6s_badvers++;
334 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr);
339 * Run through list of hooks for input packets.
341 * NB: Beware of the destination address changing
342 * (e.g. by NAT rewriting). When this happens,
343 * tell ip6_forward to do the right thing.
345 if (pfil_has_hooks(&inet6_pfil_hook)) {
347 if (pfil_run_hooks(&inet6_pfil_hook, &m,
348 m->m_pkthdr.rcvif, PFIL_IN)) {
351 if (m == NULL) /* consumed by filter */
353 ip6 = mtod(m, struct ip6_hdr *);
354 srcrt = !IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst);
357 ip6stat.ip6s_nxthist[ip6->ip6_nxt]++;
360 if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) {
361 /* packet is dropped by traffic conditioner */
367 * Check with the firewall...
369 if (ip6_fw_enable && ip6_fw_chk_ptr) {
371 /* If ipfw says divert, we have to just drop packet */
372 /* use port as a dummy argument */
373 if ((*ip6_fw_chk_ptr)(&ip6, NULL, &port, &m)) {
382 * Check against address spoofing/corruption.
384 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) ||
385 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) {
387 * XXX: "badscope" is not very suitable for a multicast source.
389 ip6stat.ip6s_badscope++;
390 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
393 if ((IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) ||
394 IN6_IS_ADDR_LOOPBACK(&ip6->ip6_dst)) &&
395 (m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) {
396 ip6stat.ip6s_badscope++;
397 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
402 * The following check is not documented in specs. A malicious
403 * party may be able to use IPv4 mapped addr to confuse tcp/udp stack
404 * and bypass security checks (act as if it was from 127.0.0.1 by using
405 * IPv6 src ::ffff:127.0.0.1). Be cautious.
407 * This check chokes if we are in an SIIT cloud. As none of BSDs
408 * support IPv4-less kernel compilation, we cannot support SIIT
409 * environment at all. So, it makes more sense for us to reject any
410 * malicious packets for non-SIIT environment, than try to do a
411 * partical support for SIIT environment.
413 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
414 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
415 ip6stat.ip6s_badscope++;
416 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
421 * Reject packets with IPv4 compatible addresses (auto tunnel).
423 * The code forbids auto tunnel relay case in RFC1933 (the check is
424 * stronger than RFC1933). We may want to re-enable it if mech-xx
425 * is revised to forbid relaying case.
427 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) ||
428 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) {
429 ip6stat.ip6s_badscope++;
430 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
435 /* drop packets if interface ID portion is already filled */
436 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) {
437 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src) &&
438 ip6->ip6_src.s6_addr16[1]) {
439 ip6stat.ip6s_badscope++;
442 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst) &&
443 ip6->ip6_dst.s6_addr16[1]) {
444 ip6stat.ip6s_badscope++;
449 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src))
450 ip6->ip6_src.s6_addr16[1]
451 = htons(m->m_pkthdr.rcvif->if_index);
452 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst))
453 ip6->ip6_dst.s6_addr16[1]
454 = htons(m->m_pkthdr.rcvif->if_index);
456 #if 0 /* this case seems to be unnecessary. (jinmei, 20010401) */
458 * We use rt->rt_ifp to determine if the address is ours or not.
459 * If rt_ifp is lo0, the address is ours.
460 * The problem here is, rt->rt_ifp for fe80::%lo0/64 is set to lo0,
461 * so any address under fe80::%lo0/64 will be mistakenly considered
462 * local. The special case is supplied to handle the case properly
463 * by actually looking at interface addresses
464 * (using in6ifa_ifpwithaddr).
466 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) &&
467 IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) {
468 if (!in6ifa_ifpwithaddr(m->m_pkthdr.rcvif, &ip6->ip6_dst)) {
469 icmp6_error(m, ICMP6_DST_UNREACH,
470 ICMP6_DST_UNREACH_ADDR, 0);
471 /* m is already freed */
476 deliverifp = m->m_pkthdr.rcvif;
484 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
485 struct in6_multi *in6m = 0;
487 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast);
489 * See if we belong to the destination multicast group on the
492 IN6_LOOKUP_MULTI(ip6->ip6_dst, m->m_pkthdr.rcvif, in6m);
495 else if (!ip6_mrouter) {
496 ip6stat.ip6s_notmember++;
497 ip6stat.ip6s_cantforward++;
498 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
501 deliverifp = m->m_pkthdr.rcvif;
508 switch (ip6_ours_check_algorithm) {
511 * XXX: I intentionally broke our indentation rule here,
512 * since this switch-case is just for measurement and
513 * therefore should soon be removed.
