/* $NetBSD: ah_input.c,v 1.25 2001/02/11 06:49:51 itojun Exp $ */ /* $KAME: ah_input.c,v 1.51 2001/02/08 14:24:05 itojun Exp $ */ /* * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the project nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * RFC1826/2402 authentication header. */ #include "opt_inet.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef INET6 #include #include #include #endif #include #include #include #include #include #include #include #define IPLEN_FLIPPED #ifdef INET void #if __STDC__ ah4_input(struct mbuf *m, ...) #else ah4_input(m, va_alist) struct mbuf *m; va_dcl #endif { struct ip *ip; struct ah *ah; u_int32_t spi; const struct ah_algorithm *algo; size_t siz; size_t siz1; u_char *cksum; struct secasvar *sav = NULL; u_int16_t nxt; size_t hlen; int s; int off, proto; va_list ap; va_start(ap, m); off = va_arg(ap, int); proto = va_arg(ap, int); va_end(ap); #ifndef PULLDOWN_TEST if (m->m_len < off + sizeof(struct newah)) { m = m_pullup(m, off + sizeof(struct newah)); if (!m) { ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup;" "dropping the packet for simplicity\n")); ipsecstat.in_inval++; goto fail; } } ip = mtod(m, struct ip *); ah = (struct ah *)(((caddr_t)ip) + off); #else ip = mtod(m, struct ip *); IP6_EXTHDR_GET(ah, struct ah *, m, off, sizeof(struct newah)); if (ah == NULL) { ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup;" "dropping the packet for simplicity\n")); ipsecstat.in_inval++; goto fail; } #endif nxt = ah->ah_nxt; #ifdef _IP_VHL hlen = IP_VHL_HL(ip->ip_vhl) << 2; #else hlen = ip->ip_hl << 2; #endif /* find the sassoc. */ spi = ah->ah_spi; if ((sav = key_allocsa(AF_INET, (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst, IPPROTO_AH, spi)) == 0) { ipseclog((LOG_WARNING, "IPv4 AH input: no key association found for spi %u\n", (u_int32_t)ntohl(spi))); ipsecstat.in_nosa++; goto fail; } KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP ah4_input called to allocate SA:%p\n", sav)); if (sav->state != SADB_SASTATE_MATURE && sav->state != SADB_SASTATE_DYING) { ipseclog((LOG_DEBUG, "IPv4 AH input: non-mature/dying SA found for spi %u\n", (u_int32_t)ntohl(spi))); ipsecstat.in_badspi++; goto fail; } algo = ah_algorithm_lookup(sav->alg_auth); if (!algo) { ipseclog((LOG_DEBUG, "IPv4 AH input: " "unsupported authentication algorithm for spi %u\n", (u_int32_t)ntohl(spi))); ipsecstat.in_badspi++; goto fail; } siz = (*algo->sumsiz)(sav); siz1 = ((siz + 3) & ~(4 - 1)); /* * sanity checks for header, 1. */ { int sizoff; sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4; /* * Here, we do not do "siz1 == siz". This is because the way * RFC240[34] section 2 is written. They do not require truncation * to 96 bits. * For example, Microsoft IPsec stack attaches 160 bits of * authentication data for both hmac-md5 and hmac-sha1. For hmac-sha1, * 32 bits of padding is attached. * * There are two downsides to this specification. * They have no real harm, however, they leave us fuzzy feeling. * - if we attach more than 96 bits of authentication data onto AH, * we will never notice about possible modification by rogue * intermediate nodes. * Since extra bits in AH checksum is never used, this constitutes * no real issue, however, it is wacky. * - even if the peer attaches big authentication data, we will never * notice