ipsec.c revision 1.138
1 /* $NetBSD: ipsec.c,v 1.138 2018/02/26 08:50:25 maxv Exp $ */ 2 /* $FreeBSD: src/sys/netipsec/ipsec.c,v 1.2.2.2 2003/07/01 01:38:13 sam Exp $ */ 3 /* $KAME: ipsec.c,v 1.103 2001/05/24 07:14:18 sakane Exp $ */ 4 5 /* 6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the project nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 __KERNEL_RCSID(0, "$NetBSD: ipsec.c,v 1.138 2018/02/26 08:50:25 maxv Exp $"); 36 37 /* 38 * IPsec controller part. 39 */ 40 41 #if defined(_KERNEL_OPT) 42 #include "opt_inet.h" 43 #include "opt_ipsec.h" 44 #endif 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/mbuf.h> 49 #include <sys/domain.h> 50 #include <sys/protosw.h> 51 #include <sys/socket.h> 52 #include <sys/socketvar.h> 53 #include <sys/errno.h> 54 #include <sys/time.h> 55 #include <sys/kernel.h> 56 #include <sys/syslog.h> 57 #include <sys/sysctl.h> 58 #include <sys/proc.h> 59 #include <sys/kauth.h> 60 #include <sys/cpu.h> 61 #include <sys/kmem.h> 62 #include <sys/pserialize.h> 63 64 #include <net/if.h> 65 #include <net/route.h> 66 67 #include <netinet/in.h> 68 #include <netinet/in_systm.h> 69 #include <netinet/ip.h> 70 #include <netinet/ip_var.h> 71 #include <netinet/in_var.h> 72 #include <netinet/udp.h> 73 #include <netinet/udp_var.h> 74 #include <netinet/tcp.h> 75 #include <netinet/udp.h> 76 #include <netinet/ip_icmp.h> 77 #include <netinet/ip_private.h> 78 79 #include <netinet/ip6.h> 80 #ifdef INET6 81 #include <netinet6/ip6_var.h> 82 #endif 83 #include <netinet/in_pcb.h> 84 #ifdef INET6 85 #include <netinet6/in6_pcb.h> 86 #include <netinet/icmp6.h> 87 #endif 88 89 #include <netipsec/ipsec.h> 90 #include <netipsec/ipsec_var.h> 91 #include <netipsec/ipsec_private.h> 92 #ifdef INET6 93 #include <netipsec/ipsec6.h> 94 #endif 95 #include <netipsec/ah_var.h> 96 #include <netipsec/esp_var.h> 97 #include <netipsec/ipcomp.h> /*XXX*/ 98 #include <netipsec/ipcomp_var.h> 99 100 #include <netipsec/key.h> 101 #include <netipsec/keydb.h> 102 #include <netipsec/key_debug.h> 103 104 #include <netipsec/xform.h> 105 106 int ipsec_used = 0; 107 int ipsec_enabled = 1; 108 109 #ifdef IPSEC_DEBUG 110 int ipsec_debug = 1; 111 112 /* 113 * When set to 1, IPsec will send packets with the same sequence number. 114 * This allows to verify if the other side has proper replay attacks detection. 115 */ 116 int ipsec_replay = 0; 117 118 /* 119 * When set 1, IPsec will send packets with corrupted HMAC. 120 * This allows to verify if the other side properly detects modified packets. 121 */ 122 int ipsec_integrity = 0; 123 #else 124 int ipsec_debug = 0; 125 #endif 126 127 percpu_t *ipsecstat_percpu; 128 129 int ip4_ah_offsetmask = 0; /* maybe IP_DF? */ 130 int ip4_ipsec_dfbit = 2; /* DF bit on encap. 0: clear 1: set 2: copy */ 131 int ip4_esp_trans_deflev = IPSEC_LEVEL_USE; 132 int ip4_esp_net_deflev = IPSEC_LEVEL_USE; 133 int ip4_ah_trans_deflev = IPSEC_LEVEL_USE; 134 int ip4_ah_net_deflev = IPSEC_LEVEL_USE; 135 struct secpolicy ip4_def_policy; 136 int ip4_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 137 138 u_int ipsec_spdgen = 1; /* SPD generation # */ 139 140 static struct secpolicy ipsec_dummy_sp __read_mostly = { 141 .state = IPSEC_SPSTATE_ALIVE, 142 /* If ENTRUST, the dummy SP never be used. See ipsec_getpolicybysock. */ 143 .policy = IPSEC_POLICY_ENTRUST, 144 }; 145 146 static struct secpolicy *ipsec_checkpcbcache(struct mbuf *, 147 struct inpcbpolicy *, int); 148 static int ipsec_fillpcbcache(struct inpcbpolicy *, struct mbuf *, 149 struct secpolicy *, int); 150 static int ipsec_invalpcbcache(struct inpcbpolicy *, int); 151 152 /* 153 * Crypto support requirements: 154 * 155 * 1 require hardware support 156 * -1 require software support 157 * 0 take anything 158 */ 159 int crypto_support = 0; 160 161 static struct secpolicy *ipsec_getpolicybysock(struct mbuf *, u_int, 162 struct inpcb_hdr *, int *); 163 164 #ifdef INET6 165 int ip6_esp_trans_deflev = IPSEC_LEVEL_USE; 166 int ip6_esp_net_deflev = IPSEC_LEVEL_USE; 167 int ip6_ah_trans_deflev = IPSEC_LEVEL_USE; 168 int ip6_ah_net_deflev = IPSEC_LEVEL_USE; 169 struct secpolicy ip6_def_policy; 170 int ip6_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 171 #endif 172 173 static int ipsec4_setspidx_inpcb(struct mbuf *, struct inpcb *); 174 #ifdef INET6 175 static int ipsec6_setspidx_in6pcb(struct mbuf *, struct in6pcb *); 176 #endif 177 static int ipsec_setspidx(struct mbuf *, struct secpolicyindex *, int); 178 static void ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *, int); 179 static int ipsec4_setspidx_ipaddr(struct mbuf *, struct secpolicyindex *); 180 #ifdef INET6 181 static void ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *, int); 182 static int ipsec6_setspidx_ipaddr(struct mbuf *, struct secpolicyindex *); 183 #endif 184 static void ipsec_delpcbpolicy(struct inpcbpolicy *); 185 #if 0 /* unused */ 186 static struct secpolicy *ipsec_deepcopy_policy(const struct secpolicy *); 187 #endif 188 static int ipsec_set_policy(struct secpolicy **, int, const void *, size_t, 189 kauth_cred_t); 190 static int ipsec_get_policy(struct secpolicy *, struct mbuf **); 191 static void ipsec_destroy_policy(struct secpolicy *); 192 static int ipsec_sp_reject(const struct secpolicy *, const struct mbuf *); 193 static void vshiftl(unsigned char *, int, int); 194 static size_t ipsec_sp_hdrsiz(const struct secpolicy *, const struct mbuf *); 195 196 /* 197 * Try to validate and use cached policy on a PCB. 198 */ 199 static struct secpolicy * 200 ipsec_checkpcbcache(struct mbuf *m, struct inpcbpolicy *pcbsp, int dir) 201 { 202 struct secpolicyindex spidx; 203 struct secpolicy *sp = NULL; 204 int s; 205 206 KASSERT(IPSEC_DIR_IS_VALID(dir)); 207 KASSERT(pcbsp != NULL); 208 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 209 KASSERT(inph_locked(pcbsp->sp_inph)); 210 211 /* 212 * Checking the generation and sp->state and taking a reference to an SP 213 * must be in a critical section of pserialize. See key_unlink_sp. 214 */ 215 s = pserialize_read_enter(); 216 /* SPD table change invalidate all the caches. */ 217 if (ipsec_spdgen != pcbsp->sp_cache[dir].cachegen) { 218 ipsec_invalpcbcache(pcbsp, dir); 219 goto out; 220 } 221 sp = pcbsp->sp_cache[dir].cachesp; 222 if (sp == NULL) 223 goto out; 224 if (sp->state != IPSEC_SPSTATE_ALIVE) { 225 sp = NULL; 226 ipsec_invalpcbcache(pcbsp, dir); 227 goto out; 228 } 229 if ((pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) == 0) { 230 /* NB: assume ipsec_setspidx never sleep */ 231 if (ipsec_setspidx(m, &spidx, 1) != 0) { 232 sp = NULL; 233 goto out; 234 } 235 236 /* 237 * We have to make an exact match here since the cached rule 238 * might have lower priority than a rule that would otherwise 239 * have matched the packet. 240 */ 241 if (memcmp(&pcbsp->sp_cache[dir].cacheidx, &spidx, 242 sizeof(spidx))) { 243 sp = NULL; 244 goto out; 245 } 246 } else { 247 /* 248 * The pcb is connected, and the L4 code is sure that: 249 * - outgoing side uses inp_[lf]addr 250 * - incoming side looks up policy after inpcb lookup 251 * and address pair is know to be stable. We do not need 252 * to generate spidx again, nor check the address match again. 253 * 254 * For IPv4/v6 SOCK_STREAM sockets, this assumptions holds 255 * and there are calls to ipsec_pcbconn() from in_pcbconnect(). 