ipsec.c revision 1.131
1 /* $NetBSD: ipsec.c,v 1.131 2018/02/16 15:18:41 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 1.131 2018/02/16 15:18:41 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 void vshiftl(unsigned char *, int, int); 193 static size_t ipsec_hdrsiz(const struct secpolicy *, const struct mbuf *); 194 195 /* 196 * Try to validate and use cached policy on a PCB. 197 */ 198 static struct secpolicy * 199 ipsec_checkpcbcache(struct mbuf *m, struct inpcbpolicy *pcbsp, int dir) 200 { 201 struct secpolicyindex spidx; 202 struct secpolicy *sp = NULL; 203 int s; 204 205 KASSERT(IPSEC_DIR_IS_VALID(dir)); 206 KASSERT(pcbsp != NULL); 207 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 208 KASSERT(inph_locked(pcbsp->sp_inph)); 209 210 /* 211 * Checking the generation and sp->state and taking a reference to an SP 212 * must be in a critical section of pserialize. See key_unlink_sp. 213 */ 214 s = pserialize_read_enter(); 215 /* SPD table change invalidate all the caches. */ 216 if (ipsec_spdgen != pcbsp->sp_cache[dir].cachegen) { 217 ipsec_invalpcbcache(pcbsp, dir); 218 goto out; 219 } 220 sp = pcbsp->sp_cache[dir].cachesp; 221 if (sp == NULL) 222 goto out; 223 if (sp->state != IPSEC_SPSTATE_ALIVE) { 224 sp = NULL; 225 ipsec_invalpcbcache(pcbsp, dir); 226 goto out; 227 } 228 if ((pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) == 0) { 229 /* NB: assume ipsec_setspidx never sleep */ 230 if (ipsec_setspidx(m, &spidx, 1) != 0) { 231 sp = NULL; 232 goto out; 233 } 234 235 /* 236 * We have to make an exact match here since the cached rule 237 * might have lower priority than a rule that would otherwise 238 * have matched the packet. 239 */ 240 if (memcmp(&pcbsp->sp_cache[dir].cacheidx, &spidx, 241 sizeof(spidx))) { 242 sp = NULL; 243 goto out; 244 } 245 } else { 246 /* 247 * The pcb is connected, and the L4 code is sure that: 248 * - outgoing side uses inp_[lf]addr 249 * - incoming side looks up policy after inpcb lookup 250 * and address pair is know to be stable. We do not need 251 * to generate spidx again, nor check the address match again. 252 * 253 * For IPv4/v6 SOCK_STREAM sockets, this assumptions holds 254 * and there are calls to ipsec_pcbconn() from in_pcbconnect(). 255 */ 256 } 257 258 sp->lastused = time_second; 259 KEY_SP_REF(sp); 260 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 261 "DP cause refcnt++:%d SP:%p\n", 262 key_sp_refcnt(sp), pcbsp->sp_cache[dir].cachesp); 263 out: 264 pserialize_read_exit(s); 265 return sp; 266 } 267 268 static int 269 ipsec_fillpcbcache(struct inpcbpolicy *pcbsp, struct mbuf *m, 270 struct secpolicy *sp, int dir) 271 { 272 273 KASSERT(IPSEC_DIR_IS_INOROUT(dir)); 274 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 275 KASSERT(inph_locked(pcbsp->sp_inph)); 276 277 pcbsp->sp_cache[dir].cachesp = NULL; 278 pcbsp->sp_cache[dir].cachehint = IPSEC_PCBHINT_UNKNOWN; 279 if (ipsec_setspidx(m, &pcbsp->sp_cache[dir].cacheidx, 1) != 0) { 280 return EINVAL; 281 } 282 pcbsp->sp_cache[dir].cachesp = sp; 283 if (pcbsp->sp_cache[dir].cachesp) { 284 /* 285 * If the PCB is connected, we can remember a hint to 286 * possibly short-circuit IPsec processing in other places. 287 */ 288 if (pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) { 289 switch (pcbsp->sp_cache[dir].cachesp->policy) { 290 case IPSEC_POLICY_NONE: 291 case IPSEC_POLICY_BYPASS: 292 pcbsp->sp_cache[dir].cachehint = 293 IPSEC_PCBHINT_NO; 294 break; 295 default: 296 pcbsp->sp_cache[dir].cachehint = 297 IPSEC_PCBHINT_YES; 298 } 299 } 300 } 301 pcbsp->sp_cache[dir].cachegen = ipsec_spdgen; 302 303 return 0; 304 } 305 306 static int 307 ipsec_invalpcbcache(struct inpcbpolicy *pcbsp, int dir) 308 { 309 int i; 310 311 KASSERT(inph_locked(pcbsp->sp_inph)); 312 313 for (i = IPSEC_DIR_INBOUND; i <= IPSEC_DIR_OUTBOUND; i++) { 314 if (dir != IPSEC_DIR_ANY && i != dir) 315 continue; 316 pcbsp->sp_cache[i].cachesp = NULL; 317 pcbsp->sp_cache[i].cachehint = IPSEC_PCBHINT_UNKNOWN; 318 pcbsp->sp_cache[i].cachegen = 0; 319 memset(&pcbsp->sp_cache[i].cacheidx, 0, 320 sizeof(pcbsp->sp_cache[i].cacheidx)); 321 } 322 return 0; 323 } 324 325 void 326 ipsec_pcbconn(struct inpcbpolicy *pcbsp) 327 { 328 329 KASSERT(inph_locked(pcbsp->sp_inph)); 330 331 pcbsp->sp_cacheflags |= IPSEC_PCBSP_CONNECTED; 332 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 333 } 334 335 void 336 ipsec_pcbdisconn(struct inpcbpolicy *pcbsp) 337 { 338 339 KASSERT(inph_locked(pcbsp->sp_inph)); 340 341 pcbsp->sp_cacheflags &= ~IPSEC_PCBSP_CONNECTED; 342 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 343 } 344 345 void 346 ipsec_invalpcbcacheall(void) 347 { 348 349 if (ipsec_spdgen == UINT_MAX) 350 ipsec_spdgen = 1; 351 else 352 ipsec_spdgen++; 353 } 354 355 /* 356 * Return a held reference to the default SP. 357 */ 358 static struct secpolicy * 359 key_get_default_sp(int af, const char *where, int tag) 360 { 361 struct secpolicy *sp; 362 363 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP from %s:%u\n", where, tag); 364 365 switch(af) { 366 case AF_INET: 367 sp = &ip4_def_policy; 368 break; 369 #ifdef INET6 370 case AF_INET6: 371 sp = &ip6_def_policy; 372 break; 373 #endif 374 default: 375 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 376 "unexpected protocol family %u\n", af); 377 return NULL; 378 } 379 380 if (sp->policy != IPSEC_POLICY_DISCARD && 381 sp->policy != IPSEC_POLICY_NONE) { 382 IPSECLOG(LOG_INFO, "fixed system default policy: %d->%d\n", 383 sp->policy, IPSEC_POLICY_NONE); 384 sp->policy = IPSEC_POLICY_NONE; 385 } 386 KEY_SP_REF(sp); 387 388 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP returns SP:%p (%u)\n", 389 sp, key_sp_refcnt(sp)); 390 return sp; 391 } 392 393 #define KEY_GET_DEFAULT_SP(af) \ 394 key_get_default_sp((af), __func__, __LINE__) 395 396 /* 397 * For OUTBOUND packet having a socket. Searching SPD for packet, 398 * and return a pointer to SP. 399 * OUT: NULL: no apropreate SP found, the following value is set to error. 400 * 0 : bypass 401 * EACCES : discard packet. 402 * ENOENT : ipsec_acquire() in progress, maybe. 403 * others : error occurred. 