1 /* $FreeBSD: src/sys/netipsec/xform_ah.c,v 1.1.4.2 2003/02/26 00:14:05 sam Exp $ */
2 /* $DragonFly: src/sys/netproto/ipsec/xform_ah.c,v 1.8 2005/06/17 19:12:23 dillon Exp $ */
3 /* $OpenBSD: ip_ah.c,v 1.63 2001/06/26 06:18:58 angelos Exp $ */
5 * The authors of this code are John Ioannidis (ji@tla.org),
6 * Angelos D. Keromytis (kermit@csd.uch.gr) and
7 * Niels Provos (provos@physnet.uni-hamburg.de).
9 * The original version of this code was written by John Ioannidis
10 * for BSD/OS in Athens, Greece, in November 1995.
12 * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
13 * by Angelos D. Keromytis.
15 * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis
18 * Additional features in 1999 by Angelos D. Keromytis and Niklas Hallqvist.
20 * Copyright (c) 1995, 1996, 1997, 1998, 1999 by John Ioannidis,
21 * Angelos D. Keromytis and Niels Provos.
22 * Copyright (c) 1999 Niklas Hallqvist.
23 * Copyright (c) 2001 Angelos D. Keromytis.
25 * Permission to use, copy, and modify this software with or without fee
26 * is hereby granted, provided that this entire notice is included in
27 * all copies of any software which is or includes a copy or
28 * modification of this software.
29 * You may use this code under the GNU public license if you so wish. Please
30 * contribute changes back to the authors under this freer than GPL license
31 * so that we may further the use of strong encryption without limitations to
34 * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
35 * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
36 * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
37 * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
41 #include "opt_inet6.h"
43 #include <sys/param.h>
44 #include <sys/systm.h>
46 #include <sys/socket.h>
47 #include <sys/syslog.h>
48 #include <sys/kernel.h>
49 #include <sys/sysctl.h>
53 #include <netinet/in.h>
54 #include <netinet/in_systm.h>
55 #include <netinet/ip.h>
56 #include <netinet/ip_ecn.h>
57 #include <netinet/ip6.h>
59 #include <net/route.h>
60 #include <netproto/ipsec/ipsec.h>
61 #include <netproto/ipsec/ah.h>
62 #include <netproto/ipsec/ah_var.h>
63 #include <netproto/ipsec/xform.h>
66 #include <netinet6/ip6_var.h>
67 #include <netproto/ipsec/ipsec6.h>
68 #include <netinet6/ip6_ecn.h>
71 #include <netproto/ipsec/key.h>
72 #include <netproto/ipsec/key_debug.h>
74 #include <opencrypto/cryptodev.h>
77 * Return header size in bytes. The old protocol did not support
78 * the replay counter; the new protocol always includes the counter.
80 #define HDRSIZE(sav) \
81 (((sav)->flags & SADB_X_EXT_OLD) ? \
82 sizeof (struct ah) : sizeof (struct ah) + sizeof (u_int32_t))
84 * Return authenticator size in bytes. The old protocol is known
85 * to use a fixed 16-byte authenticator. The new algorithm gets
86 * this size from the xform but is (currently) always 12.
88 #define AUTHSIZE(sav) \
89 ((sav->flags & SADB_X_EXT_OLD) ? 16 : (sav)->tdb_authalgxform->authsize)
91 int ah_enable = 1; /* control flow of packets with AH */
92 int ah_cleartos = 1; /* clear ip_tos when doing AH calc */
95 SYSCTL_DECL(_net_inet_ah);
96 SYSCTL_INT(_net_inet_ah, OID_AUTO,
97 ah_enable, CTLFLAG_RW, &ah_enable, 0, "");
98 SYSCTL_INT(_net_inet_ah, OID_AUTO,
99 ah_cleartos, CTLFLAG_RW, &ah_cleartos, 0, "");
100 SYSCTL_STRUCT(_net_inet_ah, IPSECCTL_STATS,
101 stats, CTLFLAG_RD, &ahstat, ahstat, "");
103 static unsigned char ipseczeroes[256]; /* larger than an ip6 extension hdr */
105 static int ah_input_cb(struct cryptop*);
106 static int ah_output_cb(struct cryptop*);
109 * NB: this is public for use by the PF_KEY support.
