ipsec.c revision 1.134
1 /* $NetBSD: ipsec.c,v 1.134 2018/02/21 16:42:33 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 1.134 2018/02/21 16:42:33 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 switch (sp->policy) { 598 case IPSEC_POLICY_ENTRUST: 599 default: 600 printf("%s: invalid policy %u\n", __func__, sp->policy); 601 /* fall thru... */ 602 case IPSEC_POLICY_DISCARD: 603 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 604 *error = -EINVAL; /* packet is discarded by caller */ 605 break; 606 case IPSEC_POLICY_BYPASS: 607 case IPSEC_POLICY_NONE: 608 KEY_SP_UNREF(&sp); 609 sp = NULL; /* NB: force NULL result */ 610 break; 611 case IPSEC_POLICY_IPSEC: 612 KASSERT(sp->req != NULL); 613 break; 614 } 615 if (*error != 0) { 616 KEY_SP_UNREF(&sp); 617 sp = NULL; 618 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 619 } 620 return sp; 621 } 622 623 int 624 ipsec4_output(struct mbuf *m, struct inpcb *inp, int flags, 625 u_long *mtu, bool *natt_frag, bool *done) 626 { 627 struct secpolicy *sp = NULL; 628 int error, s; 629 630 /* 631 * Check the security policy (SP) for the packet and, if required, 632 * do IPsec-related processing. There are two cases here; the first 633 * time a packet is sent through it will be untagged and handled by 634 * ipsec4_checkpolicy(). If the packet is resubmitted to ip_output 635 * (e.g. after AH, ESP, etc. processing), there will be a tag to 636 * bypass the lookup and related policy checking. 637 */ 638 if (ipsec_outdone(m)) { 639 return 0; 640 } 641 s = splsoftnet(); 642 if (inp && ipsec_pcb_skip_ipsec(inp->inp_sp, IPSEC_DIR_OUTBOUND)) { 643 splx(s); 644 return 0; 645 } 646 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, inp); 647 648 /* 649 * There are four return cases: 650 * sp != NULL apply IPsec policy 651 * sp == NULL, error == 0 no IPsec handling needed 652 * sp == NULL, error == -EINVAL discard packet w/o error 653 * sp == NULL, error != 0 discard packet, report error 654 */ 655 if (sp == NULL) { 656 splx(s); 657 if (error) { 658 /* 659 * Hack: -EINVAL is used to signal that a packet 660 * should be silently discarded. This is typically 661 * because we asked key management for an SA and 662 * it was delayed (e.g. kicked up to IKE). 663 */ 664 if (error == -EINVAL) 665 error = 0; 666 m_freem(m); 667 *done = true; 668 return error; 669 } 670 /* No IPsec processing for this packet. */ 671 return 0; 672 } 673 674 /* 675 * Do delayed checksums now because we send before 676 * this is done in the normal processing path. 677 */ 678 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 679 in_delayed_cksum(m); 680 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 681 } 682 683 { 684 u_long _mtu = 0; 685 686 error = ipsec4_process_packet(m, sp->req, &_mtu); 687 688 if (error == 0 && _mtu != 0) { 689 /* 690 * NAT-T ESP fragmentation: do not do IPSec processing 691 * now, we will do it on each fragmented packet. 692 */ 693 *mtu = _mtu; 694 *natt_frag = true; 695 KEY_SP_UNREF(&sp); 696 splx(s); 697 return 0; 698 } 699 } 700 /* 701 * Preserve KAME behaviour: ENOENT can be returned 702 * when an SA acquire is in progress. Don't propagate 703 * this to user-level; it confuses applications. 704 * 705 * XXX this will go away when the SADB is redone. 706 */ 707 if (error == ENOENT) 708 error = 0; 709 KEY_SP_UNREF(&sp); 710 splx(s); 711 *done = true; 712 return error; 713 } 714 715 int 716 ipsec4_input(struct mbuf *m, int flags) 717 { 718 struct secpolicy *sp; 719 int error, s; 720 721 s = splsoftnet(); 722 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 723 if (sp == NULL) { 724 splx(s); 725 return EINVAL; 726 } 727 728 /* 729 * Check security policy against packet attributes. 730 */ 731 error = ipsec_sp_reject(sp, m); 732 KEY_SP_UNREF(&sp); 733 splx(s); 734 if (error) { 735 return error; 736 } 737 738 if (flags == 0) { 739 /* We are done. */ 740 return 0; 741 } 742 743 /* 744 * Peek at the outbound SP for this packet to determine if 745 * it is a Fast Forward candidate. 746 */ 747 s = splsoftnet(); 748 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, NULL); 749 if (sp != NULL) { 750 m->m_flags &= ~M_CANFASTFWD; 751 KEY_SP_UNREF(&sp); 752 } 753 splx(s); 754 return 0; 755 } 756 757 int 758 ipsec4_forward(struct mbuf *m, int *destmtu) 759 { 760 /* 761 * If the packet is routed over IPsec tunnel, tell the 762 * originator the tunnel MTU. 763 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 764 * XXX quickhack!!! 765 */ 766 struct secpolicy *sp; 767 size_t ipsechdr; 768 int error; 769 770 sp = ipsec_getpolicybyaddr(m, 771 IPSEC_DIR_OUTBOUND, IP_FORWARDING, &error); 772 if (sp == NULL) { 773 return EINVAL; 774 } 775 776 /* Count IPsec header size. */ 777 ipsechdr = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, NULL); 778 779 /* 780 * Find the correct route for outer IPv4 header, compute tunnel MTU. 781 */ 782 if (sp->req) { 783 struct secasvar *sav; 784 785 sav = ipsec_lookup_sa(sp->req, m); 786 if (sav != NULL) { 787 struct route *ro; 788 struct rtentry *rt; 789 790 ro = &sav->sah->sa_route; 791 rt = rtcache_validate(ro); 792 if (rt && rt->rt_ifp) { 793 *destmtu = rt->rt_rmx.rmx_mtu ? 