1 /* $FreeBSD$ */ 2 /* $KAME: ipsec.c,v 1.103 2001/05/24 07:14:18 sakane Exp $ */ 3 4 /*- 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * IPsec controller part. 35 */ 36 37 #include "opt_inet.h" 38 #include "opt_inet6.h" 39 #include "opt_ipsec.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/malloc.h> 44 #include <sys/mbuf.h> 45 #include <sys/domain.h> 46 #include <sys/priv.h> 47 #include <sys/protosw.h> 48 #include <sys/socket.h> 49 #include <sys/socketvar.h> 50 #include <sys/errno.h> 51 #include <sys/time.h> 52 #include <sys/kernel.h> 53 #include <sys/syslog.h> 54 #include <sys/sysctl.h> 55 #include <sys/proc.h> 56 #include <sys/vimage.h> 57 58 #include <net/if.h> 59 #include <net/route.h> 60 61 #include <netinet/in.h> 62 #include <netinet/in_systm.h> 63 #include <netinet/ip.h> 64 #include <netinet/ip_var.h> 65 #include <netinet/in_var.h> 66 #include <netinet/udp.h> 67 #include <netinet/udp_var.h> 68 #include <netinet/tcp.h> 69 #include <netinet/udp.h> 70 71 #include <netinet/ip6.h> 72 #ifdef INET6 73 #include <netinet6/ip6_var.h> 74 #endif 75 #include <netinet/in_pcb.h> 76 #ifdef INET6 77 #include <netinet/icmp6.h> 78 #endif 79 80 #include <sys/types.h> 81 #include <netipsec/ipsec.h> 82 #ifdef INET6 83 #include <netipsec/ipsec6.h> 84 #endif 85 #include <netipsec/ah_var.h> 86 #include <netipsec/esp_var.h> 87 #include <netipsec/ipcomp.h> /*XXX*/ 88 #include <netipsec/ipcomp_var.h> 89 90 #include <netipsec/key.h> 91 #include <netipsec/keydb.h> 92 #include <netipsec/key_debug.h> 93 94 #include <netipsec/xform.h> 95 96 #include <machine/in_cksum.h> 97 98 #include <opencrypto/cryptodev.h> 99 100 #ifndef VIMAGE 101 #ifndef VIMAGE_GLOBALS 102 struct vnet_ipsec vnet_ipsec_0; 103 #endif 104 #endif 105 106 #ifdef VIMAGE_GLOBALS 107 /* NB: name changed so netstat doesn't use it. */ 108 struct ipsecstat ipsec4stat; 109 struct secpolicy ip4_def_policy; 110 int ipsec_debug; 111 int ip4_ah_offsetmask; 112 int ip4_ipsec_dfbit; 113 int ip4_esp_trans_deflev; 114 int ip4_esp_net_deflev; 115 int ip4_ah_trans_deflev; 116 int ip4_ah_net_deflev; 117 int ip4_ipsec_ecn; 118 int ip4_esp_randpad; 119 /* 120 * Crypto support requirements: 121 * 122 * 1 require hardware support 123 * -1 require software support 124 * 0 take anything 125 */ 126 int crypto_support; 127 #endif /* VIMAGE_GLOBALS */ 128 129 SYSCTL_DECL(_net_inet_ipsec); 130 131 /* net.inet.ipsec */ 132 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_POLICY, 133 def_policy, CTLFLAG_RW, ip4_def_policy.policy, 0, 134 "IPsec default policy."); 135 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, 136 esp_trans_deflev, CTLFLAG_RW, ip4_esp_trans_deflev, 0, 137 "Default ESP transport mode level"); 138 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, 139 esp_net_deflev, CTLFLAG_RW, ip4_esp_net_deflev, 0, 140 "Default ESP tunnel mode level."); 141 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, 142 ah_trans_deflev, CTLFLAG_RW, ip4_ah_trans_deflev, 0, 143 "AH transfer mode default level."); 144 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, 145 ah_net_deflev, CTLFLAG_RW, ip4_ah_net_deflev, 0, 146 "AH tunnel mode default level."); 147 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_AH_CLEARTOS, 148 ah_cleartos, CTLFLAG_RW, ah_cleartos, 0, 149 "If set clear type-of-service field when doing AH computation."); 150 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, 151 ah_offsetmask, CTLFLAG_RW, ip4_ah_offsetmask, 0, 152 "If not set clear offset field mask when doing AH computation."); 153 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DFBIT, 154 dfbit, CTLFLAG_RW, ip4_ipsec_dfbit, 0, 155 "Do not fragment bit on encap."); 156 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_ECN, 157 ecn, CTLFLAG_RW, ip4_ipsec_ecn, 0, 158 "Explicit Congestion Notification handling."); 159 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEBUG, 160 debug, CTLFLAG_RW, ipsec_debug, 0, 161 "Enable IPsec debugging output when set."); 162 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, OID_AUTO, 163 crypto_support, CTLFLAG_RW, crypto_support,0, 164 "Crypto driver selection."); 165 SYSCTL_V_STRUCT(V_NET, vnet_ipsec, _net_inet_ipsec, OID_AUTO, 166 ipsecstats, CTLFLAG_RD, ipsec4stat, ipsecstat, 167 "IPsec IPv4 statistics."); 168 169 #ifdef REGRESSION 170 #ifdef VIMAGE_GLOBALS 171 int ipsec_replay; 172 int ipsec_integrity; 173 #endif 174 /* 175 * When set to 1, IPsec will send packets with the same sequence number. 176 * This allows to verify if the other side has proper replay attacks detection. 177 */ 178 SYSCTL_V_INT(V_NET, vnet_ipsec,_net_inet_ipsec, OID_AUTO, test_replay, 179 CTLFLAG_RW, ipsec_replay, 0, "Emulate replay attack"); 180 /* 181 * When set 1, IPsec will send packets with corrupted HMAC. 182 * This allows to verify if the other side properly detects modified packets. 183 */ 184 SYSCTL_V_INT(V_NET, vnet_ipsec,_net_inet_ipsec, OID_AUTO, test_integrity, 185 CTLFLAG_RW, ipsec_integrity, 0, "Emulate man-in-the-middle attack"); 186 #endif 187 188 #ifdef INET6 189 #ifdef VIMAGE_GLOBALS 190 struct ipsecstat ipsec6stat; 191 int ip6_esp_trans_deflev; 192 int ip6_esp_net_deflev; 193 int ip6_ah_trans_deflev; 194 int ip6_ah_net_deflev; 195 int ip6_ipsec_ecn; 196 #endif 197 198 SYSCTL_DECL(_net_inet6_ipsec6); 199 200 /* net.inet6.ipsec6 */ 201 #ifdef COMPAT_KAME 202 SYSCTL_OID(_net_inet6_ipsec6, IPSECCTL_STATS, stats, CTLFLAG_RD, 203 0, 0, compat_ipsecstats_sysctl, "S", "IPsec IPv6 statistics."); 204 #endif /* COMPAT_KAME */ 205 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_POLICY, 206 def_policy, CTLFLAG_RW, ip4_def_policy.policy, 0, 207 "IPsec default policy."); 208 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV, 209 esp_trans_deflev, CTLFLAG_RW, ip6_esp_trans_deflev, 0, 210 "Default ESP transport mode level."); 211 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV, 212 esp_net_deflev, CTLFLAG_RW, ip6_esp_net_deflev, 0, 213 "Default ESP tunnel mode level."); 214 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV, 215 ah_trans_deflev, CTLFLAG_RW, ip6_ah_trans_deflev, 0, 216 "AH transfer mode default level."); 217 