404 * others: a pointer to SP 405 * 406 * NOTE: IPv6 mapped address concern is implemented here. 407 */ 408 static struct secpolicy * 409 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb_hdr *inph, 410 int *error) 411 { 412 struct inpcbpolicy *pcbsp = NULL; 413 struct secpolicy *currsp = NULL; /* policy on socket */ 414 struct secpolicy *sp; 415 int af; 416 417 KASSERT(m != NULL); 418 KASSERT(inph != NULL); 419 KASSERT(error != NULL); 420 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 421 422 KASSERT(inph->inph_socket != NULL); 423 KASSERT(inph_locked(inph)); 424 425 /* XXX FIXME inpcb/in6pcb vs socket*/ 426 af = inph->inph_af; 427 KASSERTMSG(af == AF_INET || af == AF_INET6, 428 "unexpected protocol family %u", af); 429 430 KASSERT(inph->inph_sp != NULL); 431 /* If we have a cached entry, and if it is still valid, use it. */ 432 IPSEC_STATINC(IPSEC_STAT_SPDCACHELOOKUP); 433 currsp = ipsec_checkpcbcache(m, inph->inph_sp, dir); 434 if (currsp) { 435 *error = 0; 436 return currsp; 437 } 438 IPSEC_STATINC(IPSEC_STAT_SPDCACHEMISS); 439 440 switch (af) { 441 case AF_INET: { 442 struct inpcb *in4p = (struct inpcb *)inph; 443 /* set spidx in pcb */ 444 *error = ipsec4_setspidx_inpcb(m, in4p); 445 pcbsp = in4p->inp_sp; 446 break; 447 } 448 #if defined(INET6) 449 case AF_INET6: { 450 struct in6pcb *in6p = (struct in6pcb *)inph; 451 /* set spidx in pcb */ 452 *error = ipsec6_setspidx_in6pcb(m, in6p); 453 pcbsp = in6p->in6p_sp; 454 break; 455 } 456 #endif 457 default: 458 *error = EPFNOSUPPORT; 459 break; 460 } 461 if (*error) 462 return NULL; 463 464 KASSERT(pcbsp != NULL); 465 switch (dir) { 466 case IPSEC_DIR_INBOUND: 467 currsp = pcbsp->sp_in; 468 break; 469 case IPSEC_DIR_OUTBOUND: 470 currsp = pcbsp->sp_out; 471 break; 472 } 473 KASSERT(currsp != NULL); 474 475 if (pcbsp->priv) { /* when privilieged socket */ 476 switch (currsp->policy) { 477 case IPSEC_POLICY_BYPASS: 478 case IPSEC_POLICY_IPSEC: 479 KEY_SP_REF(currsp); 480 sp = currsp; 481 break; 482 483 case IPSEC_POLICY_ENTRUST: 484 /* look for a policy in SPD */ 485 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 486 if (sp == NULL) /* no SP found */ 487 sp = KEY_GET_DEFAULT_SP(af); 488 break; 489 490 default: 491 IPSECLOG(LOG_ERR, "Invalid policy for PCB %d\n", 492 currsp->policy); 493 *error = EINVAL; 494 return NULL; 495 } 496 } else { /* unpriv, SPD has policy */ 497 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 498 if (sp == NULL) { /* no SP found */ 499 switch (currsp->policy) { 500 case IPSEC_POLICY_BYPASS: 501 IPSECLOG(LOG_ERR, "Illegal policy for " 502 "non-priviliged defined %d\n", 503 currsp->policy); 504 *error = EINVAL; 505 return NULL; 506 507 case IPSEC_POLICY_ENTRUST: 508 sp = KEY_GET_DEFAULT_SP(af); 509 break; 510 511 case IPSEC_POLICY_IPSEC: 512 KEY_SP_REF(currsp); 513 sp = currsp; 514 break; 515 516 default: 517 IPSECLOG(LOG_ERR, "Invalid policy for " 518 "PCB %d\n", currsp->policy); 519 *error = EINVAL; 520 return NULL; 521 } 522 } 523 } 524 KASSERTMSG(sp != NULL, "null SP (priv %u policy %u", pcbsp->priv, 525 currsp->policy); 526 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 527 "DP (priv %u policy %u) allocates SP:%p (refcnt %u)\n", 528 pcbsp->priv, currsp->policy, sp, key_sp_refcnt(sp)); 529 ipsec_fillpcbcache(pcbsp, m, sp, dir); 530 return sp; 531 } 532 533 /* 534 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 535 * and return a pointer to SP. 536 * OUT: positive: a pointer to the entry for security policy leaf matched. 537 * NULL: no apropreate SP found, the following value is set to error. 538 * 0 : bypass 539 * EACCES : discard packet. 540 * ENOENT : ipsec_acquire() in progress, maybe. 541 * others : error occurred. 542 */ 543 static struct secpolicy * 544 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 545 { 546 struct secpolicyindex spidx; 547 struct secpolicy *sp; 548 549 KASSERT(m != NULL); 550 KASSERT(error != NULL); 551 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 552 553 sp = NULL; 554 555 /* Make an index to look for a policy. */ 556 *error = ipsec_setspidx(m, &spidx, (flag & IP_FORWARDING) ? 0 : 1); 557 if (*error != 0) { 558 IPSECLOG(LOG_DEBUG, "setpidx failed, dir %u flag %u\n", dir, flag); 559 memset(&spidx, 0, sizeof(spidx)); 560 return NULL; 561 } 562 563 spidx.dir = dir; 564 565 if (key_havesp(dir)) { 566 sp = KEY_LOOKUP_SP_BYSPIDX(&spidx, dir); 567 } 568 569 if (sp == NULL) /* no SP found, use system default */ 570 sp = KEY_GET_DEFAULT_SP(spidx.dst.sa.sa_family); 571 KASSERT(sp != NULL); 572 return sp; 573 } 574 575 static struct secpolicy * 576 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 577 struct inpcb *inp) 578 { 579 struct secpolicy *sp; 580 581 *error = 0; 582 583 if (inp == NULL) { 584 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 585 } else { 586 KASSERT(inp->inp_socket != NULL); 587 sp = ipsec_getpolicybysock(m, dir, (struct inpcb_hdr *)inp, error); 588 } 589 if (sp == NULL) { 590 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 591 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 592 return NULL; 593 } 594 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 595 switch (sp->policy) { 596 case IPSEC_POLICY_ENTRUST: 597 default: 598 printf("%s: invalid policy %u\n", __func__, sp->policy); 599 /* fall thru... */ 600 case IPSEC_POLICY_DISCARD: 601 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 602 *error = -EINVAL; /* packet is discarded by caller */ 603 break; 604 case IPSEC_POLICY_BYPASS: 605 case IPSEC_POLICY_NONE: 606 KEY_SP_UNREF(&sp); 607 sp = NULL; /* NB: force NULL result */ 608 break; 609 case IPSEC_POLICY_IPSEC: 610 KASSERT(sp->req != NULL); 611 break; 612 } 613 if (*error != 0) { 614 KEY_SP_UNREF(&sp); 615 sp = NULL; 616 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 617 } 618 return sp; 619 } 620 621 int 622 ipsec4_output(struct mbuf *m, struct inpcb *inp, int flags, 623 u_long *mtu, bool *natt_frag, bool *done) 624 { 625 struct secpolicy *sp = NULL; 626 int error, s; 627 628 /* 629 * Check the security policy (SP) for the packet and, if required, 630 * do IPsec-related processing. There are two cases here; the first 631 * time a packet is sent through it will be untagged and handled by 632 * ipsec4_checkpolicy(). If the packet is resubmitted to ip_output 633 * (e.g. after AH, ESP, etc. processing), there will be a tag to 634 * bypass the lookup and related policy checking. 635 */ 636 if (ipsec_outdone(m)) { 637 return 0; 638 } 639 s = splsoftnet(); 640 if (inp && ipsec_pcb_skip_ipsec(inp->inp_sp, IPSEC_DIR_OUTBOUND)) { 641 splx(s); 642 return 0; 643 } 644 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, inp); 645 646 /* 647 * There are four return cases: 648 * sp != NULL apply IPsec policy 649 * sp == NULL, error == 0 no IPsec handling needed 650 * sp == NULL, error == -EINVAL discard packet w/o error 651 * sp == NULL, error != 0 discard packet, report error 652 */ 653 if (sp == NULL) { 654 splx(s); 655 if (error) { 656 /* 657 * Hack: -EINVAL is used to signal that a packet 658 * should be silently discarded. This is typically 659 * because we asked key management for an SA and 660 * it was delayed (e.g. kicked up to IKE). 661 */ 662 if (error == -EINVAL) 663 error = 0; 664 m_freem(m); 665 *done = true; 666 return error; 667 } 668 /* No IPsec processing for this packet. */ 669 return 0; 670 } 671 672 /* 673 * Do delayed checksums now because we send before 674 * this is done in the normal processing path. 675 */ 676 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 677 in_delayed_cksum(m); 678 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 679 } 680 681 { 682 u_long _mtu = 0; 683 684 /* Note: callee frees mbuf */ 685 error = ipsec4_process_packet(m, sp->req, &_mtu); 686 687 if (error == 0 && _mtu != 0) { 688 /* 689 * NAT-T ESP fragmentation: do not do IPSec processing 690 * now, we will do it on each fragmented packet. 