256 */ 257 } 258 259 sp->lastused = time_second; 260 KEY_SP_REF(sp); 261 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 262 "DP cause refcnt++:%d SP:%p\n", 263 key_sp_refcnt(sp), pcbsp->sp_cache[dir].cachesp); 264 out: 265 pserialize_read_exit(s); 266 return sp; 267 } 268 269 static int 270 ipsec_fillpcbcache(struct inpcbpolicy *pcbsp, struct mbuf *m, 271 struct secpolicy *sp, int dir) 272 { 273 274 KASSERT(IPSEC_DIR_IS_INOROUT(dir)); 275 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 276 KASSERT(inph_locked(pcbsp->sp_inph)); 277 278 pcbsp->sp_cache[dir].cachesp = NULL; 279 pcbsp->sp_cache[dir].cachehint = IPSEC_PCBHINT_UNKNOWN; 280 if (ipsec_setspidx(m, &pcbsp->sp_cache[dir].cacheidx, 1) != 0) { 281 return EINVAL; 282 } 283 pcbsp->sp_cache[dir].cachesp = sp; 284 if (pcbsp->sp_cache[dir].cachesp) { 285 /* 286 * If the PCB is connected, we can remember a hint to 287 * possibly short-circuit IPsec processing in other places. 288 */ 289 if (pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) { 290 switch (pcbsp->sp_cache[dir].cachesp->policy) { 291 case IPSEC_POLICY_NONE: 292 case IPSEC_POLICY_BYPASS: 293 pcbsp->sp_cache[dir].cachehint = 294 IPSEC_PCBHINT_NO; 295 break; 296 default: 297 pcbsp->sp_cache[dir].cachehint = 298 IPSEC_PCBHINT_YES; 299 } 300 } 301 } 302 pcbsp->sp_cache[dir].cachegen = ipsec_spdgen; 303 304 return 0; 305 } 306 307 static int 308 ipsec_invalpcbcache(struct inpcbpolicy *pcbsp, int dir) 309 { 310 int i; 311 312 KASSERT(inph_locked(pcbsp->sp_inph)); 313 314 for (i = IPSEC_DIR_INBOUND; i <= IPSEC_DIR_OUTBOUND; i++) { 315 if (dir != IPSEC_DIR_ANY && i != dir) 316 continue; 317 pcbsp->sp_cache[i].cachesp = NULL; 318 pcbsp->sp_cache[i].cachehint = IPSEC_PCBHINT_UNKNOWN; 319 pcbsp->sp_cache[i].cachegen = 0; 320 memset(&pcbsp->sp_cache[i].cacheidx, 0, 321 sizeof(pcbsp->sp_cache[i].cacheidx)); 322 } 323 return 0; 324 } 325 326 void 327 ipsec_pcbconn(struct inpcbpolicy *pcbsp) 328 { 329 330 KASSERT(inph_locked(pcbsp->sp_inph)); 331 332 pcbsp->sp_cacheflags |= IPSEC_PCBSP_CONNECTED; 333 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 334 } 335 336 void 337 ipsec_pcbdisconn(struct inpcbpolicy *pcbsp) 338 { 339 340 KASSERT(inph_locked(pcbsp->sp_inph)); 341 342 pcbsp->sp_cacheflags &= ~IPSEC_PCBSP_CONNECTED; 343 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 344 } 345 346 void 347 ipsec_invalpcbcacheall(void) 348 { 349 350 if (ipsec_spdgen == UINT_MAX) 351 ipsec_spdgen = 1; 352 else 353 ipsec_spdgen++; 354 } 355 356 /* 357 * Return a held reference to the default SP. 358 */ 359 static struct secpolicy * 360 key_get_default_sp(int af, const char *where, int tag) 361 { 362 struct secpolicy *sp; 363 364 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP from %s:%u\n", where, tag); 365 366 switch(af) { 367 case AF_INET: 368 sp = &ip4_def_policy; 369 break; 370 #ifdef INET6 371 case AF_INET6: 372 sp = &ip6_def_policy; 373 break; 374 #endif 375 default: 376 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 377 "unexpected protocol family %u\n", af); 378 return NULL; 379 } 380 381 if (sp->policy != IPSEC_POLICY_DISCARD && 382 sp->policy != IPSEC_POLICY_NONE) { 383 IPSECLOG(LOG_INFO, "fixed system default policy: %d->%d\n", 384 sp->policy, IPSEC_POLICY_NONE); 385 sp->policy = IPSEC_POLICY_NONE; 386 } 387 KEY_SP_REF(sp); 388 389 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP returns SP:%p (%u)\n", 390 sp, key_sp_refcnt(sp)); 391 return sp; 392 } 393 394 #define KEY_GET_DEFAULT_SP(af) \ 395 key_get_default_sp((af), __func__, __LINE__) 396 397 /* 398 * For OUTBOUND packet having a socket. Searching SPD for packet, 399 * and return a pointer to SP. 400 * OUT: NULL: no apropreate SP found, the following value is set to error. 401 * 0 : bypass 402 * EACCES : discard packet. 403 * ENOENT : ipsec_acquire() in progress, maybe. 404 * others : error occurred. 405 * others: a pointer to SP 406 * 407 * NOTE: IPv6 mapped address concern is implemented here. 408 */ 409 static struct secpolicy * 410 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb_hdr *inph, 411 int *error) 412 { 413 struct inpcbpolicy *pcbsp = NULL; 414 struct secpolicy *currsp = NULL; /* policy on socket */ 415 struct secpolicy *sp; 416 int af; 417 418 KASSERT(m != NULL); 419 KASSERT(inph != NULL); 420 KASSERT(error != NULL); 421 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 422 423 KASSERT(inph->inph_socket != NULL); 424 KASSERT(inph_locked(inph)); 425 426 /* XXX FIXME inpcb/in6pcb vs socket*/ 427 af = inph->inph_af; 428 KASSERTMSG(af == AF_INET || af == AF_INET6, 429 "unexpected protocol family %u", af); 430 431 KASSERT(inph->inph_sp != NULL); 432 /* If we have a cached entry, and if it is still valid, use it. */ 433 IPSEC_STATINC(IPSEC_STAT_SPDCACHELOOKUP); 434 currsp = ipsec_checkpcbcache(m, inph->inph_sp, dir); 435 if (currsp) { 436 *error = 0; 437 return currsp; 438 } 439 IPSEC_STATINC(IPSEC_STAT_SPDCACHEMISS); 440 441 switch (af) { 442 case AF_INET: { 443 struct inpcb *in4p = (struct inpcb *)inph; 444 /* set spidx in pcb */ 445 *error = ipsec4_setspidx_inpcb(m, in4p); 446 pcbsp = in4p->inp_sp; 447 break; 448 } 449 #if defined(INET6) 450 case AF_INET6: { 451 struct in6pcb *in6p = (struct in6pcb *)inph; 452 /* set spidx in pcb */ 453 *error = ipsec6_setspidx_in6pcb(m, in6p); 454 pcbsp = in6p->in6p_sp; 455 break; 456 } 457 #endif 458 default: 459 *error = EPFNOSUPPORT; 460 break; 461 } 462 if (*error) 463 return NULL; 464 465 KASSERT(pcbsp != NULL); 466 switch (dir) { 467 case IPSEC_DIR_INBOUND: 468 currsp = pcbsp->sp_in; 469 break; 470 case IPSEC_DIR_OUTBOUND: 471 currsp = pcbsp->sp_out; 472 break; 473 } 474 KASSERT(currsp != NULL); 475 476 if (pcbsp->priv) { /* when privilieged socket */ 477 switch (currsp->policy) { 478 case IPSEC_POLICY_BYPASS: 479 case IPSEC_POLICY_IPSEC: 480 KEY_SP_REF(currsp); 481 sp = currsp; 482 break; 483 484 case IPSEC_POLICY_ENTRUST: 485 /* look for a policy in SPD */ 486 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 487 if (sp == NULL) /* no SP found */ 488 sp = KEY_GET_DEFAULT_SP(af); 489 break; 490 491 default: 492 IPSECLOG(LOG_ERR, "Invalid policy for PCB %d\n", 493 currsp->policy); 494 *error = EINVAL; 495 return NULL; 496 } 497 } else { /* unpriv, SPD has policy */ 498 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 499 if (sp == NULL) { /* no SP found */ 500 switch (currsp->policy) { 501 case IPSEC_POLICY_BYPASS: 502 IPSECLOG(LOG_ERR, "Illegal policy for " 503 "non-priviliged defined %d\n", 504 currsp->policy); 505 *error = EINVAL; 506 return NULL; 507 508 case IPSEC_POLICY_ENTRUST: 509 sp = KEY_GET_DEFAULT_SP(af); 510 break; 511 512 case IPSEC_POLICY_IPSEC: 513 KEY_SP_REF(currsp); 514 sp = currsp; 515 break; 516 517 default: 518 IPSECLOG(LOG_ERR, "Invalid policy for " 519 "PCB %d\n", currsp->policy); 520 *error = EINVAL; 521 return NULL; 522 } 523 } 524 } 525 KASSERTMSG(sp != NULL, "null SP (priv %u policy %u", pcbsp->priv, 526 currsp->policy); 527 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 528 "DP (priv %u policy %u) allocates SP:%p (refcnt %u)\n", 529 pcbsp->priv, currsp->policy, sp, key_sp_refcnt(sp)); 530 ipsec_fillpcbcache(pcbsp, m, sp, dir); 531 return sp; 532 } 533 534 /* 535 * For FORWARDING packet or OUTBOUND without a socket. Searching SPD for packet, 536 * and return a pointer to SP. 537 * OUT: positive: a pointer to the entry for security policy leaf matched. 538 * NULL: no apropreate SP found, the following value is set to error. 539 * 0 : bypass 540 * EACCES : discard packet. 541 * ENOENT : ipsec_acquire() in progress, maybe. 542 * others : error occurred. 