ipsec.c revision 1.135
1 /* $NetBSD: ipsec.c,v 1.135 2018/02/26 06:17:01 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 1.135 2018/02/26 06:17:01 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 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 578 struct inpcb *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 * ipsec4_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 = ipsec4_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 = ipsec4_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 = ipsec4_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 #ifdef INET6 810 struct secpolicy * 811 ipsec6_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 812 struct in6pcb *in6p) 813 { 814 struct secpolicy *sp; 815 816 *error = 0; 817 818 if (in6p == NULL) { 819 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 820 } else { 821 struct inpcb_hdr *inph = (struct inpcb_hdr *)in6p; 822 KASSERT(inph->inph_socket != NULL); 823 sp = ipsec_getpolicybysock(m, dir, inph, error); 824 } 825 if (sp == NULL) { 826 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 827 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 828 return NULL; 829 } 830 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 831 switch (sp->policy) { 832 case IPSEC_POLICY_ENTRUST: 833 default: 834 printf("%s: invalid policy %u\n", __func__, sp->policy); 835 /* fall thru... */ 836 case IPSEC_POLICY_DISCARD: 837 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 838 *error = -EINVAL; /* packet is discarded by caller */ 839 break; 840 case IPSEC_POLICY_BYPASS: 841 case IPSEC_POLICY_NONE: 842 KEY_SP_UNREF(&sp); 843 sp = NULL; /* NB: force NULL result */ 844 break; 845 case IPSEC_POLICY_IPSEC: 846 KASSERT(sp->req != NULL); 847 break; 848 } 849 if (*error != 0) { 850 KEY_SP_UNREF(&sp); 851 sp = NULL; 852 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 853 } 854 return sp; 855 } 856 #endif /* INET6 */ 857 858 static int 859 ipsec4_setspidx_inpcb(struct mbuf *m, struct inpcb *pcb) 860 { 861 int error; 862 863 KASSERT(pcb != NULL); 864 KASSERT(pcb->inp_sp != NULL); 865 KASSERT(pcb->inp_sp->sp_out != NULL); 866 KASSERT(pcb->inp_sp->sp_in != NULL); 867 868 error = ipsec_setspidx(m, &pcb->inp_sp->sp_in->spidx, 1); 869 if (error == 0) { 870 pcb->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 871 pcb->inp_sp->sp_out->spidx = pcb->inp_sp->sp_in->spidx; 872 pcb->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 873 } else { 874 memset(&pcb->inp_sp->sp_in->spidx, 0, 875 sizeof(pcb->inp_sp->sp_in->spidx)); 876 memset(&pcb->inp_sp->sp_out->spidx, 0, 877 sizeof(pcb->inp_sp->sp_in->spidx)); 878 } 879 return error; 880 } 881 882 #ifdef INET6 883 static int 884 ipsec6_setspidx_in6pcb(struct mbuf *m, struct in6pcb *pcb) 885 { 886 struct secpolicyindex *spidx; 887 int error; 888 889 KASSERT(pcb != NULL); 890 KASSERT(pcb->in6p_sp != NULL); 891 KASSERT(pcb->in6p_sp->sp_out != NULL); 892 KASSERT(pcb->in6p_sp->sp_in != NULL); 893 894 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 895 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 896 897 spidx = &pcb->in6p_sp->sp_in->spidx; 898 error = ipsec_setspidx(m, spidx, 1); 899 if (error) 900 goto bad; 901 spidx->dir = IPSEC_DIR_INBOUND; 902 903 spidx = &pcb->in6p_sp->sp_out->spidx; 904 error = ipsec_setspidx(m, spidx, 1); 905 if (error) 906 goto bad; 907 spidx->dir = IPSEC_DIR_OUTBOUND; 908 909 return 0; 910 911 bad: 912 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 913 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 914 return error; 915 } 916 #endif 917 918 /* 919 * configure security policy index (src/dst/proto/sport/dport) 920 * by looking at the content of mbuf. 921 * the caller is responsible for error recovery (like clearing up spidx). 922 */ 923 static int 924 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 925 { 926 struct ip *ip = NULL; 927 struct ip ipbuf; 928 u_int v; 929 struct mbuf *n; 930 int len; 931 int error; 932 933 KASSERT(m != NULL); 934 935 /* 936 * validate m->m_pkthdr.len. we see incorrect length if we 937 * mistakenly call this function with inconsistent mbuf chain 938 * (like 4.4BSD tcp/udp processing). XXX should we panic here? 939 */ 940 len = 0; 941 for (n = m; n; n = n->m_next) 942 len += n->m_len; 943 if (m->m_pkthdr.len != len) { 944 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 945 "total of m_len(%d) != pkthdr.len(%d), ignored.\n", 946 len, m->m_pkthdr.len); 947 KASSERTMSG(0, "impossible"); 948 return EINVAL; 949 } 950 951 if (m->m_pkthdr.len < sizeof(struct ip)) { 952 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 953 "pkthdr.len(%d) < sizeof(struct ip), ignored.\n", 954 m->m_pkthdr.len); 955 return EINVAL; 956 } 957 958 if (m->m_len >= sizeof(*ip)) { 959 ip = mtod(m, struct ip *); 960 } else { 961 m_copydata(m, 0, sizeof(ipbuf), &ipbuf); 962 ip = &ipbuf; 963 } 964 v = ip->ip_v; 965 switch (v) { 966 case 4: 967 error = ipsec4_setspidx_ipaddr(m, spidx); 968 if (error) 969 return error; 970 ipsec4_get_ulp(m, spidx, needport); 971 return 0; 972 #ifdef INET6 973 case 6: 974 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 975 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 976 "pkthdr.len(%d) < sizeof(struct ip6_hdr), " 977 "ignored.