515 if (ip6_forward_rt.ro_rt != NULL &&
516 (ip6_forward_rt.ro_rt->rt_flags & RTF_UP) &&
517 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
518 &((struct sockaddr_in6 *)(&ip6_forward_rt.ro_dst))->sin6_addr))
519 ip6stat.ip6s_forward_cachehit++;
521 struct sockaddr_in6 *dst6;
523 if (ip6_forward_rt.ro_rt) {
524 /* route is down or destination is different */
525 ip6stat.ip6s_forward_cachemiss++;
526 RTFREE(ip6_forward_rt.ro_rt);
527 ip6_forward_rt.ro_rt = 0;
530 bzero(&ip6_forward_rt.ro_dst, sizeof(struct sockaddr_in6));
531 dst6 = &ip6_forward_rt.ro_dst;
532 dst6->sin6_len = sizeof(struct sockaddr_in6);
533 dst6->sin6_family = AF_INET6;
534 dst6->sin6_addr = ip6->ip6_dst;
536 rtalloc_ign((struct route *)&ip6_forward_rt, RTF_PRCLONING);
539 #define rt6_key(r) ((struct sockaddr_in6 *)((r)->rt_nodes->rn_key))
542 * Accept the packet if the forwarding interface to the destination
543 * according to the routing table is the loopback interface,
544 * unless the associated route has a gateway.
545 * Note that this approach causes to accept a packet if there is a
546 * route to the loopback interface for the destination of the packet.
547 * But we think it's even useful in some situations, e.g. when using
548 * a special daemon which wants to intercept the packet.
550 * XXX: some OSes automatically make a cloned route for the destination
551 * of an outgoing packet. If the outgoing interface of the packet
552 * is a loopback one, the kernel would consider the packet to be
553 * accepted, even if we have no such address assinged on the interface.
554 * We check the cloned flag of the route entry to reject such cases,
555 * assuming that route entries for our own addresses are not made by
556 * cloning (it should be true because in6_addloop explicitly installs
557 * the host route). However, we might have to do an explicit check
558 * while it would be less efficient. Or, should we rather install a
559 * reject route for such a case?
561 if (ip6_forward_rt.ro_rt &&
562 (ip6_forward_rt.ro_rt->rt_flags &
563 (RTF_HOST|RTF_GATEWAY)) == RTF_HOST &&
565 !(ip6_forward_rt.ro_rt->rt_flags & RTF_WASCLONED) &&
568 !(ip6_forward_rt.ro_rt->rt_flags & RTF_CLONED) &&
572 * The check below is redundant since the comparison of
573 * the destination and the key of the rtentry has
574 * already done through looking up the routing table.
576 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
577 &rt6_key(ip6_forward_rt.ro_rt)->sin6_addr)
579 ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_LOOP) {
580 struct in6_ifaddr *ia6 =
581 (struct in6_ifaddr *)ip6_forward_rt.ro_rt->rt_ifa;
584 * record address information into m_aux.
586 ip6_setdstifaddr(m, ia6);
589 * packets to a tentative, duplicated, or somehow invalid
590 * address must not be accepted.
592 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) {
593 /* this address is ready */
595 deliverifp = ia6->ia_ifp; /* correct? */
596 /* Count the packet in the ip address stats */
597 ia6->ia_ifa.if_ipackets++;
598 ia6->ia_ifa.if_ibytes += m->m_pkthdr.len;
601 /* address is not ready, so discard the packet. */
603 "ip6_input: packet to an unready address %s->%s\n",
604 ip6_sprintf(&ip6->ip6_src),
605 ip6_sprintf(&ip6->ip6_dst)));
610 } /* XXX indentation (see above) */
613 * FAITH(Firewall Aided Internet Translator)
616 if (ip6_forward_rt.ro_rt && ip6_forward_rt.ro_rt->rt_ifp
617 && ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_FAITH) {
618 /* XXX do we need more sanity checks? */
620 deliverifp = ip6_forward_rt.ro_rt->rt_ifp; /* faith */
626 * Now there is no reason to process the packet if it's not our own
627 * and we're not a router.
629 if (!ip6_forwarding) {
630 ip6stat.ip6s_cantforward++;
631 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
637 * record address information into m_aux, if we don't have one yet.
638 * note that we are unable to record it, if the address is not listed
639 * as our interface address (e.g. multicast addresses, addresses
640 * within FAITH prefixes and such).