the difference, since longer authentication data will just * work. * * We may need some clarification in the spec. */ if (siz1 < siz) { ipseclog((LOG_NOTICE, "sum length too short in IPv4 AH input " "(%lu, should be at least %lu): %s\n", (u_long)siz1, (u_long)siz, ipsec4_logpacketstr(ip, spi))); ipsecstat.in_inval++; goto fail; } if ((ah->ah_len << 2) - sizoff != siz1) { ipseclog((LOG_NOTICE, "sum length mismatch in IPv4 AH input " "(%d should be %lu): %s\n", (ah->ah_len << 2) - sizoff, (u_long)siz1, ipsec4_logpacketstr(ip, spi))); ipsecstat.in_inval++; goto fail; } #ifndef PULLDOWN_TEST if (m->m_len < off + sizeof(struct ah) + sizoff + siz1) { m = m_pullup(m, off + sizeof(struct ah) + sizoff + siz1); if (!m) { ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup\n")); ipsecstat.in_inval++; goto fail; } ip = mtod(m, struct ip *); ah = (struct ah *)(((caddr_t)ip) + off); } #else IP6_EXTHDR_GET(ah, struct ah *, m, off, sizeof(struct ah) + sizoff + siz1); if (ah == NULL) { ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup\n")); ipsecstat.in_inval++; goto fail; } #endif } /* * check for sequence number. */ if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) { if (ipsec_chkreplay(ntohl(((struct newah *)ah)->ah_seq), sav)) ; /*okey*/ else { ipsecstat.in_ahreplay++; ipseclog((LOG_WARNING, "replay packet in IPv4 AH input: %s %s\n", ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); goto fail; } } /* * alright, it seems sane. now we are going to check the * cryptographic checksum. */ cksum = malloc(siz1, M_TEMP, M_NOWAIT); if (!cksum) { ipseclog((LOG_DEBUG, "IPv4 AH input: " "couldn't alloc temporary region for cksum\n")); ipsecstat.in_inval++; goto fail; } { #if 1 /* * some of IP header fields are flipped to the host endian. * convert them back to network endian. VERY stupid. */ ip->ip_len = htons(ip->ip_len); ip->ip_off = htons(ip->ip_off); #endif if (ah4_calccksum(m, (caddr_t)cksum, siz1, algo, sav)) { free(cksum, M_TEMP); ipsecstat.in_inval++; goto fail; } ipsecstat.in_ahhist[sav->alg_auth]++; #if 1 /* * flip them back. */ ip->ip_len = ntohs(ip->ip_len); ip->ip_off = ntohs(ip->ip_off); #endif } { caddr_t sumpos = NULL; if (sav->flags & SADB_X_EXT_OLD) { /* RFC 1826 */ sumpos = (caddr_t)(ah + 1); } else { /* RFC 2402 */ sumpos = (caddr_t)(((struct newah *)ah) + 1); } if (bcmp(sumpos, cksum, siz) != 0) { ipseclog((LOG_WARNING, "checksum mismatch in IPv4 AH input: %s %s\n", ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); free(cksum, M_TEMP); ipsecstat.in_ahauthfail++; goto fail; } } free(cksum, M_TEMP); m->m_flags |= M_AUTHIPHDR; m->m_flags |= M_AUTHIPDGM; #if 0 /* * looks okey, but we need more sanity check. * XXX should elaborate. */ if (ah->ah_nxt == IPPROTO_IPIP || ah->ah_nxt == IPPROTO_IP) { struct ip *nip; size_t sizoff; sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4; if (m->m_len < off + sizeof(struct ah) + sizoff + siz1 + hlen) { m = m_pullup(m, off + sizeof(struct ah) + sizoff + siz1 + hlen); if (!m) { ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup\n")); ipsecstat.in_inval++; goto fail; } } nip = (struct ip *)((u_char *)(ah + 1) + sizoff + siz1); if (nip->ip_src.s_addr != ip->ip_src.s_addr || nip->ip_dst.s_addr != ip->ip_dst.s_addr) { m->m_flags &= ~M_AUTHIPHDR; m->m_flags &= ~M_AUTHIPDGM; } } #ifdef INET6 else if (ah->ah_nxt == IPPROTO_IPV6) { m->m_flags &= ~M_AUTHIPHDR; m->m_flags &= ~M_AUTHIPDGM; } #endif /*INET6*/ #endif /*0*/ if (m->m_flags & M_AUTHIPHDR && m->m_flags & M_AUTHIPDGM) { #if 0 ipseclog((LOG_DEBUG, "IPv4 AH input: authentication succeess\n")); #endif ipsecstat.in_ahauthsucc++; } else { ipseclog((LOG_WARNING, "authentication failed in IPv4 AH input: %s %s\n", ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); ipsecstat.in_ahauthfail++; goto fail; } /* * update sequence number. */ if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) { if (ipsec_updatereplay(ntohl(((struct newah *)ah)->ah_seq), sav)) { ipsecstat.in_ahreplay++; goto fail; } } /* was it transmitted over the IPsec tunnel SA? */ if (ipsec4_tunnel_validate(ip, nxt, sav)) { /* * strip off all the headers that precedes AH. * IP xx AH IP' payload -> IP' payload * * XXX more sanity checks * XXX relationship with gif? */ size_t stripsiz = 0; u_int8_t tos; tos = ip->ip_tos; if (sav->flags & SADB_X_EXT_OLD) { /* RFC 1826 */ stripsiz = sizeof(struct ah) + siz1; } else { /* RFC 2402 */ stripsiz = sizeof(struct newah) + siz1; } m_adj(m, off + stripsiz); if (m->m_len < sizeof(*ip)) { m = m_pullup(m, sizeof(*ip)); if (!m) { ipsecstat.in_inval++; goto fail; } } ip = mtod(m, struct ip *); /* ECN consideration. */ ip_ecn_egress(ip4_ipsec_ecn, &tos, &ip->ip_tos); if (!key_checktunnelsanity(sav, AF_INET, (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst)) { ipseclog((LOG_NOTICE, "ipsec tunnel address mismatch " "in IPv4 AH input: %s %s\n", ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); ipsecstat.in_inval++; goto fail; } #if 0 /* XXX should we call ipfw rather than ipsec_in_reject? */ /* drop it if it does not match the default policy */ if (ipsec4_in_reject(m, NULL)) { ipsecstat.in_polvio++; goto fail; } #endif #if 1 /* * Should the inner packet be considered authentic? * My current answer is: NO. * * host1 -- gw1 === gw2 -- host2 * In this case, gw2 can trust the authenticity of the * outer packet, but NOT inner. Packet may be altered * between host1 and gw1. * * host1 -- gw1 === host2 * This case falls into the same scenario as above. * * host1 === host2 * This case is the only case when we may be able to leave * M_AUTHIPHDR and M_AUTHIPDGM set. * However, if host1 is wrongly configured, and allows * attacker to inject some packet with src=host1 and * dst=host2, you are in risk. */ m->m_flags &= ~M_AUTHIPHDR; m->m_flags &= ~M_AUTHIPDGM; #endif key_sa_recordxfer(sav, m); if (ipsec_addhist(m, IPPROTO_AH, spi) != 0 || ipsec_addhist(m, IPPROTO_IPV4, 0) != 0) { ipsecstat.in_nomem++; goto fail; } s = splimp(); if (IF_QFULL(&ipintrq)) { ipsecstat.in_inval++; splx(s); goto fail; } IF_ENQUEUE(&ipintrq, m); m = NULL; schednetisr(NETISR_IP); /*can be skipped but to make sure*/ splx(s); nxt = IPPROTO_DONE; } else { /* * strip off AH. */ size_t stripsiz = 0; if (sav->flags & SADB_X_EXT_OLD) { /* RFC 1826 */ stripsiz = sizeof(struct ah) + siz1; } else { /* RFC 2402 */ stripsiz = sizeof(struct newah) + siz1; } ip = mtod(m, struct ip *); #ifndef PULLDOWN_TEST /* * We do deep-copy since KAME requires that * the packet is placed in a single external mbuf. */ ovbcopy((caddr_t)ip, (caddr_t)(((u_char *)ip) + stripsiz), off); m->m_data += stripsiz; m->m_len -= stripsiz; m->m_pkthdr.len -= stripsiz; #else /* * even in