ipsec.c revision 1.123
1 /* $NetBSD: ipsec.c,v 1.123 2017/11/21 07:03:08 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 1.123 2017/11/21 07:03:08 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_dummy_sp __read_mostly = { 143 .state = IPSEC_SPSTATE_ALIVE, 144 /* If ENTRUST, the dummy SP never be used. See ipsec_getpolicybysock. */ 145 .policy = IPSEC_POLICY_ENTRUST, 146 }; 147 148 static struct secpolicy *ipsec_checkpcbcache (struct mbuf *, 149 struct inpcbpolicy *, int); 150 static int ipsec_fillpcbcache (struct inpcbpolicy *, struct mbuf *, 151 struct secpolicy *, int); 152 static int ipsec_invalpcbcache (struct inpcbpolicy *, int); 153 154 /* 155 * Crypto support requirements: 156 * 157 * 1 require hardware support 158 * -1 require software support 159 * 0 take anything 160 */ 161 int crypto_support = 0; 162 163 static struct secpolicy *ipsec_getpolicybysock(struct mbuf *, u_int, 164 struct inpcb_hdr *, int *); 165 166 #ifdef __FreeBSD__ 167 /* net.inet.ipsec */ 168 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_ESP_RANDPAD, 169 esp_randpad, CTLFLAG_RW, &ip4_esp_randpad, 0, ""); 170 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, 171 crypto_support, CTLFLAG_RW, &crypto_support,0, ""); 172 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_replay, CTLFLAG_RW, &ipsec_replay, 0, 173 "Emulate replay attack"); 174 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_integrity, CTLFLAG_RW, 175 &ipsec_integrity, 0, "Emulate man-in-the-middle attack"); 176 #endif /* __FreeBSD__ */ 177 178 #ifdef INET6 179 int ip6_esp_trans_deflev = IPSEC_LEVEL_USE; 180 int ip6_esp_net_deflev = IPSEC_LEVEL_USE; 181 int ip6_ah_trans_deflev = IPSEC_LEVEL_USE; 182 int ip6_ah_net_deflev = IPSEC_LEVEL_USE; 183 struct secpolicy ip6_def_policy; 184 int ip6_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 185 int ip6_esp_randpad = -1; 186 187 188 #ifdef __FreeBSD__ 189 /* net.inet6.ipsec6 */ 190 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_ESP_RANDPAD, 191 esp_randpad, CTLFLAG_RW, &ip6_esp_randpad, 0, ""); 192 #endif /* __FreeBSD__ */ 193 #endif /* INET6 */ 194 195 static int ipsec4_setspidx_inpcb (struct mbuf *, struct inpcb *); 196 #ifdef INET6 197 static int ipsec6_setspidx_in6pcb (struct mbuf *, struct in6pcb *); 198 #endif 199 static int ipsec_setspidx (struct mbuf *, struct secpolicyindex *, int); 200 static void ipsec4_get_ulp (struct mbuf *m, struct secpolicyindex *, int); 201 static int ipsec4_setspidx_ipaddr (struct mbuf *, struct secpolicyindex *); 202 #ifdef INET6 203 static void ipsec6_get_ulp (struct mbuf *m, struct secpolicyindex *, int); 204 static int ipsec6_setspidx_ipaddr (struct mbuf *, struct secpolicyindex *); 205 #endif 206 static void ipsec_delpcbpolicy (struct inpcbpolicy *); 207 #if 0 /* unused */ 208 static struct secpolicy *ipsec_deepcopy_policy (const struct secpolicy *); 209 #endif 210 static int ipsec_set_policy (struct secpolicy **, int, const void *, size_t, 211 kauth_cred_t); 212 static int ipsec_get_policy (struct secpolicy *, struct mbuf **); 213 static void ipsec_destroy_policy(struct secpolicy *); 214 static void vshiftl (unsigned char *, int, int); 215 static size_t ipsec_hdrsiz(const struct secpolicy *, const struct mbuf *); 216 217 /* 218 * Try to validate and use cached policy on a PCB. 219 */ 220 static struct secpolicy * 221 ipsec_checkpcbcache(struct mbuf *m, struct inpcbpolicy *pcbsp, int dir) 222 { 223 struct secpolicyindex spidx; 224 struct secpolicy *sp = NULL; 225 int s; 226 227 KASSERT(IPSEC_DIR_IS_VALID(dir)); 228 KASSERT(pcbsp != NULL); 229 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 230 KASSERT(inph_locked(pcbsp->sp_inph)); 231 232 /* 233 * Checking the generation and sp->state and taking a reference to an SP 234 * must be in a critical section of pserialize. See key_unlink_sp. 235 */ 236 s = pserialize_read_enter(); 237 /* SPD table change invalidate all the caches. */ 238 if (ipsec_spdgen != pcbsp->sp_cache[dir].cachegen) { 239 ipsec_invalpcbcache(pcbsp, dir); 240 goto out; 241 } 242 sp = pcbsp->sp_cache[dir].cachesp; 243 if (sp == NULL) 244 goto out; 245 if (sp->state != IPSEC_SPSTATE_ALIVE) { 246 sp = NULL; 247 ipsec_invalpcbcache(pcbsp, dir); 248 goto out; 249 } 250 if ((pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) == 0) { 251 /* NB: assume ipsec_setspidx never sleep */ 252 if (ipsec_setspidx(m, &spidx, 1) != 0) { 253 sp = NULL; 254 goto out; 255 } 256 257 /* 258 * We have to make an exact match here since the cached rule 259 * might have lower priority than a rule that would otherwise 260 * have matched the packet. 261 */ 262 if (memcmp(&pcbsp->sp_cache[dir].cacheidx, &spidx, 263 sizeof(spidx))) { 264 sp = NULL; 265 goto out; 266 } 267 } else { 268 /* 269 * The pcb is connected, and the L4 code is sure that: 270 * - outgoing side uses inp_[lf]addr 271 * - incoming side looks up policy after inpcb lookup 272 * and address pair is know to be stable. We do not need 273 * to generate spidx again, nor check the address match again. 274 * 275 * For IPv4/v6 SOCK_STREAM sockets, this assumptions holds 276 * and there are calls to ipsec_pcbconn() from in_pcbconnect(). 277 */ 278 } 279 280 sp->lastused = time_second; 281 KEY_SP_REF(sp); 282 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 283 "DP cause refcnt++:%d SP:%p\n", 284 key_sp_refcnt(sp), pcbsp->sp_cache[dir].cachesp); 285 out: 286 pserialize_read_exit(s); 287 return sp; 288 } 289 290 static int 291 ipsec_fillpcbcache(struct inpcbpolicy *pcbsp, struct mbuf *m, 292 struct secpolicy *sp, int dir) 293 { 294 295 KASSERT(IPSEC_DIR_IS_INOROUT(dir)); 296 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 297 KASSERT(inph_locked(pcbsp->sp_inph)); 298 299 pcbsp->sp_cache[dir].cachesp = NULL; 300 pcbsp->sp_cache[dir].cachehint = IPSEC_PCBHINT_UNKNOWN; 301 if (ipsec_setspidx(m, &pcbsp->sp_cache[dir].cacheidx, 1) != 0) { 302 return EINVAL; 303 } 304 pcbsp->sp_cache[dir].cachesp = sp; 305 if (pcbsp->sp_cache[dir].cachesp) { 306 /* 307 * If the PCB is connected, we can remember a hint to 308 * possibly short-circuit IPsec processing in other places. 309 */ 310 if (pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) { 311 switch (pcbsp->sp_cache[dir].cachesp->policy) { 312 case IPSEC_POLICY_NONE: 313 case IPSEC_POLICY_BYPASS: 314 pcbsp->sp_cache[dir].cachehint = 315 IPSEC_PCBHINT_NO; 316 break; 317 default: 318 pcbsp->sp_cache[dir].cachehint = 319 IPSEC_PCBHINT_YES; 320 } 321 } 322 } 323 pcbsp->sp_cache[dir].cachegen = ipsec_spdgen; 324 325 return 0; 326 } 327 328 static int 329 ipsec_invalpcbcache(struct inpcbpolicy *pcbsp, int dir) 330 { 331 int i; 332 333 KASSERT(inph_locked(pcbsp->sp_inph)); 334 335 for (i = IPSEC_DIR_INBOUND; i <= IPSEC_DIR_OUTBOUND; i++) { 336 if (dir != IPSEC_DIR_ANY && i != dir) 337 continue; 338 pcbsp->sp_cache[i].cachesp = NULL; 339 pcbsp->sp_cache[i].cachehint = IPSEC_PCBHINT_UNKNOWN; 340 pcbsp->sp_cache[i].cachegen = 0; 341 memset(&pcbsp->sp_cache[i].cacheidx, 0, 342 sizeof(pcbsp->sp_cache[i].cacheidx)); 343 } 344 return 0; 345 } 346 347 void 348 ipsec_pcbconn(struct inpcbpolicy *pcbsp) 349 { 350 351 KASSERT(inph_locked(pcbsp->sp_inph)); 352 353 pcbsp->sp_cacheflags |= IPSEC_PCBSP_CONNECTED; 354 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 355 } 356 357 void 358 ipsec_pcbdisconn(struct inpcbpolicy *pcbsp) 359 { 360 361 KASSERT(inph_locked(pcbsp->sp_inph)); 362 363 pcbsp->sp_cacheflags &= ~IPSEC_PCBSP_CONNECTED; 364 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 365 } 366 367 void 368 ipsec_invalpcbcacheall(void) 369 { 