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, isr_prot;
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);
332 * XXXGL: do we need this entire block?
334 if (m->m_len < skip && (m = m_pullup(m, skip)) == NULL) {
335 DPRINTF(("%s: processing failed for SA %s/%08lx\n",
336 __func__, ipsec_address(&sav->sah->saidx.dst),
337 (u_long) ntohl(sav->spi)));
338 IPSEC_ISTAT(sproto, hdrops);
343 ip = mtod(m, struct ip *);
344 ip->ip_len = htons(m->m_pkthdr.len);
346 ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
348 ip = mtod(m, struct ip *);
353 encif->if_ipackets++;
354 encif->if_ibytes += m->m_pkthdr.len;
356 /* Pass the mbuf to enc0 for bpf and pfil. */
357 ipsec_bpf(m, sav, AF_INET, ENC_IN|ENC_BEFORE);
358 if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_BEFORE)) != 0)
362 /* IP-in-IP encapsulation */
363 if (prot == IPPROTO_IPIP &&
364 saidx->mode != IPSEC_MODE_TRANSPORT) {
366 if (m->m_pkthdr.len - skip < sizeof(struct ip)) {
367 IPSEC_ISTAT(sproto, hdrops);
371 /* enc0: strip outer IPv4 header */
372 m_striphdr(m, 0, ip->ip_hl << 2);
375 /* XXX PROXY address isn't recorded in SAH */
377 * Check that the inner source address is the same as
378 * the proxy address, if available.
380 if ((saidx->proxy.sa.sa_family == AF_INET &&
381 saidx->proxy.sin.sin_addr.s_addr !=
384 saidx->proxy.sin.sin_addr.s_addr) ||
385 (saidx->proxy.sa.sa_family != AF_INET &&
386 saidx->proxy.sa.sa_family != 0)) {
388 DPRINTF(("%s: inner source address %s doesn't "
389 "correspond to expected proxy source %s, "
390 "SA %s/%08lx\n", __func__,
391 inet_ntoa4(ipn.ip_src),
392 ipsp_address(saidx->proxy),
393 ipsp_address(saidx->dst),
394 (u_long) ntohl(sav->spi)));
396 IPSEC_ISTAT(sproto, pdrops);
403 /* IPv6-in-IP encapsulation. */
404 else if (prot == IPPROTO_IPV6 &&
405 saidx->mode != IPSEC_MODE_TRANSPORT) {
407 if (m->m_pkthdr.len - skip < sizeof(struct ip6_hdr)) {
408 IPSEC_ISTAT(sproto, hdrops);
412 /* enc0: strip IPv4 header, keep IPv6 header only */
413 m_striphdr(m, 0, ip->ip_hl << 2);
416 * Check that the inner source address is the same as
417 * the proxy address, if available.
419 if ((saidx->proxy.sa.sa_family == AF_INET6 &&
420 !IN6_IS_ADDR_UNSPECIFIED(&saidx->proxy.sin6.sin6_addr) &&
421 !IN6_ARE_ADDR_EQUAL(&ip6n.ip6_src,
422 &saidx->proxy.sin6.sin6_addr)) ||
423 (saidx->proxy.sa.sa_family != AF_INET6 &&
424 saidx->proxy.sa.sa_family != 0)) {
426 DPRINTF(("%s: inner source address %s doesn't "
427 "correspond to expected proxy source %s, "
428 "SA %s/%08lx\n", __func__,
429 ip6_sprintf(ip6buf, &ip6n.ip6_src),
430 ipsec_address(&saidx->proxy),
431 ipsec_address(&saidx->dst),
432 (u_long) ntohl(sav->spi)));
434 IPSEC_ISTAT(sproto, pdrops);
441 else if (prot != IPPROTO_IPV6 && saidx->mode == IPSEC_MODE_ANY) {
443 * When mode is wildcard, inner protocol is IPv6 and
444 * we have no INET6 support - drop this packet a bit later.
445 * In other cases we assume transport mode and outer
446 * header was already stripped in xform_xxx_cb.
452 * Record what we've done to the packet (under what SA it was
453 * processed). If we've been passed an mtag, it means the packet
454 * was already processed by an ethernet/crypto combo card and
455 * thus has a tag attached with all the right information, but
456 * with a PACKET_TAG_IPSEC_IN_CRYPTO_DONE as opposed to
457 * PACKET_TAG_IPSEC_IN_DONE type; in that case, just change the type.