m_pulldown case, we need to strip off AH so that * we can compute checksum for multiple AH correctly. */ if (m->m_len >= stripsiz + off) { ovbcopy((caddr_t)ip, ((caddr_t)ip) + stripsiz, off); m->m_data += stripsiz; m->m_len -= stripsiz; m->m_pkthdr.len -= stripsiz; } else { /* * this comes with no copy if the boundary is on * cluster */ struct mbuf *n; n = m_split(m, off, M_DONTWAIT); if (n == NULL) { /* m is retained by m_split */ goto fail; } m_adj(n, stripsiz); m_cat(m, n); /* m_cat does not update m_pkthdr.len */ m->m_pkthdr.len += n->m_pkthdr.len; } #endif if (m->m_len < sizeof(*ip)) { m = m_pullup(m, sizeof(*ip)); if (m == NULL) { ipsecstat.in_inval++; goto fail; } } ip = mtod(m, struct ip *); #ifdef IPLEN_FLIPPED ip->ip_len = ip->ip_len - stripsiz; #else ip->ip_len = htons(ntohs(ip->ip_len) - stripsiz); #endif ip->ip_p = nxt; /* forget about IP hdr checksum, the check has already been passed */ key_sa_recordxfer(sav, m); if (ipsec_addhist(m, IPPROTO_AH, spi) != 0) { ipsecstat.in_nomem++; goto fail; } if (nxt != IPPROTO_DONE) (*inetsw[ip_protox[nxt]].pr_input)(m, off, nxt); else m_freem(m); m = NULL; } if (sav) { KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP ah4_input call free SA:%p\n", sav)); key_freesav(sav); } ipsecstat.in_success++; return; fail: if (sav) { KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP ah4_input call free SA:%p\n", sav)); key_freesav(sav); } if (m) m_freem(m); return; } /* assumes that ip header and ah header are contiguous on mbuf */ void * ah4_ctlinput(cmd, sa, v) int cmd; struct sockaddr *sa; void *v; { struct ip *ip = v; struct ah *ah; struct icmp *icp; struct secasvar *sav; if (sa->sa_family != AF_INET || sa->sa_len != sizeof(struct sockaddr_in)) return NULL; if ((unsigned)cmd >= PRC_NCMDS) return NULL; if (cmd == PRC_MSGSIZE && ip_mtudisc && ip && ip->ip_v == 4) { /* * Check to see if we have a valid SA corresponding to * the address in the ICMP message payload. */ ah = (struct ah *)((caddr_t)ip + (ip->ip_hl << 2)); if ((sav = key_allocsa(AF_INET, (caddr_t) &ip->ip_src, (caddr_t) &ip->ip_dst, IPPROTO_AH, ah->ah_spi)) == NULL) return NULL; if (sav->state != SADB_SASTATE_MATURE && sav->state != SADB_SASTATE_DYING) { key_freesav(sav); return NULL; } /* XXX Further validation? */ key_freesav(sav); /* * Now that we've validated that we are actually communicating * with the host indicated in the ICMP message, locate the * ICMP header, recalculate the new MTU, and create the * corresponding routing entry. */ icp = (struct icmp *)((caddr_t)ip - offsetof(struct icmp, icmp_ip)); icmp_mtudisc(icp, ip->ip_dst); return NULL; } return NULL; } #endif /* INET */ #ifdef INET6 int ah6_input(mp, offp, proto) struct mbuf **mp; int *offp, proto; { struct mbuf *m = *mp; int off = *offp; struct ip6_hdr *ip6; struct ah *ah; u_int32_t spi; const struct ah_algorithm *algo; size_t siz; size_t siz1; u_char *cksum; struct secasvar *sav = NULL; u_int16_t nxt; int s; #ifndef PULLDOWN_TEST IP6_EXTHDR_CHECK(m, off, sizeof(struct ah), IPPROTO_DONE); ah = (struct ah *)(mtod(m, caddr_t) + off); #else IP6_EXTHDR_GET(ah, struct ah *, m, off, sizeof(struct newah)); if (ah == NULL) { ipseclog((LOG_DEBUG, "IPv6 AH input: can't pullup\n")); ipsec6stat.in_inval++; return IPPROTO_DONE; } #endif ip6 = mtod(m, struct ip6_hdr *); nxt = ah->ah_nxt; /* find the sassoc. */ spi = ah->ah_spi; if (ntohs(ip6->ip6_plen) == 0) { ipseclog((LOG_ERR, "IPv6 AH input: " "AH with IPv6 jumbogram is not supported.