ipsec.c revision 1.127
1 /* $NetBSD: ipsec.c,v 1.127 2018/02/16 08:56:50 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 1.127 2018/02/16 08:56:50 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 __FreeBSD__ 164 /* net.inet.ipsec */ 165 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, 166 crypto_support, CTLFLAG_RW, &crypto_support,0, ""); 167 #endif /* __FreeBSD__ */ 168 169 #ifdef INET6 170 int ip6_esp_trans_deflev = IPSEC_LEVEL_USE; 171 int ip6_esp_net_deflev = IPSEC_LEVEL_USE; 172 int ip6_ah_trans_deflev = IPSEC_LEVEL_USE; 173 int ip6_ah_net_deflev = IPSEC_LEVEL_USE; 174 struct secpolicy ip6_def_policy; 175 int ip6_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 176 #endif /* INET6 */ 177 178 static int ipsec4_setspidx_inpcb (struct mbuf *, struct inpcb *); 179 #ifdef INET6 180 static int ipsec6_setspidx_in6pcb (struct mbuf *, struct in6pcb *); 181 #endif 182 static int ipsec_setspidx (struct mbuf *, struct secpolicyindex *, int); 183 static void ipsec4_get_ulp (struct mbuf *m, struct secpolicyindex *, int); 184 static int ipsec4_setspidx_ipaddr (struct mbuf *, struct secpolicyindex *); 185 #ifdef INET6 186 static void ipsec6_get_ulp (struct mbuf *m, struct secpolicyindex *, int); 187 static int ipsec6_setspidx_ipaddr (struct mbuf *, struct secpolicyindex *); 188 #endif 189 static void ipsec_delpcbpolicy (struct inpcbpolicy *); 190 #if 0 /* unused */ 191 static struct secpolicy *ipsec_deepcopy_policy (const struct secpolicy *); 192 #endif 193 static int ipsec_set_policy (struct secpolicy **, int, const void *, size_t, 194 kauth_cred_t); 195 static int ipsec_get_policy (struct secpolicy *, struct mbuf **); 196 static void ipsec_destroy_policy(struct secpolicy *); 197 static void vshiftl (unsigned char *, int, int); 198 static size_t ipsec_hdrsiz(const struct secpolicy *, const struct mbuf *); 199 200 /* 201 * Try to validate and use cached policy on a PCB. 202 */ 203 static struct secpolicy * 204 ipsec_checkpcbcache(struct mbuf *m, struct inpcbpolicy *pcbsp, int dir) 205 { 206 struct secpolicyindex spidx; 207 struct secpolicy *sp = NULL; 208 int s; 209 210 KASSERT(IPSEC_DIR_IS_VALID(dir)); 211 KASSERT(pcbsp != NULL); 212 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 213 KASSERT(inph_locked(pcbsp->sp_inph)); 214 215 /* 216 * Checking the generation and sp->state and taking a reference to an SP 217 * must be in a critical section of pserialize. See key_unlink_sp. 218 */ 219 s = pserialize_read_enter(); 220 /* SPD table change invalidate all the caches. */ 221 if (ipsec_spdgen != pcbsp->sp_cache[dir].cachegen) { 222 ipsec_invalpcbcache(pcbsp, dir); 223 goto out; 224 } 225 sp = pcbsp->sp_cache[dir].cachesp; 226 if (sp == NULL) 227 goto out; 228 if (sp->state != IPSEC_SPSTATE_ALIVE) { 229 sp = NULL; 230 ipsec_invalpcbcache(pcbsp, dir); 231 goto out; 232 } 233 if ((pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) == 0) { 234 /* NB: assume ipsec_setspidx never sleep */ 235 if (ipsec_setspidx(m, &spidx, 1) != 0) { 236 sp = NULL; 237 goto out; 238 } 239 240 /* 241 * We have to make an exact match here since the cached rule 242 * might have lower priority than a rule that would otherwise 243 * have matched the packet. 244 */ 245 if (memcmp(&pcbsp->sp_cache[dir].cacheidx, &spidx, 246 sizeof(spidx))) { 247 sp = NULL; 248 goto out; 249 } 250 } else { 251 /* 252 * The pcb is connected, and the L4 code is sure that: 253 * - outgoing side uses inp_[lf]addr 254 * - incoming side looks up policy after inpcb lookup 255 * and address pair is know to be stable. We do not need 256 * to generate spidx again, nor check the address match again. 257 * 258 * For IPv4/v6 SOCK_STREAM sockets, this assumptions holds 259 * and there are calls to ipsec_pcbconn() from in_pcbconnect(). 260 */ 261 } 262 263 sp->lastused = time_second; 264 KEY_SP_REF(sp); 265 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 266 "DP cause refcnt++:%d SP:%p\n", 267 key_sp_refcnt(sp), pcbsp->sp_cache[dir].cachesp); 268 out: 269 pserialize_read_exit(s); 270 return sp; 271 } 272 273 static int 274 ipsec_fillpcbcache(struct inpcbpolicy *pcbsp, struct mbuf *m, 275 struct secpolicy *sp, int dir) 276 { 277 278 KASSERT(IPSEC_DIR_IS_INOROUT(dir)); 279 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 280 KASSERT(inph_locked(pcbsp->sp_inph)); 281 282 pcbsp->sp_cache[dir].cachesp = NULL; 283 pcbsp->sp_cache[dir].cachehint = IPSEC_PCBHINT_UNKNOWN; 284 if (ipsec_setspidx(m, &pcbsp->sp_cache[dir].cacheidx, 1) != 0) { 285 return EINVAL; 286 } 287 pcbsp->sp_cache[dir].cachesp = sp; 288 if (pcbsp->sp_cache[dir].cachesp) { 289 /* 290 * If the PCB is connected, we can remember a hint to 291 * possibly short-circuit IPsec processing in other places. 292 */ 293 if (pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) { 294 switch (pcbsp->sp_cache[dir].cachesp->policy) { 295 case IPSEC_POLICY_NONE: 296 case IPSEC_POLICY_BYPASS: 297 pcbsp->sp_cache[dir].cachehint = 298 IPSEC_PCBHINT_NO; 299 break; 300 default: 301 pcbsp->sp_cache[dir].cachehint = 302 IPSEC_PCBHINT_YES; 303 } 304 } 305 } 306 pcbsp->sp_cache[dir].cachegen = ipsec_spdgen; 307 308 return 0; 309 } 310 311 static int 312 ipsec_invalpcbcache(struct inpcbpolicy *pcbsp, int dir) 313 { 314 int i; 315 316 KASSERT(inph_locked(pcbsp->sp_inph)); 317 318 for (i = IPSEC_DIR_INBOUND; i <= IPSEC_DIR_OUTBOUND; i++) { 319 if (dir != IPSEC_DIR_ANY && i != dir) 320 continue; 321 pcbsp->sp_cache[i].cachesp = NULL; 322 pcbsp->sp_cache[i].cachehint = IPSEC_PCBHINT_UNKNOWN; 323 pcbsp->sp_cache[i].cachegen = 0; 324 memset(&pcbsp->sp_cache[i].cacheidx, 0, 325 sizeof(pcbsp->sp_cache[i].cacheidx)); 326 } 327 return 0; 328 } 329 330 void 331 ipsec_pcbconn(struct inpcbpolicy *pcbsp) 332 { 333 334 KASSERT(inph_locked(pcbsp->sp_inph)); 335 336 pcbsp->sp_cacheflags |= IPSEC_PCBSP_CONNECTED; 337 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 338 } 339 340 void 341 ipsec_pcbdisconn(struct inpcbpolicy *pcbsp) 342 { 343 344 KASSERT(inph_locked(pcbsp->sp_inph)); 345 346 pcbsp->sp_cacheflags &= ~IPSEC_PCBSP_CONNECTED; 347 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 348 } 349 350 void 351 ipsec_invalpcbcacheall(void) 352 { 353 354 if (ipsec_spdgen == UINT_MAX) 355 ipsec_spdgen = 1; 356 else 357 ipsec_spdgen++; 358 } 359 360 /* 361 * Return a held reference to the default SP. 362 */ 363 static struct secpolicy * 364 key_get_default_sp(int af, const char *where, int tag) 365 { 366 struct secpolicy *sp; 367 368 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP from %s:%u\n", where, tag); 369 370 switch(af) { 371 case AF_INET: 372 sp = &ip4_def_policy; 373 break; 374 #ifdef INET6 375 case AF_INET6: 376 sp = &ip6_def_policy; 377 break; 378 #endif 379 default: 380 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 381 "unexpected protocol family %u\n", af); 382 return NULL; 383 } 384 385 if (sp->policy != IPSEC_POLICY_DISCARD && 386 sp->policy != IPSEC_POLICY_NONE) { 387 IPSECLOG(LOG_INFO, "fixed system default policy: %d->%d\n", 388 sp->policy, IPSEC_POLICY_NONE); 389 sp->policy = IPSEC_POLICY_NONE; 390 } 391 KEY_SP_REF(sp); 392 393 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP returns SP:%p (%u)\n", 394 sp, key_sp_refcnt(sp)); 395 return sp; 396 } 397 #define KEY_GET_DEFAULT_SP(af) \ 398 key_get_default_sp((af), __func__, __LINE__) 399 400 /* 401 * For OUTBOUND packet having a socket. Searching SPD for packet, 402 * and return a pointer to SP. 403 * OUT: NULL: no apropreate SP found, the following value is set to error. 