/* $FreeBSD$ */ /* $OpenBSD: ipsec_input.c,v 1.63 2003/02/20 18:35:43 deraadt Exp $ */ /*- * The authors of this code are John Ioannidis (ji@tla.org), * Angelos D. Keromytis (kermit@csd.uch.gr) and * Niels Provos (provos@physnet.uni-hamburg.de). * * This code was written by John Ioannidis for BSD/OS in Athens, Greece, * in November 1995. * * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996, * by Angelos D. Keromytis. * * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis * and Niels Provos. * * Additional features in 1999 by Angelos D. Keromytis. * * Copyright (C) 1995, 1996, 1997, 1998, 1999 by John Ioannidis, * Angelos D. Keromytis and Niels Provos. * Copyright (c) 2001, Angelos D. Keromytis. * * Permission to use, copy, and modify this software with or without fee * is hereby granted, provided that this entire notice is included in * all copies of any software which is or includes a copy or * modification of this software. * You may use this code under the GNU public license if you so wish. Please * contribute changes back to the authors under this freer than GPL license * so that we may further the use of strong encryption without limitations to * all. * * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR * PURPOSE. */ /* * IPsec input processing. */ #include "opt_inet.h" #include "opt_inet6.h" #include "opt_ipsec.h" #include "opt_enc.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef INET6 #include #endif #include #ifdef INET6 #include #endif #include #ifdef INET6 #include #endif #include #include #include #include #include #include #include #include #include #include #ifdef DEV_ENC #include #endif #define IPSEC_ISTAT(proto, name) do { \ if ((proto) == IPPROTO_ESP) \ ESPSTAT_INC(esps_##name); \ else if ((proto) == IPPROTO_AH) \ AHSTAT_INC(ahs_##name); \ else \ IPCOMPSTAT_INC(ipcomps_##name); \ } while (0) #ifdef INET static void ipsec4_common_ctlinput(int, struct sockaddr *, void *, int); #endif /* * ipsec_common_input gets called when an IPsec-protected packet * is received by IPv4 or IPv6. Its job is to find the right SA * and call the appropriate transform. The transform callback * takes care of further processing (like ingress filtering). */ int ipsec_common_input(struct mbuf *m, int skip, int protoff, int af, int sproto) { char buf[INET6_ADDRSTRLEN]; union sockaddr_union dst_address; struct secasvar *sav; u_int32_t spi; int error; #ifdef INET #ifdef IPSEC_NAT_T struct m_tag *tag; #endif #endif IPSEC_ISTAT(sproto, input); IPSEC_ASSERT(m != NULL, ("null packet")); IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH || sproto == IPPROTO_IPCOMP, ("unexpected security protocol %u", sproto)); if ((sproto == IPPROTO_ESP && !V_esp_enable) || (sproto == IPPROTO_AH && !V_ah_enable) || (sproto == IPPROTO_IPCOMP && !V_ipcomp_enable)) { m_freem(m); IPSEC_ISTAT(sproto, pdrops); return EOPNOTSUPP; } if (m->m_pkthdr.len - skip < 2 * sizeof (u_int32_t)) { m_freem(m); IPSEC_ISTAT(sproto, hdrops); DPRINTF(("%s: packet too small\n", __func__)); return EINVAL; } /* Retrieve the SPI from the relevant IPsec header */ if (sproto == IPPROTO_ESP) m_copydata(m, skip, sizeof(u_int32_t), (caddr_t) &spi); else if (sproto == IPPROTO_AH) m_copydata(m, skip + sizeof(u_int32_t), sizeof(u_int32_t), (caddr_t) &spi); else if (sproto == IPPROTO_IPCOMP) { u_int16_t cpi; m_copydata(m, skip + sizeof(u_int16_t), sizeof(u_int16_t), (caddr_t) &cpi); spi = ntohl(htons(cpi)); } /* * Find