112 ah_algorithm_lookup(int alg)
114 if (alg >= AH_ALG_MAX)
117 case SADB_X_AALG_NULL:
118 return &auth_hash_null;
119 case SADB_AALG_MD5HMAC:
120 return &auth_hash_hmac_md5_96;
121 case SADB_AALG_SHA1HMAC:
122 return &auth_hash_hmac_sha1_96;
123 case SADB_X_AALG_RIPEMD160HMAC:
124 return &auth_hash_hmac_ripemd_160_96;
125 case SADB_X_AALG_MD5:
126 return &auth_hash_key_md5;
127 case SADB_X_AALG_SHA:
128 return &auth_hash_key_sha1;
129 case SADB_X_AALG_SHA2_256:
130 return &auth_hash_hmac_sha2_256;
131 case SADB_X_AALG_SHA2_384:
132 return &auth_hash_hmac_sha2_384;
133 case SADB_X_AALG_SHA2_512:
134 return &auth_hash_hmac_sha2_512;
140 ah_hdrsiz(struct secasvar *sav)
146 KASSERT(sav->tdb_authalgxform != NULL,
147 ("ah_hdrsiz: null xform"));
148 /*XXX not right for null algorithm--does it matter??*/
149 authsize = AUTHSIZE(sav);
150 size = roundup(authsize, sizeof (u_int32_t)) + HDRSIZE(sav);
153 size = sizeof (struct ah) + sizeof (u_int32_t) + 16;
159 * NB: public for use by esp_init.
162 ah_init0(struct secasvar *sav, struct xformsw *xsp, struct cryptoini *cria)
164 struct auth_hash *thash;
167 thash = ah_algorithm_lookup(sav->alg_auth);
169 DPRINTF(("ah_init: unsupported authentication algorithm %u\n",
174 * Verify the replay state block allocation is consistent with
175 * the protocol type. We check here so we can make assumptions
176 * later during protocol processing.
178 /* NB: replay state is setup elsewhere (sigh) */
179 if (((sav->flags&SADB_X_EXT_OLD) == 0) ^ (sav->replay != NULL)) {
180 DPRINTF(("ah_init: replay state block inconsistency, "
181 "%s algorithm %s replay state\n",
182 (sav->flags & SADB_X_EXT_OLD) ? "old" : "new",
183 sav->replay == NULL ? "without" : "with"));
186 if (sav->key_auth == NULL) {
187 DPRINTF(("ah_init: no authentication key for %s "
188 "algorithm\n", thash->name));
191 keylen = _KEYLEN(sav->key_auth);
192 if (keylen != thash->keysize && thash->keysize != 0) {
193 DPRINTF(("ah_init: invalid keylength %d, algorithm "
194 "%s requires keysize %d\n",
195 keylen, thash->name, thash->keysize));
199 sav->tdb_xform = xsp;
200 sav->tdb_authalgxform = thash;
202 /* Initialize crypto session. */
203 bzero(cria, sizeof (*cria));
204 cria->cri_alg = sav->tdb_authalgxform->type;
205 cria->cri_klen = _KEYBITS(sav->key_auth);
206 cria->cri_key = _KEYBUF(sav->key_auth);
212 * ah_init() is called when an SPI is being set up.
215 ah_init(struct secasvar *sav, struct xformsw *xsp)
217 struct cryptoini cria;
220 error = ah_init0(sav, xsp, &cria);
221 return error ? error :
222 crypto_newsession(&sav->tdb_cryptoid, &cria, crypto_support);
228 * NB: public for use by esp_zeroize (XXX).
231 ah_zeroize(struct secasvar *sav)
236 bzero(_KEYBUF(sav->key_auth), _KEYLEN(sav->key_auth));
238 err = crypto_freesession(sav->tdb_cryptoid);
239 sav->tdb_cryptoid = 0;
240 sav->tdb_authalgxform = NULL;
241 sav->tdb_xform = NULL;
246 * Massage IPv4/IPv6 headers for AH processing.