691 */ 692 *mtu = _mtu; 693 *natt_frag = true; 694 KEY_SP_UNREF(&sp); 695 splx(s); 696 return 0; 697 } 698 } 699 /* 700 * Preserve KAME behaviour: ENOENT can be returned 701 * when an SA acquire is in progress. Don't propagate 702 * this to user-level; it confuses applications. 703 * 704 * XXX this will go away when the SADB is redone. 705 */ 706 if (error == ENOENT) 707 error = 0; 708 KEY_SP_UNREF(&sp); 709 splx(s); 710 *done = true; 711 return error; 712 } 713 714 int 715 ipsec4_input(struct mbuf *m, int flags) 716 { 717 struct secpolicy *sp; 718 int error, s; 719 720 s = splsoftnet(); 721 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 722 if (sp == NULL) { 723 splx(s); 724 return EINVAL; 725 } 726 727 /* 728 * Check security policy against packet attributes. 729 */ 730 error = ipsec_in_reject(sp, m); 731 KEY_SP_UNREF(&sp); 732 splx(s); 733 if (error) { 734 return error; 735 } 736 737 if (flags == 0) { 738 /* We are done. */ 739 return 0; 740 } 741 742 /* 743 * Peek at the outbound SP for this packet to determine if 744 * it is a Fast Forward candidate. 745 */ 746 s = splsoftnet(); 747 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, NULL); 748 if (sp != NULL) { 749 m->m_flags &= ~M_CANFASTFWD; 750 KEY_SP_UNREF(&sp); 751 } 752 splx(s); 753 return 0; 754 } 755 756 int 757 ipsec4_forward(struct mbuf *m, int *destmtu) 758 { 759 /* 760 * If the packet is routed over IPsec tunnel, tell the 761 * originator the tunnel MTU. 762 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 763 * XXX quickhack!!! 764 */ 765 struct secpolicy *sp; 766 size_t ipsechdr; 767 int error; 768 769 sp = ipsec_getpolicybyaddr(m, 770 IPSEC_DIR_OUTBOUND, IP_FORWARDING, &error); 771 if (sp == NULL) { 772 return EINVAL; 773 } 774 775 /* Count IPsec header size. */ 776 ipsechdr = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, NULL); 777 778 /* 779 * Find the correct route for outer IPv4 header, compute tunnel MTU. 780 */ 781 if (sp->req) { 782 struct secasvar *sav; 783 784 sav = ipsec_lookup_sa(sp->req, m); 785 if (sav != NULL) { 786 struct route *ro; 787 struct rtentry *rt; 788 789 ro = &sav->sah->sa_route; 790 rt = rtcache_validate(ro); 791 if (rt && rt->rt_ifp) { 792 *destmtu = rt->rt_rmx.rmx_mtu ? 793 rt->rt_rmx.rmx_mtu : rt->rt_ifp->if_mtu; 794 *destmtu -= ipsechdr; 795 } 796 rtcache_unref(rt, ro); 797 KEY_SA_UNREF(&sav); 798 } 799 } 800 KEY_SP_UNREF(&sp); 801 return 0; 802 } 803 804 #ifdef INET6 805 struct secpolicy * 806 ipsec6_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 807 struct in6pcb *in6p) 808 { 809 struct secpolicy *sp; 810 811 *error = 0; 812 813 if (in6p == NULL) { 814 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 815 } else { 816 KASSERT(in6p->in6p_socket != NULL); 817 sp = ipsec_getpolicybysock(m, dir, (struct inpcb_hdr *)in6p, error); 818 } 819 if (sp == NULL) { 820 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 821 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 822 return NULL; 823 } 824 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 825 switch (sp->policy) { 826 case IPSEC_POLICY_ENTRUST: 827 default: 828 printf("%s: invalid policy %u\n", __func__, sp->policy); 829 /* fall thru... */ 830 case IPSEC_POLICY_DISCARD: 831 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 832 *error = -EINVAL; /* packet is discarded by caller */ 833 break; 834 case IPSEC_POLICY_BYPASS: 835 case IPSEC_POLICY_NONE: 836 KEY_SP_UNREF(&sp); 837 sp = NULL; /* NB: force NULL result */ 838 break; 839 case IPSEC_POLICY_IPSEC: 840 KASSERT(sp->req != NULL); 841 break; 842 } 843 if (*error != 0) { 844 KEY_SP_UNREF(&sp); 845 sp = NULL; 846 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 847 } 848 return sp; 849 } 850 #endif /* INET6 */ 851 852 static int 853 ipsec4_setspidx_inpcb(struct mbuf *m, struct inpcb *pcb) 854 { 855 int error; 856 857 KASSERT(pcb != NULL); 858 KASSERT(pcb->inp_sp != NULL); 859 KASSERT(pcb->inp_sp->sp_out != NULL); 860 KASSERT(pcb->inp_sp->sp_in != NULL); 861 862 error = ipsec_setspidx(m, &pcb->inp_sp->sp_in->spidx, 1); 863 if (error == 0) { 864 pcb->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 865 pcb->inp_sp->sp_out->spidx = pcb->inp_sp->sp_in->spidx; 866 pcb->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 867 } else { 868 memset(&pcb->inp_sp->sp_in->spidx, 0, 869 sizeof(pcb->inp_sp->sp_in->spidx)); 870 memset(&pcb->inp_sp->sp_out->spidx, 0, 871 sizeof(pcb->inp_sp->sp_in->spidx)); 872 } 873 return error; 874 } 875 876 #ifdef INET6 877 static int 878 ipsec6_setspidx_in6pcb(struct mbuf *m, struct in6pcb *pcb) 879 { 880 struct secpolicyindex *spidx; 881 int error; 882 883 KASSERT(pcb != NULL); 884 KASSERT(pcb->in6p_sp != NULL); 885 KASSERT(pcb->in6p_sp->sp_out != NULL); 886 KASSERT(pcb->in6p_sp->sp_in != NULL); 887 888 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 889 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 890 891 spidx = &pcb->in6p_sp->sp_in->spidx; 892 error = ipsec_setspidx(m, spidx, 1); 893 if (error) 894 goto bad; 895 spidx->dir = IPSEC_DIR_INBOUND; 896 897 spidx = &pcb->in6p_sp->sp_out->spidx; 898 error = ipsec_setspidx(m, spidx, 1); 899 if (error) 900 goto bad; 901 spidx->dir = IPSEC_DIR_OUTBOUND; 902 903 return 0; 904 905 bad: 906 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 907 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 908 return error; 909 } 910 #endif 911 912 /* 913 * configure security policy index (src/dst/proto/sport/dport) 914 * by looking at the content of mbuf. 915 * the caller is responsible for error recovery (like clearing up spidx). 916 */ 917 static int 918 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 919 { 920 struct ip *ip = NULL; 921 struct ip ipbuf; 922 u_int v; 923 struct mbuf *n; 924 int len; 925 int error; 926 927 KASSERT(m != NULL); 928 929 /* 930 * validate m->m_pkthdr.len. we see incorrect length if we 931 * mistakenly call this function with inconsistent mbuf chain 932 * (like 4.4BSD tcp/udp processing). XXX should we panic here? 933 */ 934 len = 0; 935 for (n = m; n; n = n->m_next) 936 len += n->m_len; 937 if (m->m_pkthdr.len != len) { 938 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 939 "total of m_len(%d) != pkthdr.len(%d), ignored.\n", 940 len, m->m_pkthdr.len); 941 return EINVAL; 942 } 943 944 if (m->m_pkthdr.len < sizeof(struct ip)) { 945 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 946 "pkthdr.len(%d) < sizeof(struct ip), ignored.\n", 947 m->m_pkthdr.len); 948 return EINVAL; 949 } 950 951 if (m->m_len >= sizeof(*ip)) { 952 ip = mtod(m, struct ip *); 953 } else { 954 m_copydata(m, 0, sizeof(ipbuf), &ipbuf); 955 ip = &ipbuf; 956 } 957 v = ip->ip_v; 958 switch (v) { 959 case 4: 960 error = ipsec4_setspidx_ipaddr(m, spidx); 961 if (error) 962 return error; 963 ipsec4_get_ulp(m, spidx, needport); 964 return 0; 965 #ifdef INET6 966 case 6: 967 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 968 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 969 "pkthdr.len(%d) < sizeof(struct ip6_hdr), " 970 "ignored.\n", m->m_pkthdr.len); 971 return EINVAL; 972 } 973 error = ipsec6_setspidx_ipaddr(m, spidx); 974 if (error) 975 return error; 976 ipsec6_get_ulp(m, spidx, needport); 977 return 0; 978 #endif 979 default: 980 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 981 "unknown IP version %u, ignored.