ipsec.c revision 1.128
1 /* $NetBSD: ipsec.c,v 1.128 2018/02/16 09:07:50 maxv Exp $ */ 2 /* $FreeBSD: /usr/local/www/cvsroot/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 1.128 2018/02/16 09:07:50 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 int ip4_ah_offsetmask = 0; /* maybe IP_DF? */ 129 int ip4_ipsec_dfbit = 2; /* DF bit on encap. 0: clear 1: set 2: copy */ 130 int ip4_esp_trans_deflev = IPSEC_LEVEL_USE; 131 int ip4_esp_net_deflev = IPSEC_LEVEL_USE; 132 int ip4_ah_trans_deflev = IPSEC_LEVEL_USE; 133 int ip4_ah_net_deflev = IPSEC_LEVEL_USE; 134 struct secpolicy ip4_def_policy; 135 int ip4_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 136 137 u_int ipsec_spdgen = 1; /* SPD generation # */ 138 139 static struct secpolicy ipsec_dummy_sp __read_mostly = { 140 .state = IPSEC_SPSTATE_ALIVE, 141 /* If ENTRUST, the dummy SP never be used. See ipsec_getpolicybysock. */ 142 .policy = IPSEC_POLICY_ENTRUST, 143 }; 144 145 static struct secpolicy *ipsec_checkpcbcache (struct mbuf *, 146 struct inpcbpolicy *, int); 147 static int ipsec_fillpcbcache (struct inpcbpolicy *, struct mbuf *, 148 struct secpolicy *, int); 149 static int ipsec_invalpcbcache (struct inpcbpolicy *, int); 150 151 /* 152 * Crypto support requirements: 153 * 154 * 1 require hardware support 155 * -1 require software support 156 * 0 take anything 157 */ 158 int crypto_support = 0; 159 160 static struct secpolicy *ipsec_getpolicybysock(struct mbuf *, u_int, 161 struct inpcb_hdr *, int *); 162 163 #ifdef INET6 164 int ip6_esp_trans_deflev = IPSEC_LEVEL_USE; 165 int ip6_esp_net_deflev = IPSEC_LEVEL_USE; 166 int ip6_ah_trans_deflev = IPSEC_LEVEL_USE; 167 int ip6_ah_net_deflev = IPSEC_LEVEL_USE; 168 struct secpolicy ip6_def_policy; 169 int ip6_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 170 #endif /* INET6 */ 171 172 static int ipsec4_setspidx_inpcb (struct mbuf *, struct inpcb *); 173 #ifdef INET6 174 static int ipsec6_setspidx_in6pcb (struct mbuf *, struct in6pcb *); 175 #endif 176 static int ipsec_setspidx (struct mbuf *, struct secpolicyindex *, int); 177 static void ipsec4_get_ulp (struct mbuf *m, struct secpolicyindex *, int); 178 static int ipsec4_setspidx_ipaddr (struct mbuf *, struct secpolicyindex *); 179 #ifdef INET6 180 static void ipsec6_get_ulp (struct mbuf *m, struct secpolicyindex *, int); 181 static int ipsec6_setspidx_ipaddr (struct mbuf *, struct secpolicyindex *); 182 #endif 183 static void ipsec_delpcbpolicy (struct inpcbpolicy *); 184 #if 0 /* unused */ 185 static struct secpolicy *ipsec_deepcopy_policy (const struct secpolicy *); 186 #endif 187 static int ipsec_set_policy (struct secpolicy **, int, const void *, size_t, 188 kauth_cred_t); 189 static int ipsec_get_policy (struct secpolicy *, struct mbuf **); 190 static void ipsec_destroy_policy(struct secpolicy *); 191 static void vshiftl (unsigned char *, int, int); 192 static size_t ipsec_hdrsiz(const struct secpolicy *, const struct mbuf *); 193 194 /* 195 * Try to validate and use cached policy on a PCB. 196 */ 197 static struct secpolicy * 198 ipsec_checkpcbcache(struct mbuf *m, struct inpcbpolicy *pcbsp, int dir) 199 { 200 struct secpolicyindex spidx; 201 struct secpolicy *sp = NULL; 202 int s; 203 204 KASSERT(IPSEC_DIR_IS_VALID(dir)); 205 KASSERT(pcbsp != NULL); 206 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 207 KASSERT(inph_locked(pcbsp->sp_inph)); 208 209 /* 210 * Checking the generation and sp->state and taking a reference to an SP 211 * must be in a critical section of pserialize. See key_unlink_sp. 212 */ 213 s = pserialize_read_enter(); 214 /* SPD table change invalidate all the caches. */ 215 if (ipsec_spdgen != pcbsp->sp_cache[dir].cachegen) { 216 ipsec_invalpcbcache(pcbsp, dir); 217 goto out; 218 } 219 sp = pcbsp->sp_cache[dir].cachesp; 220 if (sp == NULL) 221 goto out; 222 if (sp->state != IPSEC_SPSTATE_ALIVE) { 223 sp = NULL; 224 ipsec_invalpcbcache(pcbsp, dir); 225 goto out; 226 } 227 if ((pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) == 0) { 228 /* NB: assume ipsec_setspidx never sleep */ 229 if (ipsec_setspidx(m, &spidx, 1) != 0) { 230 sp = NULL; 231 goto out; 232 } 233 234 /* 235 * We have to make an exact match here since the cached rule 236 * might have lower priority than a rule that would otherwise 237 * have matched the packet. 238 */ 239 if (memcmp(&pcbsp->sp_cache[dir].cacheidx, &spidx, 240 sizeof(spidx))) { 241 sp = NULL; 242 goto out; 243 } 244 } else { 245 /* 246 * The pcb is connected, and the L4 code is sure that: 247 * - outgoing side uses inp_[lf]addr 248 * - incoming side looks up policy after inpcb lookup 249 * and address pair is know to be stable. We do not need 250 * to generate spidx again, nor check the address match again. 251 * 252 * For IPv4/v6 SOCK_STREAM sockets, this assumptions holds 253 * and there are calls to ipsec_pcbconn() from in_pcbconnect(). 254 */ 255 } 256 257 sp->lastused = time_second; 258 KEY_SP_REF(sp); 259 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 260 "DP cause refcnt++:%d SP:%p\n", 261 key_sp_refcnt(sp), pcbsp->sp_cache[dir].cachesp); 262 out: 263 pserialize_read_exit(s); 264 return sp; 265 } 266 267 static int 268 ipsec_fillpcbcache(struct inpcbpolicy *pcbsp, struct mbuf *m, 269 struct secpolicy *sp, int dir) 270 { 271 272 KASSERT(IPSEC_DIR_IS_INOROUT(dir)); 273 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 274 KASSERT(inph_locked(pcbsp->sp_inph)); 275 276 pcbsp->sp_cache[dir].cachesp = NULL; 277 pcbsp->sp_cache[dir].cachehint = IPSEC_PCBHINT_UNKNOWN; 278 if (ipsec_setspidx(m, &pcbsp->sp_cache[dir].cacheidx, 1) != 0) { 279 return EINVAL; 280 } 281 pcbsp->sp_cache[dir].cachesp = sp; 282 if (pcbsp->sp_cache[dir].cachesp) { 283 /* 284 * If the PCB is connected, we can remember a hint to 285 * possibly short-circuit IPsec processing in other places. 286 */ 287 if (pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) { 288 switch (pcbsp->sp_cache[dir].cachesp->policy) { 289 case IPSEC_POLICY_NONE: 290 case IPSEC_POLICY_BYPASS: 291 pcbsp->sp_cache[dir].cachehint = 292 IPSEC_PCBHINT_NO; 293 break; 294 default: 295 pcbsp->sp_cache[dir].cachehint = 296 IPSEC_PCBHINT_YES; 297 } 298 } 299 } 300 pcbsp->sp_cache[dir].cachegen = ipsec_spdgen; 301 302 return 0; 303 } 304 305 static int 306 ipsec_invalpcbcache(struct inpcbpolicy *pcbsp, int dir) 307 { 308 int i; 309 310 KASSERT(inph_locked(pcbsp->sp_inph)); 311 312 for (i = IPSEC_DIR_INBOUND; i <= IPSEC_DIR_OUTBOUND; i++) { 313 if (dir != IPSEC_DIR_ANY && i != dir) 314 continue; 315 pcbsp->sp_cache[i].cachesp = NULL; 316 pcbsp->sp_cache[i].cachehint = IPSEC_PCBHINT_UNKNOWN; 317 pcbsp->sp_cache[i].cachegen = 0; 318 memset(&pcbsp->sp_cache[i].cacheidx, 0, 319 sizeof(pcbsp->sp_cache[i].cacheidx)); 320 } 321 return 0; 322 } 323 324 void 325 ipsec_pcbconn(struct inpcbpolicy *pcbsp) 326 { 327 328 KASSERT(inph_locked(pcbsp->sp_inph)); 329 330 pcbsp->sp_cacheflags |= IPSEC_PCBSP_CONNECTED; 331 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 332 } 333 334 void 335 ipsec_pcbdisconn(struct inpcbpolicy *pcbsp) 336 { 337 338 KASSERT(inph_locked(pcbsp->sp_inph)); 339 340 pcbsp->sp_cacheflags &= ~IPSEC_PCBSP_CONNECTED; 341 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 342 } 343 344 void 345 ipsec_invalpcbcacheall(void) 346 { 347 348 if (ipsec_spdgen == UINT_MAX) 349 ipsec_spdgen = 1; 350 else 351 ipsec_spdgen++; 352 } 353 354 /* 355 * Return a held reference to the default SP. 356 */ 357 static struct secpolicy * 358 key_get_default_sp(int af, const char *where, int tag) 359 { 360 struct secpolicy *sp; 361 362 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP from %s:%u\n", where, tag); 363 364 switch(af) { 365 case AF_INET: 366 sp = &ip4_def_policy; 367 break; 368 #ifdef INET6 369 case AF_INET6: 370 sp = &ip6_def_policy; 371 break; 372 #endif 373 default: 374 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 375 "unexpected protocol family %u\n", af); 376 return NULL; 377 } 378 379 if (sp->policy != IPSEC_POLICY_DISCARD && 380 sp->policy != IPSEC_POLICY_NONE) { 381 IPSECLOG(LOG_INFO, "fixed system default policy: %d->%d\n", 382 sp->policy, IPSEC_POLICY_NONE); 383 sp->policy = IPSEC_POLICY_NONE; 384 } 385 KEY_SP_REF(sp); 386 387 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP returns SP:%p (%u)\n", 388 sp, key_sp_refcnt(sp)); 389 return sp; 390 } 391 #define KEY_GET_DEFAULT_SP(af) \ 392 key_get_default_sp((af), __func__, __LINE__) 393 394 /* 395 * For OUTBOUND packet having a socket. Searching SPD for packet, 396 * and return a pointer to SP. 397 * OUT: NULL: no apropreate SP found, the following value is set to error. 