370 371 if (ipsec_spdgen == UINT_MAX) 372 ipsec_spdgen = 1; 373 else 374 ipsec_spdgen++; 375 } 376 377 /* 378 * Return a held reference to the default SP. 379 */ 380 static struct secpolicy * 381 key_get_default_sp(int af, const char *where, int tag) 382 { 383 struct secpolicy *sp; 384 385 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP from %s:%u\n", where, tag); 386 387 switch(af) { 388 case AF_INET: 389 sp = &ip4_def_policy; 390 break; 391 #ifdef INET6 392 case AF_INET6: 393 sp = &ip6_def_policy; 394 break; 395 #endif 396 default: 397 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 398 "unexpected protocol family %u\n", af); 399 return NULL; 400 } 401 402 if (sp->policy != IPSEC_POLICY_DISCARD && 403 sp->policy != IPSEC_POLICY_NONE) { 404 IPSECLOG(LOG_INFO, "fixed system default policy: %d->%d\n", 405 sp->policy, IPSEC_POLICY_NONE); 406 sp->policy = IPSEC_POLICY_NONE; 407 } 408 KEY_SP_REF(sp); 409 410 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP returns SP:%p (%u)\n", 411 sp, key_sp_refcnt(sp)); 412 return sp; 413 } 414 #define KEY_GET_DEFAULT_SP(af) \ 415 key_get_default_sp((af), __func__, __LINE__) 416 417 /* 418 * For OUTBOUND packet having a socket. Searching SPD for packet, 419 * and return a pointer to SP. 420 * OUT: NULL: no apropreate SP found, the following value is set to error. 421 * 0 : bypass 422 * EACCES : discard packet. 423 * ENOENT : ipsec_acquire() in progress, maybe. 424 * others : error occurred. 425 * others: a pointer to SP 426 * 427 * NOTE: IPv6 mapped address concern is implemented here. 428 */ 429 static struct secpolicy * 430 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb_hdr *inph, 431 int *error) 432 { 433 struct inpcbpolicy *pcbsp = NULL; 434 struct secpolicy *currsp = NULL; /* policy on socket */ 435 struct secpolicy *sp; 436 int af; 437 438 KASSERT(m != NULL); 439 KASSERT(inph != NULL); 440 KASSERT(error != NULL); 441 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 442 443 KASSERT(inph->inph_socket != NULL); 444 KASSERT(inph_locked(inph)); 445 446 /* XXX FIXME inpcb/in6pcb vs socket*/ 447 af = inph->inph_af; 448 KASSERTMSG(af == AF_INET || af == AF_INET6, 449 "unexpected protocol family %u", af); 450 451 KASSERT(inph->inph_sp != NULL); 452 /* If we have a cached entry, and if it is still valid, use it. */ 453 IPSEC_STATINC(IPSEC_STAT_SPDCACHELOOKUP); 454 currsp = ipsec_checkpcbcache(m, inph->inph_sp, dir); 455 if (currsp) { 456 *error = 0; 457 return currsp; 458 } 459 IPSEC_STATINC(IPSEC_STAT_SPDCACHEMISS); 460 461 switch (af) { 462 case AF_INET: { 463 struct inpcb *in4p = (struct inpcb *)inph; 464 /* set spidx in pcb */ 465 *error = ipsec4_setspidx_inpcb(m, in4p); 466 pcbsp = in4p->inp_sp; 467 break; 468 } 469 470 #if defined(INET6) 471 case AF_INET6: { 472 struct in6pcb *in6p = (struct in6pcb *)inph; 473 /* set spidx in pcb */ 474 *error = ipsec6_setspidx_in6pcb(m, in6p); 475 pcbsp = in6p->in6p_sp; 476 break; 477 } 478 #endif 479 default: 480 *error = EPFNOSUPPORT; 481 break; 482 } 483 if (*error) 484 return NULL; 485 486 KASSERT(pcbsp != NULL); 487 switch (dir) { 488 case IPSEC_DIR_INBOUND: 489 currsp = pcbsp->sp_in; 490 break; 491 case IPSEC_DIR_OUTBOUND: 492 currsp = pcbsp->sp_out; 493 break; 494 } 495 KASSERT(currsp != NULL); 496 497 if (pcbsp->priv) { /* when privilieged socket */ 498 switch (currsp->policy) { 499 case IPSEC_POLICY_BYPASS: 500 case IPSEC_POLICY_IPSEC: 501 KEY_SP_REF(currsp); 502 sp = currsp; 503 break; 504 505 case IPSEC_POLICY_ENTRUST: 506 /* look for a policy in SPD */ 507 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 508 if (sp == NULL) /* no SP found */ 509 sp = KEY_GET_DEFAULT_SP(af); 510 break; 511 512 default: 513 IPSECLOG(LOG_ERR, "Invalid policy for PCB %d\n", 514 currsp->policy); 515 *error = EINVAL; 516 return NULL; 517 } 518 } else { /* unpriv, SPD has policy */ 519 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 520 if (sp == NULL) { /* no SP found */ 521 switch (currsp->policy) { 522 case IPSEC_POLICY_BYPASS: 523 IPSECLOG(LOG_ERR, "Illegal policy for " 524 "non-priviliged defined %d\n", 525 currsp->policy); 526 *error = EINVAL; 527 return NULL; 528 529 case IPSEC_POLICY_ENTRUST: 530 sp = KEY_GET_DEFAULT_SP(af); 531 break; 532 533 case IPSEC_POLICY_IPSEC: 534 KEY_SP_REF(currsp); 535 sp = currsp; 536 break; 537 538 default: 539 IPSECLOG(LOG_ERR, "Invalid policy for " 540 "PCB %d\n", currsp->policy); 541 *error = EINVAL; 542 return NULL; 543 } 544 } 545 } 546 KASSERTMSG(sp != NULL, "null SP (priv %u policy %u", pcbsp->priv, 547 currsp->policy); 548 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 549 "DP (priv %u policy %u) allocates SP:%p (refcnt %u)\n", 550 pcbsp->priv, currsp->policy, sp, key_sp_refcnt(sp)); 551 ipsec_fillpcbcache(pcbsp, m, sp, dir); 552 return sp; 553 } 554 555 /* 556 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 557 * and return a pointer to SP. 558 * OUT: positive: a pointer to the entry for security policy leaf matched. 559 * NULL: no apropreate SP found, the following value is set to error. 560 * 0 : bypass 561 * EACCES : discard packet. 562 * ENOENT : ipsec_acquire() in progress, maybe. 563 * others : error occurred. 564 */ 565 struct secpolicy * 566 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 567 { 568 struct secpolicyindex spidx; 569 struct secpolicy *sp; 570 571 KASSERT(m != NULL); 572 KASSERT(error != NULL); 573 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 574 575 sp = NULL; 576 577 /* Make an index to look for a policy. */ 578 *error = ipsec_setspidx(m, &spidx, (flag & IP_FORWARDING) ? 0 : 1); 579 if (*error != 0) { 580 IPSECLOG(LOG_DEBUG, "setpidx failed, dir %u flag %u\n", dir, flag); 581 memset(&spidx, 0, sizeof (spidx)); 582 return NULL; 583 } 584 585 spidx.dir = dir; 586 587 if (key_havesp(dir)) { 588 sp = KEY_LOOKUP_SP_BYSPIDX(&spidx, dir); 589 } 590 591 if (sp == NULL) /* no SP found, use system default */ 592 sp = KEY_GET_DEFAULT_SP(spidx.dst.sa.sa_family); 593 KASSERT(sp != NULL); 594 return sp; 595 } 596 597 struct secpolicy * 598 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 599 struct inpcb *inp) 600 { 601 struct secpolicy *sp; 602 603 *error = 0; 604 605 if (inp == NULL) { 606 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 607 } else { 608 KASSERT(inp->inp_socket != NULL); 609 sp = ipsec_getpolicybysock(m, dir, (struct inpcb_hdr *)inp, error); 610 } 611 if (sp == NULL) { 612 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 613 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 614 return NULL; 615 } 616 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 617 switch (sp->policy) { 618 case IPSEC_POLICY_ENTRUST: 619 default: 620 printf("%s: invalid policy %u\n", __func__, sp->policy); 621 /* fall thru... */ 622 case IPSEC_POLICY_DISCARD: 623 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 624 *error = -EINVAL; /* packet is discarded by caller */ 625 break; 626 case IPSEC_POLICY_BYPASS: 627 case IPSEC_POLICY_NONE: 628 KEY_SP_UNREF(&sp); 629 sp = NULL; /* NB: force NULL result */ 630 break; 631 case IPSEC_POLICY_IPSEC: 632 KASSERT(sp->req != NULL); 633 break; 634 } 635 if (*error != 0) { 636 KEY_SP_UNREF(&sp); 637 sp = NULL; 638 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 639 } 640 return sp; 641 } 642 643 int 644 ipsec4_output(struct mbuf *m, struct inpcb *inp, int flags, 645 u_long *mtu, bool *natt_frag, bool *done) 646 { 647 struct secpolicy *sp = NULL; 648 int error, s; 649 650 /* 651 * Check the security policy (SP) for the packet and, if required, 652 * do IPsec-related processing. There are two cases here; the first 653 * time a packet is sent through it will be untagged and handled by 654 * ipsec4_checkpolicy(). If the packet is resubmitted to ip_output 655 * (e.g. after AH, ESP, etc. processing), there will be a tag to 656 * bypass the lookup and related policy checking. 