404 * 0 : bypass 405 * EACCES : discard packet. 406 * ENOENT : ipsec_acquire() in progress, maybe. 407 * others : error occurred. 408 * others: a pointer to SP 409 * 410 * NOTE: IPv6 mapped address concern is implemented here. 411 */ 412 static struct secpolicy * 413 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb_hdr *inph, 414 int *error) 415 { 416 struct inpcbpolicy *pcbsp = NULL; 417 struct secpolicy *currsp = NULL; /* policy on socket */ 418 struct secpolicy *sp; 419 int af; 420 421 KASSERT(m != NULL); 422 KASSERT(inph != NULL); 423 KASSERT(error != NULL); 424 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 425 426 KASSERT(inph->inph_socket != NULL); 427 KASSERT(inph_locked(inph)); 428 429 /* XXX FIXME inpcb/in6pcb vs socket*/ 430 af = inph->inph_af; 431 KASSERTMSG(af == AF_INET || af == AF_INET6, 432 "unexpected protocol family %u", af); 433 434 KASSERT(inph->inph_sp != NULL); 435 /* If we have a cached entry, and if it is still valid, use it. */ 436 IPSEC_STATINC(IPSEC_STAT_SPDCACHELOOKUP); 437 currsp = ipsec_checkpcbcache(m, inph->inph_sp, dir); 438 if (currsp) { 439 *error = 0; 440 return currsp; 441 } 442 IPSEC_STATINC(IPSEC_STAT_SPDCACHEMISS); 443 444 switch (af) { 445 case AF_INET: { 446 struct inpcb *in4p = (struct inpcb *)inph; 447 /* set spidx in pcb */ 448 *error = ipsec4_setspidx_inpcb(m, in4p); 449 pcbsp = in4p->inp_sp; 450 break; 451 } 452 453 #if defined(INET6) 454 case AF_INET6: { 455 struct in6pcb *in6p = (struct in6pcb *)inph; 456 /* set spidx in pcb */ 457 *error = ipsec6_setspidx_in6pcb(m, in6p); 458 pcbsp = in6p->in6p_sp; 459 break; 460 } 461 #endif 462 default: 463 *error = EPFNOSUPPORT; 464 break; 465 } 466 if (*error) 467 return NULL; 468 469 KASSERT(pcbsp != NULL); 470 switch (dir) { 471 case IPSEC_DIR_INBOUND: 472 currsp = pcbsp->sp_in; 473 break; 474 case IPSEC_DIR_OUTBOUND: 475 currsp = pcbsp->sp_out; 476 break; 477 } 478 KASSERT(currsp != NULL); 479 480 if (pcbsp->priv) { /* when privilieged socket */ 481 switch (currsp->policy) { 482 case IPSEC_POLICY_BYPASS: 483 case IPSEC_POLICY_IPSEC: 484 KEY_SP_REF(currsp); 485 sp = currsp; 486 break; 487 488 case IPSEC_POLICY_ENTRUST: 489 /* look for a policy in SPD */ 490 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 491 if (sp == NULL) /* no SP found */ 492 sp = KEY_GET_DEFAULT_SP(af); 493 break; 494 495 default: 496 IPSECLOG(LOG_ERR, "Invalid policy for PCB %d\n", 497 currsp->policy); 498 *error = EINVAL; 499 return NULL; 500 } 501 } else { /* unpriv, SPD has policy */ 502 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 503 if (sp == NULL) { /* no SP found */ 504 switch (currsp->policy) { 505 case IPSEC_POLICY_BYPASS: 506 IPSECLOG(LOG_ERR, "Illegal policy for " 507 "non-priviliged defined %d\n", 508 currsp->policy); 509 *error = EINVAL; 510 return NULL; 511 512 case IPSEC_POLICY_ENTRUST: 513 sp = KEY_GET_DEFAULT_SP(af); 514 break; 515 516 case IPSEC_POLICY_IPSEC: 517 KEY_SP_REF(currsp); 518 sp = currsp; 519 break; 520 521 default: 522 IPSECLOG(LOG_ERR, "Invalid policy for " 523 "PCB %d\n", currsp->policy); 524 *error = EINVAL; 525 return NULL; 526 } 527 } 528 } 529 KASSERTMSG(sp != NULL, "null SP (priv %u policy %u", pcbsp->priv, 530 currsp->policy); 531 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 532 "DP (priv %u policy %u) allocates SP:%p (refcnt %u)\n", 533 pcbsp->priv, currsp->policy, sp, key_sp_refcnt(sp)); 534 ipsec_fillpcbcache(pcbsp, m, sp, dir); 535 return sp; 536 } 537 538 /* 539 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 540 * and return a pointer to SP. 541 * OUT: positive: a pointer to the entry for security policy leaf matched. 542 * NULL: no apropreate SP found, the following value is set to error. 543 * 0 : bypass 544 * EACCES : discard packet. 545 * ENOENT : ipsec_acquire() in progress, maybe. 546 * others : error occurred. 547 */ 548 struct secpolicy * 549 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 550 { 551 struct secpolicyindex spidx; 552 struct secpolicy *sp; 553 554 KASSERT(m != NULL); 555 KASSERT(error != NULL); 556 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 557 558 sp = NULL; 559 560 /* Make an index to look for a policy. */ 561 *error = ipsec_setspidx(m, &spidx, (flag & IP_FORWARDING) ? 0 : 1); 562 if (*error != 0) { 563 IPSECLOG(LOG_DEBUG, "setpidx failed, dir %u flag %u\n", dir, flag); 564 memset(&spidx, 0, sizeof (spidx)); 565 return NULL; 566 } 567 568 spidx.dir = dir; 569 570 if (key_havesp(dir)) { 571 sp = KEY_LOOKUP_SP_BYSPIDX(&spidx, dir); 572 } 573 574 if (sp == NULL) /* no SP found, use system default */ 575 sp = KEY_GET_DEFAULT_SP(spidx.dst.sa.sa_family); 576 KASSERT(sp != NULL); 577 return sp; 578 } 579 580 struct secpolicy * 581 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 582 struct inpcb *inp) 583 { 584 struct secpolicy *sp; 585 586 *error = 0; 587 588 if (inp == NULL) { 589 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 590 } else { 591 KASSERT(inp->inp_socket != NULL); 592 sp = ipsec_getpolicybysock(m, dir, (struct inpcb_hdr *)inp, error); 593 } 594 if (sp == NULL) { 595 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 596 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 597 return NULL; 598 } 599 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 600 switch (sp->policy) { 601 case IPSEC_POLICY_ENTRUST: 602 default: 603 printf("%s: invalid policy %u\n", __func__, sp->policy); 604 /* fall thru... */ 605 case IPSEC_POLICY_DISCARD: 606 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 607 *error = -EINVAL; /* packet is discarded by caller */ 608 break; 609 case IPSEC_POLICY_BYPASS: 610 case IPSEC_POLICY_NONE: 611 KEY_SP_UNREF(&sp); 612 sp = NULL; /* NB: force NULL result */ 613 break; 614 case IPSEC_POLICY_IPSEC: 615 KASSERT(sp->req != NULL); 616 break; 617 } 618 if (*error != 0) { 619 KEY_SP_UNREF(&sp); 620 sp = NULL; 621 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 622 } 623 return sp; 624 } 625 626 int 627 ipsec4_output(struct mbuf *m, struct inpcb *inp, int flags, 628 u_long *mtu, bool *natt_frag, bool *done) 629 { 630 struct secpolicy *sp = NULL; 631 int error, s; 632 633 /* 634 * Check the security policy (SP) for the packet and, if required, 635 * do IPsec-related processing. There are two cases here; the first 636 * time a packet is sent through it will be untagged and handled by 637 * ipsec4_checkpolicy(). If the packet is resubmitted to ip_output 638 * (e.g. after AH, ESP, etc. processing), there will be a tag to 639 * bypass the lookup and related policy checking. 640 */ 641 if (ipsec_outdone(m)) { 642 return 0; 643 } 644 s = splsoftnet(); 645 if (inp && ipsec_pcb_skip_ipsec(inp->inp_sp, IPSEC_DIR_OUTBOUND)) { 646 splx(s); 647 return 0; 648 } 649 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, inp); 650 651 /* 652 * There are four return cases: 653 * sp != NULL apply IPsec policy 654 * sp == NULL, error == 0 no IPsec handling needed 655 * sp == NULL, error == -EINVAL discard packet w/o error 656 * sp == NULL, error != 0 discard packet, report error 657 */ 658 if (sp == NULL) { 659 splx(s); 660 if (error) { 661 /* 662 * Hack: -EINVAL is used to signal that a packet 663 * should be silently discarded. This is typically 664 * because we asked key management for an SA and 665 * it was delayed (e.g. kicked up to IKE). 