2 /* $OpenBSD: ipsec_input.c,v 1.63 2003/02/20 18:35:43 deraadt Exp $ */
4 * The authors of this code are John Ioannidis (ji@tla.org),
5 * Angelos D. Keromytis (kermit@csd.uch.gr) and
6 * Niels Provos (provos@physnet.uni-hamburg.de).
8 * This code was written by John Ioannidis for BSD/OS in Athens, Greece,
11 * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
12 * by Angelos D. Keromytis.
14 * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis
17 * Additional features in 1999 by Angelos D. Keromytis.
19 * Copyright (C) 1995, 1996, 1997, 1998, 1999 by John Ioannidis,
20 * Angelos D. Keromytis and Niels Provos.
21 * Copyright (c) 2001, Angelos D. Keromytis.
23 * Permission to use, copy, and modify this software with or without fee
24 * is hereby granted, provided that this entire notice is included in
25 * all copies of any software which is or includes a copy or
26 * modification of this software.
27 * You may use this code under the GNU public license if you so wish. Please
28 * contribute changes back to the authors under this freer than GPL license
29 * so that we may further the use of strong encryption without limitations to
32 * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
33 * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
34 * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
35 * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
40 * IPsec input processing.
44 #include "opt_inet6.h"
45 #include "opt_ipsec.h"
48 #include <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/malloc.h>
52 #include <sys/domain.h>
53 #include <sys/protosw.h>
54 #include <sys/socket.h>
55 #include <sys/errno.h>
56 #include <sys/syslog.h>
60 #include <net/route.h>
61 #include <net/netisr.h>
64 #include <netinet/in.h>
65 #include <netinet/in_systm.h>
66 #include <netinet/ip.h>
67 #include <netinet/ip_var.h>
68 #include <netinet/in_var.h>
70 #include <netinet/ip6.h>
72 #include <netinet6/ip6_var.h>
74 #include <netinet/in_pcb.h>
76 #include <netinet/icmp6.h>
79 #include <netipsec/ipsec.h>
81 #include <netipsec/ipsec6.h>
83 #include <netipsec/ah_var.h>
84 #include <netipsec/esp.h>
85 #include <netipsec/esp_var.h>
86 #include <netipsec/ipcomp_var.h>
88 #include <netipsec/key.h>
89 #include <netipsec/keydb.h>
91 #include <netipsec/xform.h>
92 #include <netinet6/ip6protosw.h>
94 #include <machine/in_cksum.h>
95 #include <machine/stdarg.h>
98 #include <net/if_enc.h>
102 #define IPSEC_ISTAT(proto, name) do { \
103 if ((proto) == IPPROTO_ESP) \
104 ESPSTAT_INC(esps_##name); \
105 else if ((proto) == IPPROTO_AH) \
106 AHSTAT_INC(ahs_##name); \
108 IPCOMPSTAT_INC(ipcomps_##name); \
112 static void ipsec4_common_ctlinput(int, struct sockaddr *, void *, int);
116 * ipsec_common_input gets called when an IPsec-protected packet
117 * is received by IPv4 or IPv6. Its job is to find the right SA
118 * and call the appropriate transform. The transform callback
119 * takes care of further processing (like ingress filtering).
122 ipsec_common_input(struct mbuf *m, int skip, int protoff, int af, int sproto)
124 union sockaddr_union dst_address;
125 struct secasvar *sav;
134 IPSEC_ISTAT(sproto, input);
136 IPSEC_ASSERT(m != NULL, ("null packet"));
138 IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH ||
139 sproto == IPPROTO_IPCOMP,
140 ("unexpected security protocol %u", sproto));
142 if ((sproto == IPPROTO_ESP && !V_esp_enable) ||
143 (sproto == IPPROTO_AH && !V_ah_enable) ||
144 (sproto == IPPROTO_IPCOMP && !V_ipcomp_enable)) {
146 IPSEC_ISTAT(sproto, pdrops);
150 if (m->m_pkthdr.len - skip < 2 * sizeof (u_int32_t)) {
152 IPSEC_ISTAT(sproto, hdrops);
153 DPRINTF(("%s: packet too small\n", __func__));
157 /* Retrieve the SPI from the relevant IPsec header */
158 if (sproto == IPPROTO_ESP)
159 m_copydata(m, skip, sizeof(u_int32_t), (caddr_t) &spi);
160 else if (sproto == IPPROTO_AH)
161 m_copydata(m, skip + sizeof(u_int32_t), sizeof(u_int32_t),
163 else if (sproto == IPPROTO_IPCOMP) {
165 m_copydata(m, skip + sizeof(u_int16_t), sizeof(u_int16_t),
167 spi = ntohl(htons(cpi));
171 * Find the SA and (indirectly) call the appropriate
172 * kernel crypto routine. The resulting mbuf chain is a valid
173 * IP packet ready to go through input processing.
