/* * Copyright (c) 2008-2013 Apple Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ /* $FreeBSD: src/sys/netinet6/esp_input.c,v 1.1.2.3 2001/07/03 11:01:50 ume Exp $ */ /* $KAME: esp_input.c,v 1.55 2001/03/23 08:08:47 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. */ /* * RFC1827/2406 Encapsulated Security Payload. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if INET6 #include #endif #if INET6 #include #include #include #include #include #endif #include #if INET6 #include #endif #include #if INET6 #include #endif #include #if INET6 #include #endif #include #include #include #include #include #include #include #include #define DBG_LAYER_BEG NETDBG_CODE(DBG_NETIPSEC, 1) #define DBG_LAYER_END NETDBG_CODE(DBG_NETIPSEC, 3) #define DBG_FNC_ESPIN NETDBG_CODE(DBG_NETIPSEC, (6 << 8)) #define DBG_FNC_DECRYPT NETDBG_CODE(DBG_NETIPSEC, (7 << 8)) #define IPLEN_FLIPPED extern lck_mtx_t *sadb_mutex; #if INET #define ESPMAXLEN \ (sizeof(struct esp) < sizeof(struct newesp) \ ? sizeof(struct newesp) : sizeof(struct esp)) static struct ip * esp4_input_strip_UDP_encap (struct mbuf *m, int iphlen) { // strip the udp header that's encapsulating ESP struct ip *ip; size_t stripsiz = sizeof(struct udphdr); ip = mtod(m, __typeof__(ip)); ovbcopy((caddr_t)ip, (caddr_t)(((u_char *)ip) + stripsiz), iphlen); m->m_data += stripsiz; m->m_len -= stripsiz; m->m_pkthdr.len -= stripsiz; ip = mtod(m, __typeof__(ip)); ip->ip_len = ip->ip_len - stripsiz; ip->ip_p = IPPROTO_ESP; return ip; } void esp4_input(m, off) struct mbuf *m; int off; { struct ip *ip; #if INET6 struct ip6_hdr *ip6; #endif /* INET6 */ struct esp *esp; struct esptail esptail; u_int32_t spi; u_int32_t seq; struct secasvar *sav = NULL; size_t taillen; u_int16_t nxt; const struct esp_algorithm *algo; int ivlen; size_t hlen; size_t esplen; sa_family_t ifamily; KERNEL_DEBUG(DBG_FNC_ESPIN | DBG_FUNC_START, 0,0,0,0,0); /* sanity check for alignment. */ if (off % 4 != 0 || m->m_pkthdr.len % 4 != 0) { ipseclog((LOG_ERR, "IPv4 ESP input: packet alignment problem " "(off=%d, pktlen=%d)\n", off, m->m_pkthdr.len)); IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } if (m->m_len < off + ESPMAXLEN) { m = m_pullup(m, off + ESPMAXLEN); if (!m) { ipseclog((LOG_DEBUG, "IPv4 ESP input: can't pullup in esp4_input\n")); IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } } /* Expect 32-bit aligned data pointer on strict-align platforms */ MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m); ip = mtod(m, struct ip *); // expect udp-encap and esp packets only if (ip->ip_p != IPPROTO_ESP && !(ip->ip_p == IPPROTO_UDP && off >= sizeof(struct udphdr))) { ipseclog((LOG_DEBUG, "IPv4 ESP input: invalid protocol type\n")); IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } esp = (struct esp *)(void *)(((u_int8_t *)ip) + off); #ifdef _IP_VHL hlen = IP_VHL_HL(ip->ip_vhl) << 2; #else hlen = ip->ip_hl << 2; #endif /* find the sassoc. */ spi = esp->esp_spi; if ((sav = key_allocsa(AF_INET, (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst, IPPROTO_ESP, spi)) == 0) { ipseclog((LOG_WARNING, "IPv4 ESP input: no key association found for spi %u\n", (u_int32_t)ntohl(spi))); IPSEC_STAT_INCREMENT(ipsecstat.in_nosa); goto bad; } KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP esp4_input called to allocate SA:0x%llx\n", (uint64_t)VM_KERNEL_ADDRPERM(sav))); if (sav->state != SADB_SASTATE_MATURE && sav->state != SADB_SASTATE_DYING) { ipseclog((LOG_DEBUG, "IPv4 ESP input: non-mature/dying SA found for spi %u\n", (u_int32_t)ntohl(spi))); IPSEC_STAT_INCREMENT(ipsecstat.in_badspi); goto bad; } algo = esp_algorithm_lookup(sav->alg_enc); if (!algo) { ipseclog((LOG_DEBUG, "IPv4 ESP input: " "unsupported encryption algorithm for spi %u\n", (u_int32_t)ntohl(spi))); IPSEC_STAT_INCREMENT(ipsecstat.in_badspi); goto bad; } /* check if we have proper ivlen information */ ivlen = sav->ivlen; if (ivlen < 0) { ipseclog((LOG_ERR, "inproper ivlen in IPv4 ESP input: %s %s\n", ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } seq = ntohl(((struct newesp *)esp)->esp_seq); if (!