1 /* $KAME: ipsec.c,v 1.103 2001/05/24 07:14:18 sakane Exp $ */ 2 3 /*- 4 * SPDX-License-Identifier: BSD-3-Clause 5 * 6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the project nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 /* 35 * IPsec controller part. 36 */ 37 38 #include "opt_inet.h" 39 #include "opt_inet6.h" 40 #include "opt_ipsec.h" 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/malloc.h> 45 #include <sys/mbuf.h> 46 #include <sys/domain.h> 47 #include <sys/priv.h> 48 #include <sys/protosw.h> 49 #include <sys/socket.h> 50 #include <sys/socketvar.h> 51 #include <sys/errno.h> 52 #include <sys/hhook.h> 53 #include <sys/time.h> 54 #include <sys/kernel.h> 55 #include <sys/syslog.h> 56 #include <sys/sysctl.h> 57 #include <sys/proc.h> 58 59 #include <net/if.h> 60 #include <net/if_enc.h> 61 #include <net/if_var.h> 62 #include <net/vnet.h> 63 64 #include <netinet/in.h> 65 #include <netinet/in_systm.h> 66 #include <netinet/ip.h> 67 #include <netinet/ip_var.h> 68 #include <netinet/in_var.h> 69 #include <netinet/udp.h> 70 #include <netinet/udp_var.h> 71 #include <netinet/tcp.h> 72 #include <netinet/udp.h> 73 74 #include <netinet/ip6.h> 75 #ifdef INET6 76 #include <netinet6/ip6_var.h> 77 #endif 78 #include <netinet/in_pcb.h> 79 #ifdef INET6 80 #include <netinet/icmp6.h> 81 #endif 82 83 #include <sys/types.h> 84 #include <netipsec/ipsec.h> 85 #ifdef INET6 86 #include <netipsec/ipsec6.h> 87 #endif 88 #include <netipsec/ipsec_offload.h> 89 #include <netipsec/ah_var.h> 90 #include <netipsec/esp_var.h> 91 #include <netipsec/ipcomp.h> /*XXX*/ 92 #include <netipsec/ipcomp_var.h> 93 #include <netipsec/ipsec_support.h> 94 95 #include <netipsec/key.h> 96 #include <netipsec/keydb.h> 97 #include <netipsec/key_debug.h> 98 99 #include <netipsec/xform.h> 100 101 #include <machine/in_cksum.h> 102 103 #include <opencrypto/cryptodev.h> 104 105 /* NB: name changed so netstat doesn't use it. */ 106 VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec4stat); 107 VNET_PCPUSTAT_SYSINIT(ipsec4stat); 108 109 #ifdef VIMAGE 110 VNET_PCPUSTAT_SYSUNINIT(ipsec4stat); 111 #endif /* VIMAGE */ 112 113 /* DF bit on encap. 0: clear 1: set 2: copy */ 114 VNET_DEFINE(int, ip4_ipsec_dfbit) = 0; 115 VNET_DEFINE(int, ip4_ipsec_min_pmtu) = 576; 116 VNET_DEFINE(int, ip4_esp_trans_deflev) = IPSEC_LEVEL_USE; 117 VNET_DEFINE(int, ip4_esp_net_deflev) = IPSEC_LEVEL_USE; 118 VNET_DEFINE(int, ip4_ah_trans_deflev) = IPSEC_LEVEL_USE; 119 VNET_DEFINE(int, ip4_ah_net_deflev) = IPSEC_LEVEL_USE; 120 /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 121 VNET_DEFINE(int, ip4_ipsec_ecn) = 0; 122 VNET_DEFINE(int, ip4_ipsec_random_id) = 0; 123 124 VNET_DEFINE_STATIC(int, ip4_filtertunnel) = 0; 125 #define V_ip4_filtertunnel VNET(ip4_filtertunnel) 126 VNET_DEFINE_STATIC(int, check_policy_history) = 0; 127 #define V_check_policy_history VNET(check_policy_history) 128 VNET_DEFINE_STATIC(struct secpolicy *, def_policy) = NULL; 129 #define V_def_policy VNET(def_policy) 130 static int 131 sysctl_def_policy(SYSCTL_HANDLER_ARGS) 132 { 133 int error, value; 134 135 value = V_def_policy->policy; 136 error = sysctl_handle_int(oidp, &value, 0, req); 137 if (error == 0) { 138 if (value != IPSEC_POLICY_DISCARD && 139 value != IPSEC_POLICY_NONE) 140 return (EINVAL); 141 V_def_policy->policy = value; 142 } 143 return (error); 144 } 145 146 /* 147 * Crypto support requirements: 148 * 149 * 1 require hardware support 150 * -1 require software support 151 * 0 take anything 152 */ 153 VNET_DEFINE(int, crypto_support) = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE; 154 155 /* 156 * Use asynchronous mode to parallelize crypto jobs: 157 * 158 * 0 - disabled 159 * 1 - enabled 160 */ 161 VNET_DEFINE(int, async_crypto) = 0; 162 163 /* 164 * TCP/UDP checksum handling policy for transport mode NAT-T (RFC3948) 165 * 166 * 0 - auto: incrementally recompute, when checksum delta is known; 167 * if checksum delta isn't known, reset checksum to zero for UDP, 168 * and mark csum_flags as valid for TCP. 169 * 1 - fully recompute TCP/UDP checksum. 170 */ 171 VNET_DEFINE(int, natt_cksum_policy) = 0; 172 173 FEATURE(ipsec, "Internet Protocol Security (IPsec)"); 174 FEATURE(ipsec_natt, "UDP Encapsulation of IPsec ESP Packets ('NAT-T')"); 175 176 /* net.inet.ipsec */ 177 SYSCTL_PROC(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy, 178 CTLTYPE_INT | CTLFLAG_VNET | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 179 0, 0, sysctl_def_policy, "I", 180 "IPsec default policy."); 181 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev, 182 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_esp_trans_deflev), 0, 183 "Default ESP transport mode level"); 184 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev, 185 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_esp_net_deflev), 0, 186 "Default ESP tunnel mode level."); 187 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev, 188 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ah_trans_deflev), 0, 189 "AH transfer mode default level."); 190 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev, 191 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ah_net_deflev), 0, 192 "AH tunnel mode default level."); 193 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos, 194 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ah_cleartos), 0, 195 "If set, clear type-of-service field when doing AH computation."); 196 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit, 197 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ipsec_dfbit), 0, 198 "Do not fragment bit on encap."); 199 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_MIN_PMTU, min_pmtu, 200 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ipsec_min_pmtu), 0, 201 "Lowest acceptable PMTU value."); 202 