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/hhook.h> 52 #include <sys/time.h> 53 #include <sys/kernel.h> 54 #include <sys/syslog.h> 55 #include <sys/sysctl.h> 56 #include <sys/proc.h> 57 58 #include <net/if.h> 59 #include <net/if_enc.h> 60 #include <net/if_var.h> 61 #include <net/vnet.h> 62 63 #include <netinet/in.h> 64 #include <netinet/in_systm.h> 65 #include <netinet/ip.h> 66 #include <netinet/ip_var.h> 67 #include <netinet/in_var.h> 68 #include <netinet/udp.h> 69 #include <netinet/udp_var.h> 70 #include <netinet/tcp.h> 71 #include <netinet/udp.h> 72 73 #include <netinet/ip6.h> 74 #ifdef INET6 75 #include <netinet6/ip6_var.h> 76 #endif 77 #include <netinet/in_pcb.h> 78 #ifdef INET6 79 #include <netinet/icmp6.h> 80 #endif 81 82 #include <sys/types.h> 83 #include <netipsec/ipsec.h> 84 #ifdef INET6 85 #include <netipsec/ipsec6.h> 86 #endif 87 #include <netipsec/ah_var.h> 88 #include <netipsec/esp_var.h> 89 #include <netipsec/ipcomp.h> /*XXX*/ 90 #include <netipsec/ipcomp_var.h> 91 92 #include <netipsec/key.h> 93 #include <netipsec/keydb.h> 94 #include <netipsec/key_debug.h> 95 96 #include <netipsec/xform.h> 97 98 #include <machine/in_cksum.h> 99 100 #include <opencrypto/cryptodev.h> 101 102 #ifdef IPSEC_DEBUG 103 VNET_DEFINE(int, ipsec_debug) = 1; 104 #else 105 VNET_DEFINE(int, ipsec_debug) = 0; 106 #endif 107 108 /* NB: name changed so netstat doesn't use it. */ 109 VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec4stat); 110 VNET_PCPUSTAT_SYSINIT(ipsec4stat); 111 112 #ifdef VIMAGE 113 VNET_PCPUSTAT_SYSUNINIT(ipsec4stat); 114 #endif /* VIMAGE */ 115 116 VNET_DEFINE(int, ip4_ah_offsetmask) = 0; /* maybe IP_DF? */ 117 /* DF bit on encap. 0: clear 1: set 2: copy */ 118 VNET_DEFINE(int, ip4_ipsec_dfbit) = 0; 119 VNET_DEFINE(int, ip4_esp_trans_deflev) = IPSEC_LEVEL_USE; 120 VNET_DEFINE(int, ip4_esp_net_deflev) = IPSEC_LEVEL_USE; 121 VNET_DEFINE(int, ip4_ah_trans_deflev) = IPSEC_LEVEL_USE; 122 VNET_DEFINE(int, ip4_ah_net_deflev) = IPSEC_LEVEL_USE; 123 /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 124 VNET_DEFINE(int, ip4_ipsec_ecn) = 0; 125 VNET_DEFINE(int, ip4_esp_randpad) = -1; 126 127 static VNET_DEFINE(struct secpolicy, def_policy); 128 #define V_def_policy VNET(def_policy) 129 /* 130 * Crypto support requirements: 131 * 132 * 1 require hardware support 133 * -1 require software support 134 * 0 take anything 135 */ 136 VNET_DEFINE(int, crypto_support) = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE; 137 138 FEATURE(ipsec, "Internet Protocol Security (IPsec)"); 139 #ifdef IPSEC_NAT_T 140 FEATURE(ipsec_natt, "UDP Encapsulation of IPsec ESP Packets ('NAT-T')"); 141 #endif 142 143 SYSCTL_DECL(_net_inet_ipsec); 144 145 /* net.inet.ipsec */ 146 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy, 147 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(def_policy).policy, 0, 148 "IPsec default policy."); 149 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev, 150 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_esp_trans_deflev), 0, 151 "Default ESP transport mode level"); 152 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev, 153 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_esp_net_deflev), 0, 154 "Default ESP tunnel mode level."); 155 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev, 156 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ah_trans_deflev), 0, 157 "AH transfer mode default level."); 158 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev, 159 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ah_net_deflev), 0, 160 "AH tunnel mode default level."); 161 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos, 162 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ah_cleartos), 0, 163 "If set clear type-of-service field when doing AH computation."); 164 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, ah_offsetmask, 165 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ah_offsetmask), 0, 166 "If not set clear offset field mask when doing AH computation."); 167 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit, 168 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ipsec_dfbit), 0, 169 "Do not fragment bit on encap."); 170 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn, 171 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ipsec_ecn), 0, 172 "Explicit Congestion Notification handling."); 173 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEBUG, debug, 174 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0, 175 "Enable IPsec debugging output when set."); 176 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, crypto_support, 177 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(crypto_support), 0, 178 "Crypto driver selection."); 179 SYSCTL_VNET_PCPUSTAT(_net_inet_ipsec, OID_AUTO, ipsecstats, struct ipsecstat, 180 ipsec4stat, "IPsec IPv4 statistics."); 181 182 #ifdef REGRESSION 183 /* 184 * When set to 1, IPsec will send packets with the same sequence number. 185 * This allows to verify if the other side has proper replay attacks detection. 186 */ 187 VNET_DEFINE(int, ipsec_replay) = 0; 188 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_replay, 189 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipsec_replay), 0, 190 "Emulate replay attack"); 191 /* 192 * When set 1, IPsec will send packets with corrupted HMAC. 193 * This allows to verify if the other side properly detects modified packets. 