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IABSD.fr/src/sys/netinet/ipsec_input.c
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- sys/netinet/ipsec_input.c
-
/* $OpenBSD: ipsec_input.c,v 1.221 2025/07/08 00:47:41 jsg 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. */ #include "pf.h" #include "sec.h" #include <sys/param.h> #include <sys/systm.h> #include <sys/protosw.h> #include <sys/mbuf.h> #include <sys/socket.h> #include <sys/sysctl.h> #include <sys/timeout.h> #include <net/if.h> #include <net/if_var.h> #include <net/bpf.h> #include <netinet/in.h> #include <netinet/ip.h> #include <netinet/ip_var.h> #include <netinet/ip_icmp.h> #include <netinet/tcp.h> #include <netinet/udp.h> #if NPF > 0 #include <net/pfvar.h> #endif #if NSEC > 0 #include <net/if_sec.h> #endif #ifdef INET6 #include <netinet/ip6.h> #include <netinet6/ip6_var.h> #endif /* INET6 */ #include <netinet/ip_ipsp.h> #include <netinet/ip_esp.h> #include <netinet/ip_ah.h> #include <netinet/ip_ipcomp.h> #include <net/if_enc.h> #include "bpfilter.h" /* * Locks used to protect data: * a atomic */ void ipsec_common_ctlinput(u_int, int, struct sockaddr *, void *, int); #ifdef ENCDEBUG #define DPRINTF(fmt, args...) \ do { \ if (atomic_load_int(&encdebug)) \ printf("%s: " fmt "\n", __func__, ## args); \ } while (0) #else #define DPRINTF(fmt, args...) \ do { } while (0) #endif /* sysctl variables */ int encdebug = 0; /* [a] */ int ipsec_keep_invalid = IPSEC_DEFAULT_EMBRYONIC_SA_TIMEOUT; /* [a] */ int ipsec_require_pfs = IPSEC_DEFAULT_PFS; /* [a] */ int ipsec_soft_allocations = IPSEC_DEFAULT_SOFT_ALLOCATIONS; /* [a] */ int ipsec_exp_allocations = IPSEC_DEFAULT_EXP_ALLOCATIONS; /* [a] */ int ipsec_soft_bytes = IPSEC_DEFAULT_SOFT_BYTES; /* [a] */ int ipsec_exp_bytes = IPSEC_DEFAULT_EXP_BYTES; /* [a] */ int ipsec_soft_timeout = IPSEC_DEFAULT_SOFT_TIMEOUT; /* [a] */ int ipsec_exp_timeout = IPSEC_DEFAULT_EXP_TIMEOUT; /* [a] */ int ipsec_soft_first_use = IPSEC_DEFAULT_SOFT_FIRST_USE; /* [a] */ int ipsec_exp_first_use = IPSEC_DEFAULT_EXP_FIRST_USE; /* [a] */ int ipsec_expire_acquire = IPSEC_DEFAULT_EXPIRE_ACQUIRE; /* [a] */ int esp_enable = 1; /* [a] */ int ah_enable = 1; /* [a] */ int ipcomp_enable = 0; /* [a] */ const struct sysctl_bounded_args espctl_vars[] = { {ESPCTL_ENABLE, &esp_enable, 0, 1}, {ESPCTL_UDPENCAP_ENABLE, &udpencap_enable, 0, 1}, {ESPCTL_UDPENCAP_PORT, &udpencap_port, 0, 65535}, }; const struct sysctl_bounded_args ahctl_vars[] = { {AHCTL_ENABLE, &ah_enable, 0, 1}, }; const struct sysctl_bounded_args ipcompctl_vars[] = { {IPCOMPCTL_ENABLE, &ipcomp_enable, 0, 1}, }; struct cpumem *espcounters; struct cpumem *ahcounters; struct cpumem *ipcompcounters; struct cpumem *ipseccounters; struct ipsec_sysctl_algorithm { const char *name; int val; }; const struct ipsec_sysctl_algorithm ipsec_sysctl_enc_algs[] = { {"aes", IPSEC_ENC_AES}, {"aesctr", IPSEC_ENC_AESCTR}, {"3des", IPSEC_ENC_3DES}, {"blowfish", IPSEC_ENC_BLOWFISH}, {"cast128", IPSEC_ENC_CAST128}, {NULL, -1}, }; const struct ipsec_sysctl_algorithm ipsec_sysctl_auth_algs[] = { {"hmac-sha1", IPSEC_AUTH_HMAC_SHA1}, {"hmac-ripemd160", IPSEC_AUTH_HMAC_RIPEMD160}, {"hmac-md5", IPSEC_AUTH_MD5}, {"hmac-sha2-256", IPSEC_AUTH_SHA2_256}, {"hmac-sha2-384", IPSEC_AUTH_SHA2_384}, {"hmac-sha2-512", IPSEC_AUTH_SHA2_512}, {NULL, -1}, }; const struct ipsec_sysctl_algorithm ipsec_sysctl_comp_algs[] = { {"deflate", IPSEC_COMP_DEFLATE}, {NULL, -1}, }; int