794 rt->rt_rmx.rmx_mtu : rt->rt_ifp->if_mtu; 795 *destmtu -= ipsechdr; 796 } 797 rtcache_unref(rt, ro); 798 KEY_SA_UNREF(&sav); 799 } 800 } 801 KEY_SP_UNREF(&sp); 802 return 0; 803 } 804 805 #ifdef INET6 806 struct secpolicy * 807 ipsec6_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 808 struct in6pcb *in6p) 809 { 810 struct secpolicy *sp; 811 812 *error = 0; 813 814 if (in6p == NULL) { 815 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 816 } else { 817 struct inpcb_hdr *inph = (struct inpcb_hdr *)in6p; 818 KASSERT(inph->inph_socket != NULL); 819 sp = ipsec_getpolicybysock(m, dir, inph, error); 820 } 821 if (sp == NULL) { 822 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 823 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 824 return NULL; 825 } 826 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 827 switch (sp->policy) { 828 case IPSEC_POLICY_ENTRUST: 829 default: 830 printf("%s: invalid policy %u\n", __func__, sp->policy); 831 /* fall thru... */ 832 case IPSEC_POLICY_DISCARD: 833 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 834 *error = -EINVAL; /* packet is discarded by caller */ 835 break; 836 case IPSEC_POLICY_BYPASS: 837 case IPSEC_POLICY_NONE: 838 KEY_SP_UNREF(&sp); 839 sp = NULL; /* NB: force NULL result */ 840 break; 841 case IPSEC_POLICY_IPSEC: 842 KASSERT(sp->req != NULL); 843 break; 844 } 845 if (*error != 0) { 846 KEY_SP_UNREF(&sp); 847 sp = NULL; 848 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 849 } 850 return sp; 851 } 852 #endif /* INET6 */ 853 854 static int 855 ipsec4_setspidx_inpcb(struct mbuf *m, struct inpcb *pcb) 856 { 857 int error; 858 859 KASSERT(pcb != NULL); 860 KASSERT(pcb->inp_sp != NULL); 861 KASSERT(pcb->inp_sp->sp_out != NULL); 862 KASSERT(pcb->inp_sp->sp_in != NULL); 863 864 error = ipsec_setspidx(m, &pcb->inp_sp->sp_in->spidx, 1); 865 if (error == 0) { 866 pcb->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 867 pcb->inp_sp->sp_out->spidx = pcb->inp_sp->sp_in->spidx; 868 pcb->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 869 } else { 870 memset(&pcb->inp_sp->sp_in->spidx, 0, 871 sizeof(pcb->inp_sp->sp_in->spidx)); 872 memset(&pcb->inp_sp->sp_out->spidx, 0, 873 sizeof(pcb->inp_sp->sp_in->spidx)); 874 } 875 return error; 876 } 877 878 #ifdef INET6 879 static int 880 ipsec6_setspidx_in6pcb(struct mbuf *m, struct in6pcb *pcb) 881 { 882 struct secpolicyindex *spidx; 883 int error; 884 885 KASSERT(pcb != NULL); 886 KASSERT(pcb->in6p_sp != NULL); 887 KASSERT(pcb->in6p_sp->sp_out != NULL); 888 KASSERT(pcb->in6p_sp->sp_in != NULL); 889 890 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 891 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 892 893 spidx = &pcb->in6p_sp->sp_in->spidx; 894 error = ipsec_setspidx(m, spidx, 1); 895 if (error) 896 goto bad; 897 spidx->dir = IPSEC_DIR_INBOUND; 898 899 spidx = &pcb->in6p_sp->sp_out->spidx; 900 error = ipsec_setspidx(m, spidx, 1); 901 if (error) 902 goto bad; 903 spidx->dir = IPSEC_DIR_OUTBOUND; 904 905 return 0; 906 907 bad: 908 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 909 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 910 return error; 911 } 912 #endif 913 914 /* 915 * configure security policy index (src/dst/proto/sport/dport) 916 * by looking at the content of mbuf. 917 * the caller is responsible for error recovery (like clearing up spidx). 918 */ 919 static int 920 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 921 { 922 struct ip *ip = NULL; 923 struct ip ipbuf; 924 u_int v; 925 struct mbuf *n; 926 int len; 927 int error; 928 929 KASSERT(m != NULL); 930 931 /* 932 * validate m->m_pkthdr.len. we see incorrect length if we 933 * mistakenly call this function with inconsistent mbuf chain 934 * (like 4.4BSD tcp/udp processing). XXX should we panic here? 935 */ 936 len = 0; 937 for (n = m; n; n = n->m_next) 938 len += n->m_len; 939 if (m->m_pkthdr.len != len) { 940 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 941 "total of m_len(%d) != pkthdr.len(%d), ignored.\n", 942 len, m->m_pkthdr.len); 943 return EINVAL; 944 } 945 946 if (m->m_pkthdr.len < sizeof(struct ip)) { 947 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 948 "pkthdr.len(%d) < sizeof(struct ip), ignored.\n", 949 m->m_pkthdr.len); 950 return EINVAL; 951 } 952 953 if (m->m_len >= sizeof(*ip)) { 954 ip = mtod(m, struct ip *); 955 } else { 956 m_copydata(m, 0, sizeof(ipbuf), &ipbuf); 957 ip = &ipbuf; 958 } 959 v = ip->ip_v; 960 switch (v) { 961 case 4: 962 error = ipsec4_setspidx_ipaddr(m, spidx); 963 if (error) 964 return error; 965 ipsec4_get_ulp(m, spidx, needport); 966 return 0; 967 #ifdef INET6 968 case 6: 969 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 970 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 971 "pkthdr.len(%d) < sizeof(struct ip6_hdr), " 972 "ignored.\n", m->m_pkthdr.len); 973 return EINVAL; 974 } 975 error = ipsec6_setspidx_ipaddr(m, spidx); 976 if (error) 977 return error; 978 ipsec6_get_ulp(m, spidx, needport); 979 return 0; 980 #endif 981 default: 982 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 983 "unknown IP version %u, ignored.