/* $FreeBSD$ */ /* $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 #ifdef INET6 #include #endif #include #ifdef INET6 #include #endif #include #ifdef INET6 #include #endif #include #include #include /*XXX*/ #include #include #include #include #include #include #ifdef IPSEC_DEBUG int ipsec_debug = 1; #else int ipsec_debug = 0; #endif /* NB: name changed so netstat doesn't use it */ struct newipsecstat newipsecstat; int ip4_ah_offsetmask = 0; /* maybe IP_DF? */ int ip4_ipsec_dfbit = 0; /* DF bit on encap. 0: clear 1: set 2: copy */ int ip4_esp_trans_deflev = IPSEC_LEVEL_USE; int ip4_esp_net_deflev = IPSEC_LEVEL_USE; int ip4_ah_trans_deflev = IPSEC_LEVEL_USE; int ip4_ah_net_deflev = IPSEC_LEVEL_USE; struct secpolicy ip4_def_policy; int ip4_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ int ip4_esp_randpad = -1; /* * Crypto support requirements: * * 1 require hardware support * -1 require software support * 0 take anything */ int crypto_support = 0; SYSCTL_DECL(_net_inet_ipsec); /* net.inet.ipsec */ SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy, CTLFLAG_RW, &ip4_def_policy.policy, 0, ""); SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev, CTLFLAG_RW, &ip4_esp_trans_deflev, 0, ""); SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev, CTLFLAG_RW, &ip4_esp_net_deflev, 0, ""); SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev, CTLFLAG_RW, &ip4_ah_trans_deflev, 0, ""); SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev, CTLFLAG_RW, &ip4_ah_net_deflev, 0, ""); SYSCTL_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos, CTLFLAG_RW, &ah_cleartos, 0, ""); SYSCTL_INT(_net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, ah_offsetmask, CTLFLAG_RW, &ip4_ah_offsetmask, 0, ""); SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit, CTLFLAG_RW, &ip4_ipsec_dfbit, 0, ""); SYSCTL_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn, CTLFLAG_RW, &ip4_ipsec_ecn, 0, ""); SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEBUG, debug, CTLFLAG_RW, &ipsec_debug, 0, ""); SYSCTL_INT(_net_inet_ipsec, IPSECCTL_ESP_RANDPAD, esp_randpad, CTLFLAG_RW, &ip4_esp_randpad, 0, ""); SYSCTL_INT(_net_inet_ipsec, OID_AUTO, crypto_support, CTLFLAG_RW, &crypto_support,0, ""); SYSCTL_STRUCT(_net_inet_ipsec, OID_AUTO, ipsecstats, CTLFLAG_RD, &newipsecstat, newipsecstat, ""); #ifdef REGRESSION /* * 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. */ int ipsec_replay = 0; SYSCTL_INT(_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. */ int ipsec_integrity = 0; SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_integrity, CTLFLAG_RW, &ipsec_integrity, 0, "Emulate man-in-the-middle attack"); #endif #ifdef INET6 int ip6_esp_trans_deflev = IPSEC_LEVEL_USE; int ip6_esp_net_deflev = IPSEC_LEVEL_USE; int ip6_ah_trans_deflev = IPSEC_LEVEL_USE; int ip6_ah_net_deflev = IPSEC_LEVEL_USE; int ip6_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ int ip6_esp_randpad = -1; 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", ""); #endif /* COMPAT_KAME */ SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy, CTLFLAG_RW, &ip4_def_policy.policy, 0, ""); SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev, CTLFLAG_RW, &ip6_esp_trans_deflev, 0, ""); SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev, CTLFLAG_RW, &ip6_esp_net_deflev, 0, ""); SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev, CTLFLAG_RW, &ip6_ah_trans_deflev, 0, ""); SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev, CTLFLAG_RW, &ip6_ah_net_deflev, 0, ""); SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_ECN, ecn, CTLFLAG_RW, &ip6_ipsec_ecn, 0, ""); SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEBUG, debug, CTLFLAG_RW, &ipsec_debug, 0, ""); SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_ESP_RANDPAD, esp_randpad, CTLFLAG_RW, &ip6_esp_randpad, 