194 */ 195 VNET_DEFINE(int, ipsec_integrity) = 0; 196 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_integrity, 197 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipsec_integrity), 0, 198 "Emulate man-in-the-middle attack"); 199 #endif 200 201 #ifdef INET6 202 VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec6stat); 203 VNET_PCPUSTAT_SYSINIT(ipsec6stat); 204 205 #ifdef VIMAGE 206 VNET_PCPUSTAT_SYSUNINIT(ipsec6stat); 207 #endif /* VIMAGE */ 208 209 VNET_DEFINE(int, ip6_esp_trans_deflev) = IPSEC_LEVEL_USE; 210 VNET_DEFINE(int, ip6_esp_net_deflev) = IPSEC_LEVEL_USE; 211 VNET_DEFINE(int, ip6_ah_trans_deflev) = IPSEC_LEVEL_USE; 212 VNET_DEFINE(int, ip6_ah_net_deflev) = IPSEC_LEVEL_USE; 213 VNET_DEFINE(int, ip6_ipsec_ecn) = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 214 215 SYSCTL_DECL(_net_inet6_ipsec6); 216 217 /* net.inet6.ipsec6 */ 218 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy, 219 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(def_policy).policy, 0, 220 "IPsec default policy."); 221 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev, 222 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_esp_trans_deflev), 0, 223 "Default ESP transport mode level."); 224 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev, 225 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_esp_net_deflev), 0, 226 "Default ESP tunnel mode level."); 227 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev, 228 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ah_trans_deflev), 0, 229 "AH transfer mode default level."); 230 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev, 231 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ah_net_deflev), 0, 232 "AH tunnel mode default level."); 233 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_ECN, ecn, 234 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ipsec_ecn), 0, 235 "Explicit Congestion Notification handling."); 236 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEBUG, debug, 237 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0, 238 "Enable IPsec debugging output when set."); 239 SYSCTL_VNET_PCPUSTAT(_net_inet6_ipsec6, IPSECCTL_STATS, ipsecstats, 240 struct ipsecstat, ipsec6stat, "IPsec IPv6 statistics."); 241 #endif /* INET6 */ 242 243 static int ipsec_in_reject(struct secpolicy *, const struct mbuf *); 244 static int ipsec_setspidx_inpcb(const struct mbuf *, struct inpcb *, u_int); 245 static int ipsec_setspidx(const struct mbuf *, struct secpolicyindex *, int); 246 static void ipsec4_get_ulp(const struct mbuf *m, struct secpolicyindex *, int); 247 static int ipsec4_setspidx_ipaddr(const struct mbuf *, struct secpolicyindex *); 248 #ifdef INET6 249 static void ipsec6_get_ulp(const struct mbuf *m, struct secpolicyindex *, int); 250 static int ipsec6_setspidx_ipaddr(const struct mbuf *, struct secpolicyindex *); 251 #endif 252 static void ipsec_delpcbpolicy(struct inpcbpolicy *); 253 static struct secpolicy *ipsec_deepcopy_policy(struct secpolicy *src); 254 255 MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy"); 256 257 /* 258 * Return a held reference to the default SP. 259 */ 260 static struct secpolicy * 261 key_allocsp_default(const char* where, int tag) 262 { 263 struct secpolicy *sp; 264 265 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 266 printf("DP key_allocsp_default from %s:%u\n", where, tag)); 267 268 sp = &V_def_policy; 269 if (sp->policy != IPSEC_POLICY_DISCARD && 270 sp->policy != IPSEC_POLICY_NONE) { 271 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n", 272 sp->policy, IPSEC_POLICY_NONE)); 273 sp->policy = IPSEC_POLICY_NONE; 274 } 275 key_addref(sp); 276 277 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 278 printf("DP key_allocsp_default returns SP:%p (%u)\n", 279 sp, sp->refcnt)); 280 return (sp); 281 } 282 #define KEY_ALLOCSP_DEFAULT() \ 283 key_allocsp_default(__FILE__, __LINE__) 284 285 /* 286 * For OUTBOUND packet having a socket. Searching SPD for packet, 287 * and return a pointer to SP. 288 * OUT: NULL: no apropreate SP found, the following value is set to error. 289 * 0 : bypass 290 * EACCES : discard packet. 291 * ENOENT : ipsec_acquire() in progress, maybe. 292 * others : error occurred. 293 * others: a pointer to SP 294 * 295 * NOTE: IPv6 mapped adddress concern is implemented here. 296 */ 297 struct secpolicy * 298 ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir) 299 { 300 struct secpolicy *sp; 301 302 IPSEC_ASSERT(tdbi != NULL, ("null tdbi")); 303 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 304 ("invalid direction %u", dir)); 305 306 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir); 307 if (sp == NULL) /*XXX????*/ 308 sp = KEY_ALLOCSP_DEFAULT(); 309 IPSEC_ASSERT(sp != NULL, ("null SP")); 310 return (sp); 311 } 312 313 /* 314 * For OUTBOUND packet having a socket. Searching SPD for packet, 315 * and return a pointer to SP. 316 * OUT: NULL: no apropreate SP found, the following value is set to error. 317 * 0 : bypass 318 * EACCES : discard packet. 319 * ENOENT : ipsec_acquire() in progress, maybe. 320 * others : error occurred. 321 * others: a pointer to SP 322 * 323 * NOTE: IPv6 mapped adddress concern is implemented here. 324 */ 325 static struct secpolicy * 326 ipsec_getpolicybysock(const struct mbuf *m, u_int dir, struct inpcb *inp, 327 int *error) 328 { 329 struct inpcbpolicy *pcbsp; 330 struct secpolicy *currsp = NULL; /* Policy on socket. */ 331 struct secpolicy *sp; 332 333 IPSEC_ASSERT(m != NULL, ("null mbuf")); 334 IPSEC_ASSERT(inp != NULL, ("null inpcb")); 335 IPSEC_ASSERT(error != NULL, ("null error")); 336 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 337 ("invalid direction %u", dir)); 338 339 if (!key_havesp(dir)) { 340 /* No SP found, use system default. */ 341 sp = KEY_ALLOCSP_DEFAULT(); 342 return (sp); 343 } 344 345 /* Set spidx in pcb. */ 346 *error = ipsec_setspidx_inpcb(m, inp, dir); 347 if (*error) 348 return (NULL); 349 350 pcbsp = inp->inp_sp; 351 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp")); 352 switch (dir) { 353 case IPSEC_DIR_INBOUND: 354 currsp = pcbsp->sp_in; 355 break; 356 case IPSEC_DIR_OUTBOUND: 357 currsp = pcbsp->sp_out; 358 break; 359 } 360 IPSEC_ASSERT(currsp != NULL, ("null currsp")); 361 362 if (pcbsp->priv) { /* When privilieged socket. */ 363 switch (currsp->policy) { 364 case IPSEC_POLICY_BYPASS: 365 case IPSEC_POLICY_IPSEC: 366 key_addref(currsp); 367 sp = currsp; 368 break; 369 370 case IPSEC_POLICY_ENTRUST: 371 /* Look for a policy in SPD. */ 372 sp = KEY_ALLOCSP(&currsp->spidx, dir); 373 if (sp == NULL) /* No SP found. */ 374 sp = KEY_ALLOCSP_DEFAULT(); 375 break; 