175 bzero(&dst_address, sizeof (dst_address));
176 dst_address.sa.sa_family = af;
180 dst_address.sin.sin_len = sizeof(struct sockaddr_in);
181 m_copydata(m, offsetof(struct ip, ip_dst),
182 sizeof(struct in_addr),
183 (caddr_t) &dst_address.sin.sin_addr);
185 /* Find the source port for NAT-T; see udp*_espdecap. */
186 tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL);
188 dst_address.sin.sin_port = ((u_int16_t *)(tag + 1))[1];
189 #endif /* IPSEC_NAT_T */
194 dst_address.sin6.sin6_len = sizeof(struct sockaddr_in6);
195 m_copydata(m, offsetof(struct ip6_hdr, ip6_dst),
196 sizeof(struct in6_addr),
197 (caddr_t) &dst_address.sin6.sin6_addr);
201 DPRINTF(("%s: unsupported protocol family %u\n", __func__, af));
203 IPSEC_ISTAT(sproto, nopf);
207 /* NB: only pass dst since key_allocsa follows RFC2401 */
208 sav = KEY_ALLOCSA(&dst_address, sproto, spi);
210 DPRINTF(("%s: no key association found for SA %s/%08lx/%u\n",
211 __func__, ipsec_address(&dst_address),
212 (u_long) ntohl(spi), sproto));
213 IPSEC_ISTAT(sproto, notdb);
218 if (sav->tdb_xform == NULL) {
219 DPRINTF(("%s: attempted to use uninitialized SA %s/%08lx/%u\n",
220 __func__, ipsec_address(&dst_address),
221 (u_long) ntohl(spi), sproto));
222 IPSEC_ISTAT(sproto, noxform);
229 * Call appropriate transform and return -- callback takes care of
232 error = (*sav->tdb_xform->xf_input)(m, sav, skip, protoff);
239 * Common input handler for IPv4 AH, ESP, and IPCOMP.
242 ipsec4_common_input(struct mbuf *m, ...)
248 off = va_arg(ap, int);
249 nxt = va_arg(ap, int);
252 return ipsec_common_input(m, off, offsetof(struct ip, ip_p),
257 ah4_input(struct mbuf *m, int off)
259 ipsec4_common_input(m, off, IPPROTO_AH);
262 ah4_ctlinput(int cmd, struct sockaddr *sa, void *v)
264 if (sa->sa_family == AF_INET &&
265 sa->sa_len == sizeof(struct sockaddr_in))
266 ipsec4_common_ctlinput(cmd, sa, v, IPPROTO_AH);
270 esp4_input(struct mbuf *m, int off)
272 ipsec4_common_input(m, off, IPPROTO_ESP);
275 esp4_ctlinput(int cmd, struct sockaddr *sa, void *v)
277 if (sa->sa_family == AF_INET &&
278 sa->sa_len == sizeof(struct sockaddr_in))
279 ipsec4_common_ctlinput(cmd, sa, v, IPPROTO_ESP);
283 ipcomp4_input(struct mbuf *m, int off)
285 ipsec4_common_input(m, off, IPPROTO_IPCOMP);
289 * IPsec input callback for INET protocols.
290 * This routine is called as the transform callback.
291 * Takes care of filtering and other sanity checks on
292 * the processed packet.