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV, 218 ah_net_deflev, CTLFLAG_RW, ip6_ah_net_deflev, 0, 219 "AH tunnel mode default level."); 220 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_ECN, 221 ecn, CTLFLAG_RW, ip6_ipsec_ecn, 0, 222 "Explicit Congestion Notification handling."); 223 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEBUG, 224 debug, CTLFLAG_RW, ipsec_debug, 0, 225 "Enable IPsec debugging output when set."); 226 SYSCTL_V_STRUCT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_STATS, 227 ipsecstats, CTLFLAG_RD, ipsec6stat, ipsecstat, 228 "IPsec IPv6 statistics."); 229 #endif /* INET6 */ 230 231 static int ipsec_setspidx_inpcb __P((struct mbuf *, struct inpcb *)); 232 static int ipsec_setspidx __P((struct mbuf *, struct secpolicyindex *, int)); 233 static void ipsec4_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 234 static int ipsec4_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 235 #ifdef INET6 236 static void ipsec6_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 237 static int ipsec6_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 238 #endif 239 static void ipsec_delpcbpolicy __P((struct inpcbpolicy *)); 240 static struct secpolicy *ipsec_deepcopy_policy __P((struct secpolicy *src)); 241 static void vshiftl __P((unsigned char *, int, int)); 242 243 MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy"); 244 245 void 246 ipsec_init(void) 247 { 248 INIT_VNET_IPSEC(curvnet); 249 250 #ifdef IPSEC_DEBUG 251 V_ipsec_debug = 1; 252 #else 253 V_ipsec_debug = 0; 254 #endif 255 256 V_ip4_ah_offsetmask = 0; /* maybe IP_DF? */ 257 V_ip4_ipsec_dfbit = 0; /* DF bit on encap. 0: clear 1: set 2: copy */ 258 V_ip4_esp_trans_deflev = IPSEC_LEVEL_USE; 259 V_ip4_esp_net_deflev = IPSEC_LEVEL_USE; 260 V_ip4_ah_trans_deflev = IPSEC_LEVEL_USE; 261 V_ip4_ah_net_deflev = IPSEC_LEVEL_USE; 262 V_ip4_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 263 V_ip4_esp_randpad = -1; 264 265 V_crypto_support = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE; 266 267 #ifdef REGRESSION 268 V_ipsec_replay = 0; 269 V_ipsec_integrity = 0; 270 #endif 271 272 #ifdef INET6 273 V_ip6_esp_trans_deflev = IPSEC_LEVEL_USE; 274 V_ip6_esp_net_deflev = IPSEC_LEVEL_USE; 275 V_ip6_ah_trans_deflev = IPSEC_LEVEL_USE; 276 V_ip6_ah_net_deflev = IPSEC_LEVEL_USE; 277 V_ip6_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 278 #endif 279 } 280 281 /* 282 * Return a held reference to the default SP. 283 */ 284 static struct secpolicy * 285 key_allocsp_default(const char* where, int tag) 286 { 287 INIT_VNET_IPSEC(curvnet); 288 struct secpolicy *sp; 289 290 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 291 printf("DP key_allocsp_default from %s:%u\n", where, tag)); 292 293 sp = &V_ip4_def_policy; 294 if (sp->policy != IPSEC_POLICY_DISCARD && 295 sp->policy != IPSEC_POLICY_NONE) { 296 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n", 297 sp->policy, IPSEC_POLICY_NONE)); 298 sp->policy = IPSEC_POLICY_NONE; 299 } 300 key_addref(sp); 301 302 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 303 printf("DP key_allocsp_default returns SP:%p (%u)\n", 304 sp, sp->refcnt)); 305 return (sp); 306 } 307 #define KEY_ALLOCSP_DEFAULT() \ 308 key_allocsp_default(__FILE__, __LINE__) 309 310 /* 311 * For OUTBOUND packet having a socket. Searching SPD for packet, 312 * and return a pointer to SP. 313 * OUT: NULL: no apropreate SP found, the following value is set to error. 314 * 0 : bypass 315 * EACCES : discard packet. 316 * ENOENT : ipsec_acquire() in progress, maybe. 317 * others : error occured. 318 * others: a pointer to SP 319 * 320 * NOTE: IPv6 mapped adddress concern is implemented here. 321 */ 322 struct secpolicy * 323 ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir) 324 { 325 struct secpolicy *sp; 326 327 IPSEC_ASSERT(tdbi != NULL, ("null tdbi")); 328 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 329 ("invalid direction %u", dir)); 330 331 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir); 332 if (sp == NULL) /*XXX????*/ 333 sp = KEY_ALLOCSP_DEFAULT(); 334 IPSEC_ASSERT(sp != NULL, ("null SP")); 335 return (sp); 336 } 337 338 /* 339 * For OUTBOUND packet having a socket. Searching SPD for packet, 340 * and return a pointer to SP. 341 * OUT: NULL: no apropreate SP found, the following value is set to error. 342 * 0 : bypass 343 * EACCES : discard packet. 344 * ENOENT : ipsec_acquire() in progress, maybe. 345 * others : error occured. 346 * others: a pointer to SP 347 * 348 * NOTE: IPv6 mapped adddress concern is implemented here. 349 */ 350 static struct secpolicy * 351 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb *inp, int *error) 352 { 353 INIT_VNET_IPSEC(curvnet); 354 struct inpcbpolicy *pcbsp; 355 struct secpolicy *currsp = NULL; /* Policy on socket. */ 356 struct secpolicy *sp; 357 358 IPSEC_ASSERT(m != NULL, ("null mbuf")); 359 IPSEC_ASSERT(inp != NULL, ("null inpcb")); 360 IPSEC_ASSERT(error != NULL, ("null error")); 361 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 362 ("invalid direction %u", dir)); 363 364 /* Set spidx in pcb. */ 365 *error = ipsec_setspidx_inpcb(m, inp); 366 if (*error) 367 return (NULL); 368 369 pcbsp = inp->inp_sp; 370 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp")); 371 switch (dir) { 372 case IPSEC_DIR_INBOUND: 373 currsp = pcbsp->sp_in; 374 break; 375 case IPSEC_DIR_OUTBOUND: 376 currsp = pcbsp->sp_out; 377 break; 378 } 379 IPSEC_ASSERT(currsp != NULL, ("null currsp")); 380 381 if (pcbsp->priv) { /* When privilieged socket. */ 382 switch (currsp->policy) { 383 case IPSEC_POLICY_BYPASS: 384 case IPSEC_POLICY_IPSEC: 385 key_addref(currsp); 386 sp = currsp; 387 break; 388 389 case IPSEC_POLICY_ENTRUST: 390 /* Look for a policy in SPD. */ 391 sp = KEY_ALLOCSP(&currsp->spidx, dir); 392 if (sp == NULL) /* No SP found. */ 393 sp = KEY_ALLOCSP_DEFAULT(); 394 break; 395 396 default: 397 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n", 398 __func__, currsp->policy)); 399 *error = EINVAL; 400 return (NULL); 401 } 402 } else { /* Unpriv, SPD has policy. */ 403 sp = KEY_ALLOCSP(&currsp->spidx, dir); 404 if (sp == NULL) { /* No SP found. */ 405 switch (currsp->policy) { 406 case IPSEC_POLICY_BYPASS: 407 ipseclog((LOG_ERR, "%s: Illegal policy for " 408 "non-priviliged defined %d\n", 409 __func__, currsp->policy)); 410 *error = EINVAL; 411 return (NULL); 412 413 case IPSEC_POLICY_ENTRUST: 414 sp = KEY_ALLOCSP_DEFAULT(); 415 break; 416 417 case IPSEC_POLICY_IPSEC: 418 key_addref(currsp); 419 sp = currsp; 420 break; 421 422 default: 423 ipseclog((LOG_ERR, "%s: Invalid policy for " 424 "PCB %d\n", __func__, currsp->policy)); 425 *error = EINVAL; 426 return (NULL); 427 } 428 } 429 } 430 IPSEC_ASSERT(sp != NULL, 431 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy)); 432 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 433 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n", 434 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt)); 435 return (sp); 436 } 437 438 /* 439 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 440 * and return a pointer to SP. 441 * OUT: positive: a pointer to the entry for security policy leaf matched. 442 * NULL: no apropreate SP found, the following value is set to error. 443 * 0 : bypass 444 * EACCES : discard packet. 445 * ENOENT : ipsec_acquire() in progress, maybe. 446 * others : error occured. 447 */ 448 struct secpolicy * 449 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 450 { 451 INIT_VNET_IPSEC(curvnet); 452 struct secpolicyindex spidx; 453 struct secpolicy *sp; 454 455 IPSEC_ASSERT(m != NULL, ("null mbuf")); 456 IPSEC_ASSERT(error != NULL, ("null error")); 457 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 458 ("invalid direction %u", dir)); 459 460 sp = NULL; 461 if (key_havesp(dir)) { 462 /* Make an index to look for a policy. */ 463 *error = ipsec_setspidx(m, &spidx, 464 (flag & IP_FORWARDING) ? 0 : 1); 465 if (*error != 0) { 466 DPRINTF(("%s: setpidx failed, dir %u flag %u\n", 467 __func__, dir, flag)); 468 return (NULL); 469 } 470 spidx.dir = dir; 471 472 sp = KEY_ALLOCSP(&spidx, dir); 473 } 474 if (sp == NULL) /* No SP found, use system default. */ 475 sp = KEY_ALLOCSP_DEFAULT(); 476 IPSEC_ASSERT(sp != NULL, ("null SP")); 477 return (sp); 478 } 479 480 struct secpolicy * 481 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 482 struct inpcb *inp) 483 { 484 INIT_VNET_IPSEC(curvnet); 485 struct secpolicy *sp; 486 487 *error = 0; 488 if (inp == NULL) 489 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 490 else 491 sp = ipsec_getpolicybysock(m, dir, inp, error); 492 if (sp == NULL) { 493 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error")); 494 V_ipsec4stat.ips_out_inval++; 495 return (NULL); 496 } 497 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error)); 498 switch (sp->policy) { 499 case IPSEC_POLICY_ENTRUST: 500 default: 501 printf("%s: invalid policy %u\n", __func__, sp->policy); 502 /* FALLTHROUGH */ 503 case IPSEC_POLICY_DISCARD: 504 V_ipsec4stat.ips_out_polvio++; 505 *error = -EINVAL; /* Packet is discarded by caller. */ 506 break; 507 case IPSEC_POLICY_BYPASS: 508 case IPSEC_POLICY_NONE: 509 KEY_FREESP(&sp); 510 sp = NULL; /* NB: force NULL result. */ 511 break; 512 case IPSEC_POLICY_IPSEC: 513 if (sp->req == NULL) /* Acquire a SA. */ 514 *error = key_spdacquire(sp); 515 break; 516 } 517 if (*error != 0) { 518 KEY_FREESP(&sp); 519 sp = NULL; 520 } 521 return (sp); 522 } 523 524 static int 525 ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp) 526 { 527 int error; 528 529 IPSEC_ASSERT(inp != NULL, ("null inp")); 530 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 531 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL, 532 ("null sp_in || sp_out")); 533 534 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1); 535 if (error == 0) { 536 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 537 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx; 538 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 539 } else { 540 bzero(&inp->inp_sp->sp_in->spidx, 541 sizeof (inp->inp_sp->sp_in->spidx)); 542 bzero(&inp->inp_sp->sp_out->spidx, 543 sizeof (inp->inp_sp->sp_in->spidx)); 544 } 545 return (error); 546 } 547 548 /* 549 * Configure security policy index (src/dst/proto/sport/dport) 550 * by looking at the content of mbuf. 551 * The caller is responsible for error recovery (like clearing up spidx). 552 */ 553 static int 554 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 555 { 556 INIT_VNET_IPSEC(curvnet); 557 struct ip *ip = NULL; 558 struct ip ipbuf; 559 u_int v; 560 struct mbuf *n; 561 int len; 562 int error; 563 564 IPSEC_ASSERT(m != NULL, ("null mbuf")); 565 566 /* 567 * Validate m->m_pkthdr.len. We see incorrect length if we 568 * mistakenly call this function with inconsistent mbuf chain 569 * (like 4.4BSD tcp/udp processing). XXX Should we panic here? 570 */ 571 len = 0; 572 for (n = m; n; n = n->m_next) 573 len += n->m_len; 574 if (m->m_pkthdr.len != len) { 575 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 576 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n", 577 __func__, len, m->m_pkthdr.len)); 578 return (EINVAL); 579 } 580 581 if (m->m_pkthdr.len < sizeof(struct ip)) { 582 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 583 printf("%s: pkthdr len(%d) too small (v4), ignored.\n", 584 __func__, m->m_pkthdr.len)); 585 return (EINVAL); 586 } 587 588 if (m->m_len >= sizeof(*ip)) 589 ip = mtod(m, struct ip *); 590 else { 591 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf); 592 ip = &ipbuf; 593 } 594 #ifdef _IP_VHL 595 v = _IP_VHL_V(ip->ip_vhl); 596 #else 597 v = ip->ip_v; 598 #endif 599 switch (v) { 600 case 4: 601 error = ipsec4_setspidx_ipaddr(m, spidx); 602 if (error) 603 return (error); 604 ipsec4_get_ulp(m, spidx, needport); 605 return (0); 606 #ifdef INET6 607 case 6: 608 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 609 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 610 printf("%s: pkthdr len(%d) too small (v6), " 611 "ignored\n", __func__, m->m_pkthdr.len)); 612 return (EINVAL); 613 } 614 error = ipsec6_setspidx_ipaddr(m, spidx); 615 if (error) 616 return (error); 617 ipsec6_get_ulp(m, spidx, needport); 618 return (0); 619 #endif 620 default: 621 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 622 printf("%s: " "unknown IP version %u, ignored.