\n", v); 982 return EINVAL; 983 } 984 } 985 986 static void 987 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 988 { 989 u_int8_t nxt; 990 int off; 991 992 /* sanity check */ 993 KASSERT(m != NULL); 994 KASSERTMSG(m->m_pkthdr.len >= sizeof(struct ip), "packet too short"); 995 996 /* NB: ip_input() flips it into host endian XXX need more checking */ 997 if (m->m_len >= sizeof(struct ip)) { 998 struct ip *ip = mtod(m, struct ip *); 999 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 1000 goto done; 1001 off = ip->ip_hl << 2; 1002 nxt = ip->ip_p; 1003 } else { 1004 struct ip ih; 1005 1006 m_copydata(m, 0, sizeof(struct ip), &ih); 1007 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 1008 goto done; 1009 off = ih.ip_hl << 2; 1010 nxt = ih.ip_p; 1011 } 1012 1013 while (off < m->m_pkthdr.len) { 1014 struct ip6_ext ip6e; 1015 struct tcphdr th; 1016 struct udphdr uh; 1017 struct icmp icmph; 1018 1019 switch (nxt) { 1020 case IPPROTO_TCP: 1021 spidx->ul_proto = nxt; 1022 if (!needport) 1023 goto done_proto; 1024 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1025 goto done; 1026 m_copydata(m, off, sizeof(th), &th); 1027 spidx->src.sin.sin_port = th.th_sport; 1028 spidx->dst.sin.sin_port = th.th_dport; 1029 return; 1030 case IPPROTO_UDP: 1031 spidx->ul_proto = nxt; 1032 if (!needport) 1033 goto done_proto; 1034 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1035 goto done; 1036 m_copydata(m, off, sizeof(uh), &uh); 1037 spidx->src.sin.sin_port = uh.uh_sport; 1038 spidx->dst.sin.sin_port = uh.uh_dport; 1039 return; 1040 case IPPROTO_AH: 1041 if (off + sizeof(ip6e) > m->m_pkthdr.len) 1042 goto done; 1043 /* XXX sigh, this works but is totally bogus */ 1044 m_copydata(m, off, sizeof(ip6e), &ip6e); 1045 off += (ip6e.ip6e_len + 2) << 2; 1046 nxt = ip6e.ip6e_nxt; 1047 break; 1048 case IPPROTO_ICMP: 1049 spidx->ul_proto = nxt; 1050 if (off + sizeof(struct icmp) > m->m_pkthdr.len) 1051 return; 1052 m_copydata(m, off, sizeof(icmph), &icmph); 1053 ((struct sockaddr_in *)&spidx->src)->sin_port = 1054 htons((uint16_t)icmph.icmp_type); 1055 ((struct sockaddr_in *)&spidx->dst)->sin_port = 1056 htons((uint16_t)icmph.icmp_code); 1057 return; 1058 default: 1059 /* XXX intermediate headers??? */ 1060 spidx->ul_proto = nxt; 1061 goto done_proto; 1062 } 1063 } 1064 done: 1065 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1066 done_proto: 1067 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 1068 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 1069 } 1070 1071 /* assumes that m is sane */ 1072 static int 1073 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1074 { 1075 static const struct sockaddr_in template = { 1076 sizeof(struct sockaddr_in), 1077 AF_INET, 1078 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 1079 }; 1080 1081 spidx->src.sin = template; 1082 spidx->dst.sin = template; 1083 1084 if (m->m_len < sizeof(struct ip)) { 1085 m_copydata(m, offsetof(struct ip, ip_src), 1086 sizeof(struct in_addr), &spidx->src.sin.sin_addr); 1087 m_copydata(m, offsetof(struct ip, ip_dst), 1088 sizeof(struct in_addr), &spidx->dst.sin.sin_addr); 1089 } else { 1090 struct ip *ip = mtod(m, struct ip *); 1091 spidx->src.sin.sin_addr = ip->ip_src; 1092 spidx->dst.sin.sin_addr = ip->ip_dst; 1093 } 1094 1095 spidx->prefs = sizeof(struct in_addr) << 3; 1096 spidx->prefd = sizeof(struct in_addr) << 3; 1097 1098 return 0; 1099 } 1100 1101 #ifdef INET6 1102 static void 1103 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 1104 { 1105 int off, nxt; 1106 struct tcphdr th; 1107 struct udphdr uh; 1108 struct icmp6_hdr icmph; 1109 1110 KASSERT(m != NULL); 1111 1112 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1113 kdebug_mbuf(__func__, m); 1114 } 1115 1116 /* set default */ 1117 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1118 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 1119 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 1120 1121 nxt = -1; 1122 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 1123 if (off < 0 || m->m_pkthdr.len < off) 1124 return; 1125 1126 switch (nxt) { 1127 case IPPROTO_TCP: 1128 spidx->ul_proto = nxt; 1129 if (!needport) 1130 break; 1131 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1132 break; 1133 m_copydata(m, off, sizeof(th), &th); 1134 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 1135 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 1136 break; 1137 case IPPROTO_UDP: 1138 spidx->ul_proto = nxt; 1139 if (!needport) 1140 break; 1141 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1142 break; 1143 m_copydata(m, off, sizeof(uh), &uh); 1144 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 1145 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 1146 break; 1147 case IPPROTO_ICMPV6: 1148 spidx->ul_proto = nxt; 1149 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 1150 break; 1151 m_copydata(m, off, sizeof(icmph), &icmph); 1152 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 1153 htons((uint16_t)icmph.icmp6_type); 1154 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 1155 htons((uint16_t)icmph.icmp6_code); 1156 break; 1157 default: 1158 /* XXX intermediate headers??? */ 1159 spidx->ul_proto = nxt; 1160 break; 1161 } 1162 } 1163 1164 /* assumes that m is sane */ 1165 static int 1166 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1167 { 1168 struct ip6_hdr *ip6 = NULL; 1169 struct ip6_hdr ip6buf; 1170 struct sockaddr_in6 *sin6; 1171 1172 if (m->m_len >= sizeof(*ip6)) 1173 ip6 = mtod(m, struct ip6_hdr *); 1174 else { 1175 m_copydata(m, 0, sizeof(ip6buf), &ip6buf); 1176 ip6 = &ip6buf; 1177 } 1178 1179 sin6 = (struct sockaddr_in6 *)&spidx->src; 1180 memset(sin6, 0, sizeof(*sin6)); 1181 sin6->sin6_family = AF_INET6; 1182 sin6->sin6_len = sizeof(struct sockaddr_in6); 1183 memcpy(&sin6->sin6_addr, &ip6->ip6_src, sizeof(ip6->ip6_src)); 1184 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 1185 sin6->sin6_addr.s6_addr16[1] = 0; 1186 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 1187 } 1188 spidx->prefs = sizeof(struct in6_addr) << 3; 1189 1190 sin6 = (struct sockaddr_in6 *)&spidx->dst; 1191 memset(sin6, 0, sizeof(*sin6)); 1192 sin6->sin6_family = AF_INET6; 1193 sin6->sin6_len = sizeof(struct sockaddr_in6); 1194 memcpy(&sin6->sin6_addr, &ip6->ip6_dst, sizeof(ip6->ip6_dst)); 1195 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 1196 sin6->sin6_addr.s6_addr16[1] = 0; 1197 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 1198 } 1199 spidx->prefd = sizeof(struct in6_addr) << 3; 1200 1201 return 0; 1202 } 1203 #endif 1204 1205 static void 1206 ipsec_delpcbpolicy(struct inpcbpolicy *p) 1207 { 1208 1209 kmem_intr_free(p, sizeof(*p)); 1210 } 1211 1212 /* initialize policy in PCB */ 1213 int 1214 ipsec_init_policy(struct socket *so, struct inpcbpolicy **policy) 1215 { 1216 struct inpcbpolicy *new; 1217 1218 KASSERT(so != NULL); 1219 KASSERT(policy != NULL); 1220 1221 new = kmem_intr_zalloc(sizeof(*new), KM_NOSLEEP); 1222 if (new == NULL) { 1223 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1224 return ENOBUFS; 1225 } 1226 1227 if (IPSEC_PRIVILEGED_SO(so)) 1228 new->priv = 1; 1229 else 1230 new->priv = 0; 1231 1232 /* 1233 * Set dummy SPs. Actual SPs will be allocated later if needed. 