/* $FreeBSD$ */ /* $KAME: ipsec.c,v 1.103 2001/05/24 07:14:18 sakane 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. */ /* * IPsec controller part. */ #include "opt_inet.h" #include "opt_inet6.h" #include "opt_ipsec.h" #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 #include #include #include #ifdef INET6 #include #endif #include #ifdef INET6 #include #endif #include #include #ifdef INET6 #include #endif #include #include #include /*XXX*/ #include #include #include #include #include #include #include #ifndef VIMAGE #ifndef VIMAGE_GLOBALS struct vnet_ipsec vnet_ipsec_0; #endif #endif static int ipsec_iattach(const void *); #ifdef VIMAGE_GLOBALS /* NB: name changed so netstat doesn't use it. */ struct ipsecstat ipsec4stat; struct secpolicy ip4_def_policy; int ipsec_debug; int ip4_ah_offsetmask; int ip4_ipsec_dfbit; int ip4_esp_trans_deflev; int ip4_esp_net_deflev; int ip4_ah_trans_deflev; int ip4_ah_net_deflev; int ip4_ipsec_ecn; int ip4_esp_randpad; /* * Crypto support requirements: * * 1 require hardware support * -1 require software support * 0 take anything */ int crypto_support; #endif /* VIMAGE_GLOBALS */ SYSCTL_DECL(_net_inet_ipsec); /* net.inet.ipsec */ SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy, CTLFLAG_RW, ip4_def_policy.policy, 0, "IPsec default policy."); SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev, CTLFLAG_RW, ip4_esp_trans_deflev, 0, "Default ESP transport mode level"); SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev, CTLFLAG_RW, ip4_esp_net_deflev, 0, "Default ESP tunnel mode level."); SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev, CTLFLAG_RW, ip4_ah_trans_deflev, 0, "AH transfer mode default level."); SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev, CTLFLAG_RW, ip4_ah_net_deflev, 0, "AH tunnel mode default level."); SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos, CTLFLAG_RW, ah_cleartos, 0, "If set clear type-of-service field when doing AH computation."); SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, ah_offsetmask, CTLFLAG_RW, ip4_ah_offsetmask, 0, "If not set clear offset field mask when doing AH computation."); SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DFBIT, dfbit, CTLFLAG_RW, ip4_ipsec_dfbit, 0, "Do not fragment bit on encap."); SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_ECN, ecn, CTLFLAG_RW, ip4_ipsec_ecn, 0, "Explicit Congestion Notification handling."); SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEBUG, debug, CTLFLAG_RW, ipsec_debug, 0, "Enable IPsec debugging output when set."); SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, OID_AUTO, crypto_support, CTLFLAG_RW, crypto_support,0, "Crypto driver selection."); SYSCTL_V_STRUCT(V_NET, vnet_ipsec, _net_inet_ipsec, OID_AUTO, ipsecstats, CTLFLAG_RD, ipsec4stat, ipsecstat, "IPsec IPv4 statistics."); #ifdef REGRESSION #ifdef VIMAGE_GLOBALS int ipsec_replay; int ipsec_integrity; #endif /* * When set to 1, IPsec will send packets with the same sequence number. * This allows to verify if the other side has proper replay attacks detection. */ SYSCTL_V_INT(V_NET, vnet_ipsec,_net_inet_ipsec, OID_AUTO, test_replay, CTLFLAG_RW, ipsec_replay, 0, "Emulate replay attack"); /* * When set 1, IPsec will send packets with corrupted HMAC. * This allows to verify if the other side properly detects modified packets. */ SYSCTL_V_INT(V_NET, vnet_ipsec,_net_inet_ipsec, OID_AUTO, test_integrity, CTLFLAG_RW, ipsec_integrity, 0, "Emulate man-in-the-middle attack"); #endif #ifdef INET6 #ifdef VIMAGE_GLOBALS struct ipsecstat ipsec6stat; int ip6_esp_trans_deflev; int ip6_esp_net_deflev; int ip6_ah_trans_deflev; int ip6_ah_net_deflev; int ip6_ipsec_ecn; #endif SYSCTL_DECL(_net_inet6_ipsec6); /* net.inet6.ipsec6 */ #ifdef COMPAT_KAME SYSCTL_OID(_net_inet6_ipsec6, IPSECCTL_STATS, stats, CTLFLAG_RD, 0, 0, compat_ipsecstats_sysctl, "S", "IPsec IPv6 statistics."); #endif /* COMPAT_KAME */ SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy, CTLFLAG_RW, ip4_def_policy.policy, 0, "IPsec default policy."); SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev, CTLFLAG_RW, ip6_esp_trans_deflev, 0, "Default ESP transport mode level."); SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev, CTLFLAG_RW, ip6_esp_net_deflev, 0, "Default ESP tunnel mode level."); SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev, CTLFLAG_RW, ip6_ah_trans_deflev, 0, "AH transfer mode default level."); SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev, CTLFLAG_RW, ip6_ah_net_deflev, 0, "AH tunnel mode default level."); SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_ECN, ecn, CTLFLAG_RW, ip6_ipsec_ecn, 0, "Explicit Congestion Notification handling."); SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEBUG, debug, CTLFLAG_RW, ipsec_debug, 0, "Enable IPsec debugging output when set."); SYSCTL_V_STRUCT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_STATS, ipsecstats, CTLFLAG_RD, ipsec6stat, ipsecstat, "IPsec IPv6 statistics."); #endif /* INET6 */ static