ipsec_def_enc = IPSEC_ENC_AES; /* [a] */ int ipsec_def_auth = IPSEC_AUTH_HMAC_SHA1; /* [a] */ int ipsec_def_comp = IPSEC_COMP_DEFLATE; /* [a] */ const struct sysctl_bounded_args ipsecctl_vars[] = { { IPSEC_ENCDEBUG, &encdebug, 0, 1 }, { IPSEC_EXPIRE_ACQUIRE, &ipsec_expire_acquire, 0, INT_MAX }, { IPSEC_EMBRYONIC_SA_TIMEOUT, &ipsec_keep_invalid, 0, INT_MAX }, { IPSEC_REQUIRE_PFS, &ipsec_require_pfs, 0, 1 }, { IPSEC_SOFT_ALLOCATIONS, &ipsec_soft_allocations, 0, INT_MAX }, { IPSEC_ALLOCATIONS, &ipsec_exp_allocations, 0, INT_MAX }, { IPSEC_SOFT_BYTES, &ipsec_soft_bytes, 0, INT_MAX }, { IPSEC_BYTES, &ipsec_exp_bytes, 0, INT_MAX }, { IPSEC_TIMEOUT, &ipsec_exp_timeout, 0, INT_MAX }, { IPSEC_SOFT_TIMEOUT, &ipsec_soft_timeout, 0, INT_MAX }, { IPSEC_SOFT_FIRSTUSE, &ipsec_soft_first_use, 0, INT_MAX }, { IPSEC_FIRSTUSE, &ipsec_exp_first_use, 0, INT_MAX }, }; int ipsec_sysctl_algorithm(int, void *, size_t *, void *, size_t); int esp_sysctl_espstat(void *, size_t *, void *); int ah_sysctl_ahstat(void *, size_t *, void *); int ipcomp_sysctl_ipcompstat(void *, size_t *, void *); int ipsec_sysctl_ipsecstat(void *, size_t *, void *); void ipsec_init(void) { espcounters = counters_alloc(esps_ncounters); ahcounters = counters_alloc(ahs_ncounters); ipcompcounters = counters_alloc(ipcomps_ncounters); ipseccounters = counters_alloc(ipsec_ncounters); ipsp_init(); } /* * ipsec_common_input() gets called when we receive an IPsec-protected packet * in IPv4 or IPv6. All it does is find the right TDB and call the appropriate * transform. The callback takes care of further processing (like ingress * filtering). */ int ipsec_common_input(struct mbuf **mp, int skip, int protoff, int af, int sproto, int udpencap, struct netstack *ns) { #define IPSEC_ISTAT(x,y,z) do { \ if (sproto == IPPROTO_ESP) \ espstat_inc(x); \ else if (sproto == IPPROTO_AH) \ ahstat_inc(y); \ else \ ipcompstat_inc(z); \ } while (0) struct mbuf *m = *mp; union sockaddr_union dst_address; struct tdb *tdbp = NULL; u_int32_t spi; u_int16_t cpi; int prot; #ifdef ENCDEBUG char buf[INET6_ADDRSTRLEN]; #endif NET_ASSERT_LOCKED(); ipsecstat_pkt(ipsec_ipackets, ipsec_ibytes, m->m_pkthdr.len); IPSEC_ISTAT(esps_input, ahs_input, ipcomps_input); if ((sproto == IPPROTO_IPCOMP) && (m->m_flags & M_COMP)) { DPRINTF("repeated decompression"); ipcompstat_inc(ipcomps_pdrops); goto drop; } if (m->m_pkthdr.len - skip < 2 * sizeof(u_int32_t)) { DPRINTF("packet too small"); IPSEC_ISTAT(esps_hdrops, ahs_hdrops, ipcomps_hdrops); goto drop; } /* Retrieve the SPI from the relevant IPsec header */ switch (sproto) { case IPPROTO_ESP: m_copydata(m, skip, sizeof(u_int32_t), (caddr_t) &spi); break; case IPPROTO_AH: m_copydata(m, skip + sizeof(u_int32_t), sizeof(u_int32_t), (caddr_t) &spi); break; case IPPROTO_IPCOMP: m_copydata(m, skip + sizeof(u_int16_t), sizeof(u_int16_t), (caddr_t) &cpi); spi = ntohl(htons(cpi)); break; default: panic("%s: unknown/unsupported security protocol %d", __func__, sproto); } /* * Find tunnel control block and (indirectly) call the appropriate * kernel crypto routine. The resulting mbuf chain is a valid * IP packet ready to go through input processing. */ memset(&dst_address, 0, sizeof(dst_address)); dst_address.sa.sa_family = af; switch (af) { 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)); break; #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)); in6_recoverscope(&dst_address.sin6, &dst_address.sin6.sin6_addr); break; #endif /* INET6 */ default: DPRINTF("unsupported protocol family %d", af); IPSEC_ISTAT(esps_nopf, ahs_nopf, ipcomps_nopf); goto drop; } tdbp = gettdb(rtable_l2(m->m_pkthdr.ph_rtableid), spi, &dst_address, sproto); if (tdbp == NULL) { DPRINTF("could not find SA for packet to %s, spi %08x", ipsp_address(&dst_address, buf, sizeof(buf)), ntohl(spi)); IPSEC_ISTAT(esps_notdb, ahs_notdb, ipcomps_notdb); goto drop; } if (tdbp->tdb_flags & TDBF_INVALID) { DPRINTF("attempted to use invalid SA %s/%08x/%u", ipsp_address(&dst_address, buf, sizeof(buf)), ntohl(spi), tdbp->tdb_sproto); IPSEC_ISTAT(esps_invalid, ahs_invalid, ipcomps_invalid); goto drop; } if (udpencap && !(tdbp->tdb_flags & TDBF_UDPENCAP)) { DPRINTF("attempted to use non-udpencap SA %s/%08x/%u", ipsp_address(&dst_address, buf, sizeof(buf)), ntohl(spi), tdbp->tdb_sproto); espstat_inc(esps_udpinval); goto drop; } if (!udpencap && (tdbp->tdb_flags & TDBF_UDPENCAP)) { DPRINTF("attempted to use udpencap SA %s/%08x/%u", ipsp_address(&dst_address, buf, sizeof(buf)), ntohl(spi), tdbp->tdb_sproto); espstat_inc(esps_udpneeded); goto drop; } if (tdbp->tdb_xform == NULL) { DPRINTF("attempted to use uninitialized SA %s/%08x/%u", ipsp_address(&dst_address, buf, sizeof(buf)), ntohl(spi), tdbp->tdb_sproto); IPSEC_ISTAT(esps_noxform, ahs_noxform, ipcomps_noxform); goto drop; } KERNEL_LOCK(); /* Register first use, setup expiration timer. */ if (tdbp->tdb_first_use == 0) { tdbp->tdb_first_use = gettime(); if (tdbp->tdb_flags & TDBF_FIRSTUSE) { if (timeout_add_sec(&tdbp->tdb_first_tmo, tdbp->tdb_exp_first_use)) tdb_ref(tdbp); } if (tdbp->tdb_flags & TDBF_SOFT_FIRSTUSE) { if (timeout_add_sec(&tdbp->tdb_sfirst_tmo, tdbp->tdb_soft_first_use)) tdb_ref(tdbp); } } tdbstat_pkt(tdbp, tdb_ipackets, tdb_ibytes, m->m_pkthdr.len); /* * Call appropriate transform and return -- callback takes care of * everything else. */ prot = (*(tdbp->tdb_xform->xf_input))(mp, tdbp, skip, protoff, ns); if (prot == IPPROTO_DONE) { ipsecstat_inc(ipsec_idrops); tdbstat_inc(tdbp, tdb_idrops); } tdb_unref(tdbp); KERNEL_UNLOCK(); return prot; drop: m_freemp(mp); ipsecstat_inc(ipsec_idrops); if (tdbp != NULL) tdbstat_inc(tdbp, tdb_idrops); tdb_unref(tdbp); return IPPROTO_DONE; } /* * IPsec input callback, called by the transform callback. Takes care of * filtering and other sanity checks on the processed packet. */ int ipsec_common_input_cb(struct mbuf **mp, struct tdb *tdbp, int skip, int protoff, struct netstack *ns) { struct mbuf *m = *mp; int af, sproto; u_int8_t prot; #if NBPFILTER > 0 struct ifnet *encif; #endif struct ip *ip; #ifdef INET6 struct ip6_hdr *ip6; #endif /* INET6 */ struct m_tag *mtag; struct tdb_ident *tdbi; #ifdef ENCDEBUG char buf[INET6_ADDRSTRLEN]; #endif af = tdbp->tdb_dst.sa.sa_family; sproto = tdbp->tdb_sproto; tdbp->tdb_last_used = gettime(); /* Fix IPv4 header */ if (af == AF_INET) { if (m->m_len < skip && (m = *mp = m_pullup(m, skip)) == NULL) { DPRINTF("processing failed for SA %s/%08x", ipsp_address(&tdbp->tdb_dst, buf, sizeof(buf)), ntohl(tdbp->tdb_spi)); IPSEC_ISTAT(esps_hdrops, ahs_hdrops, ipcomps_hdrops); goto baddone; } ip = mtod(m, struct ip *); ip->ip_len = htons(m->m_pkthdr.len); in_hdr_cksum_out(m, NULL); prot = ip->ip_p; } #ifdef INET6 /* Fix IPv6 header */ if (af == AF_INET6) { if (m->m_len < sizeof(struct ip6_hdr) && (m = *mp = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) { DPRINTF("processing failed for SA %s/%08x", ipsp_address(&tdbp->tdb_dst, buf, sizeof(buf)), ntohl(tdbp->tdb_spi)); IPSEC_ISTAT(esps_hdrops, ahs_hdrops, ipcomps_hdrops); goto baddone; } ip6 = mtod(m, struct ip6_hdr *); ip6->ip6_plen = htons(m->m_pkthdr.len - skip); /* Save protocol */ m_copydata(m, protoff, 1, (caddr_t) &prot); } #endif /* INET6 */ /* * Fix TCP/UDP checksum of UDP encapsulated transport mode ESP packet. * (RFC3948 3.1.2) */ if ((af == AF_INET || af == AF_INET6) && (tdbp->tdb_flags & TDBF_UDPENCAP) && (tdbp->tdb_flags & TDBF_TUNNELING) == 0) { u_int16_t cksum; switch (prot) { case IPPROTO_UDP: if (m->m_pkthdr.len < skip + sizeof(struct udphdr)) { IPSEC_ISTAT(esps_hdrops, ahs_hdrops, ipcomps_hdrops); goto baddone; } cksum = 0; m_copyback(m, skip + offsetof(struct udphdr, uh_sum), sizeof(cksum), &cksum, M_NOWAIT); #ifdef INET6 if (af == AF_INET6) { cksum = in6_cksum(m, IPPROTO_UDP, skip, m->m_pkthdr.len - skip); m_copyback(m, skip + offsetof(struct udphdr, uh_sum), sizeof(cksum), &cksum, M_NOWAIT); } #endif break; case IPPROTO_TCP: if (m->m_pkthdr.len < skip + sizeof(struct tcphdr)) { IPSEC_ISTAT(esps_hdrops, ahs_hdrops, ipcomps_hdrops); goto baddone; } cksum = 0; m_copyback(m, skip + offsetof(struct tcphdr, th_sum), sizeof(cksum), &cksum, M_NOWAIT); if (af == AF_INET) cksum = in4_cksum(m, IPPROTO_TCP, skip, m->m_pkthdr.len - skip); #ifdef INET6 else if (af == AF_INET6) cksum = in6_cksum(m, IPPROTO_TCP, skip, m->m_pkthdr.len - skip); #endif m_copyback(m, skip + offsetof(struct tcphdr, th_sum), sizeof(cksum), &cksum, M_NOWAIT); break; } } /* * Record what we've done to the packet (under what SA it was * processed). */ if (tdbp->tdb_sproto != IPPROTO_IPCOMP) { mtag = m_tag_get(PACKET_TAG_IPSEC_IN_DONE, sizeof(struct tdb_ident), M_NOWAIT); if (mtag == NULL) { DPRINTF("failed to get tag"); IPSEC_ISTAT(esps_hdrops, ahs_hdrops, ipcomps_hdrops); goto baddone; } tdbi = (struct tdb_ident *)(mtag + 1); tdbi->dst = tdbp->tdb_dst; tdbi->proto = tdbp->tdb_sproto; tdbi->spi = tdbp->tdb_spi; tdbi->rdomain = tdbp->tdb_rdomain; m_tag_prepend(m, mtag); } switch (sproto) { case IPPROTO_ESP: /* Packet is confidential ? */ if (tdbp->tdb_encalgxform) m->m_flags |= M_CONF; /* Check if we had authenticated ESP. */ if (tdbp->tdb_authalgxform) m->m_flags |= M_AUTH; break; case IPPROTO_AH: m->m_flags |= M_AUTH; break; case IPPROTO_IPCOMP: m->m_flags |= M_COMP; break; default: panic("%s: unknown/unsupported security protocol %d", __func__, sproto); } #if NPF > 0 /* Add pf tag if requested. */ pf_tag_packet(m, tdbp->tdb_tag, -1); pf_pkt_addr_changed(m); #endif if (tdbp->tdb_rdomain != tdbp->tdb_rdomain_post) m->m_pkthdr.ph_rtableid = tdbp->tdb_rdomain_post; if (tdbp->tdb_flags & TDBF_TUNNELING) m->m_flags |= M_TUNNEL; ipsecstat_add(ipsec_idecompbytes, m->m_pkthdr.len); tdbstat_add(tdbp, tdb_idecompbytes, m->m_pkthdr.len); #if NBPFILTER > 0 encif = enc_getif(tdbp->tdb_rdomain_post, tdbp->tdb_tap); if (encif != NULL) { encif->if_ipackets++; encif->if_ibytes += m->m_pkthdr.len; if (sproto != IPPROTO_IPCOMP) { /* XXX This conflicts with the scoped nature of IPv6 */ m->m_pkthdr.ph_ifidx = encif->if_index; } if (encif->if_bpf) { struct enchdr hdr; hdr.af = af; hdr.spi = tdbp->tdb_spi; hdr.flags = m->m_flags & (M_AUTH|M_CONF); bpf_mtap_hdr(encif->if_bpf, (char *)&hdr, ENC_HDRLEN, m, BPF_DIRECTION_IN); } } #endif if (ISSET(tdbp->tdb_flags, TDBF_IFACE)) { #if NSEC > 0 if (ISSET(tdbp->tdb_flags, TDBF_TUNNELING) && tdbp->tdb_iface_dir == IPSP_DIRECTION_IN) { struct sec_softc *sc = sec_get(tdbp->tdb_iface); if (sc == NULL) goto baddone; sec_input(sc, af, prot, m, ns); sec_put(sc); return IPPROTO_DONE; } #endif /* NSEC > 0 */ goto baddone; } #if NPF > 0 /* * The ip_deliver() shortcut avoids running through ip_input() with the * same IP header twice. Packets in transport mode have to be be * passed to pf explicitly. In tunnel mode the inner IP header will * run through ip_input() and pf anyway. */ if ((tdbp->tdb_flags & TDBF_TUNNELING) == 0) { struct ifnet *ifp; /* This is the enc0 interface unless for ipcomp. */ if ((ifp = if_get(m->m_pkthdr.ph_ifidx)) == NULL) { goto baddone; } if (pf_test(af, PF_IN, ifp, mp) != PF_PASS) { if_put(ifp); goto baddone; } m = *mp; if_put(ifp); if (m == NULL) return IPPROTO_DONE; } #endif /* Return to the appropriate protocol handler in deliver loop. */ return prot; baddone: m_freemp(mp); return IPPROTO_DONE; #undef IPSEC_ISTAT } int ipsec_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp, size_t newlen) { switch (name[0]) { case IPCTL_IPSEC_ENC_ALGORITHM: case IPCTL_IPSEC_AUTH_ALGORITHM: case IPCTL_IPSEC_IPCOMP_ALGORITHM: return (ipsec_sysctl_algorithm(name[0], oldp, oldlenp, newp, newlen)); case IPCTL_IPSEC_STATS: return (ipsec_sysctl_ipsecstat(oldp, oldlenp, newp)); default: return (sysctl_bounded_arr(ipsecctl_vars, nitems(ipsecctl_vars), name, namelen, oldp, oldlenp, newp, newlen)); } } int ipsec_sysctl_algorithm(int name, void *oldp, size_t *oldlenp, void *newp, size_t newlen) { const struct ipsec_sysctl_algorithm *algs, *p; int *var, oldval, error; char buf[20]; switch (name) { case IPCTL_IPSEC_ENC_ALGORITHM: algs = ipsec_sysctl_enc_algs; var = &ipsec_def_enc; break; case IPCTL_IPSEC_AUTH_ALGORITHM: algs = ipsec_sysctl_auth_algs; var = &ipsec_def_auth; break; case IPCTL_IPSEC_IPCOMP_ALGORITHM: algs = ipsec_sysctl_comp_algs; var = &ipsec_def_comp; break; default: return (EOPNOTSUPP); } oldval = atomic_load_int(var); for (p = algs; p->name != NULL; p++) { if (p->val == oldval) { strlcpy(buf, p->name, sizeof(buf)); break; } } KASSERT(p->name != NULL); error = sysctl_tstring(oldp, oldlenp, newp, newlen, buf, sizeof(buf)); if (error) return (error); if (newp) { size_t buflen; if ((buflen = strlen(buf)) == 0) return (EINVAL); for (p = algs; p->name != NULL; p++) { if (strncasecmp(buf, p->name, buflen) == 0) break; } if (p->name == NULL) return (EINVAL); if (p->val != oldval) atomic_store_int(var, p->val); } return (0); } int esp_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp, size_t newlen) { /* All sysctl names at this level are terminal. */ if (namelen != 1) return (ENOTDIR); switch (name[0]) { case ESPCTL_STATS: return (esp_sysctl_espstat(oldp, oldlenp, newp)); default: return (sysctl_bounded_arr(espctl_vars, nitems(espctl_vars), name, namelen, oldp, oldlenp, newp, newlen)); } } int esp_sysctl_espstat(void *oldp, size_t *oldlenp, void *newp) { struct espstat espstat; CTASSERT(sizeof(espstat) == (esps_ncounters * sizeof(uint64_t))); memset(&espstat, 0, sizeof espstat); counters_read(espcounters, (uint64_t *)&espstat, esps_ncounters, NULL); return (sysctl_rdstruct(oldp, oldlenp, newp, &espstat, sizeof(espstat))); } int ah_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp, size_t newlen) { /* All sysctl names at this level are terminal. */ if (namelen != 1) return (ENOTDIR); switch (name[0]) { case AHCTL_STATS: return ah_sysctl_ahstat(oldp, oldlenp, newp); default: return sysctl_bounded_arr(ahctl_vars, nitems(ahctl_vars), name, namelen, oldp, oldlenp, newp, newlen); } } int ah_sysctl_ahstat(void *oldp, size_t *oldlenp, void *newp) { struct ahstat ahstat; CTASSERT(sizeof(ahstat) == (ahs_ncounters * sizeof(uint64_t))); memset(&ahstat, 0, sizeof ahstat); counters_read(ahcounters, (uint64_t *)&ahstat, ahs_ncounters, NULL); return (sysctl_rdstruct(oldp, oldlenp, newp, &ahstat, sizeof(ahstat))); } int ipcomp_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp, size_t newlen) { /* All sysctl names at this level are terminal. */ if (namelen != 1) return (ENOTDIR); switch (name[0]) { case IPCOMPCTL_STATS: return ipcomp_sysctl_ipcompstat(oldp, oldlenp, newp); default: return sysctl_bounded_arr(ipcompctl_vars, nitems(ipcompctl_vars), name, namelen, oldp, oldlenp, newp, newlen); } } int ipcomp_sysctl_ipcompstat(void *oldp, size_t *oldlenp, void *newp) { struct ipcompstat ipcompstat; CTASSERT(sizeof(ipcompstat) == (ipcomps_ncounters * sizeof(uint64_t))); memset(&ipcompstat, 0, sizeof ipcompstat); counters_read(ipcompcounters, (uint64_t *)&ipcompstat, ipcomps_ncounters, NULL); return (sysctl_rdstruct(oldp, oldlenp, newp, &ipcompstat, sizeof(ipcompstat))); } int ipsec_sysctl_ipsecstat(void *oldp, size_t *oldlenp, void *newp) { struct ipsecstat ipsecstat; CTASSERT(sizeof(ipsecstat) == (ipsec_ncounters * sizeof(uint64_t))); memset(&ipsecstat, 0, sizeof ipsecstat); counters_read(ipseccounters, (uint64_t *)&ipsecstat, ipsec_ncounters, NULL); return (sysctl_rdstruct(oldp, oldlenp, newp, &ipsecstat, sizeof(ipsecstat))); } int ipsec_input_disabled(struct mbuf **mp, int *offp, int proto, int af, struct netstack *ns) { switch (af) { case AF_INET: return rip_input(mp, offp, proto, af, ns); #ifdef INET6 case AF_INET6: return rip6_input(mp, offp, proto, af, ns); #endif default: unhandled_af(af); } } int ah46_input(struct mbuf **mp, int *offp, int proto, int af, struct netstack *ns) { int protoff; if ( #if NPF > 0 ((*mp)->m_pkthdr.pf.flags & PF_TAG_DIVERTED) || #endif !atomic_load_int(&ah_enable)) return ipsec_input_disabled(mp, offp, proto, af, ns); protoff = ipsec_protoff(*mp, *offp, af); if (protoff < 0) { DPRINTF("bad packet header chain"); ahstat_inc(ahs_hdrops); m_freemp(mp); return IPPROTO_DONE; } return ipsec_common_input(mp, *offp, protoff, af, proto, 0, ns); } void ah4_ctlinput(int cmd, struct sockaddr *sa, u_int rdomain, void *v) { if (sa->sa_family != AF_INET || sa->sa_len != sizeof(struct sockaddr_in)) return; ipsec_common_ctlinput(rdomain, cmd, sa, v, IPPROTO_AH); } int esp46_input(struct mbuf **mp, int *offp, int proto, int af, struct netstack *ns) { int protoff; if ( #if NPF > 0 ((*mp)->m_pkthdr.pf.flags & PF_TAG_DIVERTED) || #endif !atomic_load_int(&esp_enable)) return ipsec_input_disabled(mp, offp, proto, af, ns); protoff = ipsec_protoff(*mp, *offp, af); if (protoff < 0) { DPRINTF("bad packet header chain"); espstat_inc(esps_hdrops); m_freemp(mp); return IPPROTO_DONE; } return ipsec_common_input(mp, *offp, protoff, af, proto, 0, ns); } /* IPv4 IPCOMP wrapper */ int ipcomp46_input(struct mbuf **mp, int *offp, int proto, int af, struct netstack *ns) { int protoff; if ( #if NPF > 0 ((*mp)->m_pkthdr.pf.flags & PF_TAG_DIVERTED) || #endif !atomic_load_int(&ipcomp_enable)) return ipsec_input_disabled(mp, offp, proto, af, ns); protoff = ipsec_protoff(*mp, *offp, af); if (protoff < 0) { DPRINTF("bad packet header