642 if (deliverifp && !ip6_getdstifaddr(m)) {
643 struct in6_ifaddr *ia6;
645 ia6 = in6_ifawithifp(deliverifp, &ip6->ip6_dst);
647 if (!ip6_setdstifaddr(m, ia6)) {
649 * XXX maybe we should drop the packet here,
650 * as we could not provide enough information
651 * to the upper layers.
658 * Process Hop-by-Hop options header if it's contained.
659 * m may be modified in ip6_hopopts_input().
660 * If a JumboPayload option is included, plen will also be modified.
662 plen = (u_int32_t)ntohs(ip6->ip6_plen);
663 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) {
666 if (ip6_hopopts_input(&plen, &rtalert, &m, &off)) {
667 #if 0 /*touches NULL pointer*/
668 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
670 goto bad2; /* m have already been freed */
674 ip6 = mtod(m, struct ip6_hdr *);
677 * if the payload length field is 0 and the next header field
678 * indicates Hop-by-Hop Options header, then a Jumbo Payload
679 * option MUST be included.
681 if (ip6->ip6_plen == 0 && plen == 0) {
683 * Note that if a valid jumbo payload option is
684 * contained, ip6_hoptops_input() must set a valid
685 * (non-zero) payload length to the variable plen.
687 ip6stat.ip6s_badoptions++;
688 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
689 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr);
690 icmp6_error(m, ICMP6_PARAM_PROB,
691 ICMP6_PARAMPROB_HEADER,
692 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6);
695 #ifndef PULLDOWN_TEST
696 /* ip6_hopopts_input() ensures that mbuf is contiguous */
697 hbh = (struct ip6_hbh *)(ip6 + 1);
699 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr),
700 sizeof(struct ip6_hbh));
702 ip6stat.ip6s_tooshort++;
709 * If we are acting as a router and the packet contains a
710 * router alert option, see if we know the option value.
711 * Currently, we only support the option value for MLD, in which
712 * case we should pass the packet to the multicast routing
715 if (rtalert != ~0 && ip6_forwarding) {
717 case IP6OPT_RTALERT_MLD:
722 * RFC2711 requires unrecognized values must be
732 * Check that the amount of data in the buffers
733 * is as at least much as the IPv6 header would have us expect.
734 * Trim mbufs if longer than we expect.
735 * Drop packet if shorter than we expect.
737 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) {
738 ip6stat.ip6s_tooshort++;
739 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);
742 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) {
743 if (m->m_len == m->m_pkthdr.len) {
744 m->m_len = sizeof(struct ip6_hdr) + plen;
745 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen;
747 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len);
751 * Forward if desirable.
753 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
755 * If we are acting as a multicast router, all
756 * incoming multicast packets are passed to the
757 * kernel-level multicast forwarding function.
758 * The packet is returned (relatively) intact; if
759 * ip6_mforward() returns a non-zero value, the packet
760 * must be discarded, else it may be accepted below.
762 if (ip6_mrouter && ip6_mforward(ip6, m->m_pkthdr.rcvif, m)) {
763 ip6stat.ip6s_cantforward++;
769 ip6_forward(m, srcrt);
773 ip6 = mtod(m, struct ip6_hdr *);
776 * Malicious party may be able to use IPv4 mapped addr to confuse
777 * tcp/udp stack and bypass security checks (act as if it was from
778 * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious.
780 * For SIIT end node behavior, you may want to disable the check.
781 * However, you will become vulnerable to attacks using IPv4 mapped
784 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
785 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
786 ip6stat.ip6s_badscope++;
787 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
792 * Tell launch routine the next header
794 ip6stat.ip6s_delivered++;
795 in6_ifstat_inc(deliverifp, ifs6_in_deliver);
799 while (nxt != IPPROTO_DONE) {
800 struct ip6protosw *sw6;
802 if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) {
803 ip6stat.ip6s_toomanyhdr++;
804 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr);
809 * protection against faulty packet - there should be
810 * more sanity checks in header chain processing.
812 if (m->m_pkthdr.len < off) {
813 ip6stat.ip6s_tooshort++;
814 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);
820 * do we need to do it for every header? yeah, other
821 * functions can play with it (like re-allocate and copy).