\n", m->m_pkthdr.len); 978 return EINVAL; 979 } 980 error = ipsec6_setspidx_ipaddr(m, spidx); 981 if (error) 982 return error; 983 ipsec6_get_ulp(m, spidx, needport); 984 return 0; 985 #endif 986 default: 987 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 988 "unknown IP version %u, ignored.\n", v); 989 return EINVAL; 990 } 991 } 992 993 static void 994 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 995 { 996 u_int8_t nxt; 997 int off; 998 999 KASSERT(m != NULL); 1000 KASSERTMSG(m->m_pkthdr.len >= sizeof(struct ip), "packet too short"); 1001 1002 /* NB: ip_input() flips it into host endian XXX need more checking */ 1003 if (m->m_len >= sizeof(struct ip)) { 1004 struct ip *ip = mtod(m, struct ip *); 1005 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 1006 goto done; 1007 off = ip->ip_hl << 2; 1008 nxt = ip->ip_p; 1009 } else { 1010 struct ip ih; 1011 1012 m_copydata(m, 0, sizeof(struct ip), &ih); 1013 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 1014 goto done; 1015 off = ih.ip_hl << 2; 1016 nxt = ih.ip_p; 1017 } 1018 1019 while (off < m->m_pkthdr.len) { 1020 struct ip6_ext ip6e; 1021 struct tcphdr th; 1022 struct udphdr uh; 1023 struct icmp icmph; 1024 1025 switch (nxt) { 1026 case IPPROTO_TCP: 1027 spidx->ul_proto = nxt; 1028 if (!needport) 1029 goto done_proto; 1030 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1031 goto done; 1032 m_copydata(m, off, sizeof(th), &th); 1033 spidx->src.sin.sin_port = th.th_sport; 1034 spidx->dst.sin.sin_port = th.th_dport; 1035 return; 1036 case IPPROTO_UDP: 1037 spidx->ul_proto = nxt; 1038 if (!needport) 1039 goto done_proto; 1040 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1041 goto done; 1042 m_copydata(m, off, sizeof(uh), &uh); 1043 spidx->src.sin.sin_port = uh.uh_sport; 1044 spidx->dst.sin.sin_port = uh.uh_dport; 1045 return; 1046 case IPPROTO_AH: 1047 if (off + sizeof(ip6e) > m->m_pkthdr.len) 1048 goto done; 1049 /* XXX sigh, this works but is totally bogus */ 1050 m_copydata(m, off, sizeof(ip6e), &ip6e); 1051 off += (ip6e.ip6e_len + 2) << 2; 1052 nxt = ip6e.ip6e_nxt; 1053 break; 1054 case IPPROTO_ICMP: 1055 spidx->ul_proto = nxt; 1056 if (off + sizeof(struct icmp) > m->m_pkthdr.len) 1057 goto done; 1058 m_copydata(m, off, sizeof(icmph), &icmph); 1059 ((struct sockaddr_in *)&spidx->src)->sin_port = 1060 htons((uint16_t)icmph.icmp_type); 1061 ((struct sockaddr_in *)&spidx->dst)->sin_port = 1062 htons((uint16_t)icmph.icmp_code); 1063 return; 1064 default: 1065 /* XXX intermediate headers??? */ 1066 spidx->ul_proto = nxt; 1067 goto done_proto; 1068 } 1069 } 1070 done: 1071 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1072 done_proto: 1073 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 1074 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 1075 } 1076 1077 static int 1078 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1079 { 1080 static const struct sockaddr_in template = { 1081 sizeof(struct sockaddr_in), 1082 AF_INET, 1083 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 1084 }; 1085 1086 spidx->src.sin = template; 1087 spidx->dst.sin = template; 1088 1089 if (m->m_len < sizeof(struct ip)) { 1090 m_copydata(m, offsetof(struct ip, ip_src), 1091 sizeof(struct in_addr), &spidx->src.sin.sin_addr); 1092 m_copydata(m, offsetof(struct ip, ip_dst), 1093 sizeof(struct in_addr), &spidx->dst.sin.sin_addr); 1094 } else { 1095 struct ip *ip = mtod(m, struct ip *); 1096 spidx->src.sin.sin_addr = ip->ip_src; 1097 spidx->dst.sin.sin_addr = ip->ip_dst; 1098 } 1099 1100 spidx->prefs = sizeof(struct in_addr) << 3; 1101 spidx->prefd = sizeof(struct in_addr) << 3; 1102 1103 return 0; 1104 } 1105 1106 #ifdef INET6 1107 static void 1108 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 1109 { 1110 int off, nxt; 1111 struct tcphdr th; 1112 struct udphdr uh; 1113 struct icmp6_hdr icmph; 1114 1115 KASSERT(m != NULL); 1116 1117 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1118 kdebug_mbuf(__func__, m); 1119 } 1120 1121 /* set default */ 1122 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1123 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 1124 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 1125 1126 nxt = -1; 1127 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 1128 if (off < 0 || m->m_pkthdr.len < off) 1129 return; 1130 1131 switch (nxt) { 1132 case IPPROTO_TCP: 1133 spidx->ul_proto = nxt; 1134 if (!needport) 1135 break; 1136 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1137 break; 1138 m_copydata(m, off, sizeof(th), &th); 1139 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 1140 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 1141 break; 1142 case IPPROTO_UDP: 1143 spidx->ul_proto = nxt; 1144 if (!needport) 1145 break; 1146 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1147 break; 1148 m_copydata(m, off, sizeof(uh), &uh); 1149 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 1150 