666 */ 667 if (error == -EINVAL) 668 error = 0; 669 m_freem(m); 670 *done = true; 671 return error; 672 } 673 /* No IPsec processing for this packet. */ 674 return 0; 675 } 676 677 /* 678 * Do delayed checksums now because we send before 679 * this is done in the normal processing path. 680 */ 681 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 682 in_delayed_cksum(m); 683 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 684 } 685 686 { 687 u_long _mtu = 0; 688 689 /* Note: callee frees mbuf */ 690 error = ipsec4_process_packet(m, sp->req, &_mtu); 691 692 if (error == 0 && _mtu != 0) { 693 /* 694 * NAT-T ESP fragmentation: do not do IPSec processing 695 * now, we will do it on each fragmented packet. 696 */ 697 *mtu = _mtu; 698 *natt_frag = true; 699 KEY_SP_UNREF(&sp); 700 splx(s); 701 return 0; 702 } 703 } 704 /* 705 * Preserve KAME behaviour: ENOENT can be returned 706 * when an SA acquire is in progress. Don't propagate 707 * this to user-level; it confuses applications. 708 * 709 * XXX this will go away when the SADB is redone. 710 */ 711 if (error == ENOENT) 712 error = 0; 713 KEY_SP_UNREF(&sp); 714 splx(s); 715 *done = true; 716 return error; 717 } 718 719 int 720 ipsec4_input(struct mbuf *m, int flags) 721 { 722 struct secpolicy *sp; 723 int error, s; 724 725 s = splsoftnet(); 726 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 727 if (sp == NULL) { 728 splx(s); 729 return EINVAL; 730 } 731 732 /* 733 * Check security policy against packet attributes. 734 */ 735 error = ipsec_in_reject(sp, m); 736 KEY_SP_UNREF(&sp); 737 splx(s); 738 if (error) { 739 return error; 740 } 741 742 if (flags == 0) { 743 /* We are done. */ 744 return 0; 745 } 746 747 /* 748 * Peek at the outbound SP for this packet to determine if 749 * it is a Fast Forward candidate. 750 */ 751 s = splsoftnet(); 752 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, NULL); 753 if (sp != NULL) { 754 m->m_flags &= ~M_CANFASTFWD; 755 KEY_SP_UNREF(&sp); 756 } 757 splx(s); 758 return 0; 759 } 760 761 int 762 ipsec4_forward(struct mbuf *m, int *destmtu) 763 { 764 /* 765 * If the packet is routed over IPsec tunnel, tell the 766 * originator the tunnel MTU. 767 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 768 * XXX quickhack!!! 769 */ 770 struct secpolicy *sp; 771 size_t ipsechdr; 772 int error; 773 774 sp = ipsec4_getpolicybyaddr(m, 775 IPSEC_DIR_OUTBOUND, IP_FORWARDING, &error); 776 if (sp == NULL) { 777 return EINVAL; 778 } 779 780 /* Count IPsec header size. */ 781 ipsechdr = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, NULL); 782 783 /* 784 * Find the correct route for outer IPv4 header, compute tunnel MTU. 785 */ 786 if (sp->req) { 787 struct secasvar *sav; 788 789 sav = ipsec_lookup_sa(sp->req, m); 790 if (sav != NULL) { 791 struct route *ro; 792 struct rtentry *rt; 793 794 ro = &sav->sah->sa_route; 795 rt = rtcache_validate(ro); 796 if (rt && rt->rt_ifp) { 797 *destmtu = rt->rt_rmx.rmx_mtu ? 798 rt->rt_rmx.rmx_mtu : rt->rt_ifp->if_mtu; 799 *destmtu -= ipsechdr; 800 } 801 rtcache_unref(rt, ro); 802 KEY_SA_UNREF(&sav); 803 } 804 } 805 KEY_SP_UNREF(&sp); 806 return 0; 807 } 808 809 #ifdef INET6 810 struct secpolicy * 811 ipsec6_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 812 struct in6pcb *in6p) 813 { 814 struct secpolicy *sp; 815 816 *error = 0; 817 818 if (in6p == NULL) { 819 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 820 } else { 821 KASSERT(in6p->in6p_socket != NULL); 822 sp = ipsec_getpolicybysock(m, dir, (struct inpcb_hdr *)in6p, error); 823 } 824 if (sp == NULL) { 825 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 826 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 827 return NULL; 828 } 829 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 830 switch (sp->policy) { 831 case IPSEC_POLICY_ENTRUST: 832 default: 833 printf("%s: invalid policy %u\n", __func__, sp->policy); 834 /* fall thru... */ 835 case IPSEC_POLICY_DISCARD: 836 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 837 *error = -EINVAL; /* packet is discarded by caller */ 838 break; 839 case IPSEC_POLICY_BYPASS: 840 case IPSEC_POLICY_NONE: 841 KEY_SP_UNREF(&sp); 842 sp = NULL; /* NB: force NULL result */ 843 break; 844 case IPSEC_POLICY_IPSEC: 845 KASSERT(sp->req != NULL); 846 break; 847 } 848 if (*error != 0) { 849 KEY_SP_UNREF(&sp); 850 sp = NULL; 851 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 852 } 853 return sp; 854 } 855 #endif /* INET6 */ 856 857 static int 858 ipsec4_setspidx_inpcb(struct mbuf *m, struct inpcb *pcb) 859 { 860 int error; 861 862 KASSERT(pcb != NULL); 863 KASSERT(pcb->inp_sp != NULL); 864 KASSERT(pcb->inp_sp->sp_out != NULL); 865 KASSERT(pcb->inp_sp->sp_in != NULL); 866 867 error = ipsec_setspidx(m, &pcb->inp_sp->sp_in->spidx, 1); 868 if (error == 0) { 869 pcb->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 870 pcb->inp_sp->sp_out->spidx = pcb->inp_sp->sp_in->spidx; 871 pcb->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 872 } else { 873 memset(&pcb->inp_sp->sp_in->spidx, 0, 874 sizeof(pcb->inp_sp->sp_in->spidx)); 875 memset(&pcb->inp_sp->sp_out->spidx, 0, 876 sizeof(pcb->inp_sp->sp_in->spidx)); 877 } 878 return error; 879 } 880 881 #ifdef INET6 882 static int 883 ipsec6_setspidx_in6pcb(struct mbuf *m, struct in6pcb *pcb) 884 { 885 struct secpolicyindex *spidx; 886 int error; 887 888 KASSERT(pcb != NULL); 889 KASSERT(pcb->in6p_sp != NULL); 890 KASSERT(pcb->in6p_sp->sp_out != NULL); 891 KASSERT(pcb->in6p_sp->sp_in != NULL); 892 893 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 894 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 895 896 spidx = &pcb->in6p_sp->sp_in->spidx; 897 error = ipsec_setspidx(m, spidx, 1); 898 if (error) 899 goto bad; 900 spidx->dir = IPSEC_DIR_INBOUND; 901 902 spidx = &pcb->in6p_sp->sp_out->spidx; 903 error = ipsec_setspidx(m, spidx, 1); 904 if (error) 905 goto bad; 906 spidx->dir = IPSEC_DIR_OUTBOUND; 907 908 return 0; 909 910 bad: 911 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 912 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 913 return error; 914 } 915 #endif 916 917 /* 918 * configure security policy index (src/dst/proto/sport/dport) 919 * by looking at the content of mbuf. 920 * the caller is responsible for error recovery (like clearing up spidx). 921 */ 922 static int 923 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 924 { 925 struct ip *ip = NULL; 926 struct ip ipbuf; 927 u_int v; 928 struct mbuf *n; 929 int len; 930 int error; 931 932 KASSERT(m != NULL); 933 934 /* 935 * validate m->m_pkthdr.len. we see incorrect length if we 936 * mistakenly call this function with inconsistent mbuf chain 937 * (like 4.4BSD tcp/udp processing). XXX should we panic here? 938 */ 939 len = 0; 940 for (n = m; n; n = n->m_next) 941 len += n->m_len; 942 if (m->m_pkthdr.len != len) { 943 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 944 "total of m_len(%d) != pkthdr.len(%d), ignored.