398 * 0 : bypass 399 * EACCES : discard packet. 400 * ENOENT : ipsec_acquire() in progress, maybe. 401 * others : error occurred. 402 * others: a pointer to SP 403 * 404 * NOTE: IPv6 mapped address concern is implemented here. 405 */ 406 static struct secpolicy * 407 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb_hdr *inph, 408 int *error) 409 { 410 struct inpcbpolicy *pcbsp = NULL; 411 struct secpolicy *currsp = NULL; /* policy on socket */ 412 struct secpolicy *sp; 413 int af; 414 415 KASSERT(m != NULL); 416 KASSERT(inph != NULL); 417 KASSERT(error != NULL); 418 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 419 420 KASSERT(inph->inph_socket != NULL); 421 KASSERT(inph_locked(inph)); 422 423 /* XXX FIXME inpcb/in6pcb vs socket*/ 424 af = inph->inph_af; 425 KASSERTMSG(af == AF_INET || af == AF_INET6, 426 "unexpected protocol family %u", af); 427 428 KASSERT(inph->inph_sp != NULL); 429 /* If we have a cached entry, and if it is still valid, use it. */ 430 IPSEC_STATINC(IPSEC_STAT_SPDCACHELOOKUP); 431 currsp = ipsec_checkpcbcache(m, inph->inph_sp, dir); 432 if (currsp) { 433 *error = 0; 434 return currsp; 435 } 436 IPSEC_STATINC(IPSEC_STAT_SPDCACHEMISS); 437 438 switch (af) { 439 case AF_INET: { 440 struct inpcb *in4p = (struct inpcb *)inph; 441 /* set spidx in pcb */ 442 *error = ipsec4_setspidx_inpcb(m, in4p); 443 pcbsp = in4p->inp_sp; 444 break; 445 } 446 447 #if defined(INET6) 448 case AF_INET6: { 449 struct in6pcb *in6p = (struct in6pcb *)inph; 450 /* set spidx in pcb */ 451 *error = ipsec6_setspidx_in6pcb(m, in6p); 452 pcbsp = in6p->in6p_sp; 453 break; 454 } 455 #endif 456 default: 457 *error = EPFNOSUPPORT; 458 break; 459 } 460 if (*error) 461 return NULL; 462 463 KASSERT(pcbsp != NULL); 464 switch (dir) { 465 case IPSEC_DIR_INBOUND: 466 currsp = pcbsp->sp_in; 467 break; 468 case IPSEC_DIR_OUTBOUND: 469 currsp = pcbsp->sp_out; 470 break; 471 } 472 KASSERT(currsp != NULL); 473 474 if (pcbsp->priv) { /* when privilieged socket */ 475 switch (currsp->policy) { 476 case IPSEC_POLICY_BYPASS: 477 case IPSEC_POLICY_IPSEC: 478 KEY_SP_REF(currsp); 479 sp = currsp; 480 break; 481 482 case IPSEC_POLICY_ENTRUST: 483 /* look for a policy in SPD */ 484 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 485 if (sp == NULL) /* no SP found */ 486 sp = KEY_GET_DEFAULT_SP(af); 487 break; 488 489 default: 490 IPSECLOG(LOG_ERR, "Invalid policy for PCB %d\n", 491 currsp->policy); 492 *error = EINVAL; 493 return NULL; 494 } 495 } else { /* unpriv, SPD has policy */ 496 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 497 if (sp == NULL) { /* no SP found */ 498 switch (currsp->policy) { 499 case IPSEC_POLICY_BYPASS: 500 IPSECLOG(LOG_ERR, "Illegal policy for " 501 "non-priviliged defined %d\n", 502 currsp->policy); 503 *error = EINVAL; 504 return NULL; 505 506 case IPSEC_POLICY_ENTRUST: 507 sp = KEY_GET_DEFAULT_SP(af); 508 break; 509 510 case IPSEC_POLICY_IPSEC: 511 KEY_SP_REF(currsp); 512 sp = currsp; 513 break; 514 515 default: 516 IPSECLOG(LOG_ERR, "Invalid policy for " 517 "PCB %d\n", currsp->policy); 518 *error = EINVAL; 519 return NULL; 520 } 521 } 522 } 523 KASSERTMSG(sp != NULL, "null SP (priv %u policy %u", pcbsp->priv, 524 currsp->policy); 525 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 526 "DP (priv %u policy %u) allocates SP:%p (refcnt %u)\n", 527 pcbsp->priv, currsp->policy, sp, key_sp_refcnt(sp)); 528 ipsec_fillpcbcache(pcbsp, m, sp, dir); 529 return sp; 530 } 531 532 /* 533 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 534 * and return a pointer to SP. 535 * OUT: positive: a pointer to the entry for security policy leaf matched. 536 * NULL: no apropreate SP found, the following value is set to error. 537 * 0 : bypass 538 * EACCES : discard packet. 539 * ENOENT : ipsec_acquire() in progress, maybe. 540 * others : error occurred. 541 */ 542 struct secpolicy * 543 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 544 { 545 struct secpolicyindex spidx; 546 struct secpolicy *sp; 547 548 KASSERT(m != NULL); 549 KASSERT(error != NULL); 550 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 551 552 sp = NULL; 553 554 /* Make an index to look for a policy. */ 555 *error = ipsec_setspidx(m, &spidx, (flag & IP_FORWARDING) ? 0 : 1); 556 if (*error != 0) { 557 IPSECLOG(LOG_DEBUG, "setpidx failed, dir %u flag %u\n", dir, flag); 558 memset(&spidx, 0, sizeof (spidx)); 559 return NULL; 560 } 561 562 spidx.dir = dir; 563 564 if (key_havesp(dir)) { 565 sp = KEY_LOOKUP_SP_BYSPIDX(&spidx, dir); 566 } 567 568 if (sp == NULL) /* no SP found, use system default */ 569 sp = KEY_GET_DEFAULT_SP(spidx.dst.sa.sa_family); 570 KASSERT(sp != NULL); 571 return sp; 572 } 573 574 struct secpolicy * 575 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 576 struct inpcb *inp) 577 { 578 struct secpolicy *sp; 579 580 *error = 0; 581 582 if (inp == NULL) { 583 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 584 } else { 585 KASSERT(inp->inp_socket != NULL); 586 sp = ipsec_getpolicybysock(m, dir, (struct inpcb_hdr *)inp, error); 587 } 588 if (sp == NULL) { 589 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 590 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 591 return NULL; 592 } 593 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 594 switch (sp->policy) { 595 case IPSEC_POLICY_ENTRUST: 596 default: 597 printf("%s: invalid policy %u\n", __func__, sp->policy); 598 /* fall thru... */ 599 case IPSEC_POLICY_DISCARD: 600 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 601 *error = -EINVAL; /* packet is discarded by caller */ 602 break; 603 case IPSEC_POLICY_BYPASS: 604 case IPSEC_POLICY_NONE: 605 KEY_SP_UNREF(&sp); 606 sp = NULL; /* NB: force NULL result */ 607 break; 608 case IPSEC_POLICY_IPSEC: 609 KASSERT(sp->req != NULL); 610 break; 611 } 612 if (*error != 0) { 613 KEY_SP_UNREF(&sp); 614 sp = NULL; 615 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 616 } 617 return sp; 618 } 619 620 int 621 ipsec4_output(struct mbuf *m, struct inpcb *inp, int flags, 622 u_long *mtu, bool *natt_frag, bool *done) 623 { 624 struct secpolicy *sp = NULL; 625 int error, s; 626 627 /* 628 * Check the security policy (SP) for the packet and, if required, 629 * do IPsec-related processing. There are two cases here; the first 630 * time a packet is sent through it will be untagged and handled by 631 * ipsec4_checkpolicy(). If the packet is resubmitted to ip_output 632 * (e.g. after AH, ESP, etc. processing), there will be a tag to 633 * bypass the lookup and related policy checking. 