295 ipsec4_common_input_cb(struct mbuf *m, struct secasvar *sav,
296 int skip, int protoff, struct m_tag *mt)
298 int prot, af, sproto;
301 struct tdb_ident *tdbi;
302 struct secasindex *saidx;
306 char ip6buf[INET6_ADDRSTRLEN];
310 IPSEC_ASSERT(m != NULL, ("null mbuf"));
311 IPSEC_ASSERT(sav != NULL, ("null SA"));
312 IPSEC_ASSERT(sav->sah != NULL, ("null SAH"));
313 saidx = &sav->sah->saidx;
314 af = saidx->dst.sa.sa_family;
315 IPSEC_ASSERT(af == AF_INET, ("unexpected af %u", af));
316 sproto = saidx->proto;
317 IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH ||
318 sproto == IPPROTO_IPCOMP,
319 ("unexpected security protocol %u", sproto));
323 DPRINTF(("%s: null mbuf", __func__));
324 IPSEC_ISTAT(sproto, badkcr);
330 /* Fix IPv4 header */
331 if (m->m_len < skip && (m = m_pullup(m, skip)) == NULL) {
332 DPRINTF(("%s: processing failed for SA %s/%08lx\n",
333 __func__, ipsec_address(&sav->sah->saidx.dst),
334 (u_long) ntohl(sav->spi)));
335 IPSEC_ISTAT(sproto, hdrops);
340 ip = mtod(m, struct ip *);
341 ip->ip_len = htons(m->m_pkthdr.len);
342 ip->ip_off = htons(ip->ip_off);
344 ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
346 ip = mtod(m, struct ip *);
351 /* IP-in-IP encapsulation */
352 if (prot == IPPROTO_IPIP) {
355 if (m->m_pkthdr.len - skip < sizeof(struct ip)) {
356 IPSEC_ISTAT(sproto, hdrops);
360 /* ipn will now contain the inner IPv4 header */
361 m_copydata(m, ip->ip_hl << 2, sizeof(struct ip),
364 /* XXX PROXY address isn't recorded in SAH */
366 * Check that the inner source address is the same as
367 * the proxy address, if available.
369 if ((saidx->proxy.sa.sa_family == AF_INET &&
370 saidx->proxy.sin.sin_addr.s_addr !=
373 saidx->proxy.sin.sin_addr.s_addr) ||
374 (saidx->proxy.sa.sa_family != AF_INET &&
375 saidx->proxy.sa.sa_family != 0)) {
377 DPRINTF(("%s: inner source address %s doesn't "
378 "correspond to expected proxy source %s, "
379 "SA %s/%08lx\n", __func__,
380 inet_ntoa4(ipn.ip_src),
381 ipsp_address(saidx->proxy),
382 ipsp_address(saidx->dst),
383 (u_long) ntohl(sav->spi)));
385 IPSEC_ISTAT(sproto, pdrops);
391 /* IPv6-in-IP encapsulation. */
392 if (prot == IPPROTO_IPV6) {
395 if (m->m_pkthdr.len - skip < sizeof(struct ip6_hdr)) {
396 IPSEC_ISTAT(sproto, hdrops);
400 /* ip6n will now contain the inner IPv6 header. */
401 m_copydata(m, ip->ip_hl << 2, sizeof(struct ip6_hdr),
405 * Check that the inner source address is the same as
406 * the proxy address, if available.
408 if ((saidx->proxy.sa.sa_family == AF_INET6 &&
409 !IN6_IS_ADDR_UNSPECIFIED(&saidx->proxy.sin6.sin6_addr) &&
410 !IN6_ARE_ADDR_EQUAL(&ip6n.ip6_src,
411 &saidx->proxy.sin6.sin6_addr)) ||
412 (saidx->proxy.sa.sa_family != AF_INET6 &&
413 saidx->proxy.sa.sa_family != 0)) {
415 DPRINTF(("%s: inner source address %s doesn't "
416 "correspond to expected proxy source %s, "
417 "SA %s/%08lx\n", __func__,
418 ip6_sprintf(ip6buf, &ip6n.ip6_src),
419 ipsec_address(&saidx->proxy),
420 ipsec_address(&saidx->dst),
421 (u_long) ntohl(sav->spi)));
423 IPSEC_ISTAT(sproto, pdrops);
432 * Record what we've done to the packet (under what SA it was
433 * processed). If we've been passed an mtag, it means the packet
434 * was already processed by an ethernet/crypto combo card and
435 * thus has a tag attached with all the right information, but
436 * with a PACKET_TAG_IPSEC_IN_CRYPTO_DONE as opposed to
437 * PACKET_TAG_IPSEC_IN_DONE type; in that case, just change the type.