1234 */ 1235 new->sp_in = &ipsec_dummy_sp; 1236 new->sp_out = &ipsec_dummy_sp; 1237 1238 *policy = new; 1239 1240 return 0; 1241 } 1242 1243 #if 0 /* unused */ 1244 /* copy old ipsec policy into new */ 1245 int 1246 ipsec_copy_policy(const struct inpcbpolicy *old, struct inpcbpolicy *new) 1247 { 1248 struct secpolicy *sp; 1249 1250 sp = ipsec_deepcopy_policy(old->sp_in); 1251 if (sp) { 1252 KEY_SP_UNREF(&new->sp_in); 1253 new->sp_in = sp; 1254 } else 1255 return ENOBUFS; 1256 1257 sp = ipsec_deepcopy_policy(old->sp_out); 1258 if (sp) { 1259 KEY_SP_UNREF(&new->sp_out); 1260 new->sp_out = sp; 1261 } else 1262 return ENOBUFS; 1263 1264 new->priv = old->priv; 1265 1266 return 0; 1267 } 1268 1269 /* deep-copy a policy in PCB */ 1270 static struct secpolicy * 1271 ipsec_deepcopy_policy(const struct secpolicy *src) 1272 { 1273 struct ipsecrequest *newchain = NULL; 1274 const struct ipsecrequest *p; 1275 struct ipsecrequest **q; 1276 struct secpolicy *dst; 1277 1278 if (src == NULL) 1279 return NULL; 1280 dst = KEY_NEWSP(); 1281 if (dst == NULL) 1282 return NULL; 1283 1284 /* 1285 * deep-copy IPsec request chain. This is required since struct 1286 * ipsecrequest is not reference counted. 1287 */ 1288 q = &newchain; 1289 for (p = src->req; p; p = p->next) { 1290 *q = kmem_zalloc(sizeof(**q), KM_SLEEP); 1291 (*q)->next = NULL; 1292 1293 (*q)->saidx.proto = p->saidx.proto; 1294 (*q)->saidx.mode = p->saidx.mode; 1295 (*q)->level = p->level; 1296 (*q)->saidx.reqid = p->saidx.reqid; 1297 1298 memcpy(&(*q)->saidx.src, &p->saidx.src, sizeof((*q)->saidx.src)); 1299 memcpy(&(*q)->saidx.dst, &p->saidx.dst, sizeof((*q)->saidx.dst)); 1300 1301 (*q)->sp = dst; 1302 1303 q = &((*q)->next); 1304 } 1305 1306 dst->req = newchain; 1307 dst->state = src->state; 1308 dst->policy = src->policy; 1309 /* do not touch the refcnt fields */ 1310 1311 return dst; 1312 } 1313 #endif 1314 1315 static void 1316 ipsec_destroy_policy(struct secpolicy *sp) 1317 { 1318 1319 if (sp == &ipsec_dummy_sp) 1320 ; /* It's dummy. No need to free it. */ 1321 else { 1322 /* 1323 * We cannot destroy here because it can be called in 1324 * softint. So mark the SP as DEAD and let the timer 1325 * destroy it. See key_timehandler_spd. 1326 */ 1327 sp->state = IPSEC_SPSTATE_DEAD; 1328 } 1329 } 1330 1331 /* set policy and ipsec request if present. */ 1332 static int 1333 ipsec_set_policy(struct secpolicy **policy, int optname, const void *request, 1334 size_t len, kauth_cred_t cred) 1335 { 1336 const struct sadb_x_policy *xpl; 1337 struct secpolicy *newsp = NULL, *oldsp; 1338 int error; 1339 1340 KASSERT(!cpu_softintr_p()); 1341 1342 /* sanity check. */ 1343 if (policy == NULL || *policy == NULL || request == NULL) 1344 return EINVAL; 1345 if (len < sizeof(*xpl)) 1346 return EINVAL; 1347 xpl = (const struct sadb_x_policy *)request; 1348 1349 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1350 kdebug_sadb_xpolicy("set passed policy", request); 1351 } 1352 1353 /* check policy type */ 1354 /* ipsec_set_policy() accepts IPSEC, ENTRUST and BYPASS. */ 1355 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD || 1356 xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1357 return EINVAL; 1358 1359 /* check privileged socket */ 1360 if (xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1361 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPSEC, 1362 KAUTH_REQ_NETWORK_IPSEC_BYPASS, NULL, NULL, NULL); 1363 if (error) 1364 return error; 1365 } 1366 1367 /* allocation new SP entry */ 1368 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1369 return error; 1370 1371 key_init_sp(newsp); 1372 newsp->created = time_uptime; 1373 /* Insert the global list for SPs for sockets */ 1374 key_socksplist_add(newsp); 1375 1376 /* clear old SP and set new SP */ 1377 oldsp = *policy; 1378 *policy = newsp; 1379 ipsec_destroy_policy(oldsp); 1380 1381 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1382 printf("%s: new policy\n", __func__); 1383 kdebug_secpolicy(newsp); 1384 } 1385 1386 return 0; 1387 } 1388 1389 static int 1390 ipsec_get_policy(struct secpolicy *policy, struct mbuf **mp) 1391 { 1392 1393 /* sanity check. */ 1394 if (policy == NULL || mp == NULL) 1395 return EINVAL; 1396 1397 *mp = key_sp2msg(policy, M_NOWAIT); 1398 if (!*mp) { 1399 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1400 return ENOBUFS; 1401 } 1402 1403 (*mp)->m_type = MT_DATA; 1404 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1405 kdebug_mbuf(__func__, *mp); 1406 } 1407 1408 return 0; 1409 } 1410 1411 int 1412 ipsec4_set_policy(struct inpcb *inp, int optname, const void *request, 1413 size_t len, kauth_cred_t cred) 1414 { 1415 const struct sadb_x_policy *xpl; 1416 struct secpolicy **policy; 1417 1418 KASSERT(!cpu_softintr_p()); 1419 KASSERT(inp != NULL); 1420 KASSERT(inp_locked(inp)); 1421 KASSERT(request != NULL); 1422 1423 if (len < sizeof(*xpl)) 1424 return EINVAL; 1425 xpl = (const struct sadb_x_policy *)request; 1426 1427 KASSERT(inp->inp_sp != NULL); 1428 1429 /* select direction */ 1430 switch (xpl->sadb_x_policy_dir) { 1431 case IPSEC_DIR_INBOUND: 1432 policy = &inp->inp_sp->sp_in; 1433 break; 1434 case IPSEC_DIR_OUTBOUND: 1435 policy = &inp->inp_sp->sp_out; 1436 break; 1437 default: 1438 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1439 xpl->sadb_x_policy_dir); 1440 return EINVAL; 1441 } 1442 1443 return ipsec_set_policy(policy, optname, request, len, cred); 1444 } 1445 1446 int 1447 ipsec4_get_policy(struct inpcb *inp, const void *request, size_t len, 1448 struct mbuf **mp) 1449 { 1450 const struct sadb_x_policy *xpl; 1451 struct secpolicy *policy; 1452 1453 /* sanity check. */ 1454 if (inp == NULL || request == NULL || mp == NULL) 1455 return EINVAL; 1456 KASSERT(inp->inp_sp != NULL); 1457 if (len < sizeof(*xpl)) 1458 return EINVAL; 1459 xpl = (const struct sadb_x_policy *)request; 1460 1461 /* select direction */ 1462 switch (xpl->sadb_x_policy_dir) { 1463 case IPSEC_DIR_INBOUND: 1464 policy = inp->inp_sp->sp_in; 1465 break; 1466 case IPSEC_DIR_OUTBOUND: 1467 policy = inp->inp_sp->sp_out; 1468 break; 1469 default: 1470 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1471 xpl->sadb_x_policy_dir); 1472 return EINVAL; 1473 } 1474 1475 return ipsec_get_policy(policy, mp); 1476 } 1477 1478 /* delete policy in PCB */ 1479 int 1480 ipsec4_delete_pcbpolicy(struct inpcb *inp) 1481 { 1482 1483 KASSERT(inp != NULL); 1484 1485 if (inp->inp_sp == NULL) 1486 return 0; 1487 1488 if (inp->inp_sp->sp_in != NULL) 1489 ipsec_destroy_policy(inp->inp_sp->sp_in); 1490 1491 if (inp->inp_sp->sp_out != NULL) 1492 ipsec_destroy_policy(inp->inp_sp->sp_out); 1493 1494 ipsec_invalpcbcache(inp->inp_sp, IPSEC_DIR_ANY); 1495 1496 ipsec_delpcbpolicy(inp->inp_sp); 1497 inp->inp_sp = NULL; 1498 1499 return 