ipsec.c revision 1.118
1 /* $NetBSD: ipsec.c,v 1.118 2017/08/10 06:11:24 ozaki-r 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 1.118 2017/08/10 06:11:24 ozaki-r 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 #include <net/net_osdep.h> 107 108 int ipsec_used = 0; 109 int ipsec_enabled = 1; 110 111 #ifdef IPSEC_DEBUG 112 int ipsec_debug = 1; 113 114 /* 115 * When set to 1, IPsec will send packets with the same sequence number. 116 * This allows to verify if the other side has proper replay attacks detection. 117 */ 118 int ipsec_replay = 0; 119 120 /* 121 * When set 1, IPsec will send packets with corrupted HMAC. 122 * This allows to verify if the other side properly detects modified packets. 123 */ 124 int ipsec_integrity = 0; 125 #else 126 int ipsec_debug = 0; 127 #endif 128 129 percpu_t *ipsecstat_percpu; 130 int ip4_ah_offsetmask = 0; /* maybe IP_DF? */ 131 int ip4_ipsec_dfbit = 2; /* DF bit on encap. 0: clear 1: set 2: copy */ 132 int ip4_esp_trans_deflev = IPSEC_LEVEL_USE; 133 int ip4_esp_net_deflev = IPSEC_LEVEL_USE; 134 int ip4_ah_trans_deflev = IPSEC_LEVEL_USE; 135 int ip4_ah_net_deflev = IPSEC_LEVEL_USE; 136 struct secpolicy ip4_def_policy; 137 int ip4_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 138 int ip4_esp_randpad = -1; 139 140 u_int ipsec_spdgen = 1; /* SPD generation # */ 141 142 static struct secpolicy *ipsec_checkpcbcache (struct mbuf *, 143 struct inpcbpolicy *, int); 144 static int ipsec_fillpcbcache (struct inpcbpolicy *, struct mbuf *, 145 struct secpolicy *, int); 146 static int ipsec_invalpcbcache (struct inpcbpolicy *, int); 147 148 /* 149 * Crypto support requirements: 150 * 151 * 1 require hardware support 152 * -1 require software support 153 * 0 take anything 154 */ 155 int crypto_support = 0; 156 157 static struct secpolicy *ipsec_getpolicybysock(struct mbuf *, u_int, 158 struct inpcb_hdr *, int *); 159 160 #ifdef __FreeBSD__ 161 /* net.inet.ipsec */ 162 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_ESP_RANDPAD, 163 esp_randpad, CTLFLAG_RW, &ip4_esp_randpad, 0, ""); 164 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, 165 crypto_support, CTLFLAG_RW, &crypto_support,0, ""); 166 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_replay, CTLFLAG_RW, &ipsec_replay, 0, 167 "Emulate replay attack"); 168 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_integrity, CTLFLAG_RW, 169 &ipsec_integrity, 0, "Emulate man-in-the-middle attack"); 170 #endif /* __FreeBSD__ */ 171 172 #ifdef INET6 173 int ip6_esp_trans_deflev = IPSEC_LEVEL_USE; 174 int ip6_esp_net_deflev = IPSEC_LEVEL_USE; 175 int ip6_ah_trans_deflev = IPSEC_LEVEL_USE; 176 int ip6_ah_net_deflev = IPSEC_LEVEL_USE; 177 struct secpolicy ip6_def_policy; 178 int ip6_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 179 int ip6_esp_randpad = -1; 180 181 182 #ifdef __FreeBSD__ 183 /* net.inet6.ipsec6 */ 184 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_ESP_RANDPAD, 185 esp_randpad, CTLFLAG_RW, &ip6_esp_randpad, 0, ""); 186 #endif /* __FreeBSD__ */ 187 #endif /* INET6 */ 188 189 static int ipsec4_setspidx_inpcb (struct mbuf *, struct inpcb *); 190 #ifdef INET6 191 static int ipsec6_setspidx_in6pcb (struct mbuf *, struct in6pcb *); 192 #endif 193 static int ipsec_setspidx (struct mbuf *, struct secpolicyindex *, int); 194 static void ipsec4_get_ulp (struct mbuf *m, struct secpolicyindex *, int); 195 static int ipsec4_setspidx_ipaddr (struct mbuf *, struct secpolicyindex *); 196 #ifdef INET6 197 static void ipsec6_get_ulp (struct mbuf *m, struct secpolicyindex *, int); 198 static int ipsec6_setspidx_ipaddr (struct mbuf *, struct secpolicyindex *); 199 #endif 200 static void ipsec_delpcbpolicy (struct inpcbpolicy *); 201 #if 0 /* unused */ 202 static struct secpolicy *ipsec_deepcopy_policy (const struct secpolicy *); 203 #endif 204 static int ipsec_set_policy (struct secpolicy **, int, const void *, size_t, 205 kauth_cred_t); 206 static int ipsec_get_policy (struct secpolicy *, struct mbuf **); 207 static void ipsec_destroy_policy(struct secpolicy *); 208 static void vshiftl (unsigned char *, int, int); 209 static size_t ipsec_hdrsiz (const struct secpolicy *); 210 211 /* 212 * Try to validate and use cached policy on a PCB. 213 */ 214 static struct secpolicy * 215 ipsec_checkpcbcache(struct mbuf *m, struct inpcbpolicy *pcbsp, int dir) 216 { 217 struct secpolicyindex spidx; 218 struct secpolicy *sp = NULL; 219 int s; 220 221 KASSERT(IPSEC_DIR_IS_VALID(dir)); 222 KASSERT(pcbsp != NULL); 223 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 224 KASSERT(inph_locked(pcbsp->sp_inph)); 225 226 /* 227 * Checking the generation and sp->state and taking a reference to an SP 228 * must be in a critical section of pserialize. See key_unlink_sp. 229 */ 230 s = pserialize_read_enter(); 231 /* SPD table change invalidate all the caches. */ 232 if (ipsec_spdgen != pcbsp->sp_cache[dir].cachegen) { 233 ipsec_invalpcbcache(pcbsp, dir); 234 goto out; 235 } 236 sp = pcbsp->sp_cache[dir].cachesp; 237 if (sp == NULL) 238 goto out; 239 if (sp->state != IPSEC_SPSTATE_ALIVE) { 240 sp = NULL; 241 ipsec_invalpcbcache(pcbsp, dir); 242 goto out; 243 } 244 if ((pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) == 0) { 245 /* NB: assume ipsec_setspidx never sleep */ 246 if (ipsec_setspidx(m, &spidx, 1) != 0) { 247 sp = NULL; 248 goto out; 249 } 250 251 /* 252 * We have to make an exact match here since the cached rule 253 * might have lower priority than a rule that would otherwise 254 * have matched the packet. 255 */ 256 if (memcmp(&pcbsp->sp_cache[dir].cacheidx, &spidx, 257 sizeof(spidx))) { 258 sp = NULL; 259 goto out; 260 } 261 } else { 262 /* 263 * The pcb is connected, and the L4 code is sure that: 264 * - outgoing side uses inp_[lf]addr 265 * - incoming side looks up policy after inpcb lookup 266 * and address pair is know to be stable. We do not need 267 * to generate spidx again, nor check the address match again. 268 * 269 * For IPv4/v6 SOCK_STREAM sockets, this assumptions holds 270 * and there are calls to ipsec_pcbconn() from in_pcbconnect(). 271 */ 272 } 273 274 sp->lastused = time_second; 275 KEY_SP_REF(sp); 276 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 277 "DP cause refcnt++:%d SP:%p\n", 278 key_sp_refcnt(sp), pcbsp->sp_cache[dir].cachesp); 279 out: 280 pserialize_read_exit(s); 281 return sp; 282 } 283 284 static int 285 ipsec_fillpcbcache(struct inpcbpolicy *pcbsp, struct mbuf *m, 286 struct secpolicy *sp, int dir) 287 { 288 289 KASSERT(IPSEC_DIR_IS_INOROUT(dir)); 290 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 291 KASSERT(inph_locked(pcbsp->sp_inph)); 292 293 pcbsp->sp_cache[dir].cachesp = NULL; 294 pcbsp->sp_cache[dir].cachehint = IPSEC_PCBHINT_UNKNOWN; 295 if (ipsec_setspidx(m, &pcbsp->sp_cache[dir].cacheidx, 1) != 0) { 296 return EINVAL; 297 } 298 pcbsp->sp_cache[dir].cachesp = sp; 299 if (pcbsp->sp_cache[dir].cachesp) { 300 /* 301 * If the PCB is connected, we can remember a hint to 302 * possibly short-circuit IPsec processing in other places. 