int ipsec_setspidx_inpcb __P((struct mbuf *, struct inpcb *)); static int ipsec_setspidx __P((struct mbuf *, struct secpolicyindex *, int)); static void ipsec4_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); static int ipsec4_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); #ifdef INET6 static void ipsec6_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); static int ipsec6_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); #endif static void ipsec_delpcbpolicy __P((struct inpcbpolicy *)); static struct secpolicy *ipsec_deepcopy_policy __P((struct secpolicy *src)); static void vshiftl __P((unsigned char *, int, int)); MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy"); #ifndef VIMAGE_GLOBALS static const vnet_modinfo_t vnet_ipsec_modinfo = { .vmi_id = VNET_MOD_IPSEC, .vmi_name = "ipsec", .vmi_dependson = VNET_MOD_INET, /* XXX revisit - INET6 ? */ .vmi_iattach = ipsec_iattach }; #endif /* !VIMAGE_GLOBALS */ void ipsec_init(void) { INIT_VNET_IPSEC(curvnet); #ifdef IPSEC_DEBUG V_ipsec_debug = 1; #else V_ipsec_debug = 0; #endif V_ip4_ah_offsetmask = 0; /* maybe IP_DF? */ V_ip4_ipsec_dfbit = 0; /* DF bit on encap. 0: clear 1: set 2: copy */ V_ip4_esp_trans_deflev = IPSEC_LEVEL_USE; V_ip4_esp_net_deflev = IPSEC_LEVEL_USE; V_ip4_ah_trans_deflev = IPSEC_LEVEL_USE; V_ip4_ah_net_deflev = IPSEC_LEVEL_USE; V_ip4_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ V_ip4_esp_randpad = -1; V_crypto_support = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE; #ifdef REGRESSION V_ipsec_replay = 0; V_ipsec_integrity = 0; #endif #ifdef INET6 V_ip6_esp_trans_deflev = IPSEC_LEVEL_USE; V_ip6_esp_net_deflev = IPSEC_LEVEL_USE; V_ip6_ah_trans_deflev = IPSEC_LEVEL_USE; V_ip6_ah_net_deflev = IPSEC_LEVEL_USE; V_ip6_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ #endif } /* * Return a held reference to the default SP. */ static struct secpolicy * key_allocsp_default(const char* where, int tag) { INIT_VNET_IPSEC(curvnet); struct secpolicy *sp; KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP key_allocsp_default from %s:%u\n", where, tag)); sp = &V_ip4_def_policy; if (sp->policy != IPSEC_POLICY_DISCARD && sp->policy != IPSEC_POLICY_NONE) { ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n", sp->policy, IPSEC_POLICY_NONE)); sp->policy = IPSEC_POLICY_NONE; } key_addref(sp); KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP key_allocsp_default returns SP:%p (%u)\n", sp, sp->refcnt)); return (sp); } #define KEY_ALLOCSP_DEFAULT() \ key_allocsp_default(__FILE__, __LINE__) /* * For OUTBOUND packet having a socket. Searching SPD for packet, * and return a pointer to SP. * OUT: NULL: no apropreate SP found, the following value is set to error. * 0 : bypass * EACCES : discard packet. * ENOENT : ipsec_acquire() in progress, maybe. * others : error occured. * others: a pointer to SP * * NOTE: IPv6 mapped adddress concern is implemented here. */ struct secpolicy * ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir) { struct secpolicy *sp; IPSEC_ASSERT(tdbi != NULL, ("null tdbi")); IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, ("invalid direction %u", dir)); sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir); if (sp == NULL) /*XXX????*/ sp = KEY_ALLOCSP_DEFAULT(); IPSEC_ASSERT(sp != NULL, ("null SP")); return (sp); } /* * For OUTBOUND packet having a socket. Searching SPD for packet, * and return a pointer to SP. * OUT: NULL: no apropreate SP found, the following value is set to error. * 0 : bypass * EACCES : discard packet. * ENOENT : ipsec_acquire() in progress, maybe. * others : error occured. * others: a pointer to SP * * NOTE: IPv6 mapped adddress concern is implemented here. */ static struct secpolicy * ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb *inp, int *error) { INIT_VNET_IPSEC(curvnet); struct inpcbpolicy *pcbsp; struct secpolicy *currsp = NULL; /* Policy on socket. */ struct secpolicy *sp; IPSEC_ASSERT(m != NULL, ("null mbuf")); IPSEC_ASSERT(inp != NULL, ("null inpcb")); IPSEC_ASSERT(error != NULL, ("null error")); IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, ("invalid direction %u", dir)); /* Set spidx in pcb. */ *error = ipsec_setspidx_inpcb(m, inp); if (*error) return (NULL); pcbsp = inp->inp_sp; IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp")); switch (dir) { case IPSEC_DIR_INBOUND: currsp = pcbsp->sp_in; break; case IPSEC_DIR_OUTBOUND: currsp = pcbsp->sp_out; break; } IPSEC_ASSERT(currsp != NULL, ("null currsp")); if (pcbsp->priv) { /* When privilieged socket. */ switch (currsp->policy) { case IPSEC_POLICY_BYPASS: case IPSEC_POLICY_IPSEC: key_addref(currsp); sp = currsp; break; case IPSEC_POLICY_ENTRUST: /* Look for a policy in SPD. */ sp = KEY_ALLOCSP(&currsp->spidx, dir); if (sp == NULL) /* No SP found. */ sp = KEY_ALLOCSP_DEFAULT(); break; default: ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n", __func__, currsp->policy)); *error = EINVAL; return (NULL); } } else { /* Unpriv, SPD has policy. */ sp = KEY_ALLOCSP(&currsp->spidx, dir); if (sp == NULL) { /* No SP found. */ switch (currsp->policy) { case IPSEC_POLICY_BYPASS: ipseclog((LOG_ERR, "%s: Illegal policy for " "non-priviliged defined %d\n", __func__, currsp->policy)); *error = EINVAL; return (NULL); case IPSEC_POLICY_ENTRUST: sp = KEY_ALLOCSP_DEFAULT(); break; case IPSEC_POLICY_IPSEC: key_addref(currsp); sp = currsp; break; default: ipseclog((LOG_ERR, "%s: Invalid policy for " "PCB %d\n", __func__, currsp->policy)); *error = EINVAL; return (NULL); } } } IPSEC_ASSERT(sp != NULL, ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy)); KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n", __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt)); return (sp); } /* * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, * and return a pointer to SP. * OUT: positive: a pointer to the entry for security policy leaf matched. * NULL: no apropreate SP found, the following value is set to error. * 0 : bypass * EACCES : discard packet. * ENOENT : ipsec_acquire() in progress, maybe. * others : error occured. */ struct secpolicy * ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) { INIT_VNET_IPSEC(curvnet); struct secpolicyindex spidx; struct secpolicy *sp; IPSEC_ASSERT(m != NULL, ("null mbuf")); IPSEC_ASSERT(error != NULL, ("null error")); IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, ("invalid direction %u", dir)); sp = NULL; if (key_havesp(dir)) { /* Make an index to look for a policy. */ *error = ipsec_setspidx(m, &spidx, (flag & IP_FORWARDING) ? 0 : 1); if (*error != 0) { DPRINTF(("%s: setpidx failed, dir %u flag %u\n", __func__, dir, flag)); return (NULL); } spidx.dir = dir; sp = KEY_ALLOCSP(&spidx, dir); } if (sp == NULL) /* No SP found, use system default. */ sp = KEY_ALLOCSP_DEFAULT(); IPSEC_ASSERT(sp != NULL, ("null SP")); return (sp); } struct secpolicy * ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, struct inpcb *inp) { INIT_VNET_IPSEC(curvnet); struct secpolicy *sp; *error = 0; if (inp == NULL) sp = ipsec_getpolicybyaddr(m, dir, flag, error); else sp = ipsec_getpolicybysock(m, dir, inp, error); if (sp == NULL) { IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error")); V_ipsec4stat.ips_out_inval++; return (NULL); } IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error)); switch (sp->policy) { case IPSEC_POLICY_ENTRUST: default: printf("%s: invalid policy %u\n", __func__, sp->policy); /* FALLTHROUGH */ case IPSEC_POLICY_DISCARD: V_ipsec4stat.ips_out_polvio++; *error = -EINVAL; /* Packet is discarded by caller. */ break; case IPSEC_POLICY_BYPASS: case IPSEC_POLICY_NONE: KEY_FREESP(&sp); sp = NULL; /* NB: force NULL result. */ break; case IPSEC_POLICY_IPSEC: if (sp->req == NULL) /* Acquire a SA. */ *error = key_spdacquire(sp); break; } if (*error != 0) { KEY_FREESP(&sp); sp = NULL; } return (sp); } static int ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp) { int error; IPSEC_ASSERT(inp != NULL, ("null inp")); IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL, ("null sp_in || sp_out")); error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1); if (error == 0) { inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx; inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; } else { bzero(&inp->inp_sp->sp_in->spidx, sizeof (inp->inp_sp->sp_in->spidx)); bzero(&inp->inp_sp->sp_out->spidx, sizeof (inp->inp_sp->sp_in->spidx)); } return (error); } /* * Configure security policy index (src/dst/proto/sport/dport) * by looking at the content of mbuf. * The caller is responsible for error recovery (like clearing up spidx). */ static int ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) { INIT_VNET_IPSEC(curvnet); struct ip *ip = NULL; struct ip ipbuf; u_int v; struct mbuf *n; int len; int error; IPSEC_ASSERT(m != NULL, ("null mbuf")); /* * Validate m->m_pkthdr.len. We see incorrect length if we * mistakenly call this function with inconsistent mbuf chain * (like 4.4BSD tcp/udp processing). XXX Should we panic here? */ len = 0; for (n = m; n; n = n->m_next) len += n->m_len; if (m->m_pkthdr.len != len) { KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n", __func__, len, m->m_pkthdr.len)); return (EINVAL); } if (m->m_pkthdr.len < sizeof(struct ip)) { KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s: pkthdr len(%d) too small (v4), ignored.\n", __func__, m->m_pkthdr.len)); return (EINVAL); } if (m->m_len >= sizeof(*ip)) ip = mtod(m, struct ip *); else { m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf); ip = &ipbuf; } #ifdef _IP_VHL v = _IP_VHL_V(ip->ip_vhl); #else v = ip->ip_v; #endif switch (v) { case 4: error = ipsec4_setspidx_ipaddr(m, spidx); if (error) return (error); ipsec4_get_ulp(m, spidx, needport); return (0); #ifdef INET6 case 6: if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s: pkthdr len(%d) too small (v6), " "ignored\n", __func__, m->m_pkthdr.len)); return (EINVAL); } error = ipsec6_setspidx_ipaddr(m, spidx); if (error) return (error); ipsec6_get_ulp(m, spidx, needport); return (0); #endif default: KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s: " "unknown IP version %u, ignored.