((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay && (sav->alg_auth && sav->key_auth))) goto noreplaycheck; if (sav->alg_auth == SADB_X_AALG_NULL || sav->alg_auth == SADB_AALG_NONE) goto noreplaycheck; /* * check for sequence number. */ if (ipsec_chkreplay(seq, sav)) ; /*okey*/ else { IPSEC_STAT_INCREMENT(ipsecstat.in_espreplay); ipseclog((LOG_WARNING, "replay packet in IPv4 ESP input: %s %s\n", ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); goto bad; } /* check ICV */ { u_char sum0[AH_MAXSUMSIZE] __attribute__((aligned(4))); u_char sum[AH_MAXSUMSIZE] __attribute__((aligned(4))); const struct ah_algorithm *sumalgo; size_t siz; sumalgo = ah_algorithm_lookup(sav->alg_auth); if (!sumalgo) goto noreplaycheck; siz = (((*sumalgo->sumsiz)(sav) + 3) & ~(4 - 1)); if (m->m_pkthdr.len < off + ESPMAXLEN + siz) { IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } if (AH_MAXSUMSIZE < siz) { ipseclog((LOG_DEBUG, "internal error: AH_MAXSUMSIZE must be larger than %lu\n", (u_int32_t)siz)); IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } m_copydata(m, m->m_pkthdr.len - siz, siz, (caddr_t) &sum0[0]); if (esp_auth(m, off, m->m_pkthdr.len - off - siz, sav, sum)) { ipseclog((LOG_WARNING, "auth fail in IPv4 ESP input: %s %s\n", ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); IPSEC_STAT_INCREMENT(ipsecstat.in_espauthfail); goto bad; } if (bcmp(sum0, sum, siz) != 0) { ipseclog((LOG_WARNING, "auth fail in IPv4 ESP input: %s %s\n", ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); IPSEC_STAT_INCREMENT(ipsecstat.in_espauthfail); goto bad; } /* strip off the authentication data */ m_adj(m, -siz); ip = mtod(m, struct ip *); #ifdef IPLEN_FLIPPED ip->ip_len = ip->ip_len - siz; #else ip->ip_len = htons(ntohs(ip->ip_len) - siz); #endif m->m_flags |= M_AUTHIPDGM; IPSEC_STAT_INCREMENT(ipsecstat.in_espauthsucc); } /* * update sequence number. */ if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) { if (ipsec_updatereplay(seq, sav)) { IPSEC_STAT_INCREMENT(ipsecstat.in_espreplay); goto bad; } } noreplaycheck: /* process main esp header. */ if (sav->flags & SADB_X_EXT_OLD) { /* RFC 1827 */ esplen = sizeof(struct esp); } else { /* RFC 2406 */ if (sav->flags & SADB_X_EXT_DERIV) esplen = sizeof(struct esp); else esplen = sizeof(struct newesp); } if (m->m_pkthdr.len < off + esplen + ivlen + sizeof(esptail)) { ipseclog((LOG_WARNING, "IPv4 ESP input: packet too short\n")); IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } if (m->m_len < off + esplen + ivlen) { m = m_pullup(m, off + esplen + ivlen); if (!m) { ipseclog((LOG_DEBUG, "IPv4 ESP input: can't pullup in esp4_input\n")); IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } } /* * pre-compute and cache intermediate key */ if (esp_schedule(algo, sav) != 0) { IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } /* * decrypt the packet. */ if (!algo->decrypt) panic("internal error: no decrypt function"); KERNEL_DEBUG(DBG_FNC_DECRYPT | DBG_FUNC_START, 0,0,0,0,0); if ((*algo->decrypt)(m, off, sav, algo, ivlen)) { /* m is already freed */ m = NULL; ipseclog((LOG_ERR, "decrypt