249 ah_massage_headers(struct mbuf **m0, int proto, int skip, int alg, int out)
251 struct mbuf *m = *m0;
260 struct ip6_ext *ip6e;
269 * This is the least painful way of dealing with IPv4 header
270 * and option processing -- just make sure they're in
273 *m0 = m = m_pullup(m, skip);
275 DPRINTF(("ah_massage_headers: m_pullup failed\n"));
279 /* Fix the IP header */
280 ip = mtod(m, struct ip *);
287 * On input, fix ip_len which has been byte-swapped
291 ip->ip_len = htons(ip->ip_len + skip);
293 if (alg == CRYPTO_MD5_KPDK || alg == CRYPTO_SHA1_KPDK)
294 ip->ip_off = htons(ip->ip_off & IP_DF);
298 if (alg == CRYPTO_MD5_KPDK || alg == CRYPTO_SHA1_KPDK)
299 ip->ip_off = htons(ntohs(ip->ip_off) & IP_DF);
304 ptr = mtod(m, unsigned char *) + sizeof(struct ip);
306 /* IPv4 option processing */
307 for (off = sizeof(struct ip); off < skip;) {
308 if (ptr[off] == IPOPT_EOL || ptr[off] == IPOPT_NOP ||
312 DPRINTF(("ah_massage_headers: illegal IPv4 "
313 "option length for option %d\n",
322 off = skip; /* End the loop. */
329 case IPOPT_SECURITY: /* 0x82 */
330 case 0x85: /* Extended security. */
331 case 0x86: /* Commercial security. */
332 case 0x94: /* Router alert */
333 case 0x95: /* RFC1770 */
334 /* Sanity check for option length. */
335 if (ptr[off + 1] < 2) {
336 DPRINTF(("ah_massage_headers: "
337 "illegal IPv4 option length for "
338 "option %d\n", ptr[off]));
349 /* Sanity check for option length. */
350 if (ptr[off + 1] < 2) {
351 DPRINTF(("ah_massage_headers: "
352 "illegal IPv4 option length for "
353 "option %d\n", ptr[off]));
360 * On output, if we have either of the
361 * source routing options, we should
362 * swap the destination address of the
363 * IP header with the last address
364 * specified in the option, as that is
365 * what the destination's IP header
369 bcopy(ptr + off + ptr[off + 1] -
370 sizeof(struct in_addr),
371 &(ip->ip_dst), sizeof(struct in_addr));
375 /* Sanity check for option length. */
376 if (ptr[off + 1] < 2) {
377 DPRINTF(("ah_massage_headers: "
378 "illegal IPv4 option length for "
379 "option %d\n", ptr[off]));
384 /* Zeroize all other options. */
385 count = ptr[off + 1];
386 bcopy(ipseczeroes, ptr, count);
393 DPRINTF(("ah_massage_headers(): malformed "
394 "IPv4 options header\n"));
405 case AF_INET6: /* Ugly... */
406 /* Copy and "cook" the IPv6 header. */
407 m_copydata(m, 0, sizeof(ip6), (caddr_t) &ip6);
409 /* We don't do IPv6 Jumbograms. */
410 if (ip6.ip6_plen == 0) {
411 DPRINTF(("ah_massage_headers: unsupported IPv6 jumbogram\n"));
418 ip6.ip6_vfc &= ~IPV6_VERSION_MASK;
419 ip6.ip6_vfc |= IPV6_VERSION;
421 /* Scoped address handling. */
422 if (IN6_IS_SCOPE_LINKLOCAL(&ip6.ip6_src))
423 ip6.ip6_src.s6_addr16[1] = 0;
424 if (IN6_IS_SCOPE_LINKLOCAL(&ip6.ip6_dst))
425 ip6.ip6_dst.s6_addr16[1] = 0;
427 /* Done with IPv6 header. */
428 m_copyback(m, 0, sizeof(struct ip6_hdr), (caddr_t) &ip6);
430 /* Let's deal with the remaining headers (if any). */