823 mhist = ip6_addaux(m);
824 if (mhist && M_TRAILINGSPACE(mhist) >= sizeof(nxt)) {
825 hist = mtod(mhist, caddr_t) + mhist->m_len;
826 bcopy(&nxt, hist, sizeof(nxt));
827 mhist->m_len += sizeof(nxt);
829 ip6stat.ip6s_toomanyhdr++;
834 if (nxt == IPPROTO_ROUTING) {
836 in6_ifstat_inc(m->m_pkthdr.rcvif,
838 ip6stat.ip6s_badoptions++;
843 sw6 = &inet6sw[ip6_protox[nxt]];
846 * enforce IPsec policy checking if we are seeing last header.
847 * note that we do not visit this with protocols with pcb layer
848 * code - like udp/tcp/raw ip.
850 if ((sw6->pr_flags & PR_LASTHDR) && ipsec6_in_reject(m, NULL)) {
851 ipsec6stat.in_polvio++;
856 * If this is a terminal header forward to the port, otherwise
857 * process synchronously for more headers.
859 if (sw6->pr_flags & PR_LASTHDR) {
860 struct netmsg_packet *pmsg;
863 port = sw6->pr_soport(NULL, NULL, &m);
864 KKASSERT(port != NULL);
865 pmsg = &m->m_hdr.mh_netmsg;
866 netmsg_init(&pmsg->nm_netmsg, NULL,
867 &netisr_apanic_rport,
868 0, transport6_processing_handler);
871 pmsg->nm_netmsg.nm_lmsg.u.ms_result = off;
872 lwkt_sendmsg(port, &pmsg->nm_netmsg.nm_lmsg);
876 nxt = sw6->pr_input(&m, &off, nxt);
884 /* msg was embedded in the mbuf, do not reply! */
888 * We have to call the pr_input() function from the correct protocol
889 * thread. The sw6->pr_soport() request at the end of ip6_input()
890 * returns the port and we forward a netmsg to the port to execute
894 transport6_processing_handler(netmsg_t netmsg)
896 struct netmsg_packet *pmsg = (struct netmsg_packet *)netmsg;
897 struct ip6protosw *sw6;
901 sw6 = &inet6sw[ip6_protox[pmsg->nm_nxt]];
902 hlen = pmsg->nm_netmsg.nm_lmsg.u.ms_result;
904 nxt = sw6->pr_input(&pmsg->nm_packet, &hlen, pmsg->nm_nxt);
905 KKASSERT(nxt == IPPROTO_DONE);
906 /* netmsg was embedded in the mbuf, do not reply! */
910 * set/grab in6_ifaddr correspond to IPv6 destination address.
911 * XXX backward compatibility wrapper
913 static struct ip6aux *
914 ip6_setdstifaddr(struct mbuf *m, struct in6_ifaddr *ia6)
920 n->ip6a_dstia6 = ia6;
921 return n; /* NULL if failed to set */
925 ip6_getdstifaddr(struct mbuf *m)
931 return n->ip6a_dstia6;
937 * Hop-by-Hop options header processing. If a valid jumbo payload option is
938 * included, the real payload length will be stored in plenp.
941 ip6_hopopts_input(u_int32_t *plenp,
942 u_int32_t *rtalertp,/* XXX: should be stored more smart way */
946 struct mbuf *m = *mp;
947 int off = *offp, hbhlen;
951 /* validation of the length of the header */
952 #ifndef PULLDOWN_TEST
953 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1);
954 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off);
955 hbhlen = (hbh->ip6h_len + 1) << 3;
957 IP6_EXTHDR_CHECK(m, off, hbhlen, -1);
958 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off);
960 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m,
961 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh));
963 ip6stat.ip6s_tooshort++;
966 hbhlen = (hbh->ip6h_len + 1) << 3;
967 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr),
970 ip6stat.ip6s_tooshort++;
975 hbhlen -= sizeof(struct ip6_hbh);
976 opt = (u_int8_t *)hbh + sizeof(struct ip6_hbh);
978 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh),
979 hbhlen, rtalertp, plenp) < 0)
988 * Search header for all Hop-by-hop options and process each option.
989 * This function is separate from ip6_hopopts_input() in order to
990 * handle a case where the sending node itself process its hop-by-hop
991 * options header. In such a case, the function is called from ip6_output().
993 * The function assumes that hbh header is located right after the IPv6 header
994 * (RFC2460 p7), opthead is pointer into data content in m, and opthead to
995 * opthead + hbhlen is located in continuous memory region.