fail in IPv4 ESP input: %s\n", ipsec_logsastr(sav))); IPSEC_STAT_INCREMENT(ipsecstat.in_inval); KERNEL_DEBUG(DBG_FNC_DECRYPT | DBG_FUNC_END, 1,0,0,0,0); goto bad; } KERNEL_DEBUG(DBG_FNC_DECRYPT | DBG_FUNC_END, 2,0,0,0,0); IPSEC_STAT_INCREMENT(ipsecstat.in_esphist[sav->alg_enc]); m->m_flags |= M_DECRYPTED; /* * find the trailer of the ESP. */ m_copydata(m, m->m_pkthdr.len - sizeof(esptail), sizeof(esptail), (caddr_t)&esptail); nxt = esptail.esp_nxt; taillen = esptail.esp_padlen + sizeof(esptail); if (m->m_pkthdr.len < taillen || m->m_pkthdr.len - taillen < hlen) { /*?*/ ipseclog((LOG_WARNING, "bad pad length in IPv4 ESP input: %s %s\n", ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } /* strip off the trailing pad area. */ m_adj(m, -taillen); ip = mtod(m, struct ip *); #ifdef IPLEN_FLIPPED ip->ip_len = ip->ip_len - taillen; #else ip->ip_len = htons(ntohs(ip->ip_len) - taillen); #endif if (ip->ip_p == IPPROTO_UDP) { // offset includes the outer ip and udp header lengths. if (m->m_len < off) { m = m_pullup(m, off); if (!m) { ipseclog((LOG_DEBUG, "IPv4 ESP input: invalid udp encapsulated ESP packet length \n")); IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } } // check the UDP encap header to detect changes in the source port, and then strip the header off -= sizeof(struct udphdr); // off no longer includes the udphdr's size // if peer is behind nat and this is the latest esp packet if ((sav->flags & SADB_X_EXT_NATT_DETECTED_PEER) != 0 && (sav->flags & SADB_X_EXT_OLD) == 0 && seq && sav->replay && seq >= sav->replay->lastseq) { struct udphdr *encap_uh = (__typeof__(encap_uh))(void *)((caddr_t)ip + off); if (encap_uh->uh_sport && ntohs(encap_uh->uh_sport) != sav->remote_ike_port) { sav->remote_ike_port = ntohs(encap_uh->uh_sport); } } ip = esp4_input_strip_UDP_encap(m, off); esp = (struct esp *)(void *)(((u_int8_t *)ip) + off); } if (sav->utun_is_keepalive_fn) { if (sav->utun_is_keepalive_fn(sav->utun_pcb, &m, nxt, sav->flags, (off + esplen + ivlen))) { if (m) { // not really bad, we just wanna exit IPSEC_STAT_INCREMENT(ipsecstat.in_success); m = NULL; } goto bad; } } /* was it transmitted over the IPsec tunnel SA? */ if (ipsec4_tunnel_validate(m, off + esplen + ivlen, nxt, sav, &ifamily)) { ifaddr_t ifa; struct sockaddr_storage addr; /* * strip off all the headers that precedes ESP header. * IP4 xx ESP IP4' payload -> IP4' payload * * XXX more sanity checks * XXX relationship with gif? */ u_int8_t tos; tos = ip->ip_tos; m_adj(m, off + esplen + ivlen); if (ifamily == AF_INET) { struct sockaddr_in *ipaddr; if (m->m_len < sizeof(*ip)) { m = m_pullup(m, sizeof(*ip)); if (!m) { IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } } 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_ERR, "ipsec tunnel address mismatch " "in ESP input: %s %s\n", ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } if (ip_doscopedroute) { bzero(&addr, sizeof(addr)); ipaddr = (__typeof__(ipaddr))&addr; ipaddr->sin_family = AF_INET; ipaddr->sin_len = sizeof(*ipaddr); ipaddr->sin_addr = ip->ip_dst; } #if INET6 } else if (ifamily == AF_INET6) { struct sockaddr_in6 *ip6addr; /* * m_pullup is prohibited in KAME IPv6 input processing * but there's no other way! */ if (m->m_len < sizeof(*ip6)) { m = m_pullup(m, sizeof(*ip6)); if (!m) { IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } } /* * Expect 32-bit aligned data pointer on strict-align * platforms. */ MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m); ip6 = mtod(m, struct ip6_hdr *); /* ECN consideration. */ /* XXX To be fixed later if needed */ // ip_ecn_egress(ip4_ipsec_ecn, &tos, &ip->ip_tos); if (!key_checktunnelsanity(sav, AF_INET6, (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst)) { ipseclog((LOG_ERR, "ipsec tunnel address mismatch " "in ESP input: %s %s\n", ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } if (ip6_doscopedroute) { bzero(&addr, sizeof(addr)); ip6addr = (__typeof__(ip6addr))&addr; ip6addr->sin6_family = AF_INET6; ip6addr->sin6_len = sizeof(*ip6addr); ip6addr->sin6_addr = ip6->ip6_dst; } #endif /* INET6 */ } else { ipseclog((LOG_ERR, "ipsec tunnel unsupported address family " "in ESP input\n")); goto bad; } key_sa_recordxfer(sav, m); if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0 || ipsec_addhist(m, IPPROTO_IPV4, 0) != 0) { IPSEC_STAT_INCREMENT(ipsecstat.in_nomem); goto bad; } if (ip_doscopedroute || ip6_doscopedroute) { // update the receiving interface address based on the inner address ifa = ifa_ifwithaddr((struct sockaddr *)&addr); if (ifa) { m->m_pkthdr.rcvif = ifa->ifa_ifp; IFA_REMREF(ifa); } } /* Clear the csum flags, they can't be valid for the inner headers */ m->m_pkthdr.csum_flags = 0; // Input via IPSec interface if (sav->sah->ipsec_if != NULL) { if (ipsec_inject_inbound_packet(sav->sah->ipsec_if, m) == 0) { m = NULL; goto done; } else { goto bad; } } if (sav->utun_in_fn) { if (!(sav->utun_in_fn(sav->utun_pcb, &m, ifamily == AF_INET ? PF_INET : PF_INET6))) { m = NULL; // we just wanna exit since packet has been completely processed goto bad; } } if (proto_input(ifamily == AF_INET ? PF_INET : PF_INET6, m) != 0) goto bad; nxt = IPPROTO_DONE; KERNEL_DEBUG(DBG_FNC_ESPIN | DBG_FUNC_END, 2,0,0,0,0); } else { /* * strip off ESP header and IV. * even in m_pulldown case, we need to strip off ESP so that * we can always compute checksum for AH correctly. */ size_t stripsiz; stripsiz = esplen + ivlen; ip = mtod(m, struct ip *); ovbcopy((caddr_t)ip, (caddr_t)(((u_char *)ip) + stripsiz), off); m->m_data += stripsiz; m->m_len -= stripsiz; m->m_pkthdr.len -= stripsiz; 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; key_sa_recordxfer(sav, m); if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0) { IPSEC_STAT_INCREMENT(ipsecstat.in_nomem); goto bad; } /* * Set the csum valid flag, if we authenticated the * packet, the payload shouldn't be corrupt unless * it was corrupted before being signed on the other * side. */ if (nxt == IPPROTO_TCP || nxt == IPPROTO_UDP) { m->m_pkthdr.csum_flags = CSUM_DATA_VALID | CSUM_PSEUDO_HDR; m->m_pkthdr.csum_data = 0xFFFF; } if (nxt != IPPROTO_DONE) { if ((ip_protox[nxt]->pr_flags & PR_LASTHDR) != 0 && ipsec4_in_reject(m, NULL)) { IPSEC_STAT_INCREMENT(ipsecstat.in_polvio); goto bad; } KERNEL_DEBUG(DBG_FNC_ESPIN | DBG_FUNC_END, 3,0,0,0,0); /* translate encapsulated UDP port ? */ if ((sav->flags & SADB_X_EXT_NATT_MULTIPLEUSERS) != 0) { struct udphdr *udp; if (nxt != IPPROTO_UDP) { /* not UPD packet - drop it */ IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } if (m->m_len < off + sizeof(struct udphdr)) { m = m_pullup(m, off + sizeof(struct udphdr)); if (!m) { ipseclog((LOG_DEBUG, "IPv4 ESP input: can't pullup UDP header in esp4_input\n")); IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } ip = mtod(m, struct ip *); } udp = (struct udphdr *)(void *)(((u_int8_t *)ip) + off); lck_mtx_lock(sadb_mutex); if (sav->natt_encapsulated_src_port == 0) { sav->natt_encapsulated_src_port = udp->uh_sport; } else if (sav->natt_encapsulated_src_port != udp->uh_sport) { /* something wrong */ IPSEC_STAT_INCREMENT(ipsecstat.in_inval); lck_mtx_unlock(sadb_mutex); goto