634 */ 635 if (ipsec_outdone(m)) { 636 return 0; 637 } 638 s = splsoftnet(); 639 if (inp && ipsec_pcb_skip_ipsec(inp->inp_sp, IPSEC_DIR_OUTBOUND)) { 640 splx(s); 641 return 0; 642 } 643 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, inp); 644 645 /* 646 * There are four return cases: 647 * sp != NULL apply IPsec policy 648 * sp == NULL, error == 0 no IPsec handling needed 649 * sp == NULL, error == -EINVAL discard packet w/o error 650 * sp == NULL, error != 0 discard packet, report error 651 */ 652 if (sp == NULL) { 653 splx(s); 654 if (error) { 655 /* 656 * Hack: -EINVAL is used to signal that a packet 657 * should be silently discarded. This is typically 658 * because we asked key management for an SA and 659 * it was delayed (e.g. kicked up to IKE). 660 */ 661 if (error == -EINVAL) 662 error = 0; 663 m_freem(m); 664 *done = true; 665 return error; 666 } 667 /* No IPsec processing for this packet. */ 668 return 0; 669 } 670 671 /* 672 * Do delayed checksums now because we send before 673 * this is done in the normal processing path. 674 */ 675 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 676 in_delayed_cksum(m); 677 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 678 } 679 680 { 681 u_long _mtu = 0; 682 683 /* Note: callee frees mbuf */ 684 error = ipsec4_process_packet(m, sp->req, &_mtu); 685 686 if (error == 0 && _mtu != 0) { 687 /* 688 * NAT-T ESP fragmentation: do not do IPSec processing 689 * now, we will do it on each fragmented packet. 690 */ 691 *mtu = _mtu; 692 *natt_frag = true; 693 KEY_SP_UNREF(&sp); 694 splx(s); 695 return 0; 696 } 697 } 698 /* 699 * Preserve KAME behaviour: ENOENT can be returned 700 * when an SA acquire is in progress. Don't propagate 701 * this to user-level; it confuses applications. 702 * 703 * XXX this will go away when the SADB is redone. 704 */ 705 if (error == ENOENT) 706 error = 0; 707 KEY_SP_UNREF(&sp); 708 splx(s); 709 *done = true; 710 return error; 711 } 712 713 int 714 ipsec4_input(struct mbuf *m, int flags) 715 { 716 struct secpolicy *sp; 717 int error, s; 718 719 s = splsoftnet(); 720 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 721 if (sp == NULL) { 722 splx(s); 723 return EINVAL; 724 } 725 726 /* 727 * Check security policy against packet attributes. 728 */ 729 error = ipsec_in_reject(sp, m); 730 KEY_SP_UNREF(&sp); 731 splx(s); 732 if (error) { 733 return error; 734 } 735 736 if (flags == 0) { 737 /* We are done. */ 738 return 0; 739 } 740 741 /* 742 * Peek at the outbound SP for this packet to determine if 743 * it is a Fast Forward candidate. 744 */ 745 s = splsoftnet(); 746 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, NULL); 747 if (sp != NULL) { 748 m->m_flags &= ~M_CANFASTFWD; 749 KEY_SP_UNREF(&sp); 750 } 751 splx(s); 752 return 0; 753 } 754 755 int 756 ipsec4_forward(struct mbuf *m, int *destmtu) 757 { 758 /* 759 * If the packet is routed over IPsec tunnel, tell the 760 * originator the tunnel MTU. 761 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 762 * XXX quickhack!!! 763 */ 764 struct secpolicy *sp; 765 size_t ipsechdr; 766 int error; 767 768 sp = ipsec4_getpolicybyaddr(m, 769 IPSEC_DIR_OUTBOUND, IP_FORWARDING, &error); 770 if (sp == NULL) { 771 return EINVAL; 772 } 773 774 /* Count IPsec header size. */ 775 ipsechdr = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, NULL); 776 777 /* 778 * Find the correct route for outer IPv4 header, compute tunnel MTU. 779 */ 780 if (sp->req) { 781 struct secasvar *sav; 782 783 sav = ipsec_lookup_sa(sp->req, m); 784 if (sav != NULL) { 785 struct route *ro; 786 struct rtentry *rt; 787 788 ro = &sav->sah->sa_route; 789 rt = rtcache_validate(ro); 790 if (rt && rt->rt_ifp) { 791 *destmtu = rt->rt_rmx.rmx_mtu ? 792 rt->rt_rmx.rmx_mtu : rt->rt_ifp->if_mtu; 793 *destmtu -= ipsechdr; 794 } 795 rtcache_unref(rt, ro); 796 KEY_SA_UNREF(&sav); 797 } 798 } 799 KEY_SP_UNREF(&sp); 800 return 0; 801 } 802 803 #ifdef INET6 804 struct secpolicy * 805 ipsec6_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 806 struct in6pcb *in6p) 807 { 808 struct secpolicy *sp; 809 810 *error = 0; 811 812 if (in6p == NULL) { 813 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 814 } else { 815 KASSERT(in6p->in6p_socket != NULL); 816 sp = ipsec_getpolicybysock(m, dir, (struct inpcb_hdr *)in6p, error); 817 } 818 if (sp == NULL) { 819 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 820 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 821 return NULL; 822 } 823 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 824 switch (sp->policy) { 825 case IPSEC_POLICY_ENTRUST: 826 default: 827 printf("%s: invalid policy %u\n", __func__, sp->policy); 828 /* fall thru... */ 829 case IPSEC_POLICY_DISCARD: 830 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 831 *error = -EINVAL; /* packet is discarded by caller */ 832 break; 833 case IPSEC_POLICY_BYPASS: 834 case IPSEC_POLICY_NONE: 835 KEY_SP_UNREF(&sp); 836 sp = NULL; /* NB: force NULL result */ 837 break; 838 case IPSEC_POLICY_IPSEC: 839 KASSERT(sp->req != NULL); 840 break; 841 } 842 if (*error != 0) { 843 KEY_SP_UNREF(&sp); 844 sp = NULL; 845 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 846 } 847 return sp; 848 } 849 #endif /* INET6 */ 850 851 static int 852 ipsec4_setspidx_inpcb(struct mbuf *m, struct inpcb *pcb) 853 { 854 int error; 855 856 KASSERT(pcb != NULL); 857 KASSERT(pcb->inp_sp != NULL); 858 KASSERT(pcb->inp_sp->sp_out != NULL); 859 KASSERT(pcb->inp_sp->sp_in != NULL); 860 861 error = ipsec_setspidx(m, &pcb->inp_sp->sp_in->spidx, 1); 862 if (error == 0) { 863 pcb->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 864 pcb->inp_sp->sp_out->spidx = pcb->inp_sp->sp_in->spidx; 865 pcb->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 866 } else { 867 memset(&pcb->inp_sp->sp_in->spidx, 0, 868 sizeof(pcb->inp_sp->sp_in->spidx)); 869 memset(&pcb->inp_sp->sp_out->spidx, 0, 870 sizeof(pcb->inp_sp->sp_in->spidx)); 871 } 872 return error; 873 } 874 875 #ifdef INET6 876 static int 877 ipsec6_setspidx_in6pcb(struct mbuf *m, struct in6pcb *pcb) 878 { 879 struct secpolicyindex *spidx; 880 int error; 881 882 KASSERT(pcb != NULL); 883 KASSERT(pcb->in6p_sp != NULL); 884 KASSERT(pcb->in6p_sp->sp_out != NULL); 885 KASSERT(pcb->in6p_sp->sp_in != NULL); 886 887 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 888 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 889 890 spidx = &pcb->in6p_sp->sp_in->spidx; 891 error = ipsec_setspidx(m, spidx, 1); 892 if (error) 893 goto bad; 894 spidx->dir = IPSEC_DIR_INBOUND; 895 896 spidx = &pcb->in6p_sp->sp_out->spidx; 897 error = ipsec_setspidx(m, spidx, 1); 898 if (error) 899 goto bad; 900 spidx->dir = IPSEC_DIR_OUTBOUND; 901 902 return 0; 903 904 bad: 905 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 906 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 907 return error; 908 } 909 #endif 910 911 /* 912 * configure security policy index (src/dst/proto/sport/dport) 913 * by looking at the content of mbuf. 914 * the caller is responsible for error recovery (like clearing up spidx). 915 */ 916 static int 917 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 918 { 919 struct ip *ip = NULL; 920 struct ip ipbuf; 921 u_int v; 922 struct mbuf *n; 923 int len; 924 int error; 925 926 KASSERT(m != NULL); 927 928 /* 929 * validate m->m_pkthdr.len. we see incorrect length if we 930 * mistakenly call this function with inconsistent mbuf chain 931 * (like 4.4BSD tcp/udp processing). XXX should we panic here? 932 */ 933 len = 0; 934 for (n = m; n; n = n->m_next) 935 len += n->m_len; 936 if (m->m_pkthdr.len != len) { 937 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 938 "total of m_len(%d) != pkthdr.len(%d), ignored.