\n", 623 __func__, v)); 624 return (EINVAL); 625 } 626 } 627 628 static void 629 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 630 { 631 u_int8_t nxt; 632 int off; 633 634 /* Sanity check. */ 635 IPSEC_ASSERT(m != NULL, ("null mbuf")); 636 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short")); 637 638 /* NB: ip_input() flips it into host endian. XXX Need more checking. */ 639 if (m->m_len < sizeof (struct ip)) { 640 struct ip *ip = mtod(m, struct ip *); 641 if (ip->ip_off & (IP_MF | IP_OFFMASK)) 642 goto done; 643 #ifdef _IP_VHL 644 off = _IP_VHL_HL(ip->ip_vhl) << 2; 645 #else 646 off = ip->ip_hl << 2; 647 #endif 648 nxt = ip->ip_p; 649 } else { 650 struct ip ih; 651 652 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih); 653 if (ih.ip_off & (IP_MF | IP_OFFMASK)) 654 goto done; 655 #ifdef _IP_VHL 656 off = _IP_VHL_HL(ih.ip_vhl) << 2; 657 #else 658 off = ih.ip_hl << 2; 659 #endif 660 nxt = ih.ip_p; 661 } 662 663 while (off < m->m_pkthdr.len) { 664 struct ip6_ext ip6e; 665 struct tcphdr th; 666 struct udphdr uh; 667 668 switch (nxt) { 669 case IPPROTO_TCP: 670 spidx->ul_proto = nxt; 671 if (!needport) 672 goto done_proto; 673 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 674 goto done; 675 m_copydata(m, off, sizeof (th), (caddr_t) &th); 676 spidx->src.sin.sin_port = th.th_sport; 677 spidx->dst.sin.sin_port = th.th_dport; 678 return; 679 case IPPROTO_UDP: 680 spidx->ul_proto = nxt; 681 if (!needport) 682 goto done_proto; 683 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 684 goto done; 685 m_copydata(m, off, sizeof (uh), (caddr_t) &uh); 686 spidx->src.sin.sin_port = uh.uh_sport; 687 spidx->dst.sin.sin_port = uh.uh_dport; 688 return; 689 case IPPROTO_AH: 690 if (off + sizeof(ip6e) > m->m_pkthdr.len) 691 goto done; 692 /* XXX Sigh, this works but is totally bogus. */ 693 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e); 694 off += (ip6e.ip6e_len + 2) << 2; 695 nxt = ip6e.ip6e_nxt; 696 break; 697 case IPPROTO_ICMP: 698 default: 699 /* XXX Intermediate headers??? */ 700 spidx->ul_proto = nxt; 701 goto done_proto; 702 } 703 } 704 done: 705 spidx->ul_proto = IPSEC_ULPROTO_ANY; 706 done_proto: 707 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 708 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 709 } 710 711 /* Assumes that m is sane. */ 712 static int 713 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 714 { 715 static const struct sockaddr_in template = { 716 sizeof (struct sockaddr_in), 717 AF_INET, 718 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 719 }; 720 721 spidx->src.sin = template; 722 spidx->dst.sin = template; 723 724 if (m->m_len < sizeof (struct ip)) { 725 m_copydata(m, offsetof(struct ip, ip_src), 726 sizeof (struct in_addr), 727 (caddr_t) &spidx->src.sin.sin_addr); 728 m_copydata(m, offsetof(struct ip, ip_dst), 729 sizeof (struct in_addr), 730 (caddr_t) &spidx->dst.sin.sin_addr); 731 } else { 732 struct ip *ip = mtod(m, struct ip *); 733 spidx->src.sin.sin_addr = ip->ip_src; 734 spidx->dst.sin.sin_addr = ip->ip_dst; 735 } 736 737 spidx->prefs = sizeof(struct in_addr) << 3; 738 spidx->prefd = sizeof(struct in_addr) << 3; 739 740 return (0); 741 } 742 743 #ifdef INET6 744 static void 745 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 746 { 747 INIT_VNET_IPSEC(curvnet); 748 int off, nxt; 749 struct tcphdr th; 750 struct udphdr uh; 751 struct icmp6_hdr ih; 752 753 /* Sanity check. */ 754 if (m == NULL) 755 panic("%s: NULL pointer was passed.\n", __func__); 756 757 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 758 printf("%s:\n", __func__); kdebug_mbuf(m)); 759 760 /* Set default. */ 761 spidx->ul_proto = IPSEC_ULPROTO_ANY; 762 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 763 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 764 765 nxt = -1; 766 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 767 if (off < 0 || m->m_pkthdr.len < off) 768 return; 769 770 switch (nxt) { 771 case IPPROTO_TCP: 772 spidx->ul_proto = nxt; 773 if (!needport) 774 break; 775 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 776 break; 777 m_copydata(m, off, sizeof(th), (caddr_t)&th); 778 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 779 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 780 break; 781 case IPPROTO_UDP: 782 spidx->ul_proto = nxt; 783 if (!needport) 784 break; 785 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 786 break; 787 m_copydata(m, off, sizeof(uh), (caddr_t)&uh); 788 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 789 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 790 break; 791 case IPPROTO_ICMPV6: 792 spidx->ul_proto = nxt; 793 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 794 break; 795 m_copydata(m, off, sizeof(ih), (caddr_t)&ih); 796 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 797 htons((uint16_t)ih.icmp6_type); 798 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 799 htons((uint16_t)ih.icmp6_code); 800 break; 801 default: 802 /* XXX Intermediate headers??? */ 803 spidx->ul_proto = nxt; 804 break; 805 } 806 } 807 808 /* Assumes that m is sane. */ 809 static int 810 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 811 { 812 struct ip6_hdr *ip6 = NULL; 813 struct ip6_hdr ip6buf; 814 struct sockaddr_in6 *sin6; 815 816 if (m->m_len >= sizeof(*ip6)) 817 ip6 = mtod(m, struct ip6_hdr *); 818 else { 819 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf); 820 ip6 = &ip6buf; 821 } 822 823 sin6 = (struct sockaddr_in6 *)&spidx->src; 824 bzero(sin6, sizeof(*sin6)); 825 sin6->sin6_family = AF_INET6; 826 sin6->sin6_len = sizeof(struct sockaddr_in6); 827 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src)); 828 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 829 sin6->sin6_addr.s6_addr16[1] = 0; 830 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 831 } 832 spidx->prefs = sizeof(struct in6_addr) << 3; 833 834 sin6 = (struct sockaddr_in6 *)&spidx->dst; 835 bzero(sin6, sizeof(*sin6)); 836 sin6->sin6_family = AF_INET6; 837 sin6->sin6_len = sizeof(struct sockaddr_in6); 838 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst)); 839 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 840 sin6->sin6_addr.s6_addr16[1] = 0; 841 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 842 } 843 spidx->prefd = sizeof(struct in6_addr) << 3; 844 845 return (0); 846 } 847 #endif 848 849 static void 850 ipsec_delpcbpolicy(struct inpcbpolicy *p) 851 { 852 853 free(p, M_IPSEC_INPCB); 854 } 855 856 /* Initialize policy in PCB. */ 857 int 858 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp) 859 { 860 INIT_VNET_IPSEC(curvnet); 861 struct inpcbpolicy *new; 862 863 /* Sanity check. */ 864 if (so == NULL || pcb_sp == NULL) 865 panic("%s: NULL pointer was passed.