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn, 203 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ipsec_ecn), 0, 204 "Explicit Congestion Notification handling."); 205 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_RANDOM_ID, random_id, 206 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ipsec_random_id), 0, 207 "Assign random ip_id values."); 208 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, crypto_support, 209 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(crypto_support), 0, 210 "Crypto driver selection."); 211 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, async_crypto, 212 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(async_crypto), 0, 213 "Use asynchronous mode to parallelize crypto jobs."); 214 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, check_policy_history, 215 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(check_policy_history), 0, 216 "Use strict check of inbound packets to security policy compliance."); 217 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, natt_cksum_policy, 218 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(natt_cksum_policy), 0, 219 "Method to fix TCP/UDP checksum for transport mode IPsec after NAT."); 220 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, filtertunnel, 221 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_filtertunnel), 0, 222 "If set, filter packets from an IPsec tunnel."); 223 SYSCTL_VNET_PCPUSTAT(_net_inet_ipsec, OID_AUTO, ipsecstats, struct ipsecstat, 224 ipsec4stat, "IPsec IPv4 statistics."); 225 226 #ifdef REGRESSION 227 /* 228 * When set to 1, IPsec will send packets with the same sequence number. 229 * This allows to verify if the other side has proper replay attacks detection. 230 */ 231 VNET_DEFINE(int, ipsec_replay) = 0; 232 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_replay, 233 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipsec_replay), 0, 234 "Emulate replay attack"); 235 /* 236 * When set 1, IPsec will send packets with corrupted HMAC. 237 * This allows to verify if the other side properly detects modified packets. 238 */ 239 VNET_DEFINE(int, ipsec_integrity) = 0; 240 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_integrity, 241 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipsec_integrity), 0, 242 "Emulate man-in-the-middle attack"); 243 #endif 244 245 #ifdef INET6 246 VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec6stat); 247 VNET_PCPUSTAT_SYSINIT(ipsec6stat); 248 249 #ifdef VIMAGE 250 VNET_PCPUSTAT_SYSUNINIT(ipsec6stat); 251 #endif /* VIMAGE */ 252 253 VNET_DEFINE(int, ip6_esp_trans_deflev) = IPSEC_LEVEL_USE; 254 VNET_DEFINE(int, ip6_esp_net_deflev) = IPSEC_LEVEL_USE; 255 VNET_DEFINE(int, ip6_ah_trans_deflev) = IPSEC_LEVEL_USE; 256 VNET_DEFINE(int, ip6_ah_net_deflev) = IPSEC_LEVEL_USE; 257 VNET_DEFINE(int, ip6_ipsec_ecn) = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 258 259 VNET_DEFINE_STATIC(int, ip6_filtertunnel) = 0; 260 #define V_ip6_filtertunnel VNET(ip6_filtertunnel) 261 262 /* net.inet6.ipsec6 */ 263 SYSCTL_PROC(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy, 264 CTLTYPE_INT | CTLFLAG_VNET | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 265 0, 0, sysctl_def_policy, "I", 266 "IPsec default policy."); 267 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev, 268 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_esp_trans_deflev), 0, 269 "Default ESP transport mode level."); 270 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev, 271 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_esp_net_deflev), 0, 272 "Default ESP tunnel mode level."); 273 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev, 274 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ah_trans_deflev), 0, 275 "AH transfer mode default level."); 276 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev, 277 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ah_net_deflev), 0, 278 "AH tunnel mode default level."); 279 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_ECN, ecn, 280 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ipsec_ecn), 0, 281 "Explicit Congestion Notification handling."); 282 SYSCTL_INT(_net_inet6_ipsec6, OID_AUTO, filtertunnel, 283 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_filtertunnel), 0, 284 "If set, filter packets from an IPsec tunnel."); 285 SYSCTL_VNET_PCPUSTAT(_net_inet6_ipsec6, IPSECCTL_STATS, ipsecstats, 286 struct ipsecstat, ipsec6stat, "IPsec IPv6 statistics."); 287 #endif /* INET6 */ 288 289 static int ipsec_in_reject(struct secpolicy *, struct inpcb *, 290 const struct mbuf *); 291 292 #ifdef INET 293 static void ipsec4_get_ulp(const struct mbuf *, const struct ip *, 294 struct secpolicyindex *, int); 295 static void ipsec4_setspidx_ipaddr(const struct mbuf *, struct ip *, 296 struct secpolicyindex *); 297 #endif 298 #ifdef INET6 299 static void ipsec6_get_ulp(const struct mbuf *m, struct secpolicyindex *, int); 300 static void ipsec6_setspidx_ipaddr(const struct mbuf *, 301 struct secpolicyindex *); 302 #endif 303 304 /* 305 * Return a held reference to the default SP. 306 */ 307 static struct secpolicy * 308 key_allocsp_default(void) 309 { 310 311 key_addref(V_def_policy); 312 return (V_def_policy); 313 } 314 315 static void 316 ipsec_invalidate_cache(struct inpcb *inp, u_int dir) 317 { 318 struct secpolicy *sp; 319 320 INP_WLOCK_ASSERT(inp); 321 if (dir == IPSEC_DIR_OUTBOUND) { 322 if (inp->inp_sp->flags & INP_INBOUND_POLICY) 323 return; 324 sp = inp->inp_sp->sp_in; 325 inp->inp_sp->sp_in = NULL; 326 } else { 327 if (inp->inp_sp->flags & INP_OUTBOUND_POLICY) 328 return; 329 sp = inp->inp_sp->sp_out; 330 inp->inp_sp->sp_out = NULL; 331 } 332 if (sp != NULL) 333 key_freesp(&sp); /* release extra reference */ 334 } 335 336 static void 337 ipsec_cachepolicy(struct inpcb *inp, struct secpolicy *sp, u_int dir) 338 { 339 uint32_t genid; 340 int downgrade; 341 342 INP_LOCK_ASSERT(inp); 343 344 if (dir == IPSEC_DIR_OUTBOUND) { 345 /* Do we have configured PCB policy? */ 346 if (inp->inp_sp->flags & INP_OUTBOUND_POLICY) 347 return; 348 /* Another thread has already set cached policy */ 349 if (inp->inp_sp->sp_out != NULL) 350 return; 351 /* 352 * Do not cache OUTBOUND policy if PCB isn't connected, 353 * i.e. foreign address is INADDR_ANY/UNSPECIFIED. 