431 if (skip - sizeof(struct ip6_hdr) > 0) {
432 if (m->m_len <= skip) {
433 ptr = malloc(skip - sizeof(struct ip6_hdr),
434 M_XDATA, M_INTWAIT | M_NULLOK);
436 DPRINTF(("ah_massage_headers: failed "
437 "to allocate memory for IPv6 "
444 * Copy all the protocol headers after
447 m_copydata(m, sizeof(struct ip6_hdr),
448 skip - sizeof(struct ip6_hdr), ptr);
451 /* No need to allocate memory. */
452 ptr = mtod(m, unsigned char *) +
453 sizeof(struct ip6_hdr);
459 off = ip6.ip6_nxt & 0xff; /* Next header type. */
461 for (len = 0; len < skip - sizeof(struct ip6_hdr);)
463 case IPPROTO_HOPOPTS:
464 case IPPROTO_DSTOPTS:
465 ip6e = (struct ip6_ext *) (ptr + len);
468 * Process the mutable/immutable
469 * options -- borrows heavily from the
472 for (count = len + sizeof(struct ip6_ext);
473 count < len + ((ip6e->ip6e_len + 1) << 3);) {
474 if (ptr[count] == IP6OPT_PAD1) {
476 continue; /* Skip padding. */
481 ((ip6e->ip6e_len + 1) << 3)) {
484 /* Free, if we allocated. */
492 /* If mutable option, zeroize. */
493 if (ptr[count] & IP6OPT_MUTABLE)
494 bcopy(ipseczeroes, ptr + count,
501 skip - sizeof(struct ip6_hdr)) {
504 /* Free, if we allocated. */
512 len += ((ip6e->ip6e_len + 1) << 3);
513 off = ip6e->ip6e_nxt;
516 case IPPROTO_ROUTING:
518 * Always include routing headers in
521 ip6e = (struct ip6_ext *) (ptr + len);
522 len += ((ip6e->ip6e_len + 1) << 3);
523 off = ip6e->ip6e_nxt;
527 DPRINTF(("ah_massage_headers: unexpected "
528 "IPv6 header type %d", off));
535 /* Copyback and free, if we allocated. */
537 m_copyback(m, sizeof(struct ip6_hdr),
538 skip - sizeof(struct ip6_hdr), ptr);
550 * ah_input() gets called to verify that an input packet
551 * passes authentication.
554 ah_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff)
556 struct auth_hash *ahx;
557 struct tdb_ident *tdbi;
558 struct tdb_crypto *tc;
561 int hl, rplen, authsize;
563 struct cryptodesc *crda;
566 KASSERT(sav != NULL, ("ah_input: null SA"));
567 KASSERT(sav->key_auth != NULL,
568 ("ah_input: null authentication key"));
569 KASSERT(sav->tdb_authalgxform != NULL,
570 ("ah_input: null authentication xform"));
572 /* Figure out header size. */
573 rplen = HDRSIZE(sav);
575 /* XXX don't pullup, just copy header */
576 IP6_EXTHDR_GET(ah, struct newah *, m, skip, rplen);
578 DPRINTF(("ah_input: cannot pullup header\n"));
579 ahstat.ahs_hdrops++; /*XXX*/
584 /* Check replay window, if applicable. */
585 if (sav->replay && !ipsec_chkreplay(ntohl(ah->ah_seq), sav)) {
587 DPRINTF(("ah_input: packet replay failure: %s\n",
588 ipsec_logsastr(sav)));
593 /* Verify AH header length. */
594 hl = ah->ah_len * sizeof (u_int32_t);
595 ahx = sav->tdb_authalgxform;
596 authsize = AUTHSIZE(sav);
597 if (hl != authsize + rplen - sizeof (struct ah)) {
598 DPRINTF(("ah_input: bad authenticator length %u (expecting %lu)"
599 " for packet in SA %s/%08lx\n",
600 hl, (u_long) (authsize + rplen - sizeof (struct ah)),
601 ipsec_address(&sav->sah->saidx.dst),