459 if (mt == NULL && sproto != IPPROTO_IPCOMP) {
460 mtag = m_tag_get(PACKET_TAG_IPSEC_IN_DONE,
461 sizeof(struct tdb_ident), M_NOWAIT);
463 DPRINTF(("%s: failed to get tag\n", __func__));
464 IPSEC_ISTAT(sproto, hdrops);
469 tdbi = (struct tdb_ident *)(mtag + 1);
470 bcopy(&saidx->dst, &tdbi->dst, saidx->dst.sa.sa_len);
471 tdbi->proto = sproto;
472 tdbi->spi = sav->spi;
473 /* Cache those two for enc(4) in xform_ipip. */
474 tdbi->alg_auth = sav->alg_auth;
475 tdbi->alg_enc = sav->alg_enc;
477 m_tag_prepend(m, mtag);
478 } else if (mt != NULL) {
479 mt->m_tag_id = PACKET_TAG_IPSEC_IN_DONE;
480 /* XXX do we need to mark m_flags??? */
483 key_sa_recordxfer(sav, m); /* record data transfer */
486 * In transport mode requeue decrypted mbuf back to IPv4 protocol
487 * handler. This is necessary to correctly expose rcvif.
489 if (saidx->mode == IPSEC_MODE_TRANSPORT)
493 * Pass the mbuf to enc0 for bpf and pfil.
495 if (prot == IPPROTO_IPIP)
496 ipsec_bpf(m, sav, AF_INET, ENC_IN|ENC_AFTER);
498 if (prot == IPPROTO_IPV6)
499 ipsec_bpf(m, sav, AF_INET6, ENC_IN|ENC_AFTER);
502 if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_AFTER)) != 0)
507 * Re-dispatch via software interrupt.
512 isr_prot = NETISR_IP;
516 isr_prot = NETISR_IPV6;
520 DPRINTF(("%s: cannot handle inner ip proto %d\n",
522 IPSEC_ISTAT(sproto, nopf);
523 error = EPFNOSUPPORT;
527 error = netisr_queue_src(isr_prot, (uintptr_t)sav->spi, m);
529 IPSEC_ISTAT(sproto, qfull);
530 DPRINTF(("%s: queue full; proto %u packet dropped\n",
541 ipsec4_common_ctlinput(int cmd, struct sockaddr *sa, void *v, int proto)
543 /* XXX nothing just yet */
548 /* IPv6 AH wrapper. */
550 ipsec6_common_input(struct mbuf **mp, int *offp, int proto)
556 if (*offp < sizeof(struct ip6_hdr)) {
557 DPRINTF(("%s: bad offset %u\n", __func__, *offp));
559 } else if (*offp == sizeof(struct ip6_hdr)) {
560 protoff = offsetof(struct ip6_hdr, ip6_nxt);
562 /* Chase down the header chain... */
563 protoff = sizeof(struct ip6_hdr);
567 m_copydata(*mp, protoff, sizeof(ip6e),
570 if (ip6e.ip6e_nxt == IPPROTO_AH)
571 l = (ip6e.ip6e_len + 2) << 2;
573 l = (ip6e.ip6e_len + 1) << 3;
574 IPSEC_ASSERT(l > 0, ("l went zero or negative"));
575 } while (protoff + l < *offp);
577 /* Malformed packet check */
578 if (protoff + l != *offp) {
579 DPRINTF(("%s: bad packet header chain, protoff %u, "
580 "l %u, off %u\n", __func__, protoff, l, *offp));
581 IPSEC_ISTAT(proto, hdrops);
586 protoff += offsetof(struct ip6_ext, ip6e_nxt);
588 (void) ipsec_common_input(*mp, *offp, protoff, AF_INET6, proto);
593 * IPsec input callback, called by the transform callback. Takes care of
594 * filtering and other sanity checks on the processed packet.