\n", v); 984 return EINVAL; 985 } 986 } 987 988 static void 989 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 990 { 991 u_int8_t nxt; 992 int off; 993 994 KASSERT(m != NULL); 995 KASSERTMSG(m->m_pkthdr.len >= sizeof(struct ip), "packet too short"); 996 997 /* NB: ip_input() flips it into host endian XXX need more checking */ 998 if (m->m_len >= sizeof(struct ip)) { 999 struct ip *ip = mtod(m, struct ip *); 1000 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 1001 goto done; 1002 off = ip->ip_hl << 2; 1003 nxt = ip->ip_p; 1004 } else { 1005 struct ip ih; 1006 1007 m_copydata(m, 0, sizeof(struct ip), &ih); 1008 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 1009 goto done; 1010 off = ih.ip_hl << 2; 1011 nxt = ih.ip_p; 1012 } 1013 1014 while (off < m->m_pkthdr.len) { 1015 struct ip6_ext ip6e; 1016 struct tcphdr th; 1017 struct udphdr uh; 1018 struct icmp icmph; 1019 1020 switch (nxt) { 1021 case IPPROTO_TCP: 1022 spidx->ul_proto = nxt; 1023 if (!needport) 1024 goto done_proto; 1025 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1026 goto done; 1027 m_copydata(m, off, sizeof(th), &th); 1028 spidx->src.sin.sin_port = th.th_sport; 1029 spidx->dst.sin.sin_port = th.th_dport; 1030 return; 1031 case IPPROTO_UDP: 1032 spidx->ul_proto = nxt; 1033 if (!needport) 1034 goto done_proto; 1035 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1036 goto done; 1037 m_copydata(m, off, sizeof(uh), &uh); 1038 spidx->src.sin.sin_port = uh.uh_sport; 1039 spidx->dst.sin.sin_port = uh.uh_dport; 1040 return; 1041 case IPPROTO_AH: 1042 if (off + sizeof(ip6e) > m->m_pkthdr.len) 1043 goto done; 1044 /* XXX sigh, this works but is totally bogus */ 1045 m_copydata(m, off, sizeof(ip6e), &ip6e); 1046 off += (ip6e.ip6e_len + 2) << 2; 1047 nxt = ip6e.ip6e_nxt; 1048 break; 1049 case IPPROTO_ICMP: 1050 spidx->ul_proto = nxt; 1051 if (off + sizeof(struct icmp) > m->m_pkthdr.len) 1052 goto done; 1053 m_copydata(m, off, sizeof(icmph), &icmph); 1054 ((struct sockaddr_in *)&spidx->src)->sin_port = 1055 htons((uint16_t)icmph.icmp_type); 1056 ((struct sockaddr_in *)&spidx->dst)->sin_port = 1057 htons((uint16_t)icmph.icmp_code); 1058 return; 1059 default: 1060 /* XXX intermediate headers??? */ 1061 spidx->ul_proto = nxt; 1062 goto done_proto; 1063 } 1064 } 1065 done: 1066 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1067 done_proto: 1068 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 1069 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 1070 } 1071 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 static int 1165 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1166 { 1167 struct ip6_hdr *ip6 = NULL; 1168 struct ip6_hdr ip6buf; 1169 struct sockaddr_in6 *sin6; 1170 1171 if (m->m_len >= sizeof(*ip6)) 1172 ip6 = mtod(m, struct ip6_hdr *); 1173 else { 1174 m_copydata(m, 0, sizeof(ip6buf), &ip6buf); 1175 ip6 = &ip6buf; 1176 } 1177 1178 sin6 = (struct sockaddr_in6 *)&spidx->src; 1179 memset(sin6, 0, sizeof(*sin6)); 1180 sin6->sin6_family = AF_INET6; 1181 sin6->sin6_len = sizeof(struct sockaddr_in6); 1182 memcpy(&sin6->sin6_addr, &ip6->ip6_src, sizeof(ip6->ip6_src)); 1183 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 1184 sin6->sin6_addr.s6_addr16[1] = 0; 1185 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 1186 } 1187 spidx->prefs = sizeof(struct in6_addr) << 3; 1188 1189 sin6 = (struct sockaddr_in6 *)&spidx->dst; 1190 memset(sin6, 0, sizeof(*sin6)); 1191 sin6->sin6_family = AF_INET6; 1192 sin6->sin6_len = sizeof(struct sockaddr_in6); 1193 memcpy(&sin6->sin6_addr, &ip6->ip6_dst, sizeof(ip6->ip6_dst)); 1194 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 1195 sin6->sin6_addr.s6_addr16[1] = 0; 1196 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 1197 } 1198 spidx->prefd = sizeof(struct in6_addr) << 3; 1199 1200 return 0; 1201 } 1202 #endif 1203 1204 static void 1205 ipsec_delpcbpolicy(struct inpcbpolicy *p) 1206 { 1207 1208 kmem_intr_free(p, sizeof(*p)); 1209 } 1210 1211 /* initialize policy in PCB */ 1212 int 1213 ipsec_init_policy(struct socket *so, struct inpcbpolicy **policy) 1214 { 1215 struct inpcbpolicy *new; 1216 1217 KASSERT(so != NULL); 1218 KASSERT(policy != NULL); 1219 1220 new = kmem_intr_zalloc(sizeof(*new), KM_NOSLEEP); 1221 if (new == NULL) { 1222 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1223 return ENOBUFS; 1224 } 1225 1226 if (IPSEC_PRIVILEGED_SO(so)) 1227 new->priv = 1; 1228 else 1229 new->priv = 0; 1230 1231 /* 1232 * Set dummy SPs. Actual SPs will be allocated later if needed. 1233 */ 1234 new->sp_in = &ipsec_dummy_sp; 1235 new->sp_out = &ipsec_dummy_sp; 1236 1237 *policy = new; 1238 1239 return 0; 1240 } 1241 1242 #if 0 /* unused */ 1243 /* copy old ipsec policy into new */ 1244 int 1245 ipsec_copy_policy(const struct inpcbpolicy *old, struct inpcbpolicy *new) 1246 { 1247 struct secpolicy *sp; 1248 1249 sp = ipsec_deepcopy_policy(old->sp_in); 1250 if (sp) { 1251 KEY_SP_UNREF(&new->sp_in); 1252 new->sp_in = sp; 1253 } else 1254 return ENOBUFS; 1255 1256 sp = ipsec_deepcopy_policy(old->sp_out); 1257 if (sp) { 1258 KEY_SP_UNREF(&new->sp_out); 1259 new->sp_out = sp; 1260 } else 1261 return ENOBUFS; 1262 1263 new->priv = old->priv; 1264 1265 return 0; 1266 } 1267 1268 /* deep-copy a policy in PCB */ 1269 static struct secpolicy * 1270 ipsec_deepcopy_policy(const struct secpolicy *src) 1271 { 1272 struct ipsecrequest *newchain = NULL; 1273 const struct ipsecrequest *p; 1274 struct ipsecrequest **q; 1275 struct secpolicy *dst; 1276 1277 if (src == NULL) 1278 return NULL; 1279 dst = KEY_NEWSP(); 1280 if (dst == NULL) 1281 return NULL; 1282 1283 /* 1284 * deep-copy IPsec request chain. This is required since struct 1285 * ipsecrequest is not reference counted. 