\n", 945 len, m->m_pkthdr.len); 946 return EINVAL; 947 } 948 949 if (m->m_pkthdr.len < sizeof(struct ip)) { 950 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 951 "pkthdr.len(%d) < sizeof(struct ip), ignored.\n", 952 m->m_pkthdr.len); 953 return EINVAL; 954 } 955 956 if (m->m_len >= sizeof(*ip)) 957 ip = mtod(m, struct ip *); 958 else { 959 m_copydata(m, 0, sizeof(ipbuf), &ipbuf); 960 ip = &ipbuf; 961 } 962 v = ip->ip_v; 963 switch (v) { 964 case 4: 965 error = ipsec4_setspidx_ipaddr(m, spidx); 966 if (error) 967 return error; 968 ipsec4_get_ulp(m, spidx, needport); 969 return 0; 970 #ifdef INET6 971 case 6: 972 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 973 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 974 "pkthdr.len(%d) < sizeof(struct ip6_hdr), " 975 "ignored.\n", m->m_pkthdr.len); 976 return EINVAL; 977 } 978 error = ipsec6_setspidx_ipaddr(m, spidx); 979 if (error) 980 return error; 981 ipsec6_get_ulp(m, spidx, needport); 982 return 0; 983 #endif 984 default: 985 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 986 "unknown IP version %u, ignored.\n", v); 987 return EINVAL; 988 } 989 } 990 991 static void 992 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 993 { 994 u_int8_t nxt; 995 int off; 996 997 /* sanity check */ 998 KASSERT(m != NULL); 999 KASSERTMSG(m->m_pkthdr.len >= sizeof(struct ip), "packet too short"); 1000 1001 /* NB: ip_input() flips it into host endian XXX need more checking */ 1002 if (m->m_len >= sizeof(struct ip)) { 1003 struct ip *ip = mtod(m, struct ip *); 1004 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 1005 goto done; 1006 off = ip->ip_hl << 2; 1007 nxt = ip->ip_p; 1008 } else { 1009 struct ip ih; 1010 1011 m_copydata(m, 0, sizeof (struct ip), &ih); 1012 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 1013 goto done; 1014 off = ih.ip_hl << 2; 1015 nxt = ih.ip_p; 1016 } 1017 1018 while (off < m->m_pkthdr.len) { 1019 struct ip6_ext ip6e; 1020 struct tcphdr th; 1021 struct udphdr uh; 1022 struct icmp icmph; 1023 1024 switch (nxt) { 1025 case IPPROTO_TCP: 1026 spidx->ul_proto = nxt; 1027 if (!needport) 1028 goto done_proto; 1029 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1030 goto done; 1031 m_copydata(m, off, sizeof (th), &th); 1032 spidx->src.sin.sin_port = th.th_sport; 1033 spidx->dst.sin.sin_port = th.th_dport; 1034 return; 1035 case IPPROTO_UDP: 1036 spidx->ul_proto = nxt; 1037 if (!needport) 1038 goto done_proto; 1039 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1040 goto done; 1041 m_copydata(m, off, sizeof (uh), &uh); 1042 spidx->src.sin.sin_port = uh.uh_sport; 1043 spidx->dst.sin.sin_port = uh.uh_dport; 1044 return; 1045 case IPPROTO_AH: 1046 if (m->m_pkthdr.len > off + sizeof(ip6e)) 1047 goto done; 1048 /* XXX sigh, this works but is totally bogus */ 1049 m_copydata(m, off, sizeof(ip6e), &ip6e); 1050 off += (ip6e.ip6e_len + 2) << 2; 1051 nxt = ip6e.ip6e_nxt; 1052 break; 1053 case IPPROTO_ICMP: 1054 spidx->ul_proto = nxt; 1055 if (off + sizeof(struct icmp) > m->m_pkthdr.len) 1056 return; 1057 m_copydata(m, off, sizeof(icmph), &icmph); 1058 ((struct sockaddr_in *)&spidx->src)->sin_port = 1059 htons((uint16_t)icmph.icmp_type); 1060 ((struct sockaddr_in *)&spidx->dst)->sin_port = 1061 htons((uint16_t)icmph.icmp_code); 1062 return; 1063 default: 1064 /* XXX intermediate headers??? */ 1065 spidx->ul_proto = nxt; 1066 goto done_proto; 1067 } 1068 } 1069 done: 1070 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1071 done_proto: 1072 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 1073 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 1074 } 1075 1076 /* assumes that m is sane */ 1077 static int 1078 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1079 { 1080 static const struct sockaddr_in template = { 1081 sizeof (struct sockaddr_in), 1082 AF_INET, 1083 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 1084 }; 1085 1086 spidx->src.sin = template; 1087 spidx->dst.sin = template; 1088 1089 if (m->m_len < sizeof (struct ip)) { 1090 m_copydata(m, offsetof(struct ip, ip_src), 1091 sizeof(struct in_addr), &spidx->src.sin.sin_addr); 1092 m_copydata(m, offsetof(struct ip, ip_dst), 1093 sizeof(struct in_addr), &spidx->dst.sin.sin_addr); 1094 } else { 1095 struct ip *ip = mtod(m, struct ip *); 1096 spidx->src.sin.sin_addr = ip->ip_src; 1097 spidx->dst.sin.sin_addr = ip->ip_dst; 1098 } 1099 1100 spidx->prefs = sizeof(struct in_addr) << 3; 1101 spidx->prefd = sizeof(struct in_addr) << 3; 1102 1103 return 0; 1104 } 1105 1106 #ifdef INET6 1107 static void 1108 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, 1109 int needport) 1110 { 1111 int off, nxt; 1112 struct tcphdr th; 1113 struct udphdr uh; 1114 struct icmp6_hdr icmph; 1115 1116 KASSERT(m != NULL); 1117 1118 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1119 kdebug_mbuf(__func__, m); 1120 } 1121 1122 /* set default */ 1123 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1124 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 1125 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 1126 1127 nxt = -1; 1128 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 1129 if (off < 0 || m->m_pkthdr.len < off) 1130 return; 1131 1132 switch (nxt) { 1133 case IPPROTO_TCP: 1134 spidx->ul_proto = nxt; 1135 if (!needport) 1136 break; 1137 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1138 break; 1139 m_copydata(m, off, sizeof(th), &th); 1140 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 1141 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 1142 break; 1143 case IPPROTO_UDP: 1144 spidx->ul_proto = nxt; 1145 if (!needport) 1146 break; 1147 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1148 break; 1149 m_copydata(m, off, sizeof(uh), &uh); 1150 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 1151 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 1152 break; 1153 case IPPROTO_ICMPV6: 1154 spidx->ul_proto = nxt; 1155 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 1156 break; 1157 m_copydata(m, off, sizeof(icmph), &icmph); 1158 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 1159 htons((uint16_t)icmph.icmp6_type); 1160 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 1161 htons((uint16_t)icmph.icmp6_code); 1162 break; 1163 default: 1164 /* XXX intermediate headers??? */ 1165 spidx->ul_proto = nxt; 1166 break; 1167 } 1168 } 1169 1170 /* assumes that m is sane */ 1171 static int 1172 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1173 { 1174 struct ip6_hdr *ip6 = NULL; 1175 struct ip6_hdr ip6buf; 1176 struct sockaddr_in6 *sin6; 1177 1178 if (m->m_len >= sizeof(*ip6)) 1179 ip6 = mtod(m, struct ip6_hdr *); 1180 else { 1181 m_copydata(m, 0, sizeof(ip6buf), &ip6buf); 1182 ip6 = &ip6buf; 1183 } 1184 1185 sin6 = (struct sockaddr_in6 *)&spidx->src; 1186 memset(sin6, 0, sizeof(*sin6)); 1187 sin6->sin6_family = AF_INET6; 1188 sin6->sin6_len = sizeof(struct sockaddr_in6); 1189 memcpy(&sin6->sin6_addr, &ip6->ip6_src, sizeof(ip6->ip6_src)); 1190 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 1191 sin6->sin6_addr.s6_addr16[1] = 0; 1192 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 1193 } 1194 spidx->prefs = sizeof(struct in6_addr) << 3; 1195 1196 sin6 = (struct sockaddr_in6 *)&spidx->dst; 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_dst, sizeof(ip6->ip6_dst)); 1201 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 1202 sin6->sin6_addr.s6_addr16[1] = 0; 1203 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 1204 } 1205 spidx->prefd = sizeof(struct in6_addr) << 3; 1206 1207 return 0; 1208 } 1209 #endif 1210 1211 static void 1212 ipsec_delpcbpolicy(struct inpcbpolicy *p) 1213 { 1214 1215 kmem_intr_free(p, sizeof(*p)); 1216 } 1217 1218 /* initialize policy in PCB */ 1219 int 1220 ipsec_init_policy(struct socket *so, struct inpcbpolicy **policy) 1221 { 1222 struct inpcbpolicy *new; 1223 1224 KASSERT(so != NULL); 1225 KASSERT(policy != NULL); 1226 1227 new = kmem_intr_zalloc(sizeof(*new), KM_NOSLEEP); 1228 if (new == NULL) { 1229 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1230 return ENOBUFS; 1231 } 1232 1233 if (IPSEC_PRIVILEGED_SO(so)) 1234 new->priv = 1; 1235 else 1236 new->priv = 0; 1237 1238 /* 1239 * Set dummy SPs. Actual SPs will be allocated later if needed. 