657 */ 658 if (ipsec_outdone(m)) { 659 return 0; 660 } 661 s = splsoftnet(); 662 if (inp && ipsec_pcb_skip_ipsec(inp->inp_sp, IPSEC_DIR_OUTBOUND)) { 663 splx(s); 664 return 0; 665 } 666 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, inp); 667 668 /* 669 * There are four return cases: 670 * sp != NULL apply IPsec policy 671 * sp == NULL, error == 0 no IPsec handling needed 672 * sp == NULL, error == -EINVAL discard packet w/o error 673 * sp == NULL, error != 0 discard packet, report error 674 */ 675 if (sp == NULL) { 676 splx(s); 677 if (error) { 678 /* 679 * Hack: -EINVAL is used to signal that a packet 680 * should be silently discarded. This is typically 681 * because we asked key management for an SA and 682 * it was delayed (e.g. kicked up to IKE). 683 */ 684 if (error == -EINVAL) 685 error = 0; 686 m_freem(m); 687 *done = true; 688 return error; 689 } 690 /* No IPsec processing for this packet. */ 691 return 0; 692 } 693 694 /* 695 * Do delayed checksums now because we send before 696 * this is done in the normal processing path. 697 */ 698 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 699 in_delayed_cksum(m); 700 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 701 } 702 703 { 704 u_long _mtu = 0; 705 706 /* Note: callee frees mbuf */ 707 error = ipsec4_process_packet(m, sp->req, &_mtu); 708 709 if (error == 0 && _mtu != 0) { 710 /* 711 * NAT-T ESP fragmentation: do not do IPSec processing 712 * now, we will do it on each fragmented packet. 713 */ 714 *mtu = _mtu; 715 *natt_frag = true; 716 KEY_SP_UNREF(&sp); 717 splx(s); 718 return 0; 719 } 720 } 721 /* 722 * Preserve KAME behaviour: ENOENT can be returned 723 * when an SA acquire is in progress. Don't propagate 724 * this to user-level; it confuses applications. 725 * 726 * XXX this will go away when the SADB is redone. 727 */ 728 if (error == ENOENT) 729 error = 0; 730 KEY_SP_UNREF(&sp); 731 splx(s); 732 *done = true; 733 return error; 734 } 735 736 int 737 ipsec4_input(struct mbuf *m, int flags) 738 { 739 struct secpolicy *sp; 740 int error, s; 741 742 s = splsoftnet(); 743 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 744 if (sp == NULL) { 745 splx(s); 746 return EINVAL; 747 } 748 749 /* 750 * Check security policy against packet attributes. 751 */ 752 error = ipsec_in_reject(sp, m); 753 KEY_SP_UNREF(&sp); 754 splx(s); 755 if (error) { 756 return error; 757 } 758 759 if (flags == 0) { 760 /* We are done. */ 761 return 0; 762 } 763 764 /* 765 * Peek at the outbound SP for this packet to determine if 766 * it is a Fast Forward candidate. 767 */ 768 s = splsoftnet(); 769 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, NULL); 770 if (sp != NULL) { 771 m->m_flags &= ~M_CANFASTFWD; 772 KEY_SP_UNREF(&sp); 773 } 774 splx(s); 775 return 0; 776 } 777 778 int 779 ipsec4_forward(struct mbuf *m, int *destmtu) 780 { 781 /* 782 * If the packet is routed over IPsec tunnel, tell the 783 * originator the tunnel MTU. 784 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 785 * XXX quickhack!!! 786 */ 787 struct secpolicy *sp; 788 size_t ipsechdr; 789 int error; 790 791 sp = ipsec4_getpolicybyaddr(m, 792 IPSEC_DIR_OUTBOUND, IP_FORWARDING, &error); 793 if (sp == NULL) { 794 return EINVAL; 795 } 796 797 /* Count IPsec header size. */ 798 ipsechdr = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, NULL); 799 800 /* 801 * Find the correct route for outer IPv4 header, compute tunnel MTU. 802 */ 803 if (sp->req) { 804 struct secasvar *sav; 805 806 sav = ipsec_lookup_sa(sp->req, m); 807 if (sav != NULL) { 808 struct route *ro; 809 struct rtentry *rt; 810 811 ro = &sav->sah->sa_route; 812 rt = rtcache_validate(ro); 813 if (rt && rt->rt_ifp) { 814 *destmtu = rt->rt_rmx.rmx_mtu ? 815 rt->rt_rmx.rmx_mtu : rt->rt_ifp->if_mtu; 816 *destmtu -= ipsechdr; 817 } 818 rtcache_unref(rt, ro); 819 KEY_SA_UNREF(&sav); 820 } 821 } 822 KEY_SP_UNREF(&sp); 823 return 0; 824 } 825 826 #ifdef INET6 827 struct secpolicy * 828 ipsec6_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 829 struct in6pcb *in6p) 830 { 831 struct secpolicy *sp; 832 833 *error = 0; 834 835 if (in6p == NULL) { 836 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 837 } else { 838 KASSERT(in6p->in6p_socket != NULL); 839 sp = ipsec_getpolicybysock(m, dir, (struct inpcb_hdr *)in6p, error); 840 } 841 if (sp == NULL) { 842 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 843 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 844 return NULL; 845 } 846 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 847 switch (sp->policy) { 848 case IPSEC_POLICY_ENTRUST: 849 default: 850 printf("%s: invalid policy %u\n", __func__, sp->policy); 851 /* fall thru... */ 852 case IPSEC_POLICY_DISCARD: 853 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 854 *error = -EINVAL; /* packet is discarded by caller */ 855 break; 856 case IPSEC_POLICY_BYPASS: 857 case IPSEC_POLICY_NONE: 858 KEY_SP_UNREF(&sp); 859 sp = NULL; /* NB: force NULL result */ 860 break; 861 case IPSEC_POLICY_IPSEC: 862 KASSERT(sp->req != NULL); 863 break; 864 } 865 if (*error != 0) { 866 KEY_SP_UNREF(&sp); 867 sp = NULL; 868 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 869 } 870 return sp; 871 } 872 #endif /* INET6 */ 873 874 static int 875 ipsec4_setspidx_inpcb(struct mbuf *m, struct inpcb *pcb) 876 { 877 int error; 878 879 KASSERT(pcb != NULL); 880 KASSERT(pcb->inp_sp != NULL); 881 KASSERT(pcb->inp_sp->sp_out != NULL); 882 KASSERT(pcb->inp_sp->sp_in != NULL); 883 884 error = ipsec_setspidx(m, &pcb->inp_sp->sp_in->spidx, 1); 885 if (error == 0) { 886 pcb->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 887 pcb->inp_sp->sp_out->spidx = pcb->inp_sp->sp_in->spidx; 888 pcb->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 889 } else { 890 memset(&pcb->inp_sp->sp_in->spidx, 0, 891 sizeof(pcb->inp_sp->sp_in->spidx)); 892 memset(&pcb->inp_sp->sp_out->spidx, 0, 893 sizeof(pcb->inp_sp->sp_in->spidx)); 894 } 895 return error; 896 } 897 898 #ifdef INET6 899 static int 900 ipsec6_setspidx_in6pcb(struct mbuf *m, struct in6pcb *pcb) 901 { 902 struct secpolicyindex *spidx; 903 int error; 904 905 KASSERT(pcb != NULL); 906 KASSERT(pcb->in6p_sp != NULL); 907 KASSERT(pcb->in6p_sp->sp_out != NULL); 908 KASSERT(pcb->in6p_sp->sp_in != NULL); 909 910 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 911 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 912 913 spidx = &pcb->in6p_sp->sp_in->spidx; 914 error = ipsec_setspidx(m, spidx, 1); 915 if (error) 916 goto bad; 917 spidx->dir = IPSEC_DIR_INBOUND; 918 919 spidx = &pcb->in6p_sp->sp_out->spidx; 920 error = ipsec_setspidx(m, spidx, 1); 921 if (error) 922 goto bad; 923 spidx->dir = IPSEC_DIR_OUTBOUND; 924 925 return 0; 926 927 bad: 928 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 929 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 930 return error; 931 } 932 #endif 933 934 /* 935 * configure security policy index (src/dst/proto/sport/dport) 936 * by looking at the content of mbuf. 937 * the caller is responsible for error recovery (like clearing up spidx). 