\n", __func__); 866 867 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy), 868 M_IPSEC_INPCB, M_NOWAIT|M_ZERO); 869 if (new == NULL) { 870 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 871 return (ENOBUFS); 872 } 873 874 new->priv = IPSEC_IS_PRIVILEGED_SO(so); 875 876 if ((new->sp_in = KEY_NEWSP()) == NULL) { 877 ipsec_delpcbpolicy(new); 878 return (ENOBUFS); 879 } 880 new->sp_in->state = IPSEC_SPSTATE_ALIVE; 881 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 882 883 if ((new->sp_out = KEY_NEWSP()) == NULL) { 884 KEY_FREESP(&new->sp_in); 885 ipsec_delpcbpolicy(new); 886 return (ENOBUFS); 887 } 888 new->sp_out->state = IPSEC_SPSTATE_ALIVE; 889 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 890 891 *pcb_sp = new; 892 893 return (0); 894 } 895 896 /* Copy old IPsec policy into new. */ 897 int 898 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new) 899 { 900 struct secpolicy *sp; 901 902 sp = ipsec_deepcopy_policy(old->sp_in); 903 if (sp) { 904 KEY_FREESP(&new->sp_in); 905 new->sp_in = sp; 906 } else 907 return (ENOBUFS); 908 909 sp = ipsec_deepcopy_policy(old->sp_out); 910 if (sp) { 911 KEY_FREESP(&new->sp_out); 912 new->sp_out = sp; 913 } else 914 return (ENOBUFS); 915 916 new->priv = old->priv; 917 918 return (0); 919 } 920 921 struct ipsecrequest * 922 ipsec_newisr(void) 923 { 924 struct ipsecrequest *p; 925 926 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO); 927 if (p != NULL) 928 IPSECREQUEST_LOCK_INIT(p); 929 return (p); 930 } 931 932 void 933 ipsec_delisr(struct ipsecrequest *p) 934 { 935 936 IPSECREQUEST_LOCK_DESTROY(p); 937 free(p, M_IPSEC_SR); 938 } 939 940 /* Deep-copy a policy in PCB. */ 941 static struct secpolicy * 942 ipsec_deepcopy_policy(struct secpolicy *src) 943 { 944 struct ipsecrequest *newchain = NULL; 945 struct ipsecrequest *p; 946 struct ipsecrequest **q; 947 struct ipsecrequest *r; 948 struct secpolicy *dst; 949 950 if (src == NULL) 951 return (NULL); 952 dst = KEY_NEWSP(); 953 if (dst == NULL) 954 return (NULL); 955 956 /* 957 * Deep-copy IPsec request chain. This is required since struct 958 * ipsecrequest is not reference counted. 959 */ 960 q = &newchain; 961 for (p = src->req; p; p = p->next) { 962 *q = ipsec_newisr(); 963 if (*q == NULL) 964 goto fail; 965 (*q)->saidx.proto = p->saidx.proto; 966 (*q)->saidx.mode = p->saidx.mode; 967 (*q)->level = p->level; 968 (*q)->saidx.reqid = p->saidx.reqid; 969 970 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src)); 971 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst)); 972 973 (*q)->sp = dst; 974 975 q = &((*q)->next); 976 } 977 978 dst->req = newchain; 979 dst->state = src->state; 980 dst->policy = src->policy; 981 /* Do not touch the refcnt fields. */ 982 983 return (dst); 984 985 fail: 986 for (p = newchain; p; p = r) { 987 r = p->next; 988 ipsec_delisr(p); 989 p = NULL; 990 } 991 return (NULL); 992 } 993 994 /* Set policy and IPsec request if present. */ 995 static int 996 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname, 997 caddr_t request, size_t len, struct ucred *cred) 998 { 999 INIT_VNET_IPSEC(curvnet); 1000 struct sadb_x_policy *xpl; 1001 struct secpolicy *newsp = NULL; 1002 int error; 1003 1004 /* Sanity check. */ 1005 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL) 1006 return (EINVAL); 1007 if (len < sizeof(*xpl)) 1008 return (EINVAL); 1009 xpl = (struct sadb_x_policy *)request; 1010 1011 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1012 printf("%s: passed policy\n", __func__); 1013 kdebug_sadb_x_policy((struct sadb_ext *)xpl)); 1014 1015 /* Check policy type. */ 1016 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */ 1017 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 1018 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1019 return (EINVAL); 1020 1021 /* Check privileged socket. */ 1022 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1023 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0); 1024 if (error) 1025 return (EACCES); 1026 } 1027 1028 /* Allocating new SP entry. */ 1029 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1030 return (error); 1031 1032 newsp->state = IPSEC_SPSTATE_ALIVE; 1033 1034 /* Clear old SP and set new SP. */ 1035 KEY_FREESP(pcb_sp); 1036 *pcb_sp = newsp; 1037 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1038 printf("%s: new policy\n", __func__); 1039 kdebug_secpolicy(newsp)); 1040 1041 return (0); 1042 } 1043 1044 int 1045 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request, 1046 size_t len, struct ucred *cred) 1047 { 1048 INIT_VNET_IPSEC(curvnet); 1049 struct sadb_x_policy *xpl; 1050 struct secpolicy **pcb_sp; 1051 1052 /* Sanity check. */ 1053 if (inp == NULL || request == NULL) 1054 return (EINVAL); 1055 if (len < sizeof(*xpl)) 1056 return (EINVAL); 1057 xpl = (struct sadb_x_policy *)request; 1058 1059 /* Select direction. */ 1060 switch (xpl->sadb_x_policy_dir) { 1061 case IPSEC_DIR_INBOUND: 1062 pcb_sp = &inp->inp_sp->sp_in; 1063 break; 1064 case IPSEC_DIR_OUTBOUND: 1065 pcb_sp = &inp->inp_sp->sp_out; 1066 break; 1067 default: 1068 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1069 xpl->sadb_x_policy_dir)); 1070 return (EINVAL); 1071 } 1072 1073 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred)); 1074 } 1075 1076 int 1077 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len, 1078 struct mbuf **mp) 1079 { 1080 INIT_VNET_IPSEC(curvnet); 1081 struct sadb_x_policy *xpl; 1082 struct secpolicy *pcb_sp; 1083 1084 /* Sanity check. */ 1085 if (inp == NULL || request == NULL || mp == NULL) 1086 return (EINVAL); 1087 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 1088 if (len < sizeof(*xpl)) 1089 return (EINVAL); 1090 xpl = (struct sadb_x_policy *)request; 1091 1092 /* Select direction. */ 1093 switch (xpl->sadb_x_policy_dir) { 1094 case IPSEC_DIR_INBOUND: 1095 pcb_sp = inp->inp_sp->sp_in; 1096 break; 1097 case IPSEC_DIR_OUTBOUND: 1098 pcb_sp = inp->inp_sp->sp_out; 1099 break; 1100 default: 1101 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1102 xpl->sadb_x_policy_dir)); 1103 return (EINVAL); 1104 } 1105 1106 /* Sanity check. Should be an IPSEC_ASSERT. */ 1107 if (pcb_sp == NULL) 1108 return (EINVAL); 1109 1110 *mp = key_sp2msg(pcb_sp); 1111 if (!