\n")); ipsec6stat.in_inval++; goto fail; } if ((sav = key_allocsa(AF_INET6, (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst, IPPROTO_AH, spi)) == 0) { ipseclog((LOG_WARNING, "IPv6 AH input: no key association found for spi %u\n", (u_int32_t)ntohl(spi))); ipsec6stat.in_nosa++; goto fail; } KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP ah6_input called to allocate SA:%p\n", sav)); if (sav->state != SADB_SASTATE_MATURE && sav->state != SADB_SASTATE_DYING) { ipseclog((LOG_DEBUG, "IPv6 AH input: non-mature/dying SA found for spi %u; ", (u_int32_t)ntohl(spi))); ipsec6stat.in_badspi++; goto fail; } algo = ah_algorithm_lookup(sav->alg_auth); if (!algo) { ipseclog((LOG_DEBUG, "IPv6 AH input: " "unsupported authentication algorithm for spi %u\n", (u_int32_t)ntohl(spi))); ipsec6stat.in_badspi++; goto fail; } siz = (*algo->sumsiz)(sav); siz1 = ((siz + 3) & ~(4 - 1)); /* * sanity checks for header, 1. */ { int sizoff; sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4; /* * Here, we do not do "siz1 == siz". See ah4_input() for complete * description. */ if (siz1 < siz) { ipseclog((LOG_NOTICE, "sum length too short in IPv6 AH input " "(%lu, should be at least %lu): %s\n", (u_long)siz1, (u_long)siz, ipsec6_logpacketstr(ip6, spi))); ipsec6stat.in_inval++; goto fail; } if ((ah->ah_len << 2) - sizoff != siz1) { ipseclog((LOG_NOTICE, "sum length mismatch in IPv6 AH input " "(%d should be %lu): %s\n", (ah->ah_len << 2) - sizoff, (u_long)siz1, ipsec6_logpacketstr(ip6, spi))); ipsec6stat.in_inval++; goto fail; } #ifndef PULLDOWN_TEST IP6_EXTHDR_CHECK(m, off, sizeof(struct ah) + sizoff + siz1, IPPROTO_DONE); #else IP6_EXTHDR_GET(ah, struct ah *, m, off, sizeof(struct ah) + sizoff + siz1); if (ah == NULL) { ipseclog((LOG_NOTICE, "couldn't pullup gather IPv6 AH checksum part")); ipsec6stat.in_inval++; m = NULL; goto fail; } #endif } /* * check for sequence number. */ if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) { if (ipsec_chkreplay(ntohl(((struct newah *)ah)->ah_seq), sav)) ; /*okey*/ else { ipsec6stat.in_ahreplay++; ipseclog((LOG_WARNING, "replay packet in IPv6 AH input: %s %s\n", ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); goto fail; } } /* * alright, it seems sane. now we are going to check the * cryptographic checksum. */ cksum = malloc(siz1, M_TEMP, M_NOWAIT); if (!cksum) { ipseclog((LOG_DEBUG, "IPv6 AH input: " "couldn't alloc temporary region for cksum\n")); ipsec6stat.in_inval++; goto fail; } if (ah6_calccksum(m, (caddr_t)cksum, siz1, algo, sav)) { free(cksum, M_TEMP); ipsec6stat.in_inval++; goto fail; } ipsec6stat.in_ahhist[sav->alg_auth]++; { caddr_t sumpos = NULL; if (sav->flags & SADB_X_EXT_OLD) { /* RFC 1826 */ sumpos = (caddr_t)(ah + 1); } else { /* RFC 2402 */ sumpos = (caddr_t)(((struct newah *)ah) + 1); } if (bcmp(sumpos, cksum, siz) != 0) { ipseclog((LOG_WARNING, "checksum mismatch in IPv6 AH input: %s %s\n", ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); free(cksum, M_TEMP); ipsec6stat.in_ahauthfail++; goto fail; } } free(cksum, M_TEMP); m->m_flags |= M_AUTHIPHDR; m->m_flags |= M_AUTHIPDGM; #if 0 /* * looks okey, but we need more sanity check. * XXX should elaborate. */ if (ah->ah_nxt == IPPROTO_IPV6) { struct ip6_hdr *nip6; size_t sizoff; sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4; IP6_EXTHDR_CHECK(m, off, sizeof(struct ah) + sizoff + siz1 + sizeof(struct ip6_hdr), IPPROTO_DONE); nip6 = (struct ip6_hdr *)((u_char *)(ah + 1) + sizoff + siz1); if (!IN6_ARE_ADDR_EQUAL(&nip6->ip6_src, &ip6->ip6_src) || !IN6_ARE_ADDR_EQUAL(&nip6->ip6_dst, &ip6->ip6_dst)) { m->m_flags &= ~M_AUTHIPHDR; m->m_flags &= ~M_AUTHIPDGM; } } else if (ah->ah_nxt == IPPROTO_IPIP) { m->m_flags &= ~M_AUTHIPHDR; m->m_flags &= ~M_AUTHIPDGM; } else if (ah->ah_nxt == IPPROTO_IP) { m->m_flags &= ~M_AUTHIPHDR; m->m_flags &= ~M_AUTHIPDGM; } #endif if (m->m_flags & M_AUTHIPHDR && m->m_flags & M_AUTHIPDGM) { #if 0 ipseclog((LOG_DEBUG, "IPv6 AH input: authentication succeess\n")); #endif ipsec6stat.in_ahauthsucc++; } else { ipseclog((LOG_WARNING, "authentication failed in IPv6 AH input: %s %s\n", ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); ipsec6stat.in_ahauthfail++; goto fail; } /* * update sequence number. */ if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) { if (ipsec_updatereplay(ntohl(((struct newah *)ah)->ah_seq), sav)) { ipsec6stat.in_ahreplay++; goto fail; } } /* was it transmitted over the IPsec tunnel SA? */ if (ipsec6_tunnel_validate(ip6, nxt, sav)) { /* * strip off all the headers that precedes AH. * IP6 xx AH IP6' payload -> IP6' payload * * XXX more sanity checks * XXX relationship with gif? */ size_t stripsiz = 0; u_int32_t flowinfo; /*net endian*/ flowinfo = ip6->ip6_flow; if (sav->flags & SADB_X_EXT_OLD) { /* RFC 1826 */ stripsiz = sizeof(struct ah) + siz1; } else { /* RFC 2402 */ stripsiz = sizeof(struct newah) + siz1; } m_adj(m, off + stripsiz); if (m->m_len < sizeof(*ip6)) { /* * m_pullup is prohibited in KAME IPv6 input processing * but there's no other way! */ m = m_pullup(m, sizeof(*ip6)); if (!m) { ipsec6stat.in_inval++; goto fail; } } ip6 = mtod(m, struct ip6_hdr *); /* ECN consideration. */ ip6_ecn_egress(ip6_ipsec_ecn, &flowinfo, &ip6->ip6_flow); if (!key_checktunnelsanity(sav, AF_INET6, (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst)) { ipseclog((LOG_NOTICE, "ipsec tunnel address mismatch " "in IPv6 AH input: %s %s\n", ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); ipsec6stat.in_inval++; goto fail; } #if 0 /* XXX should we call ipfw rather than ipsec_in_reject? */ /* drop it if it does not match the default policy */ if (ipsec6_in_reject(m, NULL)) { ipsec6stat.in_polvio++; goto fail; } #endif #if 1 /* * should the inner packet be considered authentic? * see comment in ah4_input(). */ m->m_flags &= ~M_AUTHIPHDR; m->m_flags &= ~M_AUTHIPDGM; #endif key_sa_recordxfer(sav, m); if (ipsec_addhist(m, IPPROTO_AH, spi) != 0 || ipsec_addhist(m, IPPROTO_IPV6, 0) != 0) { ipsec6stat.in_nomem++; goto fail; } s = splimp(); if (IF_QFULL(&ip6intrq)) { ipsec6stat.in_inval++; splx(s); goto fail; } IF_ENQUEUE(&ip6intrq, m); m = NULL; schednetisr(NETISR_IPV6); /*can be skipped but to make sure*/ splx(s); nxt = IPPROTO_DONE; } else { /* * strip off AH. */ size_t stripsiz = 0; char *prvnxtp; /* * Copy the value of the next header field of AH to the * next header field of the previous header. * This is necessary because AH will be stripped off below. */ prvnxtp = ip6_get_prevhdr(m, off); /* XXX */ *prvnxtp = nxt; if (sav->flags & SADB_X_EXT_OLD) { /* RFC 