\n", __func__, v)); return (EINVAL); } } static void ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) { u_int8_t nxt; int off; /* Sanity check. */ IPSEC_ASSERT(m != NULL, ("null mbuf")); IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short")); /* NB: ip_input() flips it into host endian. XXX Need more checking. */ if (m->m_len < sizeof (struct ip)) { struct ip *ip = mtod(m, struct ip *); if (ip->ip_off & (IP_MF | IP_OFFMASK)) goto done; #ifdef _IP_VHL off = _IP_VHL_HL(ip->ip_vhl) << 2; #else off = ip->ip_hl << 2; #endif nxt = ip->ip_p; } else { struct ip ih; m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih); if (ih.ip_off & (IP_MF | IP_OFFMASK)) goto done; #ifdef _IP_VHL off = _IP_VHL_HL(ih.ip_vhl) << 2; #else off = ih.ip_hl << 2; #endif nxt = ih.ip_p; } while (off < m->m_pkthdr.len) { struct ip6_ext ip6e; struct tcphdr th; struct udphdr uh; switch (nxt) { case IPPROTO_TCP: spidx->ul_proto = nxt; if (!needport) goto done_proto; if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) goto done; m_copydata(m, off, sizeof (th), (caddr_t) &th); spidx->src.sin.sin_port = th.th_sport; spidx->dst.sin.sin_port = th.th_dport; return; case IPPROTO_UDP: spidx->ul_proto = nxt; if (!needport) goto done_proto; if (off + sizeof(struct udphdr) > m->m_pkthdr.len) goto done; m_copydata(m, off, sizeof (uh), (caddr_t) &uh); spidx->src.sin.sin_port = uh.uh_sport; spidx->dst.sin.sin_port = uh.uh_dport; return; case IPPROTO_AH: if (off + sizeof(ip6e) > m->m_pkthdr.len) goto done; /* XXX Sigh, this works but is totally bogus. */ m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e); off += (ip6e.ip6e_len + 2) << 2; nxt = ip6e.ip6e_nxt; break; case IPPROTO_ICMP: default: /* XXX Intermediate headers??? */ spidx->ul_proto = nxt; goto done_proto; } } done: spidx->ul_proto = IPSEC_ULPROTO_ANY; done_proto: spidx->src.sin.sin_port = IPSEC_PORT_ANY; spidx->dst.sin.sin_port = IPSEC_PORT_ANY; } /* Assumes that m is sane. */ static int ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) { static const struct sockaddr_in template = { sizeof (struct sockaddr_in), AF_INET, 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } }; spidx->src.sin = template; spidx->dst.sin = template; if (m->m_len < sizeof (struct ip)) { m_copydata(m, offsetof(struct ip, ip_src), sizeof (struct in_addr), (caddr_t) &spidx->src.sin.sin_addr); m_copydata(m, offsetof(struct ip, ip_dst), sizeof (struct in_addr), (caddr_t) &spidx->dst.sin.sin_addr); } else { struct ip *ip = mtod(m, struct ip *); spidx->src.sin.sin_addr = ip->ip_src; spidx->dst.sin.sin_addr = ip->ip_dst; } spidx->prefs = sizeof(struct in_addr) << 3; spidx->prefd = sizeof(struct in_addr) << 3; return (0); } #ifdef INET6 static void ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) { INIT_VNET_IPSEC(curvnet); int off, nxt; struct tcphdr th; struct udphdr uh; struct icmp6_hdr ih; /* Sanity check. */ if (m == NULL) panic("%s: NULL pointer was passed.\n", __func__); KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s:\n", __func__); kdebug_mbuf(m)); /* Set default. */ spidx->ul_proto = IPSEC_ULPROTO_ANY; ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; nxt = -1; off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); if (off < 0 || m->m_pkthdr.len < off) return; switch (nxt) { case IPPROTO_TCP: spidx->ul_proto = nxt; if (!needport) break; if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) break; m_copydata(m, off, sizeof(th), (caddr_t)&th); ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; break; case IPPROTO_UDP: spidx->ul_proto = nxt; if (!needport) break; if (off + sizeof(struct udphdr) > m->m_pkthdr.len) break; m_copydata(m, off, sizeof(uh), (caddr_t)&uh); ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; break; case IPPROTO_ICMPV6: spidx->ul_proto = nxt; if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) break; m_copydata(m, off, sizeof(ih), (caddr_t)&ih); ((struct sockaddr_in6 *)&spidx->src)->sin6_port = htons((uint16_t)ih.icmp6_type); ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = htons((uint16_t)ih.icmp6_code); break; default: /* XXX Intermediate headers??? */ spidx->ul_proto = nxt; break; } } /* Assumes that m is sane. */ static int ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) { struct ip6_hdr *ip6 = NULL; struct ip6_hdr ip6buf; struct sockaddr_in6 *sin6; if (m->m_len >= sizeof(*ip6)) ip6 = mtod(m, struct ip6_hdr *); else { m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf); ip6 = &ip6buf; } sin6 = (struct sockaddr_in6 *)&spidx->src; bzero(sin6, sizeof(*sin6)); sin6->sin6_family = AF_INET6; sin6->sin6_len = sizeof(struct sockaddr_in6); bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src)); if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { sin6->sin6_addr.s6_addr16[1] = 0; sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); } spidx->prefs = sizeof(struct in6_addr) << 3; sin6 = (struct sockaddr_in6 *)&spidx->dst; bzero(sin6, sizeof(*sin6)); sin6->sin6_family = AF_INET6; sin6->sin6_len = sizeof(struct sockaddr_in6); bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst)); if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { sin6->sin6_addr.s6_addr16[1] = 0; sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); } spidx->prefd = sizeof(struct in6_addr) << 3; return (0); } #endif static void ipsec_delpcbpolicy(struct inpcbpolicy *p) { free(p, M_IPSEC_INPCB); } /* Initialize policy in PCB. */ int ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp) { INIT_VNET_IPSEC(curvnet); struct inpcbpolicy *new; /* Sanity check. */ if (so == NULL || pcb_sp == NULL) panic("%s: NULL pointer was passed.