938 */ 939 static int 940 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 941 { 942 struct ip *ip = NULL; 943 struct ip ipbuf; 944 u_int v; 945 struct mbuf *n; 946 int len; 947 int error; 948 949 KASSERT(m != NULL); 950 951 /* 952 * validate m->m_pkthdr.len. we see incorrect length if we 953 * mistakenly call this function with inconsistent mbuf chain 954 * (like 4.4BSD tcp/udp processing). XXX should we panic here? 955 */ 956 len = 0; 957 for (n = m; n; n = n->m_next) 958 len += n->m_len; 959 if (m->m_pkthdr.len != len) { 960 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 961 "total of m_len(%d) != pkthdr.len(%d), ignored.\n", 962 len, m->m_pkthdr.len); 963 return EINVAL; 964 } 965 966 if (m->m_pkthdr.len < sizeof(struct ip)) { 967 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 968 "pkthdr.len(%d) < sizeof(struct ip), ignored.\n", 969 m->m_pkthdr.len); 970 return EINVAL; 971 } 972 973 if (m->m_len >= sizeof(*ip)) 974 ip = mtod(m, struct ip *); 975 else { 976 m_copydata(m, 0, sizeof(ipbuf), &ipbuf); 977 ip = &ipbuf; 978 } 979 v = ip->ip_v; 980 switch (v) { 981 case 4: 982 error = ipsec4_setspidx_ipaddr(m, spidx); 983 if (error) 984 return error; 985 ipsec4_get_ulp(m, spidx, needport); 986 return 0; 987 #ifdef INET6 988 case 6: 989 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 990 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 991 "pkthdr.len(%d) < sizeof(struct ip6_hdr), " 992 "ignored.\n", m->m_pkthdr.len); 993 return EINVAL; 994 } 995 error = ipsec6_setspidx_ipaddr(m, spidx); 996 if (error) 997 return error; 998 ipsec6_get_ulp(m, spidx, needport); 999 return 0; 1000 #endif 1001 default: 1002 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1003 "unknown IP version %u, ignored.\n", v); 1004 return EINVAL; 1005 } 1006 } 1007 1008 static void 1009 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 1010 { 1011 u_int8_t nxt; 1012 int off; 1013 1014 /* sanity check */ 1015 KASSERT(m != NULL); 1016 KASSERTMSG(m->m_pkthdr.len >= sizeof(struct ip), "packet too short"); 1017 1018 /* NB: ip_input() flips it into host endian XXX need more checking */ 1019 if (m->m_len >= sizeof(struct ip)) { 1020 struct ip *ip = mtod(m, struct ip *); 1021 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 1022 goto done; 1023 off = ip->ip_hl << 2; 1024 nxt = ip->ip_p; 1025 } else { 1026 struct ip ih; 1027 1028 m_copydata(m, 0, sizeof (struct ip), &ih); 1029 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 1030 goto done; 1031 off = ih.ip_hl << 2; 1032 nxt = ih.ip_p; 1033 } 1034 1035 while (off < m->m_pkthdr.len) { 1036 struct ip6_ext ip6e; 1037 struct tcphdr th; 1038 struct udphdr uh; 1039 struct icmp icmph; 1040 1041 switch (nxt) { 1042 case IPPROTO_TCP: 1043 spidx->ul_proto = nxt; 1044 if (!needport) 1045 goto done_proto; 1046 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1047 goto done; 1048 m_copydata(m, off, sizeof (th), &th); 1049 spidx->src.sin.sin_port = th.th_sport; 1050 spidx->dst.sin.sin_port = th.th_dport; 1051 return; 1052 case IPPROTO_UDP: 1053 spidx->ul_proto = nxt; 1054 if (!needport) 1055 goto done_proto; 1056 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1057 goto done; 1058 m_copydata(m, off, sizeof (uh), &uh); 1059 spidx->src.sin.sin_port = uh.uh_sport; 1060 spidx->dst.sin.sin_port = uh.uh_dport; 1061 return; 1062 case IPPROTO_AH: 1063 if (m->m_pkthdr.len > off + sizeof(ip6e)) 1064 goto done; 1065 /* XXX sigh, this works but is totally bogus */ 1066 m_copydata(m, off, sizeof(ip6e), &ip6e); 1067 off += (ip6e.ip6e_len + 2) << 2; 1068 nxt = ip6e.ip6e_nxt; 1069 break; 1070 case IPPROTO_ICMP: 1071 spidx->ul_proto = nxt; 1072 if (off + sizeof(struct icmp) > m->m_pkthdr.len) 1073 return; 1074 m_copydata(m, off, sizeof(icmph), &icmph); 1075 ((struct sockaddr_in *)&spidx->src)->sin_port = 1076 htons((uint16_t)icmph.icmp_type); 1077 ((struct sockaddr_in *)&spidx->dst)->sin_port = 1078 htons((uint16_t)icmph.icmp_code); 1079 return; 1080 default: 1081 /* XXX intermediate headers??? */ 1082 spidx->ul_proto = nxt; 1083 goto done_proto; 1084 } 1085 } 1086 done: 1087 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1088 done_proto: 1089 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 1090 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 1091 } 1092 1093 /* assumes that m is sane */ 1094 static int 1095 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1096 { 1097 static const struct sockaddr_in template = { 1098 sizeof (struct sockaddr_in), 1099 AF_INET, 1100 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 1101 }; 1102 1103 spidx->src.sin = template; 1104 spidx->dst.sin = template; 1105 1106 if (m->m_len < sizeof (struct ip)) { 1107 m_copydata(m, offsetof(struct ip, ip_src), 1108 sizeof(struct in_addr), &spidx->src.sin.sin_addr); 1109 m_copydata(m, offsetof(struct ip, ip_dst), 1110 sizeof(struct in_addr), &spidx->dst.sin.sin_addr); 1111 } else { 1112 struct ip *ip = mtod(m, struct ip *); 1113 spidx->src.sin.sin_addr = ip->ip_src; 1114 spidx->dst.sin.sin_addr = ip->ip_dst; 1115 } 1116 1117 spidx->prefs = sizeof(struct in_addr) << 3; 1118 spidx->prefd = sizeof(struct in_addr) << 3; 1119 1120 return 0; 1121 } 1122 1123 #ifdef INET6 1124 static void 1125 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, 1126 int needport) 1127 { 1128 int off, nxt; 1129 struct tcphdr th; 1130 struct udphdr uh; 1131 struct icmp6_hdr icmph; 1132 1133 KASSERT(m != NULL); 1134 1135 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1136 kdebug_mbuf(__func__, m); 1137 } 1138 1139 /* set default */ 1140 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1141 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 1142 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 1143 1144 nxt = -1; 1145 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 1146 if (off < 0 || m->m_pkthdr.len < off) 1147 return; 1148 1149 switch (nxt) { 1150 case IPPROTO_TCP: 1151 spidx->ul_proto = nxt; 1152 if (!needport) 1153 break; 1154 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1155 break; 1156 m_copydata(m, off, sizeof(th), &th); 1157 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 1158 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 1159 break; 1160 case IPPROTO_UDP: 1161 spidx->ul_proto = nxt; 1162 if (!needport) 1163 break; 1164 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1165 break; 1166 m_copydata(m, off, sizeof(uh), &uh); 1167 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 1168 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 1169 break; 1170 case IPPROTO_ICMPV6: 1171 spidx->ul_proto = nxt; 1172 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 1173 break; 1174 m_copydata(m, off, sizeof(icmph), &icmph); 1175 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 1176 htons((uint16_t)icmph.icmp6_type); 1177 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 1178 htons((uint16_t)icmph.icmp6_code); 1179 break; 1180 default: 1181 /* XXX intermediate headers??? */ 1182 spidx->ul_proto = nxt; 1183 break; 1184 } 1185 } 1186 1187 /* assumes that m is sane */ 1188 static int 1189 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1190 { 1191 struct ip6_hdr *ip6 = NULL; 1192 struct ip6_hdr ip6buf; 1193 struct sockaddr_in6 *sin6; 1194 1195 if (m->m_len >= sizeof(*ip6)) 1196 ip6 = mtod(m, struct ip6_hdr *); 1197 else { 1198 m_copydata(m, 0, sizeof(ip6buf), &ip6buf); 1199 ip6 = &ip6buf; 1200 } 1201 1202 sin6 = (struct sockaddr_in6 *)&spidx->src; 1203 memset(sin6, 0, sizeof(*sin6)); 1204 sin6->sin6_family = AF_INET6; 1205 sin6->sin6_len = sizeof(struct sockaddr_in6); 1206 memcpy(&sin6->sin6_addr, &ip6->ip6_src, sizeof(ip6->ip6_src)); 1207 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 1208 