1286 */ 1287 q = &newchain; 1288 for (p = src->req; p; p = p->next) { 1289 *q = kmem_zalloc(sizeof(**q), KM_SLEEP); 1290 (*q)->next = NULL; 1291 1292 (*q)->saidx.proto = p->saidx.proto; 1293 (*q)->saidx.mode = p->saidx.mode; 1294 (*q)->level = p->level; 1295 (*q)->saidx.reqid = p->saidx.reqid; 1296 1297 memcpy(&(*q)->saidx.src, &p->saidx.src, sizeof((*q)->saidx.src)); 1298 memcpy(&(*q)->saidx.dst, &p->saidx.dst, sizeof((*q)->saidx.dst)); 1299 1300 (*q)->sp = dst; 1301 1302 q = &((*q)->next); 1303 } 1304 1305 dst->req = newchain; 1306 dst->state = src->state; 1307 dst->policy = src->policy; 1308 /* do not touch the refcnt fields */ 1309 1310 return dst; 1311 } 1312 #endif 1313 1314 static void 1315 ipsec_destroy_policy(struct secpolicy *sp) 1316 { 1317 1318 if (sp == &ipsec_dummy_sp) 1319 ; /* It's dummy. No need to free it. */ 1320 else { 1321 /* 1322 * We cannot destroy here because it can be called in 1323 * softint. So mark the SP as DEAD and let the timer 1324 * destroy it. See key_timehandler_spd. 1325 */ 1326 sp->state = IPSEC_SPSTATE_DEAD; 1327 } 1328 } 1329 1330 /* set policy and ipsec request if present. */ 1331 static int 1332 ipsec_set_policy(struct secpolicy **policy, int optname, const void *request, 1333 size_t len, kauth_cred_t cred) 1334 { 1335 const struct sadb_x_policy *xpl; 1336 struct secpolicy *newsp = NULL, *oldsp; 1337 int error; 1338 1339 KASSERT(!cpu_softintr_p()); 1340 1341 /* sanity check. */ 1342 if (policy == NULL || *policy == NULL || request == NULL) 1343 return EINVAL; 1344 if (len < sizeof(*xpl)) 1345 return EINVAL; 1346 xpl = (const struct sadb_x_policy *)request; 1347 1348 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1349 kdebug_sadb_xpolicy("set passed policy", request); 1350 } 1351 1352 /* check policy type */ 1353 /* ipsec_set_policy() accepts IPSEC, ENTRUST and BYPASS. */ 1354 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD || 1355 xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1356 return EINVAL; 1357 1358 /* check privileged socket */ 1359 if (xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1360 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPSEC, 1361 KAUTH_REQ_NETWORK_IPSEC_BYPASS, NULL, NULL, NULL); 1362 if (error) 1363 return error; 1364 } 1365 1366 /* allocation new SP entry */ 1367 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1368 return error; 1369 1370 key_init_sp(newsp); 1371 newsp->created = time_uptime; 1372 /* Insert the global list for SPs for sockets */ 1373 key_socksplist_add(newsp); 1374 1375 /* clear old SP and set new SP */ 1376 oldsp = *policy; 1377 *policy = newsp; 1378 ipsec_destroy_policy(oldsp); 1379 1380 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1381 printf("%s: new policy\n", __func__); 1382 kdebug_secpolicy(newsp); 1383 } 1384 1385 return 0; 1386 } 1387 1388 static int 1389 ipsec_get_policy(struct secpolicy *policy, struct mbuf **mp) 1390 { 1391 1392 /* sanity check. */ 1393 if (policy == NULL || mp == NULL) 1394 return EINVAL; 1395 1396 *mp = key_sp2msg(policy, M_NOWAIT); 1397 if (!*mp) { 1398 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1399 return ENOBUFS; 1400 } 1401 1402 (*mp)->m_type = MT_DATA; 1403 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1404 kdebug_mbuf(__func__, *mp); 1405 } 1406 1407 return 0; 1408 } 1409 1410 int 1411 ipsec4_set_policy(struct inpcb *inp, int optname, const void *request, 1412 size_t len, kauth_cred_t cred) 1413 { 1414 const struct sadb_x_policy *xpl; 1415 struct secpolicy **policy; 1416 1417 KASSERT(!cpu_softintr_p()); 1418 KASSERT(inp != NULL); 1419 KASSERT(inp_locked(inp)); 1420 KASSERT(request != NULL); 1421 1422 if (len < sizeof(*xpl)) 1423 return EINVAL; 1424 xpl = (const struct sadb_x_policy *)request; 1425 1426 KASSERT(inp->inp_sp != NULL); 1427 1428 /* select direction */ 1429 switch (xpl->sadb_x_policy_dir) { 1430 case IPSEC_DIR_INBOUND: 1431 policy = &inp->inp_sp->sp_in; 1432 break; 1433 case IPSEC_DIR_OUTBOUND: 1434 policy = &inp->inp_sp->sp_out; 1435 break; 1436 default: 1437 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1438 xpl->sadb_x_policy_dir); 1439 return EINVAL; 1440 } 1441 1442 return ipsec_set_policy(policy, optname, request, len, cred); 1443 } 1444 1445 int 1446 ipsec4_get_policy(struct inpcb *inp, const void *request, size_t len, 1447 struct mbuf **mp) 1448 { 1449 const struct sadb_x_policy *xpl; 1450 struct secpolicy *policy; 1451 1452 /* sanity check. */ 1453 if (inp == NULL || request == NULL || mp == NULL) 1454 return EINVAL; 1455 KASSERT(inp->inp_sp != NULL); 1456 if (len < sizeof(*xpl)) 1457 return EINVAL; 1458 xpl = (const struct sadb_x_policy *)request; 1459 1460 /* select direction */ 1461 switch (xpl->sadb_x_policy_dir) { 1462 case IPSEC_DIR_INBOUND: 1463 policy = inp->inp_sp->sp_in; 1464 break; 1465 case IPSEC_DIR_OUTBOUND: 1466 policy = inp->inp_sp->sp_out; 1467 break; 1468 default: 1469 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1470 xpl->sadb_x_policy_dir); 1471 return EINVAL; 1472 } 1473 1474 return ipsec_get_policy(policy, mp); 1475 } 1476 1477 /* delete policy in PCB */ 1478 int 1479 ipsec4_delete_pcbpolicy(struct inpcb *inp) 1480 { 1481 1482 KASSERT(inp != NULL); 1483 1484 if (inp->inp_sp == NULL) 1485 return 0; 1486 1487 if (inp->inp_sp->sp_in != NULL) 1488 ipsec_destroy_policy(inp->inp_sp->sp_in); 