602 (u_long) ntohl(sav->spi)));
603 ahstat.ahs_badauthl++;
607 ahstat.ahs_ibytes += m->m_pkthdr.len - skip - hl;
609 /* Get crypto descriptors. */
610 crp = crypto_getreq(1);
612 DPRINTF(("ah_input: failed to acquire crypto descriptor\n"));
618 crda = crp->crp_desc;
619 KASSERT(crda != NULL, ("ah_input: null crypto descriptor"));
622 crda->crd_len = m->m_pkthdr.len;
623 crda->crd_inject = skip + rplen;
625 /* Authentication operation. */
626 crda->crd_alg = ahx->type;
627 crda->crd_key = _KEYBUF(sav->key_auth);
628 crda->crd_klen = _KEYBITS(sav->key_auth);
630 /* Find out if we've already done crypto. */
631 for (mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_CRYPTO_DONE, NULL);
633 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_CRYPTO_DONE, mtag)) {
634 tdbi = (struct tdb_ident *)m_tag_data(mtag);
635 if (tdbi->proto == sav->sah->saidx.proto &&
636 tdbi->spi == sav->spi &&
637 !bcmp(&tdbi->dst, &sav->sah->saidx.dst,
638 sizeof (union sockaddr_union)))
642 /* Allocate IPsec-specific opaque crypto info. */
644 tc = malloc(sizeof (struct tdb_crypto) +
645 skip + rplen + authsize, M_XDATA,
646 M_INTWAIT | M_ZERO | M_NULLOK);
648 /* Hash verification has already been done successfully. */
649 tc = malloc(sizeof (struct tdb_crypto),
650 M_XDATA, M_INTWAIT | M_ZERO | M_NULLOK);
653 DPRINTF(("ah_input: failed to allocate tdb_crypto\n"));
660 /* Only save information if crypto processing is needed. */
665 * Save the authenticator, the skipped portion of the packet,
668 m_copydata(m, 0, skip + rplen + authsize, (caddr_t)(tc+1));
670 /* Zeroize the authenticator on the packet. */
671 m_copyback(m, skip + rplen, authsize, ipseczeroes);
673 /* "Massage" the packet headers for crypto processing. */
674 error = ah_massage_headers(&m, sav->sah->saidx.dst.sa.sa_family,
677 /* NB: mbuf is free'd by ah_massage_headers */
685 /* Crypto operation descriptor. */
686 crp->crp_ilen = m->m_pkthdr.len; /* Total input length. */
687 crp->crp_flags = CRYPTO_F_IMBUF;
688 crp->crp_buf = (caddr_t) m;
689 crp->crp_callback = ah_input_cb;
690 crp->crp_sid = sav->tdb_cryptoid;
691 crp->crp_opaque = (caddr_t) tc;
693 /* These are passed as-is to the callback. */
694 tc->tc_spi = sav->spi;
695 tc->tc_dst = sav->sah->saidx.dst;
696 tc->tc_proto = sav->sah->saidx.proto;
697 tc->tc_nxt = ah->ah_nxt;
698 tc->tc_protoff = protoff;
700 tc->tc_ptr = (caddr_t) mtag; /* Save the mtag we've identified. */
703 return crypto_dispatch(crp);
705 return ah_input_cb(crp);
709 #define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag) do { \
710 if (saidx->dst.sa.sa_family == AF_INET6) { \
711 error = ipsec6_common_input_cb(m, sav, skip, protoff, mtag); \
713 error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag); \
717 #define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag) \
718 (error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag))
722 * AH input callback from the crypto driver.