597 ipsec6_common_input_cb(struct mbuf *m, struct secasvar *sav, int skip, int protoff,
600 int prot, af, sproto;
603 struct tdb_ident *tdbi;
604 struct secasindex *saidx;
609 char ip6buf[INET6_ADDRSTRLEN];
612 IPSEC_ASSERT(m != NULL, ("null mbuf"));
613 IPSEC_ASSERT(sav != NULL, ("null SA"));
614 IPSEC_ASSERT(sav->sah != NULL, ("null SAH"));
615 saidx = &sav->sah->saidx;
616 af = saidx->dst.sa.sa_family;
617 IPSEC_ASSERT(af == AF_INET6, ("unexpected af %u", af));
618 sproto = saidx->proto;
619 IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH ||
620 sproto == IPPROTO_IPCOMP,
621 ("unexpected security protocol %u", sproto));
625 DPRINTF(("%s: null mbuf", __func__));
626 IPSEC_ISTAT(sproto, badkcr);
631 /* Fix IPv6 header */
632 if (m->m_len < sizeof(struct ip6_hdr) &&
633 (m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) {
635 DPRINTF(("%s: processing failed for SA %s/%08lx\n",
636 __func__, ipsec_address(&sav->sah->saidx.dst),
637 (u_long) ntohl(sav->spi)));
639 IPSEC_ISTAT(sproto, hdrops);
644 ip6 = mtod(m, struct ip6_hdr *);
645 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
648 m_copydata(m, protoff, 1, &nxt8);
652 encif->if_ipackets++;
653 encif->if_ibytes += m->m_pkthdr.len;
655 /* Pass the mbuf to enc0 for bpf and pfil. */
656 ipsec_bpf(m, sav, AF_INET6, ENC_IN|ENC_BEFORE);
657 if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_BEFORE)) != 0)
661 /* IPv6-in-IP encapsulation */
662 if (prot == IPPROTO_IPV6 &&
663 saidx->mode != IPSEC_MODE_TRANSPORT) {
664 if (m->m_pkthdr.len - skip < sizeof(struct ip6_hdr)) {
665 IPSEC_ISTAT(sproto, hdrops);
669 /* ip6n will now contain the inner IPv6 header. */
670 m_striphdr(m, 0, skip);
674 * Check that the inner source address is the same as
675 * the proxy address, if available.
677 if ((saidx->proxy.sa.sa_family == AF_INET6 &&
678 !IN6_IS_ADDR_UNSPECIFIED(&saidx->proxy.sin6.sin6_addr) &&
679 !IN6_ARE_ADDR_EQUAL(&ip6n.ip6_src,
680 &saidx->proxy.sin6.sin6_addr)) ||
681 (saidx->proxy.sa.sa_family != AF_INET6 &&
682 saidx->proxy.sa.sa_family != 0)) {
684 DPRINTF(("%s: inner source address %s doesn't "
685 "correspond to expected proxy source %s, "
686 "SA %s/%08lx\n", __func__,
687 ip6_sprintf(ip6buf, &ip6n.ip6_src),
688 ipsec_address(&saidx->proxy),
689 ipsec_address(&saidx->dst),
690 (u_long) ntohl(sav->spi)));
692 IPSEC_ISTAT(sproto, pdrops);
699 /* IP-in-IP encapsulation */
700 else if (prot == IPPROTO_IPIP &&
701 saidx->mode != IPSEC_MODE_TRANSPORT) {
702 if (m->m_pkthdr.len - skip < sizeof(struct ip)) {
703 IPSEC_ISTAT(sproto, hdrops);
707 /* ipn will now contain the inner IPv4 header */
708 m_striphdr(m, 0, skip);
712 * Check that the inner source address is the same as
713 * the proxy address, if available.
715 if ((saidx->proxy.sa.sa_family == AF_INET &&
716 saidx->proxy.sin.sin_addr.s_addr != INADDR_ANY &&
717 ipn.ip_src.s_addr != saidx->proxy.sin.sin_addr.s_addr) ||
718 (saidx->proxy.sa.sa_family != AF_INET &&
719 saidx->proxy.sa.sa_family != 0)) {
721 DPRINTF(("%s: inner source address %s doesn't "
722 "correspond to expected proxy source %s, "
723 "SA %s/%08lx\n", __func__,
724 inet_ntoa4(ipn.ip_src),
725 ipsec_address(&saidx->proxy),
726 ipsec_address(&saidx->dst),
727 (u_long) ntohl(sav->spi)));
729 IPSEC_ISTAT(sproto, pdrops);
737 prot = IPPROTO_IPV6; /* for correct BPF processing */
741 * Record what we've done to the packet (under what SA it was
742 * processed). If we've been passed an mtag, it means the packet
743 * was already processed by an ethernet/crypto combo card and
744 * thus has a tag attached with all the right information, but
745 * with a PACKET_TAG_IPSEC_IN_CRYPTO_DONE as opposed to
746 * PACKET_TAG_IPSEC_IN_DONE type; in that case, just change the type.