543 */ 544 static struct secpolicy * 545 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 546 { 547 struct secpolicyindex spidx; 548 struct secpolicy *sp; 549 550 KASSERT(m != NULL); 551 KASSERT(error != NULL); 552 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 553 554 sp = NULL; 555 556 /* Make an index to look for a policy. */ 557 *error = ipsec_setspidx(m, &spidx, (flag & IP_FORWARDING) ? 0 : 1); 558 if (*error != 0) { 559 IPSECLOG(LOG_DEBUG, "setpidx failed, dir %u flag %u\n", dir, flag); 560 memset(&spidx, 0, sizeof(spidx)); 561 return NULL; 562 } 563 564 spidx.dir = dir; 565 566 if (key_havesp(dir)) { 567 sp = KEY_LOOKUP_SP_BYSPIDX(&spidx, dir); 568 } 569 570 if (sp == NULL) /* no SP found, use system default */ 571 sp = KEY_GET_DEFAULT_SP(spidx.dst.sa.sa_family); 572 KASSERT(sp != NULL); 573 return sp; 574 } 575 576 static struct secpolicy * 577 ipsec_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 578 void *inp) 579 { 580 struct secpolicy *sp; 581 582 *error = 0; 583 584 if (inp == NULL) { 585 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 586 } else { 587 struct inpcb_hdr *inph = (struct inpcb_hdr *)inp; 588 KASSERT(inph->inph_socket != NULL); 589 sp = ipsec_getpolicybysock(m, dir, inph, error); 590 } 591 if (sp == NULL) { 592 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 593 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 594 return NULL; 595 } 596 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 597 598 switch (sp->policy) { 599 case IPSEC_POLICY_ENTRUST: 600 default: 601 printf("%s: invalid policy %u\n", __func__, sp->policy); 602 /* fall thru... */ 603 case IPSEC_POLICY_DISCARD: 604 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 605 *error = -EINVAL; /* packet is discarded by caller */ 606 break; 607 case IPSEC_POLICY_BYPASS: 608 case IPSEC_POLICY_NONE: 609 KEY_SP_UNREF(&sp); 610 sp = NULL; /* NB: force NULL result */ 611 break; 612 case IPSEC_POLICY_IPSEC: 613 KASSERT(sp->req != NULL); 614 break; 615 } 616 617 if (*error != 0) { 618 KEY_SP_UNREF(&sp); 619 sp = NULL; 620 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 621 } 622 623 return sp; 624 } 625 626 int 627 ipsec4_output(struct mbuf *m, struct inpcb *inp, int flags, 628 u_long *mtu, bool *natt_frag, bool *done) 629 { 630 struct secpolicy *sp = NULL; 631 int error, s; 632 633 /* 634 * Check the security policy (SP) for the packet and, if required, 635 * do IPsec-related processing. There are two cases here; the first 636 * time a packet is sent through it will be untagged and handled by 637 * ipsec_checkpolicy(). If the packet is resubmitted to ip_output 638 * (e.g. after AH, ESP, etc. processing), there will be a tag to 639 * bypass the lookup and related policy checking. 640 */ 641 if (ipsec_outdone(m)) { 642 return 0; 643 } 644 s = splsoftnet(); 645 if (inp && ipsec_pcb_skip_ipsec(inp->inp_sp, IPSEC_DIR_OUTBOUND)) { 646 splx(s); 647 return 0; 648 } 649 sp = ipsec_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, inp); 650 651 /* 652 * There are four return cases: 653 * sp != NULL apply IPsec policy 654 * sp == NULL, error == 0 no IPsec handling needed 655 * sp == NULL, error == -EINVAL discard packet w/o error 656 * sp == NULL, error != 0 discard packet, report error 657 */ 658 if (sp == NULL) { 659 splx(s); 660 if (error) { 661 /* 662 * Hack: -EINVAL is used to signal that a packet 663 * should be silently discarded. This is typically 664 * because we asked key management for an SA and 665 * it was delayed (e.g. kicked up to IKE). 666 */ 667 if (error == -EINVAL) 668 error = 0; 669 m_freem(m); 670 *done = true; 671 return error; 672 } 673 /* No IPsec processing for this packet. */ 674 return 0; 675 } 676 677 /* 678 * Do delayed checksums now because we send before 679 * this is done in the normal processing path. 680 */ 681 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 682 in_delayed_cksum(m); 683 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 684 } 685 686 { 687 u_long _mtu = 0; 688 689 error = ipsec4_process_packet(m, sp->req, &_mtu); 690 691 if (error == 0 && _mtu != 0) { 692 /* 693 * NAT-T ESP fragmentation: do not do IPSec processing 694 * now, we will do it on each fragmented packet. 695 */ 696 *mtu = _mtu; 697 *natt_frag = true; 698 KEY_SP_UNREF(&sp); 699 splx(s); 700 return 0; 701 } 702 } 703 704 /* 705 * Preserve KAME behaviour: ENOENT can be returned 706 * when an SA acquire is in progress. Don't propagate 707 * this to user-level; it confuses applications. 708 * 709 * XXX this will go away when the SADB is redone. 710 */ 711 if (error == ENOENT) 712 error = 0; 713 KEY_SP_UNREF(&sp); 714 splx(s); 715 *done = true; 716 return error; 717 } 718 719 int 720 ipsec4_input(struct mbuf *m, int flags) 721 { 722 struct secpolicy *sp; 723 int error, s; 724 725 s = splsoftnet(); 726 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 727 if (sp == NULL) { 728 splx(s); 729 return EINVAL; 730 } 731 732 /* 733 * Check security policy against packet attributes. 734 */ 735 error = ipsec_sp_reject(sp, m); 736 KEY_SP_UNREF(&sp); 737 splx(s); 738 if (error) { 739 return error; 740 } 741 742 if (flags == 0) { 743 /* We are done. */ 744 return 0; 745 } 746 747 /* 748 * Peek at the outbound SP for this packet to determine if 749 * it is a Fast Forward candidate. 750 */ 751 s = splsoftnet(); 752 sp = ipsec_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, NULL); 753 if (sp != NULL) { 754 m->m_flags &= ~M_CANFASTFWD; 755 KEY_SP_UNREF(&sp); 756 } 757 splx(s); 758 return 0; 759 } 760 761 int 762 ipsec4_forward(struct mbuf *m, int *destmtu) 763 { 764 /* 765 * If the packet is routed over IPsec tunnel, tell the 766 * originator the tunnel MTU. 767 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 768 * XXX quickhack!!! 769 */ 770 struct secpolicy *sp; 771 size_t ipsechdr; 772 int error; 773 774 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, IP_FORWARDING, 775 &error); 776 if (sp == NULL) { 777 return EINVAL; 778 } 779 780 /* Count IPsec header size. */ 781 ipsechdr = ipsec_hdrsiz(m, IPSEC_DIR_OUTBOUND, NULL); 782 783 /* 784 * Find the correct route for outer IPv4 header, compute tunnel MTU. 785 */ 786 if (sp->req) { 787 struct secasvar *sav; 788 789 sav = ipsec_lookup_sa(sp->req, m); 790 if (sav != NULL) { 791 struct route *ro; 792 struct rtentry *rt; 793 794 ro = &sav->sah->sa_route; 795 rt = rtcache_validate(ro); 796 if (rt && rt->rt_ifp) { 797 *destmtu = rt->rt_rmx.rmx_mtu ? 