chain"); ipcompstat_inc(ipcomps_hdrops); m_freemp(mp); return IPPROTO_DONE; } return ipsec_common_input(mp, *offp, protoff, af, proto, 0, ns); } void ipsec_set_mtu(struct tdb *tdbp, u_int32_t mtu) { ssize_t adjust; NET_ASSERT_LOCKED(); /* Walk the chain backwards to the first tdb */ for (; tdbp != NULL; tdbp = tdbp->tdb_inext) { if (tdbp->tdb_flags & TDBF_INVALID || (adjust = ipsec_hdrsz(tdbp)) == -1) return; mtu -= adjust; /* Store adjusted MTU in tdb */ tdbp->tdb_mtu = mtu; tdbp->tdb_mtutimeout = gettime() + atomic_load_int(&ip_mtudisc_timeout); DPRINTF("spi %08x mtu %d adjust %ld", ntohl(tdbp->tdb_spi), tdbp->tdb_mtu, adjust); } } void ipsec_common_ctlinput(u_int rdomain, int cmd, struct sockaddr *sa, void *v, int proto) { struct ip *ip = v; if (cmd == PRC_MSGSIZE && ip && atomic_load_int(&ip_mtudisc) && ip->ip_v == 4) { struct tdb *tdbp; struct sockaddr_in dst; struct icmp *icp; int hlen = ip->ip_hl << 2; u_int32_t spi, mtu; /* Find the right MTU. */ icp = (struct icmp *)((caddr_t) ip - offsetof(struct icmp, icmp_ip)); mtu = ntohs(icp->icmp_nextmtu); /* * Ignore the packet, if we do not receive a MTU * or the MTU is too small to be acceptable. */ if (mtu < 296) return; memset(&dst, 0, sizeof(struct sockaddr_in)); dst.sin_family = AF_INET; dst.sin_len = sizeof(struct sockaddr_in); dst.sin_addr.s_addr = ip->ip_dst.s_addr; memcpy(&spi, (caddr_t)ip + hlen, sizeof(u_int32_t)); tdbp = gettdb_rev(rdomain, spi, (union sockaddr_union *)&dst, proto); ipsec_set_mtu(tdbp, mtu); tdb_unref(tdbp); } } void udpencap_ctlinput(int cmd, struct sockaddr *sa, u_int rdomain, void *v) { struct ip *ip = v; struct tdb *tdbp, *first; struct icmp *icp; u_int32_t mtu; struct sockaddr_in dst, src; union sockaddr_union *su_dst, *su_src; NET_ASSERT_LOCKED(); icp = (struct icmp *)((caddr_t) ip - offsetof(struct icmp, icmp_ip)); mtu = ntohs(icp->icmp_nextmtu); /* * Ignore the packet, if we do not receive a MTU * or the MTU is too small to be acceptable. */ if (mtu < 296) return; memset(&dst, 0, sizeof(dst)); dst.sin_family = AF_INET; dst.sin_len = sizeof(struct sockaddr_in); dst.sin_addr.s_addr = ip->ip_dst.s_addr; su_dst = (union sockaddr_union *)&dst; memset(&src, 0, sizeof(src)); src.sin_family = AF_INET; src.sin_len = sizeof(struct sockaddr_in); src.sin_addr.s_addr = ip->ip_src.s_addr; su_src = (union sockaddr_union *)&src; first = gettdbbysrcdst_rev(rdomain, 0, su_src, su_dst, IPPROTO_ESP); mtx_enter(&tdb_sadb_mtx); for (tdbp = first; tdbp != NULL; tdbp = tdbp->tdb_snext) { if (tdbp->tdb_sproto == IPPROTO_ESP && ((tdbp->tdb_flags & (TDBF_INVALID|TDBF_UDPENCAP)) == TDBF_UDPENCAP) && !memcmp(&tdbp->tdb_dst, &dst, su_dst->sa.sa_len) && !memcmp(&tdbp->tdb_src, &src, su_src->sa.sa_len)) ipsec_set_mtu(tdbp, mtu); } mtx_leave(&tdb_sadb_mtx); tdb_unref(first); } void esp4_ctlinput(int cmd, struct sockaddr *sa, u_int rdomain, void *v) { if (sa->sa_family != AF_INET || sa->sa_len != sizeof(struct sockaddr_in)) return; ipsec_common_ctlinput(rdomain, cmd, sa, v, IPPROTO_ESP); } /* Find the offset of the next protocol field in the previous header. */ int ipsec_protoff(struct mbuf *m, int off, int af) { #ifdef INET6 struct ip6_ext ip6e; int protoff, nxt, l; #endif /* INET6 */ switch (af) { case AF_INET: return offsetof(struct ip, ip_p); #ifdef INET6 case AF_INET6: break; #endif /* INET6 */ default: unhandled_af(af); } #ifdef INET6 if (off < sizeof(struct ip6_hdr)) return -1; if (off == sizeof(struct ip6_hdr)) return