439 if (mt == NULL && sproto != IPPROTO_IPCOMP) {
440 mtag = m_tag_get(PACKET_TAG_IPSEC_IN_DONE,
441 sizeof(struct tdb_ident), M_NOWAIT);
443 DPRINTF(("%s: failed to get tag\n", __func__));
444 IPSEC_ISTAT(sproto, hdrops);
449 tdbi = (struct tdb_ident *)(mtag + 1);
450 bcopy(&saidx->dst, &tdbi->dst, saidx->dst.sa.sa_len);
451 tdbi->proto = sproto;
452 tdbi->spi = sav->spi;
453 /* Cache those two for enc(4) in xform_ipip. */
454 tdbi->alg_auth = sav->alg_auth;
455 tdbi->alg_enc = sav->alg_enc;
457 m_tag_prepend(m, mtag);
458 } else if (mt != NULL) {
459 mt->m_tag_id = PACKET_TAG_IPSEC_IN_DONE;
460 /* XXX do we need to mark m_flags??? */
463 key_sa_recordxfer(sav, m); /* record data transfer */
468 encif->if_ipackets++;
469 encif->if_ibytes += m->m_pkthdr.len;
472 * Pass the mbuf to enc0 for bpf and pfil. We will filter the IPIP
473 * packet later after it has been decapsulated.
475 ipsec_bpf(m, sav, AF_INET, ENC_IN|ENC_BEFORE);
477 if (prot != IPPROTO_IPIP)
478 if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_BEFORE)) != 0)
483 * Re-dispatch via software interrupt.
485 if ((error = netisr_queue_src(NETISR_IP, (uintptr_t)sav->spi, m))) {
486 IPSEC_ISTAT(sproto, qfull);
487 DPRINTF(("%s: queue full; proto %u packet dropped\n",
498 ipsec4_common_ctlinput(int cmd, struct sockaddr *sa, void *v, int proto)
500 /* XXX nothing just yet */
505 /* IPv6 AH wrapper. */
507 ipsec6_common_input(struct mbuf **mp, int *offp, int proto)
513 if (*offp < sizeof(struct ip6_hdr)) {
514 DPRINTF(("%s: bad offset %u\n", __func__, *offp));
516 } else if (*offp == sizeof(struct ip6_hdr)) {
517 protoff = offsetof(struct ip6_hdr, ip6_nxt);
519 /* Chase down the header chain... */
520 protoff = sizeof(struct ip6_hdr);
524 m_copydata(*mp, protoff, sizeof(ip6e),
527 if (ip6e.ip6e_nxt == IPPROTO_AH)
528 l = (ip6e.ip6e_len + 2) << 2;
530 l = (ip6e.ip6e_len + 1) << 3;
531 IPSEC_ASSERT(l > 0, ("l went zero or negative"));
532 } while (protoff + l < *offp);
534 /* Malformed packet check */
535 if (protoff + l != *offp) {
536 DPRINTF(("%s: bad packet header chain, protoff %u, "
537 "l %u, off %u\n", __func__, protoff, l, *offp));
538 IPSEC_ISTAT(proto, hdrops);
543 protoff += offsetof(struct ip6_ext, ip6e_nxt);
545 (void) ipsec_common_input(*mp, *offp, protoff, AF_INET6, proto);
550 * IPsec input callback, called by the transform callback. Takes care of
551 * filtering and other sanity checks on the processed packet.