998 ip6_process_hopopts(struct mbuf *m, u_int8_t *opthead, int hbhlen,
999 u_int32_t *rtalertp, u_int32_t *plenp)
1001 struct ip6_hdr *ip6;
1003 u_int8_t *opt = opthead;
1004 u_int16_t rtalert_val;
1005 u_int32_t jumboplen;
1006 const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh);
1008 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) {
1014 if (hbhlen < IP6OPT_MINLEN) {
1015 ip6stat.ip6s_toosmall++;
1018 optlen = *(opt + 1) + 2;
1020 case IP6OPT_RTALERT:
1021 /* XXX may need check for alignment */
1022 if (hbhlen < IP6OPT_RTALERT_LEN) {
1023 ip6stat.ip6s_toosmall++;
1026 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) {
1028 icmp6_error(m, ICMP6_PARAM_PROB,
1029 ICMP6_PARAMPROB_HEADER,
1030 erroff + opt + 1 - opthead);
1033 optlen = IP6OPT_RTALERT_LEN;
1034 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2);
1035 *rtalertp = ntohs(rtalert_val);
1038 /* XXX may need check for alignment */
1039 if (hbhlen < IP6OPT_JUMBO_LEN) {
1040 ip6stat.ip6s_toosmall++;
1043 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) {
1045 icmp6_error(m, ICMP6_PARAM_PROB,
1046 ICMP6_PARAMPROB_HEADER,
1047 erroff + opt + 1 - opthead);
1050 optlen = IP6OPT_JUMBO_LEN;
1053 * IPv6 packets that have non 0 payload length
1054 * must not contain a jumbo payload option.
1056 ip6 = mtod(m, struct ip6_hdr *);
1057 if (ip6->ip6_plen) {
1058 ip6stat.ip6s_badoptions++;
1059 icmp6_error(m, ICMP6_PARAM_PROB,
1060 ICMP6_PARAMPROB_HEADER,
1061 erroff + opt - opthead);
1066 * We may see jumbolen in unaligned location, so
1067 * we'd need to perform bcopy().
1069 bcopy(opt + 2, &jumboplen, sizeof(jumboplen));
1070 jumboplen = (u_int32_t)htonl(jumboplen);
1074 * if there are multiple jumbo payload options,
1075 * *plenp will be non-zero and the packet will be
1077 * the behavior may need some debate in ipngwg -
1078 * multiple options does not make sense, however,
1079 * there's no explicit mention in specification.
1082 ip6stat.ip6s_badoptions++;
1083 icmp6_error(m, ICMP6_PARAM_PROB,
1084 ICMP6_PARAMPROB_HEADER,
1085 erroff + opt + 2 - opthead);
1091 * jumbo payload length must be larger than 65535.
1093 if (jumboplen <= IPV6_MAXPACKET) {
1094 ip6stat.ip6s_badoptions++;
1095 icmp6_error(m, ICMP6_PARAM_PROB,
1096 ICMP6_PARAMPROB_HEADER,
1097 erroff + opt + 2 - opthead);
1103 default: /* unknown option */
1104 if (hbhlen < IP6OPT_MINLEN) {
1105 ip6stat.ip6s_toosmall++;
1108 optlen = ip6_unknown_opt(opt, m,
1109 erroff + opt - opthead);
1125 * Unknown option processing.
1126 * The third argument `off' is the offset from the IPv6 header to the option,
1127 * which is necessary if the IPv6 header the and option header and IPv6 header
1128 * is not continuous in order to return an ICMPv6 error.
1131 ip6_unknown_opt(u_int8_t *optp, struct mbuf *m, int off)
1133 struct ip6_hdr *ip6;
1135 switch (IP6OPT_TYPE(*optp)) {
1136 case IP6OPT_TYPE_SKIP: /* ignore the option */
1137 return ((int)*(optp + 1));
1138 case IP6OPT_TYPE_DISCARD: /* silently discard */
1141 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */
1142 ip6stat.ip6s_badoptions++;
1143 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off);
1145 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */
1146 ip6stat.ip6s_badoptions++;
1147 ip6 = mtod(m, struct ip6_hdr *);
1148 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) ||
1149 (m->m_flags & (M_BCAST|M_MCAST)))
1152 icmp6_error(m, ICMP6_PARAM_PROB,
1153 ICMP6_PARAMPROB_OPTION, off);
1157 m_freem(m); /* XXX: NOTREACHED */
1162 * Create the "control" list for this pcb.
1163 * The function will not modify mbuf chain at all.
1165 * with KAME mbuf chain restriction:
1166 * The routine will be called from upper layer handlers like tcp6_input().
1167 * Thus the routine assumes that the caller (tcp6_input) have already
1168 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the
1169 * very first mbuf on the mbuf chain.