748 if (mt == NULL && sproto != IPPROTO_IPCOMP) {
749 mtag = m_tag_get(PACKET_TAG_IPSEC_IN_DONE,
750 sizeof(struct tdb_ident), M_NOWAIT);
752 DPRINTF(("%s: failed to get tag\n", __func__));
753 IPSEC_ISTAT(sproto, hdrops);
758 tdbi = (struct tdb_ident *)(mtag + 1);
759 bcopy(&saidx->dst, &tdbi->dst, sizeof(union sockaddr_union));
760 tdbi->proto = sproto;
761 tdbi->spi = sav->spi;
762 /* Cache those two for enc(4) in xform_ipip. */
763 tdbi->alg_auth = sav->alg_auth;
764 tdbi->alg_enc = sav->alg_enc;
766 m_tag_prepend(m, mtag);
769 mt->m_tag_id = PACKET_TAG_IPSEC_IN_DONE;
770 /* XXX do we need to mark m_flags??? */
773 key_sa_recordxfer(sav, m);
777 * Pass the mbuf to enc0 for bpf and pfil.
780 if (prot == IPPROTO_IPIP)
781 ipsec_bpf(m, sav, AF_INET, ENC_IN|ENC_AFTER);
783 if (prot == IPPROTO_IPV6)
784 ipsec_bpf(m, sav, AF_INET6, ENC_IN|ENC_AFTER);
786 if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_AFTER)) != 0)
790 * See the end of ip6_input for this logic.
791 * IPPROTO_IPV[46] case will be processed just like other ones
795 while (nxt != IPPROTO_DONE) {
796 if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) {
797 IP6STAT_INC(ip6s_toomanyhdr);
803 * Protection against faulty packet - there should be
804 * more sanity checks in header chain processing.
806 if (m->m_pkthdr.len < skip) {
807 IP6STAT_INC(ip6s_tooshort);
808 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);
813 * Enforce IPsec policy checking if we are seeing last header.
814 * note that we do not visit this with protocols with pcb layer
815 * code - like udp/tcp/raw ip.
817 if ((inet6sw[ip6_protox[nxt]].pr_flags & PR_LASTHDR) != 0 &&
818 ipsec6_in_reject(m, NULL)) {
822 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &skip, nxt);
832 esp6_ctlinput(int cmd, struct sockaddr *sa, void *d)
834 struct ip6ctlparam *ip6cp = NULL;
835 struct mbuf *m = NULL;
839 if (sa->sa_family != AF_INET6 ||
840 sa->sa_len != sizeof(struct sockaddr_in6))
842 if ((unsigned)cmd >= PRC_NCMDS)
845 /* if the parameter is from icmp6, decode it. */
847 ip6cp = (struct ip6ctlparam *)d;
849 ip6 = ip6cp->ip6c_ip6;
850 off = ip6cp->ip6c_off;
854 off = 0; /* calm gcc */
859 struct ip6ctlparam ip6cp1;
862 * Notify the error to all possible sockets via pfctlinput2.
863 * Since the upper layer information (such as protocol type,
864 * source and destination ports) is embedded in the encrypted
865 * data and might have been cut, we can't directly call
866 * an upper layer ctlinput function. However, the pcbnotify
867 * function will consider source and destination addresses
868 * as well as the flow info value, and may be able to find
869 * some PCB that should be notified.
870 * Although pfctlinput2 will call esp6_ctlinput(), there is
871 * no possibility of an infinite loop of function calls,
872 * because we don't pass the inner IPv6 header.
874 bzero(&ip6cp1, sizeof(ip6cp1));
875 ip6cp1.ip6c_src = ip6cp->ip6c_src;
876 pfctlinput2(cmd, sa, (void *)&ip6cp1);
879 * Then go to special cases that need ESP header information.
880 * XXX: We assume that when ip6 is non NULL,
881 * M and OFF are valid.
884 if (cmd == PRC_MSGSIZE) {
885 struct secasvar *sav;
889 /* check header length before using m_copydata */
890 if (m->m_pkthdr.len < off + sizeof (struct esp))
892 m_copydata(m, off + offsetof(struct esp, esp_spi),
893 sizeof(u_int32_t), (caddr_t) &spi);
895 * Check to see if we have a valid SA corresponding to
896 * the address in the ICMP message payload.
898 sav = KEY_ALLOCSA((union sockaddr_union *)sa,
900 valid = (sav != NULL);
904 /* XXX Further validation? */
907 * Depending on whether the SA is "valid" and
908 * routing table size (mtudisc_{hi,lo}wat), we will:
909 * - recalcurate the new MTU and create the
910 * corresponding routing entry, or
911 * - ignore the MTU change notification.
913 icmp6_mtudisc_update(ip6cp, valid);
916 /* we normally notify any pcb here */