354 */ 355 #ifdef INET 356 if ((inp->inp_vflag & INP_IPV4) != 0 && 357 inp->inp_faddr.s_addr == INADDR_ANY) 358 return; 359 #endif 360 #ifdef INET6 361 if ((inp->inp_vflag & INP_IPV6) != 0 && 362 IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) 363 return; 364 #endif 365 } else { 366 /* Do we have configured PCB policy? */ 367 if (inp->inp_sp->flags & INP_INBOUND_POLICY) 368 return; 369 /* Another thread has already set cached policy */ 370 if (inp->inp_sp->sp_in != NULL) 371 return; 372 /* 373 * Do not cache INBOUND policy for listen socket, 374 * that is bound to INADDR_ANY/UNSPECIFIED address. 375 */ 376 #ifdef INET 377 if ((inp->inp_vflag & INP_IPV4) != 0 && 378 inp->inp_faddr.s_addr == INADDR_ANY) 379 return; 380 #endif 381 #ifdef INET6 382 if ((inp->inp_vflag & INP_IPV6) != 0 && 383 IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) 384 return; 385 #endif 386 } 387 downgrade = 0; 388 if (!INP_WLOCKED(inp)) { 389 if ((downgrade = INP_TRY_UPGRADE(inp)) == 0) 390 return; 391 } 392 if (dir == IPSEC_DIR_OUTBOUND) 393 inp->inp_sp->sp_out = sp; 394 else 395 inp->inp_sp->sp_in = sp; 396 /* 397 * SP is already referenced by the lookup code. 398 * We take extra reference here to avoid race in the 399 * ipsec_getpcbpolicy() function - SP will not be freed in the 400 * time between we take SP pointer from the cache and key_addref() 401 * call. 402 */ 403 key_addref(sp); 404 genid = key_getspgen(); 405 if (genid != inp->inp_sp->genid) { 406 ipsec_invalidate_cache(inp, dir); 407 inp->inp_sp->genid = genid; 408 } 409 KEYDBG(IPSEC_STAMP, 410 printf("%s: PCB(%p): cached %s SP(%p)\n", 411 __func__, inp, dir == IPSEC_DIR_OUTBOUND ? "OUTBOUND": 412 "INBOUND", sp)); 413 if (downgrade != 0) 414 INP_DOWNGRADE(inp); 415 } 416 417 static struct secpolicy * 418 ipsec_checkpolicy(struct secpolicy *sp, struct inpcb *inp, int *error) 419 { 420 421 /* Save found OUTBOUND policy into PCB SP cache. */ 422 if (inp != NULL && inp->inp_sp != NULL && inp->inp_sp->sp_out == NULL) 423 ipsec_cachepolicy(inp, sp, IPSEC_DIR_OUTBOUND); 424 425 switch (sp->policy) { 426 default: 427 printf("%s: invalid policy %u\n", __func__, sp->policy); 428 /* FALLTHROUGH */ 429 case IPSEC_POLICY_DISCARD: 430 *error = -EINVAL; /* Packet is discarded by caller. */ 431 /* FALLTHROUGH */ 432 case IPSEC_POLICY_BYPASS: 433 case IPSEC_POLICY_NONE: 434 key_freesp(&sp); 435 sp = NULL; /* NB: force NULL result. */ 436 break; 437 case IPSEC_POLICY_IPSEC: 438 /* XXXAE: handle LARVAL SP */ 439 break; 440 } 441 KEYDBG(IPSEC_DUMP, 442 printf("%s: get SP(%p), error %d\n", __func__, sp, *error)); 443 return (sp); 444 } 445 446 static struct secpolicy * 447 ipsec_getpcbpolicy(struct inpcb *inp, u_int dir) 448 { 449 struct secpolicy *sp; 450 int flags, downgrade; 451 452 if (inp == NULL || inp->inp_sp == NULL) 453 return (NULL); 454 455 INP_LOCK_ASSERT(inp); 456 457 flags = inp->inp_sp->flags; 458 if (dir == IPSEC_DIR_OUTBOUND) { 459 sp = inp->inp_sp->sp_out; 460 flags &= INP_OUTBOUND_POLICY; 461 } else { 462 sp = inp->inp_sp->sp_in; 463 flags &= INP_INBOUND_POLICY; 464 } 465 /* 466 * Check flags. If we have PCB SP, just return it. 467 * Otherwise we need to check that cached SP entry isn't stale. 468 */ 469 if (flags == 0) { 470 if (sp == NULL) 471 return (NULL); 472 if (inp->inp_sp->genid != key_getspgen()) { 473 /* Invalidate the cache. */ 474 downgrade = 0; 475 if (!INP_WLOCKED(inp)) { 476 if ((downgrade = INP_TRY_UPGRADE(inp)) == 0) 477 return (NULL); 478 } 479 ipsec_invalidate_cache(inp, IPSEC_DIR_OUTBOUND); 480 ipsec_invalidate_cache(inp, IPSEC_DIR_INBOUND); 481 if (downgrade != 0) 482 INP_DOWNGRADE(inp); 483 return (NULL); 484 } 485 KEYDBG(IPSEC_STAMP, 486 printf("%s: PCB(%p): cache hit SP(%p)\n", 487 __func__, inp, sp)); 488 /* Return referenced cached policy */ 489 } 490 key_addref(sp); 491 return (sp); 492 } 493 494 #ifdef INET 495 static void 496 ipsec4_get_ulp(const struct mbuf *m, const struct ip *ip1, 497 struct secpolicyindex *spidx, int needport) 498 { 499 uint8_t nxt; 500 int off; 501 502 /* Sanity check. */ 503 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip), 504 ("packet too short")); 505 506 if (ip1->ip_off & htons(IP_MF | IP_OFFMASK)) 507 goto done; 508 off = ip1->ip_hl << 2; 509 nxt = ip1->ip_p; 510 511 while (off < m->m_pkthdr.len) { 512 struct ip6_ext ip6e; 513 struct tcphdr th; 514 struct udphdr uh; 515 516 switch (nxt) { 517 case IPPROTO_TCP: 518 spidx->ul_proto = nxt; 519 if (!needport) 520 goto done_proto; 521 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 522 goto done; 523 m_copydata(m, off, sizeof (th), (caddr_t) &th); 524 spidx->src.sin.sin_port = th.th_sport; 525 spidx->dst.sin.sin_port = th.th_dport; 526 return; 527 case IPPROTO_UDP: 528 spidx->ul_proto = nxt; 529 if (!needport) 530 goto done_proto; 531 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 532 goto done; 533 m_copydata(m, off, sizeof (uh), (caddr_t) &uh); 534 spidx->src.sin.sin_port = uh.uh_sport; 535 spidx->dst.sin.sin_port = uh.uh_dport; 536 return; 537 case IPPROTO_AH: 538 if (off + sizeof(ip6e) > m->m_pkthdr.len) 539 goto done; 540 /* XXX Sigh, this works but is totally bogus. */ 541 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e); 542 off += (ip6e.ip6e_len + 2) << 2; 543 nxt = ip6e.ip6e_nxt; 544 