bad; } lck_mtx_unlock(sadb_mutex); udp->uh_sport = htons(sav->remote_ike_port); udp->uh_sum = 0; } DTRACE_IP6(receive, struct mbuf *, m, struct inpcb *, NULL, struct ip *, ip, struct ifnet *, m->m_pkthdr.rcvif, struct ip *, ip, struct ip6_hdr *, NULL); // Input via IPSec interface if (sav->sah->ipsec_if != NULL) { ip->ip_len = htons(ip->ip_len + hlen); ip->ip_off = htons(ip->ip_off); ip->ip_sum = 0; ip->ip_sum = ip_cksum_hdr_in(m, hlen); if (ipsec_inject_inbound_packet(sav->sah->ipsec_if, m) == 0) { m = NULL; goto done; } else { goto bad; } } if (sav->utun_in_fn) { if (!(sav->utun_in_fn(sav->utun_pcb, &m, PF_INET))) { m = NULL; // we just wanna exit since packet has been completely processed goto bad; } } ip_proto_dispatch_in(m, off, nxt, 0); } else m_freem(m); m = NULL; } done: if (sav) { KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP esp4_input call free SA:0x%llx\n", (uint64_t)VM_KERNEL_ADDRPERM(sav))); key_freesav(sav, KEY_SADB_UNLOCKED); } IPSEC_STAT_INCREMENT(ipsecstat.in_success); return; bad: if (sav) { KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP esp4_input call free SA:0x%llx\n", (uint64_t)VM_KERNEL_ADDRPERM(sav))); key_freesav(sav, KEY_SADB_UNLOCKED); } if (m) m_freem(m); KERNEL_DEBUG(DBG_FNC_ESPIN | DBG_FUNC_END, 4,0,0,0,0); return; } #endif /* INET */ #if INET6 int esp6_input(struct mbuf **mp, int *offp, int proto) { #pragma unused(proto) struct mbuf *m = *mp; int off = *offp; struct ip6_hdr *ip6; struct esp *esp; struct esptail esptail; u_int32_t spi; u_int32_t seq; struct secasvar *sav = NULL; size_t taillen; u_int16_t nxt; const struct esp_algorithm *algo; int ivlen; size_t esplen; /* sanity check for alignment. */ if (off % 4 != 0 || m->m_pkthdr.len % 4 != 0) { ipseclog((LOG_ERR, "IPv6 ESP input: packet alignment problem " "(off=%d, pktlen=%d)\n", off, m->m_pkthdr.len)); IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); goto bad; } #ifndef PULLDOWN_TEST IP6_EXTHDR_CHECK(m, off, ESPMAXLEN, {return IPPROTO_DONE;}); esp = (struct esp *)(void *)(mtod(m, caddr_t) + off); #else IP6_EXTHDR_GET(esp, struct esp *, m, off, ESPMAXLEN); if (esp == NULL) { IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); return IPPROTO_DONE; } #endif /* Expect 32-bit data aligned pointer on strict-align platforms */ MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m); ip6 = mtod(m, struct ip6_hdr *); if (ntohs(ip6->ip6_plen) == 0) { ipseclog((LOG_ERR, "IPv6 ESP input: " "ESP with IPv6 jumbogram is not supported.\n")); IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); goto bad; } /* find the sassoc. */ spi = esp->esp_spi; if ((sav = key_allocsa(AF_INET6, (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst, IPPROTO_ESP, spi)) == 0) { ipseclog((LOG_WARNING, "IPv6 ESP input: no key association found for spi %u\n", (u_int32_t)ntohl(spi))); IPSEC_STAT_INCREMENT(ipsec6stat.in_nosa); goto bad; } KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP esp6_input called to allocate SA:0x%llx\n", (uint64_t)VM_KERNEL_ADDRPERM(sav))); if (sav->state != SADB_SASTATE_MATURE && sav->state != SADB_SASTATE_DYING) { ipseclog((LOG_DEBUG, "IPv6 ESP input: non-mature/dying SA found for spi %u\n", (u_int32_t)ntohl(spi))); IPSEC_STAT_INCREMENT(ipsec6stat.in_badspi); goto bad; } algo = esp_algorithm_lookup(sav->alg_enc); if (!algo) { ipseclog((LOG_DEBUG, "IPv6 ESP input: " "unsupported encryption algorithm for spi %u\n", (u_int32_t)ntohl(spi))); IPSEC_STAT_INCREMENT(ipsec6stat.in_badspi); goto bad; } /* check if we have proper ivlen information */ ivlen = sav->ivlen; if (ivlen < 0) { ipseclog((LOG_ERR, "inproper ivlen in IPv6 ESP input: %s %s\n", ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); IPSEC_STAT_INCREMENT(ipsec6stat.in_badspi); goto bad; } seq = ntohl(((struct newesp *)esp)->esp_seq); if (!