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 1151 break; 1152 case IPPROTO_ICMPV6: 1153 spidx->ul_proto = nxt; 1154 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 1155 break; 1156 m_copydata(m, off, sizeof(icmph), &icmph); 1157 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 1158 htons((uint16_t)icmph.icmp6_type); 1159 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 1160 htons((uint16_t)icmph.icmp6_code); 1161 break; 1162 default: 1163 /* XXX intermediate headers??? */ 1164 spidx->ul_proto = nxt; 1165 break; 1166 } 1167 } 1168 1169 static int 1170 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1171 { 1172 struct ip6_hdr *ip6 = NULL; 1173 struct ip6_hdr ip6buf; 1174 struct sockaddr_in6 *sin6; 1175 1176 if (m->m_len >= sizeof(*ip6)) 1177 ip6 = mtod(m, struct ip6_hdr *); 1178 else { 1179 m_copydata(m, 0, sizeof(ip6buf), &ip6buf); 1180 ip6 = &ip6buf; 1181 } 1182 1183 sin6 = (struct sockaddr_in6 *)&spidx->src; 1184 memset(sin6, 0, sizeof(*sin6)); 1185 sin6->sin6_family = AF_INET6; 1186 sin6->sin6_len = sizeof(struct sockaddr_in6); 1187 memcpy(&sin6->sin6_addr, &ip6->ip6_src, sizeof(ip6->ip6_src)); 1188 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 1189 sin6->sin6_addr.s6_addr16[1] = 0; 1190 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 1191 } 1192 spidx->prefs = sizeof(struct in6_addr) << 3; 1193 1194 sin6 = (struct sockaddr_in6 *)&spidx->dst; 1195 memset(sin6, 0, sizeof(*sin6)); 1196 sin6->sin6_family = AF_INET6; 1197 sin6->sin6_len = sizeof(struct sockaddr_in6); 1198 memcpy(&sin6->sin6_addr, &ip6->ip6_dst, sizeof(ip6->ip6_dst)); 1199 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 1200 sin6->sin6_addr.s6_addr16[1] = 0; 1201 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 1202 } 1203 spidx->prefd = sizeof(struct in6_addr) << 3; 1204 1205 return 0; 1206 } 1207 #endif 1208 1209 static void 1210 ipsec_delpcbpolicy(struct inpcbpolicy *p) 1211 { 1212 1213 kmem_intr_free(p, sizeof(*p)); 1214 } 1215 1216 /* initialize policy in PCB */ 1217 int 1218 ipsec_init_policy(struct socket *so, struct inpcbpolicy **policy) 1219 { 1220 struct inpcbpolicy *new; 1221 1222 KASSERT(so != NULL); 1223 KASSERT(policy != NULL); 1224 1225 new = kmem_intr_zalloc(sizeof(*new), KM_NOSLEEP); 1226 if (new == NULL) { 1227 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1228 return ENOBUFS; 1229 } 1230 1231 if (IPSEC_PRIVILEGED_SO(so)) 1232 new->priv = 1; 1233 else 1234 new->priv = 0; 1235 1236 /* 1237 * Set dummy SPs. Actual SPs will be allocated later if needed. 1238 */ 1239 new->sp_in = &ipsec_dummy_sp; 1240 new->sp_out = &ipsec_dummy_sp; 1241 1242 *policy = new; 1243 1244 return 0; 1245 } 1246 1247 #if 0 /* unused */ 1248 /* copy old ipsec policy into new */ 1249 int 1250 ipsec_copy_policy(const struct inpcbpolicy *old, struct inpcbpolicy *new) 1251 { 1252 struct secpolicy *sp; 1253 1254 sp = ipsec_deepcopy_policy(old->sp_in); 1255 if (sp) { 1256 KEY_SP_UNREF(&new->sp_in); 1257 new->sp_in = sp; 1258 } else 1259 return ENOBUFS; 1260 1261 sp = ipsec_deepcopy_policy(old->sp_out); 1262 if (sp) { 1263 KEY_SP_UNREF(&new->sp_out); 1264 new->sp_out = sp; 1265 } else 1266 return ENOBUFS; 1267 1268 new->priv = old->priv; 1269 1270 return 0; 1271 } 1272 1273 /* deep-copy a policy in PCB */ 1274 static struct secpolicy * 1275 ipsec_deepcopy_policy(const struct secpolicy *src) 1276 { 1277 struct ipsecrequest *newchain = NULL; 1278 const struct ipsecrequest *p; 1279 struct ipsecrequest **q; 1280 struct secpolicy *dst; 1281 1282 if (src == NULL) 1283 return NULL; 1284 dst = KEY_NEWSP(); 1285 if (dst == NULL) 1286 return NULL; 1287 1288 /* 1289 * deep-copy IPsec request chain. This is required since struct 1290 * ipsecrequest is not reference counted. 1291 */ 1292 q = &newchain; 1293 for (p = src->req; p; p = p->next) { 1294 *q = kmem_zalloc(sizeof(**q), KM_SLEEP); 1295 (*q)->next = NULL; 1296 1297 (*q)->saidx.proto = p->saidx.proto; 1298 (*q)->saidx.mode = p->saidx.mode; 1299 (*q)->level = p->level; 1300 (*q)->saidx.reqid = p->saidx.reqid; 1301 1302 memcpy(&(*q)->saidx.src, &p->saidx.src, sizeof((*q)->saidx.src)); 1303 memcpy(&(*q)->saidx.dst, &p->saidx.dst, sizeof((*q)->saidx.dst)); 1304 1305 (*q)->sp = dst; 1306 1307 q = &((*q)->next); 1308 } 1309 1310 dst->req = newchain; 1311 dst->state = src->state; 1312 dst->policy = src->policy; 1313 /* do not touch the refcnt fields */ 1314 1315 return dst; 1316 } 1317 #endif 1318 1319 static void 1320 ipsec_destroy_policy(struct secpolicy *sp) 1321 { 1322 1323 if (sp == &ipsec_dummy_sp) 1324 ; /* It's dummy. No need to free it. */ 1325 else { 1326 /* 1327 * We cannot destroy here because it can be called in 1328 * softint. So mark the SP as DEAD and let the timer 1329 * destroy it. See key_timehandler_spd. 1330 */ 1331 sp->state = IPSEC_SPSTATE_DEAD; 1332 } 1333 } 1334 1335 /* set policy and ipsec request if present. */ 1336 static int 1337 ipsec_set_policy(struct secpolicy **policy, int optname, const void *request, 1338 size_t len, kauth_cred_t cred) 1339 { 1340 const struct sadb_x_policy *xpl; 1341 struct secpolicy *newsp = NULL, *oldsp; 1342 int error; 1343 1344 