798 rt->rt_rmx.rmx_mtu : rt->rt_ifp->if_mtu; 799 *destmtu -= ipsechdr; 800 } 801 rtcache_unref(rt, ro); 802 KEY_SA_UNREF(&sav); 803 } 804 } 805 KEY_SP_UNREF(&sp); 806 return 0; 807 } 808 809 static int 810 ipsec4_setspidx_inpcb(struct mbuf *m, struct inpcb *pcb) 811 { 812 int error; 813 814 KASSERT(pcb != NULL); 815 KASSERT(pcb->inp_sp != NULL); 816 KASSERT(pcb->inp_sp->sp_out != NULL); 817 KASSERT(pcb->inp_sp->sp_in != NULL); 818 819 error = ipsec_setspidx(m, &pcb->inp_sp->sp_in->spidx, 1); 820 if (error == 0) { 821 pcb->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 822 pcb->inp_sp->sp_out->spidx = pcb->inp_sp->sp_in->spidx; 823 pcb->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 824 } else { 825 memset(&pcb->inp_sp->sp_in->spidx, 0, 826 sizeof(pcb->inp_sp->sp_in->spidx)); 827 memset(&pcb->inp_sp->sp_out->spidx, 0, 828 sizeof(pcb->inp_sp->sp_in->spidx)); 829 } 830 return error; 831 } 832 833 #ifdef INET6 834 static int 835 ipsec6_setspidx_in6pcb(struct mbuf *m, struct in6pcb *pcb) 836 { 837 struct secpolicyindex *spidx; 838 int error; 839 840 KASSERT(pcb != NULL); 841 KASSERT(pcb->in6p_sp != NULL); 842 KASSERT(pcb->in6p_sp->sp_out != NULL); 843 KASSERT(pcb->in6p_sp->sp_in != NULL); 844 845 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 846 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 847 848 spidx = &pcb->in6p_sp->sp_in->spidx; 849 error = ipsec_setspidx(m, spidx, 1); 850 if (error) 851 goto bad; 852 spidx->dir = IPSEC_DIR_INBOUND; 853 854 spidx = &pcb->in6p_sp->sp_out->spidx; 855 error = ipsec_setspidx(m, spidx, 1); 856 if (error) 857 goto bad; 858 spidx->dir = IPSEC_DIR_OUTBOUND; 859 860 return 0; 861 862 bad: 863 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 864 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 865 return error; 866 } 867 #endif 868 869 /* 870 * configure security policy index (src/dst/proto/sport/dport) 871 * by looking at the content of mbuf. 872 * the caller is responsible for error recovery (like clearing up spidx). 873 */ 874 static int 875 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 876 { 877 struct ip *ip = NULL; 878 struct ip ipbuf; 879 u_int v; 880 struct mbuf *n; 881 int len; 882 int error; 883 884 KASSERT(m != NULL); 885 886 /* 887 * validate m->m_pkthdr.len. we see incorrect length if we 888 * mistakenly call this function with inconsistent mbuf chain 889 * (like 4.4BSD tcp/udp processing). XXX should we panic here? 890 */ 891 len = 0; 892 for (n = m; n; n = n->m_next) 893 len += n->m_len; 894 if (m->m_pkthdr.len != len) { 895 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 896 "total of m_len(%d) != pkthdr.len(%d), ignored.\n", 897 len, m->m_pkthdr.len); 898 KASSERTMSG(0, "impossible"); 899 return EINVAL; 900 } 901 902 if (m->m_pkthdr.len < sizeof(struct ip)) { 903 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 904 "pkthdr.len(%d) < sizeof(struct ip), ignored.\n", 905 m->m_pkthdr.len); 906 return EINVAL; 907 } 908 909 if (m->m_len >= sizeof(*ip)) { 910 ip = mtod(m, struct ip *); 911 } else { 912 m_copydata(m, 0, sizeof(ipbuf), &ipbuf); 913 ip = &ipbuf; 914 } 915 v = ip->ip_v; 916 switch (v) { 917 case 4: 918 error = ipsec4_setspidx_ipaddr(m, spidx); 919 if (error) 920 return error; 921 ipsec4_get_ulp(m, spidx, needport); 922 return 0; 923 #ifdef INET6 924 case 6: 925 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 926 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 927 "pkthdr.len(%d) < sizeof(struct ip6_hdr), " 928 "ignored.\n", m->m_pkthdr.len); 929 return EINVAL; 930 } 931 error = ipsec6_setspidx_ipaddr(m, spidx); 932 if (error) 933 return error; 934 ipsec6_get_ulp(m, spidx, needport); 935 return 0; 936 #endif 937 default: 938 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 939 "unknown IP version %u, ignored.\n", v); 940 return EINVAL; 941 } 942 } 943 944 static void 945 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 946 { 947 u_int8_t nxt; 948 int off; 949 950 KASSERT(m != NULL); 951 KASSERTMSG(m->m_pkthdr.len >= sizeof(struct ip), "packet too short"); 952 953 /* NB: ip_input() flips it into host endian XXX need more checking */ 954 if (m->m_len >= sizeof(struct ip)) { 955 struct ip *ip = mtod(m, struct ip *); 956 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 957 goto done; 958 off = ip->ip_hl << 2; 959 nxt = ip->ip_p; 960 } else { 961 struct ip ih; 962 963 m_copydata(m, 0, sizeof(struct ip), &ih); 964 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 965 goto done; 966 off = ih.ip_hl << 2; 967 nxt = ih.ip_p; 968 } 969 970 while (off < m->m_pkthdr.len) { 971 struct ip6_ext ip6e; 972 struct tcphdr th; 973 struct udphdr uh; 974 struct icmp icmph; 975 976 switch (nxt) { 977 case IPPROTO_TCP: 978 spidx->ul_proto = nxt; 979 if (!needport) 980 goto done_proto; 981 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 982 goto done; 983 m_copydata(m, off, sizeof(th), &th); 984 spidx->src.sin.sin_port = th.th_sport; 985 spidx->dst.sin.sin_port = th.th_dport; 986 return; 987 case IPPROTO_UDP: 988 spidx->ul_proto = nxt; 989 if (!needport) 990 goto done_proto; 991 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 992 goto done; 993 m_copydata(m, off, sizeof(uh), &uh); 994 spidx->src.sin.sin_port = uh.uh_sport; 995 spidx->dst.sin.sin_port = uh.uh_dport; 996 return; 997 case IPPROTO_AH: 998 if (off + sizeof(ip6e) > m->m_pkthdr.len) 999 goto done; 1000 /* XXX sigh, this works but is totally bogus */ 1001 m_copydata(m, off, sizeof(ip6e), &ip6e); 1002 off += (ip6e.ip6e_len + 2) << 2; 1003 nxt = ip6e.ip6e_nxt; 1004 break; 1005 case IPPROTO_ICMP: 1006 spidx->ul_proto = nxt; 1007 if (off + sizeof(struct icmp) > m->m_pkthdr.len) 1008 goto done; 1009 m_copydata(m, off, sizeof(icmph), &icmph); 1010 ((struct sockaddr_in *)&spidx->src)->sin_port = 1011 htons((uint16_t)icmph.icmp_type); 1012 ((struct sockaddr_in *)&spidx->dst)->sin_port = 1013 htons((uint16_t)icmph.icmp_code); 1014 return; 1015 default: 1016 /* XXX intermediate headers??? */ 1017 spidx->ul_proto = nxt; 1018 goto done_proto; 1019 } 1020 } 1021 done: 1022 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1023 done_proto: 1024 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 1025 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 1026 } 1027 1028 static int 1029 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1030 { 1031 static const struct sockaddr_in template = { 1032 sizeof(struct sockaddr_in), 1033 AF_INET, 1034 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 1035 }; 1036 1037 spidx->src.sin = template; 1038 spidx->dst.sin = template; 1039 1040 if (m->m_len < sizeof(struct ip)) { 1041 m_copydata(m, offsetof(struct ip, ip_src), 1042 sizeof(struct in_addr), &spidx->src.sin.sin_addr); 1043 m_copydata(m, offsetof(struct ip, ip_dst), 1044 sizeof(struct in_addr), &spidx->dst.sin.sin_addr); 1045 } else { 1046 struct ip *ip = mtod(m, struct ip *); 1047 spidx->src.sin.sin_addr = ip->ip_src; 1048 spidx->dst.sin.sin_addr = ip->ip_dst; 1049 } 1050 1051 spidx->prefs = sizeof(struct in_addr) << 3; 1052 spidx->prefd = sizeof(struct in_addr) << 3; 1053 1054 return 0; 1055 } 1056 1057 #ifdef INET6 1058 static void 1059 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 1060 { 1061 int off, nxt; 1062 struct tcphdr th; 1063 struct udphdr uh; 1064 struct icmp6_hdr icmph; 1065 1066 KASSERT(m != NULL); 1067 1068 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1069 kdebug_mbuf(__func__, m); 1070 } 1071 1072 /* set default */ 1073 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1074 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 1075 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 1076 1077 nxt = -1; 1078 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 1079 if (off < 0 || m->m_pkthdr.len < off) 1080 return; 1081 1082 switch (nxt) { 1083 case IPPROTO_TCP: 1084 spidx->ul_proto = nxt; 1085 if (!needport) 1086 break; 1087 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1088 break; 1089 m_copydata(m, off, sizeof(th), &th); 1090 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 1091 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 1092 break; 1093 case IPPROTO_UDP: 1094 spidx->ul_proto = nxt; 1095 if (!needport) 1096 break; 1097 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1098 break; 1099 m_copydata(m, off, sizeof(uh), &uh); 1100 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 1101 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 