1489 1490 if (inp->inp_sp->sp_out != NULL) 1491 ipsec_destroy_policy(inp->inp_sp->sp_out); 1492 1493 ipsec_invalpcbcache(inp->inp_sp, IPSEC_DIR_ANY); 1494 1495 ipsec_delpcbpolicy(inp->inp_sp); 1496 inp->inp_sp = NULL; 1497 1498 return 0; 1499 } 1500 1501 #ifdef INET6 1502 int 1503 ipsec6_set_policy(struct in6pcb *in6p, int optname, const void *request, 1504 size_t len, kauth_cred_t cred) 1505 { 1506 const struct sadb_x_policy *xpl; 1507 struct secpolicy **policy; 1508 1509 KASSERT(!cpu_softintr_p()); 1510 KASSERT(in6p_locked(in6p)); 1511 1512 /* sanity check. */ 1513 if (in6p == NULL || request == NULL) 1514 return EINVAL; 1515 if (len < sizeof(*xpl)) 1516 return EINVAL; 1517 xpl = (const struct sadb_x_policy *)request; 1518 1519 /* select direction */ 1520 switch (xpl->sadb_x_policy_dir) { 1521 case IPSEC_DIR_INBOUND: 1522 policy = &in6p->in6p_sp->sp_in; 1523 break; 1524 case IPSEC_DIR_OUTBOUND: 1525 policy = &in6p->in6p_sp->sp_out; 1526 break; 1527 default: 1528 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1529 xpl->sadb_x_policy_dir); 1530 return EINVAL; 1531 } 1532 1533 return ipsec_set_policy(policy, optname, request, len, cred); 1534 } 1535 1536 int 1537 ipsec6_get_policy(struct in6pcb *in6p, const void *request, size_t len, 1538 struct mbuf **mp) 1539 { 1540 const struct sadb_x_policy *xpl; 1541 struct secpolicy *policy; 1542 1543 /* sanity check. */ 1544 if (in6p == NULL || request == NULL || mp == NULL) 1545 return EINVAL; 1546 KASSERT(in6p->in6p_sp != NULL); 1547 if (len < sizeof(*xpl)) 1548 return EINVAL; 1549 xpl = (const struct sadb_x_policy *)request; 1550 1551 /* select direction */ 1552 switch (xpl->sadb_x_policy_dir) { 1553 case IPSEC_DIR_INBOUND: 1554 policy = in6p->in6p_sp->sp_in; 1555 break; 1556 case IPSEC_DIR_OUTBOUND: 1557 policy = in6p->in6p_sp->sp_out; 1558 break; 1559 default: 1560 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1561 xpl->sadb_x_policy_dir); 1562 return EINVAL; 1563 } 1564 1565 return ipsec_get_policy(policy, mp); 1566 } 1567 1568 int 1569 ipsec6_delete_pcbpolicy(struct in6pcb *in6p) 1570 { 1571 1572 KASSERT(in6p != NULL); 1573 1574 if (in6p->in6p_sp == NULL) 1575 return 0; 1576 1577 if (in6p->in6p_sp->sp_in != NULL) 1578 ipsec_destroy_policy(in6p->in6p_sp->sp_in); 1579 1580 if (in6p->in6p_sp->sp_out != NULL) 1581 ipsec_destroy_policy(in6p->in6p_sp->sp_out); 1582 1583 ipsec_invalpcbcache(in6p->in6p_sp, IPSEC_DIR_ANY); 1584 1585 ipsec_delpcbpolicy(in6p->in6p_sp); 1586 in6p->in6p_sp = NULL; 1587 1588 return 0; 1589 } 1590 #endif 1591 1592 /* 1593 * return current level. 1594 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1595 */ 1596 u_int 1597 ipsec_get_reqlevel(const struct ipsecrequest *isr) 1598 { 1599 u_int level = 0; 1600 u_int esp_trans_deflev, esp_net_deflev; 1601 u_int ah_trans_deflev, ah_net_deflev; 1602 1603 KASSERT(isr != NULL); 1604 KASSERT(isr->sp != NULL); 1605 KASSERTMSG( 1606 isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1607 "af family mismatch, src %u, dst %u", 1608 isr->sp->spidx.src.sa.sa_family, isr->sp->spidx.dst.sa.sa_family); 1609 1610 /* XXX note that we have ipseclog() expanded here - code sync issue */ 1611 #define IPSEC_CHECK_DEFAULT(lev) \ 1612 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1613 && (lev) != IPSEC_LEVEL_UNIQUE) ? \ 1614 (ipsec_debug ? log(LOG_INFO, "fixed system default level " #lev \ 1615 ":%d->%d\n", (lev), IPSEC_LEVEL_REQUIRE) : (void)0), \ 1616 (lev) = IPSEC_LEVEL_REQUIRE, (lev) \ 1617 : (lev)) 1618 1619 /* set default level */ 1620 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1621 #ifdef INET 1622 case AF_INET: 1623 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_trans_deflev); 1624 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_net_deflev); 1625 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_trans_deflev); 1626 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_net_deflev); 1627 break; 1628 #endif 1629 #ifdef INET6 1630 case AF_INET6: 1631 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_trans_deflev); 1632 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_net_deflev); 1633 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_trans_deflev); 1634 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_net_deflev); 1635 break; 1636 #endif /* INET6 */ 1637 default: 1638 panic("%s: unknown af %u", __func__, 1639 isr->sp->spidx.src.sa.sa_family); 1640 } 1641 1642 #undef IPSEC_CHECK_DEFAULT 1643 1644 /* set level */ 1645 switch (isr->level) { 1646 case IPSEC_LEVEL_DEFAULT: 1647 switch (isr->saidx.proto) { 1648 case IPPROTO_ESP: 1649 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1650 level = esp_net_deflev; 1651 else 1652 level = esp_trans_deflev; 1653 break; 1654 case IPPROTO_AH: 1655 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1656 level = ah_net_deflev; 1657 else 1658 level = ah_trans_deflev; 1659 break; 1660 case IPPROTO_IPCOMP: 1661 /* 1662 * we don't really care, as IPcomp document says that 1663 * we shouldn't compress small packets 1664 */ 1665 level = IPSEC_LEVEL_USE; 1666 break; 1667 default: 1668 panic("%s: Illegal protocol defined %u", __func__, 1669 isr->saidx.proto); 1670 } 1671 break; 1672 1673 case IPSEC_LEVEL_USE: 1674 case IPSEC_LEVEL_REQUIRE: 1675 level = isr->level; 1676 break; 1677 case IPSEC_LEVEL_UNIQUE: 1678 level = IPSEC_LEVEL_REQUIRE; 1679 break; 1680 1681 default: 1682 panic("%s: Illegal IPsec level %u", __func__, isr->level); 1683 } 1684 1685 return level; 1686 } 1687 1688 /* 1689 * Check security policy requirements against the actual packet contents. 