725 ah_input_cb(struct cryptop *crp)
727 int rplen, error, skip, protoff;
728 unsigned char calc[AH_ALEN_MAX];
730 struct cryptodesc *crd;
731 struct auth_hash *ahx;
732 struct tdb_crypto *tc;
734 struct secasvar *sav;
735 struct secasindex *saidx;
742 tc = (struct tdb_crypto *) crp->crp_opaque;
743 KASSERT(tc != NULL, ("ah_input_cb: null opaque crypto data area!"));
746 protoff = tc->tc_protoff;
747 mtag = (struct m_tag *) tc->tc_ptr;
748 m = (struct mbuf *) crp->crp_buf;
752 sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi);
755 DPRINTF(("ah_input_cb: SA expired while in crypto\n"));
756 error = ENOBUFS; /*XXX*/
760 saidx = &sav->sah->saidx;
761 KASSERT(saidx->dst.sa.sa_family == AF_INET ||
762 saidx->dst.sa.sa_family == AF_INET6,
763 ("ah_input_cb: unexpected protocol family %u",
764 saidx->dst.sa.sa_family));
766 ahx = (struct auth_hash *) sav->tdb_authalgxform;
768 /* Check for crypto errors. */
769 if (crp->crp_etype) {
770 if (sav->tdb_cryptoid != 0)
771 sav->tdb_cryptoid = crp->crp_sid;
773 if (crp->crp_etype == EAGAIN)
774 return crypto_dispatch(crp);
776 ahstat.ahs_noxform++;
777 DPRINTF(("ah_input_cb: crypto error %d\n", crp->crp_etype));
778 error = crp->crp_etype;
781 ahstat.ahs_hist[sav->alg_auth]++;
782 crypto_freereq(crp); /* No longer needed. */
786 /* Shouldn't happen... */
789 DPRINTF(("ah_input_cb: bogus returned buffer from crypto\n"));
794 /* Figure out header size. */
795 rplen = HDRSIZE(sav);
796 authsize = AUTHSIZE(sav);
798 /* Copy authenticator off the packet. */
799 m_copydata(m, skip + rplen, authsize, calc);
802 * If we have an mtag, we don't need to verify the authenticator --
803 * it has been verified by an IPsec-aware NIC.
806 ptr = (caddr_t) (tc + 1);
808 /* Verify authenticator. */
809 if (bcmp(ptr + skip + rplen, calc, authsize)) {
810 DPRINTF(("ah_input: authentication hash mismatch "
811 "for packet in SA %s/%08lx\n",
812 ipsec_address(&saidx->dst),
813 (u_long) ntohl(sav->spi)));
814 ahstat.ahs_badauth++;
819 /* Fix the Next Protocol field. */
820 ((u_int8_t *) ptr)[protoff] = nxt;
822 /* Copyback the saved (uncooked) network headers. */
823 m_copyback(m, 0, skip, ptr);
825 /* Fix the Next Protocol field. */
826 m_copyback(m, protoff, sizeof(u_int8_t), &nxt);
829 free(tc, M_XDATA), tc = NULL; /* No longer needed */
832 * Header is now authenticated.
834 m->m_flags |= M_AUTHIPHDR|M_AUTHIPDGM;
837 * Update replay sequence number, if appropriate.
842 m_copydata(m, skip + offsetof(struct newah, ah_seq),
843 sizeof (seq), (caddr_t) &seq);
844 if (ipsec_updatereplay(ntohl(seq), sav)) {
846 error = ENOBUFS; /*XXX as above*/
852 * Remove the AH header and authenticator from the mbuf.
854 error = m_striphdr(m, skip, rplen + authsize);
856 DPRINTF(("ah_input_cb: mangled mbuf chain for SA %s/%08lx\n",
857 ipsec_address(&saidx->dst), (u_long) ntohl(sav->spi)));
863 IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag);
882 * AH output routine, called by ipsec[46]_process_packet().