1102 break; 1103 case IPPROTO_ICMPV6: 1104 spidx->ul_proto = nxt; 1105 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 1106 break; 1107 m_copydata(m, off, sizeof(icmph), &icmph); 1108 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 1109 htons((uint16_t)icmph.icmp6_type); 1110 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 1111 htons((uint16_t)icmph.icmp6_code); 1112 break; 1113 default: 1114 /* XXX intermediate headers??? */ 1115 spidx->ul_proto = nxt; 1116 break; 1117 } 1118 } 1119 1120 static int 1121 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1122 { 1123 struct ip6_hdr *ip6 = NULL; 1124 struct ip6_hdr ip6buf; 1125 struct sockaddr_in6 *sin6; 1126 1127 if (m->m_len >= sizeof(*ip6)) 1128 ip6 = mtod(m, struct ip6_hdr *); 1129 else { 1130 m_copydata(m, 0, sizeof(ip6buf), &ip6buf); 1131 ip6 = &ip6buf; 1132 } 1133 1134 sin6 = (struct sockaddr_in6 *)&spidx->src; 1135 memset(sin6, 0, sizeof(*sin6)); 1136 sin6->sin6_family = AF_INET6; 1137 sin6->sin6_len = sizeof(struct sockaddr_in6); 1138 memcpy(&sin6->sin6_addr, &ip6->ip6_src, sizeof(ip6->ip6_src)); 1139 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 1140 sin6->sin6_addr.s6_addr16[1] = 0; 1141 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 1142 } 1143 spidx->prefs = sizeof(struct in6_addr) << 3; 1144 1145 sin6 = (struct sockaddr_in6 *)&spidx->dst; 1146 memset(sin6, 0, sizeof(*sin6)); 1147 sin6->sin6_family = AF_INET6; 1148 sin6->sin6_len = sizeof(struct sockaddr_in6); 1149 memcpy(&sin6->sin6_addr, &ip6->ip6_dst, sizeof(ip6->ip6_dst)); 1150 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 1151 sin6->sin6_addr.s6_addr16[1] = 0; 1152 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 1153 } 1154 spidx->prefd = sizeof(struct in6_addr) << 3; 1155 1156 return 0; 1157 } 1158 #endif 1159 1160 static void 1161 ipsec_delpcbpolicy(struct inpcbpolicy *p) 1162 { 1163 1164 kmem_intr_free(p, sizeof(*p)); 1165 } 1166 1167 /* initialize policy in PCB */ 1168 int 1169 ipsec_init_policy(struct socket *so, struct inpcbpolicy **policy) 1170 { 1171 struct inpcbpolicy *new; 1172 1173 KASSERT(so != NULL); 1174 KASSERT(policy != NULL); 1175 1176 new = kmem_intr_zalloc(sizeof(*new), KM_NOSLEEP); 1177 if (new == NULL) { 1178 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1179 return ENOBUFS; 1180 } 1181 1182 if (IPSEC_PRIVILEGED_SO(so)) 1183 new->priv = 1; 1184 else 1185 new->priv = 0; 1186 1187 /* 1188 * Set dummy SPs. Actual SPs will be allocated later if needed. 1189 */ 1190 new->sp_in = &ipsec_dummy_sp; 1191 new->sp_out = &ipsec_dummy_sp; 1192 1193 *policy = new; 1194 1195 return 0; 1196 } 1197 1198 #if 0 /* unused */ 1199 /* copy old ipsec policy into new */ 1200 int 1201 ipsec_copy_policy(const struct inpcbpolicy *old, struct inpcbpolicy *new) 1202 { 1203 struct secpolicy *sp; 1204 1205 sp = ipsec_deepcopy_policy(old->sp_in); 1206 if (sp) { 1207 KEY_SP_UNREF(&new->sp_in); 1208 new->sp_in = sp; 1209 } else 1210 return ENOBUFS; 1211 1212 sp = ipsec_deepcopy_policy(old->sp_out); 1213 if (sp) { 1214 KEY_SP_UNREF(&new->sp_out); 1215 new->sp_out = sp; 1216 } else 1217 return ENOBUFS; 1218 1219 new->priv = old->priv; 1220 1221 return 0; 1222 } 1223 1224 /* deep-copy a policy in PCB */ 1225 static struct secpolicy * 1226 ipsec_deepcopy_policy(const struct secpolicy *src) 1227 { 1228 struct ipsecrequest *newchain = NULL; 1229 const struct ipsecrequest *p; 1230 struct ipsecrequest **q; 1231 struct secpolicy *dst; 1232 1233 if (src == NULL) 1234 return NULL; 1235 dst = KEY_NEWSP(); 1236 if (dst == NULL) 1237 return NULL; 1238 1239 /* 1240 * deep-copy IPsec request chain. This is required since struct 1241 * ipsecrequest is not reference counted. 1242 */ 1243 q = &newchain; 1244 for (p = src->req; p; p = p->next) { 1245 *q = kmem_zalloc(sizeof(**q), KM_SLEEP); 1246 (*q)->next = NULL; 1247 1248 (*q)->saidx.proto = p->saidx.proto; 1249 (*q)->saidx.mode = p->saidx.mode; 1250 (*q)->level = p->level; 1251 (*q)->saidx.reqid = p->saidx.reqid; 1252 1253 memcpy(&(*q)->saidx.src, &p->saidx.src, sizeof((*q)->saidx.src)); 1254 memcpy(&(*q)->saidx.dst, &p->saidx.dst, sizeof((*q)->saidx.dst)); 1255 1256 (*q)->sp = dst; 1257 1258 q = &((*q)->next); 1259 } 1260 1261 dst->req = newchain; 1262 dst->state = src->state; 1263 dst->policy = src->policy; 1264 /* do not touch the refcnt fields */ 1265 1266 return dst; 1267 } 1268 #endif 1269 1270 static void 1271 ipsec_destroy_policy(struct secpolicy *sp) 1272 { 1273 1274 if (sp == &ipsec_dummy_sp) 1275 ; /* It's dummy. No need to free it. */ 1276 else { 1277 /* 1278 * We cannot destroy here because it can be called in 1279 * softint. So mark the SP as DEAD and let the timer 1280 * destroy it. See key_timehandler_spd. 1281 */ 1282 sp->state = IPSEC_SPSTATE_DEAD; 1283 } 1284 } 1285 1286 /* set policy and ipsec request if present. */ 1287 static int 1288 ipsec_set_policy(struct secpolicy **policy, int optname, const void *request, 1289 size_t len, kauth_cred_t cred) 1290 { 1291 const struct sadb_x_policy *xpl; 1292 struct secpolicy *newsp = NULL, *oldsp; 1293 int error; 1294 1295 KASSERT(!cpu_softintr_p()); 1296 1297 /* sanity check. */ 1298 if (policy == NULL || *policy == NULL || request == NULL) 1299 return EINVAL; 1300 if (len < sizeof(*xpl)) 1301 return EINVAL; 1302 xpl = (const struct sadb_x_policy *)request; 1303 1304 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1305 kdebug_sadb_xpolicy("set passed policy", request); 1306 } 1307 1308 /* check policy type */ 1309 /* ipsec_set_policy() accepts IPSEC, ENTRUST and BYPASS. */ 1310 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD || 1311 xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1312 return EINVAL; 1313 1314 /* check privileged socket */ 1315 if (xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1316 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPSEC, 1317 KAUTH_REQ_NETWORK_IPSEC_BYPASS, NULL, NULL, NULL); 1318 if (error) 1319 return error; 1320 } 1321 1322 /* allocation new SP entry */ 1323 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1324 return error; 1325 1326 key_init_sp(newsp); 1327 newsp->created = time_uptime; 1328 /* Insert the global list for SPs for sockets */ 1329 key_socksplist_add(newsp); 1330 1331 /* clear old SP and set new SP */ 1332 oldsp = *policy; 1333 *policy = newsp; 1334 ipsec_destroy_policy(oldsp); 1335 1336 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1337 printf("%s: new policy\n", __func__); 1338 kdebug_secpolicy(newsp); 1339 } 1340 1341 return 0; 1342 } 1343 1344 static int 1345 ipsec_get_policy(struct secpolicy *policy, struct mbuf **mp) 1346 { 1347 1348 /* sanity check. */ 1349 if (policy == NULL || mp == NULL) 1350 return EINVAL; 1351 1352 *mp = key_sp2msg(policy, M_NOWAIT); 1353 if (!