KASSERT(!cpu_softintr_p()); 1345 1346 /* sanity check. */ 1347 if (policy == NULL || *policy == NULL || request == NULL) 1348 return EINVAL; 1349 if (len < sizeof(*xpl)) 1350 return EINVAL; 1351 xpl = (const struct sadb_x_policy *)request; 1352 1353 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1354 kdebug_sadb_xpolicy("set passed policy", request); 1355 } 1356 1357 /* check policy type */ 1358 /* ipsec_set_policy() accepts IPSEC, ENTRUST and BYPASS. */ 1359 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD || 1360 xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1361 return EINVAL; 1362 1363 /* check privileged socket */ 1364 if (xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1365 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPSEC, 1366 KAUTH_REQ_NETWORK_IPSEC_BYPASS, NULL, NULL, NULL); 1367 if (error) 1368 return error; 1369 } 1370 1371 /* allocation new SP entry */ 1372 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1373 return error; 1374 1375 key_init_sp(newsp); 1376 newsp->created = time_uptime; 1377 /* Insert the global list for SPs for sockets */ 1378 key_socksplist_add(newsp); 1379 1380 /* clear old SP and set new SP */ 1381 oldsp = *policy; 1382 *policy = newsp; 1383 ipsec_destroy_policy(oldsp); 1384 1385 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1386 printf("%s: new policy\n", __func__); 1387 kdebug_secpolicy(newsp); 1388 } 1389 1390 return 0; 1391 } 1392 1393 static int 1394 ipsec_get_policy(struct secpolicy *policy, struct mbuf **mp) 1395 { 1396 1397 /* sanity check. */ 1398 if (policy == NULL || mp == NULL) 1399 return EINVAL; 1400 1401 *mp = key_sp2msg(policy, M_NOWAIT); 1402 if (!*mp) { 1403 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1404 return ENOBUFS; 1405 } 1406 1407 (*mp)->m_type = MT_DATA; 1408 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1409 kdebug_mbuf(__func__, *mp); 1410 } 1411 1412 return 0; 1413 } 1414 1415 int 1416 ipsec4_set_policy(struct inpcb *inp, int optname, const void *request, 1417 size_t len, kauth_cred_t cred) 1418 { 1419 const struct sadb_x_policy *xpl; 1420 struct secpolicy **policy; 1421 1422 KASSERT(!cpu_softintr_p()); 1423 KASSERT(inp != NULL); 1424 KASSERT(inp_locked(inp)); 1425 KASSERT(request != NULL); 1426 1427 if (len < sizeof(*xpl)) 1428 return EINVAL; 1429 xpl = (const struct sadb_x_policy *)request; 1430 1431 KASSERT(inp->inp_sp != NULL); 1432 1433 /* select direction */ 1434 switch (xpl->sadb_x_policy_dir) { 1435 case IPSEC_DIR_INBOUND: 1436 policy = &inp->inp_sp->sp_in; 1437 break; 1438 case IPSEC_DIR_OUTBOUND: 1439 policy = &inp->inp_sp->sp_out; 1440 break; 1441 default: 1442 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1443 xpl->sadb_x_policy_dir); 1444 return EINVAL; 1445 } 1446 1447 return ipsec_set_policy(policy, optname, request, len, cred); 1448 } 1449 1450 int 1451 ipsec4_get_policy(struct inpcb *inp, const void *request, size_t len, 1452 struct mbuf **mp) 1453 { 1454 const struct sadb_x_policy *xpl; 1455 struct secpolicy *policy; 1456 1457 /* sanity check. */ 1458 if (inp == NULL || request == NULL || mp == NULL) 1459 return EINVAL; 1460 KASSERT(inp->inp_sp != NULL); 1461 if (len < sizeof(*xpl)) 1462 return EINVAL; 1463 xpl = (const struct sadb_x_policy *)request; 1464 1465 /* select direction */ 1466 switch (xpl->sadb_x_policy_dir) { 1467 case IPSEC_DIR_INBOUND: 1468 policy = inp->inp_sp->sp_in; 1469 break; 1470 case IPSEC_DIR_OUTBOUND: 1471 policy = inp->inp_sp->sp_out; 1472 break; 1473 default: 1474 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1475 xpl->sadb_x_policy_dir); 1476 return EINVAL; 1477 } 1478 1479 return ipsec_get_policy(policy, mp); 1480 } 1481 1482 int 1483 ipsec4_delete_pcbpolicy(struct inpcb *inp) 1484 { 1485 1486 KASSERT(inp != NULL); 1487 1488 if (inp->inp_sp == NULL) 1489 return 0; 1490 1491 if (inp->inp_sp->sp_in != NULL) 1492 ipsec_destroy_policy(inp->inp_sp->sp_in); 1493 1494 if (inp->inp_sp->sp_out != NULL) 1495 ipsec_destroy_policy(inp->inp_sp->sp_out); 1496 1497 ipsec_invalpcbcache(inp->inp_sp, IPSEC_DIR_ANY); 1498 1499 ipsec_delpcbpolicy(inp->inp_sp); 1500 inp->inp_sp = NULL; 1501 1502 return 0; 1503 } 1504 1505 #ifdef INET6 1506 int 1507 ipsec6_set_policy(struct in6pcb *in6p, int optname, const void *request, 1508 size_t len, kauth_cred_t cred) 1509 { 1510 const struct sadb_x_policy *xpl; 1511 struct secpolicy **policy; 1512 1513 KASSERT(!cpu_softintr_p()); 1514 KASSERT(in6p_locked(in6p)); 1515 1516 /* sanity check. */ 1517 if (in6p == NULL || request == NULL) 1518 return EINVAL; 1519 if (len < sizeof(*xpl)) 1520 return EINVAL; 1521 xpl = (const struct sadb_x_policy *)request; 1522 1523 /* select direction */ 1524 switch (xpl->sadb_x_policy_dir) { 1525 case IPSEC_DIR_INBOUND: 1526 policy = &in6p->in6p_sp->sp_in; 1527 break; 1528 case IPSEC_DIR_OUTBOUND: 1529 policy = &in6p->in6p_sp->sp_out; 1530 break; 1531 default: 1532 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1533 xpl->sadb_x_policy_dir); 1534 return EINVAL; 1535 } 1536 1537 return ipsec_set_policy(policy, optname, request, len, cred); 1538 } 1539 1540 int 1541 