((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay && (sav->alg_auth && sav->key_auth))) goto noreplaycheck; if (sav->alg_auth == SADB_X_AALG_NULL || sav->alg_auth == SADB_AALG_NONE) goto noreplaycheck; /* * check for sequence number. */ if (ipsec_chkreplay(seq, sav)) ; /*okey*/ else { IPSEC_STAT_INCREMENT(ipsec6stat.in_espreplay); ipseclog((LOG_WARNING, "replay packet in IPv6 ESP input: %s %s\n", ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); goto bad; } /* check ICV */ { u_char sum0[AH_MAXSUMSIZE] __attribute__((aligned(4))); u_char sum[AH_MAXSUMSIZE] __attribute__((aligned(4))); const struct ah_algorithm *sumalgo; size_t siz; sumalgo = ah_algorithm_lookup(sav->alg_auth); if (!sumalgo) goto noreplaycheck; siz = (((*sumalgo->sumsiz)(sav) + 3) & ~(4 - 1)); if (m->m_pkthdr.len < off + ESPMAXLEN + siz) { IPSEC_STAT_INCREMENT(ipsecstat.in_inval); goto bad; } if (AH_MAXSUMSIZE < siz) { ipseclog((LOG_DEBUG, "internal error: AH_MAXSUMSIZE must be larger than %lu\n", (u_int32_t)siz)); IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); goto bad; } m_copydata(m, m->m_pkthdr.len - siz, siz, (caddr_t) &sum0[0]); if (esp_auth(m, off, m->m_pkthdr.len - off - siz, sav, sum)) { ipseclog((LOG_WARNING, "auth fail in IPv6 ESP input: %s %s\n", ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); IPSEC_STAT_INCREMENT(ipsec6stat.in_espauthfail); goto bad; } if (bcmp(sum0, sum, siz) != 0) { ipseclog((LOG_WARNING, "auth fail in IPv6 ESP input: %s %s\n", ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); IPSEC_STAT_INCREMENT(ipsec6stat.in_espauthfail); goto bad; } /* strip off the authentication data */ m_adj(m, -siz); ip6 = mtod(m, struct ip6_hdr *); ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - siz); m->m_flags |= M_AUTHIPDGM; IPSEC_STAT_INCREMENT(ipsec6stat.in_espauthsucc); } /* * update sequence number. */ if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) { if (ipsec_updatereplay(seq, sav)) { IPSEC_STAT_INCREMENT(ipsec6stat.in_espreplay); goto bad; } } noreplaycheck: /* process main esp header. */ if (sav->flags & SADB_X_EXT_OLD) { /* RFC 1827 */ esplen = sizeof(struct esp); } else { /* RFC 2406 */ if (sav->flags & SADB_X_EXT_DERIV) esplen = sizeof(struct esp); else esplen = sizeof(struct newesp); } if (m->m_pkthdr.len < off + esplen + ivlen + sizeof(esptail)) { ipseclog((LOG_WARNING, "IPv6 ESP input: packet too short\n")); IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); goto bad; } #ifndef PULLDOWN_TEST IP6_EXTHDR_CHECK(m, off, esplen + ivlen, return IPPROTO_DONE); /*XXX*/ #else IP6_EXTHDR_GET(esp, struct esp *, m, off, esplen + ivlen); if (esp == NULL) { IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); m = NULL; goto bad; } #endif ip6 = mtod(m, struct ip6_hdr *); /*set it again just in case*/ /* * pre-compute and cache intermediate key */ if (esp_schedule(algo, sav) != 0) { IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); goto bad; } /* * decrypt the packet. */ if (!algo->decrypt) panic("internal error: no decrypt function"); if ((*algo->decrypt)(m, off, sav, algo, ivlen)) { /* m is already freed */ m = NULL; ipseclog((LOG_ERR, "decrypt fail in IPv6 ESP input: %s\n", ipsec_logsastr(sav))); IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); goto bad; } IPSEC_STAT_INCREMENT(ipsec6stat.in_esphist[sav->alg_enc]); m->m_flags |= M_DECRYPTED; /* * find the trailer of the ESP. */ m_copydata(m, m->m_pkthdr.len - sizeof(esptail), sizeof(esptail), (caddr_t)&esptail); nxt = esptail.esp_nxt; taillen = esptail.esp_padlen + sizeof(esptail); if (m->m_pkthdr.len < taillen || m->m_pkthdr.len - taillen < sizeof(struct ip6_hdr)) { /*?