376 377 default: 378 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n", 379 __func__, currsp->policy)); 380 *error = EINVAL; 381 return (NULL); 382 } 383 } else { /* Unpriv, SPD has policy. */ 384 sp = KEY_ALLOCSP(&currsp->spidx, dir); 385 if (sp == NULL) { /* No SP found. */ 386 switch (currsp->policy) { 387 case IPSEC_POLICY_BYPASS: 388 ipseclog((LOG_ERR, "%s: Illegal policy for " 389 "non-priviliged defined %d\n", 390 __func__, currsp->policy)); 391 *error = EINVAL; 392 return (NULL); 393 394 case IPSEC_POLICY_ENTRUST: 395 sp = KEY_ALLOCSP_DEFAULT(); 396 break; 397 398 case IPSEC_POLICY_IPSEC: 399 key_addref(currsp); 400 sp = currsp; 401 break; 402 403 default: 404 ipseclog((LOG_ERR, "%s: Invalid policy for " 405 "PCB %d\n", __func__, currsp->policy)); 406 *error = EINVAL; 407 return (NULL); 408 } 409 } 410 } 411 IPSEC_ASSERT(sp != NULL, 412 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy)); 413 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 414 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n", 415 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt)); 416 return (sp); 417 } 418 419 /* 420 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 421 * and return a pointer to SP. 422 * OUT: positive: a pointer to the entry for security policy leaf matched. 423 * NULL: no apropreate SP found, the following value is set to error. 424 * 0 : bypass 425 * EACCES : discard packet. 426 * ENOENT : ipsec_acquire() in progress, maybe. 427 * others : error occurred. 428 */ 429 struct secpolicy * 430 ipsec_getpolicybyaddr(const struct mbuf *m, u_int dir, int *error) 431 { 432 struct secpolicyindex spidx; 433 struct secpolicy *sp; 434 435 IPSEC_ASSERT(m != NULL, ("null mbuf")); 436 IPSEC_ASSERT(error != NULL, ("null error")); 437 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 438 ("invalid direction %u", dir)); 439 440 sp = NULL; 441 *error = 0; 442 if (key_havesp(dir)) { 443 /* Make an index to look for a policy. */ 444 *error = ipsec_setspidx(m, &spidx, 0); 445 if (*error != 0) { 446 DPRINTF(("%s: setpidx failed, dir %u\n", 447 __func__, dir)); 448 return (NULL); 449 } 450 spidx.dir = dir; 451 sp = KEY_ALLOCSP(&spidx, dir); 452 } 453 if (sp == NULL) /* No SP found, use system default. */ 454 sp = KEY_ALLOCSP_DEFAULT(); 455 IPSEC_ASSERT(sp != NULL, ("null SP")); 456 return (sp); 457 } 458 459 struct secpolicy * 460 ipsec4_checkpolicy(const struct mbuf *m, u_int dir, int *error, 461 struct inpcb *inp) 462 { 463 struct secpolicy *sp; 464 465 *error = 0; 466 if (inp == NULL) 467 sp = ipsec_getpolicybyaddr(m, dir, error); 468 else 469 sp = ipsec_getpolicybysock(m, dir, inp, error); 470 if (sp == NULL) { 471 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error")); 472 IPSECSTAT_INC(ips_out_inval); 473 return (NULL); 474 } 475 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error)); 476 switch (sp->policy) { 477 case IPSEC_POLICY_ENTRUST: 478 default: 479 printf("%s: invalid policy %u\n", __func__, sp->policy); 480 /* FALLTHROUGH */ 481 case IPSEC_POLICY_DISCARD: 482 IPSECSTAT_INC(ips_out_polvio); 483 *error = -EINVAL; /* Packet is discarded by caller. */ 484 break; 485 case IPSEC_POLICY_BYPASS: 486 case IPSEC_POLICY_NONE: 487 KEY_FREESP(&sp); 488 sp = NULL; /* NB: force NULL result. */ 489 break; 490 case IPSEC_POLICY_IPSEC: 491 if (sp->req == NULL) /* Acquire a SA. */ 492 *error = key_spdacquire(sp); 493 break; 494 } 495 if (*error != 0) { 496 KEY_FREESP(&sp); 497 sp = NULL; 498 } 499 return (sp); 500 } 501 502 static int 503 ipsec_setspidx_inpcb(const struct mbuf *m, struct inpcb *inp, u_int dir) 504 { 505 struct secpolicyindex *spidx; 506 int error; 507 508 IPSEC_ASSERT(inp != NULL, ("null inp")); 509 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 510 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL, 511 ("null sp_in || sp_out")); 512 513 if (dir == IPSEC_DIR_INBOUND) 514 spidx = &inp->inp_sp->sp_in->spidx; 515 else 516 spidx = &inp->inp_sp->sp_out->spidx; 517 error = ipsec_setspidx(m, spidx, 1); 518 if (error == 0) { 519 spidx->dir = dir; 520 } else { 521 bzero(&inp->inp_sp->sp_in->spidx, 522 sizeof (inp->inp_sp->sp_in->spidx)); 523 bzero(&inp->inp_sp->sp_out->spidx, 524 sizeof (inp->inp_sp->sp_in->spidx)); 525 } 526 return (error); 527 } 528 529 /* 530 * Configure security policy index (src/dst/proto/sport/dport) 531 * by looking at the content of mbuf. 532 * The caller is responsible for error recovery (like clearing up spidx). 533 */ 534 static int 535 ipsec_setspidx(const struct mbuf *m, struct secpolicyindex *spidx, 536 int needport) 537 { 538 struct ip ipbuf; 539 const struct ip *ip = NULL; 540 const struct mbuf *n; 541 u_int v; 542 int len; 543 int error; 544 545 IPSEC_ASSERT(m != NULL, ("null mbuf")); 546 547 /* 548 * Validate m->m_pkthdr.len. We see incorrect length if we 549 * mistakenly call this function with inconsistent mbuf chain 550 * (like 4.4BSD tcp/udp processing). XXX Should we panic here? 551 */ 552 len = 0; 553 for (n = m; n; n = n->m_next) 554 len += n->m_len; 555 if (m->m_pkthdr.len != len) { 556 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 557 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n", 558 __func__, len, m->m_pkthdr.len)); 559 return (EINVAL); 560 } 561 562 if (m->m_pkthdr.len < sizeof(struct ip)) { 563 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 564 printf("%s: pkthdr len(%d) too small (v4), ignored.\n", 565 __func__, m->m_pkthdr.len)); 566 return (EINVAL); 567 } 568 569 if (m->m_len >= sizeof(*ip)) 570 ip = mtod(m, const struct ip *); 571 else { 572 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf); 573 ip = &ipbuf; 574 } 575 v = ip->ip_v; 576 switch (v) { 577 case 4: 578 error = ipsec4_setspidx_ipaddr(m, spidx); 579 if (error) 580 return (error); 581 ipsec4_get_ulp(m, spidx, needport); 582 return (0); 583 #ifdef INET6 584 case 6: 585 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 586 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 587 printf("%s: pkthdr len(%d) too small (v6), " 588 "ignored\n", __func__, m->m_pkthdr.len)); 589 return (EINVAL); 590 } 591 error = ipsec6_setspidx_ipaddr(m, spidx); 592 if (error) 593 return (error); 594 ipsec6_get_ulp(m, spidx, needport); 595 return (0); 596 #endif 597 default: 598 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 599 printf("%s: " "unknown IP version %u, ignored.