1826 */ stripsiz = sizeof(struct ah) + siz1; } else { /* RFC 2402 */ stripsiz = sizeof(struct newah) + siz1; } ip6 = mtod(m, struct ip6_hdr *); #ifndef PULLDOWN_TEST /* * We do deep-copy since KAME requires that * the packet is placed in a single mbuf. */ ovbcopy((caddr_t)ip6, ((caddr_t)ip6) + stripsiz, off); m->m_data += stripsiz; m->m_len -= stripsiz; m->m_pkthdr.len -= stripsiz; #else /* * even in m_pulldown case, we need to strip off AH so that * we can compute checksum for multiple AH correctly. */ if (m->m_len >= stripsiz + off) { ovbcopy((caddr_t)ip6, ((caddr_t)ip6) + stripsiz, off); m->m_data += stripsiz; m->m_len -= stripsiz; m->m_pkthdr.len -= stripsiz; } else { /* * this comes with no copy if the boundary is on * cluster */ struct mbuf *n; n = m_split(m, off, M_DONTWAIT); if (n == NULL) { /* m is retained by m_split */ goto fail; } m_adj(n, stripsiz); m_cat(m, n); /* m_cat does not update m_pkthdr.len */ m->m_pkthdr.len += n->m_pkthdr.len; } #endif ip6 = mtod(m, struct ip6_hdr *); /* XXX jumbogram */ ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - stripsiz); key_sa_recordxfer(sav, m); if (ipsec_addhist(m, IPPROTO_AH, spi) != 0) { ipsec6stat.in_nomem++; goto fail; } } *offp = off; *mp = m; if (sav) { KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP ah6_input call free SA:%p\n", sav)); key_freesav(sav); } ipsec6stat.in_success++; return nxt; fail: if (sav) { KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP ah6_input call free SA:%p\n", sav)); key_freesav(sav); } if (m) m_freem(m); return IPPROTO_DONE; } void ah6_ctlinput(cmd, sa, d) int cmd; struct sockaddr *sa; void *d; { const struct newah *ahp; struct newah ah; struct secasvar *sav; struct ip6_hdr *ip6; struct mbuf *m; struct ip6ctlparam *ip6cp = NULL; int off; struct sockaddr_in6 sa6_src, sa6_dst; if (sa->sa_family != AF_INET6 || sa->sa_len != sizeof(struct sockaddr_in6)) return; if ((unsigned)cmd >= PRC_NCMDS) return; /* if the parameter is from icmp6, decode it. */ if (d != NULL) { ip6cp = (struct ip6ctlparam *)d; m = ip6cp->ip6c_m; ip6 = ip6cp->ip6c_ip6; off = ip6cp->ip6c_off; } else { m = NULL; ip6 = NULL; } if (ip6) { /* * XXX: We assume that when ip6 is non NULL, * M and OFF are valid. */ /* check if we can safely examine src and dst ports */ if (m->m_pkthdr.len < off + sizeof(ah)) return; if (m->m_len < off + sizeof(ah)) { /* * this should be rare case, * so we compromise on this copy... */ m_copydata(m, off, sizeof(ah), (caddr_t)&ah); ahp = &ah; } else ahp = (struct newah *)(mtod(m, caddr_t) + off); if (cmd == PRC_MSGSIZE) { int valid = 0; /* * Check to see if we have a valid SA corresponding to * the address in the ICMP message payload. */ sav = key_allocsa(AF_INET6, (caddr_t)&sa6_src.sin6_addr, (caddr_t)&sa6_dst.sin6_addr, IPPROTO_AH, ahp->ah_spi); if (sav) { if (sav->state == SADB_SASTATE_MATURE || sav->state == SADB_SASTATE_DYING) valid++; key_freesav(sav); } /* XXX Further validation? */ /* * Depending on the value of "valid" and routing table * size (mtudisc_{hi,lo}wat), we will: * - recalcurate the new MTU and create the * corresponding routing entry, or * - ignore the MTU change notification. */ icmp6_mtudisc_update((struct ip6ctlparam *)d, valid); } /* we normally notify single pcb here */ } else { /* we normally notify any pcb here */ } } #endif /* INET6 */