303 */ 304 if (pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) { 305 switch (pcbsp->sp_cache[dir].cachesp->policy) { 306 case IPSEC_POLICY_NONE: 307 case IPSEC_POLICY_BYPASS: 308 pcbsp->sp_cache[dir].cachehint = 309 IPSEC_PCBHINT_NO; 310 break; 311 default: 312 pcbsp->sp_cache[dir].cachehint = 313 IPSEC_PCBHINT_YES; 314 } 315 } 316 } 317 pcbsp->sp_cache[dir].cachegen = ipsec_spdgen; 318 319 return 0; 320 } 321 322 static int 323 ipsec_invalpcbcache(struct inpcbpolicy *pcbsp, int dir) 324 { 325 int i; 326 327 KASSERT(inph_locked(pcbsp->sp_inph)); 328 329 for (i = IPSEC_DIR_INBOUND; i <= IPSEC_DIR_OUTBOUND; i++) { 330 if (dir != IPSEC_DIR_ANY && i != dir) 331 continue; 332 pcbsp->sp_cache[i].cachesp = NULL; 333 pcbsp->sp_cache[i].cachehint = IPSEC_PCBHINT_UNKNOWN; 334 pcbsp->sp_cache[i].cachegen = 0; 335 memset(&pcbsp->sp_cache[i].cacheidx, 0, 336 sizeof(pcbsp->sp_cache[i].cacheidx)); 337 } 338 return 0; 339 } 340 341 void 342 ipsec_pcbconn(struct inpcbpolicy *pcbsp) 343 { 344 345 KASSERT(inph_locked(pcbsp->sp_inph)); 346 347 pcbsp->sp_cacheflags |= IPSEC_PCBSP_CONNECTED; 348 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 349 } 350 351 void 352 ipsec_pcbdisconn(struct inpcbpolicy *pcbsp) 353 { 354 355 KASSERT(inph_locked(pcbsp->sp_inph)); 356 357 pcbsp->sp_cacheflags &= ~IPSEC_PCBSP_CONNECTED; 358 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 359 } 360 361 void 362 ipsec_invalpcbcacheall(void) 363 { 364 365 if (ipsec_spdgen == UINT_MAX) 366 ipsec_spdgen = 1; 367 else 368 ipsec_spdgen++; 369 } 370 371 /* 372 * Return a held reference to the default SP. 373 */ 374 static struct secpolicy * 375 key_get_default_sp(int af, const char *where, int tag) 376 { 377 struct secpolicy *sp; 378 379 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP from %s:%u\n", where, tag); 380 381 switch(af) { 382 case AF_INET: 383 sp = &ip4_def_policy; 384 break; 385 #ifdef INET6 386 case AF_INET6: 387 sp = &ip6_def_policy; 388 break; 389 #endif 390 default: 391 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 392 "unexpected protocol family %u\n", af); 393 return NULL; 394 } 395 396 if (sp->policy != IPSEC_POLICY_DISCARD && 397 sp->policy != IPSEC_POLICY_NONE) { 398 IPSECLOG(LOG_INFO, "fixed system default policy: %d->%d\n", 399 sp->policy, IPSEC_POLICY_NONE); 400 sp->policy = IPSEC_POLICY_NONE; 401 } 402 KEY_SP_REF(sp); 403 404 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP returns SP:%p (%u)\n", 405 sp, key_sp_refcnt(sp)); 406 return sp; 407 } 408 #define KEY_GET_DEFAULT_SP(af) \ 409 key_get_default_sp((af), __func__, __LINE__) 410 411 /* 412 * For OUTBOUND packet having a socket. Searching SPD for packet, 413 * and return a pointer to SP. 414 * OUT: NULL: no apropreate SP found, the following value is set to error. 415 * 0 : bypass 416 * EACCES : discard packet. 417 * ENOENT : ipsec_acquire() in progress, maybe. 418 * others : error occurred. 419 * others: a pointer to SP 420 * 421 * NOTE: IPv6 mapped address concern is implemented here. 422 */ 423 static struct secpolicy * 424 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb_hdr *inph, 425 int *error) 426 { 427 struct inpcbpolicy *pcbsp = NULL; 428 struct secpolicy *currsp = NULL; /* policy on socket */ 429 struct secpolicy *sp; 430 int af; 431 432 KASSERT(m != NULL); 433 KASSERT(inph != NULL); 434 KASSERT(error != NULL); 435 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 436 437 KASSERT(inph->inph_socket != NULL); 438 KASSERT(inph_locked(inph)); 439 440 /* XXX FIXME inpcb/in6pcb vs socket*/ 441 af = inph->inph_af; 442 KASSERTMSG(af == AF_INET || af == AF_INET6, 443 "unexpected protocol family %u", af); 444 445 KASSERT(inph->inph_sp != NULL); 446 /* If we have a cached entry, and if it is still valid, use it. */ 447 IPSEC_STATINC(IPSEC_STAT_SPDCACHELOOKUP); 448 currsp = ipsec_checkpcbcache(m, inph->inph_sp, dir); 449 if (currsp) { 450 *error = 0; 451 return currsp; 452 } 453 IPSEC_STATINC(IPSEC_STAT_SPDCACHEMISS); 454 455 switch (af) { 456 case AF_INET: { 457 struct inpcb *in4p = (struct inpcb *)inph; 458 /* set spidx in pcb */ 459 *error = ipsec4_setspidx_inpcb(m, in4p); 460 pcbsp = in4p->inp_sp; 461 break; 462 } 463 464 #if defined(INET6) 465 case AF_INET6: { 466 struct in6pcb *in6p = (struct in6pcb *)inph; 467 /* set spidx in pcb */ 468 *error = ipsec6_setspidx_in6pcb(m, in6p); 469 pcbsp = in6p->in6p_sp; 470 break; 471 } 472 #endif 473 default: 474 *error = EPFNOSUPPORT; 475 break; 476 } 477 if (*error) 478 return NULL; 479 480 KASSERT(pcbsp != NULL); 481 switch (dir) { 482 case IPSEC_DIR_INBOUND: 483 currsp = pcbsp->sp_in; 484 break; 485 case IPSEC_DIR_OUTBOUND: 486 currsp = pcbsp->sp_out; 487 break; 488 } 489 KASSERT(currsp != NULL); 490 491 if (pcbsp->priv) { /* when privilieged socket */ 492 switch (currsp->policy) { 493 case IPSEC_POLICY_BYPASS: 494 case IPSEC_POLICY_IPSEC: 495 KEY_SP_REF(currsp); 496 sp = currsp; 497 break; 498 499 case IPSEC_POLICY_ENTRUST: 500 /* look for a policy in SPD */ 501 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 502 if (sp == NULL) /* no SP found */ 503 sp = KEY_GET_DEFAULT_SP(af); 504 break; 505 506 default: 507 IPSECLOG(LOG_ERR, "Invalid policy for PCB %d\n", 508 currsp->policy); 509 *error = EINVAL; 510 return NULL; 511 } 512 } else { /* unpriv, SPD has policy */ 513 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 514 if (sp == NULL) { /* no SP found */ 515 switch (currsp->policy) { 516 case IPSEC_POLICY_BYPASS: 517 IPSECLOG(LOG_ERR, "Illegal policy for " 518 "non-priviliged defined %d\n", 519 currsp->policy); 520 *error = EINVAL; 521 return NULL; 522 523 case IPSEC_POLICY_ENTRUST: 524 sp = KEY_GET_DEFAULT_SP(af); 525 break; 526 527 case IPSEC_POLICY_IPSEC: 528 KEY_SP_REF(currsp); 529 sp = currsp; 530 break; 531 532 default: 533 IPSECLOG(LOG_ERR, "Invalid policy for " 534 "PCB %d\n", currsp->policy); 535 *error = EINVAL; 536 return NULL; 537 } 538 } 539 } 540 KASSERTMSG(sp != NULL, "null SP (priv %u policy %u", pcbsp->priv, 541 currsp->policy); 542 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 543 "DP (priv %u policy %u) allocates SP:%p (refcnt %u)\n", 544 pcbsp->priv, currsp->policy, sp, key_sp_refcnt(sp)); 545 ipsec_fillpcbcache(pcbsp, m, sp, dir); 546 return sp; 547 } 548 549 /* 550 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 551 * and return a pointer to SP. 552 * OUT: positive: a pointer to the entry for security policy leaf matched. 553 * NULL: no apropreate SP found, the following value is set to error. 554 * 0 : bypass 555 * EACCES : discard packet. 556 * ENOENT : ipsec_acquire() in progress, maybe. 557 * others : error occurred. 558 */ 559 struct secpolicy * 560 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 561 { 562 struct secpolicyindex spidx; 563 struct secpolicy *sp; 564 565 KASSERT(m != NULL); 566 KASSERT(error != NULL); 567 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 568 569 sp = NULL; 570 571 /* Make an index to look for a policy. */ 572 *error = ipsec_setspidx(m, &spidx, (flag & IP_FORWARDING) ? 0 : 1); 573 if (*error != 0) { 574 IPSECLOG(LOG_DEBUG, "setpidx failed, dir %u flag %u\n", dir, flag); 575 memset(&spidx, 0, sizeof (spidx)); 576 return NULL; 577 } 578 579 spidx.dir = dir; 580 581 if (key_havesp(dir)) { 582 sp = KEY_LOOKUP_SP_BYSPIDX(&spidx, dir); 583 } 584 585 if (sp == NULL) /* no SP found, use system default */ 586 sp = KEY_GET_DEFAULT_SP(spidx.dst.sa.sa_family); 587 KASSERT(sp != NULL); 588 return sp; 589 } 590 591 struct secpolicy * 592 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 593 struct inpcb *inp) 594 { 595 struct secpolicy *sp; 596 597 *error = 0; 598 599 if (inp == NULL) { 600 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 601 } else { 602 KASSERT(inp->inp_socket != NULL); 603 sp = ipsec_getpolicybysock(m, dir, (struct inpcb_hdr *)inp, error); 604 } 605 if (sp == NULL) { 606 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 607 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 608 return NULL; 609 } 610 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 611 switch (sp->policy) { 612 case IPSEC_POLICY_ENTRUST: 613 default: 614 printf("%s: invalid policy %u\n", __func__, sp->policy); 615 /* fall thru... */ 616 case IPSEC_POLICY_DISCARD: 617 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 618 *error = -EINVAL; /* packet is discarded by caller */ 619 break; 620 case IPSEC_POLICY_BYPASS: 621 case IPSEC_POLICY_NONE: 622 KEY_SP_UNREF(&sp); 623 sp = NULL; /* NB: force NULL result */ 624 break; 625 case IPSEC_POLICY_IPSEC: 626 KASSERT(sp->req != NULL); 627 break; 628 } 629 if (*error != 0) { 630 KEY_SP_UNREF(&sp); 631 sp = NULL; 632 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 633 } 634 return sp; 635 } 636 637 int 638 ipsec4_output(struct mbuf *m, struct inpcb *inp, int flags, 639 u_long *mtu, bool *natt_frag, bool *done) 640 { 641 struct secpolicy *sp = NULL; 642 int error, s; 643 644 /* 645 * Check the security policy (SP) for the packet and, if required, 646 * do IPsec-related processing. There are two cases here; the first 647 * time a packet is sent through it will be untagged and handled by 648 * ipsec4_checkpolicy(). If the packet is resubmitted to ip_output 649 * (e.g. after AH, ESP, etc. processing), there will be a tag to 650 * bypass the lookup and related policy checking. 