*mp) { 1354 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1355 return ENOBUFS; 1356 } 1357 1358 (*mp)->m_type = MT_DATA; 1359 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1360 kdebug_mbuf(__func__, *mp); 1361 } 1362 1363 return 0; 1364 } 1365 1366 int 1367 ipsec4_set_policy(struct inpcb *inp, int optname, const void *request, 1368 size_t len, kauth_cred_t cred) 1369 { 1370 const struct sadb_x_policy *xpl; 1371 struct secpolicy **policy; 1372 1373 KASSERT(!cpu_softintr_p()); 1374 KASSERT(inp != NULL); 1375 KASSERT(inp_locked(inp)); 1376 KASSERT(request != NULL); 1377 1378 if (len < sizeof(*xpl)) 1379 return EINVAL; 1380 xpl = (const struct sadb_x_policy *)request; 1381 1382 KASSERT(inp->inp_sp != NULL); 1383 1384 /* select direction */ 1385 switch (xpl->sadb_x_policy_dir) { 1386 case IPSEC_DIR_INBOUND: 1387 policy = &inp->inp_sp->sp_in; 1388 break; 1389 case IPSEC_DIR_OUTBOUND: 1390 policy = &inp->inp_sp->sp_out; 1391 break; 1392 default: 1393 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1394 xpl->sadb_x_policy_dir); 1395 return EINVAL; 1396 } 1397 1398 return ipsec_set_policy(policy, optname, request, len, cred); 1399 } 1400 1401 int 1402 ipsec4_get_policy(struct inpcb *inp, const void *request, size_t len, 1403 struct mbuf **mp) 1404 { 1405 const struct sadb_x_policy *xpl; 1406 struct secpolicy *policy; 1407 1408 /* sanity check. */ 1409 if (inp == NULL || request == NULL || mp == NULL) 1410 return EINVAL; 1411 KASSERT(inp->inp_sp != NULL); 1412 if (len < sizeof(*xpl)) 1413 return EINVAL; 1414 xpl = (const struct sadb_x_policy *)request; 1415 1416 /* select direction */ 1417 switch (xpl->sadb_x_policy_dir) { 1418 case IPSEC_DIR_INBOUND: 1419 policy = inp->inp_sp->sp_in; 1420 break; 1421 case IPSEC_DIR_OUTBOUND: 1422 policy = inp->inp_sp->sp_out; 1423 break; 1424 default: 1425 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1426 xpl->sadb_x_policy_dir); 1427 return EINVAL; 1428 } 1429 1430 return ipsec_get_policy(policy, mp); 1431 } 1432 1433 int 1434 ipsec4_delete_pcbpolicy(struct inpcb *inp) 1435 { 1436 1437 KASSERT(inp != NULL); 1438 1439 if (inp->inp_sp == NULL) 1440 return 0; 1441 1442 if (inp->inp_sp->sp_in != NULL) 1443 ipsec_destroy_policy(inp->inp_sp->sp_in); 1444 1445 if (inp->inp_sp->sp_out != NULL) 1446 ipsec_destroy_policy(inp->inp_sp->sp_out); 1447 1448 ipsec_invalpcbcache(inp->inp_sp, IPSEC_DIR_ANY); 1449 1450 ipsec_delpcbpolicy(inp->inp_sp); 1451 inp->inp_sp = NULL; 1452 1453 return 0; 1454 } 1455 1456 #ifdef INET6 1457 int 1458 ipsec6_set_policy(struct in6pcb *in6p, int optname, const void *request, 1459 size_t len, kauth_cred_t cred) 1460 { 1461 const struct sadb_x_policy *xpl; 1462 struct secpolicy **policy; 1463 1464 KASSERT(!cpu_softintr_p()); 1465 KASSERT(in6p != NULL); 1466 KASSERT(in6p_locked(in6p)); 1467 KASSERT(request != NULL); 1468 1469 if (len < sizeof(*xpl)) 1470 return EINVAL; 1471 xpl = (const struct sadb_x_policy *)request; 1472 1473 /* select direction */ 1474 switch (xpl->sadb_x_policy_dir) { 1475 case IPSEC_DIR_INBOUND: 1476 policy = &in6p->in6p_sp->sp_in; 1477 break; 1478 case IPSEC_DIR_OUTBOUND: 1479 policy = &in6p->in6p_sp->sp_out; 1480 break; 1481 default: 1482 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1483 xpl->sadb_x_policy_dir); 1484 return EINVAL; 1485 } 1486 1487 return ipsec_set_policy(policy, optname, request, len, cred); 1488 } 1489 1490 int 1491 ipsec6_get_policy(struct in6pcb *in6p, const void *request, size_t len, 1492 struct mbuf **mp) 1493 { 1494 const struct sadb_x_policy *xpl; 1495 struct secpolicy *policy; 1496 1497 /* sanity check. */ 1498 if (in6p == NULL || request == NULL || mp == NULL) 1499 return EINVAL; 1500 KASSERT(in6p->in6p_sp != NULL); 1501 if (len < sizeof(*xpl)) 1502 return EINVAL; 1503 xpl = (const struct sadb_x_policy *)request; 1504 1505 /* select direction */ 1506 switch (xpl->sadb_x_policy_dir) { 1507 case IPSEC_DIR_INBOUND: 1508 policy = in6p->in6p_sp->sp_in; 1509 break; 1510 case IPSEC_DIR_OUTBOUND: 1511 policy = in6p->in6p_sp->sp_out; 1512 break; 1513 default: 1514 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1515 xpl->sadb_x_policy_dir); 1516 return EINVAL; 1517 } 1518 1519 return ipsec_get_policy(policy, mp); 1520 } 1521 1522 int 1523 ipsec6_delete_pcbpolicy(struct in6pcb *in6p) 1524 { 1525 1526 KASSERT(in6p != NULL); 1527 1528 if (in6p->in6p_sp == NULL) 1529 return 0; 1530 1531 if (in6p->in6p_sp->sp_in != NULL) 1532 ipsec_destroy_policy(in6p->in6p_sp->sp_in); 1533 1534 if (in6p->in6p_sp->sp_out != NULL) 1535 ipsec_destroy_policy(in6p->in6p_sp->sp_out); 1536 1537 ipsec_invalpcbcache(in6p->in6p_sp, IPSEC_DIR_ANY); 1538 1539 ipsec_delpcbpolicy(in6p->in6p_sp); 1540 in6p->in6p_sp = NULL; 1541 1542 return 0; 1543 } 1544 #endif 1545 1546 /* 1547 * Return the current level (either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE). 1548 */ 1549 u_int 1550 ipsec_get_reqlevel(const struct ipsecrequest *isr) 1551 { 1552 u_int level = 0; 1553 u_int esp_trans_deflev, esp_net_deflev; 1554 u_int ah_trans_deflev, ah_net_deflev; 1555 1556 KASSERT(isr != NULL); 1557 KASSERT(isr->sp != NULL); 1558 KASSERTMSG( 1559 isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1560 "af family mismatch, src %u, dst %u", 1561 isr->sp->spidx.src.sa.sa_family, isr->sp->spidx.dst.sa.sa_family); 1562 1563 /* XXX note that we have ipseclog() expanded here - code sync issue */ 1564 #define IPSEC_CHECK_DEFAULT(lev) \ 1565 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1566 && (lev) != IPSEC_LEVEL_UNIQUE) ? \ 1567 (ipsec_debug ? log(LOG_INFO, "fixed system default level " #lev \ 1568 ":%d->%d\n", (lev), IPSEC_LEVEL_REQUIRE) : (void)0), \ 1569 (lev) = IPSEC_LEVEL_REQUIRE, (lev) \ 1570 : (lev)) 1571 1572 /* set default level */ 1573 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1574 #ifdef INET 1575 case AF_INET: 1576 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_trans_deflev); 1577 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_net_deflev); 1578 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_trans_deflev); 1579 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_net_deflev); 1580 break; 1581 #endif 1582 #ifdef INET6 1583 case AF_INET6: 1584 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_trans_deflev); 1585 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_net_deflev); 1586 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_trans_deflev); 1587 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_net_deflev); 1588 break; 1589 #endif /* INET6 */ 1590 default: 1591 panic("%s: unknown af %u", __func__, 1592 isr->sp->spidx.src.sa.sa_family); 1593 } 1594 1595 #undef IPSEC_CHECK_DEFAULT 1596 1597 /* set level */ 1598 switch (isr->level) { 1599 case IPSEC_LEVEL_DEFAULT: 1600 switch (isr->saidx.proto) { 1601 case IPPROTO_ESP: 1602 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1603 level = esp_net_deflev; 1604 else 1605 level = esp_trans_deflev; 1606 break; 1607 case IPPROTO_AH: 1608 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1609 level = ah_net_deflev; 1610 else 1611 level = ah_trans_deflev; 1612 break; 1613 case IPPROTO_IPCOMP: 1614 /* 1615 * we don't really care, as IPcomp document says that 1616 * we shouldn't compress small packets 1617 */ 1618 level = IPSEC_LEVEL_USE; 1619 break; 1620 default: 1621 panic("%s: Illegal protocol defined %u", __func__, 1622 isr->saidx.proto); 1623 } 1624 break; 1625 1626 case IPSEC_LEVEL_USE: 1627 case IPSEC_LEVEL_REQUIRE: 1628 level = isr->level; 1629 break; 1630 case IPSEC_LEVEL_UNIQUE: 1631 level = IPSEC_LEVEL_REQUIRE; 1632 break; 1633 1634 default: 1635 panic("%s: Illegal IPsec level %u", __func__, isr->level); 1636 } 1637 1638 return level; 1639 } 1640 1641 /* 1642 * Check security policy requirements against the actual packet contents. 