1690 * 1691 * If the SP requires an IPsec packet, and the packet was neither AH nor ESP, 1692 * then kick it. 1693 */ 1694 int 1695 ipsec_sp_reject(const struct secpolicy *sp, const struct mbuf *m) 1696 { 1697 struct ipsecrequest *isr; 1698 1699 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1700 printf("%s: using SP\n", __func__); 1701 kdebug_secpolicy(sp); 1702 } 1703 1704 /* check policy */ 1705 switch (sp->policy) { 1706 case IPSEC_POLICY_DISCARD: 1707 return 1; 1708 case IPSEC_POLICY_BYPASS: 1709 case IPSEC_POLICY_NONE: 1710 return 0; 1711 } 1712 1713 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1714 "invalid policy %u", sp->policy); 1715 1716 /* XXX should compare policy against ipsec header history */ 1717 1718 for (isr = sp->req; isr != NULL; isr = isr->next) { 1719 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1720 continue; 1721 switch (isr->saidx.proto) { 1722 case IPPROTO_ESP: 1723 if ((m->m_flags & M_DECRYPTED) == 0) { 1724 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1725 "ESP m_flags:%x\n", m->m_flags); 1726 return 1; 1727 } 1728 break; 1729 case IPPROTO_AH: 1730 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1731 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1732 "AH m_flags:%x\n", m->m_flags); 1733 return 1; 1734 } 1735 break; 1736 case IPPROTO_IPCOMP: 1737 /* 1738 * We don't really care, as IPcomp document 1739 * says that we shouldn't compress small 1740 * packets, IPComp policy should always be 1741 * treated as being in "use" level. 1742 */ 1743 break; 1744 } 1745 } 1746 1747 return 0; 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 inpcb_hdr *inph = (struct inpcb_hdr *)inp; 1759 struct secpolicy *sp; 1760 int error; 1761 int result; 1762 1763 KASSERT(m != NULL); 1764 1765 if (inph == NULL) 1766 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 1767 IP_FORWARDING, &error); 1768 else 1769 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1770 inph, &error); 1771 1772 if (sp != NULL) { 1773 result = ipsec_sp_reject(sp, m); 1774 if (result) 1775 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1776 KEY_SP_UNREF(&sp); 1777 } else { 1778 result = 0; 1779 } 1780 return result; 1781 } 1782 1783 #ifdef INET6 1784 /* 1785 * Check AH/ESP integrity. 1786 * This function is called from tcp6_input(), udp6_input(), 1787 * and {ah,esp}6_input for tunnel mode 1788 */ 1789 int 1790 ipsec6_in_reject(struct mbuf *m, struct in6pcb *in6p) 1791 { 1792 struct inpcb_hdr *inph = (struct inpcb_hdr *)in6p; 1793 struct secpolicy *sp; 1794 int error; 1795 int result; 1796 1797 KASSERT(m != NULL); 1798 1799 if (inph == NULL) 1800 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 1801 IP_FORWARDING, &error); 1802 else 1803 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1804 inph, &error); 1805 1806 if (sp != NULL) { 1807 result = ipsec_sp_reject(sp, m); 1808 if (result) 1809 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1810 KEY_SP_UNREF(&sp); 1811 } else { 1812 result = 0; 1813 } 1814 return result; 1815 } 1816 #endif 1817 1818 /* 1819 * Compute the byte size to be occupied by the IPsec header. If it is 1820 * tunneled, it includes the size of outer IP header. 1821 */ 1822 static size_t 1823 ipsec_sp_hdrsiz(const struct secpolicy *sp, const struct mbuf *m) 1824 { 1825 struct ipsecrequest *isr; 1826 size_t siz; 1827 1828 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1829 printf("%s: using SP\n", __func__); 1830 kdebug_secpolicy(sp); 1831 } 1832 1833 switch (sp->policy) { 1834 case IPSEC_POLICY_DISCARD: 1835 case IPSEC_POLICY_BYPASS: 1836 case IPSEC_POLICY_NONE: 1837 return 0; 1838 } 1839 1840 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1841 "invalid policy %u", sp->policy); 1842 1843 siz = 0; 1844 for (isr = sp->req; isr != NULL; isr = isr->next) { 1845 size_t clen = 0; 1846 struct secasvar *sav; 1847 1848 switch (isr->saidx.proto) { 1849 case IPPROTO_ESP: 1850 sav = ipsec_lookup_sa(isr, m); 1851 if (sav != NULL) { 1852 clen = esp_hdrsiz(sav); 1853 KEY_SA_UNREF(&sav); 1854 } else 1855 clen = esp_hdrsiz(NULL); 1856 break; 1857 case IPPROTO_AH: 1858 sav = ipsec_lookup_sa(isr, m); 1859 if (sav != NULL) { 1860 clen = ah_hdrsiz(sav); 1861 KEY_SA_UNREF(&sav); 1862 } else 1863 clen = ah_hdrsiz(NULL); 1864 break; 1865 case IPPROTO_IPCOMP: 1866 clen = sizeof(struct ipcomp); 1867 break; 1868 } 1869 1870 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1871 switch (isr->saidx.dst.sa.sa_family) { 1872 case AF_INET: 1873 clen += sizeof(struct ip); 1874 break; 1875 #ifdef INET6 1876 case AF_INET6: 1877 clen += sizeof(struct ip6_hdr); 1878 break; 1879 #endif 1880 default: 1881 IPSECLOG(LOG_ERR, "unknown AF %d in " 1882 "IPsec tunnel SA\n", 1883 ((const struct sockaddr *)&isr->saidx.dst) 1884 ->sa_family); 1885 break; 1886 } 1887 } 1888 siz += clen; 1889 } 1890 1891 return siz; 1892 } 1893 1894 size_t 1895 ipsec4_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1896 { 1897 struct inpcb_hdr *inph = (struct inpcb_hdr *)inp; 1898 struct secpolicy *sp; 1899 int error; 1900 size_t size; 1901 1902 KASSERT(m != NULL); 1903 KASSERTMSG(inph == NULL || inph->inph_socket != NULL, 1904 "socket w/o inpcb"); 1905 1906 if (inph == NULL) 1907 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1908 else 1909 sp = ipsec_getpolicybysock(m, dir, inph, &error); 1910 1911 if (sp != NULL) { 1912 size = ipsec_sp_hdrsiz(sp, m); 1913 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%zu.