651 */ 652 if (ipsec_outdone(m)) { 653 return 0; 654 } 655 s = splsoftnet(); 656 if (inp && ipsec_pcb_skip_ipsec(inp->inp_sp, IPSEC_DIR_OUTBOUND)) { 657 splx(s); 658 return 0; 659 } 660 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, inp); 661 662 /* 663 * There are four return cases: 664 * sp != NULL apply IPsec policy 665 * sp == NULL, error == 0 no IPsec handling needed 666 * sp == NULL, error == -EINVAL discard packet w/o error 667 * sp == NULL, error != 0 discard packet, report error 668 */ 669 if (sp == NULL) { 670 splx(s); 671 if (error) { 672 /* 673 * Hack: -EINVAL is used to signal that a packet 674 * should be silently discarded. This is typically 675 * because we asked key management for an SA and 676 * it was delayed (e.g. kicked up to IKE). 677 */ 678 if (error == -EINVAL) 679 error = 0; 680 m_freem(m); 681 *done = true; 682 return error; 683 } 684 /* No IPsec processing for this packet. */ 685 return 0; 686 } 687 688 /* 689 * Do delayed checksums now because we send before 690 * this is done in the normal processing path. 691 */ 692 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 693 in_delayed_cksum(m); 694 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 695 } 696 697 { 698 u_long _mtu = 0; 699 700 /* Note: callee frees mbuf */ 701 error = ipsec4_process_packet(m, sp->req, &_mtu); 702 703 if (error == 0 && _mtu != 0) { 704 /* 705 * NAT-T ESP fragmentation: do not do IPSec processing 706 * now, we will do it on each fragmented packet. 707 */ 708 *mtu = _mtu; 709 *natt_frag = true; 710 KEY_SP_UNREF(&sp); 711 splx(s); 712 return 0; 713 } 714 } 715 /* 716 * Preserve KAME behaviour: ENOENT can be returned 717 * when an SA acquire is in progress. Don't propagate 718 * this to user-level; it confuses applications. 719 * 720 * XXX this will go away when the SADB is redone. 721 */ 722 if (error == ENOENT) 723 error = 0; 724 KEY_SP_UNREF(&sp); 725 splx(s); 726 *done = true; 727 return error; 728 } 729 730 int 731 ipsec4_input(struct mbuf *m, int flags) 732 { 733 struct secpolicy *sp; 734 int error, s; 735 736 s = splsoftnet(); 737 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 738 if (sp == NULL) { 739 splx(s); 740 return EINVAL; 741 } 742 743 /* 744 * Check security policy against packet attributes. 745 */ 746 error = ipsec_in_reject(sp, m); 747 KEY_SP_UNREF(&sp); 748 splx(s); 749 if (error) { 750 return error; 751 } 752 753 if (flags == 0) { 754 /* We are done. */ 755 return 0; 756 } 757 758 /* 759 * Peek at the outbound SP for this packet to determine if 760 * it is a Fast Forward candidate. 761 */ 762 s = splsoftnet(); 763 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, NULL); 764 if (sp != NULL) { 765 m->m_flags &= ~M_CANFASTFWD; 766 KEY_SP_UNREF(&sp); 767 } 768 splx(s); 769 return 0; 770 } 771 772 int 773 ipsec4_forward(struct mbuf *m, int *destmtu) 774 { 775 /* 776 * If the packet is routed over IPsec tunnel, tell the 777 * originator the tunnel MTU. 778 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 779 * XXX quickhack!!! 780 */ 781 struct secpolicy *sp; 782 size_t ipsechdr; 783 int error; 784 785 sp = ipsec4_getpolicybyaddr(m, 786 IPSEC_DIR_OUTBOUND, IP_FORWARDING, &error); 787 if (sp == NULL) { 788 return EINVAL; 789 } 790 791 /* Count IPsec header size. */ 792 ipsechdr = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, NULL); 793 794 /* 795 * Find the correct route for outer IPv4 header, compute tunnel MTU. 796 */ 797 if (sp->req) { 798 struct route *ro; 799 struct rtentry *rt; 800 struct secasvar *sav = NULL; 801 802 error = key_checkrequest(sp->req, &sav); 803 if (error != 0) 804 return error; 805 ro = &sav->sah->sa_route; 806 rt = rtcache_validate(ro); 807 if (rt && rt->rt_ifp) { 808 *destmtu = rt->rt_rmx.rmx_mtu ? 809 rt->rt_rmx.rmx_mtu : rt->rt_ifp->if_mtu; 810 *destmtu -= ipsechdr; 811 } 812 rtcache_unref(rt, ro); 813 KEY_SA_UNREF(&sav); 814 } 815 KEY_SP_UNREF(&sp); 816 return 0; 817 } 818 819 #ifdef INET6 820 struct secpolicy * 821 ipsec6_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 822 struct in6pcb *in6p) 823 { 824 struct secpolicy *sp; 825 826 *error = 0; 827 828 if (in6p == NULL) { 829 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 830 } else { 831 KASSERT(in6p->in6p_socket != NULL); 832 sp = ipsec_getpolicybysock(m, dir, (struct inpcb_hdr *)in6p, error); 833 } 834 if (sp == NULL) { 835 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 836 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 837 return NULL; 838 } 839 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 840 switch (sp->policy) { 841 case IPSEC_POLICY_ENTRUST: 842 default: 843 printf("%s: invalid policy %u\n", __func__, sp->policy); 844 /* fall thru... */ 845 case IPSEC_POLICY_DISCARD: 846 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 847 *error = -EINVAL; /* packet is discarded by caller */ 848 break; 849 case IPSEC_POLICY_BYPASS: 850 case IPSEC_POLICY_NONE: 851 KEY_SP_UNREF(&sp); 852 sp = NULL; /* NB: force NULL result */ 853 break; 854 case IPSEC_POLICY_IPSEC: 855 KASSERT(sp->req != NULL); 856 break; 857 } 858 if (*error != 0) { 859 KEY_SP_UNREF(&sp); 860 sp = NULL; 861 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 862 } 863 return sp; 864 } 865 #endif /* INET6 */ 866 867 static int 868 ipsec4_setspidx_inpcb(struct mbuf *m, struct inpcb *pcb) 869 { 870 int error; 871 872 KASSERT(pcb != NULL); 873 KASSERT(pcb->inp_sp != NULL); 874 KASSERT(pcb->inp_sp->sp_out != NULL); 875 KASSERT(pcb->inp_sp->sp_in != NULL); 876 877 error = ipsec_setspidx(m, &pcb->inp_sp->sp_in->spidx, 1); 878 if (error == 0) { 879 pcb->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 880 pcb->inp_sp->sp_out->spidx = pcb->inp_sp->sp_in->spidx; 881 pcb->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 882 } else { 883 memset(&pcb->inp_sp->sp_in->spidx, 0, 884 sizeof(pcb->inp_sp->sp_in->spidx)); 885 memset(&pcb->inp_sp->sp_out->spidx, 0, 886 sizeof(pcb->inp_sp->sp_in->spidx)); 887 } 888 return error; 889 } 890 891 #ifdef INET6 892 static int 893 ipsec6_setspidx_in6pcb(struct mbuf *m, struct in6pcb *pcb) 894 { 895 struct secpolicyindex *spidx; 896 int error; 897 898 KASSERT(pcb != NULL); 899 KASSERT(pcb->in6p_sp != NULL); 900 KASSERT(pcb->in6p_sp->sp_out != NULL); 901 KASSERT(pcb->in6p_sp->sp_in != NULL); 902 903 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 904 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 905 906 spidx = &pcb->in6p_sp->sp_in->spidx; 907 error = ipsec_setspidx(m, spidx, 1); 908 if (error) 909 goto bad; 910 spidx->dir = IPSEC_DIR_INBOUND; 911 912 spidx = &pcb->in6p_sp->sp_out->spidx; 913 error = ipsec_setspidx(m, spidx, 1); 914 if (error) 915 goto bad; 916 spidx->dir = IPSEC_DIR_OUTBOUND; 917 918 return 0; 919 920 bad: 921 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 922 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 923 return error; 924 } 925 #endif 926 927 /* 928 * configure security policy index (src/dst/proto/sport/dport) 929 * by looking at the content of mbuf. 930 * the caller is responsible for error recovery (like clearing up spidx). 