break; 545 case IPPROTO_ICMP: 546 default: 547 /* XXX Intermediate headers??? */ 548 spidx->ul_proto = nxt; 549 goto done_proto; 550 } 551 } 552 done: 553 spidx->ul_proto = IPSEC_ULPROTO_ANY; 554 done_proto: 555 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 556 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 557 KEYDBG(IPSEC_DUMP, 558 printf("%s: ", __func__); kdebug_secpolicyindex(spidx, NULL)); 559 } 560 561 static void 562 ipsec4_setspidx_ipaddr(const struct mbuf *m, struct ip *ip1, 563 struct secpolicyindex *spidx) 564 { 565 566 ipsec4_setsockaddrs(m, ip1, &spidx->src, &spidx->dst); 567 spidx->prefs = sizeof(struct in_addr) << 3; 568 spidx->prefd = sizeof(struct in_addr) << 3; 569 } 570 571 static struct secpolicy * 572 ipsec4_getpolicy(const struct mbuf *m, struct inpcb *inp, struct ip *ip1, 573 u_int dir, int needport) 574 { 575 struct secpolicyindex spidx; 576 struct secpolicy *sp; 577 578 sp = ipsec_getpcbpolicy(inp, dir); 579 if (sp == NULL && key_havesp(dir)) { 580 /* Make an index to look for a policy. */ 581 ipsec4_setspidx_ipaddr(m, ip1, &spidx); 582 ipsec4_get_ulp(m, ip1, &spidx, needport); 583 spidx.dir = dir; 584 sp = key_allocsp(&spidx, dir); 585 } 586 if (sp == NULL) /* No SP found, use system default. */ 587 sp = key_allocsp_default(); 588 return (sp); 589 } 590 591 /* 592 * Check security policy for *OUTBOUND* IPv4 packet. 593 */ 594 struct secpolicy * 595 ipsec4_checkpolicy(const struct mbuf *m, struct inpcb *inp, struct ip *ip1, 596 int *error, int needport) 597 { 598 struct secpolicy *sp; 599 600 *error = 0; 601 sp = ipsec4_getpolicy(m, inp, ip1, IPSEC_DIR_OUTBOUND, needport); 602 if (sp != NULL) 603 sp = ipsec_checkpolicy(sp, inp, error); 604 if (sp == NULL) { 605 switch (*error) { 606 case 0: /* No IPsec required: BYPASS or NONE */ 607 break; 608 case -EINVAL: 609 IPSECSTAT_INC(ips_out_polvio); 610 break; 611 default: 612 IPSECSTAT_INC(ips_out_inval); 613 } 614 } 615 KEYDBG(IPSEC_STAMP, 616 printf("%s: using SP(%p), error %d\n", __func__, sp, *error)); 617 if (sp != NULL) 618 KEYDBG(IPSEC_DATA, kdebug_secpolicy(sp)); 619 return (sp); 620 } 621 622 /* 623 * Check IPv4 packet against *INBOUND* security policy. 624 * This function is called from tcp_input(), udp_input(), 625 * rip_input() and sctp_input(). 626 */ 627 int 628 ipsec4_in_reject1(const struct mbuf *m, struct ip *ip1, struct inpcb *inp) 629 { 630 struct secpolicy *sp; 631 #ifdef IPSEC_OFFLOAD 632 struct ipsec_accel_in_tag *tag; 633 #endif 634 struct ip ip_hdr; 635 int result; 636 637 #ifdef IPSEC_OFFLOAD 638 tag = ipsec_accel_input_tag_lookup(m); 639 if (tag != NULL) 640 return (0); 641 #endif 642 643 if (ip1 == NULL) { 644 ip1 = &ip_hdr; 645 m_copydata(m, 0, sizeof(*ip1), (char *)ip1); 646 } 647 648 sp = ipsec4_getpolicy(m, inp, ip1, IPSEC_DIR_INBOUND, 0); 649 result = ipsec_in_reject(sp, inp, m); 650 key_freesp(&sp); 651 if (result != 0) 652 IPSECSTAT_INC(ips_in_polvio); 653 return (result); 654 } 655 656 int 657 ipsec4_in_reject(const struct mbuf *m, struct inpcb *inp) 658 { 659 return (ipsec4_in_reject1(m, NULL, inp)); 660 } 661 662 /* 663 * IPSEC_CAP() method implementation for IPv4. 664 */ 665 int 666 ipsec4_capability(struct mbuf *m, u_int cap) 667 { 668 669 switch (cap) { 670 case IPSEC_CAP_BYPASS_FILTER: 671 /* 672 * Bypass packet filtering for packets previously handled 673 * by IPsec. 674 */ 675 if (!V_ip4_filtertunnel && 676 m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL) != NULL) 677 return (1); 678 return (0); 679 case IPSEC_CAP_OPERABLE: 680 /* Do we have active security policies? */ 681 return (key_havesp_any()); 682 }; 683 return (EOPNOTSUPP); 684 } 685 686 #endif /* INET */ 687 688 #ifdef INET6 689 static void 690 ipsec6_get_ulp(const struct mbuf *m, struct secpolicyindex *spidx, 691 int needport) 692 { 693 struct tcphdr th; 694 struct udphdr uh; 695 struct icmp6_hdr ih; 696 int off, nxt; 697 698 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip6_hdr), 699 ("packet too short")); 700 701 /* Set default. */ 702 spidx->ul_proto = IPSEC_ULPROTO_ANY; 703 spidx->src.sin6.sin6_port = IPSEC_PORT_ANY; 704 spidx->dst.sin6.sin6_port = IPSEC_PORT_ANY; 705 706 nxt = -1; 707 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 708 if (off < 0 || m->m_pkthdr.len < off) 709 return; 710 711 switch (nxt) { 712 case IPPROTO_TCP: 713 spidx->ul_proto = nxt; 714 if (!needport) 715 break; 716 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 717 break; 718 m_copydata(m, off, sizeof(th), (caddr_t)&th); 719 spidx->src.sin6.sin6_port = th.th_sport; 720 spidx->dst.sin6.sin6_port = th.th_dport; 721 break; 722 case IPPROTO_UDP: 723 spidx->ul_proto = nxt; 724 if (!needport) 725 break; 726 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 727 break; 728 m_copydata(m, off, sizeof(uh), (caddr_t)&uh); 729 spidx->src.sin6.sin6_port = uh.uh_sport; 730 spidx->dst.sin6.sin6_port = uh.uh_dport; 731 break; 732 case IPPROTO_ICMPV6: 733 spidx->ul_proto = nxt; 734 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 735 break; 736 m_copydata(m, off, sizeof(ih), (caddr_t)&ih); 737 spidx->src.sin6.sin6_port = htons((uint16_t)ih.icmp6_type); 738 spidx->dst.sin6.sin6_port = htons((uint16_t)ih.icmp6_code); 739 break; 740 default: 741 /* XXX Intermediate headers??? */ 742 spidx->ul_proto = nxt; 743 break; 744 } 745 KEYDBG(IPSEC_DUMP, 746 printf("%s: ", __func__); kdebug_secpolicyindex(spidx, NULL)); 747 } 748 749 static void 750 ipsec6_setspidx_ipaddr(const struct mbuf *m, struct secpolicyindex *spidx) 751 { 752 753 ipsec6_setsockaddrs(m, &spidx->src, &spidx->dst); 754 spidx->prefs = sizeof(struct in6_addr) << 3; 755 spidx->prefd = sizeof(struct in6_addr) << 3; 756 } 757 758 static struct secpolicy * 759 ipsec6_getpolicy(const struct mbuf *m, struct inpcb *inp, u_int dir, 760 int needport) 761 { 762 struct secpolicyindex spidx; 763 struct secpolicy *sp; 764 765 sp = ipsec_getpcbpolicy(inp, dir); 766 if (sp == NULL && key_havesp(dir)) { 767 /* Make an index to look for a policy. */ 768 ipsec6_setspidx_ipaddr(m, &spidx); 769 ipsec6_get_ulp(m, &spidx, needport); 770 spidx.dir = dir; 771 sp = key_allocsp(&spidx, dir); 772 } 773 if (sp == NULL) /* No SP found, use system default. */ 774 sp = key_allocsp_default(); 775 return (sp); 776 } 777 778 /* 779 * Check security policy for *OUTBOUND* IPv6 packet. 