1240 */ 1241 new->sp_in = &ipsec_dummy_sp; 1242 new->sp_out = &ipsec_dummy_sp; 1243 1244 *policy = new; 1245 1246 return 0; 1247 } 1248 1249 #if 0 /* unused */ 1250 /* copy old ipsec policy into new */ 1251 int 1252 ipsec_copy_policy(const struct inpcbpolicy *old, struct inpcbpolicy *new) 1253 { 1254 struct secpolicy *sp; 1255 1256 sp = ipsec_deepcopy_policy(old->sp_in); 1257 if (sp) { 1258 KEY_SP_UNREF(&new->sp_in); 1259 new->sp_in = sp; 1260 } else 1261 return ENOBUFS; 1262 1263 sp = ipsec_deepcopy_policy(old->sp_out); 1264 if (sp) { 1265 KEY_SP_UNREF(&new->sp_out); 1266 new->sp_out = sp; 1267 } else 1268 return ENOBUFS; 1269 1270 new->priv = old->priv; 1271 1272 return 0; 1273 } 1274 1275 /* deep-copy a policy in PCB */ 1276 static struct secpolicy * 1277 ipsec_deepcopy_policy(const struct secpolicy *src) 1278 { 1279 struct ipsecrequest *newchain = NULL; 1280 const struct ipsecrequest *p; 1281 struct ipsecrequest **q; 1282 struct secpolicy *dst; 1283 1284 if (src == NULL) 1285 return NULL; 1286 dst = KEY_NEWSP(); 1287 if (dst == NULL) 1288 return NULL; 1289 1290 /* 1291 * deep-copy IPsec request chain. This is required since struct 1292 * ipsecrequest is not reference counted. 1293 */ 1294 q = &newchain; 1295 for (p = src->req; p; p = p->next) { 1296 *q = kmem_zalloc(sizeof(**q), KM_SLEEP); 1297 (*q)->next = NULL; 1298 1299 (*q)->saidx.proto = p->saidx.proto; 1300 (*q)->saidx.mode = p->saidx.mode; 1301 (*q)->level = p->level; 1302 (*q)->saidx.reqid = p->saidx.reqid; 1303 1304 memcpy(&(*q)->saidx.src, &p->saidx.src, sizeof((*q)->saidx.src)); 1305 memcpy(&(*q)->saidx.dst, &p->saidx.dst, sizeof((*q)->saidx.dst)); 1306 1307 (*q)->sp = dst; 1308 1309 q = &((*q)->next); 1310 } 1311 1312 dst->req = newchain; 1313 dst->state = src->state; 1314 dst->policy = src->policy; 1315 /* do not touch the refcnt fields */ 1316 1317 return dst; 1318 } 1319 #endif 1320 1321 static void 1322 ipsec_destroy_policy(struct secpolicy *sp) 1323 { 1324 1325 if (sp == &ipsec_dummy_sp) 1326 ; /* It's dummy. No need to free it. */ 1327 else { 1328 /* 1329 * We cannot destroy here because it can be called in 1330 * softint. So mark the SP as DEAD and let the timer 1331 * destroy it. See key_timehandler_spd. 1332 */ 1333 sp->state = IPSEC_SPSTATE_DEAD; 1334 } 1335 } 1336 1337 /* set policy and ipsec request if present. */ 1338 static int 1339 ipsec_set_policy( 1340 struct secpolicy **policy, 1341 int optname, 1342 const void *request, 1343 size_t len, 1344 kauth_cred_t cred 1345 ) 1346 { 1347 const struct sadb_x_policy *xpl; 1348 struct secpolicy *newsp = NULL, *oldsp; 1349 int error; 1350 1351 KASSERT(!cpu_softintr_p()); 1352 1353 /* sanity check. */ 1354 if (policy == NULL || *policy == NULL || request == NULL) 1355 return EINVAL; 1356 if (len < sizeof(*xpl)) 1357 return EINVAL; 1358 xpl = (const struct sadb_x_policy *)request; 1359 1360 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1361 kdebug_sadb_xpolicy("set passed policy", request); 1362 } 1363 1364 /* check policy type */ 1365 /* ipsec_set_policy() accepts IPSEC, ENTRUST and BYPASS. */ 1366 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 1367 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1368 return EINVAL; 1369 1370 /* check privileged socket */ 1371 if (xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1372 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPSEC, 1373 KAUTH_REQ_NETWORK_IPSEC_BYPASS, NULL, NULL, NULL); 1374 if (error) 1375 return (error); 1376 } 1377 1378 /* allocation new SP entry */ 1379 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1380 return error; 1381 1382 key_init_sp(newsp); 1383 newsp->created = time_uptime; 1384 /* Insert the global list for SPs for sockets */ 1385 key_socksplist_add(newsp); 1386 1387 /* clear old SP and set new SP */ 1388 oldsp = *policy; 1389 *policy = newsp; 1390 ipsec_destroy_policy(oldsp); 1391 1392 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1393 printf("%s: new policy\n", __func__); 1394 kdebug_secpolicy(newsp); 1395 } 1396 1397 return 0; 1398 } 1399 1400 static int 1401 ipsec_get_policy(struct secpolicy *policy, struct mbuf **mp) 1402 { 1403 1404 /* sanity check. */ 1405 if (policy == NULL || mp == NULL) 1406 return EINVAL; 1407 1408 *mp = key_sp2msg(policy, M_NOWAIT); 1409 if (!*mp) { 1410 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1411 return ENOBUFS; 1412 } 1413 1414 (*mp)->m_type = MT_DATA; 1415 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1416 kdebug_mbuf(__func__, *mp); 1417 } 1418 1419 return 0; 1420 } 1421 1422 int 1423 ipsec4_set_policy(struct inpcb *inp, int optname, const void *request, 1424 size_t len, kauth_cred_t cred) 1425 { 1426 const struct sadb_x_policy *xpl; 1427 struct secpolicy **policy; 1428 1429 KASSERT(!cpu_softintr_p()); 1430 KASSERT(inp != NULL); 1431 KASSERT(inp_locked(inp)); 1432 KASSERT(request != NULL); 1433 1434 if (len < sizeof(*xpl)) 1435 return EINVAL; 1436 xpl = (const struct sadb_x_policy *)request; 1437 1438 KASSERT(inp->inp_sp != NULL); 1439 1440 /* select direction */ 1441 switch (xpl->sadb_x_policy_dir) { 1442 case IPSEC_DIR_INBOUND: 1443 policy = &inp->inp_sp->sp_in; 1444 break; 1445 case IPSEC_DIR_OUTBOUND: 1446 policy = &inp->inp_sp->sp_out; 1447 break; 1448 default: 1449 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1450 xpl->sadb_x_policy_dir); 1451 return EINVAL; 1452 } 1453 1454 return ipsec_set_policy(policy, optname, request, len, cred); 1455 } 1456 1457 int 1458 ipsec4_get_policy(struct inpcb *inp, const void *request, size_t len, 1459 struct mbuf **mp) 1460 { 1461 const struct sadb_x_policy *xpl; 1462 struct secpolicy *policy; 1463 1464 /* sanity check. */ 1465 if (inp == NULL || request == NULL || mp == NULL) 1466 return EINVAL; 1467 KASSERT(inp->inp_sp != NULL); 1468 if (len < sizeof(*xpl)) 1469 return EINVAL; 1470 xpl = (const struct sadb_x_policy *)request; 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_get_policy(policy, mp); 1487 } 1488 1489 /* delete policy in PCB */ 1490 int 1491 ipsec4_delete_pcbpolicy(struct inpcb *inp) 1492 { 1493 1494 KASSERT(inp != NULL); 1495 1496 if (inp->inp_sp == NULL) 1497 return 0; 1498 1499 if (inp->inp_sp->sp_in != NULL) 1500 ipsec_destroy_policy(inp->inp_sp->sp_in); 1501 1502 if (inp->inp_sp->sp_out != NULL) 1503 ipsec_destroy_policy(inp->inp_sp->sp_out); 