sin6->sin6_addr.s6_addr16[1] = 0; 1209 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 1210 } 1211 spidx->prefs = sizeof(struct in6_addr) << 3; 1212 1213 sin6 = (struct sockaddr_in6 *)&spidx->dst; 1214 memset(sin6, 0, sizeof(*sin6)); 1215 sin6->sin6_family = AF_INET6; 1216 sin6->sin6_len = sizeof(struct sockaddr_in6); 1217 memcpy(&sin6->sin6_addr, &ip6->ip6_dst, sizeof(ip6->ip6_dst)); 1218 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 1219 sin6->sin6_addr.s6_addr16[1] = 0; 1220 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 1221 } 1222 spidx->prefd = sizeof(struct in6_addr) << 3; 1223 1224 return 0; 1225 } 1226 #endif 1227 1228 static void 1229 ipsec_delpcbpolicy(struct inpcbpolicy *p) 1230 { 1231 1232 kmem_intr_free(p, sizeof(*p)); 1233 } 1234 1235 /* initialize policy in PCB */ 1236 int 1237 ipsec_init_policy(struct socket *so, struct inpcbpolicy **policy) 1238 { 1239 struct inpcbpolicy *new; 1240 1241 KASSERT(so != NULL); 1242 KASSERT(policy != NULL); 1243 1244 new = kmem_intr_zalloc(sizeof(*new), KM_NOSLEEP); 1245 if (new == NULL) { 1246 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1247 return ENOBUFS; 1248 } 1249 1250 if (IPSEC_PRIVILEGED_SO(so)) 1251 new->priv = 1; 1252 else 1253 new->priv = 0; 1254 1255 /* 1256 * Set dummy SPs. Actual SPs will be allocated later if needed. 1257 */ 1258 new->sp_in = &ipsec_dummy_sp; 1259 new->sp_out = &ipsec_dummy_sp; 1260 1261 *policy = new; 1262 1263 return 0; 1264 } 1265 1266 #if 0 /* unused */ 1267 /* copy old ipsec policy into new */ 1268 int 1269 ipsec_copy_policy(const struct inpcbpolicy *old, struct inpcbpolicy *new) 1270 { 1271 struct secpolicy *sp; 1272 1273 sp = ipsec_deepcopy_policy(old->sp_in); 1274 if (sp) { 1275 KEY_SP_UNREF(&new->sp_in); 1276 new->sp_in = sp; 1277 } else 1278 return ENOBUFS; 1279 1280 sp = ipsec_deepcopy_policy(old->sp_out); 1281 if (sp) { 1282 KEY_SP_UNREF(&new->sp_out); 1283 new->sp_out = sp; 1284 } else 1285 return ENOBUFS; 1286 1287 new->priv = old->priv; 1288 1289 return 0; 1290 } 1291 1292 /* deep-copy a policy in PCB */ 1293 static struct secpolicy * 1294 ipsec_deepcopy_policy(const struct secpolicy *src) 1295 { 1296 struct ipsecrequest *newchain = NULL; 1297 const struct ipsecrequest *p; 1298 struct ipsecrequest **q; 1299 struct secpolicy *dst; 1300 1301 if (src == NULL) 1302 return NULL; 1303 dst = KEY_NEWSP(); 1304 if (dst == NULL) 1305 return NULL; 1306 1307 /* 1308 * deep-copy IPsec request chain. This is required since struct 1309 * ipsecrequest is not reference counted. 1310 */ 1311 q = &newchain; 1312 for (p = src->req; p; p = p->next) { 1313 *q = kmem_zalloc(sizeof(**q), KM_SLEEP); 1314 (*q)->next = NULL; 1315 1316 (*q)->saidx.proto = p->saidx.proto; 1317 (*q)->saidx.mode = p->saidx.mode; 1318 (*q)->level = p->level; 1319 (*q)->saidx.reqid = p->saidx.reqid; 1320 1321 memcpy(&(*q)->saidx.src, &p->saidx.src, sizeof((*q)->saidx.src)); 1322 memcpy(&(*q)->saidx.dst, &p->saidx.dst, sizeof((*q)->saidx.dst)); 1323 1324 (*q)->sp = dst; 1325 1326 q = &((*q)->next); 1327 } 1328 1329 dst->req = newchain; 1330 dst->state = src->state; 1331 dst->policy = src->policy; 1332 /* do not touch the refcnt fields */ 1333 1334 return dst; 1335 } 1336 #endif 1337 1338 static void 1339 ipsec_destroy_policy(struct secpolicy *sp) 1340 { 1341 1342 if (sp == &ipsec_dummy_sp) 1343 ; /* It's dummy. No need to free it. */ 1344 else { 1345 /* 1346 * We cannot destroy here because it can be called in 1347 * softint. So mark the SP as DEAD and let the timer 1348 * destroy it. See key_timehandler_spd. 1349 */ 1350 sp->state = IPSEC_SPSTATE_DEAD; 1351 } 1352 } 1353 1354 /* set policy and ipsec request if present. */ 1355 static int 1356 ipsec_set_policy( 1357 struct secpolicy **policy, 1358 int optname, 1359 const void *request, 1360 size_t len, 1361 kauth_cred_t cred 1362 ) 1363 { 1364 const struct sadb_x_policy *xpl; 1365 struct secpolicy *newsp = NULL, *oldsp; 1366 int error; 1367 1368 KASSERT(!cpu_softintr_p()); 1369 1370 /* sanity check. */ 1371 if (policy == NULL || *policy == NULL || request == NULL) 1372 return EINVAL; 1373 if (len < sizeof(*xpl)) 1374 return EINVAL; 1375 xpl = (const struct sadb_x_policy *)request; 1376 1377 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1378 kdebug_sadb_xpolicy("set passed policy", request); 1379 } 1380 1381 /* check policy type */ 1382 /* ipsec_set_policy() accepts IPSEC, ENTRUST and BYPASS. */ 1383 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 1384 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1385 return EINVAL; 1386 1387 /* check privileged socket */ 1388 if (xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1389 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPSEC, 1390 KAUTH_REQ_NETWORK_IPSEC_BYPASS, NULL, NULL, NULL); 1391 if (error) 1392 return (error); 1393 } 1394 1395 /* allocation new SP entry */ 1396 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1397 return error; 1398 1399 key_init_sp(newsp); 1400 newsp->created = time_uptime; 1401 /* Insert the global list for SPs for sockets */ 1402 key_socksplist_add(newsp); 1403 1404 /* clear old SP and set new SP */ 1405 oldsp = *policy; 1406 *policy = newsp; 1407 ipsec_destroy_policy(oldsp); 1408 1409 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1410 printf("%s: new policy\n", __func__); 1411 kdebug_secpolicy(newsp); 1412 } 1413 1414 return 0; 1415 } 1416 1417 static int 1418 ipsec_get_policy(struct secpolicy *policy, struct mbuf **mp) 1419 { 1420 1421 /* sanity check. */ 1422 if (policy == NULL || mp == NULL) 1423 return EINVAL; 1424 1425 *mp = key_sp2msg(policy, M_NOWAIT); 1426 if (!*mp) { 1427 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1428 return ENOBUFS; 1429 } 1430 1431 (*mp)->m_type = MT_DATA; 1432 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1433 kdebug_mbuf(__func__, *mp); 1434 } 1435 1436 return 0; 1437 } 1438 1439 int 1440 ipsec4_set_policy(struct inpcb *inp, int optname, const void *request, 1441 size_t len, kauth_cred_t cred) 1442 { 1443 const struct sadb_x_policy *xpl; 1444 struct secpolicy **policy; 1445 1446 KASSERT(!cpu_softintr_p()); 1447 KASSERT(inp_locked(inp)); 1448 1449 /* sanity check. */ 1450 if (inp == NULL || request == NULL) 1451 return EINVAL; 1452 if (len < sizeof(*xpl)) 1453 return EINVAL; 1454 xpl = (const struct sadb_x_policy *)request; 1455 1456 KASSERT(inp->inp_sp != NULL); 1457 1458 /* select direction */ 1459 switch (xpl->sadb_x_policy_dir) { 1460 case IPSEC_DIR_INBOUND: 1461 policy = &inp->inp_sp->sp_in; 1462 break; 1463 case IPSEC_DIR_OUTBOUND: 1464 policy = &inp->inp_sp->sp_out; 1465 break; 1466 default: 1467 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1468 xpl->sadb_x_policy_dir); 1469 return EINVAL; 1470 } 1471 1472 return ipsec_set_policy(policy, optname, request, len, cred); 1473 } 1474 1475 int 1476 ipsec4_get_policy(struct inpcb *inp, const void *request, size_t len, 1477 struct mbuf **mp) 1478 { 1479 const struct sadb_x_policy *xpl; 1480 struct secpolicy *policy; 1481 1482 /* sanity check. */ 1483 if (inp == NULL || request == NULL || mp == NULL) 1484 return EINVAL; 1485 KASSERT(inp->inp_sp != NULL); 1486 if (len < sizeof(*xpl)) 1487 return EINVAL; 1488 xpl = (const struct sadb_x_policy *)request; 1489 1490 /* select direction */ 1491 switch (xpl->sadb_x_policy_dir) { 1492 case IPSEC_DIR_INBOUND: 1493 policy = inp->inp_sp->sp_in; 1494 break; 1495 case IPSEC_DIR_OUTBOUND: 1496 policy = inp->inp_sp->sp_out; 1497 break; 1498 default: 1499 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1500 xpl->sadb_x_policy_dir); 