the SA and (indirectly) call the appropriate * kernel crypto routine. The resulting mbuf chain is a valid * IP packet ready to go through input processing. */ bzero(&dst_address, sizeof (dst_address)); dst_address.sa.sa_family = af; switch (af) { #ifdef INET case AF_INET: dst_address.sin.sin_len = sizeof(struct sockaddr_in); m_copydata(m, offsetof(struct ip, ip_dst), sizeof(struct in_addr), (caddr_t) &dst_address.sin.sin_addr); #ifdef IPSEC_NAT_T /* Find the source port for NAT-T; see udp*_espdecap. */ tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL); if (tag != NULL) dst_address.sin.sin_port = ((u_int16_t *)(tag + 1))[1]; #endif /* IPSEC_NAT_T */ break; #endif /* INET */ #ifdef INET6 case AF_INET6: dst_address.sin6.sin6_len = sizeof(struct sockaddr_in6); m_copydata(m, offsetof(struct ip6_hdr, ip6_dst), sizeof(struct in6_addr), (caddr_t) &dst_address.sin6.sin6_addr); /* We keep addresses in SADB without embedded scope id */ if (IN6_IS_SCOPE_LINKLOCAL(&dst_address.sin6.sin6_addr)) { /* XXX: sa6_recoverscope() */ dst_address.sin6.sin6_scope_id = ntohs(dst_address.sin6.sin6_addr.s6_addr16[1]); dst_address.sin6.sin6_addr.s6_addr16[1] = 0; } break; #endif /* INET6 */ default: DPRINTF(("%s: unsupported protocol family %u\n", __func__, af)); m_freem(m); IPSEC_ISTAT(sproto, nopf); return EPFNOSUPPORT; } /* NB: only pass dst since key_allocsa follows RFC2401 */ sav = KEY_ALLOCSA(&dst_address, sproto, spi); if (sav == NULL) { DPRINTF(("%s: no key association found for SA %s/%08lx/%u\n", __func__, ipsec_address(&dst_address, buf, sizeof(buf)), (u_long) ntohl(spi), sproto)); IPSEC_ISTAT(sproto, notdb); m_freem(m); return ENOENT; } if (sav->tdb_xform == NULL) { DPRINTF(("%s: attempted to use uninitialized SA %s/%08lx/%u\n", __func__, ipsec_address(&dst_address, buf, sizeof(buf)), (u_long) ntohl(spi), sproto)); IPSEC_ISTAT(sproto, noxform); KEY_FREESAV(&sav); m_freem(m); return ENXIO; } /* * Call appropriate transform and return -- callback takes care of * everything else. */ error = (*sav->tdb_xform->xf_input)(m, sav, skip, protoff); KEY_FREESAV(&sav); return error; } #ifdef INET void ah4_input(struct mbuf *m, int off) { ipsec_common_input(m, off, offsetof(struct ip, ip_p), AF_INET, IPPROTO_AH); } void ah4_ctlinput(int cmd, struct sockaddr *sa, void *v) { if (sa->sa_family == AF_INET && sa->sa_len == sizeof(struct sockaddr_in)) ipsec4_common_ctlinput(cmd, sa, v, IPPROTO_AH); } void esp4_input(struct mbuf *m, int off) { ipsec_common_input(m, off, offsetof(struct ip, ip_p), AF_INET, IPPROTO_ESP); } void esp4_ctlinput(int cmd, struct sockaddr *sa, void *v) { if (sa->sa_family == AF_INET && sa->sa_len == sizeof(struct sockaddr_in)) ipsec4_common_ctlinput(cmd, sa, v, IPPROTO_ESP); } void ipcomp4_input(struct mbuf *m, int off) { ipsec_common_input(m, off, offsetof(struct ip, ip_p), AF_INET, IPPROTO_IPCOMP); } /* * IPsec input callback for INET protocols. * This routine is called as the transform callback. * Takes care of filtering and other sanity checks on * the processed packet. */ int ipsec4_common_input_cb(struct mbuf *m, struct secasvar *sav, int skip, int protoff) { char buf[INET6_ADDRSTRLEN]; int prot, af, sproto, isr_prot; struct ip *ip; struct m_tag *mtag; struct tdb_ident *tdbi; struct secasindex *saidx; int error; #ifdef INET6 #ifdef notyet char ip6buf[INET6_ADDRSTRLEN]; #endif #endif IPSEC_ASSERT(m != NULL, ("null mbuf")); IPSEC_ASSERT(sav != NULL, ("null