\n", 939 len, m->m_pkthdr.len); 940 return EINVAL; 941 } 942 943 if (m->m_pkthdr.len < sizeof(struct ip)) { 944 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 945 "pkthdr.len(%d) < sizeof(struct ip), ignored.\n", 946 m->m_pkthdr.len); 947 return EINVAL; 948 } 949 950 if (m->m_len >= sizeof(*ip)) 951 ip = mtod(m, struct ip *); 952 else { 953 m_copydata(m, 0, sizeof(ipbuf), &ipbuf); 954 ip = &ipbuf; 955 } 956 v = ip->ip_v; 957 switch (v) { 958 case 4: 959 error = ipsec4_setspidx_ipaddr(m, spidx); 960 if (error) 961 return error; 962 ipsec4_get_ulp(m, spidx, needport); 963 return 0; 964 #ifdef INET6 965 case 6: 966 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 967 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 968 "pkthdr.len(%d) < sizeof(struct ip6_hdr), " 969 "ignored.\n", m->m_pkthdr.len); 970 return EINVAL; 971 } 972 error = ipsec6_setspidx_ipaddr(m, spidx); 973 if (error) 974 return error; 975 ipsec6_get_ulp(m, spidx, needport); 976 return 0; 977 #endif 978 default: 979 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 980 "unknown IP version %u, ignored.\n", v); 981 return EINVAL; 982 } 983 } 984 985 static void 986 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 987 { 988 u_int8_t nxt; 989 int off; 990 991 /* sanity check */ 992 KASSERT(m != NULL); 993 KASSERTMSG(m->m_pkthdr.len >= sizeof(struct ip), "packet too short"); 994 995 /* NB: ip_input() flips it into host endian XXX need more checking */ 996 if (m->m_len >= sizeof(struct ip)) { 997 struct ip *ip = mtod(m, struct ip *); 998 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 999 goto done; 1000 off = ip->ip_hl << 2; 1001 nxt = ip->ip_p; 1002 } else { 1003 struct ip ih; 1004 1005 m_copydata(m, 0, sizeof (struct ip), &ih); 1006 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 1007 goto done; 1008 off = ih.ip_hl << 2; 1009 nxt = ih.ip_p; 1010 } 1011 1012 while (off < m->m_pkthdr.len) { 1013 struct ip6_ext ip6e; 1014 struct tcphdr th; 1015 struct udphdr uh; 1016 struct icmp icmph; 1017 1018 switch (nxt) { 1019 case IPPROTO_TCP: 1020 spidx->ul_proto = nxt; 1021 if (!needport) 1022 goto done_proto; 1023 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1024 goto done; 1025 m_copydata(m, off, sizeof (th), &th); 1026 spidx->src.sin.sin_port = th.th_sport; 1027 spidx->dst.sin.sin_port = th.th_dport; 1028 return; 1029 case IPPROTO_UDP: 1030 spidx->ul_proto = nxt; 1031 if (!needport) 1032 goto done_proto; 1033 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1034 goto done; 1035 m_copydata(m, off, sizeof (uh), &uh); 1036 spidx->src.sin.sin_port = uh.uh_sport; 1037 spidx->dst.sin.sin_port = uh.uh_dport; 1038 return; 1039 case IPPROTO_AH: 1040 if (m->m_pkthdr.len > off + sizeof(ip6e)) 1041 goto done; 1042 /* XXX sigh, this works but is totally bogus */ 1043 m_copydata(m, off, sizeof(ip6e), &ip6e); 1044 off += (ip6e.ip6e_len + 2) << 2; 1045 nxt = ip6e.ip6e_nxt; 1046 break; 1047 case IPPROTO_ICMP: 1048 spidx->ul_proto = nxt; 1049 if (off + sizeof(struct icmp) > m->m_pkthdr.len) 1050 return; 1051 m_copydata(m, off, sizeof(icmph), &icmph); 1052 ((struct sockaddr_in *)&spidx->src)->sin_port = 1053 htons((uint16_t)icmph.icmp_type); 1054 ((struct sockaddr_in *)&spidx->dst)->sin_port = 1055 htons((uint16_t)icmph.icmp_code); 1056 return; 1057 default: 1058 /* XXX intermediate headers??? */ 1059 spidx->ul_proto = nxt; 1060 goto done_proto; 1061 } 1062 } 1063 done: 1064 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1065 done_proto: 1066 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 1067 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 1068 } 1069 1070 /* assumes that m is sane */ 1071 static int 1072 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1073 { 1074 static const struct sockaddr_in template = { 1075 sizeof (struct sockaddr_in), 1076 AF_INET, 1077 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 1078 }; 1079 1080 spidx->src.sin = template; 1081 spidx->dst.sin = template; 1082 1083 if (m->m_len < sizeof (struct ip)) { 1084 m_copydata(m, offsetof(struct ip, ip_src), 1085 sizeof(struct in_addr), &spidx->src.sin.sin_addr); 1086 m_copydata(m, offsetof(struct ip, ip_dst), 1087 sizeof(struct in_addr), &spidx->dst.sin.sin_addr); 1088 } else { 1089 struct ip *ip = mtod(m, struct ip *); 1090 spidx->src.sin.sin_addr = ip->ip_src; 1091 spidx->dst.sin.sin_addr = ip->ip_dst; 1092 } 1093 1094 spidx->prefs = sizeof(struct in_addr) << 3; 1095 spidx->prefd = sizeof(struct in_addr) << 3; 1096 1097 return 0; 1098 } 1099 1100 #ifdef INET6 1101 static void 1102 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, 1103 int needport) 1104 { 1105 int off, nxt; 1106 struct tcphdr th; 1107 struct udphdr uh; 1108 struct icmp6_hdr icmph; 1109 1110 KASSERT(m != NULL); 1111 1112 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1113 kdebug_mbuf(__func__, m); 1114 } 1115 1116 /* set default */ 1117 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1118 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 1119 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 1120 1121 nxt = -1; 1122 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 1123 if (off < 0 || m->m_pkthdr.len < off) 1124 return; 1125 1126 switch (nxt) { 1127 case IPPROTO_TCP: 1128 spidx->ul_proto = nxt; 1129 if (!needport) 1130 break; 1131 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1132 break; 1133 m_copydata(m, off, sizeof(th), &th); 1134 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 1135 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 1136 break; 1137 case IPPROTO_UDP: 1138 spidx->ul_proto = nxt; 1139 if (!needport) 1140 break; 1141 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1142 break; 1143 m_copydata(m, off, sizeof(uh), &uh); 1144 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 1145 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 1146 break; 1147 case IPPROTO_ICMPV6: 1148 spidx->ul_proto = nxt; 1149 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 1150 break; 1151 m_copydata(m, off, sizeof(icmph), &icmph); 1152 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 1153 htons((uint16_t)icmph.icmp6_type); 1154 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 1155 htons((uint16_t)icmph.icmp6_code); 1156 break; 1157 default: 1158 /* XXX intermediate headers??? */ 1159 spidx->ul_proto = nxt; 1160 break; 1161 } 1162 } 1163 1164 /* assumes that m is sane */ 1165 static int 1166 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1167 { 1168 struct ip6_hdr *ip6 = NULL; 1169 struct ip6_hdr ip6buf; 1170 struct sockaddr_in6 *sin6; 1171 1172 if (m->m_len >= sizeof(*ip6)) 1173 ip6 = mtod(m, struct ip6_hdr *); 1174 else { 1175 m_copydata(m, 0, sizeof(ip6buf), &ip6buf); 1176 ip6 = &ip6buf; 1177 } 1178 1179 sin6 = (struct sockaddr_in6 *)&spidx->src; 1180 memset(sin6, 0, sizeof(*sin6)); 1181 sin6->sin6_family = AF_INET6; 1182 sin6->sin6_len = sizeof(struct sockaddr_in6); 1183 memcpy(&sin6->sin6_addr, &ip6->ip6_src, sizeof(ip6->ip6_src)); 1184 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 1185 sin6->sin6_addr.s6_addr16[1] = 0; 1186 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 1187 } 1188 spidx->prefs = sizeof(struct in6_addr) << 