554 ipsec6_common_input_cb(struct mbuf *m, struct secasvar *sav, int skip, int protoff,
557 int prot, af, sproto;
560 struct tdb_ident *tdbi;
561 struct secasindex *saidx;
566 char ip6buf[INET6_ADDRSTRLEN];
569 IPSEC_ASSERT(m != NULL, ("null mbuf"));
570 IPSEC_ASSERT(sav != NULL, ("null SA"));
571 IPSEC_ASSERT(sav->sah != NULL, ("null SAH"));
572 saidx = &sav->sah->saidx;
573 af = saidx->dst.sa.sa_family;
574 IPSEC_ASSERT(af == AF_INET6, ("unexpected af %u", af));
575 sproto = saidx->proto;
576 IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH ||
577 sproto == IPPROTO_IPCOMP,
578 ("unexpected security protocol %u", sproto));
582 DPRINTF(("%s: null mbuf", __func__));
583 IPSEC_ISTAT(sproto, badkcr);
588 /* Fix IPv6 header */
589 if (m->m_len < sizeof(struct ip6_hdr) &&
590 (m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) {
592 DPRINTF(("%s: processing failed for SA %s/%08lx\n",
593 __func__, ipsec_address(&sav->sah->saidx.dst),
594 (u_long) ntohl(sav->spi)));
596 IPSEC_ISTAT(sproto, hdrops);
601 ip6 = mtod(m, struct ip6_hdr *);
602 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
606 m_copydata(m, protoff, 1, (unsigned char *) &prot);
610 /* IP-in-IP encapsulation */
611 if (prot == IPPROTO_IPIP) {
614 if (m->m_pkthdr.len - skip < sizeof(struct ip)) {
615 IPSEC_ISTAT(sproto, hdrops);
619 /* ipn will now contain the inner IPv4 header */
620 m_copydata(m, skip, sizeof(struct ip), (caddr_t) &ipn);
623 * Check that the inner source address is the same as
624 * the proxy address, if available.
626 if ((saidx->proxy.sa.sa_family == AF_INET &&
627 saidx->proxy.sin.sin_addr.s_addr != INADDR_ANY &&
628 ipn.ip_src.s_addr != saidx->proxy.sin.sin_addr.s_addr) ||
629 (saidx->proxy.sa.sa_family != AF_INET &&
630 saidx->proxy.sa.sa_family != 0)) {
632 DPRINTF(("%s: inner source address %s doesn't "
633 "correspond to expected proxy source %s, "
634 "SA %s/%08lx\n", __func__,
635 inet_ntoa4(ipn.ip_src),
636 ipsec_address(&saidx->proxy),
637 ipsec_address(&saidx->dst),
638 (u_long) ntohl(sav->spi)));
640 IPSEC_ISTAT(sproto, pdrops);
647 /* IPv6-in-IP encapsulation */
648 if (prot == IPPROTO_IPV6) {
651 if (m->m_pkthdr.len - skip < sizeof(struct ip6_hdr)) {
652 IPSEC_ISTAT(sproto, hdrops);
656 /* ip6n will now contain the inner IPv6 header. */
657 m_copydata(m, skip, sizeof(struct ip6_hdr),
661 * Check that the inner source address is the same as
662 * the proxy address, if available.
664 if ((saidx->proxy.sa.sa_family == AF_INET6 &&
665 !IN6_IS_ADDR_UNSPECIFIED(&saidx->proxy.sin6.sin6_addr) &&
666 !IN6_ARE_ADDR_EQUAL(&ip6n.ip6_src,
667 &saidx->proxy.sin6.sin6_addr)) ||
668 (saidx->proxy.sa.sa_family != AF_INET6 &&
669 saidx->proxy.sa.sa_family != 0)) {
671 DPRINTF(("%s: inner source address %s doesn't "
672 "correspond to expected proxy source %s, "
673 "SA %s/%08lx\n", __func__,
674 ip6_sprintf(ip6buf, &ip6n.ip6_src),
675 ipsec_address(&saidx->proxy),
676 ipsec_address(&saidx->dst),
677 (u_long) ntohl(sav->spi)));
679 IPSEC_ISTAT(sproto, pdrops);
687 * Record what we've done to the packet (under what SA it was
688 * processed). If we've been passed an mtag, it means the packet
689 * was already processed by an ethernet/crypto combo card and
690 * thus has a tag attached with all the right information, but
691 * with a PACKET_TAG_IPSEC_IN_CRYPTO_DONE as opposed to
692 * PACKET_TAG_IPSEC_IN_DONE type; in that case, just change the type.
694 if (mt == NULL && sproto != IPPROTO_IPCOMP) {
695 mtag = m_tag_get(PACKET_TAG_IPSEC_IN_DONE,
696 sizeof(struct tdb_ident), M_NOWAIT);
698 DPRINTF(("%s: failed to get tag\n", __func__));
699 IPSEC_ISTAT(sproto, hdrops);
704 tdbi = (struct tdb_ident *)(mtag + 1);
705 bcopy(&saidx->dst, &tdbi->dst, sizeof(union sockaddr_union));
706 tdbi->proto = sproto;
707 tdbi->spi = sav->spi;
708 /* Cache those two for enc(4) in xform_ipip. */
709 tdbi->alg_auth = sav->alg_auth;
710 tdbi->alg_enc = sav->alg_enc;
712 m_tag_prepend(m, mtag);
715 mt->m_tag_id = PACKET_TAG_IPSEC_IN_DONE;
716 /* XXX do we need to mark m_flags??? */
719 key_sa_recordxfer(sav, m);
722 encif->if_ipackets++;
723 encif->if_ibytes += m->m_pkthdr.len;
726 * Pass the mbuf to enc0 for bpf and pfil. We will filter the IPIP
727 * packet later after it has been decapsulated.