0; 1500 } 1501 1502 #ifdef INET6 1503 int 1504 ipsec6_set_policy(struct in6pcb *in6p, int optname, const void *request, 1505 size_t len, kauth_cred_t cred) 1506 { 1507 const struct sadb_x_policy *xpl; 1508 struct secpolicy **policy; 1509 1510 KASSERT(!cpu_softintr_p()); 1511 KASSERT(in6p_locked(in6p)); 1512 1513 /* sanity check. */ 1514 if (in6p == NULL || request == NULL) 1515 return EINVAL; 1516 if (len < sizeof(*xpl)) 1517 return EINVAL; 1518 xpl = (const struct sadb_x_policy *)request; 1519 1520 /* select direction */ 1521 switch (xpl->sadb_x_policy_dir) { 1522 case IPSEC_DIR_INBOUND: 1523 policy = &in6p->in6p_sp->sp_in; 1524 break; 1525 case IPSEC_DIR_OUTBOUND: 1526 policy = &in6p->in6p_sp->sp_out; 1527 break; 1528 default: 1529 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1530 xpl->sadb_x_policy_dir); 1531 return EINVAL; 1532 } 1533 1534 return ipsec_set_policy(policy, optname, request, len, cred); 1535 } 1536 1537 int 1538 ipsec6_get_policy(struct in6pcb *in6p, const void *request, size_t len, 1539 struct mbuf **mp) 1540 { 1541 const struct sadb_x_policy *xpl; 1542 struct secpolicy *policy; 1543 1544 /* sanity check. */ 1545 if (in6p == NULL || request == NULL || mp == NULL) 1546 return EINVAL; 1547 KASSERT(in6p->in6p_sp != NULL); 1548 if (len < sizeof(*xpl)) 1549 return EINVAL; 1550 xpl = (const struct sadb_x_policy *)request; 1551 1552 /* select direction */ 1553 switch (xpl->sadb_x_policy_dir) { 1554 case IPSEC_DIR_INBOUND: 1555 policy = in6p->in6p_sp->sp_in; 1556 break; 1557 case IPSEC_DIR_OUTBOUND: 1558 policy = in6p->in6p_sp->sp_out; 1559 break; 1560 default: 1561 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1562 xpl->sadb_x_policy_dir); 1563 return EINVAL; 1564 } 1565 1566 return ipsec_get_policy(policy, mp); 1567 } 1568 1569 int 1570 ipsec6_delete_pcbpolicy(struct in6pcb *in6p) 1571 { 1572 1573 KASSERT(in6p != NULL); 1574 1575 if (in6p->in6p_sp == NULL) 1576 return 0; 1577 1578 if (in6p->in6p_sp->sp_in != NULL) 1579 ipsec_destroy_policy(in6p->in6p_sp->sp_in); 1580 1581 if (in6p->in6p_sp->sp_out != NULL) 1582 ipsec_destroy_policy(in6p->in6p_sp->sp_out); 1583 1584 ipsec_invalpcbcache(in6p->in6p_sp, IPSEC_DIR_ANY); 1585 1586 ipsec_delpcbpolicy(in6p->in6p_sp); 1587 in6p->in6p_sp = NULL; 1588 1589 return 0; 1590 } 1591 #endif 1592 1593 /* 1594 * return current level. 1595 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1596 */ 1597 u_int 1598 ipsec_get_reqlevel(const struct ipsecrequest *isr) 1599 { 1600 u_int level = 0; 1601 u_int esp_trans_deflev, esp_net_deflev; 1602 u_int ah_trans_deflev, ah_net_deflev; 1603 1604 KASSERT(isr != NULL); 1605 KASSERT(isr->sp != NULL); 1606 KASSERTMSG( 1607 isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1608 "af family mismatch, src %u, dst %u", 1609 isr->sp->spidx.src.sa.sa_family, isr->sp->spidx.dst.sa.sa_family); 1610 1611 /* XXX note that we have ipseclog() expanded here - code sync issue */ 1612 #define IPSEC_CHECK_DEFAULT(lev) \ 1613 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1614 && (lev) != IPSEC_LEVEL_UNIQUE) ? \ 1615 (ipsec_debug ? log(LOG_INFO, "fixed system default level " #lev \ 1616 ":%d->%d\n", (lev), IPSEC_LEVEL_REQUIRE) : (void)0), \ 1617 (lev) = IPSEC_LEVEL_REQUIRE, (lev) \ 1618 : (lev)) 1619 1620 /* set default level */ 1621 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1622 #ifdef INET 1623 case AF_INET: 1624 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_trans_deflev); 1625 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_net_deflev); 1626 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_trans_deflev); 1627 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_net_deflev); 1628 break; 1629 #endif 1630 #ifdef INET6 1631 case AF_INET6: 1632 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_trans_deflev); 1633 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_net_deflev); 1634 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_trans_deflev); 1635 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_net_deflev); 1636 break; 1637 #endif /* INET6 */ 1638 default: 1639 panic("%s: unknown af %u", __func__, 1640 isr->sp->spidx.src.sa.sa_family); 1641 } 1642 1643 #undef IPSEC_CHECK_DEFAULT 1644 1645 /* set level */ 1646 switch (isr->level) { 1647 case IPSEC_LEVEL_DEFAULT: 1648 switch (isr->saidx.proto) { 1649 case IPPROTO_ESP: 1650 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1651 level = esp_net_deflev; 1652 else 1653 level = esp_trans_deflev; 1654 break; 1655 case IPPROTO_AH: 1656 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1657 level = ah_net_deflev; 1658 else 1659 level = ah_trans_deflev; 1660 break; 1661 case IPPROTO_IPCOMP: 1662 /* 1663 * we don't really care, as IPcomp document says that 1664 * we shouldn't compress small packets 1665 */ 1666 level = IPSEC_LEVEL_USE; 1667 break; 1668 default: 1669 panic("%s: Illegal protocol defined %u", __func__, 1670 isr->saidx.proto); 1671 } 1672 break; 1673 1674 case IPSEC_LEVEL_USE: 1675 case IPSEC_LEVEL_REQUIRE: 1676 level = isr->level; 1677 break; 1678 case IPSEC_LEVEL_UNIQUE: 1679 level = IPSEC_LEVEL_REQUIRE; 1680 break; 1681 1682 default: 1683 panic("%s: Illegal IPsec level %u", __func__, isr->level); 1684 } 1685 1686 return level; 1687 } 1688 1689 /* 1690 * Check security policy requirements against the actual packet contents. 1691 * 1692 * If the SP requires an IPsec packet, and the packet was neither AH nor ESP, 1693 * then kick it. 1694 */ 1695 int 1696 ipsec_in_reject(const struct secpolicy *sp, const struct mbuf *m) 1697 { 1698 struct ipsecrequest *isr; 1699 1700 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1701 printf("%s: using SP\n", __func__); 1702 kdebug_secpolicy(sp); 1703 } 1704 1705 /* check policy */ 1706 switch (sp->policy) { 1707 case IPSEC_POLICY_DISCARD: 1708 return 1; 1709 case IPSEC_POLICY_BYPASS: 1710 case IPSEC_POLICY_NONE: 1711 return 0; 1712 } 1713 1714 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1715 "invalid policy %u", sp->policy); 1716 1717 /* XXX should compare policy against ipsec header history */ 1718 1719 for (isr = sp->req; isr != NULL; isr = isr->next) { 1720 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1721 continue; 1722 switch (isr->saidx.proto) { 1723 case IPPROTO_ESP: 1724 if ((m->m_flags & M_DECRYPTED) == 0) { 1725 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1726 "ESP m_flags:%x\n", m->m_flags); 1727 return 1; 1728 } 1729 break; 1730 case IPPROTO_AH: 1731 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1732 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1733 "AH m_flags:%x\n", m->m_flags); 1734 return 1; 1735 } 1736 break; 1737 case IPPROTO_IPCOMP: 1738 /* 1739 * We don't really care, as IPcomp document 1740 * says that we shouldn't compress small 1741 * packets, IPComp policy should always be 1742 * treated as being in "use" level. 1743 */ 1744 break; 1745 } 1746 } 1747 return 0; /* valid */ 1748 } 1749 1750 /* 1751 * Check AH/ESP integrity. 