\n", 600 __func__, v)); 601 return (EINVAL); 602 } 603 } 604 605 static void 606 ipsec4_get_ulp(const struct mbuf *m, struct secpolicyindex *spidx, 607 int needport) 608 { 609 u_int8_t nxt; 610 int off; 611 612 /* Sanity check. */ 613 IPSEC_ASSERT(m != NULL, ("null mbuf")); 614 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short")); 615 616 if (m->m_len >= sizeof (struct ip)) { 617 const struct ip *ip = mtod(m, const struct ip *); 618 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 619 goto done; 620 off = ip->ip_hl << 2; 621 nxt = ip->ip_p; 622 } else { 623 struct ip ih; 624 625 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih); 626 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 627 goto done; 628 off = ih.ip_hl << 2; 629 nxt = ih.ip_p; 630 } 631 632 while (off < m->m_pkthdr.len) { 633 struct ip6_ext ip6e; 634 struct tcphdr th; 635 struct udphdr uh; 636 637 switch (nxt) { 638 case IPPROTO_TCP: 639 spidx->ul_proto = nxt; 640 if (!needport) 641 goto done_proto; 642 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 643 goto done; 644 m_copydata(m, off, sizeof (th), (caddr_t) &th); 645 spidx->src.sin.sin_port = th.th_sport; 646 spidx->dst.sin.sin_port = th.th_dport; 647 return; 648 case IPPROTO_UDP: 649 spidx->ul_proto = nxt; 650 if (!needport) 651 goto done_proto; 652 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 653 goto done; 654 m_copydata(m, off, sizeof (uh), (caddr_t) &uh); 655 spidx->src.sin.sin_port = uh.uh_sport; 656 spidx->dst.sin.sin_port = uh.uh_dport; 657 return; 658 case IPPROTO_AH: 659 if (off + sizeof(ip6e) > m->m_pkthdr.len) 660 goto done; 661 /* XXX Sigh, this works but is totally bogus. */ 662 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e); 663 off += (ip6e.ip6e_len + 2) << 2; 664 nxt = ip6e.ip6e_nxt; 665 break; 666 case IPPROTO_ICMP: 667 default: 668 /* XXX Intermediate headers??? */ 669 spidx->ul_proto = nxt; 670 goto done_proto; 671 } 672 } 673 done: 674 spidx->ul_proto = IPSEC_ULPROTO_ANY; 675 done_proto: 676 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 677 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 678 } 679 680 /* Assumes that m is sane. */ 681 static int 682 ipsec4_setspidx_ipaddr(const struct mbuf *m, struct secpolicyindex *spidx) 683 { 684 static const struct sockaddr_in template = { 685 sizeof (struct sockaddr_in), 686 AF_INET, 687 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 688 }; 689 690 spidx->src.sin = template; 691 spidx->dst.sin = template; 692 693 if (m->m_len < sizeof (struct ip)) { 694 m_copydata(m, offsetof(struct ip, ip_src), 695 sizeof (struct in_addr), 696 (caddr_t) &spidx->src.sin.sin_addr); 697 m_copydata(m, offsetof(struct ip, ip_dst), 698 sizeof (struct in_addr), 699 (caddr_t) &spidx->dst.sin.sin_addr); 700 } else { 701 const struct ip *ip = mtod(m, const struct ip *); 702 spidx->src.sin.sin_addr = ip->ip_src; 703 spidx->dst.sin.sin_addr = ip->ip_dst; 704 } 705 706 spidx->prefs = sizeof(struct in_addr) << 3; 707 spidx->prefd = sizeof(struct in_addr) << 3; 708 709 return (0); 710 } 711 712 #ifdef INET6 713 static void 714 ipsec6_get_ulp(const struct mbuf *m, struct secpolicyindex *spidx, 715 int needport) 716 { 717 int off, nxt; 718 struct tcphdr th; 719 struct udphdr uh; 720 struct icmp6_hdr ih; 721 722 /* Sanity check. */ 723 if (m == NULL) 724 panic("%s: NULL pointer was passed.\n", __func__); 725 726 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 727 printf("%s:\n", __func__); kdebug_mbuf(m)); 728 729 /* Set default. */ 730 spidx->ul_proto = IPSEC_ULPROTO_ANY; 731 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 732 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 733 734 nxt = -1; 735 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 736 if (off < 0 || m->m_pkthdr.len < off) 737 return; 738 739 switch (nxt) { 740 case IPPROTO_TCP: 741 spidx->ul_proto = nxt; 742 if (!needport) 743 break; 744 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 745 break; 746 m_copydata(m, off, sizeof(th), (caddr_t)&th); 747 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 748 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 749 break; 750 case IPPROTO_UDP: 751 spidx->ul_proto = nxt; 752 if (!needport) 753 break; 754 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 755 break; 756 m_copydata(m, off, sizeof(uh), (caddr_t)&uh); 757 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 758 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 759 break; 760 case IPPROTO_ICMPV6: 761 spidx->ul_proto = nxt; 762 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 763 break; 764 m_copydata(m, off, sizeof(ih), (caddr_t)&ih); 765 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 766 htons((uint16_t)ih.icmp6_type); 767 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 768 htons((uint16_t)ih.icmp6_code); 769 break; 770 default: 771 /* XXX Intermediate headers??? */ 772 spidx->ul_proto = nxt; 773 break; 774 } 775 } 776 777 /* Assumes that m is sane. */ 778 static int 779 ipsec6_setspidx_ipaddr(const struct mbuf *m, struct secpolicyindex *spidx) 780 { 781 struct ip6_hdr ip6buf; 782 const struct ip6_hdr *ip6 = NULL; 783 struct sockaddr_in6 *sin6; 784 785 if (m->m_len >= sizeof(*ip6)) 786 ip6 = mtod(m, const struct ip6_hdr *); 787 else { 788 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf); 789 ip6 = &ip6buf; 790 } 791 792 sin6 = (struct sockaddr_in6 *)&spidx->src; 793 bzero(sin6, sizeof(*sin6)); 794 sin6->sin6_family = AF_INET6; 795 sin6->sin6_len = sizeof(struct sockaddr_in6); 796 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src)); 797 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 798 sin6->sin6_addr.s6_addr16[1] = 0; 799 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 