1172 ip6_savecontrol(struct inpcb *in6p, struct mbuf **mp, struct ip6_hdr *ip6,
1175 #define IS2292(x, y) ((in6p->in6p_flags & IN6P_RFC2292) ? (x) : (y))
1176 struct thread *td = curthread; /* XXX */
1178 int rthdr_exist = 0;
1181 if (priv_check(td, PRIV_ROOT) == 0)
1185 if (in6p->in6p_socket->so_options & SO_TIMESTAMP) {
1189 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv),
1190 SCM_TIMESTAMP, SOL_SOCKET);
1192 mp = &(*mp)->m_next;
1197 /* RFC 2292 sec. 5 */
1198 if (in6p->in6p_flags & IN6P_PKTINFO) {
1199 struct in6_pktinfo pi6;
1200 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr));
1201 if (IN6_IS_SCOPE_LINKLOCAL(&pi6.ipi6_addr))
1202 pi6.ipi6_addr.s6_addr16[1] = 0;
1203 pi6.ipi6_ifindex = (m && m->m_pkthdr.rcvif)
1204 ? m->m_pkthdr.rcvif->if_index
1206 *mp = sbcreatecontrol((caddr_t) &pi6,
1207 sizeof(struct in6_pktinfo), IS2292(IPV6_2292PKTINFO, IPV6_PKTINFO),
1210 mp = &(*mp)->m_next;
1213 if (in6p->in6p_flags & IN6P_HOPLIMIT) {
1214 int hlim = ip6->ip6_hlim & 0xff;
1215 *mp = sbcreatecontrol((caddr_t) &hlim,
1216 sizeof(int), IS2292(IPV6_2292HOPLIMIT, IPV6_HOPLIMIT), IPPROTO_IPV6);
1218 mp = &(*mp)->m_next;
1221 if ((in6p->in6p_flags & IN6P_TCLASS) != 0) {
1225 flowinfo = (u_int32_t)ntohl(ip6->ip6_flow & IPV6_FLOWINFO_MASK);
1228 tclass = flowinfo & 0xff;
1229 *mp = sbcreatecontrol((caddr_t) &tclass, sizeof(tclass),
1230 IPV6_TCLASS, IPPROTO_IPV6);
1232 mp = &(*mp)->m_next;
1236 * IPV6_HOPOPTS socket option. We require super-user privilege
1237 * for the option, but it might be too strict, since there might
1238 * be some hop-by-hop options which can be returned to normal user.
1239 * See RFC 2292 section 6.
1241 if ((in6p->in6p_flags & IN6P_HOPOPTS) && privileged) {
1243 * Check if a hop-by-hop options header is contatined in the
1244 * received packet, and if so, store the options as ancillary
1245 * data. Note that a hop-by-hop options header must be
1246 * just after the IPv6 header, which fact is assured through
1247 * the IPv6 input processing.
1249 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1250 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) {
1251 struct ip6_hbh *hbh;
1253 #ifdef PULLDOWN_TEST
1257 #ifndef PULLDOWN_TEST
1258 hbh = (struct ip6_hbh *)(ip6 + 1);
1259 hbhlen = (hbh->ip6h_len + 1) << 3;
1261 ext = ip6_pullexthdr(m, sizeof(struct ip6_hdr),
1264 ip6stat.ip6s_tooshort++;
1267 hbh = mtod(ext, struct ip6_hbh *);
1268 hbhlen = (hbh->ip6h_len + 1) << 3;
1269 if (hbhlen != ext->m_len) {
1271 ip6stat.ip6s_tooshort++;
1277 * XXX: We copy whole the header even if a jumbo
1278 * payload option is included, which option is to
1279 * be removed before returning in the RFC 2292.
1280 * Note: this constraint is removed in 2292bis.
1282 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen,
1283 IS2292(IPV6_2292HOPOPTS, IPV6_HOPOPTS), IPPROTO_IPV6);
1285 mp = &(*mp)->m_next;
1286 #ifdef PULLDOWN_TEST
1292 /* IPV6_DSTOPTS and IPV6_RTHDR socket options */
1293 if ((in6p->in6p_flags & (IN6P_DSTOPTS | IN6P_RTHDRDSTOPTS)) != 0) {
1294 int proto, off, nxt;
1297 * go through the header chain to see if a routing header is
1298 * contained in the packet. We need this information to store
1299 * destination options headers (if any) properly.
1300 * XXX: performance issue. We should record this info when
1301 * processing extension headers in incoming routine.