1752 * This function is called from tcp_input(), udp_input(), 1753 * and {ah,esp}4_input for tunnel mode 1754 */ 1755 int 1756 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1757 { 1758 struct secpolicy *sp; 1759 int error; 1760 int result; 1761 1762 KASSERT(m != NULL); 1763 1764 if (inp == NULL) 1765 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 1766 IP_FORWARDING, &error); 1767 else 1768 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1769 (struct inpcb_hdr *)inp, &error); 1770 1771 if (sp != NULL) { 1772 result = ipsec_in_reject(sp, m); 1773 if (result) 1774 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1775 KEY_SP_UNREF(&sp); 1776 } else { 1777 result = 0; 1778 } 1779 return result; 1780 } 1781 1782 #ifdef INET6 1783 /* 1784 * Check AH/ESP integrity. 1785 * This function is called from tcp6_input(), udp6_input(), 1786 * and {ah,esp}6_input for tunnel mode 1787 */ 1788 int 1789 ipsec6_in_reject(struct mbuf *m, struct in6pcb *in6p) 1790 { 1791 struct secpolicy *sp; 1792 int error; 1793 int result; 1794 1795 KASSERT(m != NULL); 1796 1797 if (in6p == NULL) 1798 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 1799 IP_FORWARDING, &error); 1800 else 1801 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1802 (struct inpcb_hdr *)in6p, &error); 1803 1804 if (sp != NULL) { 1805 result = ipsec_in_reject(sp, m); 1806 if (result) 1807 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1808 KEY_SP_UNREF(&sp); 1809 } else { 1810 result = 0; 1811 } 1812 return result; 1813 } 1814 #endif 1815 1816 /* 1817 * compute the byte size to be occupied by IPsec header. 1818 * in case it is tunneled, it includes the size of outer IP header. 1819 * NOTE: SP passed is free in this function. 1820 */ 1821 static size_t 1822 ipsec_hdrsiz(const struct secpolicy *sp, const struct mbuf *m) 1823 { 1824 struct ipsecrequest *isr; 1825 size_t siz; 1826 1827 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1828 printf("%s: using SP\n", __func__); 1829 kdebug_secpolicy(sp); 1830 } 1831 1832 switch (sp->policy) { 1833 case IPSEC_POLICY_DISCARD: 1834 case IPSEC_POLICY_BYPASS: 1835 case IPSEC_POLICY_NONE: 1836 return 0; 1837 } 1838 1839 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1840 "invalid policy %u", sp->policy); 1841 1842 siz = 0; 1843 for (isr = sp->req; isr != NULL; isr = isr->next) { 1844 size_t clen = 0; 1845 struct secasvar *sav; 1846 1847 switch (isr->saidx.proto) { 1848 case IPPROTO_ESP: 1849 sav = ipsec_lookup_sa(isr, m); 1850 if (sav != NULL) { 1851 clen = esp_hdrsiz(sav); 1852 KEY_SA_UNREF(&sav); 1853 } else 1854 clen = esp_hdrsiz(NULL); 1855 break; 1856 case IPPROTO_AH: 1857 sav = ipsec_lookup_sa(isr, m); 1858 if (sav != NULL) { 1859 clen = ah_hdrsiz(sav); 1860 KEY_SA_UNREF(&sav); 1861 } else 1862 clen = ah_hdrsiz(NULL); 1863 break; 1864 case IPPROTO_IPCOMP: 1865 clen = sizeof(struct ipcomp); 1866 break; 1867 } 1868 1869 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1870 switch (isr->saidx.dst.sa.sa_family) { 1871 case AF_INET: 1872 clen += sizeof(struct ip); 1873 break; 1874 #ifdef INET6 1875 case AF_INET6: 1876 clen += sizeof(struct ip6_hdr); 1877 break; 1878 #endif 1879 default: 1880 IPSECLOG(LOG_ERR, "unknown AF %d in " 1881 "IPsec tunnel SA\n", 1882 ((const struct sockaddr *)&isr->saidx.dst) 1883 ->sa_family); 1884 break; 1885 } 1886 } 1887 siz += clen; 1888 } 1889 1890 return siz; 1891 } 1892 1893 size_t 1894 ipsec4_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1895 { 1896 struct secpolicy *sp; 1897 int error; 1898 size_t size; 1899 1900 KASSERT(m != NULL); 1901 KASSERTMSG(inp == NULL || inp->inp_socket != NULL, "socket w/o inpcb"); 1902 1903 if (inp == NULL) 1904 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1905 else 1906 sp = ipsec_getpolicybysock(m, dir, 1907 (struct inpcb_hdr *)inp, &error); 1908 1909 if (sp != NULL) { 1910 size = ipsec_hdrsiz(sp, m); 1911 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%zu.\n", size); 1912 KEY_SP_UNREF(&sp); 1913 } else { 1914 size = 0; /* XXX should be panic ? */ 1915 } 1916 1917 return size; 1918 } 1919 1920 #ifdef INET6 1921 size_t 1922 ipsec6_hdrsiz(struct mbuf *m, u_int dir, struct in6pcb *in6p) 1923 { 1924 struct secpolicy *sp; 1925 int error; 1926 size_t size; 1927 1928 KASSERT(m != NULL); 1929 KASSERTMSG(in6p == NULL || in6p->in6p_socket != NULL, 1930 "socket w/o inpcb"); 1931 1932 if (in6p == NULL) 1933 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1934 else 1935 sp = ipsec_getpolicybysock(m, dir, 1936 (struct inpcb_hdr *)in6p, &error); 1937 1938 if (sp != NULL) { 1939 size = ipsec_hdrsiz(sp, m); 1940 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%zu.\n", size); 1941 KEY_SP_UNREF(&sp); 1942 } else { 1943 size = 0; 1944 } 1945 1946 return size; 1947 } 1948 #endif 1949 1950 /* 1951 * Check the variable replay window. 1952 * ipsec_chkreplay() performs replay check before ICV verification. 1953 * ipsec_updatereplay() updates replay bitmap. This must be called after 1954 * ICV verification (it also performs replay check, which is usually done 1955 * beforehand). 1956 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1957 * 1958 * based on RFC 2401. 1959 */ 1960 int 1961 ipsec_chkreplay(u_int32_t seq, const struct secasvar *sav) 1962 { 1963 const struct secreplay *replay; 1964 u_int32_t diff; 1965 int fr; 1966 u_int32_t wsizeb; /* constant: bits of window size */ 1967 int frlast; /* constant: last frame */ 1968 1969 IPSEC_SPLASSERT_SOFTNET(__func__); 1970 1971 KASSERT(sav != NULL); 1972 KASSERT(sav->replay != NULL); 1973 1974 replay = sav->replay; 1975 1976 if (replay->wsize == 0) 1977 return 1; /* no need to check replay. */ 1978 1979 /* constant */ 1980 frlast = replay->wsize - 1; 1981 wsizeb = replay->wsize << 3; 1982 1983 /* sequence number of 0 is invalid */ 1984 if (seq == 0) 1985 return 0; 1986 1987 /* first time is always okay */ 1988 if (replay->count == 0) 1989 return 1; 1990 1991 if (seq > replay->lastseq) { 1992 /* larger sequences are okay */ 1993 return 1; 1994 } else { 1995 /* seq is equal or less than lastseq. */ 1996 diff = replay->lastseq - seq; 1997 1998 /* over range to check, i.e. too old or wrapped */ 1999 if (diff >= wsizeb) 2000 return 0; 2001 2002 fr = frlast - diff / 8; 2003 2004 /* this packet already seen ? */ 2005 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2006 return 0; 2007 2008 /* out of order but good */ 2009 return 1; 2010 } 2011 } 2012 2013 /* 2014 * check replay counter whether to update or not. 2015 * OUT: 0: OK 2016 * 1: NG 2017 */ 2018 int 2019 ipsec_updatereplay(u_int32_t seq, const struct secasvar *sav) 2020 { 2021 struct secreplay *replay; 2022 u_int32_t diff; 2023 int fr; 2024 u_int32_t wsizeb; /* constant: bits of window size */ 2025 int frlast; /* constant: last frame */ 2026 2027 IPSEC_SPLASSERT_SOFTNET(__func__); 2028 2029 KASSERT(sav != NULL); 2030 KASSERT(sav->replay != NULL); 2031 2032 replay = sav->replay; 2033 2034 if (replay->wsize == 0) 2035 goto ok; /* no need to check replay. */ 2036 2037 /* constant */ 2038 frlast = replay->wsize - 1; 2039 wsizeb = replay->wsize << 3; 2040 2041 /* sequence number of 0 is invalid */ 2042 if (seq == 0) 2043 return 1; 