*mp) { 1112 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 1113 return (ENOBUFS); 1114 } 1115 1116 (*mp)->m_type = MT_DATA; 1117 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1118 printf("%s:\n", __func__); kdebug_mbuf(*mp)); 1119 1120 return (0); 1121 } 1122 1123 /* Delete policy in PCB. */ 1124 int 1125 ipsec_delete_pcbpolicy(struct inpcb *inp) 1126 { 1127 IPSEC_ASSERT(inp != NULL, ("null inp")); 1128 1129 if (inp->inp_sp == NULL) 1130 return (0); 1131 1132 if (inp->inp_sp->sp_in != NULL) 1133 KEY_FREESP(&inp->inp_sp->sp_in); 1134 1135 if (inp->inp_sp->sp_out != NULL) 1136 KEY_FREESP(&inp->inp_sp->sp_out); 1137 1138 ipsec_delpcbpolicy(inp->inp_sp); 1139 inp->inp_sp = NULL; 1140 1141 return (0); 1142 } 1143 1144 /* 1145 * Return current level. 1146 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1147 */ 1148 u_int 1149 ipsec_get_reqlevel(struct ipsecrequest *isr) 1150 { 1151 INIT_VNET_IPSEC(curvnet); 1152 u_int level = 0; 1153 u_int esp_trans_deflev, esp_net_deflev; 1154 u_int ah_trans_deflev, ah_net_deflev; 1155 1156 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument")); 1157 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1158 ("af family mismatch, src %u, dst %u", 1159 isr->sp->spidx.src.sa.sa_family, 1160 isr->sp->spidx.dst.sa.sa_family)); 1161 1162 /* XXX Note that we have ipseclog() expanded here - code sync issue. */ 1163 #define IPSEC_CHECK_DEFAULT(lev) \ 1164 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1165 && (lev) != IPSEC_LEVEL_UNIQUE) \ 1166 ? (V_ipsec_debug \ 1167 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\ 1168 (lev), IPSEC_LEVEL_REQUIRE) \ 1169 : 0), \ 1170 (lev) = IPSEC_LEVEL_REQUIRE, \ 1171 (lev) \ 1172 : (lev)) 1173 1174 /* Set default level. */ 1175 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1176 #ifdef INET 1177 case AF_INET: 1178 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev); 1179 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev); 1180 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev); 1181 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev); 1182 break; 1183 #endif 1184 #ifdef INET6 1185 case AF_INET6: 1186 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev); 1187 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev); 1188 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev); 1189 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev); 1190 break; 1191 #endif /* INET6 */ 1192 default: 1193 panic("%s: unknown af %u", 1194 __func__, isr->sp->spidx.src.sa.sa_family); 1195 } 1196 1197 #undef IPSEC_CHECK_DEFAULT 1198 1199 /* Set level. */ 1200 switch (isr->level) { 1201 case IPSEC_LEVEL_DEFAULT: 1202 switch (isr->saidx.proto) { 1203 case IPPROTO_ESP: 1204 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1205 level = esp_net_deflev; 1206 else 1207 level = esp_trans_deflev; 1208 break; 1209 case IPPROTO_AH: 1210 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1211 level = ah_net_deflev; 1212 else 1213 level = ah_trans_deflev; 1214 break; 1215 case IPPROTO_IPCOMP: 1216 /* 1217 * We don't really care, as IPcomp document says that 1218 * we shouldn't compress small packets. 1219 */ 1220 level = IPSEC_LEVEL_USE; 1221 break; 1222 default: 1223 panic("%s: Illegal protocol defined %u\n", __func__, 1224 isr->saidx.proto); 1225 } 1226 break; 1227 1228 case IPSEC_LEVEL_USE: 1229 case IPSEC_LEVEL_REQUIRE: 1230 level = isr->level; 1231 break; 1232 case IPSEC_LEVEL_UNIQUE: 1233 level = IPSEC_LEVEL_REQUIRE; 1234 break; 1235 1236 default: 1237 panic("%s: Illegal IPsec level %u\n", __func__, isr->level); 1238 } 1239 1240 return (level); 1241 } 1242 1243 /* 1244 * Check security policy requirements against the actual 1245 * packet contents. Return one if the packet should be 1246 * reject as "invalid"; otherwiser return zero to have the 1247 * packet treated as "valid". 1248 * 1249 * OUT: 1250 * 0: valid 1251 * 1: invalid 1252 */ 1253 int 1254 ipsec_in_reject(struct secpolicy *sp, struct mbuf *m) 1255 { 1256 INIT_VNET_IPSEC(curvnet); 1257 struct ipsecrequest *isr; 1258 int need_auth; 1259 1260 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1261 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1262 1263 /* Check policy. */ 1264 switch (sp->policy) { 1265 case IPSEC_POLICY_DISCARD: 1266 return (1); 1267 case IPSEC_POLICY_BYPASS: 1268 case IPSEC_POLICY_NONE: 1269 return (0); 1270 } 1271 1272 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1273 ("invalid policy %u", sp->policy)); 1274 1275 /* XXX Should compare policy against IPsec header history. */ 1276 1277 need_auth = 0; 1278 for (isr = sp->req; isr != NULL; isr = isr->next) { 1279 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1280 continue; 1281 switch (isr->saidx.proto) { 1282 case IPPROTO_ESP: 1283 if ((m->m_flags & M_DECRYPTED) == 0) { 1284 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1285 printf("%s: ESP m_flags:%x\n", __func__, 1286 m->m_flags)); 1287 return (1); 1288 } 1289 1290 if (!need_auth && 1291 isr->sav != NULL && 1292 isr->sav->tdb_authalgxform != NULL && 1293 (m->m_flags & M_AUTHIPDGM) == 0) { 1294 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1295 printf("%s: ESP/AH m_flags:%x\n", __func__, 1296 m->m_flags)); 1297 return (1); 1298 } 1299 break; 1300 case IPPROTO_AH: 1301 need_auth = 1; 1302 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1303 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1304 printf("%s: AH m_flags:%x\n", __func__, 1305 m->m_flags)); 1306 return (1); 1307 } 1308 break; 1309 case IPPROTO_IPCOMP: 1310 /* 1311 * We don't really care, as IPcomp document 1312 * says that we shouldn't compress small 1313 * packets. IPComp policy should always be 1314 * treated as being in "use" level. 