\n", __func__); new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy), M_IPSEC_INPCB, M_NOWAIT|M_ZERO); if (new == NULL) { ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); return (ENOBUFS); } new->priv = IPSEC_IS_PRIVILEGED_SO(so); if ((new->sp_in = KEY_NEWSP()) == NULL) { ipsec_delpcbpolicy(new); return (ENOBUFS); } new->sp_in->state = IPSEC_SPSTATE_ALIVE; new->sp_in->policy = IPSEC_POLICY_ENTRUST; if ((new->sp_out = KEY_NEWSP()) == NULL) { KEY_FREESP(&new->sp_in); ipsec_delpcbpolicy(new); return (ENOBUFS); } new->sp_out->state = IPSEC_SPSTATE_ALIVE; new->sp_out->policy = IPSEC_POLICY_ENTRUST; *pcb_sp = new; return (0); } /* Copy old IPsec policy into new. */ int ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new) { struct secpolicy *sp; sp = ipsec_deepcopy_policy(old->sp_in); if (sp) { KEY_FREESP(&new->sp_in); new->sp_in = sp; } else return (ENOBUFS); sp = ipsec_deepcopy_policy(old->sp_out); if (sp) { KEY_FREESP(&new->sp_out); new->sp_out = sp; } else return (ENOBUFS); new->priv = old->priv; return (0); } struct ipsecrequest * ipsec_newisr(void) { struct ipsecrequest *p; p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO); if (p != NULL) IPSECREQUEST_LOCK_INIT(p); return (p); } void ipsec_delisr(struct ipsecrequest *p) { IPSECREQUEST_LOCK_DESTROY(p); free(p, M_IPSEC_SR); } /* Deep-copy a policy in PCB. */ static struct secpolicy * ipsec_deepcopy_policy(struct secpolicy *src) { struct ipsecrequest *newchain = NULL; struct ipsecrequest *p; struct ipsecrequest **q; struct ipsecrequest *r; struct secpolicy *dst; if (src == NULL) return (NULL); dst = KEY_NEWSP(); if (dst == NULL) return (NULL); /* * Deep-copy IPsec request chain. This is required since struct * ipsecrequest is not reference counted. */ q = &newchain; for (p = src->req; p; p = p->next) { *q = ipsec_newisr(); if (*q == NULL) goto fail; (*q)->saidx.proto = p->saidx.proto; (*q)->saidx.mode = p->saidx.mode; (*q)->level = p->level; (*q)->saidx.reqid = p->saidx.reqid; bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src)); bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst)); (*q)->sp = dst; q = &((*q)->next); } dst->req = newchain; dst->state = src->state; dst->policy = src->policy; /* Do not touch the refcnt fields. */ return (dst); fail: for (p = newchain; p; p = r) { r = p->next; ipsec_delisr(p); p = NULL; } return (NULL); } /* Set policy and IPsec request if present. */ static int ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname, caddr_t request, size_t len, struct ucred *cred) { INIT_VNET_IPSEC(curvnet); struct sadb_x_policy *xpl; struct secpolicy *newsp = NULL; int error; /* Sanity check. */ if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL) return (EINVAL); if (len < sizeof(*xpl)) return (EINVAL); xpl = (struct sadb_x_policy *)request; KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s: passed policy\n", __func__); kdebug_sadb_x_policy((struct sadb_ext *)xpl)); /* Check policy type. */ /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */ if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) return (EINVAL); /* Check privileged socket. */ if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0); if (error) return (EACCES); } /* Allocating new SP entry. */ if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) return (error); newsp->state = IPSEC_SPSTATE_ALIVE; /* Clear old SP and set new SP. */ KEY_FREESP(pcb_sp); *pcb_sp = newsp; KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s: new policy\n", __func__); kdebug_secpolicy(newsp)); return (0); } int ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request, size_t len, struct ucred *cred) { INIT_VNET_IPSEC(curvnet); struct sadb_x_policy *xpl; struct secpolicy **pcb_sp; /* Sanity check. */ if (inp == NULL || request == NULL) return (EINVAL); if (len < sizeof(*xpl)) return (EINVAL); xpl = (struct sadb_x_policy *)request; /* Select direction. */ switch (xpl->sadb_x_policy_dir) { case IPSEC_DIR_INBOUND: pcb_sp = &inp->inp_sp->sp_in; break; case IPSEC_DIR_OUTBOUND: pcb_sp = &inp->inp_sp->sp_out; break; default: ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, xpl->sadb_x_policy_dir)); return (EINVAL); } return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred)); } int ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len, struct mbuf **mp) { INIT_VNET_IPSEC(curvnet); struct sadb_x_policy *xpl; struct secpolicy *pcb_sp; /* Sanity check. */ if (inp == NULL || request == NULL || mp == NULL) return (EINVAL); IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); if (len < sizeof(*xpl)) return (EINVAL); xpl = (struct sadb_x_policy *)request; /* Select direction. */ switch (xpl->sadb_x_policy_dir) { case IPSEC_DIR_INBOUND: pcb_sp = inp->inp_sp->sp_in; break; case IPSEC_DIR_OUTBOUND: pcb_sp = inp->inp_sp->sp_out; break; default: ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, xpl->sadb_x_policy_dir)); return (EINVAL); } /* Sanity check. Should be an IPSEC_ASSERT. */ if (pcb_sp == NULL) return (EINVAL); *mp = key_sp2msg(pcb_sp); if (!