729 ipsec_bpf(m, sav, AF_INET6, ENC_IN|ENC_BEFORE);
731 /* XXX-BZ does not make sense. */
732 if (prot != IPPROTO_IPIP)
733 if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_BEFORE)) != 0)
737 /* Retrieve new protocol */
738 m_copydata(m, protoff, sizeof(u_int8_t), (caddr_t) &nxt8);
741 * See the end of ip6_input for this logic.
742 * IPPROTO_IPV[46] case will be processed just like other ones
746 while (nxt != IPPROTO_DONE) {
747 if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) {
748 IP6STAT_INC(ip6s_toomanyhdr);
754 * Protection against faulty packet - there should be
755 * more sanity checks in header chain processing.
757 if (m->m_pkthdr.len < skip) {
758 IP6STAT_INC(ip6s_tooshort);
759 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);
764 * Enforce IPsec policy checking if we are seeing last header.
765 * note that we do not visit this with protocols with pcb layer
766 * code - like udp/tcp/raw ip.
768 if ((inet6sw[ip6_protox[nxt]].pr_flags & PR_LASTHDR) != 0 &&
769 ipsec6_in_reject(m, NULL)) {
773 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &skip, nxt);
783 esp6_ctlinput(int cmd, struct sockaddr *sa, void *d)
785 struct ip6ctlparam *ip6cp = NULL;
786 struct mbuf *m = NULL;
790 if (sa->sa_family != AF_INET6 ||
791 sa->sa_len != sizeof(struct sockaddr_in6))
793 if ((unsigned)cmd >= PRC_NCMDS)
796 /* if the parameter is from icmp6, decode it. */
798 ip6cp = (struct ip6ctlparam *)d;
800 ip6 = ip6cp->ip6c_ip6;
801 off = ip6cp->ip6c_off;
805 off = 0; /* calm gcc */
810 struct ip6ctlparam ip6cp1;
813 * Notify the error to all possible sockets via pfctlinput2.
814 * Since the upper layer information (such as protocol type,
815 * source and destination ports) is embedded in the encrypted
816 * data and might have been cut, we can't directly call
817 * an upper layer ctlinput function. However, the pcbnotify
818 * function will consider source and destination addresses
819 * as well as the flow info value, and may be able to find
820 * some PCB that should be notified.
821 * Although pfctlinput2 will call esp6_ctlinput(), there is
822 * no possibility of an infinite loop of function calls,
823 * because we don't pass the inner IPv6 header.
825 bzero(&ip6cp1, sizeof(ip6cp1));
826 ip6cp1.ip6c_src = ip6cp->ip6c_src;
827 pfctlinput2(cmd, sa, (void *)&ip6cp1);
830 * Then go to special cases that need ESP header information.
831 * XXX: We assume that when ip6 is non NULL,
832 * M and OFF are valid.
835 if (cmd == PRC_MSGSIZE) {
836 struct secasvar *sav;
840 /* check header length before using m_copydata */
841 if (m->m_pkthdr.len < off + sizeof (struct esp))
843 m_copydata(m, off + offsetof(struct esp, esp_spi),
844 sizeof(u_int32_t), (caddr_t) &spi);
846 * Check to see if we have a valid SA corresponding to
847 * the address in the ICMP message payload.
849 sav = KEY_ALLOCSA((union sockaddr_union *)sa,
851 valid = (sav != NULL);
855 /* XXX Further validation? */
858 * Depending on whether the SA is "valid" and
859 * routing table size (mtudisc_{hi,lo}wat), we will:
860 * - recalcurate the new MTU and create the
861 * corresponding routing entry, or
862 * - ignore the MTU change notification.
864 icmp6_mtudisc_update(ip6cp, valid);
867 /* we normally notify any pcb here */