\n", size); 1914 KEY_SP_UNREF(&sp); 1915 } else { 1916 size = 0; 1917 } 1918 1919 return size; 1920 } 1921 1922 #ifdef INET6 1923 size_t 1924 ipsec6_hdrsiz(struct mbuf *m, u_int dir, struct in6pcb *in6p) 1925 { 1926 struct inpcb_hdr *inph = (struct inpcb_hdr *)in6p; 1927 struct secpolicy *sp; 1928 int error; 1929 size_t size; 1930 1931 KASSERT(m != NULL); 1932 KASSERTMSG(inph == NULL || inph->inph_socket != NULL, 1933 "socket w/o inpcb"); 1934 1935 if (inph == NULL) 1936 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1937 else 1938 sp = ipsec_getpolicybysock(m, dir, inph, &error); 1939 1940 if (sp != NULL) { 1941 size = ipsec_sp_hdrsiz(sp, m); 1942 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%zu.\n", size); 1943 KEY_SP_UNREF(&sp); 1944 } else { 1945 size = 0; 1946 } 1947 1948 return size; 1949 } 1950 #endif 1951 1952 /* 1953 * Check the variable replay window. 1954 * ipsec_chkreplay() performs replay check before ICV verification. 1955 * ipsec_updatereplay() updates replay bitmap. This must be called after 1956 * ICV verification (it also performs replay check, which is usually done 1957 * beforehand). 1958 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1959 * 1960 * based on RFC 2401. 1961 */ 1962 int 1963 ipsec_chkreplay(u_int32_t seq, const struct secasvar *sav) 1964 { 1965 const struct secreplay *replay; 1966 u_int32_t diff; 1967 int fr; 1968 u_int32_t wsizeb; /* constant: bits of window size */ 1969 int frlast; /* constant: last frame */ 1970 1971 IPSEC_SPLASSERT_SOFTNET(__func__); 1972 1973 KASSERT(sav != NULL); 1974 KASSERT(sav->replay != NULL); 1975 1976 replay = sav->replay; 1977 1978 if (replay->wsize == 0) 1979 return 1; /* no need to check replay. */ 1980 1981 /* constant */ 1982 frlast = replay->wsize - 1; 1983 wsizeb = replay->wsize << 3; 1984 1985 /* sequence number of 0 is invalid */ 1986 if (seq == 0) 1987 return 0; 1988 1989 /* first time is always okay */ 1990 if (replay->count == 0) 1991 return 1; 1992 1993 if (seq > replay->lastseq) { 1994 /* larger sequences are okay */ 1995 return 1; 1996 } else { 1997 /* seq is equal or less than lastseq. */ 1998 diff = replay->lastseq - seq; 1999 2000 /* over range to check, i.e. too old or wrapped */ 2001 if (diff >= wsizeb) 2002 return 0; 2003 2004 fr = frlast - diff / 8; 2005 2006 /* this packet already seen ? */ 2007 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2008 return 0; 2009 2010 /* out of order but good */ 2011 return 1; 2012 } 2013 } 2014 2015 /* 2016 * check replay counter whether to update or not. 2017 * OUT: 0: OK 2018 * 1: NG 2019 */ 2020 int 2021 ipsec_updatereplay(u_int32_t seq, const struct secasvar *sav) 2022 { 2023 struct secreplay *replay; 2024 u_int32_t diff; 2025 int fr; 2026 u_int32_t wsizeb; /* constant: bits of window size */ 2027 int frlast; /* constant: last frame */ 2028 2029 IPSEC_SPLASSERT_SOFTNET(__func__); 2030 2031 KASSERT(sav != NULL); 2032 KASSERT(sav->replay != NULL); 2033 2034 replay = sav->replay; 2035 2036 if (replay->wsize == 0) 2037 goto ok; /* no need to check replay. */ 2038 2039 /* constant */ 2040 frlast = replay->wsize - 1; 2041 wsizeb = replay->wsize << 3; 2042 2043 /* sequence number of 0 is invalid */ 2044 if (seq == 0) 2045 return 1; 2046 2047 /* first time */ 2048 if (replay->count == 0) { 2049 replay->lastseq = seq; 2050 memset(replay->bitmap, 0, replay->wsize); 2051 (replay->bitmap)[frlast] = 1; 2052 goto ok; 2053 } 2054 2055 if (seq > replay->lastseq) { 2056 /* seq is larger than lastseq. */ 2057 diff = seq - replay->lastseq; 2058 2059 /* new larger sequence number */ 2060 if (diff < wsizeb) { 2061 /* In window */ 2062 /* set bit for this packet */ 2063 vshiftl(replay->bitmap, diff, replay->wsize); 2064 (replay->bitmap)[frlast] |= 1; 2065 } else { 2066 /* this packet has a "way larger" */ 2067 memset(replay->bitmap, 0, replay->wsize); 2068 (replay->bitmap)[frlast] = 1; 2069 } 2070 replay->lastseq = seq; 2071 2072 /* larger is good */ 2073 } else { 2074 /* seq is equal or less than lastseq. */ 2075 diff = replay->lastseq - seq; 2076 2077 /* over range to check, i.e. too old or wrapped */ 2078 if (diff >= wsizeb) 2079 return 1; 2080 2081 fr = frlast - diff / 8; 2082 2083 /* this packet already seen ? */ 2084 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2085 return 1; 2086 2087 /* mark as seen */ 2088 (replay->bitmap)[fr] |= (1 << (diff % 8)); 2089 2090 /* out of order but good */ 2091 } 2092 2093 ok: 2094 if (replay->count == ~0) { 2095 char buf[IPSEC_LOGSASTRLEN]; 2096 2097 /* set overflow flag */ 2098 replay->overflow++; 2099 2100 /* don't increment, no more packets accepted */ 2101 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 2102 return 1; 2103 2104 IPSECLOG(LOG_WARNING, "replay counter made %d cycle. %s\n", 2105 replay->overflow, ipsec_logsastr(sav, buf, sizeof(buf))); 2106 } 2107 2108 replay->count++; 2109 2110 return 0; 2111 } 2112 2113 /* 2114 * shift variable length buffer to left. 2115 * IN: bitmap: pointer to the buffer 2116 * nbit: the number of to shift. 