1504 1505 ipsec_invalpcbcache(inp->inp_sp, IPSEC_DIR_ANY); 1506 1507 ipsec_delpcbpolicy(inp->inp_sp); 1508 inp->inp_sp = NULL; 1509 1510 return 0; 1511 } 1512 1513 #ifdef INET6 1514 int 1515 ipsec6_set_policy(struct in6pcb *in6p, int optname, const void *request, 1516 size_t len, kauth_cred_t cred) 1517 { 1518 const struct sadb_x_policy *xpl; 1519 struct secpolicy **policy; 1520 1521 KASSERT(!cpu_softintr_p()); 1522 KASSERT(in6p_locked(in6p)); 1523 1524 /* sanity check. */ 1525 if (in6p == NULL || request == NULL) 1526 return EINVAL; 1527 if (len < sizeof(*xpl)) 1528 return EINVAL; 1529 xpl = (const struct sadb_x_policy *)request; 1530 1531 /* select direction */ 1532 switch (xpl->sadb_x_policy_dir) { 1533 case IPSEC_DIR_INBOUND: 1534 policy = &in6p->in6p_sp->sp_in; 1535 break; 1536 case IPSEC_DIR_OUTBOUND: 1537 policy = &in6p->in6p_sp->sp_out; 1538 break; 1539 default: 1540 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1541 xpl->sadb_x_policy_dir); 1542 return EINVAL; 1543 } 1544 1545 return ipsec_set_policy(policy, optname, request, len, cred); 1546 } 1547 1548 int 1549 ipsec6_get_policy(struct in6pcb *in6p, const void *request, size_t len, 1550 struct mbuf **mp) 1551 { 1552 const struct sadb_x_policy *xpl; 1553 struct secpolicy *policy; 1554 1555 /* sanity check. */ 1556 if (in6p == NULL || request == NULL || mp == NULL) 1557 return EINVAL; 1558 KASSERT(in6p->in6p_sp != NULL); 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_get_policy(policy, mp); 1578 } 1579 1580 int 1581 ipsec6_delete_pcbpolicy(struct in6pcb *in6p) 1582 { 1583 1584 KASSERT(in6p != NULL); 1585 1586 if (in6p->in6p_sp == NULL) 1587 return 0; 1588 1589 if (in6p->in6p_sp->sp_in != NULL) 1590 ipsec_destroy_policy(in6p->in6p_sp->sp_in); 1591 1592 if (in6p->in6p_sp->sp_out != NULL) 1593 ipsec_destroy_policy(in6p->in6p_sp->sp_out); 1594 1595 ipsec_invalpcbcache(in6p->in6p_sp, IPSEC_DIR_ANY); 1596 1597 ipsec_delpcbpolicy(in6p->in6p_sp); 1598 in6p->in6p_sp = NULL; 1599 1600 return 0; 1601 } 1602 #endif 1603 1604 /* 1605 * return current level. 1606 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1607 */ 1608 u_int 1609 ipsec_get_reqlevel(const struct ipsecrequest *isr) 1610 { 1611 u_int level = 0; 1612 u_int esp_trans_deflev, esp_net_deflev; 1613 u_int ah_trans_deflev, ah_net_deflev; 1614 1615 KASSERT(isr != NULL); 1616 KASSERT(isr->sp != NULL); 1617 KASSERTMSG( 1618 isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1619 "af family mismatch, src %u, dst %u", 1620 isr->sp->spidx.src.sa.sa_family, isr->sp->spidx.dst.sa.sa_family); 1621 1622 /* XXX note that we have ipseclog() expanded here - code sync issue */ 1623 #define IPSEC_CHECK_DEFAULT(lev) \ 1624 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1625 && (lev) != IPSEC_LEVEL_UNIQUE) ? \ 1626 (ipsec_debug ? log(LOG_INFO, "fixed system default level " #lev \ 1627 ":%d->%d\n", (lev), IPSEC_LEVEL_REQUIRE) : (void)0), \ 1628 (lev) = IPSEC_LEVEL_REQUIRE, (lev) \ 1629 : (lev)) 1630 1631 /* set default level */ 1632 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1633 #ifdef INET 1634 case AF_INET: 1635 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_trans_deflev); 1636 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_net_deflev); 1637 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_trans_deflev); 1638 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_net_deflev); 1639 break; 1640 #endif 1641 #ifdef INET6 1642 case AF_INET6: 1643 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_trans_deflev); 1644 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_net_deflev); 1645 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_trans_deflev); 1646 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_net_deflev); 1647 break; 1648 #endif /* INET6 */ 1649 default: 1650 panic("%s: unknown af %u", __func__, 1651 isr->sp->spidx.src.sa.sa_family); 1652 } 1653 1654 #undef IPSEC_CHECK_DEFAULT 1655 1656 /* set level */ 1657 switch (isr->level) { 1658 case IPSEC_LEVEL_DEFAULT: 1659 switch (isr->saidx.proto) { 1660 case IPPROTO_ESP: 1661 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1662 level = esp_net_deflev; 1663 else 1664 level = esp_trans_deflev; 1665 break; 1666 case IPPROTO_AH: 1667 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1668 level = ah_net_deflev; 1669 else 1670 level = ah_trans_deflev; 1671 break; 1672 case IPPROTO_IPCOMP: 1673 /* 1674 * we don't really care, as IPcomp document says that 1675 * we shouldn't compress small packets 1676 */ 1677 level = IPSEC_LEVEL_USE; 1678 break; 1679 default: 1680 panic("%s: Illegal protocol defined %u", __func__, 1681 isr->saidx.proto); 1682 } 1683 break; 1684 1685 case IPSEC_LEVEL_USE: 1686 case IPSEC_LEVEL_REQUIRE: 1687 level = isr->level; 1688 break; 1689 case IPSEC_LEVEL_UNIQUE: 1690 level = IPSEC_LEVEL_REQUIRE; 1691 break; 1692 1693 default: 1694 panic("%s: Illegal IPsec level %u", __func__, isr->level); 1695 } 1696 1697 return level; 1698 } 1699 1700 /* 1701 * Check security policy requirements against the actual 1702 * packet contents. Return one if the packet should be 1703 * reject as "invalid"; otherwiser return zero to have the 1704 * packet treated as "valid". 1705 * 1706 * OUT: 1707 * 0: valid 1708 * 1: invalid 1709 */ 1710 int 1711 ipsec_in_reject(const struct secpolicy *sp, const struct mbuf *m) 1712 { 1713 struct ipsecrequest *isr; 1714 1715 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1716 printf("%s: using SP\n", __func__); 1717 kdebug_secpolicy(sp); 1718 } 1719 1720 /* check policy */ 1721 switch (sp->policy) { 1722 case IPSEC_POLICY_DISCARD: 1723 return 1; 1724 case IPSEC_POLICY_BYPASS: 1725 case IPSEC_POLICY_NONE: 1726 return 0; 1727 } 1728 1729 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1730 "invalid policy %u", sp->policy); 1731 1732 /* XXX should compare policy against ipsec header history */ 1733 1734 for (isr = sp->req; isr != NULL; isr = isr->next) { 1735 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1736 continue; 1737 switch (isr->saidx.proto) { 1738 case IPPROTO_ESP: 1739 if ((m->m_flags & M_DECRYPTED) == 0) { 1740 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1741 "ESP m_flags:%x\n", m->m_flags); 1742 return 1; 1743 } 1744 break; 1745 case IPPROTO_AH: 1746 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1747 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1748 "AH m_flags:%x\n", m->m_flags); 1749 return 1; 1750 } 1751 break; 1752 case IPPROTO_IPCOMP: 1753 /* 1754 * we don't really care, as IPcomp document 1755 * says that we shouldn't compress small 1756 * packets, IPComp policy should always be 1757 * treated as being in "use" level. 1758 */ 1759 break; 1760 } 1761 } 1762 return 0; /* valid */ 1763 } 1764 1765 /* 1766 * Check AH/ESP integrity. 1767 * This function is called from tcp_input(), udp_input(), 1768 * and {ah,esp}4_input for tunnel mode 1769 */ 1770 int 1771 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1772 { 1773 struct secpolicy *sp; 1774 int error; 1775 int result; 1776 1777 KASSERT(m != NULL); 1778 1779 /* get SP for this packet. 