887 struct ipsecrequest *isr,
892 struct secasvar *sav;
893 struct auth_hash *ahx;
894 struct cryptodesc *crda;
895 struct tdb_crypto *tc;
899 int error, rplen, authsize, maxpacketsize, roff;
904 KASSERT(sav != NULL, ("ah_output: null SA"));
905 ahx = sav->tdb_authalgxform;
906 KASSERT(ahx != NULL, ("ah_output: null authentication xform"));
910 /* Figure out header size. */
911 rplen = HDRSIZE(sav);
913 /* Check for maximum packet size violations. */
914 switch (sav->sah->saidx.dst.sa.sa_family) {
917 maxpacketsize = IP_MAXPACKET;
922 maxpacketsize = IPV6_MAXPACKET;
926 DPRINTF(("ah_output: unknown/unsupported protocol "
927 "family %u, SA %s/%08lx\n",
928 sav->sah->saidx.dst.sa.sa_family,
929 ipsec_address(&sav->sah->saidx.dst),
930 (u_long) ntohl(sav->spi)));
932 error = EPFNOSUPPORT;
935 authsize = AUTHSIZE(sav);
936 if (rplen + authsize + m->m_pkthdr.len > maxpacketsize) {
937 DPRINTF(("ah_output: packet in SA %s/%08lx got too big "
938 "(len %u, max len %u)\n",
939 ipsec_address(&sav->sah->saidx.dst),
940 (u_long) ntohl(sav->spi),
941 rplen + authsize + m->m_pkthdr.len, maxpacketsize));
947 /* Update the counters. */
948 ahstat.ahs_obytes += m->m_pkthdr.len - skip;
952 DPRINTF(("ah_output: cannot clone mbuf chain, SA %s/%08lx\n",
953 ipsec_address(&sav->sah->saidx.dst),
954 (u_long) ntohl(sav->spi)));
960 /* Inject AH header. */
961 mi = m_makespace(m, skip, rplen + authsize, &roff);
963 DPRINTF(("ah_output: failed to inject %u byte AH header for SA "
966 ipsec_address(&sav->sah->saidx.dst),
967 (u_long) ntohl(sav->spi)));
968 ahstat.ahs_hdrops++; /*XXX differs from openbsd */
974 * The AH header is guaranteed by m_makespace() to be in
975 * contiguous memory, at roff bytes offset into the returned mbuf.
977 ah = (struct newah *)(mtod(mi, caddr_t) + roff);
979 /* Initialize the AH header. */
980 m_copydata(m, protoff, sizeof(u_int8_t), (caddr_t) &ah->ah_nxt);
981 ah->ah_len = (rplen + authsize - sizeof(struct ah)) / sizeof(u_int32_t);
983 ah->ah_spi = sav->spi;
985 /* Zeroize authenticator. */
986 m_copyback(m, skip + rplen, authsize, ipseczeroes);
988 /* Insert packet replay counter, as requested. */
990 if (sav->replay->count == ~0 &&
991 (sav->flags & SADB_X_EXT_CYCSEQ) == 0) {
992 DPRINTF(("ah_output: replay counter wrapped for SA "
994 ipsec_address(&sav->sah->saidx.dst),
995 (u_long) ntohl(sav->spi)));
1000 sav->replay->count++;
1001 ah->ah_seq = htonl(sav->replay->count);
1004 /* Get crypto descriptors. */
1005 crp = crypto_getreq(1);
1007 DPRINTF(("ah_output: failed to acquire crypto descriptors\n"));
1008 ahstat.ahs_crypto++;
1013 crda = crp->crp_desc;
1016 crda->crd_inject = skip + rplen;
1017 crda->crd_len = m->m_pkthdr.len;
1019 /* Authentication operation. */
1020 crda->crd_alg = ahx->type;
1021 crda->crd_key = _KEYBUF(sav->key_auth);
1022 crda->crd_klen = _KEYBITS(sav->key_auth);
1024 /* Allocate IPsec-specific opaque crypto info. */
1025 tc = malloc(sizeof(struct tdb_crypto) + skip, M_XDATA,
1026 M_INTWAIT | M_ZERO | M_NULLOK);
1028 crypto_freereq(crp);
1029 DPRINTF(("ah_output: failed to allocate tdb_crypto\n"));
1030 ahstat.ahs_crypto++;
1035 /* Save the skipped portion of the packet. */
1036 m_copydata(m, 0, skip, (caddr_t) (tc + 1));
1039 * Fix IP header length on the header used for
1040 * authentication. We don't need to fix the original
1041 * header length as it will be fixed by our caller.