1501 return EINVAL; 1502 } 1503 1504 return ipsec_get_policy(policy, mp); 1505 } 1506 1507 /* delete policy in PCB */ 1508 int 1509 ipsec4_delete_pcbpolicy(struct inpcb *inp) 1510 { 1511 1512 KASSERT(inp != NULL); 1513 1514 if (inp->inp_sp == NULL) 1515 return 0; 1516 1517 if (inp->inp_sp->sp_in != NULL) 1518 ipsec_destroy_policy(inp->inp_sp->sp_in); 1519 1520 if (inp->inp_sp->sp_out != NULL) 1521 ipsec_destroy_policy(inp->inp_sp->sp_out); 1522 1523 ipsec_invalpcbcache(inp->inp_sp, IPSEC_DIR_ANY); 1524 1525 ipsec_delpcbpolicy(inp->inp_sp); 1526 inp->inp_sp = NULL; 1527 1528 return 0; 1529 } 1530 1531 #ifdef INET6 1532 int 1533 ipsec6_set_policy(struct in6pcb *in6p, int optname, const void *request, 1534 size_t len, kauth_cred_t cred) 1535 { 1536 const struct sadb_x_policy *xpl; 1537 struct secpolicy **policy; 1538 1539 KASSERT(!cpu_softintr_p()); 1540 KASSERT(in6p_locked(in6p)); 1541 1542 /* sanity check. */ 1543 if (in6p == NULL || request == NULL) 1544 return EINVAL; 1545 if (len < sizeof(*xpl)) 1546 return EINVAL; 1547 xpl = (const struct sadb_x_policy *)request; 1548 1549 /* select direction */ 1550 switch (xpl->sadb_x_policy_dir) { 1551 case IPSEC_DIR_INBOUND: 1552 policy = &in6p->in6p_sp->sp_in; 1553 break; 1554 case IPSEC_DIR_OUTBOUND: 1555 policy = &in6p->in6p_sp->sp_out; 1556 break; 1557 default: 1558 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1559 xpl->sadb_x_policy_dir); 1560 return EINVAL; 1561 } 1562 1563 return ipsec_set_policy(policy, optname, request, len, cred); 1564 } 1565 1566 int 1567 ipsec6_get_policy(struct in6pcb *in6p, const void *request, size_t len, 1568 struct mbuf **mp) 1569 { 1570 const struct sadb_x_policy *xpl; 1571 struct secpolicy *policy; 1572 1573 /* sanity check. */ 1574 if (in6p == NULL || request == NULL || mp == NULL) 1575 return EINVAL; 1576 KASSERT(in6p->in6p_sp != NULL); 1577 if (len < sizeof(*xpl)) 1578 return EINVAL; 1579 xpl = (const struct sadb_x_policy *)request; 1580 1581 /* select direction */ 1582 switch (xpl->sadb_x_policy_dir) { 1583 case IPSEC_DIR_INBOUND: 1584 policy = in6p->in6p_sp->sp_in; 1585 break; 1586 case IPSEC_DIR_OUTBOUND: 1587 policy = in6p->in6p_sp->sp_out; 1588 break; 1589 default: 1590 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1591 xpl->sadb_x_policy_dir); 1592 return EINVAL; 1593 } 1594 1595 return ipsec_get_policy(policy, mp); 1596 } 1597 1598 int 1599 ipsec6_delete_pcbpolicy(struct in6pcb *in6p) 1600 { 1601 1602 KASSERT(in6p != NULL); 1603 1604 if (in6p->in6p_sp == NULL) 1605 return 0; 1606 1607 if (in6p->in6p_sp->sp_in != NULL) 1608 ipsec_destroy_policy(in6p->in6p_sp->sp_in); 1609 1610 if (in6p->in6p_sp->sp_out != NULL) 1611 ipsec_destroy_policy(in6p->in6p_sp->sp_out); 1612 1613 ipsec_invalpcbcache(in6p->in6p_sp, IPSEC_DIR_ANY); 1614 1615 ipsec_delpcbpolicy(in6p->in6p_sp); 1616 in6p->in6p_sp = NULL; 1617 1618 return 0; 1619 } 1620 #endif 1621 1622 /* 1623 * return current level. 1624 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1625 */ 1626 u_int 1627 ipsec_get_reqlevel(const struct ipsecrequest *isr) 1628 { 1629 u_int level = 0; 1630 u_int esp_trans_deflev, esp_net_deflev; 1631 u_int ah_trans_deflev, ah_net_deflev; 1632 1633 KASSERT(isr != NULL); 1634 KASSERT(isr->sp != NULL); 1635 KASSERTMSG( 1636 isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1637 "af family mismatch, src %u, dst %u", 1638 isr->sp->spidx.src.sa.sa_family, isr->sp->spidx.dst.sa.sa_family); 1639 1640 /* XXX note that we have ipseclog() expanded here - code sync issue */ 1641 #define IPSEC_CHECK_DEFAULT(lev) \ 1642 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1643 && (lev) != IPSEC_LEVEL_UNIQUE) ? \ 1644 (ipsec_debug ? log(LOG_INFO, "fixed system default level " #lev \ 1645 ":%d->%d\n", (lev), IPSEC_LEVEL_REQUIRE) : (void)0), \ 1646 (lev) = IPSEC_LEVEL_REQUIRE, (lev) \ 1647 : (lev)) 1648 1649 /* set default level */ 1650 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1651 #ifdef INET 1652 case AF_INET: 1653 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_trans_deflev); 1654 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_net_deflev); 1655 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_trans_deflev); 1656 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_net_deflev); 1657 break; 1658 #endif 1659 #ifdef INET6 1660 case AF_INET6: 1661 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_trans_deflev); 1662 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_net_deflev); 1663 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_trans_deflev); 1664 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_net_deflev); 1665 break; 1666 #endif /* INET6 */ 1667 default: 1668 panic("%s: unknown af %u", __func__, 1669 isr->sp->spidx.src.sa.sa_family); 1670 } 1671 1672 #undef IPSEC_CHECK_DEFAULT 1673 1674 /* set level */ 1675 switch (isr->level) { 1676 case IPSEC_LEVEL_DEFAULT: 1677 switch (isr->saidx.proto) { 1678 case IPPROTO_ESP: 1679 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1680 level = esp_net_deflev; 1681 else 1682 level = esp_trans_deflev; 1683 break; 1684 case IPPROTO_AH: 1685 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1686 level = ah_net_deflev; 1687 else 1688 level = ah_trans_deflev; 1689 break; 1690 case IPPROTO_IPCOMP: 1691 /* 1692 * we don't really care, as IPcomp document says that 1693 * we shouldn't compress small packets 1694 */ 1695 level = IPSEC_LEVEL_USE; 1696 break; 1697 default: 1698 panic("%s: Illegal protocol defined %u", __func__, 1699 isr->saidx.proto); 1700 } 1701 break; 1702 1703 case IPSEC_LEVEL_USE: 1704 case IPSEC_LEVEL_REQUIRE: 1705 level = isr->level; 1706 break; 1707 case IPSEC_LEVEL_UNIQUE: 1708 level = IPSEC_LEVEL_REQUIRE; 1709 break; 1710 1711 default: 1712 panic("%s: Illegal IPsec level %u", __func__, isr->level); 1713 } 1714 1715 return level; 1716 } 1717 1718 /* 1719 * Check security policy requirements against the actual 1720 * packet contents. Return one if the packet should be 1721 * reject as "invalid"; otherwiser return zero to have the 1722 * packet treated as "valid". 1723 * 1724 * OUT: 1725 * 0: valid 1726 * 1: invalid 1727 */ 1728 int 1729 ipsec_in_reject(const struct secpolicy *sp, const struct mbuf *m) 1730 { 1731 struct ipsecrequest *isr; 1732 1733 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1734 printf("%s: using SP\n", __func__); 1735 kdebug_secpolicy(sp); 1736 } 1737 1738 /* check policy */ 1739 switch (sp->policy) { 1740 case IPSEC_POLICY_DISCARD: 1741 return 1; 1742 case IPSEC_POLICY_BYPASS: 1743 case IPSEC_POLICY_NONE: 1744 return 0; 1745 } 1746 1747 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1748 "invalid policy %u", sp->policy); 1749 1750 /* XXX should compare policy against ipsec header history */ 1751 1752 for (isr = sp->req; isr != NULL; isr = isr->next) { 1753 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1754 continue; 1755 switch (isr->saidx.proto) { 1756 case IPPROTO_ESP: 1757 if ((m->m_flags & M_DECRYPTED) == 0) { 1758 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1759 "ESP m_flags:%x\n", m->m_flags); 1760 return 1; 1761 } 1762 break; 1763 case IPPROTO_AH: 1764 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1765 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1766 "AH m_flags:%x\n", m->m_flags); 1767 return 1; 1768 } 1769 break; 1770 case IPPROTO_IPCOMP: 1771 /* 1772 * we don't really care, as IPcomp document 1773 * says that we shouldn't compress small 1774 * packets, IPComp policy should always be 1775 * treated as being in "use" level. 