2117 * wsize: buffer size (bytes). 2118 */ 2119 static void 2120 vshiftl(unsigned char *bitmap, int nbit, int wsize) 2121 { 2122 int s, j, i; 2123 unsigned char over; 2124 2125 for (j = 0; j < nbit; j += 8) { 2126 s = (nbit - j < 8) ? (nbit - j): 8; 2127 bitmap[0] <<= s; 2128 for (i = 1; i < wsize; i++) { 2129 over = (bitmap[i] >> (8 - s)); 2130 bitmap[i] <<= s; 2131 bitmap[i-1] |= over; 2132 } 2133 } 2134 2135 return; 2136 } 2137 2138 /* Return a printable string for the address. */ 2139 const char * 2140 ipsec_address(const union sockaddr_union *sa, char *buf, size_t size) 2141 { 2142 switch (sa->sa.sa_family) { 2143 #if INET 2144 case AF_INET: 2145 in_print(buf, size, &sa->sin.sin_addr); 2146 return buf; 2147 #endif 2148 2149 #if INET6 2150 case AF_INET6: 2151 in6_print(buf, size, &sa->sin6.sin6_addr); 2152 return buf; 2153 #endif 2154 2155 default: 2156 return "(unknown address family)"; 2157 } 2158 } 2159 2160 const char * 2161 ipsec_logsastr(const struct secasvar *sav, char *buf, size_t size) 2162 { 2163 const struct secasindex *saidx = &sav->sah->saidx; 2164 char sbuf[IPSEC_ADDRSTRLEN], dbuf[IPSEC_ADDRSTRLEN]; 2165 2166 KASSERTMSG(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 2167 "af family mismatch, src %u, dst %u", 2168 saidx->src.sa.sa_family, saidx->dst.sa.sa_family); 2169 2170 snprintf(buf, size, "SA(SPI=%u src=%s dst=%s)", 2171 (u_int32_t)ntohl(sav->spi), 2172 ipsec_address(&saidx->src, sbuf, sizeof(sbuf)), 2173 ipsec_address(&saidx->dst, dbuf, sizeof(dbuf))); 2174 2175 return buf; 2176 } 2177 2178 void 2179 ipsec_dumpmbuf(struct mbuf *m) 2180 { 2181 int totlen; 2182 int i; 2183 u_char *p; 2184 2185 totlen = 0; 2186 printf("---\n"); 2187 while (m) { 2188 p = mtod(m, u_char *); 2189 for (i = 0; i < m->m_len; i++) { 2190 printf("%02x ", p[i]); 2191 totlen++; 2192 if (totlen % 16 == 0) 2193 printf("\n"); 2194 } 2195 m = m->m_next; 2196 } 2197 if (totlen % 16 != 0) 2198 printf("\n"); 2199 printf("---\n"); 2200 } 2201 2202 #ifdef INET6 2203 struct secpolicy * 2204 ipsec6_check_policy(struct mbuf *m, struct in6pcb *in6p, int flags, 2205 int *needipsecp, int *errorp) 2206 { 2207 struct secpolicy *sp = NULL; 2208 int s; 2209 int error = 0; 2210 int needipsec = 0; 2211 2212 if (!ipsec_outdone(m)) { 2213 s = splsoftnet(); 2214 if (in6p != NULL && 2215 ipsec_pcb_skip_ipsec(in6p->in6p_sp, IPSEC_DIR_OUTBOUND)) { 2216 splx(s); 2217 goto skippolicycheck; 2218 } 2219 sp = ipsec6_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error,in6p); 2220 2221 /* 2222 * There are four return cases: 2223 * sp != NULL apply IPsec policy 2224 * sp == NULL, error == 0 no IPsec handling needed 2225 * sp == NULL, error == -EINVAL discard packet w/o error 2226 * sp == NULL, error != 0 discard packet, report error 2227 */ 2228 2229 splx(s); 2230 if (sp == NULL) { 2231 /* 2232 * Caller must check the error return to see if it needs to discard 2233 * the packet. 2234 */ 2235 needipsec = 0; 2236 } else { 2237 needipsec = 1; 2238 } 2239 } 2240 skippolicycheck:; 2241 2242 *errorp = error; 2243 *needipsecp = needipsec; 2244 return sp; 2245 } 2246 2247 int 2248 ipsec6_input(struct mbuf *m) 2249 { 2250 struct secpolicy *sp; 2251 int s, error; 2252 2253 s = splsoftnet(); 2254 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 2255 if (sp != NULL) { 2256 /* 2257 * Check security policy against packet 2258 * attributes. 2259 */ 2260 error = ipsec_sp_reject(sp, m); 2261 KEY_SP_UNREF(&sp); 2262 } else { 2263 /* XXX error stat??? */ 2264 error = EINVAL; 2265 IPSECLOG(LOG_DEBUG, "no SP, packet discarded\n");/*XXX*/ 2266 } 2267 splx(s); 2268 2269 return error; 2270 } 2271 #endif /* INET6 */ 2272 2273 2274 2275 /* XXX this stuff doesn't belong here... */ 2276 2277 static struct xformsw *xforms = NULL; 2278 2279 /* 2280 * Register a transform; typically at system startup. 2281 */ 2282 void 2283 xform_register(struct xformsw *xsp) 2284 { 2285 xsp->xf_next = xforms; 2286 xforms = xsp; 2287 } 2288 2289 /* 2290 * Initialize transform support in an sav. 2291 */ 2292 int 2293 xform_init(struct secasvar *sav, int xftype) 2294 { 2295 struct xformsw *xsp; 2296 2297 if (sav->tdb_xform != NULL) /* previously initialized */ 2298 return 0; 2299 for (xsp = xforms; xsp; xsp = xsp->xf_next) 2300 if (xsp->xf_type == xftype) 2301 return (*xsp->xf_init)(sav, xsp); 2302 2303 IPSECLOG(LOG_DEBUG, "no match for xform type %d\n", xftype); 2304 return EINVAL; 2305 } 2306 2307 void 2308 nat_t_ports_get(struct mbuf *m, u_int16_t *dport, u_int16_t *sport) 2309 { 2310 struct m_tag *tag; 2311 2312 if ((tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL))) { 2313 *sport = ((u_int16_t *)(tag + 1))[0]; 2314 *dport = ((u_int16_t *)(tag + 1))[1]; 2315 } else 2316 *sport = *dport = 0; 2317 } 2318 2319 /* 2320 * XXXJRT This should be done as a protosw init call. 2321 */ 2322 void 2323 ipsec_attach(void) 2324 { 2325 2326 ipsec_output_init(); 2327 2328 ipsecstat_percpu = percpu_alloc(sizeof(uint64_t) * IPSEC_NSTATS); 2329 2330 sysctl_net_inet_ipsec_setup(NULL); 2331 #ifdef INET6 2332 sysctl_net_inet6_ipsec6_setup(NULL); 2333 #endif 2334 2335 ah_attach(); 2336 esp_attach(); 2337 ipcomp_attach(); 2338 ipe4_attach(); 2339 #ifdef TCP_SIGNATURE 2340 tcpsignature_attach(); 2341 #endif 2342 } 2343
Indexes created Tue Sep 23 14:10:03 GMT 2025