3; 1189 1190 sin6 = (struct sockaddr_in6 *)&spidx->dst; 1191 memset(sin6, 0, sizeof(*sin6)); 1192 sin6->sin6_family = AF_INET6; 1193 sin6->sin6_len = sizeof(struct sockaddr_in6); 1194 memcpy(&sin6->sin6_addr, &ip6->ip6_dst, sizeof(ip6->ip6_dst)); 1195 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 1196 sin6->sin6_addr.s6_addr16[1] = 0; 1197 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 1198 } 1199 spidx->prefd = sizeof(struct in6_addr) << 3; 1200 1201 return 0; 1202 } 1203 #endif 1204 1205 static void 1206 ipsec_delpcbpolicy(struct inpcbpolicy *p) 1207 { 1208 1209 kmem_intr_free(p, sizeof(*p)); 1210 } 1211 1212 /* initialize policy in PCB */ 1213 int 1214 ipsec_init_policy(struct socket *so, struct inpcbpolicy **policy) 1215 { 1216 struct inpcbpolicy *new; 1217 1218 KASSERT(so != NULL); 1219 KASSERT(policy != NULL); 1220 1221 new = kmem_intr_zalloc(sizeof(*new), KM_NOSLEEP); 1222 if (new == NULL) { 1223 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1224 return ENOBUFS; 1225 } 1226 1227 if (IPSEC_PRIVILEGED_SO(so)) 1228 new->priv = 1; 1229 else 1230 new->priv = 0; 1231 1232 /* 1233 * Set dummy SPs. Actual SPs will be allocated later if needed. 1234 */ 1235 new->sp_in = &ipsec_dummy_sp; 1236 new->sp_out = &ipsec_dummy_sp; 1237 1238 *policy = new; 1239 1240 return 0; 1241 } 1242 1243 #if 0 /* unused */ 1244 /* copy old ipsec policy into new */ 1245 int 1246 ipsec_copy_policy(const struct inpcbpolicy *old, struct inpcbpolicy *new) 1247 { 1248 struct secpolicy *sp; 1249 1250 sp = ipsec_deepcopy_policy(old->sp_in); 1251 if (sp) { 1252 KEY_SP_UNREF(&new->sp_in); 1253 new->sp_in = sp; 1254 } else 1255 return ENOBUFS; 1256 1257 sp = ipsec_deepcopy_policy(old->sp_out); 1258 if (sp) { 1259 KEY_SP_UNREF(&new->sp_out); 1260 new->sp_out = sp; 1261 } else 1262 return ENOBUFS; 1263 1264 new->priv = old->priv; 1265 1266 return 0; 1267 } 1268 1269 /* deep-copy a policy in PCB */ 1270 static struct secpolicy * 1271 ipsec_deepcopy_policy(const struct secpolicy *src) 1272 { 1273 struct ipsecrequest *newchain = NULL; 1274 const struct ipsecrequest *p; 1275 struct ipsecrequest **q; 1276 struct secpolicy *dst; 1277 1278 if (src == NULL) 1279 return NULL; 1280 dst = KEY_NEWSP(); 1281 if (dst == NULL) 1282 return NULL; 1283 1284 /* 1285 * deep-copy IPsec request chain. This is required since struct 1286 * ipsecrequest is not reference counted. 1287 */ 1288 q = &newchain; 1289 for (p = src->req; p; p = p->next) { 1290 *q = kmem_zalloc(sizeof(**q), KM_SLEEP); 1291 (*q)->next = NULL; 1292 1293 (*q)->saidx.proto = p->saidx.proto; 1294 (*q)->saidx.mode = p->saidx.mode; 1295 (*q)->level = p->level; 1296 (*q)->saidx.reqid = p->saidx.reqid; 1297 1298 memcpy(&(*q)->saidx.src, &p->saidx.src, sizeof((*q)->saidx.src)); 1299 memcpy(&(*q)->saidx.dst, &p->saidx.dst, sizeof((*q)->saidx.dst)); 1300 1301 (*q)->sp = dst; 1302 1303 q = &((*q)->next); 1304 } 1305 1306 dst->req = newchain; 1307 dst->state = src->state; 1308 dst->policy = src->policy; 1309 /* do not touch the refcnt fields */ 1310 1311 return dst; 1312 } 1313 #endif 1314 1315 static void 1316 ipsec_destroy_policy(struct secpolicy *sp) 1317 { 1318 1319 if (sp == &ipsec_dummy_sp) 1320 ; /* It's dummy. No need to free it. */ 1321 else { 1322 /* 1323 * We cannot destroy here because it can be called in 1324 * softint. So mark the SP as DEAD and let the timer 1325 * destroy it. See key_timehandler_spd. 1326 */ 1327 sp->state = IPSEC_SPSTATE_DEAD; 1328 } 1329 } 1330 1331 /* set policy and ipsec request if present. */ 1332 static int 1333 ipsec_set_policy( 1334 struct secpolicy **policy, 1335 int optname, 1336 const void *request, 1337 size_t len, 1338 kauth_cred_t cred 1339 ) 1340 { 1341 const struct sadb_x_policy *xpl; 1342 struct secpolicy *newsp = NULL, *oldsp; 1343 int error; 1344 1345 KASSERT(!cpu_softintr_p()); 1346 1347 /* sanity check. */ 1348 if (policy == NULL || *policy == NULL || request == NULL) 1349 return EINVAL; 1350 if (len < sizeof(*xpl)) 1351 return EINVAL; 1352 xpl = (const struct sadb_x_policy *)request; 1353 1354 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1355 kdebug_sadb_xpolicy("set passed policy", request); 1356 } 1357 1358 /* check policy type */ 1359 /* ipsec_set_policy() accepts IPSEC, ENTRUST and BYPASS. */ 1360 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 1361 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1362 return EINVAL; 1363 1364 /* check privileged socket */ 1365 if (xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1366 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPSEC, 1367 KAUTH_REQ_NETWORK_IPSEC_BYPASS, NULL, NULL, NULL); 1368 if (error) 1369 return (error); 1370 } 1371 1372 /* allocation new SP entry */ 1373 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1374 return error; 1375 1376 key_init_sp(newsp); 1377 newsp->created = time_uptime; 1378 /* Insert the global list for SPs for sockets */ 1379 key_socksplist_add(newsp); 1380 1381 /* clear old SP and set new SP */ 1382 oldsp = *policy; 1383 *policy = newsp; 1384 ipsec_destroy_policy(oldsp); 1385 1386 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1387 printf("%s: new policy\n", __func__); 1388 kdebug_secpolicy(newsp); 1389 } 1390 1391 return 0; 1392 } 1393 1394 static int 1395 ipsec_get_policy(struct secpolicy *policy, struct mbuf **mp) 1396 { 1397 1398 /* sanity check. */ 1399 if (policy == NULL || mp == NULL) 1400 return EINVAL; 1401 1402 *mp = key_sp2msg(policy, M_NOWAIT); 1403 if (!*mp) { 1404 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1405 return ENOBUFS; 1406 } 1407 1408 (*mp)->m_type = MT_DATA; 1409 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1410 kdebug_mbuf(__func__, *mp); 1411 } 1412 1413 return 0; 1414 } 1415 1416 int 1417 ipsec4_set_policy(struct inpcb *inp, int optname, const void *request, 1418 size_t len, kauth_cred_t cred) 1419 { 1420 const struct sadb_x_policy *xpl; 1421 struct secpolicy **policy; 1422 1423 KASSERT(!cpu_softintr_p()); 1424 KASSERT(inp != NULL); 1425 KASSERT(inp_locked(inp)); 1426 KASSERT(request != NULL); 1427 1428 if (len < sizeof(*xpl)) 1429 return EINVAL; 1430 xpl = (const struct sadb_x_policy *)request; 1431 1432 KASSERT(inp->inp_sp != NULL); 1433 1434 /* select direction */ 1435 switch (xpl->sadb_x_policy_dir) { 1436 case IPSEC_DIR_INBOUND: 1437 policy = &inp->inp_sp->sp_in; 1438 break; 1439 case IPSEC_DIR_OUTBOUND: 1440 policy = &inp->inp_sp->sp_out; 1441 break; 1442 default: 1443 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1444 xpl->sadb_x_policy_dir); 1445 return EINVAL; 1446 } 1447 1448 return ipsec_set_policy(policy, optname, request, len, cred); 1449 } 1450 1451 int 1452 ipsec4_get_policy(struct inpcb *inp, const void *request, size_t len, 1453 struct mbuf **mp) 1454 { 1455 const struct sadb_x_policy *xpl; 1456 struct secpolicy *policy; 1457 1458 /* sanity check. */ 1459 if (inp == NULL || request == NULL || mp == NULL) 1460 return EINVAL; 1461 KASSERT(inp->inp_sp != NULL); 1462 if (len < sizeof(*xpl)) 1463 return EINVAL; 1464 xpl = (const struct sadb_x_policy *)request; 1465 1466 /* select direction */ 1467 switch (xpl->sadb_x_policy_dir) { 1468 case IPSEC_DIR_INBOUND: 1469 policy = inp->inp_sp->sp_in; 1470 break; 1471 case IPSEC_DIR_OUTBOUND: 1472 policy = inp->inp_sp->sp_out; 1473 break; 1474 default: 1475 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1476 xpl->sadb_x_policy_dir); 1477 return EINVAL; 1478 } 1479 1480 return ipsec_get_policy(policy, mp); 1481 } 1482 1483 /* delete policy in PCB */ 1484 