0, ""); #endif /* INET6 */ static int ipsec4_setspidx_inpcb __P((struct mbuf *, struct inpcb *pcb)); #ifdef INET6 static int ipsec6_setspidx_in6pcb __P((struct mbuf *, struct in6pcb *pcb)); #endif 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 int ipsec_set_policy __P((struct secpolicy **pcb_sp, int optname, caddr_t request, size_t len, int priv)); static int ipsec_get_policy __P((struct secpolicy *pcb_sp, struct mbuf **mp)); static void vshiftl __P((unsigned char *, int, int)); static size_t ipsec_hdrsiz __P((struct secpolicy *)); MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy"); /* * Return a held reference to the default SP. */ static struct secpolicy * key_allocsp_default(const char* where, int tag) { struct secpolicy *sp; KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP key_allocsp_default from %s:%u\n", where, tag)); sp = &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. */ struct secpolicy * ipsec_getpolicybysock(m, dir, inp, error) struct mbuf *m; u_int dir; struct inpcb *inp; int *error; { struct inpcbpolicy *pcbsp = NULL; 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 */ if (inp->inp_vflag & INP_IPV6PROTO) { #ifdef INET6 *error = ipsec6_setspidx_in6pcb(m, inp); pcbsp = inp->in6p_sp; #else *error = EINVAL; /* should not happen */ #endif } else { *error = ipsec4_setspidx_inpcb(m, inp); pcbsp = inp->inp_sp; } if (*error) return NULL; 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(m, dir, flag, error) struct mbuf *m; u_int dir; int flag; int *error; { 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(m, dir, flag, error, inp) struct mbuf *m; u_int dir, flag; int *error; struct inpcb *inp; { 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")); newipsecstat.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); /* fall thru... */ case IPSEC_POLICY_DISCARD: newipsecstat.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 an SA */ *error = key_spdacquire(sp); break; } if (*error != 0) { KEY_FREESP(&sp); sp = NULL; } return sp; } static int ipsec4_setspidx_inpcb(m, pcb) struct mbuf *m; struct inpcb *pcb; { int error; IPSEC_ASSERT(pcb != NULL, ("null pcb")); IPSEC_ASSERT(pcb->inp_sp != NULL, ("null inp_sp")); IPSEC_ASSERT(pcb->inp_sp->sp_out != NULL && pcb->inp_sp->sp_in != NULL, ("null sp_in || sp_out")); error = ipsec_setspidx(m, &pcb->inp_sp->sp_in->spidx, 1); if (error == 0) { pcb->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; pcb->inp_sp->sp_out->spidx = pcb->inp_sp->sp_in->spidx; pcb->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; } else { bzero(&pcb->inp_sp->sp_in->spidx, sizeof (pcb->inp_sp->sp_in->spidx)); bzero(&pcb->inp_sp->sp_out->spidx, sizeof (pcb->inp_sp->sp_in->spidx)); } return error; } #ifdef INET6 static int ipsec6_setspidx_in6pcb(m, pcb) struct mbuf *m; struct in6pcb *pcb; { struct secpolicyindex *spidx; int error; IPSEC_ASSERT(pcb != NULL, ("null pcb")); IPSEC_ASSERT(pcb->in6p_sp != NULL, ("null inp_sp")); IPSEC_ASSERT(pcb->in6p_sp->sp_out != NULL && pcb->in6p_sp->sp_in != NULL, ("null sp_in || sp_out")); bzero(&pcb->in6p_sp->sp_in->spidx, sizeof(*spidx)); bzero(&pcb->in6p_sp->sp_out->spidx, sizeof(*spidx)); spidx = &pcb->in6p_sp->sp_in->spidx; error = ipsec_setspidx(m, spidx, 1); if (error) goto bad; spidx->dir = IPSEC_DIR_INBOUND; spidx = &pcb->in6p_sp->sp_out->spidx; error = ipsec_setspidx(m, spidx, 1); if (error) goto bad; spidx->dir = IPSEC_DIR_OUTBOUND; return 0; bad: bzero(&pcb->in6p_sp->sp_in->spidx, sizeof(*spidx)); bzero(&pcb->in6p_sp->sp_out->spidx, sizeof(*spidx)); return error; } #endif /* * 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(m, spidx, needport) struct mbuf *m; struct secpolicyindex *spidx; int needport; { 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(m, spidx, needport) struct