931 */ 932 static int 933 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 934 { 935 struct ip *ip = NULL; 936 struct ip ipbuf; 937 u_int v; 938 struct mbuf *n; 939 int len; 940 int error; 941 942 KASSERT(m != NULL); 943 944 /* 945 * validate m->m_pkthdr.len. we see incorrect length if we 946 * mistakenly call this function with inconsistent mbuf chain 947 * (like 4.4BSD tcp/udp processing). XXX should we panic here? 948 */ 949 len = 0; 950 for (n = m; n; n = n->m_next) 951 len += n->m_len; 952 if (m->m_pkthdr.len != len) { 953 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 954 "total of m_len(%d) != pkthdr.len(%d), ignored.\n", 955 len, m->m_pkthdr.len); 956 return EINVAL; 957 } 958 959 if (m->m_pkthdr.len < sizeof(struct ip)) { 960 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 961 "pkthdr.len(%d) < sizeof(struct ip), ignored.\n", 962 m->m_pkthdr.len); 963 return EINVAL; 964 } 965 966 if (m->m_len >= sizeof(*ip)) 967 ip = mtod(m, struct ip *); 968 else { 969 m_copydata(m, 0, sizeof(ipbuf), &ipbuf); 970 ip = &ipbuf; 971 } 972 v = ip->ip_v; 973 switch (v) { 974 case 4: 975 error = ipsec4_setspidx_ipaddr(m, spidx); 976 if (error) 977 return error; 978 ipsec4_get_ulp(m, spidx, needport); 979 return 0; 980 #ifdef INET6 981 case 6: 982 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 983 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 984 "pkthdr.len(%d) < sizeof(struct ip6_hdr), " 985 "ignored.\n", m->m_pkthdr.len); 986 return EINVAL; 987 } 988 error = ipsec6_setspidx_ipaddr(m, spidx); 989 if (error) 990 return error; 991 ipsec6_get_ulp(m, spidx, needport); 992 return 0; 993 #endif 994 default: 995 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 996 "unknown IP version %u, ignored.\n", v); 997 return EINVAL; 998 } 999 } 1000 1001 static void 1002 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 1003 { 1004 u_int8_t nxt; 1005 int off; 1006 1007 /* sanity check */ 1008 KASSERT(m != NULL); 1009 KASSERTMSG(m->m_pkthdr.len >= sizeof(struct ip), "packet too short"); 1010 1011 /* NB: ip_input() flips it into host endian XXX need more checking */ 1012 if (m->m_len >= sizeof(struct ip)) { 1013 struct ip *ip = mtod(m, struct ip *); 1014 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 1015 goto done; 1016 off = ip->ip_hl << 2; 1017 nxt = ip->ip_p; 1018 } else { 1019 struct ip ih; 1020 1021 m_copydata(m, 0, sizeof (struct ip), &ih); 1022 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 1023 goto done; 1024 off = ih.ip_hl << 2; 1025 nxt = ih.ip_p; 1026 } 1027 1028 while (off < m->m_pkthdr.len) { 1029 struct ip6_ext ip6e; 1030 struct tcphdr th; 1031 struct udphdr uh; 1032 struct icmp icmph; 1033 1034 switch (nxt) { 1035 case IPPROTO_TCP: 1036 spidx->ul_proto = nxt; 1037 if (!needport) 1038 goto done_proto; 1039 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1040 goto done; 1041 m_copydata(m, off, sizeof (th), &th); 1042 spidx->src.sin.sin_port = th.th_sport; 1043 spidx->dst.sin.sin_port = th.th_dport; 1044 return; 1045 case IPPROTO_UDP: 1046 spidx->ul_proto = nxt; 1047 if (!needport) 1048 goto done_proto; 1049 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1050 goto done; 1051 m_copydata(m, off, sizeof (uh), &uh); 1052 spidx->src.sin.sin_port = uh.uh_sport; 1053 spidx->dst.sin.sin_port = uh.uh_dport; 1054 return; 1055 case IPPROTO_AH: 1056 if (m->m_pkthdr.len > off + sizeof(ip6e)) 1057 goto done; 1058 /* XXX sigh, this works but is totally bogus */ 1059 m_copydata(m, off, sizeof(ip6e), &ip6e); 1060 off += (ip6e.ip6e_len + 2) << 2; 1061 nxt = ip6e.ip6e_nxt; 1062 break; 1063 case IPPROTO_ICMP: 1064 spidx->ul_proto = nxt; 1065 if (off + sizeof(struct icmp) > m->m_pkthdr.len) 1066 return; 1067 m_copydata(m, off, sizeof(icmph), &icmph); 1068 ((struct sockaddr_in *)&spidx->src)->sin_port = 1069 htons((uint16_t)icmph.icmp_type); 1070 ((struct sockaddr_in *)&spidx->dst)->sin_port = 1071 htons((uint16_t)icmph.icmp_code); 1072 return; 1073 default: 1074 /* XXX intermediate headers??? */ 1075 spidx->ul_proto = nxt; 1076 goto done_proto; 1077 } 1078 } 1079 done: 1080 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1081 done_proto: 1082 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 1083 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 1084 } 1085 1086 /* assumes that m is sane */ 1087 static int 1088 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1089 { 1090 static const struct sockaddr_in template = { 1091 sizeof (struct sockaddr_in), 1092 AF_INET, 1093 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 1094 }; 1095 1096 spidx->src.sin = template; 1097 spidx->dst.sin = template; 1098 1099 if (m->m_len < sizeof (struct ip)) { 1100 m_copydata(m, offsetof(struct ip, ip_src), 1101 sizeof(struct in_addr), &spidx->src.sin.sin_addr); 1102 m_copydata(m, offsetof(struct ip, ip_dst), 1103 sizeof(struct in_addr), &spidx->dst.sin.sin_addr); 1104 } else { 1105 struct ip *ip = mtod(m, struct ip *); 1106 spidx->src.sin.sin_addr = ip->ip_src; 1107 spidx->dst.sin.sin_addr = ip->ip_dst; 1108 } 1109 1110 spidx->prefs = sizeof(struct in_addr) << 3; 1111 spidx->prefd = sizeof(struct in_addr) << 3; 1112 1113 return 0; 1114 } 1115 1116 #ifdef INET6 1117 static void 1118 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, 1119 int needport) 1120 { 1121 int off, nxt; 1122 struct tcphdr th; 1123 struct udphdr uh; 1124 struct icmp6_hdr icmph; 1125 1126 KASSERT(m != NULL); 1127 1128 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1129 printf("%s:\n", __func__); 1130 kdebug_mbuf(m); 1131 } 1132 1133 /* set default */ 1134 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1135 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 1136 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 1137 1138 nxt = -1; 1139 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 1140 if (off < 0 || m->m_pkthdr.len < off) 1141 return; 1142 1143 switch (nxt) { 1144 case IPPROTO_TCP: 1145 spidx->ul_proto = nxt; 1146 if (!needport) 1147 break; 1148 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1149 break; 1150 m_copydata(m, off, sizeof(th), &th); 1151 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 1152 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 1153 break; 1154 case IPPROTO_UDP: 1155 spidx->ul_proto = nxt; 1156 if (!needport) 1157 break; 1158 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1159 break; 1160 m_copydata(m, off, sizeof(uh), &uh); 1161 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 1162 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 1163 break; 1164 case IPPROTO_ICMPV6: 1165 spidx->ul_proto = nxt; 1166 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 1167 break; 1168 m_copydata(m, off, sizeof(icmph), &icmph); 1169 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 1170 htons((uint16_t)icmph.icmp6_type); 1171 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 1172 htons((uint16_t)icmph.icmp6_code); 1173 break; 1174 default: 1175 /* XXX intermediate headers??? */ 1176 spidx->ul_proto = nxt; 1177 break; 1178 } 1179 } 1180 1181 /* assumes that m is sane */ 1182 static int 1183 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1184 { 1185 struct ip6_hdr *ip6 = NULL; 1186 struct ip6_hdr ip6buf; 1187 struct sockaddr_in6 *sin6; 1188 1189 if (m->m_len >= sizeof(*ip6)) 1190 ip6 = mtod(m, struct ip6_hdr *); 1191 else { 1192 m_copydata(m, 0, sizeof(ip6buf), &ip6buf); 1193 ip6 = &ip6buf; 1194 } 1195 1196 sin6 = (struct sockaddr_in6 *)&spidx->src; 1197 memset(sin6, 0, sizeof(*sin6)); 