*/ ipseclog((LOG_WARNING, "bad pad length in IPv6 ESP input: %s %s\n", ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); goto bad; } /* strip off the trailing pad area. */ m_adj(m, -taillen); ip6 = mtod(m, struct ip6_hdr *); ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - taillen); if (sav->utun_is_keepalive_fn) { if (sav->utun_is_keepalive_fn(sav->utun_pcb, &m, nxt, sav->flags, (off + esplen + ivlen))) { if (m) { // not really bad, we just wanna exit IPSEC_STAT_INCREMENT(ipsec6stat.in_success); m = NULL; } goto bad; } } /* was it transmitted over the IPsec tunnel SA? */ if (ipsec6_tunnel_validate(m, off + esplen + ivlen, nxt, sav)) { ifaddr_t ifa; struct sockaddr_storage addr; /* * strip off all the headers that precedes ESP header. * IP6 xx ESP IP6' payload -> IP6' payload * * XXX more sanity checks * XXX relationship with gif? */ u_int32_t flowinfo; /*net endian*/ flowinfo = ip6->ip6_flow; m_adj(m, off + esplen + ivlen); if (m->m_len < sizeof(*ip6)) { #ifndef PULLDOWN_TEST /* * m_pullup is prohibited in KAME IPv6 input processing * but there's no other way! */ #else /* okay to pullup in m_pulldown style */ #endif m = m_pullup(m, sizeof(*ip6)); if (!m) { IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); goto bad; } } 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_ERR, "ipsec tunnel address mismatch " "in IPv6 ESP input: %s %s\n", ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); goto bad; } key_sa_recordxfer(sav, m); if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0 || ipsec_addhist(m, IPPROTO_IPV6, 0) != 0) { IPSEC_STAT_INCREMENT(ipsec6stat.in_nomem); goto bad; } if (ip6_doscopedroute) { struct sockaddr_in6 *ip6addr; bzero(&addr, sizeof(addr)); ip6addr = (__typeof__(ip6addr))&addr; ip6addr->sin6_family = AF_INET6; ip6addr->sin6_len = sizeof(*ip6addr); ip6addr->sin6_addr = ip6->ip6_dst; // update the receiving interface address based on the inner address ifa = ifa_ifwithaddr((struct sockaddr *)&addr); if (ifa) { m->m_pkthdr.rcvif = ifa->ifa_ifp; IFA_REMREF(ifa); } } // Input via IPSec interface if (sav->sah->ipsec_if != NULL) { if (ipsec_inject_inbound_packet(sav->sah->ipsec_if, m) == 0) { m = NULL; nxt = IPPROTO_DONE; goto done; } else { goto bad; } } if (sav->utun_in_fn) { if (!(sav->utun_in_fn(sav->utun_pcb, &m, PF_INET6))) { m = NULL; // we just wanna exit since packet has been completely processed goto bad; } } if (proto_input(PF_INET6, m) != 0) goto bad; nxt = IPPROTO_DONE; } else { /* * strip off ESP header and IV. * even in m_pulldown case, we need to strip off ESP so that * we can always compute checksum for AH correctly. */ size_t stripsiz; char *prvnxtp; /* * Set the next header field of the previous header correctly. */ prvnxtp = ip6_get_prevhdr(m, off); /* XXX */ *prvnxtp = nxt; stripsiz = esplen + ivlen; ip6 = mtod(m, struct ip6_hdr *); 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 bad; } m_adj(n, stripsiz); /* m_cat does not update m_pkthdr.len */ m->m_pkthdr.len += n->m_pkthdr.len; m_cat(m, n); } #ifndef PULLDOWN_TEST /* * KAME requires that the packet to be contiguous on the * mbuf. We need to make that sure. * this kind of code should be avoided. * XXX other conditions to avoid running this part? */ if (m->m_len != m->m_pkthdr.len) { struct mbuf *n = NULL; int