800 } 801 spidx->prefs = sizeof(struct in6_addr) << 3; 802 803 sin6 = (struct sockaddr_in6 *)&spidx->dst; 804 bzero(sin6, sizeof(*sin6)); 805 sin6->sin6_family = AF_INET6; 806 sin6->sin6_len = sizeof(struct sockaddr_in6); 807 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst)); 808 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 809 sin6->sin6_addr.s6_addr16[1] = 0; 810 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 811 } 812 spidx->prefd = sizeof(struct in6_addr) << 3; 813 814 return (0); 815 } 816 #endif 817 818 int 819 ipsec_run_hhooks(struct ipsec_ctx_data *ctx, int type) 820 { 821 int idx; 822 823 switch (ctx->af) { 824 #ifdef INET 825 case AF_INET: 826 idx = HHOOK_IPSEC_INET; 827 break; 828 #endif 829 #ifdef INET6 830 case AF_INET6: 831 idx = HHOOK_IPSEC_INET6; 832 break; 833 #endif 834 default: 835 return (EPFNOSUPPORT); 836 } 837 if (type == HHOOK_TYPE_IPSEC_IN) 838 HHOOKS_RUN_IF(V_ipsec_hhh_in[idx], ctx, NULL); 839 else 840 HHOOKS_RUN_IF(V_ipsec_hhh_out[idx], ctx, NULL); 841 if (*ctx->mp == NULL) 842 return (EACCES); 843 return (0); 844 } 845 846 static void 847 ipsec_delpcbpolicy(struct inpcbpolicy *p) 848 { 849 850 free(p, M_IPSEC_INPCB); 851 } 852 853 /* Initialize policy in PCB. */ 854 int 855 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp) 856 { 857 struct inpcbpolicy *new; 858 859 /* Sanity check. */ 860 if (so == NULL || pcb_sp == NULL) 861 panic("%s: NULL pointer was passed.\n", __func__); 862 863 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy), 864 M_IPSEC_INPCB, M_NOWAIT|M_ZERO); 865 if (new == NULL) { 866 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 867 return (ENOBUFS); 868 } 869 870 new->priv = IPSEC_IS_PRIVILEGED_SO(so); 871 872 if ((new->sp_in = KEY_NEWSP()) == NULL) { 873 ipsec_delpcbpolicy(new); 874 return (ENOBUFS); 875 } 876 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 877 if ((new->sp_out = KEY_NEWSP()) == NULL) { 878 KEY_FREESP(&new->sp_in); 879 ipsec_delpcbpolicy(new); 880 return (ENOBUFS); 881 } 882 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 883 *pcb_sp = new; 884 885 return (0); 886 } 887 888 /* Copy old IPsec policy into new. */ 889 int 890 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new) 891 { 892 struct secpolicy *sp; 893 894 sp = ipsec_deepcopy_policy(old->sp_in); 895 if (sp) { 896 KEY_FREESP(&new->sp_in); 897 new->sp_in = sp; 898 } else 899 return (ENOBUFS); 900 901 sp = ipsec_deepcopy_policy(old->sp_out); 902 if (sp) { 903 KEY_FREESP(&new->sp_out); 904 new->sp_out = sp; 905 } else 906 return (ENOBUFS); 907 908 new->priv = old->priv; 909 910 return (0); 911 } 912 913 struct ipsecrequest * 914 ipsec_newisr(void) 915 { 916 struct ipsecrequest *p; 917 918 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO); 919 if (p != NULL) 920 IPSECREQUEST_LOCK_INIT(p); 921 return (p); 922 } 923 924 void 925 ipsec_delisr(struct ipsecrequest *p) 926 { 927 928 IPSECREQUEST_LOCK_DESTROY(p); 929 free(p, M_IPSEC_SR); 930 } 931 932 /* Deep-copy a policy in PCB. */ 933 static struct secpolicy * 934 ipsec_deepcopy_policy(struct secpolicy *src) 935 { 936 struct ipsecrequest *newchain = NULL; 937 struct ipsecrequest *p; 938 struct ipsecrequest **q; 939 struct ipsecrequest *r; 940 struct secpolicy *dst; 941 942 if (src == NULL) 943 return (NULL); 944 dst = KEY_NEWSP(); 945 if (dst == NULL) 946 return (NULL); 947 948 /* 949 * Deep-copy IPsec request chain. This is required since struct 950 * ipsecrequest is not reference counted. 951 */ 952 q = &newchain; 953 for (p = src->req; p; p = p->next) { 954 *q = ipsec_newisr(); 955 if (*q == NULL) 956 goto fail; 957 (*q)->saidx.proto = p->saidx.proto; 958 (*q)->saidx.mode = p->saidx.mode; 959 (*q)->level = p->level; 960 (*q)->saidx.reqid = p->saidx.reqid; 961 962 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src)); 963 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst)); 964 965 (*q)->sp = dst; 966 967 q = &((*q)->next); 968 } 969 970 dst->req = newchain; 971 dst->policy = src->policy; 972 /* Do not touch the refcnt fields. */ 973 974 return (dst); 975 976 fail: 977 for (p = newchain; p; p = r) { 978 r = p->next; 979 ipsec_delisr(p); 980 p = NULL; 981 } 982 KEY_FREESP(&dst); 983 return (NULL); 984 } 985 986 /* Set policy and IPsec request if present. */ 987 static int 988 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname, 989 caddr_t request, size_t len, struct ucred *cred) 990 { 991 struct sadb_x_policy *xpl; 992 struct secpolicy *newsp = NULL; 993 int error; 994 995 /* Sanity check. */ 996 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL) 997 return (EINVAL); 998 if (len < sizeof(*xpl)) 999 return (EINVAL); 1000 xpl = (struct sadb_x_policy *)request; 1001 1002 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1003 printf("%s: passed policy\n", __func__); 1004 kdebug_sadb_x_policy((struct sadb_ext *)xpl)); 1005 1006 /* Check policy type. */ 1007 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */ 1008 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 1009 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1010 return (EINVAL); 1011 1012 /* Check privileged socket. */ 1013 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1014 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0); 1015 if (error) 1016 return (EACCES); 1017 } 1018 1019 /* Allocating new SP entry. */ 1020 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1021 return (error); 1022 1023 /* Clear old SP and set new SP. */ 1024 KEY_FREESP(pcb_sp); 1025 *pcb_sp = newsp; 1026 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1027 printf("%s: new policy\n", __func__); 1028 kdebug_secpolicy(newsp)); 1029 1030 return (0); 1031 } 1032 1033 int 1034 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request, 1035 size_t len, struct ucred *cred) 1036 { 1037 struct sadb_x_policy *xpl; 1038 struct secpolicy **pcb_sp; 1039 1040 /* Sanity check. */ 1041 if (inp == NULL || request == NULL) 1042 return (EINVAL); 1043 if (len < sizeof(*xpl)) 1044 return (EINVAL); 1045 xpl = (struct sadb_x_policy *)request; 1046 1047 /* Select direction. */ 1048 switch (xpl->sadb_x_policy_dir) { 1049 case IPSEC_DIR_INBOUND: 1050 pcb_sp = &inp->inp_sp->sp_in; 1051 break; 1052 case IPSEC_DIR_OUTBOUND: 1053 pcb_sp = &inp->inp_sp->sp_out; 1054 break; 1055 default: 1056 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1057 xpl->sadb_x_policy_dir)); 1058 return (EINVAL); 1059 } 1060 1061 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred)); 1062 } 1063 1064 int 1065 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len, 1066 struct mbuf **mp) 1067 { 1068 struct sadb_x_policy *xpl; 1069 struct secpolicy *pcb_sp; 1070 1071 /* Sanity check. */ 1072 if (inp == NULL || request == NULL || mp == NULL) 1073 return (EINVAL); 1074 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 1075 if (len < sizeof(*xpl)) 1076 return (EINVAL); 1077 xpl = (struct sadb_x_policy *)request; 1078 1079 /* Select direction. */ 1080 switch (xpl->sadb_x_policy_dir) { 1081 case IPSEC_DIR_INBOUND: 1082 pcb_sp = inp->inp_sp->sp_in; 1083 break; 1084 case IPSEC_DIR_OUTBOUND: 1085 pcb_sp = inp->inp_sp->sp_out; 1086 break; 1087 default: 1088 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1089 xpl->sadb_x_policy_dir)); 1090 return (EINVAL); 1091 } 1092 1093 /* Sanity check. Should be an IPSEC_ASSERT. */ 1094 if (pcb_sp == NULL) 1095 return (EINVAL); 1096 1097 *mp = key_sp2msg(pcb_sp); 1098 if (!*mp) { 1099 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 1100 return (ENOBUFS); 1101 } 1102 1103 (*mp)->m_type = MT_DATA; 1104 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1105 printf("%s:\n", __func__); kdebug_mbuf(*mp)); 1106 1107 return (0); 1108 } 1109 1110 /* Delete policy in PCB. */ 1111 int 1112 ipsec_delete_pcbpolicy(struct inpcb *inp) 1113 { 1114 IPSEC_ASSERT(inp != NULL, ("null inp")); 1115 1116 if (inp->inp_sp == NULL) 1117 return (0); 1118 1119 if (inp->inp_sp->sp_in != NULL) 1120 KEY_FREESP(&inp->inp_sp->sp_in); 1121 1122 if (inp->inp_sp->sp_out != NULL) 1123 KEY_FREESP(&inp->inp_sp->sp_out); 1124 1125 ipsec_delpcbpolicy(inp->inp_sp); 1126 inp->inp_sp = NULL; 1127 1128 return (0); 1129 } 1130 1131 /* 1132 * Return current level. 1133 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1134 */ 1135 u_int 1136 ipsec_get_reqlevel(struct ipsecrequest *isr) 1137 { 1138 u_int level = 0; 1139 u_int esp_trans_deflev, esp_net_deflev; 1140 u_int ah_trans_deflev, ah_net_deflev; 1141 1142 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument")); 1143 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1144 ("af family mismatch, src %u, dst %u", 1145 isr->sp->spidx.src.sa.sa_family, 1146 isr->sp->spidx.dst.sa.sa_family)); 1147 1148 /* XXX Note that we have ipseclog() expanded here - code sync issue. */ 1149 #define IPSEC_CHECK_DEFAULT(lev) \ 1150 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1151 && (lev) != IPSEC_LEVEL_UNIQUE) \ 1152 ? (V_ipsec_debug \ 1153 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\ 1154 (lev), IPSEC_LEVEL_REQUIRE) \ 1155 : 0), \ 1156 (lev) = IPSEC_LEVEL_REQUIRE, \ 1157 (lev) \ 1158 : (lev)) 1159 1160 /* Set default level. */ 1161 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1162 #ifdef INET 1163 case AF_INET: 1164 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev); 1165 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev); 1166 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev); 1167 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev); 1168 break; 1169 #endif 1170 #ifdef INET6 1171 case AF_INET6: 1172 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev); 1173 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev); 1174 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev); 1175 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev); 1176 break; 1177 #endif /* INET6 */ 1178 default: 1179 panic("%s: unknown af %u", 1180 __func__, isr->sp->spidx.src.sa.sa_family); 1181 } 1182 1183 #undef IPSEC_CHECK_DEFAULT 1184 1185 /* Set level. */ 1186 switch (isr->level) { 1187 case IPSEC_LEVEL_DEFAULT: 1188 switch (isr->saidx.proto) { 1189 case IPPROTO_ESP: 1190 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1191 level = esp_net_deflev; 1192 else 1193 level = esp_trans_deflev; 1194 break; 1195 case IPPROTO_AH: 1196 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1197 level = ah_net_deflev; 1198 else 1199 level = ah_trans_deflev; 1200 break; 1201 case IPPROTO_IPCOMP: 1202 /* 1203 * We don't really care, as IPcomp document says that 1204 * we shouldn't compress small packets. 1205 */ 1206 level = IPSEC_LEVEL_USE; 1207 break; 1208 default: 1209 panic("%s: Illegal protocol defined %u\n", __func__, 1210 isr->saidx.proto); 1211 } 1212 break; 1213 1214 case IPSEC_LEVEL_USE: 1215 case IPSEC_LEVEL_REQUIRE: 1216 level = isr->level; 1217 break; 1218 case IPSEC_LEVEL_UNIQUE: 1219 level = IPSEC_LEVEL_REQUIRE; 1220 break; 1221 1222 default: 1223 panic("%s: Illegal IPsec level %u\n", __func__, isr->level); 1224 } 1225 1226 return (level); 1227 } 1228 1229 /* 1230 * Check security policy requirements against the actual 1231 * packet contents. Return one if the packet should be 1232 * reject as "invalid"; otherwiser return zero to have the 1233 * packet treated as "valid". 