int 1485 ipsec4_delete_pcbpolicy(struct inpcb *inp) 1486 { 1487 1488 KASSERT(inp != NULL); 1489 1490 if (inp->inp_sp == NULL) 1491 return 0; 1492 1493 if (inp->inp_sp->sp_in != NULL) 1494 ipsec_destroy_policy(inp->inp_sp->sp_in); 1495 1496 if (inp->inp_sp->sp_out != NULL) 1497 ipsec_destroy_policy(inp->inp_sp->sp_out); 1498 1499 ipsec_invalpcbcache(inp->inp_sp, IPSEC_DIR_ANY); 1500 1501 ipsec_delpcbpolicy(inp->inp_sp); 1502 inp->inp_sp = NULL; 1503 1504 return 0; 1505 } 1506 1507 #ifdef INET6 1508 int 1509 ipsec6_set_policy(struct in6pcb *in6p, int optname, const void *request, 1510 size_t len, kauth_cred_t cred) 1511 { 1512 const struct sadb_x_policy *xpl; 1513 struct secpolicy **policy; 1514 1515 KASSERT(!cpu_softintr_p()); 1516 KASSERT(in6p_locked(in6p)); 1517 1518 /* sanity check. */ 1519 if (in6p == NULL || request == NULL) 1520 return EINVAL; 1521 if (len < sizeof(*xpl)) 1522 return EINVAL; 1523 xpl = (const struct sadb_x_policy *)request; 1524 1525 /* select direction */ 1526 switch (xpl->sadb_x_policy_dir) { 1527 case IPSEC_DIR_INBOUND: 1528 policy = &in6p->in6p_sp->sp_in; 1529 break; 1530 case IPSEC_DIR_OUTBOUND: 1531 policy = &in6p->in6p_sp->sp_out; 1532 break; 1533 default: 1534 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1535 xpl->sadb_x_policy_dir); 1536 return EINVAL; 1537 } 1538 1539 return ipsec_set_policy(policy, optname, request, len, cred); 1540 } 1541 1542 int 1543 ipsec6_get_policy(struct in6pcb *in6p, const void *request, size_t len, 1544 struct mbuf **mp) 1545 { 1546 const struct sadb_x_policy *xpl; 1547 struct secpolicy *policy; 1548 1549 /* sanity check. */ 1550 if (in6p == NULL || request == NULL || mp == NULL) 1551 return EINVAL; 1552 KASSERT(in6p->in6p_sp != NULL); 1553 if (len < sizeof(*xpl)) 1554 return EINVAL; 1555 xpl = (const struct sadb_x_policy *)request; 1556 1557 /* select direction */ 1558 switch (xpl->sadb_x_policy_dir) { 1559 case IPSEC_DIR_INBOUND: 1560 policy = in6p->in6p_sp->sp_in; 1561 break; 1562 case IPSEC_DIR_OUTBOUND: 1563 policy = in6p->in6p_sp->sp_out; 1564 break; 1565 default: 1566 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1567 xpl->sadb_x_policy_dir); 1568 return EINVAL; 1569 } 1570 1571 return ipsec_get_policy(policy, mp); 1572 } 1573 1574 int 1575 ipsec6_delete_pcbpolicy(struct in6pcb *in6p) 1576 { 1577 1578 KASSERT(in6p != NULL); 1579 1580 if (in6p->in6p_sp == NULL) 1581 return 0; 1582 1583 if (in6p->in6p_sp->sp_in != NULL) 1584 ipsec_destroy_policy(in6p->in6p_sp->sp_in); 1585 1586 if (in6p->in6p_sp->sp_out != NULL) 1587 ipsec_destroy_policy(in6p->in6p_sp->sp_out); 1588 1589 ipsec_invalpcbcache(in6p->in6p_sp, IPSEC_DIR_ANY); 1590 1591 ipsec_delpcbpolicy(in6p->in6p_sp); 1592 in6p->in6p_sp = NULL; 1593 1594 return 0; 1595 } 1596 #endif 1597 1598 /* 1599 * return current level. 1600 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1601 */ 1602 u_int 1603 ipsec_get_reqlevel(const struct ipsecrequest *isr) 1604 { 1605 u_int level = 0; 1606 u_int esp_trans_deflev, esp_net_deflev; 1607 u_int ah_trans_deflev, ah_net_deflev; 1608 1609 KASSERT(isr != NULL); 1610 KASSERT(isr->sp != NULL); 1611 KASSERTMSG( 1612 isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1613 "af family mismatch, src %u, dst %u", 1614 isr->sp->spidx.src.sa.sa_family, isr->sp->spidx.dst.sa.sa_family); 1615 1616 /* XXX note that we have ipseclog() expanded here - code sync issue */ 1617 #define IPSEC_CHECK_DEFAULT(lev) \ 1618 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1619 && (lev) != IPSEC_LEVEL_UNIQUE) ? \ 1620 (ipsec_debug ? log(LOG_INFO, "fixed system default level " #lev \ 1621 ":%d->%d\n", (lev), IPSEC_LEVEL_REQUIRE) : (void)0), \ 1622 (lev) = IPSEC_LEVEL_REQUIRE, (lev) \ 1623 : (lev)) 1624 1625 /* set default level */ 1626 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1627 #ifdef INET 1628 case AF_INET: 1629 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_trans_deflev); 1630 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_net_deflev); 1631 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_trans_deflev); 1632 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_net_deflev); 1633 break; 1634 #endif 1635 #ifdef INET6 1636 case AF_INET6: 1637 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_trans_deflev); 1638 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_net_deflev); 1639 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_trans_deflev); 1640 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_net_deflev); 1641 break; 1642 #endif /* INET6 */ 1643 default: 1644 panic("%s: unknown af %u", __func__, 1645 isr->sp->spidx.src.sa.sa_family); 1646 } 1647 1648 #undef IPSEC_CHECK_DEFAULT 1649 1650 /* set level */ 1651 switch (isr->level) { 1652 case IPSEC_LEVEL_DEFAULT: 1653 switch (isr->saidx.proto) { 1654 case IPPROTO_ESP: 1655 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1656 level = esp_net_deflev; 1657 else 1658 level = esp_trans_deflev; 1659 break; 1660 case IPPROTO_AH: 1661 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1662 level = ah_net_deflev; 1663 else 1664 level = ah_trans_deflev; 1665 break; 1666 case IPPROTO_IPCOMP: 1667 /* 1668 * we don't really care, as IPcomp document says that 1669 * we shouldn't compress small packets 1670 */ 1671 level = IPSEC_LEVEL_USE; 1672 break; 1673 default: 1674 panic("%s: Illegal protocol defined %u", __func__, 1675 isr->saidx.proto); 1676 } 1677 break; 1678 1679 case IPSEC_LEVEL_USE: 1680 case IPSEC_LEVEL_REQUIRE: 1681 level = isr->level; 1682 break; 1683 case IPSEC_LEVEL_UNIQUE: 1684 level = IPSEC_LEVEL_REQUIRE; 1685 break; 1686 1687 default: 1688 panic("%s: Illegal IPsec level %u", __func__, isr->level); 1689 } 1690 1691 return level; 1692 } 1693 1694 /* 1695 * Check security policy requirements against the actual 1696 * packet contents. Return one if the packet should be 1697 * reject as "invalid"; otherwiser return zero to have the 1698 * packet treated as "valid". 1699 * 1700 * OUT: 1701 * 0: valid 1702 * 1: invalid 1703 */ 1704 int 1705 ipsec_in_reject(const struct secpolicy *sp, const struct mbuf *m) 1706 { 1707 struct ipsecrequest *isr; 1708 1709 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1710 printf("%s: using SP\n", __func__); 1711 kdebug_secpolicy(sp); 1712 } 1713 1714 /* check policy */ 1715 switch (sp->policy) { 1716 case IPSEC_POLICY_DISCARD: 1717 return 1; 1718 case IPSEC_POLICY_BYPASS: 1719 case IPSEC_POLICY_NONE: 1720 return 0; 1721 } 1722 1723 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1724 "invalid policy %u", sp->policy); 1725 1726 /* XXX should compare policy against ipsec header history */ 1727 1728 for (isr = sp->req; isr != NULL; isr = isr->next) { 1729 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1730 continue; 1731 switch (isr->saidx.proto) { 1732 case IPPROTO_ESP: 1733 if ((m->m_flags & M_DECRYPTED) == 0) { 1734 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1735 "ESP m_flags:%x\n", m->m_flags); 1736 return 1; 1737 } 1738 break; 1739 case IPPROTO_AH: 1740 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1741 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1742 "AH m_flags:%x\n", m->m_flags); 1743 return 1; 1744 } 1745 break; 1746 case IPPROTO_IPCOMP: 1747 /* 1748 * we don't really care, as IPcomp document 1749 * says that we shouldn't compress small 1750 * packets, IPComp policy should always be 1751 * treated as being in "use" level. 1752 */ 1753 break; 1754 } 1755 } 1756 return 0; /* valid */ 1757 } 1758 1759 /* 1760 * Check AH/ESP integrity. 