mbuf *m; struct secpolicyindex *spidx; int needport; { int off, nxt; struct tcphdr th; struct udphdr uh; /* 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: default: /* XXX intermediate headers??? */ spidx->ul_proto = nxt; break; } } /* assumes that m is sane */ static int ipsec6_setspidx_ipaddr(m, spidx) 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(p) struct inpcbpolicy *p; { free(p, M_IPSEC_INPCB); } /* initialize policy in PCB */ int ipsec_init_policy(so, pcb_sp) struct socket *so; struct inpcbpolicy **pcb_sp; { 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(old, new) struct inpcbpolicy *old, *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(src) 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(pcb_sp, optname, request, len, priv) struct secpolicy **pcb_sp; int optname; caddr_t request; size_t len; int priv; { 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() 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 (priv == 0 && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) return EACCES; /* allocation 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; } static int ipsec_get_policy(pcb_sp, mp) struct secpolicy *pcb_sp; struct mbuf **mp; { /* sanity check. */ if (pcb_sp == NULL || mp == 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; } int ipsec4_set_policy(inp, optname, request, len, priv) struct inpcb *inp; int optname; caddr_t request; size_t len; int priv; { 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(pcb_sp, optname, request, len, priv); } int ipsec4_get_policy(inp, request, len, mp) struct inpcb *inp; caddr_t request; size_t len; struct mbuf **mp; { 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; } return ipsec_get_policy(pcb_sp, mp); } /* delete policy in PCB */ int ipsec4_delete_pcbpolicy(inp) 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; } #ifdef INET6 int ipsec6_set_policy(in6p, optname, request, len, priv) struct in6pcb *in6p; int optname; caddr_t request; size_t len; int priv; { struct sadb_x_policy *xpl; struct secpolicy **pcb_sp; /* sanity check. */ if (in6p == 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 = &in6p->in6p_sp->sp_in; break; case IPSEC_DIR_OUTBOUND: pcb_sp = &in6p->in6p_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(pcb_sp, optname, request, len, priv); } int ipsec6_get_policy(in6p, request, len, mp) struct in6pcb *in6p; caddr_t request; size_t len; struct mbuf **mp; { struct sadb_x_policy *xpl; struct secpolicy *pcb_sp; /* sanity check. */ if (in6p == NULL || request == NULL || mp == NULL) return EINVAL; IPSEC_ASSERT(in6p->in6p_sp != NULL, ("null in6p_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 = in6p->in6p_sp->sp_in; break; case IPSEC_DIR_OUTBOUND: pcb_sp = in6p->in6p_sp->sp_out; break; default: ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, xpl->sadb_x_policy_dir)); return EINVAL; } return ipsec_get_policy(pcb_sp, mp); } int ipsec6_delete_pcbpolicy(in6p) struct in6pcb *in6p; { IPSEC_ASSERT(in6p != NULL, ("null in6p")); if (in6p->in6p_sp == NULL) return 0; if (in6p->in6p_sp->sp_in != NULL) KEY_FREESP(&in6p->in6p_sp->sp_in); if (in6p->in6p_sp->sp_out != NULL) KEY_FREESP(&in6p->in6p_sp->sp_out); ipsec_delpcbpolicy(in6p->in6p_sp); in6p->in6p_sp = NULL; return 0; } #endif /* * return current level. * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. */ u_int ipsec_get_reqlevel(isr) struct ipsecrequest *isr; { 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) \ ? (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(ip4_esp_trans_deflev); esp_net_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_net_deflev); ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_trans_deflev); ah_net_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_net_deflev); break; #endif #ifdef INET6 case AF_INET6: esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_trans_deflev); esp_net_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_net_deflev); ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_trans_deflev); ah_net_deflev = IPSEC_CHECK_DEFAULT(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) { 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 */ } /* * 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(m, inp) 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); if (result) newipsecstat.ips_in_polvio++; KEY_FREESP(&sp); } else { result = 0; /* XXX should be panic ? * -> No, there may be error. */ } 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(m, inp) struct mbuf *m; struct inpcb *inp; { struct secpolicy *sp = NULL; int error; int result; /* sanity check */ if (m == NULL) return 0; /* XXX should be panic ? */ /* 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); if (result) newipsecstat.ips_in_polvio++; KEY_FREESP(&sp); } else { result = 0; } return result; } #endif /* * compute the byte size to be occupied by IPsec header. * in case it is tunneled, it includes the size of outer IP header. * NOTE: SP passed is free in this function. */ static size_t ipsec_hdrsiz(struct secpolicy *sp) { struct ipsecrequest *isr; size_t siz; 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)); siz = 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; } } siz += clen; } return siz; } /* This function is called from ip_forward() and ipsec4_hdrsize_tcp(). */ size_t ipsec4_hdrsiz(m, dir, inp) struct mbuf *m; u_int dir; struct inpcb *inp; { 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(sp); KEYDEBUG(KEYDEBUG_IPSEC_DATA, printf("%s: size:%lu.\n", __func__, (unsigned long)size)); KEY_FREESP(&sp); } else { size = 0; /* XXX should be panic ? */ } return size; } #ifdef INET6 /* This function is called from ipsec6_hdrsize_tcp(), * and maybe from ip6_forward.() */ size_t ipsec6_hdrsiz(m, dir, in6p) struct mbuf *m; u_int dir; struct in6pcb *in6p; { struct secpolicy *sp; int error; size_t size; IPSEC_ASSERT(m != NULL, ("null mbuf")); IPSEC_ASSERT(in6p == NULL || in6p->in6p_socket != NULL, ("socket w/o inpcb")); /* get SP for this packet */ /* XXX Is it right to call with IP_FORWARDING. */ if (in6p == NULL) sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); else sp = ipsec_getpolicybysock(m, dir, in6p, &error); if (sp == NULL) return 0; size = ipsec_hdrsiz(sp); KEYDEBUG(KEYDEBUG_IPSEC_DATA, printf("%s: size:%lu.\n", __func__, (unsigned long)size)); KEY_FREESP(&sp); return size; } #endif /*INET6*/ /* * 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(seq, sav) 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_SPLASSERT_SOFTNET(__func__); 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(seq, sav) u_int32_t seq; struct secasvar *sav; { struct secreplay *replay; u_int32_t diff; int fr; u_int32_t wsizeb; /* constant: bits of window size */ int frlast; /* constant: last frame */ IPSEC_SPLASSERT_SOFTNET(__func__); 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(bitmap, nbit, wsize) unsigned char *bitmap; int nbit, 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; } /* 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; 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) { switch (sa->sa.sa_family) { #if INET case AF_INET: return inet_ntoa4(sa->sin.sin_addr); #endif /* INET */ #if INET6 case AF_INET6: return ip6_sprintf(&sa->sin6.sin6_addr); #endif /* INET6 */ default: return "(unknown address family)"; } } const char * ipsec_logsastr(sav) 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(m) 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) { SECPOLICY_LOCK_INIT(&ip4_def_policy); ip4_def_policy.refcnt = 1; /* NB: disallow free */ } 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; }