780 */ 781 struct secpolicy * 782 ipsec6_checkpolicy(const struct mbuf *m, struct inpcb *inp, int *error, 783 int needport) 784 { 785 struct secpolicy *sp; 786 787 *error = 0; 788 sp = ipsec6_getpolicy(m, inp, IPSEC_DIR_OUTBOUND, needport); 789 if (sp != NULL) 790 sp = ipsec_checkpolicy(sp, inp, error); 791 if (sp == NULL) { 792 switch (*error) { 793 case 0: /* No IPsec required: BYPASS or NONE */ 794 break; 795 case -EINVAL: 796 IPSEC6STAT_INC(ips_out_polvio); 797 break; 798 default: 799 IPSEC6STAT_INC(ips_out_inval); 800 } 801 } 802 KEYDBG(IPSEC_STAMP, 803 printf("%s: using SP(%p), error %d\n", __func__, sp, *error)); 804 if (sp != NULL) 805 KEYDBG(IPSEC_DATA, kdebug_secpolicy(sp)); 806 return (sp); 807 } 808 809 /* 810 * Check IPv6 packet against inbound security policy. 811 * This function is called from tcp6_input(), udp6_input(), 812 * rip6_input() and sctp_input(). 813 */ 814 int 815 ipsec6_in_reject(const struct mbuf *m, struct inpcb *inp) 816 { 817 struct secpolicy *sp; 818 #ifdef IPSEC_OFFLOAD 819 struct ipsec_accel_in_tag *tag; 820 #endif 821 int result; 822 823 #ifdef IPSEC_OFFLOAD 824 tag = ipsec_accel_input_tag_lookup(m); 825 if (tag != NULL) 826 return (0); 827 #endif 828 sp = ipsec6_getpolicy(m, inp, IPSEC_DIR_INBOUND, 0); 829 result = ipsec_in_reject(sp, inp, m); 830 key_freesp(&sp); 831 if (result) 832 IPSEC6STAT_INC(ips_in_polvio); 833 return (result); 834 } 835 836 /* 837 * IPSEC_CAP() method implementation for IPv6. 838 */ 839 int 840 ipsec6_capability(struct mbuf *m, u_int cap) 841 { 842 843 switch (cap) { 844 case IPSEC_CAP_BYPASS_FILTER: 845 /* 846 * Bypass packet filtering for packets previously handled 847 * by IPsec. 848 */ 849 if (!V_ip6_filtertunnel && 850 m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL) != NULL) 851 return (1); 852 return (0); 853 case IPSEC_CAP_OPERABLE: 854 /* Do we have active security policies? */ 855 return (key_havesp_any()); 856 }; 857 return (EOPNOTSUPP); 858 } 859 #endif /* INET6 */ 860 861 int 862 ipsec_run_hhooks(struct ipsec_ctx_data *ctx, int type) 863 { 864 int idx; 865 866 switch (ctx->af) { 867 #ifdef INET 868 case AF_INET: 869 idx = HHOOK_IPSEC_INET; 870 break; 871 #endif 872 #ifdef INET6 873 case AF_INET6: 874 idx = HHOOK_IPSEC_INET6; 875 break; 876 #endif 877 default: 878 return (EPFNOSUPPORT); 879 } 880 if (type == HHOOK_TYPE_IPSEC_IN) 881 HHOOKS_RUN_IF(V_ipsec_hhh_in[idx], ctx, NULL); 882 else 883 HHOOKS_RUN_IF(V_ipsec_hhh_out[idx], ctx, NULL); 884 if (*ctx->mp == NULL) 885 return (EACCES); 886 return (0); 887 } 888 889 /* 890 * Return current level. 891 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 892 */ 893 u_int 894 ipsec_get_reqlevel(struct secpolicy *sp, u_int idx) 895 { 896 struct ipsecrequest *isr; 897 u_int esp_trans_deflev, esp_net_deflev; 898 u_int ah_trans_deflev, ah_net_deflev; 899 u_int level = 0; 900 901 IPSEC_ASSERT(idx < sp->tcount, ("Wrong IPsec request index %d", idx)); 902 /* XXX Note that we have ipseclog() expanded here - code sync issue. */ 903 #define IPSEC_CHECK_DEFAULT(lev) \ 904 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE && \ 905 (lev) != IPSEC_LEVEL_UNIQUE) \ 906 ? (V_ipsec_debug ? \ 907 log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\ 908 (lev), IPSEC_LEVEL_REQUIRE) : 0), \ 909 (lev) = IPSEC_LEVEL_REQUIRE, (lev) : (lev)) 910 911 /* 912 * IPsec VTI uses unique security policy with fake spidx filled 913 * with zeroes. Just return IPSEC_LEVEL_REQUIRE instead of doing 914 * full level lookup for such policies. 915 */ 916 if (sp->state == IPSEC_SPSTATE_IFNET) { 917 IPSEC_ASSERT(sp->req[idx]->level == IPSEC_LEVEL_UNIQUE, 918 ("Wrong IPsec request level %d", sp->req[idx]->level)); 919 return (IPSEC_LEVEL_REQUIRE); 920 } 921 922 /* Set default level. */ 923 switch (sp->spidx.src.sa.sa_family) { 924 #ifdef INET 925 case AF_INET: 926 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev); 927 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev); 928 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev); 929 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev); 930 break; 931 #endif 932 #ifdef INET6 933 case AF_INET6: 934 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev); 935 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev); 936 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev); 937 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev); 938 break; 939 #endif /* INET6 */ 940 default: 941 panic("%s: unknown af %u", 942 __func__, sp->spidx.src.sa.sa_family); 943 } 944 945 #undef IPSEC_CHECK_DEFAULT 946 947 isr = sp->req[idx]; 948 /* Set level. */ 949 switch (isr->level) { 950 case IPSEC_LEVEL_DEFAULT: 951 switch (isr->saidx.proto) { 952 case IPPROTO_ESP: 953 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 954 level = esp_net_deflev; 955 else 956 level = esp_trans_deflev; 957 break; 958 case IPPROTO_AH: 959 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 960 level = ah_net_deflev; 961 else 962 level = ah_trans_deflev; 963 break; 964 case IPPROTO_IPCOMP: 965 /* 966 * We don't really care, as IPcomp document says that 967 * we shouldn't compress small packets. 