1780 * When we are called from ip_forward(), we call 1781 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1782 */ 1783 if (inp == NULL) 1784 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1785 else 1786 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1787 (struct inpcb_hdr *)inp, &error); 1788 1789 if (sp != NULL) { 1790 result = ipsec_in_reject(sp, m); 1791 if (result) 1792 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1793 KEY_SP_UNREF(&sp); 1794 } else { 1795 result = 0; /* XXX should be panic ? 1796 * -> No, there may be error. */ 1797 } 1798 return result; 1799 } 1800 1801 1802 #ifdef INET6 1803 /* 1804 * Check AH/ESP integrity. 1805 * This function is called from tcp6_input(), udp6_input(), 1806 * and {ah,esp}6_input for tunnel mode 1807 */ 1808 int 1809 ipsec6_in_reject(struct mbuf *m, struct in6pcb *in6p) 1810 { 1811 struct secpolicy *sp = NULL; 1812 int error; 1813 int result; 1814 1815 KASSERT(m != NULL); 1816 1817 /* get SP for this packet. 1818 * When we are called from ip_forward(), we call 1819 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1820 */ 1821 if (in6p == NULL) 1822 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1823 else 1824 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1825 (struct inpcb_hdr *)in6p, 1826 &error); 1827 1828 if (sp != NULL) { 1829 result = ipsec_in_reject(sp, m); 1830 if (result) 1831 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1832 KEY_SP_UNREF(&sp); 1833 } else { 1834 result = 0; 1835 } 1836 return result; 1837 } 1838 #endif 1839 1840 /* 1841 * compute the byte size to be occupied by IPsec header. 1842 * in case it is tunneled, it includes the size of outer IP header. 1843 * NOTE: SP passed is free in this function. 1844 */ 1845 static size_t 1846 ipsec_hdrsiz(const struct secpolicy *sp, const struct mbuf *m) 1847 { 1848 struct ipsecrequest *isr; 1849 size_t siz; 1850 1851 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1852 printf("%s: using SP\n", __func__); 1853 kdebug_secpolicy(sp); 1854 } 1855 1856 switch (sp->policy) { 1857 case IPSEC_POLICY_DISCARD: 1858 case IPSEC_POLICY_BYPASS: 1859 case IPSEC_POLICY_NONE: 1860 return 0; 1861 } 1862 1863 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1864 "invalid policy %u", sp->policy); 1865 1866 siz = 0; 1867 for (isr = sp->req; isr != NULL; isr = isr->next) { 1868 size_t clen = 0; 1869 struct secasvar *sav; 1870 1871 switch (isr->saidx.proto) { 1872 case IPPROTO_ESP: 1873 sav = ipsec_lookup_sa(isr, m); 1874 if (sav != NULL) { 1875 clen = esp_hdrsiz(sav); 1876 KEY_SA_UNREF(&sav); 1877 } else 1878 clen = esp_hdrsiz(NULL); 1879 break; 1880 case IPPROTO_AH: 1881 sav = ipsec_lookup_sa(isr, m); 1882 if (sav != NULL) { 1883 clen = ah_hdrsiz(sav); 1884 KEY_SA_UNREF(&sav); 1885 } else 1886 clen = ah_hdrsiz(NULL); 1887 break; 1888 case IPPROTO_IPCOMP: 1889 clen = sizeof(struct ipcomp); 1890 break; 1891 } 1892 1893 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1894 switch (isr->saidx.dst.sa.sa_family) { 1895 case AF_INET: 1896 clen += sizeof(struct ip); 1897 break; 1898 #ifdef INET6 1899 case AF_INET6: 1900 clen += sizeof(struct ip6_hdr); 1901 break; 1902 #endif 1903 default: 1904 IPSECLOG(LOG_ERR, "unknown AF %d in " 1905 "IPsec tunnel SA\n", 1906 ((const struct sockaddr *)&isr->saidx.dst) 1907 ->sa_family); 1908 break; 1909 } 1910 } 1911 siz += clen; 1912 } 1913 1914 return siz; 1915 } 1916 1917 /* This function is called from ip_forward() and ipsec4_hdrsize_tcp(). */ 1918 size_t 1919 ipsec4_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1920 { 1921 struct secpolicy *sp; 1922 int error; 1923 size_t size; 1924 1925 KASSERT(m != NULL); 1926 KASSERTMSG(inp == NULL || inp->inp_socket != NULL, "socket w/o inpcb"); 1927 1928 /* get SP for this packet. 1929 * When we are called from ip_forward(), we call 1930 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1931 */ 1932 if (inp == NULL) 1933 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1934 else 1935 sp = ipsec_getpolicybysock(m, dir, 1936 (struct inpcb_hdr *)inp, &error); 1937 1938 if (sp != NULL) { 1939 size = ipsec_hdrsiz(sp, m); 1940 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%lu.\n", 1941 (unsigned long)size); 1942 1943 KEY_SP_UNREF(&sp); 1944 } else { 1945 size = 0; /* XXX should be panic ? */ 1946 } 1947 return size; 1948 } 1949 1950 #ifdef INET6 1951 /* This function is called from ipsec6_hdrsize_tcp(), 1952 * and maybe from ip6_forward.() 1953 */ 1954 size_t 1955 ipsec6_hdrsiz(struct mbuf *m, u_int dir, struct in6pcb *in6p) 1956 { 1957 struct secpolicy *sp; 1958 int error; 1959 size_t size; 1960 1961 KASSERT(m != NULL); 1962 KASSERTMSG(in6p == NULL || in6p->in6p_socket != NULL, 1963 "socket w/o inpcb"); 1964 1965 /* get SP for this packet */ 1966 /* XXX Is it right to call with IP_FORWARDING. */ 1967 if (in6p == NULL) 1968 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1969 else 1970 sp = ipsec_getpolicybysock(m, dir, 1971 (struct inpcb_hdr *)in6p, 1972 &error); 1973 1974 if (sp == NULL) 1975 return 0; 1976 size = ipsec_hdrsiz(sp, m); 1977 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%zu.\n", size); 1978 KEY_SP_UNREF(&sp); 1979 1980 return size; 1981 } 1982 #endif /*INET6*/ 1983 1984 /* 1985 * Check the variable replay window. 1986 * ipsec_chkreplay() performs replay check before ICV verification. 1987 * ipsec_updatereplay() updates replay bitmap. This must be called after 1988 * ICV verification (it also performs replay check, which is usually done 1989 * beforehand). 1990 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1991 * 1992 * based on RFC 2401. 1993 */ 1994 int 1995 ipsec_chkreplay(u_int32_t seq, const struct secasvar *sav) 1996 { 1997 const struct secreplay *replay; 1998 u_int32_t diff; 1999 int fr; 2000 u_int32_t wsizeb; /* constant: bits of window size */ 2001 int frlast; /* constant: last frame */ 2002 2003 IPSEC_SPLASSERT_SOFTNET(__func__); 2004 2005 KASSERT(sav != NULL); 2006 KASSERT(sav->replay != NULL); 2007 2008 replay = sav->replay; 2009 2010 if (replay->wsize == 0) 2011 return 1; /* no need to check replay. */ 2012 2013 /* constant */ 2014 frlast = replay->wsize - 1; 2015 wsizeb = replay->wsize << 3; 2016 2017 /* sequence number of 0 is invalid */ 2018 if (seq == 0) 2019 return 0; 2020 2021 /* first time is always okay */ 2022 if (replay->count == 0) 2023 return 1; 2024 2025 if (seq > replay->lastseq) { 2026 /* larger sequences are okay */ 2027 return 1; 2028 } else { 2029 /* seq is equal or less than lastseq. */ 2030 diff = replay->lastseq - seq; 2031 2032 /* over range to check, i.e. too old or wrapped */ 2033 if (diff >= wsizeb) 2034 return 0; 2035 2036 fr = frlast - diff / 8; 2037 2038 /* this packet already seen ? */ 2039 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2040 return 0; 2041 2042 /* out of order but good */ 2043 return 1; 2044 } 2045 } 2046 2047 /* 2048 * check replay counter whether to update or not. 2049 * OUT: 0: OK 2050 * 1: NG 2051 */ 2052 int 2053 ipsec_updatereplay(u_int32_t seq, const struct secasvar *sav) 2054 { 2055 struct secreplay *replay; 2056 u_int32_t diff; 2057 int fr; 2058 u_int32_t wsizeb; /* constant: bits of window size */ 2059 int frlast; /* constant: last frame */ 2060 2061 IPSEC_SPLASSERT_SOFTNET(__func__); 2062 2063 KASSERT(sav != NULL); 2064 KASSERT(sav->replay != NULL); 2065 2066 replay = sav->replay; 2067 2068 if (replay->wsize == 0) 2069 goto ok; /* no need to check replay. */ 