1304 proto = IPPROTO_IPV6;
1310 newoff = ip6_nexthdr(m, off, proto, &nxt);
1313 if (newoff < off) /* invalid, check for safety */
1315 if ((proto = nxt) == IPPROTO_ROUTING) {
1323 if ((in6p->in6p_flags &
1324 (IN6P_RTHDR | IN6P_DSTOPTS | IN6P_RTHDRDSTOPTS)) != 0) {
1325 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1326 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr);
1329 * Search for destination options headers or routing
1330 * header(s) through the header chain, and stores each
1331 * header as ancillary data.
1332 * Note that the order of the headers remains in
1333 * the chain of ancillary data.
1335 while (1) { /* is explicit loop prevention necessary? */
1336 struct ip6_ext *ip6e = NULL;
1338 #ifdef PULLDOWN_TEST
1339 struct mbuf *ext = NULL;
1343 * if it is not an extension header, don't try to
1344 * pull it from the chain.
1347 case IPPROTO_DSTOPTS:
1348 case IPPROTO_ROUTING:
1349 case IPPROTO_HOPOPTS:
1350 case IPPROTO_AH: /* is it possible? */
1356 #ifndef PULLDOWN_TEST
1357 if (off + sizeof(*ip6e) > m->m_len)
1359 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off);
1360 if (nxt == IPPROTO_AH)
1361 elen = (ip6e->ip6e_len + 2) << 2;
1363 elen = (ip6e->ip6e_len + 1) << 3;
1364 if (off + elen > m->m_len)
1367 ext = ip6_pullexthdr(m, off, nxt);
1369 ip6stat.ip6s_tooshort++;
1372 ip6e = mtod(ext, struct ip6_ext *);
1373 if (nxt == IPPROTO_AH)
1374 elen = (ip6e->ip6e_len + 2) << 2;
1376 elen = (ip6e->ip6e_len + 1) << 3;
1377 if (elen != ext->m_len) {
1379 ip6stat.ip6s_tooshort++;
1385 case IPPROTO_DSTOPTS:
1386 if ((in6p->in6p_flags & IN6P_DSTOPTS) == 0)
1390 * We also require super-user privilege for
1392 * See the comments on IN6_HOPOPTS.
1397 *mp = sbcreatecontrol((caddr_t)ip6e, elen,
1398 IS2292(IPV6_2292DSTOPTS, IPV6_DSTOPTS),
1401 mp = &(*mp)->m_next;
1403 case IPPROTO_ROUTING:
1404 if (!in6p->in6p_flags & IN6P_RTHDR)
1407 *mp = sbcreatecontrol((caddr_t)ip6e, elen,
1408 IS2292(IPV6_2292RTHDR, IPV6_RTHDR),
1411 mp = &(*mp)->m_next;
1413 case IPPROTO_HOPOPTS:
1414 case IPPROTO_AH: /* is it possible? */
1419 * other cases have been filtered in the above.
1420 * none will visit this case. here we supply
1421 * the code just in case (nxt overwritten or
1424 #ifdef PULLDOWN_TEST
1431 /* proceed with the next header. */
1433 nxt = ip6e->ip6e_nxt;
1435 #ifdef PULLDOWN_TEST
1447 ip6_notify_pmtu(struct inpcb *in6p, struct sockaddr_in6 *dst, u_int32_t *mtu)
1451 struct ip6_mtuinfo mtuctl;
1453 so = in6p->inp_socket;
1459 if (so == NULL) /* I believe this is impossible */
1460 panic("ip6_notify_pmtu: socket is NULL");
1463 bzero(&mtuctl, sizeof(mtuctl)); /* zero-clear for safety */
1464 mtuctl.ip6m_mtu = *mtu;
1465 mtuctl.ip6m_addr = *dst;
1467 if ((m_mtu = sbcreatecontrol((caddr_t)&mtuctl, sizeof(mtuctl),
1468 IPV6_PATHMTU, IPPROTO_IPV6)) == NULL)
1471 if (sbappendaddr(&so->so_rcv.sb, (struct sockaddr *)dst, NULL, m_mtu)
1474 /* XXX: should count statistics */
1481 #ifdef PULLDOWN_TEST
1483 * pull single extension header from mbuf chain. returns single mbuf that
1484 * contains the result, or NULL on error.