*mp) { ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); return (ENOBUFS); } (*mp)->m_type = MT_DATA; KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s:\n", __func__); kdebug_mbuf(*mp)); return (0); } /* Delete policy in PCB. */ int ipsec_delete_pcbpolicy(struct inpcb *inp) { IPSEC_ASSERT(inp != NULL, ("null inp")); if (inp->inp_sp == NULL) return (0); if (inp->inp_sp->sp_in != NULL) KEY_FREESP(&inp->inp_sp->sp_in); if (inp->inp_sp->sp_out != NULL) KEY_FREESP(&inp->inp_sp->sp_out); ipsec_delpcbpolicy(inp->inp_sp); inp->inp_sp = NULL; return (0); } /* * Return current level. * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. */ u_int ipsec_get_reqlevel(struct ipsecrequest *isr) { INIT_VNET_IPSEC(curvnet); u_int level = 0; u_int esp_trans_deflev, esp_net_deflev; u_int ah_trans_deflev, ah_net_deflev; IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument")); IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, ("af family mismatch, src %u, dst %u", isr->sp->spidx.src.sa.sa_family, isr->sp->spidx.dst.sa.sa_family)); /* XXX Note that we have ipseclog() expanded here - code sync issue. */ #define IPSEC_CHECK_DEFAULT(lev) \ (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ && (lev) != IPSEC_LEVEL_UNIQUE) \ ? (V_ipsec_debug \ ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\ (lev), IPSEC_LEVEL_REQUIRE) \ : 0), \ (lev) = IPSEC_LEVEL_REQUIRE, \ (lev) \ : (lev)) /* Set default level. */ switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { #ifdef INET case AF_INET: esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev); esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev); ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev); ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev); break; #endif #ifdef INET6 case AF_INET6: esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev); esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev); ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev); ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev); break; #endif /* INET6 */ default: panic("%s: unknown af %u", __func__, isr->sp->spidx.src.sa.sa_family); } #undef IPSEC_CHECK_DEFAULT /* Set level. */ switch (isr->level) { case IPSEC_LEVEL_DEFAULT: switch (isr->saidx.proto) { case IPPROTO_ESP: if (isr->saidx.mode == IPSEC_MODE_TUNNEL) level = esp_net_deflev; else level = esp_trans_deflev; break; case IPPROTO_AH: if (isr->saidx.mode == IPSEC_MODE_TUNNEL) level = ah_net_deflev; else level = ah_trans_deflev; break; case IPPROTO_IPCOMP: /* * We don't really care, as IPcomp document says that * we shouldn't compress small packets. */ level = IPSEC_LEVEL_USE; break; default: panic("%s: Illegal protocol defined %u\n", __func__, isr->saidx.proto); } break; case IPSEC_LEVEL_USE: case IPSEC_LEVEL_REQUIRE: level = isr->level; break; case IPSEC_LEVEL_UNIQUE: level = IPSEC_LEVEL_REQUIRE; break; default: panic("%s: Illegal IPsec level %u\n", __func__, isr->level); } return (level); } /* * Check security policy requirements against the actual * packet contents. Return one if the packet should be * reject as "invalid"; otherwiser return zero to have the * packet treated as "valid". * * OUT: * 0: valid * 1: invalid */ int ipsec_in_reject(struct secpolicy *sp, struct mbuf *m) { INIT_VNET_IPSEC(curvnet); struct ipsecrequest *isr; int need_auth; KEYDEBUG(KEYDEBUG_IPSEC_DATA, printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); /* Check policy. */ switch (sp->policy) { case IPSEC_POLICY_DISCARD: return (1); case IPSEC_POLICY_BYPASS: case IPSEC_POLICY_NONE: return (0); } IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, ("invalid policy %u", sp->policy)); /* XXX Should compare policy against IPsec header history. */ need_auth = 0; for (isr = sp->req; isr != NULL; isr = isr->next) { if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) continue; switch (isr->saidx.proto) { case IPPROTO_ESP: if ((m->m_flags & M_DECRYPTED) == 0) { KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s: ESP m_flags:%x\n", __func__, m->m_flags)); return (1); } if (!need_auth && isr->sav != NULL && isr->sav->tdb_authalgxform != NULL && (m->m_flags & M_AUTHIPDGM) == 0) { KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s: ESP/AH m_flags:%x\n", __func__, m->m_flags)); return (1); } break; case IPPROTO_AH: need_auth = 1; if ((m->m_flags & M_AUTHIPHDR) == 0) { KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s: AH m_flags:%x\n", __func__, m->m_flags)); return (1); } break; case IPPROTO_IPCOMP: /* * We don't really care, as IPcomp document * says that we shouldn't compress small * packets. IPComp policy should always be * treated as being in "use" level. */ break; } } return (0); /* Valid. */ } static int ipsec46_in_reject(struct mbuf *m, struct inpcb *inp) { struct secpolicy *sp; int error; int result; IPSEC_ASSERT(m != NULL, ("null mbuf")); /* * Get SP for this packet. * When we are called from ip_forward(), we call * ipsec_getpolicybyaddr() with IP_FORWARDING flag. */ if (inp == NULL) sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); else sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error); if (sp != NULL) { result = ipsec_in_reject(sp, m); KEY_FREESP(&sp); } else { result = 0; /* XXX Should be panic? * -> No, there may be error. */ } return (result); } /* * Check AH/ESP integrity. * This function is called from tcp_input(), udp_input(), * and {ah,esp}4_input for tunnel mode. */ int ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) { INIT_VNET_IPSEC(curvnet); int result; result = ipsec46_in_reject(m, inp); if (result) V_ipsec4stat.ips_in_polvio++; return (result); } #ifdef INET6 /* * Check AH/ESP integrity. * This function is called from tcp6_input(), udp6_input(), * and {ah,esp}6_input for tunnel mode. */ int ipsec6_in_reject(struct mbuf *m, struct inpcb *inp) { INIT_VNET_IPSEC(curvnet); int result; result = ipsec46_in_reject(m, inp); if (result) V_ipsec6stat.ips_in_polvio++; return (result); } #endif /* * Compute the byte size to be occupied by IPsec header. * In case it is tunnelled, it includes the size of outer IP header. * NOTE: SP passed is freed in this function. */ static size_t ipsec_hdrsiz_internal(struct secpolicy *sp) { INIT_VNET_IPSEC(curvnet); struct ipsecrequest *isr; size_t size; KEYDEBUG(KEYDEBUG_IPSEC_DATA, printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); switch (sp->policy) { case IPSEC_POLICY_DISCARD: case IPSEC_POLICY_BYPASS: case IPSEC_POLICY_NONE: return (0); } IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, ("invalid policy %u", sp->policy)); size = 0; for (isr = sp->req; isr != NULL; isr = isr->next) { size_t clen = 0; switch (isr->saidx.proto) { case IPPROTO_ESP: clen = esp_hdrsiz(isr->sav); break; case IPPROTO_AH: clen = ah_hdrsiz(isr->sav); break; case IPPROTO_IPCOMP: clen = sizeof(struct ipcomp); break; } if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { switch (isr->saidx.dst.sa.sa_family) { case AF_INET: clen += sizeof(struct ip); break; #ifdef INET6 case AF_INET6: clen += sizeof(struct ip6_hdr); break; #endif default: ipseclog((LOG_ERR, "%s: unknown AF %d in " "IPsec tunnel SA\n", __func__, ((struct sockaddr *)&isr->saidx.dst)->sa_family)); break; } } size += clen; } return (size); } /* * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(), * disabled ip6_ipsec_mtu() and ip6_forward(). */ size_t ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) { INIT_VNET_IPSEC(curvnet); struct secpolicy *sp; int error; size_t size; IPSEC_ASSERT(m != NULL, ("null mbuf")); /* Get SP for this packet. * When we are called from ip_forward(), we call * ipsec_getpolicybyaddr() with IP_FORWARDING flag. */ if (inp == NULL) sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); else sp = ipsec_getpolicybysock(m, dir, inp, &error); if (sp != NULL) { size = ipsec_hdrsiz_internal(sp); KEYDEBUG(KEYDEBUG_IPSEC_DATA, printf("%s: size:%lu.\n", __func__, (unsigned long)size)); KEY_FREESP(&sp); } else { size = 0; /* XXX Should be panic? * -> No, we are called w/o knowing if * IPsec processing is needed. */ } return (size); } /* * Check the variable replay window. * ipsec_chkreplay() performs replay check before ICV verification. * ipsec_updatereplay() updates replay bitmap. This must be called after * ICV verification (it also performs replay check, which is usually done * beforehand). * 0 (zero) is returned if packet disallowed, 1 if packet permitted. * * Based on RFC 2401. */ int ipsec_chkreplay(u_int32_t seq, struct secasvar *sav) { const struct secreplay *replay; u_int32_t diff; int fr; u_int32_t wsizeb; /* Constant: bits of window size. */ int frlast; /* Constant: last frame. */ IPSEC_ASSERT(sav != NULL, ("Null SA")); IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); replay = sav->replay; if (replay->wsize == 0) return (1); /* No need to check replay. */ /* Constant. */ frlast = replay->wsize - 1; wsizeb = replay->wsize << 3; /* Sequence number of 0 is invalid. */ if (seq == 0) return (0); /* First time is always okay. */ if (replay->count == 0) return (1); if (seq > replay->lastseq) { /* Larger sequences are okay. */ return (1); } else { /* seq is equal or less than lastseq. */ diff = replay->lastseq - seq; /* Over range to check, i.e. too old or wrapped. */ if (diff >= wsizeb) return (0); fr = frlast - diff / 8; /* This packet already seen? */ if ((replay->bitmap)[fr] & (1 << (diff % 8))) return (0); /* Out of order but good. */ return (1); } } /* * Check replay counter whether to update or not. * OUT: 0: OK * 1: NG */ int ipsec_updatereplay(u_int32_t seq, struct secasvar *sav) { INIT_VNET_IPSEC(curvnet); struct secreplay *replay; u_int32_t diff; int fr; u_int32_t wsizeb; /* Constant: bits of window size. */ int frlast; /* Constant: last frame. */ IPSEC_ASSERT(sav != NULL, ("Null SA")); IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); replay = sav->replay; if (replay->wsize == 0) goto ok; /* No need to check replay. */ /* Constant. */ frlast = replay->wsize - 1; wsizeb = replay->wsize << 3; /* Sequence number of 0 is invalid. */ if (seq == 0) return (1); /* First time. */ if (replay->count == 0) { replay->lastseq = seq; bzero(replay->bitmap, replay->wsize); (replay->bitmap)[frlast] = 1; goto ok; } if (seq > replay->lastseq) { /* seq is larger than lastseq. */ diff = seq - replay->lastseq; /* New larger sequence number. */ if (diff < wsizeb) { /* In window. */ /* Set bit for this packet. */ vshiftl(replay->bitmap, diff, replay->wsize); (replay->bitmap)[frlast] |= 1; } else { /* This packet has a "way larger". */ bzero(replay->bitmap, replay->wsize); (replay->bitmap)[frlast] = 1; } replay->lastseq = seq; /* Larger is good. */ } else { /* seq is equal or less than lastseq. */ diff = replay->lastseq - seq; /* Over range to check, i.e. too old or wrapped. */ if (diff >= wsizeb) return (1); fr = frlast - diff / 8; /* This packet already seen? */ if ((replay->bitmap)[fr] & (1 << (diff % 8))) return (1); /* Mark as seen. */ (replay->bitmap)[fr] |= (1 << (diff % 8)); /* Out of order but good. */ } ok: if (replay->count == ~0) { /* Set overflow flag. */ replay->overflow++; /* Don't increment, no more packets accepted. */ if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) return (1); ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", __func__, replay->overflow, ipsec_logsastr(sav))); } replay->count++; return (0); } /* * Shift variable length buffer to left. * IN: bitmap: pointer to the buffer * nbit: the number of to shift. * wsize: buffer size (bytes). */ static void vshiftl(unsigned char *bitmap, int nbit, int wsize) { int s, j, i; unsigned char over; for (j = 0; j < nbit; j += 8) { s = (nbit - j < 8) ? (nbit - j): 8; bitmap[0] <<= s; for (i = 1; i < wsize; i++) { over = (bitmap[i] >> (8 - s)); bitmap[i] <<= s; bitmap[i-1] |= over; } } } /* Return a printable string for the IPv4 address. */ static char * inet_ntoa4(struct in_addr ina) { static char buf[4][4 * sizeof "123" + 4]; unsigned char *ucp = (unsigned char *) &ina; static int i = 3; /* XXX-BZ Returns static buffer. */ i = (i + 1) % 4; sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff, ucp[2] & 0xff, ucp[3] & 0xff); return (buf[i]); } /* Return a printable string for the address. */ char * ipsec_address(union sockaddr_union* sa) { #ifdef INET6 char ip6buf[INET6_ADDRSTRLEN]; #endif switch (sa->sa.sa_family) { #ifdef INET case AF_INET: return (inet_ntoa4(sa->sin.sin_addr)); #endif /* INET */ #ifdef INET6 case AF_INET6: return (ip6_sprintf(ip6buf, &sa->sin6.sin6_addr)); #endif /* INET6 */ default: return ("(unknown address family)"); } } const char * ipsec_logsastr(struct secasvar *sav) { static char buf[256]; char *p; struct secasindex *saidx = &sav->sah->saidx; IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, ("address family mismatch")); p = buf; snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi)); while (p && *p) p++; /* NB: only use ipsec_address on one address at a time. */ snprintf(p, sizeof (buf) - (p - buf), "src=%s ", ipsec_address(&saidx->src)); while (p && *p) p++; snprintf(p, sizeof (buf) - (p - buf), "dst=%s)", ipsec_address(&saidx->dst)); return (buf); } void ipsec_dumpmbuf(struct mbuf *m) { int totlen; int i; u_char *p; totlen = 0; printf("---\n"); while (m) { p = mtod(m, u_char *); for (i = 0; i < m->m_len; i++) { printf("%02x ", p[i]); totlen++; if (totlen % 16 == 0) printf("\n"); } m = m->m_next; } if (totlen % 16 != 0) printf("\n"); printf("---\n"); } static void ipsec_attach(void) { #ifndef VIMAGE_GLOBALS vnet_mod_register(&vnet_ipsec_modinfo); #else ipsec_iattach(NULL); #endif } static int ipsec_iattach(const void *unused __unused) { INIT_VNET_IPSEC(curvnet); SECPOLICY_LOCK_INIT(&V_ip4_def_policy); V_ip4_def_policy.refcnt = 1; /* NB: disallow free. */ return (0); } SYSINIT(ipsec, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST, ipsec_attach, NULL); /* XXX This stuff doesn't belong here... */ static struct xformsw* xforms = NULL; /* * Register a transform; typically at system startup. */ void xform_register(struct xformsw* xsp) { xsp->xf_next = xforms; xforms = xsp; } /* * Initialize transform support in an sav. */ int xform_init(struct secasvar *sav, int xftype) { struct xformsw *xsp; if (sav->tdb_xform != NULL) /* Previously initialized. */ return (0); for (xsp = xforms; xsp; xsp = xsp->xf_next) if (xsp->xf_type == xftype) return ((*xsp->xf_init)(sav, xsp)); return (EINVAL); }