1198 sin6->sin6_family = AF_INET6; 1199 sin6->sin6_len = sizeof(struct sockaddr_in6); 1200 memcpy(&sin6->sin6_addr, &ip6->ip6_src, sizeof(ip6->ip6_src)); 1201 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 1202 sin6->sin6_addr.s6_addr16[1] = 0; 1203 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 1204 } 1205 spidx->prefs = sizeof(struct in6_addr) << 3; 1206 1207 sin6 = (struct sockaddr_in6 *)&spidx->dst; 1208 memset(sin6, 0, sizeof(*sin6)); 1209 sin6->sin6_family = AF_INET6; 1210 sin6->sin6_len = sizeof(struct sockaddr_in6); 1211 memcpy(&sin6->sin6_addr, &ip6->ip6_dst, sizeof(ip6->ip6_dst)); 1212 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 1213 sin6->sin6_addr.s6_addr16[1] = 0; 1214 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 1215 } 1216 spidx->prefd = sizeof(struct in6_addr) << 3; 1217 1218 return 0; 1219 } 1220 #endif 1221 1222 static void 1223 ipsec_delpcbpolicy(struct inpcbpolicy *p) 1224 { 1225 1226 kmem_intr_free(p, sizeof(*p)); 1227 } 1228 1229 /* initialize policy in PCB */ 1230 int 1231 ipsec_init_policy(struct socket *so, struct inpcbpolicy **policy) 1232 { 1233 struct inpcbpolicy *new; 1234 1235 KASSERT(so != NULL); 1236 KASSERT(policy != NULL); 1237 1238 new = kmem_intr_zalloc(sizeof(*new), KM_NOSLEEP); 1239 if (new == NULL) { 1240 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1241 return ENOBUFS; 1242 } 1243 1244 if (IPSEC_PRIVILEGED_SO(so)) 1245 new->priv = 1; 1246 else 1247 new->priv = 0; 1248 1249 /* 1250 * These SPs are dummy. Never be used because the policy 1251 * is ENTRUST. See ipsec_getpolicybysock. 1252 */ 1253 new->sp_in = kmem_intr_zalloc(sizeof(struct secpolicy), KM_NOSLEEP); 1254 if (new->sp_in == NULL) { 1255 ipsec_delpcbpolicy(new); 1256 return ENOBUFS; 1257 } 1258 new->sp_in->state = IPSEC_SPSTATE_ALIVE; 1259 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 1260 new->sp_in->created = 0; /* Indicates dummy */ 1261 1262 new->sp_out = kmem_intr_zalloc(sizeof(struct secpolicy), KM_NOSLEEP); 1263 if (new->sp_out == NULL) { 1264 kmem_intr_free(new->sp_in, sizeof(struct secpolicy)); 1265 ipsec_delpcbpolicy(new); 1266 return ENOBUFS; 1267 } 1268 new->sp_out->state = IPSEC_SPSTATE_ALIVE; 1269 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 1270 new->sp_out->created = 0; /* Indicates dummy */ 1271 1272 *policy = new; 1273 1274 return 0; 1275 } 1276 1277 #if 0 /* unused */ 1278 /* copy old ipsec policy into new */ 1279 int 1280 ipsec_copy_policy(const struct inpcbpolicy *old, struct inpcbpolicy *new) 1281 { 1282 struct secpolicy *sp; 1283 1284 sp = ipsec_deepcopy_policy(old->sp_in); 1285 if (sp) { 1286 KEY_SP_UNREF(&new->sp_in); 1287 new->sp_in = sp; 1288 } else 1289 return ENOBUFS; 1290 1291 sp = ipsec_deepcopy_policy(old->sp_out); 1292 if (sp) { 1293 KEY_SP_UNREF(&new->sp_out); 1294 new->sp_out = sp; 1295 } else 1296 return ENOBUFS; 1297 1298 new->priv = old->priv; 1299 1300 return 0; 1301 } 1302 1303 /* deep-copy a policy in PCB */ 1304 static struct secpolicy * 1305 ipsec_deepcopy_policy(const struct secpolicy *src) 1306 { 1307 struct ipsecrequest *newchain = NULL; 1308 const struct ipsecrequest *p; 1309 struct ipsecrequest **q; 1310 struct secpolicy *dst; 1311 1312 if (src == NULL) 1313 return NULL; 1314 dst = KEY_NEWSP(); 1315 if (dst == NULL) 1316 return NULL; 1317 1318 /* 1319 * deep-copy IPsec request chain. This is required since struct 1320 * ipsecrequest is not reference counted. 1321 */ 1322 q = &newchain; 1323 for (p = src->req; p; p = p->next) { 1324 *q = kmem_zalloc(sizeof(**q), KM_SLEEP); 1325 (*q)->next = NULL; 1326 1327 (*q)->saidx.proto = p->saidx.proto; 1328 (*q)->saidx.mode = p->saidx.mode; 1329 (*q)->level = p->level; 1330 (*q)->saidx.reqid = p->saidx.reqid; 1331 1332 memcpy(&(*q)->saidx.src, &p->saidx.src, sizeof((*q)->saidx.src)); 1333 memcpy(&(*q)->saidx.dst, &p->saidx.dst, sizeof((*q)->saidx.dst)); 1334 1335 (*q)->sp = dst; 1336 1337 q = &((*q)->next); 1338 } 1339 1340 dst->req = newchain; 1341 dst->state = src->state; 1342 dst->policy = src->policy; 1343 /* do not touch the refcnt fields */ 1344 1345 return dst; 1346 } 1347 #endif 1348 1349 static void 1350 ipsec_destroy_policy(struct secpolicy *sp) 1351 { 1352 1353 if (sp->created == 0) 1354 /* It's dummy. We can simply free it */ 1355 kmem_intr_free(sp, sizeof(*sp)); 1356 else { 1357 /* 1358 * We cannot destroy here because it can be called in 1359 * softint. So mark the SP as DEAD and let the timer 1360 * destroy it. See key_timehandler_spd. 1361 */ 1362 sp->state = IPSEC_SPSTATE_DEAD; 1363 } 1364 } 1365 1366 /* set policy and ipsec request if present. */ 1367 static int 1368 ipsec_set_policy( 1369 struct secpolicy **policy, 1370 int optname, 1371 const void *request, 1372 size_t len, 1373 kauth_cred_t cred 1374 ) 1375 { 1376 const struct sadb_x_policy *xpl; 1377 struct secpolicy *newsp = NULL, *oldsp; 1378 int error; 1379 1380 KASSERT(!cpu_softintr_p()); 1381 1382 /* sanity check. */ 1383 if (policy == NULL || *policy == NULL || request == NULL) 1384 return EINVAL; 1385 if (len < sizeof(*xpl)) 1386 return EINVAL; 1387 xpl = (const struct sadb_x_policy *)request; 1388 1389 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1390 printf("%s: passed policy\n", __func__); 1391 kdebug_sadb_x_policy((const struct sadb_ext *)xpl); 1392 } 1393 1394 /* check policy type */ 1395 /* ipsec_set_policy() accepts IPSEC, ENTRUST and BYPASS. */ 1396 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 1397 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1398 return EINVAL; 1399 1400 /* check privileged socket */ 1401 if (xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1402 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPSEC, 1403 KAUTH_REQ_NETWORK_IPSEC_BYPASS, NULL, NULL, NULL); 1404 if (error) 1405 return (error); 1406 } 1407 1408 /* allocation new SP entry */ 1409 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1410 return error; 1411 1412 key_init_sp(newsp); 1413 newsp->created = time_uptime; 1414 /* Insert the global list for SPs for sockets */ 1415 key_socksplist_add(newsp); 1416 1417 /* clear old SP and set new SP */ 1418 oldsp = *policy; 1419 *policy = newsp; 1420 ipsec_destroy_policy(oldsp); 1421 1422 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1423 printf("%s: new policy\n", __func__); 1424 kdebug_secpolicy(newsp); 1425 } 1426 1427 return 0; 1428 } 1429 1430 static int 1431 ipsec_get_policy(struct secpolicy *policy, struct mbuf **mp) 1432 { 1433 1434 /* sanity check. */ 1435 if (policy == NULL || mp == NULL) 1436 return EINVAL; 1437 1438 *mp = key_sp2msg(policy); 1439 if (!