1776 */ 1777 break; 1778 } 1779 } 1780 return 0; /* valid */ 1781 } 1782 1783 /* 1784 * Check AH/ESP integrity. 1785 * This function is called from tcp_input(), udp_input(), 1786 * and {ah,esp}4_input for tunnel mode 1787 */ 1788 int 1789 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1790 { 1791 struct secpolicy *sp; 1792 int error; 1793 int result; 1794 1795 KASSERT(m != NULL); 1796 1797 /* get SP for this packet. 1798 * When we are called from ip_forward(), we call 1799 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1800 */ 1801 if (inp == NULL) 1802 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1803 else 1804 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1805 (struct inpcb_hdr *)inp, &error); 1806 1807 if (sp != NULL) { 1808 result = ipsec_in_reject(sp, m); 1809 if (result) 1810 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1811 KEY_SP_UNREF(&sp); 1812 } else { 1813 result = 0; /* XXX should be panic ? 1814 * -> No, there may be error. */ 1815 } 1816 return result; 1817 } 1818 1819 1820 #ifdef INET6 1821 /* 1822 * Check AH/ESP integrity. 1823 * This function is called from tcp6_input(), udp6_input(), 1824 * and {ah,esp}6_input for tunnel mode 1825 */ 1826 int 1827 ipsec6_in_reject(struct mbuf *m, struct in6pcb *in6p) 1828 { 1829 struct secpolicy *sp = NULL; 1830 int error; 1831 int result; 1832 1833 KASSERT(m != NULL); 1834 1835 /* get SP for this packet. 1836 * When we are called from ip_forward(), we call 1837 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1838 */ 1839 if (in6p == NULL) 1840 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1841 else 1842 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1843 (struct inpcb_hdr *)in6p, 1844 &error); 1845 1846 if (sp != NULL) { 1847 result = ipsec_in_reject(sp, m); 1848 if (result) 1849 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1850 KEY_SP_UNREF(&sp); 1851 } else { 1852 result = 0; 1853 } 1854 return result; 1855 } 1856 #endif 1857 1858 /* 1859 * compute the byte size to be occupied by IPsec header. 1860 * in case it is tunneled, it includes the size of outer IP header. 1861 * NOTE: SP passed is free in this function. 1862 */ 1863 static size_t 1864 ipsec_hdrsiz(const struct secpolicy *sp, const struct mbuf *m) 1865 { 1866 struct ipsecrequest *isr; 1867 size_t siz; 1868 1869 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1870 printf("%s: using SP\n", __func__); 1871 kdebug_secpolicy(sp); 1872 } 1873 1874 switch (sp->policy) { 1875 case IPSEC_POLICY_DISCARD: 1876 case IPSEC_POLICY_BYPASS: 1877 case IPSEC_POLICY_NONE: 1878 return 0; 1879 } 1880 1881 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1882 "invalid policy %u", sp->policy); 1883 1884 siz = 0; 1885 for (isr = sp->req; isr != NULL; isr = isr->next) { 1886 size_t clen = 0; 1887 struct secasvar *sav; 1888 1889 switch (isr->saidx.proto) { 1890 case IPPROTO_ESP: 1891 sav = ipsec_lookup_sa(isr, m); 1892 if (sav != NULL) { 1893 clen = esp_hdrsiz(sav); 1894 KEY_SA_UNREF(&sav); 1895 } else 1896 clen = esp_hdrsiz(NULL); 1897 break; 1898 case IPPROTO_AH: 1899 sav = ipsec_lookup_sa(isr, m); 1900 if (sav != NULL) { 1901 clen = ah_hdrsiz(sav); 1902 KEY_SA_UNREF(&sav); 1903 } else 1904 clen = ah_hdrsiz(NULL); 1905 break; 1906 case IPPROTO_IPCOMP: 1907 clen = sizeof(struct ipcomp); 1908 break; 1909 } 1910 1911 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1912 switch (isr->saidx.dst.sa.sa_family) { 1913 case AF_INET: 1914 clen += sizeof(struct ip); 1915 break; 1916 #ifdef INET6 1917 case AF_INET6: 1918 clen += sizeof(struct ip6_hdr); 1919 break; 1920 #endif 1921 default: 1922 IPSECLOG(LOG_ERR, "unknown AF %d in " 1923 "IPsec tunnel SA\n", 1924 ((const struct sockaddr *)&isr->saidx.dst) 1925 ->sa_family); 1926 break; 1927 } 1928 } 1929 siz += clen; 1930 } 1931 1932 return siz; 1933 } 1934 1935 /* This function is called from ip_forward() and ipsec4_hdrsize_tcp(). */ 1936 size_t 1937 ipsec4_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1938 { 1939 struct secpolicy *sp; 1940 int error; 1941 size_t size; 1942 1943 KASSERT(m != NULL); 1944 KASSERTMSG(inp == NULL || inp->inp_socket != NULL, "socket w/o inpcb"); 1945 1946 /* get SP for this packet. 1947 * When we are called from ip_forward(), we call 1948 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1949 */ 1950 if (inp == NULL) 1951 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1952 else 1953 sp = ipsec_getpolicybysock(m, dir, 1954 (struct inpcb_hdr *)inp, &error); 1955 1956 if (sp != NULL) { 1957 size = ipsec_hdrsiz(sp, m); 1958 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%lu.\n", 1959 (unsigned long)size); 1960 1961 KEY_SP_UNREF(&sp); 1962 } else { 1963 size = 0; /* XXX should be panic ? */ 1964 } 1965 return size; 1966 } 1967 1968 #ifdef INET6 1969 /* This function is called from ipsec6_hdrsize_tcp(), 1970 * and maybe from ip6_forward.() 1971 */ 1972 size_t 1973 ipsec6_hdrsiz(struct mbuf *m, u_int dir, struct in6pcb *in6p) 1974 { 1975 struct secpolicy *sp; 1976 int error; 1977 size_t size; 1978 1979 KASSERT(m != NULL); 1980 KASSERTMSG(in6p == NULL || in6p->in6p_socket != NULL, 1981 "socket w/o inpcb"); 1982 1983 /* get SP for this packet */ 1984 /* XXX Is it right to call with IP_FORWARDING. */ 1985 if (in6p == NULL) 1986 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1987 else 1988 sp = ipsec_getpolicybysock(m, dir, 1989 (struct inpcb_hdr *)in6p, 1990 &error); 1991 1992 if (sp == NULL) 1993 return 0; 1994 size = ipsec_hdrsiz(sp, m); 1995 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%zu.\n", size); 1996 KEY_SP_UNREF(&sp); 1997 1998 return size; 1999 } 2000 #endif /*INET6*/ 2001 2002 /* 2003 * Check the variable replay window. 2004 * ipsec_chkreplay() performs replay check before ICV verification. 2005 * ipsec_updatereplay() updates replay bitmap. This must be called after 2006 * ICV verification (it also performs replay check, which is usually done 2007 * beforehand). 2008 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 2009 * 2010 * based on RFC 2401. 2011 */ 2012 int 2013 ipsec_chkreplay(u_int32_t seq, const struct secasvar *sav) 2014 { 2015 const struct secreplay *replay; 2016 u_int32_t diff; 2017 int fr; 2018 u_int32_t wsizeb; /* constant: bits of window size */ 2019 int frlast; /* constant: last frame */ 2020 2021 IPSEC_SPLASSERT_SOFTNET(__func__); 2022 2023 KASSERT(sav != NULL); 2024 KASSERT(sav->replay != NULL); 2025 2026 replay = sav->replay; 2027 2028 if (replay->wsize == 0) 2029 return 1; /* no need to check replay. */ 2030 2031 /* constant */ 2032 frlast = replay->wsize - 1; 2033 wsizeb = replay->wsize << 3; 2034 2035 /* sequence number of 0 is invalid */ 2036 if (seq == 0) 2037 return 0; 2038 2039 /* first time is always okay */ 2040 if (replay->count == 0) 2041 return 1; 2042 2043 if (seq > replay->lastseq) { 2044 /* larger sequences are okay */ 2045 return 1; 2046 } else { 2047 /* seq is equal or less than lastseq. */ 2048 diff = replay->lastseq - seq; 2049 2050 /* over range to check, i.e. too old or wrapped */ 2051 if (diff >= wsizeb) 2052 return 0; 2053 2054 fr = frlast - diff / 8; 2055 2056 /* this packet already seen ? */ 2057 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2058 return 0; 2059 2060 /* out of order but good */ 2061 return 1; 2062 } 2063 } 2064 2065 /* 2066 * check replay counter whether to update or not. 2067 * OUT: 0: OK 2068 * 1: NG 2069 */ 2070 int 2071 ipsec_updatereplay(u_int32_t seq, const struct secasvar *sav) 2072 { 2073 struct secreplay *replay; 2074 u_int32_t diff; 2075 int fr; 2076 u_int32_t wsizeb; /* constant: bits