1643 * 1644 * If the SP requires an IPsec packet, and the packet was neither AH nor ESP, 1645 * then kick it. 1646 */ 1647 int 1648 ipsec_sp_reject(const struct secpolicy *sp, const struct mbuf *m) 1649 { 1650 struct ipsecrequest *isr; 1651 1652 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1653 printf("%s: using SP\n", __func__); 1654 kdebug_secpolicy(sp); 1655 } 1656 1657 /* check policy */ 1658 switch (sp->policy) { 1659 case IPSEC_POLICY_DISCARD: 1660 return 1; 1661 case IPSEC_POLICY_BYPASS: 1662 case IPSEC_POLICY_NONE: 1663 return 0; 1664 } 1665 1666 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1667 "invalid policy %u", sp->policy); 1668 1669 /* XXX should compare policy against ipsec header history */ 1670 1671 for (isr = sp->req; isr != NULL; isr = isr->next) { 1672 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1673 continue; 1674 switch (isr->saidx.proto) { 1675 case IPPROTO_ESP: 1676 if ((m->m_flags & M_DECRYPTED) == 0) { 1677 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1678 "ESP m_flags:%x\n", m->m_flags); 1679 return 1; 1680 } 1681 break; 1682 case IPPROTO_AH: 1683 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1684 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1685 "AH m_flags:%x\n", m->m_flags); 1686 return 1; 1687 } 1688 break; 1689 case IPPROTO_IPCOMP: 1690 /* 1691 * We don't really care, as IPcomp document 1692 * says that we shouldn't compress small 1693 * packets, IPComp policy should always be 1694 * treated as being in "use" level. 1695 */ 1696 break; 1697 } 1698 } 1699 1700 return 0; 1701 } 1702 1703 /* 1704 * Check AH/ESP integrity. 1705 * This function is called from tcp_input(), udp_input(), 1706 * and {ah,esp}4_input for tunnel mode 1707 */ 1708 int 1709 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1710 { 1711 struct inpcb_hdr *inph = (struct inpcb_hdr *)inp; 1712 struct secpolicy *sp; 1713 int error; 1714 int result; 1715 1716 KASSERT(m != NULL); 1717 1718 if (inph == NULL) 1719 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 1720 IP_FORWARDING, &error); 1721 else 1722 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1723 inph, &error); 1724 1725 if (sp != NULL) { 1726 result = ipsec_sp_reject(sp, m); 1727 if (result) 1728 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1729 KEY_SP_UNREF(&sp); 1730 } else { 1731 result = 0; 1732 } 1733 return result; 1734 } 1735 1736 #ifdef INET6 1737 /* 1738 * Check AH/ESP integrity. 1739 * This function is called from tcp6_input(), udp6_input(), 1740 * and {ah,esp}6_input for tunnel mode 1741 */ 1742 int 1743 ipsec6_in_reject(struct mbuf *m, struct in6pcb *in6p) 1744 { 1745 struct inpcb_hdr *inph = (struct inpcb_hdr *)in6p; 1746 struct secpolicy *sp; 1747 int error; 1748 int result; 1749 1750 KASSERT(m != NULL); 1751 1752 if (inph == NULL) 1753 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 1754 IP_FORWARDING, &error); 1755 else 1756 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1757 inph, &error); 1758 1759 if (sp != NULL) { 1760 result = ipsec_sp_reject(sp, m); 1761 if (result) 1762 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1763 KEY_SP_UNREF(&sp); 1764 } else { 1765 result = 0; 1766 } 1767 return result; 1768 } 1769 #endif 1770 1771 /* 1772 * Compute the byte size to be occupied by the IPsec header. If it is 1773 * tunneled, it includes the size of outer IP header. 1774 */ 1775 static size_t 1776 ipsec_sp_hdrsiz(const struct secpolicy *sp, const struct mbuf *m) 1777 { 1778 struct ipsecrequest *isr; 1779 size_t siz; 1780 1781 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1782 printf("%s: using SP\n", __func__); 1783 kdebug_secpolicy(sp); 1784 } 1785 1786 switch (sp->policy) { 1787 case IPSEC_POLICY_DISCARD: 1788 case IPSEC_POLICY_BYPASS: 1789 case IPSEC_POLICY_NONE: 1790 return 0; 1791 } 1792 1793 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1794 "invalid policy %u", sp->policy); 1795 1796 siz = 0; 1797 for (isr = sp->req; isr != NULL; isr = isr->next) { 1798 size_t clen = 0; 1799 struct secasvar *sav; 1800 1801 switch (isr->saidx.proto) { 1802 case IPPROTO_ESP: 1803 sav = ipsec_lookup_sa(isr, m); 1804 if (sav != NULL) { 1805 clen = esp_hdrsiz(sav); 1806 KEY_SA_UNREF(&sav); 1807 } else 1808 clen = esp_hdrsiz(NULL); 1809 break; 1810 case IPPROTO_AH: 1811 sav = ipsec_lookup_sa(isr, m); 1812 if (sav != NULL) { 1813 clen = ah_hdrsiz(sav); 1814 KEY_SA_UNREF(&sav); 1815 } else 1816 clen = ah_hdrsiz(NULL); 1817 break; 1818 case IPPROTO_IPCOMP: 1819 clen = sizeof(struct ipcomp); 1820 break; 1821 } 1822 1823 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1824 switch (isr->saidx.dst.sa.sa_family) { 1825 case AF_INET: 1826 clen += sizeof(struct ip); 1827 break; 1828 #ifdef INET6 1829 case AF_INET6: 1830 clen += sizeof(struct ip6_hdr); 1831 break; 1832 #endif 1833 default: 1834 IPSECLOG(LOG_ERR, "unknown AF %d in " 1835 "IPsec tunnel SA\n", 1836 ((const struct sockaddr *)&isr->saidx.dst) 1837 ->sa_family); 1838 break; 1839 } 1840 } 1841 siz += clen; 1842 } 1843 1844 return siz; 1845 } 1846 1847 size_t 1848 ipsec_hdrsiz(struct mbuf *m, u_int dir, void *inp) 1849 { 1850 struct inpcb_hdr *inph = (struct inpcb_hdr *)inp; 1851 struct secpolicy *sp; 1852 int error; 1853 size_t size; 1854 1855 KASSERT(m != NULL); 1856 KASSERTMSG(inph == NULL || inph->inph_socket != NULL, 1857 "socket w/o inpcb"); 1858 1859 if (inph == NULL) 1860 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1861 else 1862 sp = ipsec_getpolicybysock(m, dir, inph, &error); 1863 1864 if (sp != NULL) { 1865 size = ipsec_sp_hdrsiz(sp, m); 1866 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%zu.\n", size); 1867 KEY_SP_UNREF(&sp); 1868 } else { 1869 size = 0; 1870 } 1871 1872 return size; 1873 } 1874 1875 /* 1876 * Check the variable replay window. 1877 * ipsec_chkreplay() performs replay check before ICV verification. 1878 * ipsec_updatereplay() updates replay bitmap. This must be called after 1879 * ICV verification (it also performs replay check, which is usually done 1880 * beforehand). 1881 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1882 * 1883 * based on RFC 2401. 1884 */ 1885 int 1886 ipsec_chkreplay(u_int32_t seq, const struct secasvar *sav) 1887 { 1888 const struct secreplay *replay; 1889 u_int32_t diff; 1890 int fr; 1891 u_int32_t wsizeb; /* constant: bits of window size */ 1892 int frlast; /* constant: last frame */ 1893 1894 IPSEC_SPLASSERT_SOFTNET(__func__); 1895 1896 KASSERT(sav != NULL); 1897 KASSERT(sav->replay != NULL); 1898 1899 replay = sav->replay; 1900 1901 if (replay->wsize == 0) 1902 return 1; /* no need to check replay. */ 1903 1904 /* constant */ 1905 frlast = replay->wsize - 1; 1906 wsizeb = replay->wsize << 3; 1907 1908 /* sequence number of 0 is invalid */ 1909 if (seq == 0) 1910 return 0; 1911 1912 /* first time is always okay */ 1913 if (replay->count == 0) 1914 return 1; 1915 1916 if (seq > replay->lastseq) { 1917 /* larger sequences are okay */ 1918 return 1; 1919 } else { 1920 /* seq is equal or less than lastseq. */ 1921 diff = replay->lastseq - seq; 1922 1923 /* over range to check, i.e. too old or wrapped */ 1924 if (diff >= wsizeb) 1925 return 0; 1926 1927 fr = frlast - diff / 8; 1928 1929 /* this packet already seen ? */ 1930 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1931 return 0; 1932 1933 /* out of order but good */ 1934 return 1; 1935 } 1936 } 1937 1938 /* 1939 * check replay counter whether to update or not. 1940 * OUT: 0: OK 1941 * 1: NG 1942 */ 1943 int 1944 ipsec_updatereplay(u_int32_t seq, const struct secasvar *sav) 1945 { 1946 struct secreplay *replay; 1947 u_int32_t diff; 1948 int fr; 1949 u_int32_t wsizeb; /* constant: bits of window size */ 1950 int frlast; /* constant: last frame */ 1951 1952 IPSEC_SPLASSERT_SOFTNET(__func__); 1953 1954 KASSERT(sav != NULL); 1955 KASSERT(sav->replay != NULL); 1956 1957 replay = sav->replay; 1958 1959 if (replay->wsize == 0) 1960 goto ok; /* no need to check replay. */ 1961 1962 /* constant */ 1963 frlast = replay->wsize - 1; 1964 wsizeb = replay->wsize << 3; 1965 1966 /* sequence number of 0 is invalid */ 1967 if (seq == 0) 1968 return 1; 1969 1970 /* first time */ 1971 if (replay->count == 0) { 1972 replay->lastseq = seq; 1973 memset(replay->bitmap, 0, replay->wsize); 1974 (replay->bitmap)[frlast] = 1; 1975 goto ok; 1976 } 1977 1978 if (seq > replay->lastseq) { 1979 /* seq is larger than lastseq. */ 1980 diff = seq - replay->lastseq; 1981 1982 /* new larger sequence number */ 1983 if (diff < wsizeb) { 1984 /* In window */ 1985 /* set bit for this packet */ 1986 vshiftl(replay->bitmap, diff, replay->wsize); 1987 (replay->bitmap)[frlast] |= 1; 1988 } else { 1989 /* this packet has a "way larger" */ 1990 memset(replay->bitmap, 0, replay->wsize); 1991 (replay->bitmap)[frlast] = 1; 1992 } 1993 replay->lastseq = seq; 1994 1995 /* larger is good */ 1996 } else { 1997 /* seq is equal or less than lastseq. */ 1998 diff = replay->lastseq - seq; 1999 2000 /* over range to check, i.e. too old or wrapped */ 2001 if (diff >= wsizeb) 2002 return 1; 2003 2004 fr = frlast - diff / 8; 2005 2006 /* this packet already seen ? */ 2007 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2008 return 1; 2009 2010 /* mark as seen */ 2011 (replay->bitmap)[fr] |= (1 << (diff % 8)); 2012 2013 /* out of order but good */ 2014 } 2015 2016 ok: 2017 if (replay->count == ~0) { 2018 char buf[IPSEC_LOGSASTRLEN]; 2019 2020 /* set overflow flag */ 2021 replay->overflow++; 2022 2023 /* don't increment, no more packets accepted */ 2024 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 2025 return 1; 2026 2027 IPSECLOG(LOG_WARNING, "replay counter made %d cycle. %s\n", 2028 replay->overflow, ipsec_logsastr(sav, buf, sizeof(buf))); 2029 } 2030 2031 replay->count++; 2032 2033 return 0; 2034 } 2035 2036 /* 2037 * shift variable length buffer to left. 2038 * IN: bitmap: pointer to the buffer 2039 * nbit: the number of to shift. 2040 * wsize: buffer size (bytes). 2041 */ 2042 static void 2043 vshiftl(unsigned char *bitmap, int nbit, int wsize) 2044 { 2045 int s, j, i; 2046 unsigned char over; 2047 2048 for (j = 0; j < nbit; j += 8) { 2049 s = (nbit - j < 8) ? (nbit - j): 8; 2050 bitmap[0] <<= s; 2051 for (i = 1; i < wsize; i++) { 2052 over = (bitmap[i] >> (8 - s)); 2053 bitmap[i] <<= s; 2054 bitmap[i-1] |= over; 2055 } 2056 } 2057 2058 return; 2059 } 2060 2061 /* Return a printable string for the address. */ 2062 const char * 2063 ipsec_address(const union sockaddr_union *sa, char *buf, size_t size) 2064 { 2065 switch (sa->sa.sa_family) { 2066 #if INET 2067 case AF_INET: 2068 in_print(buf, size, &sa->sin.sin_addr); 2069 return buf; 2070 #endif 2071 #if INET6 2072 case AF_INET6: 2073 in6_print(buf, size, &sa->sin6.sin6_addr); 2074 return buf; 2075 #endif 2076 default: 2077 return "(unknown address family)"; 2078 } 2079 } 2080 2081 const char * 2082 ipsec_logsastr(const struct secasvar *sav, char *buf, size_t size) 2083 { 2084 const struct secasindex *saidx = &sav->sah->saidx; 2085 char sbuf[IPSEC_ADDRSTRLEN], dbuf[IPSEC_ADDRSTRLEN]; 2086 2087 KASSERTMSG(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 2088 "af family mismatch, src %u, dst %u", 2089 saidx->src.sa.sa_family, saidx->dst.sa.sa_family); 2090 2091 snprintf(buf, size, "SA(SPI=%u src=%s dst=%s)", 2092 (u_int32_t)ntohl(sav->spi), 2093 ipsec_address(&saidx->src, sbuf, sizeof(sbuf)), 2094 ipsec_address(&saidx->dst, dbuf, sizeof(dbuf))); 2095 2096 return buf; 2097 } 2098 2099 void 2100 ipsec_dumpmbuf(struct mbuf *m) 2101 { 2102 int totlen; 2103 int i; 2104 u_char *p; 2105 2106 totlen = 0; 2107 printf("---\n"); 2108 while (m) { 2109 p = mtod(m, u_char *); 2110 for (i = 0; i < m->m_len; i++) { 2111 printf("%02x ", p[i]); 2112 totlen++; 2113 if (totlen % 16 == 0) 2114 printf("\n"); 2115 } 2116 m = m->m_next; 2117 } 2118 if (totlen % 16 != 0) 2119 printf("\n"); 2120 printf("---\n"); 2121 } 2122 2123 #ifdef INET6 2124 struct secpolicy * 2125 ipsec6_check_policy(struct mbuf *m, struct in6pcb *in6p, int flags, 2126 int *needipsecp, int *errorp) 2127 { 2128 struct secpolicy *sp = NULL; 2129 int s; 2130 int error = 0; 2131 int needipsec = 0; 2132 2133 if (!ipsec_outdone(m)) { 2134 s = splsoftnet(); 2135 if (in6p != NULL && 2136 ipsec_pcb_skip_ipsec(in6p->in6p_sp, IPSEC_DIR_OUTBOUND)) { 2137 splx(s); 2138 goto skippolicycheck; 2139 } 2140 sp = ipsec_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, 2141 in6p); 2142 2143 /* 2144 * There are four return cases: 2145 * sp != NULL apply IPsec policy 2146 * sp == NULL, error == 0 no IPsec handling needed 2147 * sp == NULL, error == -EINVAL discard packet w/o error 2148 * sp == NULL, error != 0 discard packet, report error 2149 */ 2150 2151 splx(s); 2152 if (sp == NULL) { 2153 /* 2154 * Caller must check the error return to see if it needs to discard 2155 * the packet. 2156 */ 2157 needipsec = 0; 2158 } else { 2159 needipsec = 1; 2160 } 2161 } 2162 skippolicycheck:; 2163 2164 *errorp = error; 2165 *needipsecp = needipsec; 2166 return sp; 2167 } 2168 2169 int 2170 ipsec6_input(struct mbuf *m) 2171 { 2172 struct secpolicy *sp; 2173 int s, error; 2174 2175 s = splsoftnet(); 2176 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 2177 if (sp != NULL) { 2178 /* 2179 * Check security policy against packet 2180 * attributes. 2181 */ 2182 error = ipsec_sp_reject(sp, m); 2183 KEY_SP_UNREF(&sp); 2184 } else { 2185 /* XXX error stat??? */ 2186 error = EINVAL; 2187 IPSECLOG(LOG_DEBUG, "no SP, packet discarded\n");/*XXX*/ 2188 } 2189 splx(s); 2190 2191 return error; 2192 } 2193 #endif /* INET6 */ 2194 2195 /* 2196 * ----------------------------------------------------------------------------- 2197 */ 2198 2199 /* XXX this stuff doesn't belong here... */ 2200 2201 static struct xformsw *xforms = NULL; 2202 2203 /* 2204 * Register a transform; typically at system startup. 2205 */ 2206 void 2207 xform_register(struct xformsw *xsp) 2208 { 2209 xsp->xf_next = xforms; 2210 xforms = xsp; 2211 } 2212 2213 /* 2214 * Initialize transform support in an sav. 2215 */ 2216 int 2217 xform_init(struct secasvar *sav, int xftype) 2218 { 2219 struct xformsw *xsp; 2220 2221 if (sav->tdb_xform != NULL) /* previously initialized */ 2222 return 0; 2223 for (xsp = xforms; xsp; xsp = xsp->xf_next) 2224 if (xsp->xf_type == xftype) 2225 return (*xsp->xf_init)(sav, xsp); 2226 2227 IPSECLOG(LOG_DEBUG, "no match for xform type %d\n", xftype); 2228 return EINVAL; 2229 } 2230 2231 void 2232 nat_t_ports_get(struct mbuf *m, u_int16_t *dport, u_int16_t *sport) 2233 { 2234 struct m_tag *tag; 2235 2236 if ((tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL))) { 2237 *sport = ((u_int16_t *)(tag + 1))[0]; 2238 *dport = ((u_int16_t *)(tag + 1))[1]; 2239 } else 2240 *sport = *dport = 0; 2241 } 2242 2243 /* 2244 * XXXJRT This should be done as a protosw init call. 2245 */ 2246 void 2247 ipsec_attach(void) 2248 { 2249 2250 ipsec_output_init(); 2251 2252 ipsecstat_percpu = percpu_alloc(sizeof(uint64_t) * IPSEC_NSTATS); 2253 2254 sysctl_net_inet_ipsec_setup(NULL); 2255 #ifdef INET6 2256 sysctl_net_inet6_ipsec6_setup(NULL); 2257 #endif 2258 2259 ah_attach(); 2260 esp_attach(); 2261 ipcomp_attach(); 2262 ipe4_attach(); 2263 #ifdef TCP_SIGNATURE 2264 tcpsignature_attach(); 2265 #endif 2266 } 2267
Indexes created Wed Sep 24 05:09:52 GMT 2025