1486 static struct mbuf *
1487 ip6_pullexthdr(struct mbuf *m, size_t off, int nxt)
1489 struct ip6_ext ip6e;
1495 case IPPROTO_DSTOPTS:
1496 case IPPROTO_ROUTING:
1497 case IPPROTO_HOPOPTS:
1498 case IPPROTO_AH: /* is it possible? */
1501 kprintf("ip6_pullexthdr: invalid nxt=%d\n", nxt);
1505 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
1506 if (nxt == IPPROTO_AH)
1507 elen = (ip6e.ip6e_len + 2) << 2;
1509 elen = (ip6e.ip6e_len + 1) << 3;
1511 n = m_getb(elen, MB_DONTWAIT, MT_DATA, 0);
1516 if (elen >= M_TRAILINGSPACE(n)) {
1521 m_copydata(m, off, elen, mtod(n, caddr_t));
1528 * Get pointer to the previous header followed by the header
1529 * currently processed.
1530 * XXX: This function supposes that
1531 * M includes all headers,
1532 * the next header field and the header length field of each header
1534 * the sum of each header length equals to OFF.
1535 * Because of these assumptions, this function must be called very
1536 * carefully. Moreover, it will not be used in the near future when
1537 * we develop `neater' mechanism to process extension headers.
1540 ip6_get_prevhdr(struct mbuf *m, int off)
1542 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1544 if (off == sizeof(struct ip6_hdr))
1545 return (&ip6->ip6_nxt);
1548 struct ip6_ext *ip6e = NULL;
1551 len = sizeof(struct ip6_hdr);
1553 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len);
1556 case IPPROTO_FRAGMENT:
1557 len += sizeof(struct ip6_frag);
1560 len += (ip6e->ip6e_len + 2) << 2;
1563 len += (ip6e->ip6e_len + 1) << 3;
1566 nxt = ip6e->ip6e_nxt;
1569 return (&ip6e->ip6e_nxt);
1576 * get next header offset. m will be retained.
1579 ip6_nexthdr(struct mbuf *m, int off, int proto, int *nxtp)
1582 struct ip6_ext ip6e;
1587 panic("ip6_nexthdr: m == NULL");
1588 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off)
1593 if (m->m_pkthdr.len < off + sizeof(ip6))
1595 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6);
1597 *nxtp = ip6.ip6_nxt;
1601 case IPPROTO_FRAGMENT:
1603 * terminate parsing if it is not the first fragment,
1604 * it does not make sense to parse through it.
1606 if (m->m_pkthdr.len < off + sizeof(fh))
1608 m_copydata(m, off, sizeof(fh), (caddr_t)&fh);
1609 /* IP6F_OFF_MASK = 0xfff8(BigEndian), 0xf8ff(LittleEndian) */
1610 if (fh.ip6f_offlg & IP6F_OFF_MASK)
1613 *nxtp = fh.ip6f_nxt;
1614 off += sizeof(struct ip6_frag);
1618 if (m->m_pkthdr.len < off + sizeof(ip6e))
1620 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
1622 *nxtp = ip6e.ip6e_nxt;
1623 off += (ip6e.ip6e_len + 2) << 2;
1626 case IPPROTO_HOPOPTS:
1627 case IPPROTO_ROUTING:
1628 case IPPROTO_DSTOPTS:
1629 if (m->m_pkthdr.len < off + sizeof(ip6e))
1631 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
1633 *nxtp = ip6e.ip6e_nxt;
1634 off += (ip6e.ip6e_len + 1) << 3;
1639 case IPPROTO_IPCOMP:
1651 * get offset for the last header in the chain. m will be kept untainted.
1654 ip6_lasthdr(struct mbuf *m, int off, int proto, int *nxtp)
1664 newoff = ip6_nexthdr(m, off, proto, nxtp);
1667 else if (newoff < off)
1668 return -1; /* invalid */
1669 else if (newoff == off)
1678 ip6_addaux(struct mbuf *m)
1680 struct m_tag *tag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL);
1682 tag = m_tag_get(PACKET_TAG_IPV6_INPUT,
1683 sizeof (struct ip6aux),
1686 m_tag_prepend(m, tag);
1689 bzero(m_tag_data(tag), sizeof (struct ip6aux));
1690 return tag ? (struct ip6aux *)m_tag_data(tag) : NULL;
1694 ip6_findaux(struct mbuf *m)
1696 struct m_tag *tag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL);
1697 return tag ? (struct ip6aux*)(tag+1) : NULL;
1701 ip6_delaux(struct mbuf *m)
1703 struct m_tag *tag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL);
1705 m_tag_delete(m, tag);
1709 * System control for IP6
1712 u_char inet6ctlerrmap[PRC_NCMDS] = {
1714 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH,
1715 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED,
1716 EMSGSIZE, EHOSTUNREACH, 0, 0,