1234 * 1235 * OUT: 1236 * 0: valid 1237 * 1: invalid 1238 */ 1239 static int 1240 ipsec_in_reject(struct secpolicy *sp, const struct mbuf *m) 1241 { 1242 struct ipsecrequest *isr; 1243 int need_auth; 1244 1245 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1246 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1247 1248 /* Check policy. */ 1249 switch (sp->policy) { 1250 case IPSEC_POLICY_DISCARD: 1251 return (1); 1252 case IPSEC_POLICY_BYPASS: 1253 case IPSEC_POLICY_NONE: 1254 return (0); 1255 } 1256 1257 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1258 ("invalid policy %u", sp->policy)); 1259 1260 /* XXX Should compare policy against IPsec header history. */ 1261 1262 need_auth = 0; 1263 for (isr = sp->req; isr != NULL; isr = isr->next) { 1264 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1265 continue; 1266 switch (isr->saidx.proto) { 1267 case IPPROTO_ESP: 1268 if ((m->m_flags & M_DECRYPTED) == 0) { 1269 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1270 printf("%s: ESP m_flags:%x\n", __func__, 1271 m->m_flags)); 1272 return (1); 1273 } 1274 1275 if (!need_auth && 1276 isr->sav != NULL && 1277 isr->sav->tdb_authalgxform != NULL && 1278 (m->m_flags & M_AUTHIPDGM) == 0) { 1279 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1280 printf("%s: ESP/AH m_flags:%x\n", __func__, 1281 m->m_flags)); 1282 return (1); 1283 } 1284 break; 1285 case IPPROTO_AH: 1286 need_auth = 1; 1287 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1288 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1289 printf("%s: AH m_flags:%x\n", __func__, 1290 m->m_flags)); 1291 return (1); 1292 } 1293 break; 1294 case IPPROTO_IPCOMP: 1295 /* 1296 * We don't really care, as IPcomp document 1297 * says that we shouldn't compress small 1298 * packets. IPComp policy should always be 1299 * treated as being in "use" level. 1300 */ 1301 break; 1302 } 1303 } 1304 return (0); /* Valid. */ 1305 } 1306 1307 /* 1308 * Non zero return value means security policy DISCARD or policy violation. 1309 */ 1310 static int 1311 ipsec46_in_reject(const struct mbuf *m, struct inpcb *inp) 1312 { 1313 struct secpolicy *sp; 1314 int error; 1315 int result; 1316 1317 if (!key_havesp(IPSEC_DIR_INBOUND)) 1318 return 0; 1319 1320 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1321 1322 /* Get SP for this packet. */ 1323 if (inp == NULL) 1324 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, &error); 1325 else 1326 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error); 1327 1328 if (sp != NULL) { 1329 result = ipsec_in_reject(sp, m); 1330 KEY_FREESP(&sp); 1331 } else { 1332 result = 1; /* treat errors as policy violation */ 1333 } 1334 return (result); 1335 } 1336 1337 /* 1338 * Check AH/ESP integrity. 1339 * This function is called from tcp_input(), udp_input(), 1340 * and {ah,esp}4_input for tunnel mode. 1341 */ 1342 int 1343 ipsec4_in_reject(const struct mbuf *m, struct inpcb *inp) 1344 { 1345 int result; 1346 1347 result = ipsec46_in_reject(m, inp); 1348 if (result) 1349 IPSECSTAT_INC(ips_in_polvio); 1350 1351 return (result); 1352 } 1353 1354 #ifdef INET6 1355 /* 1356 * Check AH/ESP integrity. 1357 * This function is called from tcp6_input(), udp6_input(), 1358 * and {ah,esp}6_input for tunnel mode. 1359 */ 1360 int 1361 ipsec6_in_reject(const struct mbuf *m, struct inpcb *inp) 1362 { 1363 int result; 1364 1365 result = ipsec46_in_reject(m, inp); 1366 if (result) 1367 IPSEC6STAT_INC(ips_in_polvio); 1368 1369 return (result); 1370 } 1371 #endif 1372 1373 /* 1374 * Compute the byte size to be occupied by IPsec header. 1375 * In case it is tunnelled, it includes the size of outer IP header. 1376 * NOTE: SP passed is freed in this function. 1377 */ 1378 static size_t 1379 ipsec_hdrsiz_internal(struct secpolicy *sp) 1380 { 1381 struct ipsecrequest *isr; 1382 size_t size; 1383 1384 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1385 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1386 1387 switch (sp->policy) { 1388 case IPSEC_POLICY_DISCARD: 1389 case IPSEC_POLICY_BYPASS: 1390 case IPSEC_POLICY_NONE: 1391 return (0); 1392 } 1393 1394 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1395 ("invalid policy %u", sp->policy)); 1396 1397 size = 0; 1398 for (isr = sp->req; isr != NULL; isr = isr->next) { 1399 size_t clen = 0; 1400 1401 switch (isr->saidx.proto) { 1402 case IPPROTO_ESP: 1403 clen = esp_hdrsiz(isr->sav); 1404 break; 1405 case IPPROTO_AH: 1406 clen = ah_hdrsiz(isr->sav); 1407 break; 1408 case IPPROTO_IPCOMP: 1409 clen = sizeof(struct ipcomp); 1410 break; 1411 } 1412 1413 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1414 switch (isr->saidx.dst.sa.sa_family) { 1415 case AF_INET: 1416 clen += sizeof(struct ip); 1417 break; 1418 #ifdef INET6 1419 case AF_INET6: 1420 clen += sizeof(struct ip6_hdr); 1421 break; 1422 #endif 1423 default: 1424 ipseclog((LOG_ERR, "%s: unknown AF %d in " 1425 "IPsec tunnel SA\n", __func__, 1426 ((struct sockaddr *)&isr->saidx.dst)->sa_family)); 1427 break; 1428 } 1429 } 1430 size += clen; 1431 } 1432 1433 return (size); 1434 } 1435 1436 /* 1437 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(), 1438 * disabled ip6_ipsec_mtu() and ip6_forward(). 1439 */ 1440 size_t 1441 ipsec_hdrsiz(const struct mbuf *m, u_int dir, struct inpcb *inp) 1442 { 1443 struct secpolicy *sp; 1444 int error; 1445 size_t size; 1446 1447 if (!key_havesp(dir)) 1448 return 0; 1449 1450 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1451 1452 /* Get SP for this packet. */ 1453 if (inp == NULL) 1454 sp = ipsec_getpolicybyaddr(m, dir, &error); 1455 else 1456 sp = ipsec_getpolicybysock(m, dir, inp, &error); 1457 1458 if (sp != NULL) { 1459 size = ipsec_hdrsiz_internal(sp); 1460 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1461 printf("%s: size:%lu.\n", __func__, 1462 (unsigned long)size)); 1463 1464 KEY_FREESP(&sp); 1465 } else { 1466 size = 0; /* XXX Should be panic? 1467 * -> No, we are called w/o knowing if 1468 * IPsec processing is needed. */ 1469 } 1470 return (size); 1471 } 1472 1473 /* 1474 * Check the variable replay window. 1475 * ipsec_chkreplay() performs replay check before ICV verification. 1476 * ipsec_updatereplay() updates replay bitmap. This must be called after 1477 * ICV verification (it also performs replay check, which is usually done 1478 * beforehand). 