1761 * This function is called from tcp_input(), udp_input(), 1762 * and {ah,esp}4_input for tunnel mode 1763 */ 1764 int 1765 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1766 { 1767 struct secpolicy *sp; 1768 int error; 1769 int result; 1770 1771 KASSERT(m != NULL); 1772 1773 /* get SP for this packet. 1774 * When we are called from ip_forward(), we call 1775 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1776 */ 1777 if (inp == NULL) 1778 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1779 else 1780 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1781 (struct inpcb_hdr *)inp, &error); 1782 1783 if (sp != NULL) { 1784 result = ipsec_in_reject(sp, m); 1785 if (result) 1786 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1787 KEY_SP_UNREF(&sp); 1788 } else { 1789 result = 0; /* XXX should be panic ? 1790 * -> No, there may be error. */ 1791 } 1792 return result; 1793 } 1794 1795 1796 #ifdef INET6 1797 /* 1798 * Check AH/ESP integrity. 1799 * This function is called from tcp6_input(), udp6_input(), 1800 * and {ah,esp}6_input for tunnel mode 1801 */ 1802 int 1803 ipsec6_in_reject(struct mbuf *m, struct in6pcb *in6p) 1804 { 1805 struct secpolicy *sp = NULL; 1806 int error; 1807 int result; 1808 1809 KASSERT(m != NULL); 1810 1811 /* get SP for this packet. 1812 * When we are called from ip_forward(), we call 1813 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1814 */ 1815 if (in6p == NULL) 1816 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1817 else 1818 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1819 (struct inpcb_hdr *)in6p, 1820 &error); 1821 1822 if (sp != NULL) { 1823 result = ipsec_in_reject(sp, m); 1824 if (result) 1825 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1826 KEY_SP_UNREF(&sp); 1827 } else { 1828 result = 0; 1829 } 1830 return result; 1831 } 1832 #endif 1833 1834 /* 1835 * compute the byte size to be occupied by IPsec header. 1836 * in case it is tunneled, it includes the size of outer IP header. 1837 * NOTE: SP passed is free in this function. 1838 */ 1839 static size_t 1840 ipsec_hdrsiz(const struct secpolicy *sp, const struct mbuf *m) 1841 { 1842 struct ipsecrequest *isr; 1843 size_t siz; 1844 1845 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1846 printf("%s: using SP\n", __func__); 1847 kdebug_secpolicy(sp); 1848 } 1849 1850 switch (sp->policy) { 1851 case IPSEC_POLICY_DISCARD: 1852 case IPSEC_POLICY_BYPASS: 1853 case IPSEC_POLICY_NONE: 1854 return 0; 1855 } 1856 1857 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1858 "invalid policy %u", sp->policy); 1859 1860 siz = 0; 1861 for (isr = sp->req; isr != NULL; isr = isr->next) { 1862 size_t clen = 0; 1863 struct secasvar *sav; 1864 1865 switch (isr->saidx.proto) { 1866 case IPPROTO_ESP: 1867 sav = ipsec_lookup_sa(isr, m); 1868 if (sav != NULL) { 1869 clen = esp_hdrsiz(sav); 1870 KEY_SA_UNREF(&sav); 1871 } else 1872 clen = esp_hdrsiz(NULL); 1873 break; 1874 case IPPROTO_AH: 1875 sav = ipsec_lookup_sa(isr, m); 1876 if (sav != NULL) { 1877 clen = ah_hdrsiz(sav); 1878 KEY_SA_UNREF(&sav); 1879 } else 1880 clen = ah_hdrsiz(NULL); 1881 break; 1882 case IPPROTO_IPCOMP: 1883 clen = sizeof(struct ipcomp); 1884 break; 1885 } 1886 1887 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1888 switch (isr->saidx.dst.sa.sa_family) { 1889 case AF_INET: 1890 clen += sizeof(struct ip); 1891 break; 1892 #ifdef INET6 1893 case AF_INET6: 1894 clen += sizeof(struct ip6_hdr); 1895 break; 1896 #endif 1897 default: 1898 IPSECLOG(LOG_ERR, "unknown AF %d in " 1899 "IPsec tunnel SA\n", 1900 ((const struct sockaddr *)&isr->saidx.dst) 1901 ->sa_family); 1902 break; 1903 } 1904 } 1905 siz += clen; 1906 } 1907 1908 return siz; 1909 } 1910 1911 /* This function is called from ip_forward() and ipsec4_hdrsize_tcp(). */ 1912 size_t 1913 ipsec4_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1914 { 1915 struct secpolicy *sp; 1916 int error; 1917 size_t size; 1918 1919 KASSERT(m != NULL); 1920 KASSERTMSG(inp == NULL || inp->inp_socket != NULL, "socket w/o inpcb"); 1921 1922 /* get SP for this packet. 1923 * When we are called from ip_forward(), we call 1924 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1925 */ 1926 if (inp == NULL) 1927 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1928 else 1929 sp = ipsec_getpolicybysock(m, dir, 1930 (struct inpcb_hdr *)inp, &error); 1931 1932 if (sp != NULL) { 1933 size = ipsec_hdrsiz(sp, m); 1934 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%lu.\n", 1935 (unsigned long)size); 1936 1937 KEY_SP_UNREF(&sp); 1938 } else { 1939 size = 0; /* XXX should be panic ? */ 1940 } 1941 return size; 1942 } 1943 1944 #ifdef INET6 1945 /* This function is called from ipsec6_hdrsize_tcp(), 1946 * and maybe from ip6_forward.() 1947 */ 1948 size_t 1949 ipsec6_hdrsiz(struct mbuf *m, u_int dir, struct in6pcb *in6p) 1950 { 1951 struct secpolicy *sp; 1952 int error; 1953 size_t size; 1954 1955 KASSERT(m != NULL); 1956 KASSERTMSG(in6p == NULL || in6p->in6p_socket != NULL, 1957 "socket w/o inpcb"); 1958 1959 /* get SP for this packet */ 1960 /* XXX Is it right to call with IP_FORWARDING. */ 1961 if (in6p == NULL) 1962 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1963 else 1964 sp = ipsec_getpolicybysock(m, dir, 1965 (struct inpcb_hdr *)in6p, 1966 &error); 1967 1968 if (sp == NULL) 1969 return 0; 1970 size = ipsec_hdrsiz(sp, m); 1971 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%zu.\n", size); 1972 KEY_SP_UNREF(&sp); 1973 1974 return size; 1975 } 1976 #endif /*INET6*/ 1977 1978 /* 1979 * Check the variable replay window. 1980 * ipsec_chkreplay() performs replay check before ICV verification. 1981 * ipsec_updatereplay() updates replay bitmap. This must be called after 1982 * ICV verification (it also performs replay check, which is usually done 1983 * beforehand). 1984 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1985 * 1986 * based on RFC 2401. 1987 */ 1988 int 1989 ipsec_chkreplay(u_int32_t seq, const struct secasvar *sav) 1990 { 1991 const struct secreplay *replay; 1992 u_int32_t diff; 1993 int fr; 1994 u_int32_t wsizeb; /* constant: bits of window size */ 1995 int frlast; /* constant: last frame */ 1996 1997 IPSEC_SPLASSERT_SOFTNET(__func__); 1998 1999 KASSERT(sav != NULL); 2000 KASSERT(sav->replay != NULL); 2001 2002 replay = sav->replay; 2003 2004 if (replay->wsize == 0) 2005 return 1; /* no need to check replay. */ 2006 2007 /* constant */ 2008 frlast = replay->wsize - 1; 2009 wsizeb = replay->wsize << 3; 2010 2011 /* sequence number of 0 is invalid */ 2012 if (seq == 0) 2013 return 0; 2014 2015 /* first time is always okay */ 2016 if (replay->count == 0) 2017 return 1; 2018 2019 if (seq > replay->lastseq) { 2020 /* larger sequences are okay */ 2021 return 1; 2022 } else { 2023 /* seq is equal or less than lastseq. */ 2024 diff = replay->lastseq - seq; 2025 2026 /* over range to check, i.e. too old or wrapped */ 2027 if (diff >= wsizeb) 2028 return 0; 2029 2030 fr = frlast - diff / 8; 2031 2032 /* this packet already seen ? */ 2033 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2034 return 0; 2035 2036 /* out of order but good */ 2037 return 1; 2038 } 2039 } 2040 2041 /* 2042 * check replay counter whether to update or not. 2043 * OUT: 0: OK 2044 * 1: NG 2045 */ 2046 int 2047 ipsec_updatereplay(u_int32_t seq, const struct secasvar *sav) 2048 { 2049 struct secreplay *replay; 2050 u_int32_t diff; 2051 int fr; 2052 u_int32_t wsizeb; /* constant: bits of window size */ 2053 int frlast; /* constant: last frame */ 2054 2055 IPSEC_SPLASSERT_SOFTNET(__func__); 2056 2057 KASSERT(sav != NULL); 2058 KASSERT(sav->replay != NULL); 2059 2060 replay = sav->replay; 2061 2062 if (replay->wsize == 0) 2063 goto ok; /* no need to check replay. */ 2064 2065 /* constant */ 2066 frlast = replay->wsize - 1; 2067 wsizeb = replay->wsize << 3; 2068 2069 /* sequence number of 0 is invalid */ 2070 if (seq == 0) 2071 return 1; 2072 2073 /* first time */ 2074 if (replay->count == 0) { 2075 replay->lastseq = seq; 2076 memset(replay->bitmap, 0, replay->wsize); 2077 (replay->bitmap)[frlast] = 1; 2078 goto ok; 2079 } 2080 2081 if (seq > replay->lastseq) { 2082 /* seq is larger than lastseq. */ 2083 diff = seq - replay->lastseq; 2084 2085 /* new larger sequence number */ 2086 if (diff < wsizeb) { 2087 /* In window */ 2088 /* set bit for this packet */ 2089 vshiftl(replay->bitmap, diff, replay->wsize); 2090 (replay->bitmap)[frlast] |= 1; 2091 } else { 2092 /* this packet has a "way larger" */ 2093 memset(replay->bitmap, 0, replay->wsize); 2094 (replay->bitmap)[frlast] = 1; 2095 } 2096 replay->lastseq = seq; 2097 2098 /* larger is good */ 2099 } else { 2100 /* seq is equal or less than lastseq. */ 2101 diff = replay->lastseq - seq; 2102 2103 /* over range to check, i.e. too old or wrapped */ 2104 if (diff >= wsizeb) 2105 return 1; 2106 2107 fr = frlast - diff / 8; 2108 2109 /* this packet already seen ? */ 2110 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2111 return 1; 2112 2113 /* mark as seen */ 2114 (replay->bitmap)[fr] |= (1 << (diff % 8)); 2115 2116 /* out of order but good */ 2117 } 2118 2119 ok: 2120 if (replay->count == ~0) { 2121 char buf[IPSEC_LOGSASTRLEN]; 2122 2123 /* set overflow flag */ 2124 replay->overflow++; 2125 2126 /* don't increment, no more packets accepted */ 2127 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 2128 return 1; 2129 2130 IPSECLOG(LOG_WARNING, "replay counter made %d cycle. %s\n", 2131 replay->overflow, ipsec_logsastr(sav, buf, sizeof(buf))); 2132 } 2133 2134 replay->count++; 2135 2136 return 0; 2137 } 2138 2139 /* 2140 * shift variable length bunffer to left. 2141 * IN: bitmap: pointer to the buffer 2142 * nbit: the number of to shift. 2143 * wsize: buffer size (bytes). 2144 */ 2145 static void 2146 vshiftl(unsigned char *bitmap, int nbit, int wsize) 2147 { 2148 int s, j, i; 2149 unsigned char over; 2150 2151 for (j = 0; j < nbit; j += 8) { 2152 s = (nbit - j < 8) ? (nbit - j): 8; 2153 bitmap[0] <<= s; 2154 for (i = 1; i < wsize; i++) { 2155 over = (bitmap[i] >> (8 - s)); 2156 bitmap[i] <<= s; 2157 bitmap[i-1] |= over; 2158 } 2159 } 2160 2161 return; 2162 } 2163 2164 /* Return a printable string for the address. */ 2165 const char * 2166 ipsec_address(const union sockaddr_union *sa, char *buf, size_t size) 2167 { 2168 switch (sa->sa.sa_family) { 2169 #if INET 2170 case AF_INET: 2171 in_print(buf, size, &sa->sin.sin_addr); 2172 return buf; 2173 #endif /* INET */ 2174 2175 #if INET6 2176 case AF_INET6: 2177 in6_print(buf, size, &sa->sin6.sin6_addr); 2178 return buf; 2179 #endif /* INET6 */ 2180 2181 default: 2182 return "(unknown address family)"; 2183 } 2184 } 2185 2186 const char * 2187 ipsec_logsastr(const struct secasvar *sav, char *buf, size_t size) 2188 { 2189 const struct secasindex *saidx = &sav->sah->saidx; 2190 char sbuf[IPSEC_ADDRSTRLEN], dbuf[IPSEC_ADDRSTRLEN]; 2191 2192 KASSERTMSG(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 2193 "af family mismatch, src %u, dst %u", 2194 saidx->src.sa.sa_family, saidx->dst.sa.sa_family); 2195 2196 snprintf(buf, size, "SA(SPI=%u src=%s dst=%s)", 2197 (u_int32_t)ntohl(sav->spi), 2198 ipsec_address(&saidx->src, sbuf, sizeof(sbuf)), 2199 ipsec_address(&saidx->dst, dbuf, sizeof(dbuf))); 2200 2201 return buf; 2202 } 2203 2204 void 2205 ipsec_dumpmbuf(struct mbuf *m) 2206 { 2207 int totlen; 2208 int i; 2209 u_char *p; 2210 2211 totlen = 0; 2212 printf("---\n"); 2213 while (m) { 2214 p = mtod(m, u_char *); 2215 for (i = 0; i < m->m_len; i++) { 2216 printf("%02x ", p[i]); 2217 totlen++; 2218 if (totlen % 16 == 0) 2219 printf("\n"); 2220 } 2221 m = m->m_next; 2222 } 2223 if (totlen % 16 != 0) 2224 printf("\n"); 2225 printf("---\n"); 2226 } 2227 2228 #ifdef INET6 2229 struct secpolicy * 2230 ipsec6_check_policy(struct mbuf *m, struct in6pcb *in6p, 2231 int flags, int *needipsecp, int *errorp) 2232 { 2233 struct secpolicy *sp = NULL; 2234 int s; 2235 int error = 0; 2236 int needipsec = 0; 2237 2238 if (!ipsec_outdone(m)) { 2239 s = splsoftnet(); 2240 if (in6p != NULL && 2241 ipsec_pcb_skip_ipsec(in6p->in6p_sp, IPSEC_DIR_OUTBOUND)) { 2242 splx(s); 2243 goto skippolicycheck; 2244 } 2245 sp = ipsec6_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error,in6p); 2246 2247 /* 2248 * There are four return cases: 2249 * sp != NULL apply IPsec policy 2250 * sp == NULL, error == 0 no IPsec handling needed 2251 * sp == NULL, error == -EINVAL discard packet w/o error 2252 * sp == NULL, error != 0 discard packet, report error 2253 */ 2254 2255 splx(s); 2256 if (sp == NULL) { 2257 /* 2258 * Caller must check the error return to see if it needs to discard 2259 * the packet. 2260 */ 2261 needipsec = 0; 2262 } else { 2263 needipsec = 1; 2264 } 2265 } 2266 skippolicycheck:; 2267 2268 *errorp = error; 2269 *needipsecp = needipsec; 2270 return sp; 2271 } 2272 2273 int 2274 ipsec6_input(struct mbuf *m) 2275 { 2276 struct secpolicy *sp; 2277 int s, error; 2278 2279 s = splsoftnet(); 2280 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 2281 if (sp != NULL) { 2282 /* 2283 * Check security policy against packet 2284 * attributes. 2285 */ 2286 error = ipsec_in_reject(sp, m); 2287 KEY_SP_UNREF(&sp); 2288 } else { 2289 /* XXX error stat??? */ 2290 error = EINVAL; 2291 IPSECLOG(LOG_DEBUG, "no SP, packet discarded\n");/*XXX*/ 2292 } 2293 splx(s); 2294 2295 return error; 2296 } 2297 #endif /* INET6 */ 2298 2299 2300 2301 /* XXX this stuff doesn't belong here... */ 2302 2303 static struct xformsw *xforms = NULL; 2304 2305 /* 2306 * Register a transform; typically at system startup. 2307 */ 2308 void 2309 xform_register(struct xformsw *xsp) 2310 { 2311 xsp->xf_next = xforms; 2312 xforms = xsp; 2313 } 2314 2315 /* 2316 * Initialize transform support in an sav. 2317 */ 2318 int 2319 xform_init(struct secasvar *sav, int xftype) 2320 { 2321 struct xformsw *xsp; 2322 2323 if (sav->tdb_xform != NULL) /* previously initialized */ 2324 return 0; 2325 for (xsp = xforms; xsp; xsp = xsp->xf_next) 2326 if (xsp->xf_type == xftype) 2327 return (*xsp->xf_init)(sav, xsp); 2328 2329 IPSECLOG(LOG_DEBUG, "no match for xform type %d\n", xftype); 2330 return EINVAL; 2331 } 2332 2333 void 2334 nat_t_ports_get(struct mbuf *m, u_int16_t *dport, u_int16_t *sport) { 2335 struct m_tag *tag; 2336 2337 if ((tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL))) { 2338 *sport = ((u_int16_t *)(tag + 1))[0]; 2339 *dport = ((u_int16_t *)(tag + 1))[1]; 2340 } else 2341 *sport = *dport = 0; 2342 } 2343 2344 /* 2345 * XXXJRT This should be done as a protosw init call. 2346 */ 2347 void 2348 ipsec_attach(void) 2349 { 2350 2351 ipsec_output_init(); 2352 2353 ipsecstat_percpu = percpu_alloc(sizeof(uint64_t) * IPSEC_NSTATS); 2354 2355 sysctl_net_inet_ipsec_setup(NULL); 2356 #ifdef INET6 2357 sysctl_net_inet6_ipsec6_setup(NULL); 2358 #endif 2359 2360 ah_attach(); 2361 esp_attach(); 2362 ipcomp_attach(); 2363 ipe4_attach(); 2364 #ifdef TCP_SIGNATURE 2365 tcpsignature_attach(); 2366 #endif 2367 } 2368
Indexes created Tue Sep 30 10:09:55 GMT 2025