1315 */ 1316 break; 1317 } 1318 } 1319 return (0); /* Valid. */ 1320 } 1321 1322 static int 1323 ipsec46_in_reject(struct mbuf *m, struct inpcb *inp) 1324 { 1325 struct secpolicy *sp; 1326 int error; 1327 int result; 1328 1329 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1330 1331 /* 1332 * Get SP for this packet. 1333 * When we are called from ip_forward(), we call 1334 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1335 */ 1336 if (inp == NULL) 1337 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1338 else 1339 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error); 1340 1341 if (sp != NULL) { 1342 result = ipsec_in_reject(sp, m); 1343 KEY_FREESP(&sp); 1344 } else { 1345 result = 0; /* XXX Should be panic? 1346 * -> No, there may be error. */ 1347 } 1348 return (result); 1349 } 1350 1351 /* 1352 * Check AH/ESP integrity. 1353 * This function is called from tcp_input(), udp_input(), 1354 * and {ah,esp}4_input for tunnel mode. 1355 */ 1356 int 1357 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1358 { 1359 INIT_VNET_IPSEC(curvnet); 1360 int result; 1361 1362 result = ipsec46_in_reject(m, inp); 1363 if (result) 1364 V_ipsec4stat.ips_in_polvio++; 1365 1366 return (result); 1367 } 1368 1369 #ifdef INET6 1370 /* 1371 * Check AH/ESP integrity. 1372 * This function is called from tcp6_input(), udp6_input(), 1373 * and {ah,esp}6_input for tunnel mode. 1374 */ 1375 int 1376 ipsec6_in_reject(struct mbuf *m, struct inpcb *inp) 1377 { 1378 INIT_VNET_IPSEC(curvnet); 1379 int result; 1380 1381 result = ipsec46_in_reject(m, inp); 1382 if (result) 1383 V_ipsec6stat.ips_in_polvio++; 1384 1385 return (result); 1386 } 1387 #endif 1388 1389 /* 1390 * Compute the byte size to be occupied by IPsec header. 1391 * In case it is tunnelled, it includes the size of outer IP header. 1392 * NOTE: SP passed is freed in this function. 1393 */ 1394 static size_t 1395 ipsec_hdrsiz_internal(struct secpolicy *sp) 1396 { 1397 INIT_VNET_IPSEC(curvnet); 1398 struct ipsecrequest *isr; 1399 size_t size; 1400 1401 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1402 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1403 1404 switch (sp->policy) { 1405 case IPSEC_POLICY_DISCARD: 1406 case IPSEC_POLICY_BYPASS: 1407 case IPSEC_POLICY_NONE: 1408 return (0); 1409 } 1410 1411 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1412 ("invalid policy %u", sp->policy)); 1413 1414 size = 0; 1415 for (isr = sp->req; isr != NULL; isr = isr->next) { 1416 size_t clen = 0; 1417 1418 switch (isr->saidx.proto) { 1419 case IPPROTO_ESP: 1420 clen = esp_hdrsiz(isr->sav); 1421 break; 1422 case IPPROTO_AH: 1423 clen = ah_hdrsiz(isr->sav); 1424 break; 1425 case IPPROTO_IPCOMP: 1426 clen = sizeof(struct ipcomp); 1427 break; 1428 } 1429 1430 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1431 switch (isr->saidx.dst.sa.sa_family) { 1432 case AF_INET: 1433 clen += sizeof(struct ip); 1434 break; 1435 #ifdef INET6 1436 case AF_INET6: 1437 clen += sizeof(struct ip6_hdr); 1438 break; 1439 #endif 1440 default: 1441 ipseclog((LOG_ERR, "%s: unknown AF %d in " 1442 "IPsec tunnel SA\n", __func__, 1443 ((struct sockaddr *)&isr->saidx.dst)->sa_family)); 1444 break; 1445 } 1446 } 1447 size += clen; 1448 } 1449 1450 return (size); 1451 } 1452 1453 /* 1454 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(), 1455 * disabled ip6_ipsec_mtu() and ip6_forward(). 1456 */ 1457 size_t 1458 ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1459 { 1460 INIT_VNET_IPSEC(curvnet); 1461 struct secpolicy *sp; 1462 int error; 1463 size_t size; 1464 1465 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1466 1467 /* Get SP for this packet. 1468 * When we are called from ip_forward(), we call 1469 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1470 */ 1471 if (inp == NULL) 1472 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1473 else 1474 sp = ipsec_getpolicybysock(m, dir, inp, &error); 1475 1476 if (sp != NULL) { 1477 size = ipsec_hdrsiz_internal(sp); 1478 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1479 printf("%s: size:%lu.\n", __func__, 1480 (unsigned long)size)); 1481 1482 KEY_FREESP(&sp); 1483 } else { 1484 size = 0; /* XXX Should be panic? 1485 * -> No, we are called w/o knowing if 1486 * IPsec processing is needed. */ 1487 } 1488 return (size); 1489 } 1490 1491 /* 1492 * Check the variable replay window. 1493 * ipsec_chkreplay() performs replay check before ICV verification. 1494 * ipsec_updatereplay() updates replay bitmap. This must be called after 1495 * ICV verification (it also performs replay check, which is usually done 1496 * beforehand). 1497 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1498 * 1499 * Based on RFC 2401. 1500 */ 1501 int 1502 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav) 1503 { 1504 const struct secreplay *replay; 1505 u_int32_t diff; 1506 int fr; 1507 u_int32_t wsizeb; /* Constant: bits of window size. */ 1508 int frlast; /* Constant: last frame. */ 1509 1510 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1511 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1512 1513 replay = sav->replay; 1514 1515 if (replay->wsize == 0) 1516 return (1); /* No need to check replay. */ 1517 1518 /* Constant. */ 1519 frlast = replay->wsize - 1; 1520 wsizeb = replay->wsize << 3; 1521 1522 /* Sequence number of 0 is invalid. */ 1523 if (seq == 0) 1524 return (0); 1525 1526 /* First time is always okay. */ 1527 if (replay->count == 0) 1528 return (1); 1529 1530 if (seq > replay->lastseq) { 1531 /* Larger sequences are okay. */ 1532 return (1); 1533 } else { 1534 /* seq is equal or less than lastseq. */ 1535 diff = replay->lastseq - seq; 1536 1537 /* Over range to check, i.e. too old or wrapped. */ 1538 if (diff >= wsizeb) 1539 return (0); 1540 1541 fr = frlast - diff / 8; 1542 1543 /* This packet already