SA")); IPSEC_ASSERT(sav->sah != NULL, ("null SAH")); saidx = &sav->sah->saidx; af = saidx->dst.sa.sa_family; IPSEC_ASSERT(af == AF_INET, ("unexpected af %u", af)); sproto = saidx->proto; IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH || sproto == IPPROTO_IPCOMP, ("unexpected security protocol %u", sproto)); /* Sanity check */ if (m == NULL) { DPRINTF(("%s: null mbuf", __func__)); IPSEC_ISTAT(sproto, badkcr); KEY_FREESAV(&sav); return EINVAL; } if (skip != 0) { /* * Fix IPv4 header * XXXGL: do we need this entire block? */ if (m->m_len < skip && (m = m_pullup(m, skip)) == NULL) { DPRINTF(("%s: processing failed for SA %s/%08lx\n", __func__, ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)), (u_long) ntohl(sav->spi))); IPSEC_ISTAT(sproto, hdrops); error = ENOBUFS; goto bad; } ip = mtod(m, struct ip *); ip->ip_len = htons(m->m_pkthdr.len); ip->ip_sum = 0; ip->ip_sum = in_cksum(m, ip->ip_hl << 2); } else { ip = mtod(m, struct ip *); } prot = ip->ip_p; #ifdef DEV_ENC encif->if_ipackets++; encif->if_ibytes += m->m_pkthdr.len; /* Pass the mbuf to enc0 for bpf and pfil. */ ipsec_bpf(m, sav, AF_INET, ENC_IN|ENC_BEFORE); if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_BEFORE)) != 0) return (error); ip = mtod(m, struct ip *); #endif /* DEV_ENC */ /* IP-in-IP encapsulation */ if (prot == IPPROTO_IPIP && saidx->mode != IPSEC_MODE_TRANSPORT) { if (m->m_pkthdr.len - skip < sizeof(struct ip)) { IPSEC_ISTAT(sproto, hdrops); error = EINVAL; goto bad; } /* enc0: strip outer IPv4 header */ m_striphdr(m, 0, ip->ip_hl << 2); #ifdef notyet /* XXX PROXY address isn't recorded in SAH */ /* * Check that the inner source address is the same as * the proxy address, if available. */ if ((saidx->proxy.sa.sa_family == AF_INET && saidx->proxy.sin.sin_addr.s_addr != INADDR_ANY && ipn.ip_src.s_addr != saidx->proxy.sin.sin_addr.s_addr) || (saidx->proxy.sa.sa_family != AF_INET && saidx->proxy.sa.sa_family != 0)) { DPRINTF(("%s: inner source address %s doesn't " "correspond to expected proxy source %s, " "SA %s/%08lx\n", __func__, inet_ntoa4(ipn.ip_src), ipsp_address(saidx->proxy), ipsp_address(saidx->dst), (u_long) ntohl(sav->spi))); IPSEC_ISTAT(sproto, pdrops); error = EACCES; goto bad; } #endif /* notyet */ } #ifdef INET6 /* IPv6-in-IP encapsulation. */ else if (prot == IPPROTO_IPV6 && saidx->mode != IPSEC_MODE_TRANSPORT) { if (m->m_pkthdr.len - skip < sizeof(struct ip6_hdr)) { IPSEC_ISTAT(sproto, hdrops); error = EINVAL; goto bad; } /* enc0: strip IPv4 header, keep IPv6 header only */ m_striphdr(m, 0, ip->ip_hl << 2); #ifdef notyet /* * Check that the inner source address is the same as * the proxy address, if available. */ if ((saidx->proxy.sa.sa_family == AF_INET6 && !IN6_IS_ADDR_UNSPECIFIED(&saidx->proxy.sin6.sin6_addr) && !IN6_ARE_ADDR_EQUAL(&ip6n.ip6_src, &saidx->proxy.sin6.sin6_addr)) || (saidx->proxy.sa.sa_family != AF_INET6 && saidx->proxy.sa.sa_family != 0)) { DPRINTF(("%s: inner source address %s doesn't " "correspond to expected proxy source %s, " "SA %s/%08lx\n", __func__, ip6_sprintf(ip6buf, &ip6n.ip6_src), ipsec_address(&saidx->proxy), ipsec_address(&saidx->dst), (u_long) ntohl(sav->spi))); IPSEC_ISTAT(sproto, pdrops); error = EACCES; goto bad; } #endif /* notyet */ } #endif /* INET6 */ else if (prot != IPPROTO_IPV6 && saidx->mode == IPSEC_MODE_ANY) { /* * When mode is wildcard, inner protocol is IPv6 and * we have no INET6 support - drop this packet a bit