1043 switch (sav->sah->saidx.dst.sa.sa_family) {
1046 bcopy(((caddr_t)(tc + 1)) +
1047 offsetof(struct ip, ip_len),
1048 (caddr_t) &iplen, sizeof(u_int16_t));
1049 iplen = htons(ntohs(iplen) + rplen + authsize);
1050 m_copyback(m, offsetof(struct ip, ip_len),
1051 sizeof(u_int16_t), (caddr_t) &iplen);
1057 bcopy(((caddr_t)(tc + 1)) +
1058 offsetof(struct ip6_hdr, ip6_plen),
1059 (caddr_t) &iplen, sizeof(u_int16_t));
1060 iplen = htons(ntohs(iplen) + rplen + authsize);
1061 m_copyback(m, offsetof(struct ip6_hdr, ip6_plen),
1062 sizeof(u_int16_t), (caddr_t) &iplen);
1067 /* Fix the Next Header field in saved header. */
1068 ((u_int8_t *) (tc + 1))[protoff] = IPPROTO_AH;
1070 /* Update the Next Protocol field in the IP header. */
1072 m_copyback(m, protoff, sizeof(u_int8_t), (caddr_t) &prot);
1074 /* "Massage" the packet headers for crypto processing. */
1075 error = ah_massage_headers(&m, sav->sah->saidx.dst.sa.sa_family,
1076 skip, ahx->type, 1);
1078 m = NULL; /* mbuf was free'd by ah_massage_headers. */
1080 crypto_freereq(crp);
1084 /* Crypto operation descriptor. */
1085 crp->crp_ilen = m->m_pkthdr.len; /* Total input length. */
1086 crp->crp_flags = CRYPTO_F_IMBUF;
1087 crp->crp_buf = (caddr_t) m;
1088 crp->crp_callback = ah_output_cb;
1089 crp->crp_sid = sav->tdb_cryptoid;
1090 crp->crp_opaque = (caddr_t) tc;
1092 /* These are passed as-is to the callback. */
1094 tc->tc_spi = sav->spi;
1095 tc->tc_dst = sav->sah->saidx.dst;
1096 tc->tc_proto = sav->sah->saidx.proto;
1098 tc->tc_protoff = protoff;
1100 return crypto_dispatch(crp);
1108 * AH output callback from the crypto driver.
1111 ah_output_cb(struct cryptop *crp)
1113 int skip, protoff, error;
1114 struct tdb_crypto *tc;
1115 struct ipsecrequest *isr;
1116 struct secasvar *sav;
1121 tc = (struct tdb_crypto *) crp->crp_opaque;
1122 KASSERT(tc != NULL, ("ah_output_cb: null opaque data area!"));
1124 protoff = tc->tc_protoff;
1125 ptr = (caddr_t) (tc + 1);
1126 m = (struct mbuf *) crp->crp_buf;
1131 sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi);
1134 DPRINTF(("ah_output_cb: SA expired while in crypto\n"));
1135 error = ENOBUFS; /*XXX*/
1138 KASSERT(isr->sav == sav, ("ah_output_cb: SA changed\n"));
1140 /* Check for crypto errors. */
1141 if (crp->crp_etype) {
1142 if (sav->tdb_cryptoid != 0)
1143 sav->tdb_cryptoid = crp->crp_sid;
1145 if (crp->crp_etype == EAGAIN) {
1148 return crypto_dispatch(crp);
1151 ahstat.ahs_noxform++;
1152 DPRINTF(("ah_output_cb: crypto error %d\n", crp->crp_etype));
1153 error = crp->crp_etype;
1157 /* Shouldn't happen... */
1159 ahstat.ahs_crypto++;
1160 DPRINTF(("ah_output_cb: bogus returned buffer from crypto\n"));
1164 ahstat.ahs_hist[sav->alg_auth]++;
1167 * Copy original headers (with the new protocol number) back
1170 m_copyback(m, 0, skip, ptr);
1172 /* No longer needed. */
1174 crypto_freereq(crp);
1176 /* NB: m is reclaimed by ipsec_process_done. */
1177 err = ipsec_process_done(m, isr);
1188 crypto_freereq(crp);
1192 static struct xformsw ah_xformsw = {
1193 XF_AH, XFT_AUTH, "IPsec AH",
1194 ah_init, ah_zeroize, ah_input, ah_output,
1200 xform_register(&ah_xformsw);
1202 SYSINIT(ah_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ah_attach, NULL);