1479 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1480 * 1481 * Based on RFC 6479. Blocks are 32 bits unsigned integers 1482 */ 1483 1484 #define IPSEC_BITMAP_INDEX_MASK(w) (w - 1) 1485 #define IPSEC_REDUNDANT_BIT_SHIFTS 5 1486 #define IPSEC_REDUNDANT_BITS (1 << IPSEC_REDUNDANT_BIT_SHIFTS) 1487 #define IPSEC_BITMAP_LOC_MASK (IPSEC_REDUNDANT_BITS - 1) 1488 1489 int 1490 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav) 1491 { 1492 const struct secreplay *replay; 1493 u_int32_t wsizeb; /* Constant: window size. */ 1494 int ret, index, bit_location; 1495 1496 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1497 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1498 1499 SECASVAR_LOCK(sav); 1500 1501 ret = 0; 1502 replay = sav->replay; 1503 1504 /* No need to check replay if disabled. */ 1505 if (replay->wsize == 0) 1506 goto allowed; 1507 1508 /* Constant. */ 1509 wsizeb = replay->wsize << 3; 1510 1511 /* Sequence number of 0 is invalid. */ 1512 if (seq == 0) 1513 goto end; 1514 1515 /* First time is always okay. */ 1516 if (replay->count == 0) 1517 goto allowed; 1518 1519 /* Larger sequences are okay. */ 1520 if (seq > replay->lastseq) 1521 goto allowed; 1522 1523 /* Over range to check, i.e. too old or wrapped. */ 1524 if (replay->lastseq - seq >= wsizeb) 1525 goto end; 1526 1527 /* The sequence is inside the sliding window 1528 * now check the bit in the bitmap 1529 * bit location only depends on the sequence number 1530 */ 1531 bit_location = seq & IPSEC_BITMAP_LOC_MASK; 1532 index = (seq >> IPSEC_REDUNDANT_BIT_SHIFTS) 1533 & IPSEC_BITMAP_INDEX_MASK(replay->bitmap_size); 1534 1535 /* This packet already seen? */ 1536 if ((replay->bitmap)[index] & (1 << bit_location)) 1537 goto end; 1538 1539 allowed: 1540 ret = 1; 1541 end: 1542 SECASVAR_UNLOCK(sav); 1543 1544 return (ret); 1545 } 1546 1547 /* 1548 * Check replay counter whether to update or not. 1549 * OUT: 0: OK 1550 * 1: NG 1551 */ 1552 int 1553 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav) 1554 { 1555 char buf[128]; 1556 struct secreplay *replay; 1557 u_int32_t wsizeb; /* Constant: window size. */ 1558 int ret, diff, index, bit_location; 1559 1560 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1561 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1562 1563 SECASVAR_LOCK(sav); 1564 1565 ret = 1; 1566 replay = sav->replay; 1567 1568 if (replay->wsize == 0) 1569 goto ok; /* No need to check replay. */ 1570 1571 /* Constant. */ 1572 wsizeb = replay->wsize << 3; 1573 1574 /* Sequence number of 0 is invalid. */ 1575 if (seq == 0) 1576 goto end; 1577 1578 /* The packet is too old, no need to update */ 1579 if (wsizeb + seq < replay->lastseq) 1580 goto ok; 1581 1582 /* Now update the bit */ 1583 index = (seq >> IPSEC_REDUNDANT_BIT_SHIFTS); 1584 1585 /* First check if the sequence number is in the range */ 1586 if (seq > replay->lastseq) { 1587 int id; 1588 int index_cur = replay->lastseq >> IPSEC_REDUNDANT_BIT_SHIFTS; 1589 1590 diff = index - index_cur; 1591 if (diff > replay->bitmap_size) { 1592 /* something unusual in this case */ 1593 diff = replay->bitmap_size; 1594 } 1595 1596 for (id = 0; id < diff; ++id) { 1597 replay->bitmap[(id + index_cur + 1) 1598 & IPSEC_BITMAP_INDEX_MASK(replay->bitmap_size)] = 0; 1599 } 1600 1601 replay->lastseq = seq; 1602 } 1603 1604 index &= IPSEC_BITMAP_INDEX_MASK(replay->bitmap_size); 1605 bit_location = seq & IPSEC_BITMAP_LOC_MASK; 1606 1607 /* this packet has already been received */ 1608 if (replay->bitmap[index] & (1 << bit_location)) 1609 goto end; 1610 1611 replay->bitmap[index] |= (1 << bit_location); 1612 1613 ok: 1614 if (replay->count == ~0) { 1615 1616 /* Set overflow flag. */ 1617 replay->overflow++; 1618 1619 /* Don't increment, no more packets accepted. */ 1620 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 1621 goto end; 1622 1623 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1624 __func__, replay->overflow, 1625 ipsec_logsastr(sav, buf, sizeof(buf)))); 1626 } 1627 1628 ret = 0; 1629 1630 end: 1631 SECASVAR_UNLOCK(sav); 1632 return (ret); 1633 } 1634 1635 /* Return a printable string for the address. */ 1636 char* 1637 ipsec_address(union sockaddr_union* sa, char *buf, socklen_t size) 1638 { 1639 1640 switch (sa->sa.sa_family) { 1641 #ifdef INET 1642 case AF_INET: 1643 return (inet_ntop(AF_INET, &sa->sin.sin_addr, buf, size)); 1644 #endif /* INET */ 1645 #ifdef INET6 1646 case AF_INET6: 1647 return (inet_ntop(AF_INET6, &sa->sin6.sin6_addr, buf, size)); 1648 #endif /* INET6 */ 1649 default: 1650 return ("(unknown address family)"); 1651 } 1652 } 1653 1654 char * 1655 ipsec_logsastr(struct secasvar *sav, char *buf, size_t size) 1656 { 1657 char sbuf[INET6_ADDRSTRLEN], dbuf[INET6_ADDRSTRLEN]; 1658 1659 IPSEC_ASSERT(sav->sah->saidx.src.sa.sa_family == 1660 sav->sah->saidx.dst.sa.sa_family, ("address family mismatch")); 1661 1662 snprintf(buf, size, "SA(SPI=%08lx src=%s dst=%s)", 1663 (u_long)ntohl(sav->spi), 1664 ipsec_address(&sav->sah->saidx.src, sbuf, sizeof(sbuf)), 1665 ipsec_address(&sav->sah->saidx.dst, dbuf, sizeof(dbuf))); 1666 return (buf); 1667 } 1668 1669 void 1670 ipsec_dumpmbuf(const struct mbuf *m) 1671 { 1672 const u_char *p; 1673 int totlen; 1674 int i; 1675 1676 totlen = 0; 1677 printf("---\n"); 1678 while (m) { 1679 p = mtod(m, const u_char *); 1680 for (i = 0; i < m->m_len; i++) { 1681 printf("%02x ", p[i]); 1682 totlen++; 1683 if (totlen % 16 == 0) 1684 printf("\n"); 1685 } 1686 m = m->m_next; 1687 } 1688 if (totlen % 16 != 0) 1689 printf("\n"); 1690 printf("---\n"); 1691 } 1692 1693 static void 1694 def_policy_init(const void *unused __unused) 1695 { 1696 1697 bzero(&V_def_policy, sizeof(struct secpolicy)); 1698 V_def_policy.policy = IPSEC_POLICY_NONE; 1699 V_def_policy.refcnt = 1; 1700 } 1701 VNET_SYSINIT(def_policy_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST, 1702 def_policy_init, NULL); 1703 1704 1705 /* XXX This stuff doesn't belong here... */ 1706 1707 static struct xformsw* xforms = NULL; 1708 1709 /* 1710 * Register a transform; typically at system startup. 1711 */ 1712 void 1713 xform_register(struct xformsw* xsp) 1714 { 1715 1716 xsp->xf_next = xforms; 1717 xforms = xsp; 1718 } 1719 1720 /* 1721 * Initialize transform support in an sav. 1722 */ 1723 int 1724 xform_init(struct secasvar *sav, int xftype) 1725 { 1726 struct xformsw *xsp; 1727 1728 if (sav->tdb_xform != NULL) /* Previously initialized. */ 1729 return (0); 1730 for (xsp = xforms; xsp; xsp = xsp->xf_next) 1731 if (xsp->xf_type == xftype) 1732 return ((*xsp->xf_init)(sav, xsp)); 1733 return (EINVAL); 1734 } 1735