968 */ 969 level = IPSEC_LEVEL_USE; 970 break; 971 default: 972 panic("%s: Illegal protocol defined %u\n", __func__, 973 isr->saidx.proto); 974 } 975 break; 976 977 case IPSEC_LEVEL_USE: 978 case IPSEC_LEVEL_REQUIRE: 979 level = isr->level; 980 break; 981 case IPSEC_LEVEL_UNIQUE: 982 level = IPSEC_LEVEL_REQUIRE; 983 break; 984 985 default: 986 panic("%s: Illegal IPsec level %u\n", __func__, isr->level); 987 } 988 989 return (level); 990 } 991 992 static int 993 ipsec_check_history(const struct mbuf *m, struct secpolicy *sp, u_int idx) 994 { 995 struct xform_history *xh; 996 struct m_tag *mtag; 997 998 mtag = NULL; 999 while ((mtag = m_tag_find(__DECONST(struct mbuf *, m), 1000 PACKET_TAG_IPSEC_IN_DONE, mtag)) != NULL) { 1001 xh = (struct xform_history *)(mtag + 1); 1002 KEYDBG(IPSEC_DATA, 1003 char buf[IPSEC_ADDRSTRLEN]; 1004 printf("%s: mode %s proto %u dst %s\n", __func__, 1005 kdebug_secasindex_mode(xh->mode), xh->proto, 1006 ipsec_address(&xh->dst, buf, sizeof(buf)))); 1007 if (xh->proto != sp->req[idx]->saidx.proto) 1008 continue; 1009 /* If SA had IPSEC_MODE_ANY, consider this as match. */ 1010 if (xh->mode != sp->req[idx]->saidx.mode && 1011 xh->mode != IPSEC_MODE_ANY) 1012 continue; 1013 /* 1014 * For transport mode IPsec request doesn't contain 1015 * addresses. We need to use address from spidx. 1016 */ 1017 if (sp->req[idx]->saidx.mode == IPSEC_MODE_TRANSPORT) { 1018 if (key_sockaddrcmp_withmask(&xh->dst.sa, 1019 &sp->spidx.dst.sa, sp->spidx.prefd) != 0) 1020 continue; 1021 } else { 1022 if (key_sockaddrcmp(&xh->dst.sa, 1023 &sp->req[idx]->saidx.dst.sa, 0) != 0) 1024 continue; 1025 } 1026 return (0); /* matched */ 1027 } 1028 return (1); 1029 } 1030 1031 /* 1032 * Check security policy requirements against the actual 1033 * packet contents. Return one if the packet should be 1034 * rejected as "invalid"; otherwise return zero to have the 1035 * packet treated as "valid". 1036 * 1037 * OUT: 1038 * 0: valid 1039 * 1: invalid 1040 */ 1041 static int 1042 ipsec_in_reject(struct secpolicy *sp, struct inpcb *inp, const struct mbuf *m) 1043 { 1044 int i; 1045 1046 KEYDBG(IPSEC_STAMP, 1047 printf("%s: PCB(%p): using SP(%p)\n", __func__, inp, sp)); 1048 KEYDBG(IPSEC_DATA, kdebug_secpolicy(sp)); 1049 1050 if (inp != NULL && inp->inp_sp != NULL && inp->inp_sp->sp_in == NULL) 1051 ipsec_cachepolicy(inp, sp, IPSEC_DIR_INBOUND); 1052 1053 /* Check policy. */ 1054 switch (sp->policy) { 1055 case IPSEC_POLICY_DISCARD: 1056 return (1); 1057 case IPSEC_POLICY_BYPASS: 1058 case IPSEC_POLICY_NONE: 1059 return (0); 1060 } 1061 1062 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1063 ("invalid policy %u", sp->policy)); 1064 1065 /* 1066 * ipsec[46]_common_input_cb after each transform adds 1067 * PACKET_TAG_IPSEC_IN_DONE mbuf tag. It contains SPI, proto, mode 1068 * and destination address from saidx. We can compare info from 1069 * these tags with requirements in SP. 1070 */ 1071 for (i = 0; i < sp->tcount; i++) { 1072 /* 1073 * Do not check IPcomp, since IPcomp document 1074 * says that we shouldn't compress small packets. 1075 * IPComp policy should always be treated as being 1076 * in "use" level. 1077 */ 1078 if (sp->req[i]->saidx.proto == IPPROTO_IPCOMP || 1079 ipsec_get_reqlevel(sp, i) != IPSEC_LEVEL_REQUIRE) 1080 continue; 1081 if (V_check_policy_history != 0 && 1082 ipsec_check_history(m, sp, i) != 0) 1083 return (1); 1084 else switch (sp->req[i]->saidx.proto) { 1085 case IPPROTO_ESP: 1086 if ((m->m_flags & M_DECRYPTED) == 0) { 1087 KEYDBG(IPSEC_DUMP, 1088 printf("%s: ESP m_flags:%x\n", __func__, 1089 m->m_flags)); 1090 return (1); 1091 } 1092 break; 1093 case IPPROTO_AH: 1094 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1095 KEYDBG(IPSEC_DUMP, 1096 printf("%s: AH m_flags:%x\n", __func__, 1097 m->m_flags)); 1098 return (1); 1099 } 1100 break; 1101 } 1102 } 1103 return (0); /* Valid. */ 1104 } 1105 1106 /* 1107 * Compute the byte size to be occupied by IPsec header. 1108 * In case it is tunnelled, it includes the size of outer IP header. 1109 */ 1110 size_t 1111 ipsec_hdrsiz_internal(struct secpolicy *sp) 1112 { 1113 size_t size; 1114 int i; 1115 1116 KEYDBG(IPSEC_STAMP, printf("%s: using SP(%p)\n", __func__, sp)); 1117 KEYDBG(IPSEC_DATA, kdebug_secpolicy(sp)); 1118 1119 switch (sp->policy) { 1120 case IPSEC_POLICY_DISCARD: 1121 case IPSEC_POLICY_BYPASS: 1122 case IPSEC_POLICY_NONE: 1123 return (0); 1124 } 1125 1126 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1127 ("invalid policy %u", sp->policy)); 1128 1129 /* 1130 * XXX: for each transform we need to lookup suitable SA 1131 * and use info from SA to calculate headers size. 1132 * XXX: for NAT-T we need to cosider UDP header size. 1133 */ 1134 size = 0; 1135 for (i = 0; i < sp->tcount; i++) { 1136 switch (sp->req[i]->saidx.proto) { 1137 case IPPROTO_ESP: 1138 size += esp_hdrsiz(NULL); 1139 break; 1140 case IPPROTO_AH: 1141 size += ah_hdrsiz(NULL); 1142 break; 1143 case IPPROTO_IPCOMP: 1144 size += sizeof(struct ipcomp); 1145 break; 1146 } 1147 1148 if (sp->req[i]->saidx.mode == IPSEC_MODE_TUNNEL) { 1149 switch (sp->req[i]->saidx.dst.sa.sa_family) { 1150 #ifdef INET 1151 case AF_INET: 1152 size += sizeof(struct ip); 1153 break; 1154 #endif 1155 #ifdef INET6 1156 case AF_INET6: 1157 size += sizeof(struct ip6_hdr); 1158 break; 1159 #endif 1160 default: 1161 ipseclog((LOG_ERR, "%s: unknown AF %d in " 1162 "IPsec tunnel SA\n", __func__, 1163 sp->req[i]->saidx.dst.sa.sa_family)); 1164 break; 1165 } 1166 } 1167 } 1168 return (size); 1169 } 1170 1171 /* 1172 * Compute ESP/AH header size for protocols with PCB, including 1173 * outer IP header. Currently only tcp_output() uses it. 1174 */ 1175 size_t 1176 ipsec_hdrsiz_inpcb(struct inpcb *inp) 1177 { 1178 struct secpolicyindex spidx; 1179 struct secpolicy *sp; 1180 size_t sz; 1181 1182 sp = ipsec_getpcbpolicy(inp, IPSEC_DIR_OUTBOUND); 1183 if (sp == NULL && key_havesp(IPSEC_DIR_OUTBOUND)) { 1184 ipsec_setspidx_inpcb(inp, &spidx, IPSEC_DIR_OUTBOUND); 1185 sp = key_allocsp(&spidx, IPSEC_DIR_OUTBOUND); 1186 } 1187 if (sp == NULL) 1188 sp = key_allocsp_default(); 1189 sz = ipsec_hdrsiz_internal(sp); 1190 key_freesp(&sp); 1191 return (sz); 1192 } 1193 1194 1195 #define IPSEC_BITMAP_INDEX_MASK(w) (w - 1) 1196 #define IPSEC_REDUNDANT_BIT_SHIFTS 5 1197 #define IPSEC_REDUNDANT_BITS (1 << IPSEC_REDUNDANT_BIT_SHIFTS) 1198 #define IPSEC_BITMAP_LOC_MASK (IPSEC_REDUNDANT_BITS - 1) 1199 1200 /* 1201 * Functions below are responsible for checking and updating bitmap. 