later. * In other cases we assume transport mode and outer * header was already stripped in xform_xxx_cb. */ prot = IPPROTO_IPIP; } /* * Record what we've done to the packet (under what SA it was * processed). */ if (sproto != IPPROTO_IPCOMP) { mtag = m_tag_get(PACKET_TAG_IPSEC_IN_DONE, sizeof(struct tdb_ident), M_NOWAIT); if (mtag == NULL) { DPRINTF(("%s: failed to get tag\n", __func__)); IPSEC_ISTAT(sproto, hdrops); error = ENOMEM; goto bad; } tdbi = (struct tdb_ident *)(mtag + 1); bcopy(&saidx->dst, &tdbi->dst, saidx->dst.sa.sa_len); tdbi->proto = sproto; tdbi->spi = sav->spi; /* Cache those two for enc(4) in xform_ipip. */ tdbi->alg_auth = sav->alg_auth; tdbi->alg_enc = sav->alg_enc; m_tag_prepend(m, mtag); } key_sa_recordxfer(sav, m); /* record data transfer */ /* * In transport mode requeue decrypted mbuf back to IPv4 protocol * handler. This is necessary to correctly expose rcvif. */ if (saidx->mode == IPSEC_MODE_TRANSPORT) prot = IPPROTO_IPIP; #ifdef DEV_ENC /* * Pass the mbuf to enc0 for bpf and pfil. */ if (prot == IPPROTO_IPIP) ipsec_bpf(m, sav, AF_INET, ENC_IN|ENC_AFTER); #ifdef INET6 if (prot == IPPROTO_IPV6) ipsec_bpf(m, sav, AF_INET6, ENC_IN|ENC_AFTER); #endif if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_AFTER)) != 0) return (error); #endif /* DEV_ENC */ /* * Re-dispatch via software interrupt. */ switch (prot) { case IPPROTO_IPIP: isr_prot = NETISR_IP; break; #ifdef INET6 case IPPROTO_IPV6: isr_prot = NETISR_IPV6; break; #endif default: DPRINTF(("%s: cannot handle inner ip proto %d\n", __func__, prot)); IPSEC_ISTAT(sproto, nopf); error = EPFNOSUPPORT; goto bad; } error = netisr_queue_src(isr_prot, (uintptr_t)sav->spi, m); if (error) { IPSEC_ISTAT(sproto, qfull); DPRINTF(("%s: queue full; proto %u packet dropped\n", __func__, sproto)); return error; } return 0; bad: m_freem(m); return error; } void ipsec4_common_ctlinput(int cmd, struct sockaddr *sa, void *v, int proto) { /* XXX nothing just yet */ } #endif /* INET */ #ifdef INET6 /* IPv6 AH wrapper. */ int ipsec6_common_input(struct mbuf **mp, int *offp, int proto) { int l = 0; int protoff; struct ip6_ext ip6e; if (*offp < sizeof(struct ip6_hdr)) { DPRINTF(("%s: bad offset %u\n", __func__, *offp)); return IPPROTO_DONE; } else if (*offp == sizeof(struct ip6_hdr)) { protoff = offsetof(struct ip6_hdr, ip6_nxt); } else { /* Chase down the header chain... */ protoff = sizeof(struct ip6_hdr); do { protoff += l; m_copydata(*mp, protoff, sizeof(ip6e), (caddr_t) &ip6e); if (ip6e.ip6e_nxt == IPPROTO_AH) l = (ip6e.ip6e_len + 2) << 2; else l = (ip6e.ip6e_len + 1) << 3; IPSEC_ASSERT(l > 0, ("l went zero or negative")); } while (protoff + l < *offp); /* Malformed packet check */ if (protoff + l != *offp) { DPRINTF(("%s: bad packet header chain, protoff %u, " "l %u, off %u\n", __func__, protoff, l, *offp)); IPSEC_ISTAT(proto, hdrops); m_freem(*mp); *mp = NULL; return IPPROTO_DONE; } protoff += offsetof(struct ip6_ext, ip6e_nxt); } (void) ipsec_common_input(*mp, *offp, protoff, AF_INET6, proto); return IPPROTO_DONE; } /* * IPsec input callback, called by the transform callback. Takes care of * filtering and other sanity checks on the processed packet. */ int ipsec6_common_input_cb(struct mbuf *m, struct secasvar *sav, int skip, int protoff) { char buf[INET6_ADDRSTRLEN]; int prot, af, sproto; struct ip6_hdr *ip6; struct m_tag *mtag; struct tdb_ident *tdbi; struct secasindex *saidx; int nxt, isr_prot; u_int8_t