2044 2045 /* first time */ 2046 if (replay->count == 0) { 2047 replay->lastseq = seq; 2048 memset(replay->bitmap, 0, replay->wsize); 2049 (replay->bitmap)[frlast] = 1; 2050 goto ok; 2051 } 2052 2053 if (seq > replay->lastseq) { 2054 /* seq is larger than lastseq. */ 2055 diff = seq - replay->lastseq; 2056 2057 /* new larger sequence number */ 2058 if (diff < wsizeb) { 2059 /* In window */ 2060 /* set bit for this packet */ 2061 vshiftl(replay->bitmap, diff, replay->wsize); 2062 (replay->bitmap)[frlast] |= 1; 2063 } else { 2064 /* this packet has a "way larger" */ 2065 memset(replay->bitmap, 0, replay->wsize); 2066 (replay->bitmap)[frlast] = 1; 2067 } 2068 replay->lastseq = seq; 2069 2070 /* larger is good */ 2071 } else { 2072 /* seq is equal or less than lastseq. */ 2073 diff = replay->lastseq - seq; 2074 2075 /* over range to check, i.e. too old or wrapped */ 2076 if (diff >= wsizeb) 2077 return 1; 2078 2079 fr = frlast - diff / 8; 2080 2081 /* this packet already seen ? */ 2082 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2083 return 1; 2084 2085 /* mark as seen */ 2086 (replay->bitmap)[fr] |= (1 << (diff % 8)); 2087 2088 /* out of order but good */ 2089 } 2090 2091 ok: 2092 if (replay->count == ~0) { 2093 char buf[IPSEC_LOGSASTRLEN]; 2094 2095 /* set overflow flag */ 2096 replay->overflow++; 2097 2098 /* don't increment, no more packets accepted */ 2099 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 2100 return 1; 2101 2102 IPSECLOG(LOG_WARNING, "replay counter made %d cycle. %s\n", 2103 replay->overflow, ipsec_logsastr(sav, buf, sizeof(buf))); 2104 } 2105 2106 replay->count++; 2107 2108 return 0; 2109 } 2110 2111 /* 2112 * shift variable length bunffer to left. 2113 * IN: bitmap: pointer to the buffer 2114 * nbit: the number of to shift. 2115 * wsize: buffer size (bytes). 2116 */ 2117 static void 2118 vshiftl(unsigned char *bitmap, int nbit, int wsize) 2119 { 2120 int s, j, i; 2121 unsigned char over; 2122 2123 for (j = 0; j < nbit; j += 8) { 2124 s = (nbit - j < 8) ? (nbit - j): 8; 2125 bitmap[0] <<= s; 2126 for (i = 1; i < wsize; i++) { 2127 over = (bitmap[i] >> (8 - s)); 2128 bitmap[i] <<= s; 2129 bitmap[i-1] |= over; 2130 } 2131 } 2132 2133 return; 2134 } 2135 2136 /* Return a printable string for the address. */ 2137 const char * 2138 ipsec_address(const union sockaddr_union *sa, char *buf, size_t size) 2139 { 2140 switch (sa->sa.sa_family) { 2141 #if INET 2142 case AF_INET: 2143 in_print(buf, size, &sa->sin.sin_addr); 2144 return buf; 2145 #endif 2146 2147 #if INET6 2148 case AF_INET6: 2149 in6_print(buf, size, &sa->sin6.sin6_addr); 2150 return buf; 2151 #endif 2152 2153 default: 2154 return "(unknown address family)"; 2155 } 2156 } 2157 2158 const char * 2159 ipsec_logsastr(const struct secasvar *sav, char *buf, size_t size) 2160 { 2161 const struct secasindex *saidx = &sav->sah->saidx; 2162 char sbuf[IPSEC_ADDRSTRLEN], dbuf[IPSEC_ADDRSTRLEN]; 2163 2164 KASSERTMSG(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 2165 "af family mismatch, src %u, dst %u", 2166 saidx->src.sa.sa_family, saidx->dst.sa.sa_family); 2167 2168 snprintf(buf, size, "SA(SPI=%u src=%s dst=%s)", 2169 (u_int32_t)ntohl(sav->spi), 2170 ipsec_address(&saidx->src, sbuf, sizeof(sbuf)), 2171 ipsec_address(&saidx->dst, dbuf, sizeof(dbuf))); 2172 2173 return buf; 2174 } 2175 2176 void 2177 ipsec_dumpmbuf(struct mbuf *m) 2178 { 2179 int totlen; 2180 int i; 2181 u_char *p; 2182 2183 totlen = 0; 2184 printf("---\n"); 2185 while (m) { 2186 p = mtod(m, u_char *); 2187 for (i = 0; i < m->m_len; i++) { 2188 printf("%02x ", p[i]); 2189 totlen++; 2190 if (totlen % 16 == 0) 2191 printf("\n"); 2192 } 2193 m = m->m_next; 2194 } 2195 if (totlen % 16 != 0) 2196 printf("\n"); 2197 printf("---\n"); 2198 } 2199 2200 #ifdef INET6 2201 struct secpolicy * 2202 ipsec6_check_policy(struct mbuf *m, struct in6pcb *in6p, int flags, 2203 int *needipsecp, int *errorp) 2204 { 2205 struct secpolicy *sp = NULL; 2206 int s; 2207 int error = 0; 2208 int needipsec = 0; 2209 2210 if (!ipsec_outdone(m)) { 2211 s = splsoftnet(); 2212 if (in6p != NULL && 2213 ipsec_pcb_skip_ipsec(in6p->in6p_sp, IPSEC_DIR_OUTBOUND)) { 2214 splx(s); 2215 goto skippolicycheck; 2216 } 2217 sp = ipsec6_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error,in6p); 2218 2219 /* 2220 * There are four return cases: 2221 * sp != NULL apply IPsec policy 2222 * sp == NULL, error == 0 no IPsec handling needed 2223 * sp == NULL, error == -EINVAL discard packet w/o error 2224 * sp == NULL, error != 0 discard packet, report error 2225 */ 2226 2227 splx(s); 2228 if (sp == NULL) { 2229 /* 2230 * Caller must check the error return to see if it needs to discard 2231 * the packet. 2232 */ 2233 needipsec = 0; 2234 } else { 2235 needipsec = 1; 2236 } 2237 } 2238 skippolicycheck:; 2239 2240 *errorp = error; 2241 *needipsecp = needipsec; 2242 return sp; 2243 } 2244 2245 int 2246 ipsec6_input(struct mbuf *m) 2247 { 2248 struct secpolicy *sp; 2249 int s, error; 2250 2251 s = splsoftnet(); 2252 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 2253 if (sp != NULL) { 2254 /* 2255 * Check security policy against packet 2256 * attributes. 2257 */ 2258 error = ipsec_in_reject(sp, m); 2259 KEY_SP_UNREF(&sp); 2260 } else { 2261 /* XXX error stat??? */ 2262 error = EINVAL; 2263 IPSECLOG(LOG_DEBUG, "no SP, packet discarded\n");/*XXX*/ 2264 } 2265 splx(s); 2266 2267 return error; 2268 } 2269 #endif /* INET6 */ 2270 2271 2272 2273 /* XXX this stuff doesn't belong here... */ 2274 2275 static struct xformsw *xforms = NULL; 2276 2277 /* 2278 * Register a transform; typically at system startup. 2279 */ 2280 void 2281 xform_register(struct xformsw *xsp) 2282 { 2283 xsp->xf_next = xforms; 2284 xforms = xsp; 2285 } 2286 2287 /* 2288 * Initialize transform support in an sav. 2289 */ 2290 int 2291 xform_init(struct secasvar *sav, int xftype) 2292 { 2293 struct xformsw *xsp; 2294 2295 if (sav->tdb_xform != NULL) /* previously initialized */ 2296 return 0; 2297 for (xsp = xforms; xsp; xsp = xsp->xf_next) 2298 if (xsp->xf_type == xftype) 2299 return (*xsp->xf_init)(sav, xsp); 2300 2301 IPSECLOG(LOG_DEBUG, "no match for xform type %d\n", xftype); 2302 return EINVAL; 2303 } 2304 2305 void 2306 nat_t_ports_get(struct mbuf *m, u_int16_t *dport, u_int16_t *sport) 2307 { 2308 struct m_tag *tag; 2309 2310 if ((tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL))) { 2311 *sport = ((u_int16_t *)(tag + 1))[0]; 2312 *dport = ((u_int16_t *)(tag + 1))[1]; 2313 } else 2314 *sport = *dport = 0; 2315 } 2316 2317 /* 2318 * XXXJRT This should be done as a protosw init call. 2319 */ 2320 void 2321 ipsec_attach(void) 2322 { 2323 2324 ipsec_output_init(); 2325 2326 ipsecstat_percpu = percpu_alloc(sizeof(uint64_t) * IPSEC_NSTATS); 2327 2328 sysctl_net_inet_ipsec_setup(NULL); 2329 #ifdef INET6 2330 sysctl_net_inet6_ipsec6_setup(NULL); 2331 #endif 2332 2333 ah_attach(); 2334 esp_attach(); 2335 ipcomp_attach(); 2336 ipe4_attach(); 2337 #ifdef TCP_SIGNATURE 2338 tcpsignature_attach(); 2339 #endif 2340 } 2341
Indexes created Sun Sep 21 20:09:37 GMT 2025