1202 * These are used to separate ipsec_chkreplay() and ipsec_updatereplay() 1203 * from window implementation 1204 * 1205 * Based on RFC 6479. Blocks are 32 bits unsigned integers 1206 */ 1207 1208 static inline int 1209 check_window(const struct secreplay *replay, uint64_t seq) 1210 { 1211 int index, bit_location; 1212 1213 SECREPLAY_ASSERT(replay); 1214 1215 bit_location = seq & IPSEC_BITMAP_LOC_MASK; 1216 index = (seq >> IPSEC_REDUNDANT_BIT_SHIFTS) 1217 & IPSEC_BITMAP_INDEX_MASK(replay->bitmap_size); 1218 1219 /* This packet already seen? */ 1220 return ((replay->bitmap)[index] & (1 << bit_location)); 1221 } 1222 1223 static inline void 1224 advance_window(const struct secreplay *replay, uint64_t seq) 1225 { 1226 int i; 1227 uint64_t index, index_cur, diff; 1228 1229 SECREPLAY_ASSERT(replay); 1230 1231 index_cur = replay->last >> IPSEC_REDUNDANT_BIT_SHIFTS; 1232 index = seq >> IPSEC_REDUNDANT_BIT_SHIFTS; 1233 diff = index - index_cur; 1234 1235 if (diff > replay->bitmap_size) { 1236 /* something unusual in this case */ 1237 diff = replay->bitmap_size; 1238 } 1239 1240 for (i = 0; i < diff; i++) { 1241 replay->bitmap[(i + index_cur + 1) 1242 & IPSEC_BITMAP_INDEX_MASK(replay->bitmap_size)] = 0; 1243 } 1244 } 1245 1246 static inline void 1247 set_window(const struct secreplay *replay, uint64_t seq) 1248 { 1249 int index, bit_location; 1250 1251 SECREPLAY_ASSERT(replay); 1252 1253 bit_location = seq & IPSEC_BITMAP_LOC_MASK; 1254 index = (seq >> IPSEC_REDUNDANT_BIT_SHIFTS) 1255 & IPSEC_BITMAP_INDEX_MASK(replay->bitmap_size); 1256 1257 replay->bitmap[index] |= (1 << bit_location); 1258 } 1259 1260 /* 1261 * Check the variable replay window. 1262 * ipsec_chkreplay() performs replay check before ICV verification. 1263 * ipsec_updatereplay() updates replay bitmap. This must be called after 1264 * ICV verification (it also performs replay check, which is usually done 1265 * beforehand). 1266 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1267 * 1268 * Based on RFC 4303 1269 */ 1270 1271 int 1272 ipsec_chkreplay(uint32_t seq, uint32_t *seqhigh, struct secasvar *sav) 1273 { 1274 char buf[128]; 1275 struct secreplay *replay; 1276 uint32_t window; 1277 uint32_t tl, th, bl; 1278 uint32_t seqh; 1279 1280 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1281 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1282 1283 replay = sav->replay; 1284 1285 /* No need to check replay if disabled. */ 1286 if (replay->wsize == 0) { 1287 return (1); 1288 } 1289 1290 SECREPLAY_LOCK(replay); 1291 1292 /* Zero sequence number is not allowed. */ 1293 if (seq == 0 && replay->last == 0) { 1294 SECREPLAY_UNLOCK(replay); 1295 return (0); 1296 } 1297 1298 window = replay->wsize << 3; /* Size of window */ 1299 tl = (uint32_t)replay->last; /* Top of window, lower part */ 1300 th = (uint32_t)(replay->last >> 32); /* Top of window, high part */ 1301 bl = tl - window + 1; /* Bottom of window, lower part */ 1302 1303 /* 1304 * We keep the high part intact when: 1305 * 1) the seq is within [bl, 0xffffffff] and the whole window is 1306 * within one subspace; 1307 * 2) the seq is within [0, bl) and window spans two subspaces. 1308 */ 1309 if ((tl >= window - 1 && seq >= bl) || 1310 (tl < window - 1 && seq < bl)) { 1311 *seqhigh = th; 1312 if (seq <= tl) { 1313 /* Sequence number inside window - check against replay */ 1314 if (check_window(replay, seq)) { 1315 SECREPLAY_UNLOCK(replay); 1316 return (0); 1317 } 1318 } 1319 1320 SECREPLAY_UNLOCK(replay); 1321 /* Sequence number above top of window or not found in bitmap */ 1322 return (1); 1323 } 1324 1325 /* 1326 * If ESN is not enabled and packet with highest sequence number 1327 * was received we should report overflow 1328 */ 1329 if (tl == 0xffffffff && !(sav->flags & SADB_X_SAFLAGS_ESN)) { 1330 /* Set overflow flag. */ 1331 replay->overflow++; 1332 1333 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) { 1334 if (sav->sah->saidx.proto == IPPROTO_ESP) 1335 ESPSTAT_INC(esps_wrap); 1336 else if (sav->sah->saidx.proto == IPPROTO_AH) 1337 AHSTAT_INC(ahs_wrap); 1338 SECREPLAY_UNLOCK(replay); 1339 return (0); 1340 } 1341 1342 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1343 __func__, replay->overflow, 1344 ipsec_sa2str(sav, buf, sizeof(buf)))); 1345 } 1346 1347 /* 1348 * Seq is within [bl, 0xffffffff] and bl is within 1349 * [0xffffffff-window, 0xffffffff]. This means we got a seq 1350 * which is within our replay window, but in the previous 1351 * subspace. 1352 */ 1353 if (tl < window - 1 && seq >= bl) { 1354 if (th == 0) 1355 return (0); 1356 *seqhigh = th - 1; 1357 seqh = th - 1; 1358 if (check_window(replay, seq)) { 1359 SECREPLAY_UNLOCK(replay); 1360 return (0); 1361 } 1362 SECREPLAY_UNLOCK(replay); 1363 return (1); 1364 } 1365 1366 /* 1367 * Seq is within [0, bl) but the whole window is within one subspace. 