ipsec6_get_policy(struct in6pcb *in6p, const void *request, size_t len, 1542 struct mbuf **mp) 1543 { 1544 const struct sadb_x_policy *xpl; 1545 struct secpolicy *policy; 1546 1547 /* sanity check. */ 1548 if (in6p == NULL || request == NULL || mp == NULL) 1549 return EINVAL; 1550 KASSERT(in6p->in6p_sp != NULL); 1551 if (len < sizeof(*xpl)) 1552 return EINVAL; 1553 xpl = (const struct sadb_x_policy *)request; 1554 1555 /* select direction */ 1556 switch (xpl->sadb_x_policy_dir) { 1557 case IPSEC_DIR_INBOUND: 1558 policy = in6p->in6p_sp->sp_in; 1559 break; 1560 case IPSEC_DIR_OUTBOUND: 1561 policy = in6p->in6p_sp->sp_out; 1562 break; 1563 default: 1564 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1565 xpl->sadb_x_policy_dir); 1566 return EINVAL; 1567 } 1568 1569 return ipsec_get_policy(policy, mp); 1570 } 1571 1572 int 1573 ipsec6_delete_pcbpolicy(struct in6pcb *in6p) 1574 { 1575 1576 KASSERT(in6p != NULL); 1577 1578 if (in6p->in6p_sp == NULL) 1579 return 0; 1580 1581 if (in6p->in6p_sp->sp_in != NULL) 1582 ipsec_destroy_policy(in6p->in6p_sp->sp_in); 1583 1584 if (in6p->in6p_sp->sp_out != NULL) 1585 ipsec_destroy_policy(in6p->in6p_sp->sp_out); 1586 1587 ipsec_invalpcbcache(in6p->in6p_sp, IPSEC_DIR_ANY); 1588 1589 ipsec_delpcbpolicy(in6p->in6p_sp); 1590 in6p->in6p_sp = NULL; 1591 1592 return 0; 1593 } 1594 #endif 1595 1596 /* 1597 * Return the current level (either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE). 1598 */ 1599 u_int 1600 ipsec_get_reqlevel(const struct ipsecrequest *isr) 1601 { 1602 u_int level = 0; 1603 u_int esp_trans_deflev, esp_net_deflev; 1604 u_int ah_trans_deflev, ah_net_deflev; 1605 1606 KASSERT(isr != NULL); 1607 KASSERT(isr->sp != NULL); 1608 KASSERTMSG( 1609 isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1610 "af family mismatch, src %u, dst %u", 1611 isr->sp->spidx.src.sa.sa_family, isr->sp->spidx.dst.sa.sa_family); 1612 1613 /* XXX note that we have ipseclog() expanded here - code sync issue */ 1614 #define IPSEC_CHECK_DEFAULT(lev) \ 1615 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1616 && (lev) != IPSEC_LEVEL_UNIQUE) ? \ 1617 (ipsec_debug ? log(LOG_INFO, "fixed system default level " #lev \ 1618 ":%d->%d\n", (lev), IPSEC_LEVEL_REQUIRE) : (void)0), \ 1619 (lev) = IPSEC_LEVEL_REQUIRE, (lev) \ 1620 : (lev)) 1621 1622 /* set default level */ 1623 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1624 #ifdef INET 1625 case AF_INET: 1626 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_trans_deflev); 1627 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_net_deflev); 1628 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_trans_deflev); 1629 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_net_deflev); 1630 break; 1631 #endif 1632 #ifdef INET6 1633 case AF_INET6: 1634 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_trans_deflev); 1635 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_net_deflev); 1636 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_trans_deflev); 1637 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_net_deflev); 1638 break; 1639 #endif /* INET6 */ 1640 default: 1641 panic("%s: unknown af %u", __func__, 1642 isr->sp->spidx.src.sa.sa_family); 1643 } 1644 1645 #undef IPSEC_CHECK_DEFAULT 1646 1647 /* set level */ 1648 switch (isr->level) { 1649 case IPSEC_LEVEL_DEFAULT: 1650 switch (isr->saidx.proto) { 1651 case IPPROTO_ESP: 1652 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1653 level = esp_net_deflev; 1654 else 1655 level = esp_trans_deflev; 1656 break; 1657 case IPPROTO_AH: 1658 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1659 level = ah_net_deflev; 1660 else 1661 level = ah_trans_deflev; 1662 break; 1663 case IPPROTO_IPCOMP: 1664 /* 1665 * we don't really care, as IPcomp document says that 1666 * we shouldn't compress small packets 1667 */ 1668 level = IPSEC_LEVEL_USE; 1669 break; 1670 default: 1671 panic("%s: Illegal protocol defined %u", __func__, 1672 isr->saidx.proto); 1673 } 1674 break; 1675 1676 case IPSEC_LEVEL_USE: 1677 case IPSEC_LEVEL_REQUIRE: 1678 level = isr->level; 1679 break; 1680 case IPSEC_LEVEL_UNIQUE: 1681 level = IPSEC_LEVEL_REQUIRE; 1682 break; 1683 1684 default: 1685 panic("%s: Illegal IPsec level %u", __func__, isr->level); 1686 } 1687 1688 return level; 1689 } 1690 1691 /* 1692 * Check security policy requirements against the actual packet contents. 