nxt8; int error, nest; #ifdef notyet char ip6buf[INET6_ADDRSTRLEN]; #endif IPSEC_ASSERT(m != NULL, ("null mbuf")); IPSEC_ASSERT(sav != NULL, ("null SA")); IPSEC_ASSERT(sav->sah != NULL, ("null SAH")); saidx = &sav->sah->saidx; af = saidx->dst.sa.sa_family; IPSEC_ASSERT(af == AF_INET6, ("unexpected af %u", af)); sproto = saidx->proto; IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH || sproto == IPPROTO_IPCOMP, ("unexpected security protocol %u", sproto)); /* Sanity check */ if (m == NULL) { DPRINTF(("%s: null mbuf", __func__)); IPSEC_ISTAT(sproto, badkcr); error = EINVAL; goto bad; } /* Fix IPv6 header */ if (m->m_len < sizeof(struct ip6_hdr) && (m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) { DPRINTF(("%s: processing failed for SA %s/%08lx\n", __func__, ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)), (u_long) ntohl(sav->spi))); IPSEC_ISTAT(sproto, hdrops); error = EACCES; goto bad; } ip6 = mtod(m, struct ip6_hdr *); ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); /* Save protocol */ m_copydata(m, protoff, 1, &nxt8); prot = nxt8; #ifdef DEV_ENC encif->if_ipackets++; encif->if_ibytes += m->m_pkthdr.len; /* Pass the mbuf to enc0 for bpf and pfil. */ ipsec_bpf(m, sav, AF_INET6, ENC_IN|ENC_BEFORE); if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_BEFORE)) != 0) return (error); #endif /* DEV_ENC */ /* IPv6-in-IP encapsulation */ if (prot == IPPROTO_IPV6 && saidx->mode != IPSEC_MODE_TRANSPORT) { if (m->m_pkthdr.len - skip < sizeof(struct ip6_hdr)) { IPSEC_ISTAT(sproto, hdrops); error = EINVAL; goto bad; } /* ip6n will now contain the inner IPv6 header. */ m_striphdr(m, 0, skip); skip = 0; #ifdef notyet /* * Check that the inner source address is the same as * the proxy address, if available. */ if ((saidx->proxy.sa.sa_family == AF_INET6 && !IN6_IS_ADDR_UNSPECIFIED(&saidx->proxy.sin6.sin6_addr) && !IN6_ARE_ADDR_EQUAL(&ip6n.ip6_src, &saidx->proxy.sin6.sin6_addr)) || (saidx->proxy.sa.sa_family != AF_INET6 && saidx->proxy.sa.sa_family != 0)) { DPRINTF(("%s: inner source address %s doesn't " "correspond to expected proxy source %s, " "SA %s/%08lx\n", __func__, ip6_sprintf(ip6buf, &ip6n.ip6_src), ipsec_address(&saidx->proxy), ipsec_address(&saidx->dst), (u_long) ntohl(sav->spi))); IPSEC_ISTAT(sproto, pdrops); error = EACCES; goto bad; } #endif /* notyet */ } #ifdef INET /* IP-in-IP encapsulation */ else if (prot == IPPROTO_IPIP && saidx->mode != IPSEC_MODE_TRANSPORT) { if (m->m_pkthdr.len - skip < sizeof(struct ip)) { IPSEC_ISTAT(sproto, hdrops); error = EINVAL; goto bad; } /* ipn will now contain the inner IPv4 header */ m_striphdr(m, 0, skip); skip = 0; #ifdef notyet /* * Check that the inner source address is the same as * the proxy address, if available. */ if ((saidx->proxy.sa.sa_family == AF_INET && saidx->proxy.sin.sin_addr.s_addr != INADDR_ANY && ipn.ip_src.s_addr != saidx->proxy.sin.sin_addr.s_addr) || (saidx->proxy.sa.sa_family != AF_INET && saidx->proxy.sa.sa_family != 0)) { DPRINTF(("%s: inner source address %s doesn't " "correspond to expected proxy source %s, " "SA %s/%08lx\n", __func__, inet_ntoa4(ipn.ip_src), ipsec_address(&saidx->proxy), ipsec_address(&saidx->dst), (u_long) ntohl(sav->spi))); IPSEC_ISTAT(sproto, pdrops); error = EACCES; goto bad; } #endif /* notyet */ } #endif /* INET */ else { prot = IPPROTO_IPV6; /* for correct BPF processing */ } /* * Record what we've done to the packet (under what SA it was * processed). */ if (sproto != IPPROTO_IPCOMP) { mtag = m_tag_get(PACKET_TAG_IPSEC_IN_DONE, sizeof(struct tdb_ident), M_NOWAIT); if (mtag == NULL) { DPRINTF(("%s: failed to get tag\n", __func__)); IPSEC_ISTAT(sproto, hdrops); error = ENOMEM; goto bad; } tdbi = (struct tdb_ident *)(mtag + 1); bcopy(&saidx->dst, &tdbi->dst, sizeof(union sockaddr_union)); tdbi->proto = sproto; tdbi->spi = sav->spi; /* Cache those two for enc(4) in xform_ipip. */ tdbi->alg_auth = sav->alg_auth; tdbi->alg_enc = sav->alg_enc; m_tag_prepend(m, mtag); } key_sa_recordxfer(sav, m); #ifdef DEV_ENC /* * Pass the mbuf to enc0 for bpf and pfil. */ #ifdef INET if (prot == IPPROTO_IPIP) ipsec_bpf(m, sav, AF_INET, ENC_IN|ENC_AFTER); #endif if (prot == IPPROTO_IPV6) ipsec_bpf(m, sav, AF_INET6, ENC_IN|ENC_AFTER); if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_AFTER)) != 0) return (error); #endif /* DEV_ENC */ if (skip == 0) { /* * We stripped outer IPv6 header. * Now we should requeue decrypted packet via netisr. */ switch (prot) { #ifdef INET case IPPROTO_IPIP: isr_prot = NETISR_IP; break; #endif case IPPROTO_IPV6: isr_prot = NETISR_IPV6; break; default: DPRINTF(("%s: cannot handle inner ip proto %d\n", __func__, prot)); IPSEC_ISTAT(sproto, nopf); error = EPFNOSUPPORT; goto bad; } error = netisr_queue_src(isr_prot, (uintptr_t)sav->spi, m); if (error) { IPSEC_ISTAT(sproto, qfull); DPRINTF(("%s: queue full; proto %u packet dropped\n", __func__, sproto)); } return (error); } /* * See the end of ip6_input for this logic. * IPPROTO_IPV[46] case will be processed just like other ones */ nest = 0; nxt = nxt8; while (nxt != IPPROTO_DONE) { if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) { IP6STAT_INC(ip6s_toomanyhdr); error = EINVAL; goto bad; } /* * Protection against faulty packet - there should be * more sanity checks in header chain processing. */ if (m->m_pkthdr.len < skip) { IP6STAT_INC(ip6s_tooshort); in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); error = EINVAL; goto bad; } /* * Enforce IPsec policy checking if we are seeing last header. * note that we do not visit this with protocols with pcb layer * code - like udp/tcp/raw ip. */ if ((inet6sw[ip6_protox[nxt]].pr_flags & PR_LASTHDR) != 0 && ipsec6_in_reject(m, NULL)) { error = EINVAL; goto bad; } nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &skip, nxt); } return 0; bad: if (m) m_freem(m); return error; } void esp6_ctlinput(int cmd, struct sockaddr *sa, void *d) { struct ip6ctlparam *ip6cp = NULL; struct mbuf *m = NULL; struct ip6_hdr *ip6; int off; 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; off = 0; /* calm gcc */ } if (ip6 != NULL) { struct ip6ctlparam ip6cp1; /* * 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. */ if (cmd == PRC_MSGSIZE) { struct secasvar *sav; u_int32_t spi; int valid; /* check header length before using m_copydata */ if (m->m_pkthdr.len < off + sizeof (struct esp)) return; m_copydata(m, off + offsetof(struct esp, esp_spi), sizeof(u_int32_t), (caddr_t) &spi); /* * Check to see if we have a valid SA corresponding to * the address in the ICMP message payload. */ sav = KEY_ALLOCSA((union sockaddr_union *)sa, IPPROTO_ESP, spi); valid = (sav != NULL); if (sav) KEY_FREESAV(&sav); /* XXX Further validation? */ /* * Depending on whether the SA is "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(ip6cp, valid); } } else { /* we normally notify any pcb here */ } } #endif /* INET6 */