1368 * This means that seq has wrapped and is in next subspace 1369 */ 1370 *seqhigh = th + 1; 1371 seqh = th + 1; 1372 1373 /* Don't let high part wrap. */ 1374 if (seqh == 0) { 1375 /* Set overflow flag. */ 1376 replay->overflow++; 1377 1378 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) { 1379 if (sav->sah->saidx.proto == IPPROTO_ESP) 1380 ESPSTAT_INC(esps_wrap); 1381 else if (sav->sah->saidx.proto == IPPROTO_AH) 1382 AHSTAT_INC(ahs_wrap); 1383 SECREPLAY_UNLOCK(replay); 1384 return (0); 1385 } 1386 1387 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1388 __func__, replay->overflow, 1389 ipsec_sa2str(sav, buf, sizeof(buf)))); 1390 } 1391 1392 SECREPLAY_UNLOCK(replay); 1393 return (1); 1394 } 1395 1396 /* 1397 * Check replay counter whether to update or not. 1398 * OUT: 0: OK 1399 * 1: NG 1400 */ 1401 int 1402 ipsec_updatereplay(uint32_t seq, struct secasvar *sav) 1403 { 1404 struct secreplay *replay; 1405 uint32_t window; 1406 uint32_t tl, th, bl; 1407 uint32_t seqh; 1408 1409 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1410 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1411 1412 replay = sav->replay; 1413 1414 /* No need to check replay if disabled. */ 1415 if (replay->wsize == 0) 1416 return (0); 1417 1418 SECREPLAY_LOCK(replay); 1419 1420 /* Zero sequence number is not allowed. */ 1421 if (seq == 0 && replay->last == 0) { 1422 SECREPLAY_UNLOCK(replay); 1423 return (1); 1424 } 1425 1426 window = replay->wsize << 3; /* Size of window */ 1427 tl = (uint32_t)replay->last; /* Top of window, lower part */ 1428 th = (uint32_t)(replay->last >> 32); /* Top of window, high part */ 1429 bl = tl - window + 1; /* Bottom of window, lower part */ 1430 1431 /* 1432 * We keep the high part intact when: 1433 * 1) the seq is within [bl, 0xffffffff] and the whole window is 1434 * within one subspace; 1435 * 2) the seq is within [0, bl) and window spans two subspaces. 1436 */ 1437 if ((tl >= window - 1 && seq >= bl) || 1438 (tl < window - 1 && seq < bl)) { 1439 seqh = th; 1440 if (seq <= tl) { 1441 /* Sequence number inside window - check against replay */ 1442 if (check_window(replay, seq)) { 1443 SECREPLAY_UNLOCK(replay); 1444 return (1); 1445 } 1446 set_window(replay, seq); 1447 } else { 1448 advance_window(replay, ((uint64_t)seqh << 32) | seq); 1449 set_window(replay, seq); 1450 replay->last = ((uint64_t)seqh << 32) | seq; 1451 } 1452 1453 /* Sequence number above top of window or not found in bitmap */ 1454 replay->count++; 1455 SECREPLAY_UNLOCK(replay); 1456 return (0); 1457 } 1458 1459 if (!(sav->flags & SADB_X_SAFLAGS_ESN)) { 1460 SECREPLAY_UNLOCK(replay); 1461 return (1); 1462 } 1463 1464 /* 1465 * Seq is within [bl, 0xffffffff] and bl is within 1466 * [0xffffffff-window, 0xffffffff]. This means we got a seq 1467 * which is within our replay window, but in the previous 1468 * subspace. 1469 */ 1470 if (tl < window - 1 && seq >= bl) { 1471 if (th == 0) { 1472 SECREPLAY_UNLOCK(replay); 1473 return (1); 1474 } 1475 if (check_window(replay, seq)) { 1476 SECREPLAY_UNLOCK(replay); 1477 return (1); 1478 } 1479 1480 set_window(replay, seq); 1481 replay->count++; 1482 SECREPLAY_UNLOCK(replay); 1483 return (0); 1484 } 1485 1486 /* 1487 * Seq is within [0, bl) but the whole window is within one subspace. 1488 * This means that seq has wrapped and is in next subspace 1489 */ 1490 seqh = th + 1; 1491 1492 /* Don't let high part wrap. */ 1493 if (seqh == 0) { 1494 SECREPLAY_UNLOCK(replay); 1495 return (1); 1496 } 1497 1498 advance_window(replay, ((uint64_t)seqh << 32) | seq); 1499 set_window(replay, seq); 1500 replay->last = ((uint64_t)seqh << 32) | seq; 1501 replay->count++; 1502 1503 SECREPLAY_UNLOCK(replay); 1504 return (0); 1505 } 1506 int 1507 ipsec_updateid(struct secasvar *sav, crypto_session_t *new, 1508 crypto_session_t *old) 1509 { 1510 crypto_session_t tmp; 1511 1512 /* 1513 * tdb_cryptoid is initialized by xform_init(). 1514 * Then it can be changed only when some crypto error occurred or 1515 * when SA is deleted. We stored used cryptoid in the xform_data 1516 * structure. In case when crypto error occurred and crypto 1517 * subsystem has reinited the session, it returns new cryptoid 1518 * and EAGAIN error code. 1519 * 1520 * This function will be called when we got EAGAIN from crypto 1521 * subsystem. 1522 * *new is cryptoid that was returned by crypto subsystem in 1523 * the crp_sid. 1524 * *old is the original cryptoid that we stored in xform_data. 1525 * 1526 * For first failed request *old == sav->tdb_cryptoid, then 1527 * we update sav->tdb_cryptoid and redo crypto_dispatch(). 1528 * For next failed request *old != sav->tdb_cryptoid, then 1529 * we store cryptoid from first request into the *new variable 1530 * and crp_sid from this second session will be returned via 1531 * *old pointer, so caller can release second session. 1532 * 1533 * XXXAE: check this more carefully. 1534 */ 1535 KEYDBG(IPSEC_STAMP, 1536 printf("%s: SA(%p) moves cryptoid %p -> %p\n", 1537 __func__, sav, *old, *new)); 1538 KEYDBG(IPSEC_DATA, kdebug_secasv(sav)); 1539 SECASVAR_WLOCK(sav); 1540 if (sav->tdb_cryptoid != *old) { 1541 /* cryptoid was already updated */ 1542 tmp = *new; 1543 *new = sav->tdb_cryptoid; 1544 *old = tmp; 1545 SECASVAR_WUNLOCK(sav); 1546 return (1); 1547 } 1548 sav->tdb_cryptoid = *new; 1549 SECASVAR_WUNLOCK(sav); 1550 return (0); 1551 } 1552 1553 int 1554 ipsec_initialized(void) 1555 { 1556 1557 return (V_def_policy != NULL); 1558 } 1559 1560 static void 1561 def_policy_init(const void *unused __unused) 1562 { 1563 1564 V_def_policy = key_newsp(); 1565 if (V_def_policy != NULL) { 1566 V_def_policy->policy = IPSEC_POLICY_NONE; 1567 /* Force INPCB SP cache invalidation */ 1568 key_bumpspgen(); 1569 } else 1570 printf("%s: failed to initialize default policy\n", __func__); 1571 } 1572 1573 static void 1574 def_policy_uninit(const void *unused __unused) 1575 { 1576 1577 if (V_def_policy != NULL) { 1578 key_freesp(&V_def_policy); 1579 key_bumpspgen(); 1580 } 1581 } 1582 1583 VNET_SYSINIT(def_policy_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST, 1584 def_policy_init, NULL); 1585 VNET_SYSUNINIT(def_policy_uninit, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST, 1586 def_policy_uninit, NULL); 1587