1693 * 1694 * If the SP requires an IPsec packet, and the packet was neither AH nor ESP, 1695 * then kick it. 1696 */ 1697 int 1698 ipsec_sp_reject(const struct secpolicy *sp, const struct mbuf *m) 1699 { 1700 struct ipsecrequest *isr; 1701 1702 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1703 printf("%s: using SP\n", __func__); 1704 kdebug_secpolicy(sp); 1705 } 1706 1707 /* check policy */ 1708 switch (sp->policy) { 1709 case IPSEC_POLICY_DISCARD: 1710 return 1; 1711 case IPSEC_POLICY_BYPASS: 1712 case IPSEC_POLICY_NONE: 1713 return 0; 1714 } 1715 1716 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1717 "invalid policy %u", sp->policy); 1718 1719 /* XXX should compare policy against ipsec header history */ 1720 1721 for (isr = sp->req; isr != NULL; isr = isr->next) { 1722 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1723 continue; 1724 switch (isr->saidx.proto) { 1725 case IPPROTO_ESP: 1726 if ((m->m_flags & M_DECRYPTED) == 0) { 1727 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1728 "ESP m_flags:%x\n", m->m_flags); 1729 return 1; 1730 } 1731 break; 1732 case IPPROTO_AH: 1733 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1734 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1735 "AH m_flags:%x\n", m->m_flags); 1736 return 1; 1737 } 1738 break; 1739 case IPPROTO_IPCOMP: 1740 /* 1741 * We don't really care, as IPcomp document 1742 * says that we shouldn't compress small 1743 * packets, IPComp policy should always be 1744 * treated as being in "use" level. 1745 */ 1746 break; 1747 } 1748 } 1749 1750 return 0; 1751 } 1752 1753 /* 1754 * Check AH/ESP integrity. 1755 * This function is called from tcp_input(), udp_input(), 1756 * and {ah,esp}4_input for tunnel mode 1757 */ 1758 int 1759 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1760 { 1761 struct inpcb_hdr *inph = (struct inpcb_hdr *)inp; 1762 struct secpolicy *sp; 1763 int error; 1764 int result; 1765 1766 KASSERT(m != NULL); 1767 1768 if (inph == NULL) 1769 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 1770 IP_FORWARDING, &error); 1771 else 1772 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1773 inph, &error); 1774 1775 if (sp != NULL) { 1776 result = ipsec_sp_reject(sp, m); 1777 if (result) 1778 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1779 KEY_SP_UNREF(&sp); 1780 } else { 1781 result = 0; 1782 } 1783 return result; 1784 } 1785 1786 #ifdef INET6 1787 /* 1788 * Check AH/ESP integrity. 1789 * This function is called from tcp6_input(), udp6_input(), 1790 * and {ah,esp}6_input for tunnel mode 1791 */ 1792 int 1793 ipsec6_in_reject(struct mbuf *m, struct in6pcb *in6p) 1794 { 1795 struct inpcb_hdr *inph = (struct inpcb_hdr *)in6p; 1796 struct secpolicy *sp; 1797 int error; 1798 int result; 1799 1800 KASSERT(m != NULL); 1801 1802 if (inph == NULL) 1803 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 1804 IP_FORWARDING, &error); 1805 else 1806 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1807 inph, &error); 1808 1809 if (sp != NULL) { 1810 result = ipsec_sp_reject(sp, m); 1811 if (result) 1812 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1813 KEY_SP_UNREF(&sp); 1814 } else { 1815 result = 0; 1816 } 1817 return result; 1818 } 1819 #endif 1820 1821 /* 1822 * Compute the byte size to be occupied by the IPsec header. If it is 1823 * tunneled, it includes the size of outer IP header. 1824 */ 1825 static size_t 1826 ipsec_sp_hdrsiz(const struct secpolicy *sp, const struct mbuf *m) 1827 { 1828 struct ipsecrequest *isr; 1829 size_t siz; 1830 1831 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1832 printf("%s: using SP\n", __func__); 1833 kdebug_secpolicy(sp); 1834 } 1835 1836 switch (sp->policy) { 1837 case IPSEC_POLICY_DISCARD: 1838 case IPSEC_POLICY_BYPASS: 1839 case IPSEC_POLICY_NONE: 1840 return 0; 1841 } 1842 1843 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1844 "invalid policy %u", sp->policy); 1845 1846 siz = 0; 1847 for (isr = sp->req; isr != NULL; isr = isr->next) { 1848 size_t clen = 0; 1849 struct secasvar *sav; 1850 1851 switch (isr->saidx.proto) { 1852 case IPPROTO_ESP: 1853 sav = ipsec_lookup_sa(isr, m); 1854 if (sav != NULL) { 1855 clen = esp_hdrsiz(sav); 1856 KEY_SA_UNREF(&sav); 1857 } else 1858 clen = esp_hdrsiz(NULL); 1859 break; 1860 case IPPROTO_AH: 1861 sav = ipsec_lookup_sa(isr, m); 1862 if (sav != NULL) { 1863 clen = ah_hdrsiz(sav); 1864 KEY_SA_UNREF(&sav); 1865 } else 1866 clen = ah_hdrsiz(NULL); 1867 break; 1868 case IPPROTO_IPCOMP: 1869 clen = sizeof(struct ipcomp); 1870 break; 1871 } 1872 1873 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1874 switch (isr->saidx.dst.sa.sa_family) { 1875 case AF_INET: 1876 clen += sizeof(struct ip); 1877 break; 1878 #ifdef INET6 1879 case AF_INET6: 1880 clen += sizeof(struct ip6_hdr); 1881 break; 1882 #endif 1883 default: 1884 IPSECLOG(LOG_ERR, "unknown AF %d in " 1885 "IPsec tunnel SA\n", 1886 ((const struct sockaddr *)&isr->saidx.dst) 1887 ->sa_family); 1888 break; 1889 } 1890 } 1891 siz += clen; 1892 } 1893 1894 return siz; 1895 } 1896 1897 size_t 1898 ipsec4_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1899 { 1900 struct inpcb_hdr *inph = (struct inpcb_hdr *)inp; 1901 struct secpolicy *sp; 1902 int error; 1903 size_t size; 1904 1905 KASSERT(m != NULL); 1906 KASSERTMSG(inph == NULL || inph->inph_socket != NULL, 1907 "socket w/o inpcb"); 1908 1909 if (inph == NULL) 1910 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1911 else 1912 sp = ipsec_getpolicybysock(m, dir, inph, &error); 1913 1914 if (sp != NULL) { 1915 size = ipsec_sp_hdrsiz(sp, m); 1916 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%zu.