of window size */ 2077 int frlast; /* constant: last frame */ 2078 2079 IPSEC_SPLASSERT_SOFTNET(__func__); 2080 2081 KASSERT(sav != NULL); 2082 KASSERT(sav->replay != NULL); 2083 2084 replay = sav->replay; 2085 2086 if (replay->wsize == 0) 2087 goto ok; /* no need to check replay. */ 2088 2089 /* constant */ 2090 frlast = replay->wsize - 1; 2091 wsizeb = replay->wsize << 3; 2092 2093 /* sequence number of 0 is invalid */ 2094 if (seq == 0) 2095 return 1; 2096 2097 /* first time */ 2098 if (replay->count == 0) { 2099 replay->lastseq = seq; 2100 memset(replay->bitmap, 0, replay->wsize); 2101 (replay->bitmap)[frlast] = 1; 2102 goto ok; 2103 } 2104 2105 if (seq > replay->lastseq) { 2106 /* seq is larger than lastseq. */ 2107 diff = seq - replay->lastseq; 2108 2109 /* new larger sequence number */ 2110 if (diff < wsizeb) { 2111 /* In window */ 2112 /* set bit for this packet */ 2113 vshiftl(replay->bitmap, diff, replay->wsize); 2114 (replay->bitmap)[frlast] |= 1; 2115 } else { 2116 /* this packet has a "way larger" */ 2117 memset(replay->bitmap, 0, replay->wsize); 2118 (replay->bitmap)[frlast] = 1; 2119 } 2120 replay->lastseq = seq; 2121 2122 /* larger is good */ 2123 } else { 2124 /* seq is equal or less than lastseq. */ 2125 diff = replay->lastseq - seq; 2126 2127 /* over range to check, i.e. too old or wrapped */ 2128 if (diff >= wsizeb) 2129 return 1; 2130 2131 fr = frlast - diff / 8; 2132 2133 /* this packet already seen ? */ 2134 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2135 return 1; 2136 2137 /* mark as seen */ 2138 (replay->bitmap)[fr] |= (1 << (diff % 8)); 2139 2140 /* out of order but good */ 2141 } 2142 2143 ok: 2144 if (replay->count == ~0) { 2145 char buf[IPSEC_LOGSASTRLEN]; 2146 2147 /* set overflow flag */ 2148 replay->overflow++; 2149 2150 /* don't increment, no more packets accepted */ 2151 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 2152 return 1; 2153 2154 IPSECLOG(LOG_WARNING, "replay counter made %d cycle. %s\n", 2155 replay->overflow, ipsec_logsastr(sav, buf, sizeof(buf))); 2156 } 2157 2158 replay->count++; 2159 2160 return 0; 2161 } 2162 2163 /* 2164 * shift variable length bunffer to left. 2165 * IN: bitmap: pointer to the buffer 2166 * nbit: the number of to shift. 2167 * wsize: buffer size (bytes). 2168 */ 2169 static void 2170 vshiftl(unsigned char *bitmap, int nbit, int wsize) 2171 { 2172 int s, j, i; 2173 unsigned char over; 2174 2175 for (j = 0; j < nbit; j += 8) { 2176 s = (nbit - j < 8) ? (nbit - j): 8; 2177 bitmap[0] <<= s; 2178 for (i = 1; i < wsize; i++) { 2179 over = (bitmap[i] >> (8 - s)); 2180 bitmap[i] <<= s; 2181 bitmap[i-1] |= over; 2182 } 2183 } 2184 2185 return; 2186 } 2187 2188 /* Return a printable string for the address. */ 2189 const char * 2190 ipsec_address(const union sockaddr_union *sa, char *buf, size_t size) 2191 { 2192 switch (sa->sa.sa_family) { 2193 #if INET 2194 case AF_INET: 2195 in_print(buf, size, &sa->sin.sin_addr); 2196 return buf; 2197 #endif /* INET */ 2198 2199 #if INET6 2200 case AF_INET6: 2201 in6_print(buf, size, &sa->sin6.sin6_addr); 2202 return buf; 2203 #endif /* INET6 */ 2204 2205 default: 2206 return "(unknown address family)"; 2207 } 2208 } 2209 2210 const char * 2211 ipsec_logsastr(const struct secasvar *sav, char *buf, size_t size) 2212 { 2213 const struct secasindex *saidx = &sav->sah->saidx; 2214 char sbuf[IPSEC_ADDRSTRLEN], dbuf[IPSEC_ADDRSTRLEN]; 2215 2216 KASSERTMSG(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 2217 "af family mismatch, src %u, dst %u", 2218 saidx->src.sa.sa_family, saidx->dst.sa.sa_family); 2219 2220 snprintf(buf, size, "SA(SPI=%u src=%s dst=%s)", 2221 (u_int32_t)ntohl(sav->spi), 2222 ipsec_address(&saidx->src, sbuf, sizeof(sbuf)), 2223 ipsec_address(&saidx->dst, dbuf, sizeof(dbuf))); 2224 2225 return buf; 2226 } 2227 2228 void 2229 ipsec_dumpmbuf(struct mbuf *m) 2230 { 2231 int totlen; 2232 int i; 2233 u_char *p; 2234 2235 totlen = 0; 2236 printf("---\n"); 2237 while (m) { 2238 p = mtod(m, u_char *); 2239 for (i = 0; i < m->m_len; i++) { 2240 printf("%02x ", p[i]); 2241 totlen++; 2242 if (totlen % 16 == 0) 2243 printf("\n"); 2244 } 2245 m = m->m_next; 2246 } 2247 if (totlen % 16 != 0) 2248 printf("\n"); 2249 printf("---\n"); 2250 } 2251 2252 #ifdef INET6 2253 struct secpolicy * 2254 ipsec6_check_policy(struct mbuf *m, struct in6pcb *in6p, 2255 int flags, int *needipsecp, int *errorp) 2256 { 2257 struct secpolicy *sp = NULL; 2258 int s; 2259 int error = 0; 2260 int needipsec = 0; 2261 2262 if (!ipsec_outdone(m)) { 2263 s = splsoftnet(); 2264 if (in6p != NULL && 2265 ipsec_pcb_skip_ipsec(in6p->in6p_sp, IPSEC_DIR_OUTBOUND)) { 2266 splx(s); 2267 goto skippolicycheck; 2268 } 2269 sp = ipsec6_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error,in6p); 2270 2271 /* 2272 * There are four return cases: 2273 * sp != NULL apply IPsec policy 2274 * sp == NULL, error == 0 no IPsec handling needed 2275 * sp == NULL, error == -EINVAL discard packet w/o error 2276 * sp == NULL, error != 0 discard packet, report error 2277 */ 2278 2279 splx(s); 2280 if (sp == NULL) { 2281 /* 2282 * Caller must check the error return to see if it needs to discard 2283 * the packet. 2284 */ 2285 needipsec = 0; 2286 } else { 2287 needipsec = 1; 2288 } 2289 } 2290 skippolicycheck:; 2291 2292 *errorp = error; 2293 *needipsecp = needipsec; 2294 return sp; 2295 } 2296 2297 int 2298 ipsec6_input(struct mbuf *m) 2299 { 2300 struct secpolicy *sp; 2301 int s, error; 2302 2303 s = splsoftnet(); 2304 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 2305 if (sp != NULL) { 2306 /* 2307 * Check security policy against packet 2308 * attributes. 2309 */ 2310 error = ipsec_in_reject(sp, m); 2311 KEY_SP_UNREF(&sp); 2312 } else { 2313 /* XXX error stat??? */ 2314 error = EINVAL; 2315 IPSECLOG(LOG_DEBUG, "no SP, packet discarded\n");/*XXX*/ 2316 } 2317 splx(s); 2318 2319 return error; 2320 } 2321 #endif /* INET6 */ 2322 2323 2324 2325 /* XXX this stuff doesn't belong here... */ 2326 2327 static struct xformsw *xforms = NULL; 2328 2329 /* 2330 * Register a transform; typically at system startup. 2331 */ 2332 void 2333 xform_register(struct xformsw *xsp) 2334 { 2335 xsp->xf_next = xforms; 2336 xforms = xsp; 2337 } 2338 2339 /* 2340 * Initialize transform support in an sav. 2341 */ 2342 int 2343 xform_init(struct secasvar *sav, int xftype) 2344 { 2345 struct xformsw *xsp; 2346 2347 if (sav->tdb_xform != NULL) /* previously initialized */ 2348 return 0; 2349 for (xsp = xforms; xsp; xsp = xsp->xf_next) 2350 if (xsp->xf_type == xftype) 2351 return (*xsp->xf_init)(sav, xsp); 2352 2353 IPSECLOG(LOG_DEBUG, "no match for xform type %d\n", xftype); 2354 return EINVAL; 2355 } 2356 2357 void 2358 nat_t_ports_get(struct mbuf *m, u_int16_t *dport, u_int16_t *sport) { 2359 struct m_tag *tag; 2360 2361 if ((tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL))) { 2362 *sport = ((u_int16_t *)(tag + 1))[0]; 2363 *dport = ((u_int16_t *)(tag + 1))[1]; 2364 } else 2365 *sport = *dport = 0; 2366 } 2367 2368 /* 2369 * XXXJRT This should be done as a protosw init call. 2370 */ 2371 void 2372 ipsec_attach(void) 2373 { 2374 2375 ipsec_output_init(); 2376 2377 ipsecstat_percpu = percpu_alloc(sizeof(uint64_t) * IPSEC_NSTATS); 2378 2379 sysctl_net_inet_ipsec_setup(NULL); 2380 #ifdef INET6 2381 sysctl_net_inet6_ipsec6_setup(NULL); 2382 #endif 2383 2384 ah_attach(); 2385 esp_attach(); 2386 ipcomp_attach(); 2387 ipe4_attach(); 2388 #ifdef TCP_SIGNATURE 2389 tcpsignature_attach(); 2390 #endif 2391 } 2392
Indexes created Mon Sep 22 10:09:38 GMT 2025