maxlen; MGETHDR(n, M_DONTWAIT, MT_HEADER); /* MAC-OK */ maxlen = MHLEN; if (n) M_COPY_PKTHDR(n, m); if (n && m->m_pkthdr.len > maxlen) { MCLGET(n, M_DONTWAIT); maxlen = MCLBYTES; if ((n->m_flags & M_EXT) == 0) { m_free(n); n = NULL; } } if (!n) { printf("esp6_input: mbuf allocation failed\n"); goto bad; } if (m->m_pkthdr.len <= maxlen) { m_copydata(m, 0, m->m_pkthdr.len, mtod(n, caddr_t)); n->m_len = m->m_pkthdr.len; n->m_pkthdr.len = m->m_pkthdr.len; n->m_next = NULL; m_freem(m); } else { m_copydata(m, 0, maxlen, mtod(n, caddr_t)); n->m_len = maxlen; n->m_pkthdr.len = m->m_pkthdr.len; n->m_next = m; m_adj(m, maxlen); m->m_flags &= ~M_PKTHDR; } m = n; } #endif ip6 = mtod(m, struct ip6_hdr *); ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - stripsiz); key_sa_recordxfer(sav, m); if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0) { IPSEC_STAT_INCREMENT(ipsec6stat.in_nomem); goto bad; } // Input via IPSec interface if (sav->sah->ipsec_if != NULL) { if (ipsec_inject_inbound_packet(sav->sah->ipsec_if, m) == 0) { m = NULL; nxt = IPPROTO_DONE; goto done; } else { goto bad; } } if (sav->utun_in_fn) { if (!(sav->utun_in_fn(sav->utun_pcb, &m, PF_INET6))) { m = NULL; // we just wanna exit since packet has been completely processed goto bad; } } } done: *offp = off; *mp = m; if (sav) { KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP esp6_input call free SA:0x%llx\n", (uint64_t)VM_KERNEL_ADDRPERM(sav))); key_freesav(sav, KEY_SADB_UNLOCKED); } IPSEC_STAT_INCREMENT(ipsec6stat.in_success); return nxt; bad: if (sav) { KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP esp6_input call free SA:0x%llx\n", (uint64_t)VM_KERNEL_ADDRPERM(sav))); key_freesav(sav, KEY_SADB_UNLOCKED); } if (m) m_freem(m); return IPPROTO_DONE; } void esp6_ctlinput(cmd, sa, d) int cmd; struct sockaddr *sa; void *d; { const struct newesp *espp; struct newesp esp; struct ip6ctlparam *ip6cp = NULL, ip6cp1; struct secasvar *sav; struct ip6_hdr *ip6; struct mbuf *m; 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) { /* * Notify the error to all possible sockets via pfctlinput2. * Since the upper layer information (such as protocol type, * source and destination ports) is embedded in the encrypted * data and might have been cut, we can't directly call * an upper layer ctlinput function. However, the pcbnotify * function will consider source and destination addresses * as well as the flow info value, and may be able to find * some PCB that should be notified. * Although pfctlinput2 will call esp6_ctlinput(), there is * no possibility of an infinite loop of function calls, * because we don't pass the inner IPv6 header. */ bzero(&ip6cp1, sizeof(ip6cp1)); ip6cp1.ip6c_src = ip6cp->ip6c_src; pfctlinput2(cmd, sa, (void *)&ip6cp1); /* * Then go to special cases that need ESP header information. * 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(esp)) return; if (m->m_len < off + sizeof(esp)) { /* * this should be rare case, * so we compromise on this copy... */ m_copydata(m, off, sizeof(esp), (caddr_t)&esp); espp = &esp; } else espp = (struct newesp*)(void *)(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. */ sa6_src = ip6cp->ip6c_src; sa6_dst = (struct sockaddr_in6 *)(void *)sa; sav = key_allocsa(AF_INET6, (caddr_t)&sa6_src->sin6_addr, (caddr_t)&sa6_dst->sin6_addr, IPPROTO_ESP, espp->esp_spi); if (sav) { if (sav->state == SADB_SASTATE_MATURE || sav->state == SADB_SASTATE_DYING) valid++; key_freesav(sav, KEY_SADB_LOCKED); } /* 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); } } else { /* we normally notify any pcb here */ } } #endif /* INET6 */