*mp) { 1440 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1441 return ENOBUFS; 1442 } 1443 1444 (*mp)->m_type = MT_DATA; 1445 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1446 printf("%s:\n", __func__); 1447 kdebug_mbuf(*mp); 1448 } 1449 1450 return 0; 1451 } 1452 1453 int 1454 ipsec4_set_policy(struct inpcb *inp, int optname, const void *request, 1455 size_t len, kauth_cred_t cred) 1456 { 1457 const struct sadb_x_policy *xpl; 1458 struct secpolicy **policy; 1459 1460 KASSERT(!cpu_softintr_p()); 1461 KASSERT(inp_locked(inp)); 1462 1463 /* sanity check. */ 1464 if (inp == NULL || request == NULL) 1465 return EINVAL; 1466 if (len < sizeof(*xpl)) 1467 return EINVAL; 1468 xpl = (const struct sadb_x_policy *)request; 1469 1470 KASSERT(inp->inp_sp != NULL); 1471 1472 /* select direction */ 1473 switch (xpl->sadb_x_policy_dir) { 1474 case IPSEC_DIR_INBOUND: 1475 policy = &inp->inp_sp->sp_in; 1476 break; 1477 case IPSEC_DIR_OUTBOUND: 1478 policy = &inp->inp_sp->sp_out; 1479 break; 1480 default: 1481 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1482 xpl->sadb_x_policy_dir); 1483 return EINVAL; 1484 } 1485 1486 return ipsec_set_policy(policy, optname, request, len, cred); 1487 } 1488 1489 int 1490 ipsec4_get_policy(struct inpcb *inp, const void *request, size_t len, 1491 struct mbuf **mp) 1492 { 1493 const struct sadb_x_policy *xpl; 1494 struct secpolicy *policy; 1495 1496 /* sanity check. */ 1497 if (inp == NULL || request == NULL || mp == NULL) 1498 return EINVAL; 1499 KASSERT(inp->inp_sp != NULL); 1500 if (len < sizeof(*xpl)) 1501 return EINVAL; 1502 xpl = (const struct sadb_x_policy *)request; 1503 1504 /* select direction */ 1505 switch (xpl->sadb_x_policy_dir) { 1506 case IPSEC_DIR_INBOUND: 1507 policy = inp->inp_sp->sp_in; 1508 break; 1509 case IPSEC_DIR_OUTBOUND: 1510 policy = inp->inp_sp->sp_out; 1511 break; 1512 default: 1513 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1514 xpl->sadb_x_policy_dir); 1515 return EINVAL; 1516 } 1517 1518 return ipsec_get_policy(policy, mp); 1519 } 1520 1521 /* delete policy in PCB */ 1522 int 1523 ipsec4_delete_pcbpolicy(struct inpcb *inp) 1524 { 1525 1526 KASSERT(inp != NULL); 1527 1528 if (inp->inp_sp == NULL) 1529 return 0; 1530 1531 if (inp->inp_sp->sp_in != NULL) 1532 ipsec_destroy_policy(inp->inp_sp->sp_in); 1533 1534 if (inp->inp_sp->sp_out != NULL) 1535 ipsec_destroy_policy(inp->inp_sp->sp_out); 1536 1537 ipsec_invalpcbcache(inp->inp_sp, IPSEC_DIR_ANY); 1538 1539 ipsec_delpcbpolicy(inp->inp_sp); 1540 inp->inp_sp = NULL; 1541 1542 return 0; 1543 } 1544 1545 #ifdef INET6 1546 int 1547 ipsec6_set_policy(struct in6pcb *in6p, int optname, const void *request, 1548 size_t len, kauth_cred_t cred) 1549 { 1550 const struct sadb_x_policy *xpl; 1551 struct secpolicy **policy; 1552 1553 KASSERT(!cpu_softintr_p()); 1554 KASSERT(in6p_locked(in6p)); 1555 1556 /* sanity check. */ 1557 if (in6p == NULL || request == NULL) 1558 return EINVAL; 1559 if (len < sizeof(*xpl)) 1560 return EINVAL; 1561 xpl = (const struct sadb_x_policy *)request; 1562 1563 /* select direction */ 1564 switch (xpl->sadb_x_policy_dir) { 1565 case IPSEC_DIR_INBOUND: 1566 policy = &in6p->in6p_sp->sp_in; 1567 break; 1568 case IPSEC_DIR_OUTBOUND: 1569 policy = &in6p->in6p_sp->sp_out; 1570 break; 1571 default: 1572 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1573 xpl->sadb_x_policy_dir); 1574 return EINVAL; 1575 } 1576 1577 return ipsec_set_policy(policy, optname, request, len, cred); 1578 } 1579 1580 int 1581 ipsec6_get_policy(struct in6pcb *in6p, const void *request, size_t len, 1582 struct mbuf **mp) 1583 { 1584 const struct sadb_x_policy *xpl; 1585 struct secpolicy *policy; 1586 1587 /* sanity check. */ 1588 if (in6p == NULL || request == NULL || mp == NULL) 1589 return EINVAL; 1590 KASSERT(in6p->in6p_sp != NULL); 1591 if (len < sizeof(*xpl)) 1592 return EINVAL; 1593 xpl = (const struct sadb_x_policy *)request; 1594 1595 /* select direction */ 1596 switch (xpl->sadb_x_policy_dir) { 1597 case IPSEC_DIR_INBOUND: 1598 policy = in6p->in6p_sp->sp_in; 1599 break; 1600 case IPSEC_DIR_OUTBOUND: 1601 policy = in6p->in6p_sp->sp_out; 1602 break; 1603 default: 1604 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1605 xpl->sadb_x_policy_dir); 1606 return EINVAL; 1607 } 1608 1609 return ipsec_get_policy(policy, mp); 1610 } 1611 1612 int 1613 ipsec6_delete_pcbpolicy(struct in6pcb *in6p) 1614 { 1615 1616 KASSERT(in6p != NULL); 1617 1618 if (in6p->in6p_sp == NULL) 1619 return 0; 1620 1621 if (in6p->in6p_sp->sp_in != NULL) 1622 ipsec_destroy_policy(in6p->in6p_sp->sp_in); 1623 1624 if (in6p->in6p_sp->sp_out != NULL) 1625 ipsec_destroy_policy(in6p->in6p_sp->sp_out); 1626 1627 ipsec_invalpcbcache(in6p->in6p_sp, IPSEC_DIR_ANY); 1628 1629 ipsec_delpcbpolicy(in6p->in6p_sp); 1630 in6p->in6p_sp = NULL; 1631 1632 return 0; 1633 } 1634 #endif 1635 1636 /* 1637 * return current level. 1638 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1639 */ 1640 u_int 1641 ipsec_get_reqlevel(const struct ipsecrequest *isr) 1642 { 1643 u_int level = 0; 1644 u_int esp_trans_deflev, esp_net_deflev; 1645 u_int ah_trans_deflev, ah_net_deflev; 1646 1647 KASSERT(isr != NULL); 1648 KASSERT(isr->sp != NULL); 1649 KASSERTMSG( 1650 isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1651 "af family mismatch, src %u, dst %u", 1652 isr->sp->spidx.src.sa.sa_family, isr->sp->spidx.dst.sa.sa_family); 1653 1654 /* XXX note that we have ipseclog() expanded here - code sync issue */ 1655 #define IPSEC_CHECK_DEFAULT(lev) \ 1656 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1657 && (lev) != IPSEC_LEVEL_UNIQUE) ? \ 1658 (ipsec_debug ? log(LOG_INFO, "fixed system default level " #lev \ 1659 ":%d->%d\n", (lev), IPSEC_LEVEL_REQUIRE) : (void)0), \ 1660 (lev) = IPSEC_LEVEL_REQUIRE, (lev) \ 1661 : (lev)) 1662 1663 /* set default level */ 1664 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1665 #ifdef INET 1666 case AF_INET: 1667 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_trans_deflev); 1668 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_net_deflev); 1669 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_trans_deflev); 1670 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_net_deflev); 1671 break; 1672 #endif 1673 #ifdef INET6 1674 case AF_INET6: 1675 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_trans_deflev); 1676 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_net_deflev); 1677 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_trans_deflev); 1678 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_net_deflev); 1679 break; 1680 #endif /* INET6 */ 1681 default: 1682 panic("%s: unknown af %u", __func__, 1683 isr->sp->spidx.src.sa.sa_family); 1684 } 1685 1686 #undef IPSEC_CHECK_DEFAULT 1687 1688 /* set level */ 1689 switch (isr->level) { 1690 case IPSEC_LEVEL_DEFAULT: 1691 switch (isr->saidx.proto) { 1692 case IPPROTO_ESP: 1693 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1694 level = esp_net_deflev; 1695 else 1696 level = esp_trans_deflev; 1697 break; 1698 case IPPROTO_AH: 1699 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1700 level = ah_net_deflev; 1701 else 1702 level = ah_trans_deflev; 1703 break; 1704 case IPPROTO_IPCOMP: 1705 /* 1706 * we don't really care, as IPcomp document says that 1707 * we shouldn't compress small packets 1708 */ 1709 level = IPSEC_LEVEL_USE; 1710 break; 1711 default: 1712 panic("%s: Illegal protocol defined %u", __func__, 1713 isr->saidx.proto); 1714 } 1715 break; 1716 1717 case IPSEC_LEVEL_USE: 1718 case IPSEC_LEVEL_REQUIRE: 1719 level = isr->level; 1720 break; 1721 case IPSEC_LEVEL_UNIQUE: 1722 level = IPSEC_LEVEL_REQUIRE; 1723 break; 1724 1725 default: 1726 panic("%s: Illegal IPsec level %u", __func__, isr->level); 1727 } 1728 1729 return level; 1730 } 1731 1732 /* 1733 * Check security policy requirements against the actual 1734 * packet contents. Return one if the packet should be 1735 * reject as "invalid"; otherwiser return zero to have the 1736 * packet treated as "valid". 1737 * 1738 * OUT: 1739 * 0: valid 1740 * 1: invalid 1741 */ 1742 int 1743 ipsec_in_reject(const struct secpolicy *sp, const struct mbuf *m) 1744 { 1745 struct ipsecrequest *isr; 1746 1747 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1748 printf("%s: using SP\n", __func__); 1749 kdebug_secpolicy(sp); 1750 } 1751 1752 /* check policy */ 1753 switch (sp->policy) { 1754 case IPSEC_POLICY_DISCARD: 1755 return 1; 1756 case IPSEC_POLICY_BYPASS: 1757 case IPSEC_POLICY_NONE: 1758 return 0; 1759 } 1760 1761 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1762 "invalid policy %u", sp->policy); 1763 1764 /* XXX should compare policy against ipsec header history */ 1765 1766 for (isr = sp->req; isr != NULL; isr = isr->next) { 1767 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1768 continue; 1769 switch (isr->saidx.proto) { 1770 case IPPROTO_ESP: 1771 if ((m->m_flags & M_DECRYPTED) == 0) { 1772 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1773 "ESP m_flags:%x\n", m->m_flags); 1774 return 1; 1775 } 1776 break; 1777 case IPPROTO_AH: 1778 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1779 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1780 "AH m_flags:%x\n", m->m_flags); 1781 return 1; 1782 } 1783 break; 1784 case IPPROTO_IPCOMP: 1785 /* 1786 * we don't really care, as IPcomp document 1787 * says that we shouldn't compress small 1788 * packets, IPComp policy should always be 1789 * treated as being in "use" level. 