\n", size); 1917 KEY_SP_UNREF(&sp); 1918 } else { 1919 size = 0; 1920 } 1921 1922 return size; 1923 } 1924 1925 #ifdef INET6 1926 size_t 1927 ipsec6_hdrsiz(struct mbuf *m, u_int dir, struct in6pcb *in6p) 1928 { 1929 struct inpcb_hdr *inph = (struct inpcb_hdr *)in6p; 1930 struct secpolicy *sp; 1931 int error; 1932 size_t size; 1933 1934 KASSERT(m != NULL); 1935 KASSERTMSG(inph == NULL || inph->inph_socket != NULL, 1936 "socket w/o inpcb"); 1937 1938 if (inph == NULL) 1939 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1940 else 1941 sp = ipsec_getpolicybysock(m, dir, inph, &error); 1942 1943 if (sp != NULL) { 1944 size = ipsec_sp_hdrsiz(sp, m); 1945 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%zu.\n", size); 1946 KEY_SP_UNREF(&sp); 1947 } else { 1948 size = 0; 1949 } 1950 1951 return size; 1952 } 1953 #endif 1954 1955 /* 1956 * Check the variable replay window. 1957 * ipsec_chkreplay() performs replay check before ICV verification. 1958 * ipsec_updatereplay() updates replay bitmap. This must be called after 1959 * ICV verification (it also performs replay check, which is usually done 1960 * beforehand). 1961 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1962 * 1963 * based on RFC 2401. 1964 */ 1965 int 1966 ipsec_chkreplay(u_int32_t seq, const struct secasvar *sav) 1967 { 1968 const struct secreplay *replay; 1969 u_int32_t diff; 1970 int fr; 1971 u_int32_t wsizeb; /* constant: bits of window size */ 1972 int frlast; /* constant: last frame */ 1973 1974 IPSEC_SPLASSERT_SOFTNET(__func__); 1975 1976 KASSERT(sav != NULL); 1977 KASSERT(sav->replay != NULL); 1978 1979 replay = sav->replay; 1980 1981 if (replay->wsize == 0) 1982 return 1; /* no need to check replay. */ 1983 1984 /* constant */ 1985 frlast = replay->wsize - 1; 1986 wsizeb = replay->wsize << 3; 1987 1988 /* sequence number of 0 is invalid */ 1989 if (seq == 0) 1990 return 0; 1991 1992 /* first time is always okay */ 1993 if (replay->count == 0) 1994 return 1; 1995 1996 if (seq > replay->lastseq) { 1997 /* larger sequences are okay */ 1998 return 1; 1999 } else { 2000 /* seq is equal or less than lastseq. */ 2001 diff = replay->lastseq - seq; 2002 2003 /* over range to check, i.e. too old or wrapped */ 2004 if (diff >= wsizeb) 2005 return 0; 2006 2007 fr = frlast - diff / 8; 2008 2009 /* this packet already seen ? */ 2010 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2011 return 0; 2012 2013 /* out of order but good */ 2014 return 1; 2015 } 2016 } 2017 2018 /* 2019 * check replay counter whether to update or not. 2020 * OUT: 0: OK 2021 * 1: NG 2022 */ 2023 int 2024 ipsec_updatereplay(u_int32_t seq, const struct secasvar *sav) 2025 { 2026 struct secreplay *replay; 2027 u_int32_t diff; 2028 int fr; 2029 u_int32_t wsizeb; /* constant: bits of window size */ 2030 int frlast; /* constant: last frame */ 2031 2032 IPSEC_SPLASSERT_SOFTNET(__func__); 2033 2034 KASSERT(sav != NULL); 2035 KASSERT(sav->replay != NULL); 2036 2037 replay = sav->replay; 2038 2039 if (replay->wsize == 0) 2040 goto ok; /* no need to check replay. */ 2041 2042 /* constant */ 2043 frlast = replay->wsize - 1; 2044 wsizeb = replay->wsize << 3; 2045 2046 /* sequence number of 0 is invalid */ 2047 if (seq == 0) 2048 return 1; 2049 2050 /* first time */ 2051 if (replay->count == 0) { 2052 replay->lastseq = seq; 2053 memset(replay->bitmap, 0, replay->wsize); 2054 (replay->bitmap)[frlast] = 1; 2055 goto ok; 2056 } 2057 2058 if (seq > replay->lastseq) { 2059 /* seq is larger than lastseq. */ 2060 diff = seq - replay->lastseq; 2061 2062 /* new larger sequence number */ 2063 if (diff < wsizeb) { 2064 /* In window */ 2065 /* set bit for this packet */ 2066 vshiftl(replay->bitmap, diff, replay->wsize); 2067 (replay->bitmap)[frlast] |= 1; 2068 } else { 2069 /* this packet has a "way larger" */ 2070 memset(replay->bitmap, 0, replay->wsize); 2071 (replay->bitmap)[frlast] = 1; 2072 } 2073 replay->lastseq = seq; 2074 2075 /* larger is good */ 2076 } else { 2077 /* seq is equal or less than lastseq. */ 2078 diff = replay->lastseq - seq; 2079 2080 /* over range to check, i.e. too old or wrapped */ 2081 if (diff >= wsizeb) 2082 return 1; 2083 2084 fr = frlast - diff / 8; 2085 2086 /* this packet already seen ? */ 2087 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2088 return 1; 2089 2090 /* mark as seen */ 2091 (replay->bitmap)[fr] |= (1 << (diff % 8)); 2092 2093 /* out of order but good */ 2094 } 2095 2096 ok: 2097 if (replay->count == ~0) { 2098 char buf[IPSEC_LOGSASTRLEN]; 2099 2100 /* set overflow flag */ 2101 replay->overflow++; 2102 2103 /* don't increment, no more packets accepted */ 2104 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 2105 return 1; 2106 2107 IPSECLOG(LOG_WARNING, "replay counter made %d cycle. %s\n", 2108 replay->overflow, ipsec_logsastr(sav, buf, sizeof(buf))); 2109 } 2110 2111 replay->count++; 2112 2113 return 0; 2114 } 2115 2116 /* 2117 * shift variable length buffer to left. 2118 * IN: bitmap: pointer to the buffer 2119 * nbit: the number of to shift. 2120 * wsize: buffer size (bytes). 