2070 2071 /* constant */ 2072 frlast = replay->wsize - 1; 2073 wsizeb = replay->wsize << 3; 2074 2075 /* sequence number of 0 is invalid */ 2076 if (seq == 0) 2077 return 1; 2078 2079 /* first time */ 2080 if (replay->count == 0) { 2081 replay->lastseq = seq; 2082 memset(replay->bitmap, 0, replay->wsize); 2083 (replay->bitmap)[frlast] = 1; 2084 goto ok; 2085 } 2086 2087 if (seq > replay->lastseq) { 2088 /* seq is larger than lastseq. */ 2089 diff = seq - replay->lastseq; 2090 2091 /* new larger sequence number */ 2092 if (diff < wsizeb) { 2093 /* In window */ 2094 /* set bit for this packet */ 2095 vshiftl(replay->bitmap, diff, replay->wsize); 2096 (replay->bitmap)[frlast] |= 1; 2097 } else { 2098 /* this packet has a "way larger" */ 2099 memset(replay->bitmap, 0, replay->wsize); 2100 (replay->bitmap)[frlast] = 1; 2101 } 2102 replay->lastseq = seq; 2103 2104 /* larger is good */ 2105 } else { 2106 /* seq is equal or less than lastseq. */ 2107 diff = replay->lastseq - seq; 2108 2109 /* over range to check, i.e. too old or wrapped */ 2110 if (diff >= wsizeb) 2111 return 1; 2112 2113 fr = frlast - diff / 8; 2114 2115 /* this packet already seen ? */ 2116 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2117 return 1; 2118 2119 /* mark as seen */ 2120 (replay->bitmap)[fr] |= (1 << (diff % 8)); 2121 2122 /* out of order but good */ 2123 } 2124 2125 ok: 2126 if (replay->count == ~0) { 2127 char buf[IPSEC_LOGSASTRLEN]; 2128 2129 /* set overflow flag */ 2130 replay->overflow++; 2131 2132 /* don't increment, no more packets accepted */ 2133 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 2134 return 1; 2135 2136 IPSECLOG(LOG_WARNING, "replay counter made %d cycle. %s\n", 2137 replay->overflow, ipsec_logsastr(sav, buf, sizeof(buf))); 2138 } 2139 2140 replay->count++; 2141 2142 return 0; 2143 } 2144 2145 /* 2146 * shift variable length bunffer to left. 2147 * IN: bitmap: pointer to the buffer 2148 * nbit: the number of to shift. 2149 * wsize: buffer size (bytes). 2150 */ 2151 static void 2152 vshiftl(unsigned char *bitmap, int nbit, int wsize) 2153 { 2154 int s, j, i; 2155 unsigned char over; 2156 2157 for (j = 0; j < nbit; j += 8) { 2158 s = (nbit - j < 8) ? (nbit - j): 8; 2159 bitmap[0] <<= s; 2160 for (i = 1; i < wsize; i++) { 2161 over = (bitmap[i] >> (8 - s)); 2162 bitmap[i] <<= s; 2163 bitmap[i-1] |= over; 2164 } 2165 } 2166 2167 return; 2168 } 2169 2170 /* Return a printable string for the address. */ 2171 const char * 2172 ipsec_address(const union sockaddr_union *sa, char *buf, size_t size) 2173 { 2174 switch (sa->sa.sa_family) { 2175 #if INET 2176 case AF_INET: 2177 in_print(buf, size, &sa->sin.sin_addr); 2178 return buf; 2179 #endif /* INET */ 2180 2181 #if INET6 2182 case AF_INET6: 2183 in6_print(buf, size, &sa->sin6.sin6_addr); 2184 return buf; 2185 #endif /* INET6 */ 2186 2187 default: 2188 return "(unknown address family)"; 2189 } 2190 } 2191 2192 const char * 2193 ipsec_logsastr(const struct secasvar *sav, char *buf, size_t size) 2194 { 2195 const struct secasindex *saidx = &sav->sah->saidx; 2196 char sbuf[IPSEC_ADDRSTRLEN], dbuf[IPSEC_ADDRSTRLEN]; 2197 2198 KASSERTMSG(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 2199 "af family mismatch, src %u, dst %u", 2200 saidx->src.sa.sa_family, saidx->dst.sa.sa_family); 2201 2202 snprintf(buf, size, "SA(SPI=%u src=%s dst=%s)", 2203 (u_int32_t)ntohl(sav->spi), 2204 ipsec_address(&saidx->src, sbuf, sizeof(sbuf)), 2205 ipsec_address(&saidx->dst, dbuf, sizeof(dbuf))); 2206 2207 return buf; 2208 } 2209 2210 void 2211 ipsec_dumpmbuf(struct mbuf *m) 2212 { 2213 int totlen; 2214 int i; 2215 u_char *p; 2216 2217 totlen = 0; 2218 printf("---\n"); 2219 while (m) { 2220 p = mtod(m, u_char *); 2221 for (i = 0; i < m->m_len; i++) { 2222 printf("%02x ", p[i]); 2223 totlen++; 2224 if (totlen % 16 == 0) 2225 printf("\n"); 2226 } 2227 m = m->m_next; 2228 } 2229 if (totlen % 16 != 0) 2230 printf("\n"); 2231 printf("---\n"); 2232 } 2233 2234 #ifdef INET6 2235 struct secpolicy * 2236 ipsec6_check_policy(struct mbuf *m, struct in6pcb *in6p, 2237 int flags, int *needipsecp, int *errorp) 2238 { 2239 struct secpolicy *sp = NULL; 2240 int s; 2241 int error = 0; 2242 int needipsec = 0; 2243 2244 if (!ipsec_outdone(m)) { 2245 s = splsoftnet(); 2246 if (in6p != NULL && 2247 ipsec_pcb_skip_ipsec(in6p->in6p_sp, IPSEC_DIR_OUTBOUND)) { 2248 splx(s); 2249 goto skippolicycheck; 2250 } 2251 sp = ipsec6_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error,in6p); 2252 2253 /* 2254 * There are four return cases: 2255 * sp != NULL apply IPsec policy 2256 * sp == NULL, error == 0 no IPsec handling needed 2257 * sp == NULL, error == -EINVAL discard packet w/o error 2258 * sp == NULL, error != 0 discard packet, report error 2259 */ 2260 2261 splx(s); 2262 if (sp == NULL) { 2263 /* 2264 * Caller must check the error return to see if it needs to discard 2265 * the packet. 2266 */ 2267 needipsec = 0; 2268 } else { 2269 needipsec = 1; 2270 } 2271 } 2272 skippolicycheck:; 2273 2274 *errorp = error; 2275 *needipsecp = needipsec; 2276 return sp; 2277 } 2278 2279 int 2280 ipsec6_input(struct mbuf *m) 2281 { 2282 struct secpolicy *sp; 2283 int s, error; 2284 2285 s = splsoftnet(); 2286 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 2287 if (sp != NULL) { 2288 /* 2289 * Check security policy against packet 2290 * attributes. 2291 */ 2292 error = ipsec_in_reject(sp, m); 2293 KEY_SP_UNREF(&sp); 2294 } else { 2295 /* XXX error stat??? */ 2296 error = EINVAL; 2297 IPSECLOG(LOG_DEBUG, "no SP, packet discarded\n");/*XXX*/ 2298 } 2299 splx(s); 2300 2301 return error; 2302 } 2303 #endif /* INET6 */ 2304 2305 2306 2307 /* XXX this stuff doesn't belong here... */ 2308 2309 static struct xformsw *xforms = NULL; 2310 2311 /* 2312 * Register a transform; typically at system startup. 2313 */ 2314 void 2315 xform_register(struct xformsw *xsp) 2316 { 2317 xsp->xf_next = xforms; 2318 xforms = xsp; 2319 } 2320 2321 /* 2322 * Initialize transform support in an sav. 2323 */ 2324 int 2325 xform_init(struct secasvar *sav, int xftype) 2326 { 2327 struct xformsw *xsp; 2328 2329 if (sav->tdb_xform != NULL) /* previously initialized */ 2330 return 0; 2331 for (xsp = xforms; xsp; xsp = xsp->xf_next) 2332 if (xsp->xf_type == xftype) 2333 return (*xsp->xf_init)(sav, xsp); 2334 2335 IPSECLOG(LOG_DEBUG, "no match for xform type %d\n", xftype); 2336 return EINVAL; 2337 } 2338 2339 void 2340 nat_t_ports_get(struct mbuf *m, u_int16_t *dport, u_int16_t *sport) { 2341 struct m_tag *tag; 2342 2343 if ((tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL))) { 2344 *sport = ((u_int16_t *)(tag + 1))[0]; 2345 *dport = ((u_int16_t *)(tag + 1))[1]; 2346 } else 2347 *sport = *dport = 0; 2348 } 2349 2350 /* 2351 * XXXJRT This should be done as a protosw init call. 2352 */ 2353 void 2354 ipsec_attach(void) 2355 { 2356 2357 ipsec_output_init(); 2358 2359 ipsecstat_percpu = percpu_alloc(sizeof(uint64_t) * IPSEC_NSTATS); 2360 2361 sysctl_net_inet_ipsec_setup(NULL); 2362 #ifdef INET6 2363 sysctl_net_inet6_ipsec6_setup(NULL); 2364 #endif 2365 2366 ah_attach(); 2367 esp_attach(); 2368 ipcomp_attach(); 2369 ipe4_attach(); 2370 #ifdef TCP_SIGNATURE 2371 tcpsignature_attach(); 2372 #endif 2373 } 2374
Indexes created Tue Sep 30 10:09:55 GMT 2025