seen? */ 1544 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1545 return (0); 1546 1547 /* Out of order but good. */ 1548 return (1); 1549 } 1550 } 1551 1552 /* 1553 * Check replay counter whether to update or not. 1554 * OUT: 0: OK 1555 * 1: NG 1556 */ 1557 int 1558 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav) 1559 { 1560 INIT_VNET_IPSEC(curvnet); 1561 struct secreplay *replay; 1562 u_int32_t diff; 1563 int fr; 1564 u_int32_t wsizeb; /* Constant: bits of window size. */ 1565 int frlast; /* Constant: last frame. */ 1566 1567 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1568 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1569 1570 replay = sav->replay; 1571 1572 if (replay->wsize == 0) 1573 goto ok; /* No need to check replay. */ 1574 1575 /* Constant. */ 1576 frlast = replay->wsize - 1; 1577 wsizeb = replay->wsize << 3; 1578 1579 /* Sequence number of 0 is invalid. */ 1580 if (seq == 0) 1581 return (1); 1582 1583 /* First time. */ 1584 if (replay->count == 0) { 1585 replay->lastseq = seq; 1586 bzero(replay->bitmap, replay->wsize); 1587 (replay->bitmap)[frlast] = 1; 1588 goto ok; 1589 } 1590 1591 if (seq > replay->lastseq) { 1592 /* seq is larger than lastseq. */ 1593 diff = seq - replay->lastseq; 1594 1595 /* New larger sequence number. */ 1596 if (diff < wsizeb) { 1597 /* In window. */ 1598 /* Set bit for this packet. */ 1599 vshiftl(replay->bitmap, diff, replay->wsize); 1600 (replay->bitmap)[frlast] |= 1; 1601 } else { 1602 /* This packet has a "way larger". */ 1603 bzero(replay->bitmap, replay->wsize); 1604 (replay->bitmap)[frlast] = 1; 1605 } 1606 replay->lastseq = seq; 1607 1608 /* Larger is good. */ 1609 } else { 1610 /* seq is equal or less than lastseq. */ 1611 diff = replay->lastseq - seq; 1612 1613 /* Over range to check, i.e. too old or wrapped. */ 1614 if (diff >= wsizeb) 1615 return (1); 1616 1617 fr = frlast - diff / 8; 1618 1619 /* This packet already seen? */ 1620 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1621 return (1); 1622 1623 /* Mark as seen. */ 1624 (replay->bitmap)[fr] |= (1 << (diff % 8)); 1625 1626 /* Out of order but good. */ 1627 } 1628 1629 ok: 1630 if (replay->count == ~0) { 1631 1632 /* Set overflow flag. */ 1633 replay->overflow++; 1634 1635 /* Don't increment, no more packets accepted. */ 1636 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 1637 return (1); 1638 1639 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1640 __func__, replay->overflow, ipsec_logsastr(sav))); 1641 } 1642 1643 replay->count++; 1644 1645 return (0); 1646 } 1647 1648 /* 1649 * Shift variable length buffer to left. 1650 * IN: bitmap: pointer to the buffer 1651 * nbit: the number of to shift. 1652 * wsize: buffer size (bytes). 1653 */ 1654 static void 1655 vshiftl(unsigned char *bitmap, int nbit, int wsize) 1656 { 1657 int s, j, i; 1658 unsigned char over; 1659 1660 for (j = 0; j < nbit; j += 8) { 1661 s = (nbit - j < 8) ? (nbit - j): 8; 1662 bitmap[0] <<= s; 1663 for (i = 1; i < wsize; i++) { 1664 over = (bitmap[i] >> (8 - s)); 1665 bitmap[i] <<= s; 1666 bitmap[i-1] |= over; 1667 } 1668 } 1669 } 1670 1671 /* Return a printable string for the IPv4 address. */ 1672 static char * 1673 inet_ntoa4(struct in_addr ina) 1674 { 1675 static char buf[4][4 * sizeof "123" + 4]; 1676 unsigned char *ucp = (unsigned char *) &ina; 1677 static int i = 3; 1678 1679 /* XXX-BZ Returns static buffer. */ 1680 i = (i + 1) % 4; 1681 sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff, 1682 ucp[2] & 0xff, ucp[3] & 0xff); 1683 return (buf[i]); 1684 } 1685 1686 /* Return a printable string for the address. */ 1687 char * 1688 ipsec_address(union sockaddr_union* sa) 1689 { 1690 #ifdef INET6 1691 char ip6buf[INET6_ADDRSTRLEN]; 1692 #endif 1693 1694 switch (sa->sa.sa_family) { 1695 #ifdef INET 1696 case AF_INET: 1697 return (inet_ntoa4(sa->sin.sin_addr)); 1698 #endif /* INET */ 1699 #ifdef INET6 1700 case AF_INET6: 1701 return (ip6_sprintf(ip6buf, &sa->sin6.sin6_addr)); 1702 #endif /* INET6 */ 1703 default: 1704 return ("(unknown address family)"); 1705 } 1706 } 1707 1708 const char * 1709 ipsec_logsastr(struct secasvar *sav) 1710 { 1711 static char buf[256]; 1712 char *p; 1713 struct secasindex *saidx = &sav->sah->saidx; 1714 1715 IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 1716 ("address family mismatch")); 1717 1718 p = buf; 1719 snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi)); 1720 while (p && *p) 1721 p++; 1722 /* NB: only use ipsec_address on one address at a time. */ 1723 snprintf(p, sizeof (buf) - (p - buf), "src=%s ", 1724 ipsec_address(&saidx->src)); 1725 while (p && *p) 1726 p++; 1727 snprintf(p, sizeof (buf) - (p - buf), "dst=%s)", 1728 ipsec_address(&saidx->dst)); 1729 1730 return (buf); 1731 } 1732 1733 void 1734 ipsec_dumpmbuf(struct mbuf *m) 1735 { 1736 int totlen; 1737 int i; 1738 u_char *p; 1739 1740 totlen = 0; 1741 printf("---\n"); 1742 while (m) { 1743 p = mtod(m, u_char *); 1744 for (i = 0; i < m->m_len; i++) { 1745 printf("%02x ", p[i]); 1746 totlen++; 1747 if (totlen % 16 == 0) 1748 printf("\n"); 1749 } 1750 m = m->m_next; 1751 } 1752 if (totlen % 16 != 0) 1753 printf("\n"); 1754 printf("---\n"); 1755 } 1756 1757 static void 1758 ipsec_attach(void) 1759 { 1760 1761 SECPOLICY_LOCK_INIT(&V_ip4_def_policy); 1762 V_ip4_def_policy.refcnt = 1; /* NB: disallow free. */ 1763 } 1764 SYSINIT(ipsec, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST, ipsec_attach, NULL); 1765 1766 1767 /* XXX This stuff doesn't belong here... */ 1768 1769 static struct xformsw* xforms = NULL; 1770 1771 /* 1772 * Register a transform; typically at system startup. 1773 */ 1774 void 1775 xform_register(struct xformsw* xsp) 1776 { 1777 1778 xsp->xf_next = xforms; 1779 xforms = xsp; 1780 } 1781 1782 /* 1783 * Initialize transform support in an sav. 1784 */ 1785 int 1786 xform_init(struct secasvar *sav, int xftype) 1787 { 1788 struct xformsw *xsp; 1789 1790 if (sav->tdb_xform != NULL) /* Previously initialized. */ 1791 return (0); 1792 for (xsp = xforms; xsp; xsp = xsp->xf_next) 1793 if (xsp->xf_type == xftype) 1794 return ((*xsp->xf_init)(sav, xsp)); 1795 return (EINVAL); 1796 } 1797