1790 */ 1791 break; 1792 } 1793 } 1794 return 0; /* valid */ 1795 } 1796 1797 /* 1798 * Check AH/ESP integrity. 1799 * This function is called from tcp_input(), udp_input(), 1800 * and {ah,esp}4_input for tunnel mode 1801 */ 1802 int 1803 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1804 { 1805 struct secpolicy *sp; 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 (inp == 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 *)inp, &error); 1820 1821 if (sp != NULL) { 1822 result = ipsec_in_reject(sp, m); 1823 if (result) 1824 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1825 KEY_SP_UNREF(&sp); 1826 } else { 1827 result = 0; /* XXX should be panic ? 1828 * -> No, there may be error. */ 1829 } 1830 return result; 1831 } 1832 1833 1834 #ifdef INET6 1835 /* 1836 * Check AH/ESP integrity. 1837 * This function is called from tcp6_input(), udp6_input(), 1838 * and {ah,esp}6_input for tunnel mode 1839 */ 1840 int 1841 ipsec6_in_reject(struct mbuf *m, struct in6pcb *in6p) 1842 { 1843 struct secpolicy *sp = NULL; 1844 int error; 1845 int result; 1846 1847 KASSERT(m != NULL); 1848 1849 /* get SP for this packet. 1850 * When we are called from ip_forward(), we call 1851 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1852 */ 1853 if (in6p == NULL) 1854 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1855 else 1856 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1857 (struct inpcb_hdr *)in6p, 1858 &error); 1859 1860 if (sp != NULL) { 1861 result = ipsec_in_reject(sp, m); 1862 if (result) 1863 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1864 KEY_SP_UNREF(&sp); 1865 } else { 1866 result = 0; 1867 } 1868 return result; 1869 } 1870 #endif 1871 1872 /* 1873 * compute the byte size to be occupied by IPsec header. 1874 * in case it is tunneled, it includes the size of outer IP header. 1875 * NOTE: SP passed is free in this function. 1876 */ 1877 static size_t 1878 ipsec_hdrsiz(const struct secpolicy *sp) 1879 { 1880 struct ipsecrequest *isr; 1881 size_t siz; 1882 1883 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1884 printf("%s: using SP\n", __func__); 1885 kdebug_secpolicy(sp); 1886 } 1887 1888 switch (sp->policy) { 1889 case IPSEC_POLICY_DISCARD: 1890 case IPSEC_POLICY_BYPASS: 1891 case IPSEC_POLICY_NONE: 1892 return 0; 1893 } 1894 1895 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1896 "invalid policy %u", sp->policy); 1897 1898 siz = 0; 1899 for (isr = sp->req; isr != NULL; isr = isr->next) { 1900 size_t clen = 0; 1901 struct secasvar *sav = NULL; 1902 int error; 1903 1904 switch (isr->saidx.proto) { 1905 case IPPROTO_ESP: 1906 error = key_checkrequest(isr, &sav); 1907 if (error == 0) { 1908 clen = esp_hdrsiz(sav); 1909 KEY_SA_UNREF(&sav); 1910 } else 1911 clen = esp_hdrsiz(NULL); 1912 break; 1913 case IPPROTO_AH: 1914 error = key_checkrequest(isr, &sav); 1915 if (error == 0) { 1916 clen = ah_hdrsiz(sav); 1917 KEY_SA_UNREF(&sav); 1918 } else 1919 clen = ah_hdrsiz(NULL); 1920 break; 1921 case IPPROTO_IPCOMP: 1922 clen = sizeof(struct ipcomp); 1923 break; 1924 } 1925 1926 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1927 switch (isr->saidx.dst.sa.sa_family) { 1928 case AF_INET: 1929 clen += sizeof(struct ip); 1930 break; 1931 #ifdef INET6 1932 case AF_INET6: 1933 clen += sizeof(struct ip6_hdr); 1934 break; 1935 #endif 1936 default: 1937 IPSECLOG(LOG_ERR, "unknown AF %d in " 1938 "IPsec tunnel SA\n", 1939 ((const struct sockaddr *)&isr->saidx.dst) 1940 ->sa_family); 1941 break; 1942 } 1943 } 1944 siz += clen; 1945 } 1946 1947 return siz; 1948 } 1949 1950 /* This function is called from ip_forward() and ipsec4_hdrsize_tcp(). */ 1951 size_t 1952 ipsec4_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1953 { 1954 struct secpolicy *sp; 1955 int error; 1956 size_t size; 1957 1958 KASSERT(m != NULL); 1959 KASSERTMSG(inp == NULL || inp->inp_socket != NULL, "socket w/o inpcb"); 1960 1961 /* get SP for this packet. 1962 * When we are called from ip_forward(), we call 1963 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1964 */ 1965 if (inp == NULL) 1966 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1967 else 1968 sp = ipsec_getpolicybysock(m, dir, 1969 (struct inpcb_hdr *)inp, &error); 1970 1971 if (sp != NULL) { 1972 size = ipsec_hdrsiz(sp); 1973 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%lu.\n", 1974 (unsigned long)size); 1975 1976 KEY_SP_UNREF(&sp); 1977 } else { 1978 size = 0; /* XXX should be panic ? */ 1979 } 1980 return size; 1981 } 1982 1983 #ifdef INET6 1984 /* This function is called from ipsec6_hdrsize_tcp(), 1985 * and maybe from ip6_forward.() 1986 */ 1987 size_t 1988 ipsec6_hdrsiz(struct mbuf *m, u_int dir, struct in6pcb *in6p) 1989 { 1990 struct secpolicy *sp; 1991 int error; 1992 size_t size; 1993 1994 KASSERT(m != NULL); 1995 KASSERTMSG(in6p == NULL || in6p->in6p_socket != NULL, 1996 "socket w/o inpcb"); 1997 1998 /* get SP for this packet */ 1999 /* XXX Is it right to call with IP_FORWARDING. */ 2000 if (in6p == NULL) 2001 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 2002 else 2003 sp = ipsec_getpolicybysock(m, dir, 2004 (struct inpcb_hdr *)in6p, 2005 &error); 2006 2007 if (sp == NULL) 2008 return 0; 2009 size = ipsec_hdrsiz(sp); 2010 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%zu.\n", size); 2011 KEY_SP_UNREF(&sp); 2012 2013 return size; 2014 } 2015 #endif /*INET6*/ 2016 2017 /* 2018 * Check the variable replay window. 2019 * ipsec_chkreplay() performs replay check before ICV verification. 2020 * ipsec_updatereplay() updates replay bitmap. This must be called after 2021 * ICV verification (it also performs replay check, which is usually done 2022 * beforehand). 2023 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 2024 * 2025 * based on RFC 2401. 2026 */ 2027 int 2028 ipsec_chkreplay(u_int32_t seq, const struct secasvar *sav) 2029 { 2030 const struct secreplay *replay; 2031 u_int32_t diff; 2032 int fr; 2033 u_int32_t wsizeb; /* constant: bits of window size */ 2034 int frlast; /* constant: last frame */ 2035 2036 IPSEC_SPLASSERT_SOFTNET(__func__); 2037 2038 KASSERT(sav != NULL); 2039 KASSERT(sav->replay != NULL); 2040 2041 replay = sav->replay; 2042 2043 if (replay->wsize == 0) 2044 return 1; /* no need to check replay. */ 2045 2046 /* constant */ 2047 frlast = replay->wsize - 1; 2048 wsizeb = replay->wsize << 3; 2049 2050 /* sequence number of 0 is invalid */ 2051 if (seq == 0) 2052 return 0; 2053 2054 /* first time is always okay */ 2055 if (replay->count == 0) 2056 return 1; 2057 2058 if (seq > replay->lastseq) { 2059 /* larger sequences are okay */ 2060 return 1; 2061 } else { 2062 /* seq is equal or less than lastseq. */ 2063 diff = replay->lastseq - seq; 2064 2065 /* over range to check, i.e. too old or wrapped */ 2066 if (diff >= wsizeb) 2067 return 0; 2068 2069 fr = frlast - diff / 8; 2070 2071 /* this packet already seen ? */ 2072 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2073 return 0; 2074 2075 /* out of order but good */ 2076 return 1; 2077 } 2078 } 2079 2080 /* 2081 * check replay counter whether to update or not. 2082 * OUT: 0: OK 2083 * 1: NG 2084 */ 2085 