offsetof(struct ip6_hdr, ip6_nxt); /* Chase down the header chain... */ protoff = sizeof(struct ip6_hdr); nxt = (mtod(m, struct ip6_hdr *))->ip6_nxt; l = 0; do { protoff += l; m_copydata(m, protoff, sizeof(ip6e), (caddr_t) &ip6e); if (nxt == IPPROTO_AH) l = (ip6e.ip6e_len + 2) << 2; else l = (ip6e.ip6e_len + 1) << 3; #ifdef DIAGNOSTIC if (l <= 0) panic("%s: l went zero or negative", __func__); #endif nxt = ip6e.ip6e_nxt; } while (protoff + l < off); /* Malformed packet check */ if (protoff + l != off) return -1; protoff += offsetof(struct ip6_ext, ip6e_nxt); return protoff; #endif /* INET6 */ } int ipsec_forward_check(struct mbuf *m, int hlen, int af) { struct tdb *tdb; struct tdb_ident *tdbi; struct m_tag *mtag; int error = 0; /* * IPsec policy check for forwarded packets. Look at * inner-most IPsec SA used. */ mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); if (mtag != NULL) { tdbi = (struct tdb_ident *)(mtag + 1); tdb = gettdb(tdbi->rdomain, tdbi->spi, &tdbi->dst, tdbi->proto); } else tdb = NULL; error = ipsp_spd_lookup(m, af, hlen, IPSP_DIRECTION_IN, tdb, NULL, NULL, NULL); tdb_unref(tdb); return error; } int ipsec_local_check(struct mbuf *m, int hlen, int proto, int af) { struct tdb *tdb; struct tdb_ident *tdbi; struct m_tag *mtag; int error = 0; /* * If it's a protected packet for us, skip the policy check. * That's because we really only care about the properties of * the protected packet, and not the intermediate versions. * While this is not the most paranoid setting, it allows * some flexibility in handling nested tunnels (in setting up * the policies). */ if ((proto == IPPROTO_ESP) || (proto == IPPROTO_AH) || (proto == IPPROTO_IPCOMP)) return 0; /* * If the protected packet was tunneled, then we need to * verify the protected packet's information, not the * external headers. Thus, skip the policy lookup for the * external packet, and keep the IPsec information linked on * the packet header (the encapsulation routines know how * to deal with that). */ if ((proto == IPPROTO_IPV4) || (proto == IPPROTO_IPV6)) return 0; /* * When processing IPv6 header chains, do not look at the * outer header. The inner protocol is relevant and will * be checked by the local delivery loop later. */ if ((af == AF_INET6) && ((proto == IPPROTO_DSTOPTS) || (proto == IPPROTO_ROUTING) || (proto == IPPROTO_FRAGMENT))) return 0; /* * If the protected packet is TCP or UDP, we'll do the * policy check in the respective input routine, so we can * check for bypass sockets. */ if ((proto == IPPROTO_TCP) || (proto == IPPROTO_UDP)) return 0; /* * IPsec policy check for local-delivery packets. Look at the * inner-most SA that protected the packet. This is in fact * a bit too restrictive (it could end up causing packets to * be dropped that semantically follow the policy, e.g., in * certain SA-bundle configurations); but the alternative is * very complicated (and requires keeping track of what * kinds of tunneling headers have been seen in-between the * IPsec headers), and I don't think we lose much functionality * that's needed in the real world (who uses bundles anyway ?). */ mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); if (mtag) { tdbi = (struct tdb_ident *)(mtag + 1); tdb = gettdb(tdbi->rdomain, tdbi->spi, &tdbi->dst, tdbi->proto); } else tdb = NULL; error = ipsp_spd_lookup(m, af, hlen, IPSP_DIRECTION_IN, tdb, NULL, NULL, NULL); tdb_unref(tdb); return error; }