2121 */ 2122 static void 2123 vshiftl(unsigned char *bitmap, int nbit, int wsize) 2124 { 2125 int s, j, i; 2126 unsigned char over; 2127 2128 for (j = 0; j < nbit; j += 8) { 2129 s = (nbit - j < 8) ? (nbit - j): 8; 2130 bitmap[0] <<= s; 2131 for (i = 1; i < wsize; i++) { 2132 over = (bitmap[i] >> (8 - s)); 2133 bitmap[i] <<= s; 2134 bitmap[i-1] |= over; 2135 } 2136 } 2137 2138 return; 2139 } 2140 2141 /* Return a printable string for the address. */ 2142 const char * 2143 ipsec_address(const union sockaddr_union *sa, char *buf, size_t size) 2144 { 2145 switch (sa->sa.sa_family) { 2146 #if INET 2147 case AF_INET: 2148 in_print(buf, size, &sa->sin.sin_addr); 2149 return buf; 2150 #endif 2151 #if INET6 2152 case AF_INET6: 2153 in6_print(buf, size, &sa->sin6.sin6_addr); 2154 return buf; 2155 #endif 2156 default: 2157 return "(unknown address family)"; 2158 } 2159 } 2160 2161 const char * 2162 ipsec_logsastr(const struct secasvar *sav, char *buf, size_t size) 2163 { 2164 const struct secasindex *saidx = &sav->sah->saidx; 2165 char sbuf[IPSEC_ADDRSTRLEN], dbuf[IPSEC_ADDRSTRLEN]; 2166 2167 KASSERTMSG(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 2168 "af family mismatch, src %u, dst %u", 2169 saidx->src.sa.sa_family, saidx->dst.sa.sa_family); 2170 2171 snprintf(buf, size, "SA(SPI=%u src=%s dst=%s)", 2172 (u_int32_t)ntohl(sav->spi), 2173 ipsec_address(&saidx->src, sbuf, sizeof(sbuf)), 2174 ipsec_address(&saidx->dst, dbuf, sizeof(dbuf))); 2175 2176 return buf; 2177 } 2178 2179 void 2180 ipsec_dumpmbuf(struct mbuf *m) 2181 { 2182 int totlen; 2183 int i; 2184 u_char *p; 2185 2186 totlen = 0; 2187 printf("---\n"); 2188 while (m) { 2189 p = mtod(m, u_char *); 2190 for (i = 0; i < m->m_len; i++) { 2191 printf("%02x ", p[i]); 2192 totlen++; 2193 if (totlen % 16 == 0) 2194 printf("\n"); 2195 } 2196 m = m->m_next; 2197 } 2198 if (totlen % 16 != 0) 2199 printf("\n"); 2200 printf("---\n"); 2201 } 2202 2203 #ifdef INET6 2204 struct secpolicy * 2205 ipsec6_check_policy(struct mbuf *m, struct in6pcb *in6p, int flags, 2206 int *needipsecp, int *errorp) 2207 { 2208 struct secpolicy *sp = NULL; 2209 int s; 2210 int error = 0; 2211 int needipsec = 0; 2212 2213 if (!ipsec_outdone(m)) { 2214 s = splsoftnet(); 2215 if (in6p != NULL && 2216 ipsec_pcb_skip_ipsec(in6p->in6p_sp, IPSEC_DIR_OUTBOUND)) { 2217 splx(s); 2218 goto skippolicycheck; 2219 } 2220 sp = ipsec6_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, 2221 in6p); 2222 2223 /* 2224 * There are four return cases: 2225 * sp != NULL apply IPsec policy 2226 * sp == NULL, error == 0 no IPsec handling needed 2227 * sp == NULL, error == -EINVAL discard packet w/o error 2228 * sp == NULL, error != 0 discard packet, report error 2229 */ 2230 2231 splx(s); 2232 if (sp == NULL) { 2233 /* 2234 * Caller must check the error return to see if it needs to discard 2235 * the packet. 2236 */ 2237 needipsec = 0; 2238 } else { 2239 needipsec = 1; 2240 } 2241 } 2242 skippolicycheck:; 2243 2244 *errorp = error; 2245 *needipsecp = needipsec; 2246 return sp; 2247 } 2248 2249 int 2250 ipsec6_input(struct mbuf *m) 2251 { 2252 struct secpolicy *sp; 2253 int s, error; 2254 2255 s = splsoftnet(); 2256 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 2257 if (sp != NULL) { 2258 /* 2259 * Check security policy against packet 2260 * attributes. 2261 */ 2262 error = ipsec_sp_reject(sp, m); 2263 KEY_SP_UNREF(&sp); 2264 } else { 2265 /* XXX error stat??? */ 2266 error = EINVAL; 2267 IPSECLOG(LOG_DEBUG, "no SP, packet discarded\n");/*XXX*/ 2268 } 2269 splx(s); 2270 2271 return error; 2272 } 2273 #endif /* INET6 */ 2274 2275 /* 2276 * ----------------------------------------------------------------------------- 2277 */ 2278 2279 /* XXX this stuff doesn't belong here... */ 2280 2281 static struct xformsw *xforms = NULL; 2282 2283 /* 2284 * Register a transform; typically at system startup. 2285 */ 2286 void 2287 xform_register(struct xformsw *xsp) 2288 { 2289 xsp->xf_next = xforms; 2290 xforms = xsp; 2291 } 2292 2293 /* 2294 * Initialize transform support in an sav. 2295 */ 2296 int 2297 xform_init(struct secasvar *sav, int xftype) 2298 { 2299 struct xformsw *xsp; 2300 2301 if (sav->tdb_xform != NULL) /* previously initialized */ 2302 return 0; 2303 for (xsp = xforms; xsp; xsp = xsp->xf_next) 2304 if (xsp->xf_type == xftype) 2305 return (*xsp->xf_init)(sav, xsp); 2306 2307 IPSECLOG(LOG_DEBUG, "no match for xform type %d\n", xftype); 2308 return EINVAL; 2309 } 2310 2311 void 2312 nat_t_ports_get(struct mbuf *m, u_int16_t *dport, u_int16_t *sport) 2313 { 2314 struct m_tag *tag; 2315 2316 if ((tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL))) { 2317 *sport = ((u_int16_t *)(tag + 1))[0]; 2318 *dport = ((u_int16_t *)(tag + 1))[1]; 2319 } else 2320 *sport = *dport = 0; 2321 } 2322 2323 /* 2324 * XXXJRT This should be done as a protosw init call. 2325 */ 2326 void 2327 ipsec_attach(void) 2328 { 2329 2330 ipsec_output_init(); 2331 2332 ipsecstat_percpu = percpu_alloc(sizeof(uint64_t) * IPSEC_NSTATS); 2333 2334 sysctl_net_inet_ipsec_setup(NULL); 2335 #ifdef INET6 2336 sysctl_net_inet6_ipsec6_setup(NULL); 2337 #endif 2338 2339 ah_attach(); 2340 esp_attach(); 2341 ipcomp_attach(); 2342 ipe4_attach(); 2343 #ifdef TCP_SIGNATURE 2344 tcpsignature_attach(); 2345 #endif 2346 } 2347
Indexes created Mon Sep 22 13:09:51 GMT 2025