int 2086 ipsec_updatereplay(u_int32_t seq, const struct secasvar *sav) 2087 { 2088 struct secreplay *replay; 2089 u_int32_t diff; 2090 int fr; 2091 u_int32_t wsizeb; /* constant: bits of window size */ 2092 int frlast; /* constant: last frame */ 2093 char buf[INET6_ADDRSTRLEN]; 2094 2095 IPSEC_SPLASSERT_SOFTNET(__func__); 2096 2097 KASSERT(sav != NULL); 2098 KASSERT(sav->replay != NULL); 2099 2100 replay = sav->replay; 2101 2102 if (replay->wsize == 0) 2103 goto ok; /* no need to check replay. */ 2104 2105 /* constant */ 2106 frlast = replay->wsize - 1; 2107 wsizeb = replay->wsize << 3; 2108 2109 /* sequence number of 0 is invalid */ 2110 if (seq == 0) 2111 return 1; 2112 2113 /* first time */ 2114 if (replay->count == 0) { 2115 replay->lastseq = seq; 2116 memset(replay->bitmap, 0, replay->wsize); 2117 (replay->bitmap)[frlast] = 1; 2118 goto ok; 2119 } 2120 2121 if (seq > replay->lastseq) { 2122 /* seq is larger than lastseq. */ 2123 diff = seq - replay->lastseq; 2124 2125 /* new larger sequence number */ 2126 if (diff < wsizeb) { 2127 /* In window */ 2128 /* set bit for this packet */ 2129 vshiftl(replay->bitmap, diff, replay->wsize); 2130 (replay->bitmap)[frlast] |= 1; 2131 } else { 2132 /* this packet has a "way larger" */ 2133 memset(replay->bitmap, 0, replay->wsize); 2134 (replay->bitmap)[frlast] = 1; 2135 } 2136 replay->lastseq = seq; 2137 2138 /* larger is good */ 2139 } else { 2140 /* seq is equal or less than lastseq. */ 2141 diff = replay->lastseq - seq; 2142 2143 /* over range to check, i.e. too old or wrapped */ 2144 if (diff >= wsizeb) 2145 return 1; 2146 2147 fr = frlast - diff / 8; 2148 2149 /* this packet already seen ? */ 2150 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2151 return 1; 2152 2153 /* mark as seen */ 2154 (replay->bitmap)[fr] |= (1 << (diff % 8)); 2155 2156 /* out of order but good */ 2157 } 2158 2159 ok: 2160 if (replay->count == ~0) { 2161 2162 /* set overflow flag */ 2163 replay->overflow++; 2164 2165 /* don't increment, no more packets accepted */ 2166 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 2167 return 1; 2168 2169 IPSECLOG(LOG_WARNING, "replay counter made %d cycle. %s\n", 2170 replay->overflow, ipsec_logsastr(sav, buf, sizeof(buf))); 2171 } 2172 2173 replay->count++; 2174 2175 return 0; 2176 } 2177 2178 /* 2179 * shift variable length bunffer to left. 2180 * IN: bitmap: pointer to the buffer 2181 * nbit: the number of to shift. 2182 * wsize: buffer size (bytes). 2183 */ 2184 static void 2185 vshiftl(unsigned char *bitmap, int nbit, int wsize) 2186 { 2187 int s, j, i; 2188 unsigned char over; 2189 2190 for (j = 0; j < nbit; j += 8) { 2191 s = (nbit - j < 8) ? (nbit - j): 8; 2192 bitmap[0] <<= s; 2193 for (i = 1; i < wsize; i++) { 2194 over = (bitmap[i] >> (8 - s)); 2195 bitmap[i] <<= s; 2196 bitmap[i-1] |= over; 2197 } 2198 } 2199 2200 return; 2201 } 2202 2203 /* Return a printable string for the address. */ 2204 const char * 2205 ipsec_address(const union sockaddr_union *sa, char *buf, size_t size) 2206 { 2207 switch (sa->sa.sa_family) { 2208 #if INET 2209 case AF_INET: 2210 in_print(buf, size, &sa->sin.sin_addr); 2211 return buf; 2212 #endif /* INET */ 2213 2214 #if INET6 2215 case AF_INET6: 2216 in6_print(buf, size, &sa->sin6.sin6_addr); 2217 return buf; 2218 #endif /* INET6 */ 2219 2220 default: 2221 return "(unknown address family)"; 2222 } 2223 } 2224 2225 const char * 2226 ipsec_logsastr(const struct secasvar *sav, char *buf, size_t size) 2227 { 2228 const struct secasindex *saidx = &sav->sah->saidx; 2229 char sbuf[IPSEC_ADDRSTRLEN], dbuf[IPSEC_ADDRSTRLEN]; 2230 2231 KASSERTMSG(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 2232 "af family mismatch, src %u, dst %u", 2233 saidx->src.sa.sa_family, saidx->dst.sa.sa_family); 2234 2235 snprintf(buf, size, "SA(SPI=%u src=%s dst=%s)", 2236 (u_int32_t)ntohl(sav->spi), 2237 ipsec_address(&saidx->src, sbuf, sizeof(sbuf)), 2238 ipsec_address(&saidx->dst, dbuf, sizeof(dbuf))); 2239 2240 return buf; 2241 } 2242 2243 void 2244 ipsec_dumpmbuf(struct mbuf *m) 2245 { 2246 int totlen; 2247 int i; 2248 u_char *p; 2249 2250 totlen = 0; 2251 printf("---\n"); 2252 while (m) { 2253 p = mtod(m, u_char *); 2254 for (i = 0; i < m->m_len; i++) { 2255 printf("%02x ", p[i]); 2256 totlen++; 2257 if (totlen % 16 == 0) 2258 printf("\n"); 2259 } 2260 m = m->m_next; 2261 } 2262 if (totlen % 16 != 0) 2263 printf("\n"); 2264 printf("---\n"); 2265 } 2266 2267 #ifdef INET6 2268 struct secpolicy * 2269 ipsec6_check_policy(struct mbuf *m, struct in6pcb *in6p, 2270 int flags, int *needipsecp, int *errorp) 2271 { 2272 struct secpolicy *sp = NULL; 2273 int s; 2274 int error = 0; 2275 int needipsec = 0; 2276 2277 if (!ipsec_outdone(m)) { 2278 s = splsoftnet(); 2279 if (in6p != NULL && 2280 ipsec_pcb_skip_ipsec(in6p->in6p_sp, IPSEC_DIR_OUTBOUND)) { 2281 splx(s); 2282 goto skippolicycheck; 2283 } 2284 sp = ipsec6_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error,in6p); 2285 2286 /* 2287 * There are four return cases: 2288 * sp != NULL apply IPsec policy 2289 * sp == NULL, error == 0 no IPsec handling needed 2290 * sp == NULL, error == -EINVAL discard packet w/o error 2291 * sp == NULL, error != 0 discard packet, report error 2292 */ 2293 2294 splx(s); 2295 if (sp == NULL) { 2296 /* 2297 * Caller must check the error return to see if it needs to discard 2298 * the packet. 2299 */ 2300 needipsec = 0; 2301 } else { 2302 needipsec = 1; 2303 } 2304 } 2305 skippolicycheck:; 2306 2307 *errorp = error; 2308 *needipsecp = needipsec; 2309 return sp; 2310 } 2311 2312 int 2313 ipsec6_input(struct mbuf *m) 2314 { 2315 struct secpolicy *sp; 2316 int s, error; 2317 2318 s = splsoftnet(); 2319 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 2320 if (sp != NULL) { 2321 /* 2322 * Check security policy against packet 2323 * attributes. 2324 */ 2325 error = ipsec_in_reject(sp, m); 2326 KEY_SP_UNREF(&sp); 2327 } else { 2328 /* XXX error stat??? */ 2329 error = EINVAL; 2330 IPSECLOG(LOG_DEBUG, "no SP, packet discarded\n");/*XXX*/ 2331 } 2332 splx(s); 2333 2334 return error; 2335 } 2336 #endif /* INET6 */ 2337 2338 2339 2340 /* XXX this stuff doesn't belong here... */ 2341 2342 static struct xformsw *xforms = NULL; 2343 2344 /* 2345 * Register a transform; typically at system startup. 2346 */ 2347 void 2348 xform_register(struct xformsw *xsp) 2349 { 2350 xsp->xf_next = xforms; 2351 xforms = xsp; 2352 } 2353 2354 /* 2355 * Initialize transform support in an sav. 2356 */ 2357 int 2358 xform_init(struct secasvar *sav, int xftype) 2359 { 2360 struct xformsw *xsp; 2361 2362 if (sav->tdb_xform != NULL) /* previously initialized */ 2363 return 0; 2364 for (xsp = xforms; xsp; xsp = xsp->xf_next) 2365 if (xsp->xf_type == xftype) 2366 return (*xsp->xf_init)(sav, xsp); 2367 2368 IPSECLOG(LOG_DEBUG, "no match for xform type %d\n", xftype); 2369 return EINVAL; 2370 } 2371 2372 void 2373 nat_t_ports_get(struct mbuf *m, u_int16_t *dport, u_int16_t *sport) { 2374 struct m_tag *tag; 2375 2376 if ((tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL))) { 2377 *sport = ((u_int16_t *)(tag + 1))[0]; 2378 *dport = ((u_int16_t *)(tag + 1))[1]; 2379 } else 2380 *sport = *dport = 0; 2381 } 2382 2383 /* 2384 * XXXJRT This should be done as a protosw init call. 2385 */ 2386 void 2387 ipsec_attach(void) 2388 { 2389 2390 ipsec_output_init(); 2391 2392 ipsecstat_percpu = percpu_alloc(sizeof(uint64_t) * IPSEC_NSTATS); 2393 2394 sysctl_net_inet_ipsec_setup(NULL); 2395 #ifdef INET6 2396 sysctl_net_inet6_ipsec6_setup(NULL); 2397 #endif 2398 2399 ah_attach(); 2400 esp_attach(); 2401 ipcomp_attach(); 2402 ipe4_attach(); 2403 #ifdef TCP_SIGNATURE 2404 tcpsignature_attach(); 2405 #endif 2406 } 2407
Indexes created Sun Sep 21 20:09:37 GMT 2025