ipsec.c revision 1.114
1 /* $NetBSD: ipsec.c,v 1.114 2017/08/02 03:45:57 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 1.114 2017/08/02 03:45:57 ozaki-r Exp $"); 36 37 /* 38 * IPsec controller part. 39 */ 40 41 #if defined(_KERNEL_OPT) 42 #include "opt_inet.h" 43 #include "opt_ipsec.h" 44 #endif 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/mbuf.h> 49 #include <sys/domain.h> 50 #include <sys/protosw.h> 51 #include <sys/socket.h> 52 #include <sys/socketvar.h> 53 #include <sys/errno.h> 54 #include <sys/time.h> 55 #include <sys/kernel.h> 56 #include <sys/syslog.h> 57 #include <sys/sysctl.h> 58 #include <sys/proc.h> 59 #include <sys/kauth.h> 60 #include <sys/cpu.h> 61 #include <sys/kmem.h> 62 #include <sys/pserialize.h> 63 64 #include <net/if.h> 65 #include <net/route.h> 66 67 #include <netinet/in.h> 68 #include <netinet/in_systm.h> 69 #include <netinet/ip.h> 70 #include <netinet/ip_var.h> 71 #include <netinet/in_var.h> 72 #include <netinet/udp.h> 73 #include <netinet/udp_var.h> 74 #include <netinet/tcp.h> 75 #include <netinet/udp.h> 76 #include <netinet/ip_icmp.h> 77 #include <netinet/ip_private.h> 78 79 #include <netinet/ip6.h> 80 #ifdef INET6 81 #include <netinet6/ip6_var.h> 82 #endif 83 #include <netinet/in_pcb.h> 84 #ifdef INET6 85 #include <netinet6/in6_pcb.h> 86 #include <netinet/icmp6.h> 87 #endif 88 89 #include <netipsec/ipsec.h> 90 #include <netipsec/ipsec_var.h> 91 #include <netipsec/ipsec_private.h> 92 #ifdef INET6 93 #include <netipsec/ipsec6.h> 94 #endif 95 #include <netipsec/ah_var.h> 96 #include <netipsec/esp_var.h> 97 #include <netipsec/ipcomp.h> /*XXX*/ 98 #include <netipsec/ipcomp_var.h> 99 100 #include <netipsec/key.h> 101 #include <netipsec/keydb.h> 102 #include <netipsec/key_debug.h> 103 104 #include <netipsec/xform.h> 105 106 #include <net/net_osdep.h> 107 108 int ipsec_used = 0; 109 int ipsec_enabled = 1; 110 111 #ifdef IPSEC_DEBUG 112 int ipsec_debug = 1; 113 114 /* 115 * When set to 1, IPsec will send packets with the same sequence number. 116 * This allows to verify if the other side has proper replay attacks detection. 117 */ 118 int ipsec_replay = 0; 119 120 /* 121 * When set 1, IPsec will send packets with corrupted HMAC. 122 * This allows to verify if the other side properly detects modified packets. 123 */ 124 int ipsec_integrity = 0; 125 #else 126 int ipsec_debug = 0; 127 #endif 128 129 percpu_t *ipsecstat_percpu; 130 int ip4_ah_offsetmask = 0; /* maybe IP_DF? */ 131 int ip4_ipsec_dfbit = 2; /* DF bit on encap. 0: clear 1: set 2: copy */ 132 int ip4_esp_trans_deflev = IPSEC_LEVEL_USE; 133 int ip4_esp_net_deflev = IPSEC_LEVEL_USE; 134 int ip4_ah_trans_deflev = IPSEC_LEVEL_USE; 135 int ip4_ah_net_deflev = IPSEC_LEVEL_USE; 136 struct secpolicy ip4_def_policy; 137 int ip4_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 138 int ip4_esp_randpad = -1; 139 140 u_int ipsec_spdgen = 1; /* SPD generation # */ 141 142 static struct secpolicy *ipsec_checkpcbcache (struct mbuf *, 143 struct inpcbpolicy *, int); 144 static int ipsec_fillpcbcache (struct inpcbpolicy *, struct mbuf *, 145 struct secpolicy *, int); 146 static int ipsec_invalpcbcache (struct inpcbpolicy *, int); 147 148 /* 149 * Crypto support requirements: 150 * 151 * 1 require hardware support 152 * -1 require software support 153 * 0 take anything 154 */ 155 int crypto_support = 0; 156 157 static struct secpolicy *ipsec_getpolicybysock(struct mbuf *, u_int, 158 struct inpcb_hdr *, int *); 159 160 #ifdef __FreeBSD__ 161 /* net.inet.ipsec */ 162 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_ESP_RANDPAD, 163 esp_randpad, CTLFLAG_RW, &ip4_esp_randpad, 0, ""); 164 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, 165 crypto_support, CTLFLAG_RW, &crypto_support,0, ""); 166 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_replay, CTLFLAG_RW, &ipsec_replay, 0, 167 "Emulate replay attack"); 168 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_integrity, CTLFLAG_RW, 169 &ipsec_integrity, 0, "Emulate man-in-the-middle attack"); 170 #endif /* __FreeBSD__ */ 171 172 #ifdef INET6 173 int ip6_esp_trans_deflev = IPSEC_LEVEL_USE; 174 int ip6_esp_net_deflev = IPSEC_LEVEL_USE; 175 int ip6_ah_trans_deflev = IPSEC_LEVEL_USE; 176 int ip6_ah_net_deflev = IPSEC_LEVEL_USE; 177 struct secpolicy ip6_def_policy; 178 int ip6_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 179 int ip6_esp_randpad = -1; 180 181 182 #ifdef __FreeBSD__ 183 /* net.inet6.ipsec6 */ 184 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_ESP_RANDPAD, 185 esp_randpad, CTLFLAG_RW, &ip6_esp_randpad, 0, ""); 186 #endif /* __FreeBSD__ */ 187 #endif /* INET6 */ 188 189 static int ipsec4_setspidx_inpcb (struct mbuf *, struct inpcb *); 190 #ifdef INET6 191 static int ipsec6_setspidx_in6pcb (struct mbuf *, struct in6pcb *); 192 #endif 193 static int ipsec_setspidx (struct mbuf *, struct secpolicyindex *, int); 194 static void ipsec4_get_ulp (struct mbuf *m, struct secpolicyindex *, int); 195 static int ipsec4_setspidx_ipaddr (struct mbuf *, struct secpolicyindex *); 196 #ifdef INET6 197 static void ipsec6_get_ulp (struct mbuf *m, struct secpolicyindex *, int); 198 static int ipsec6_setspidx_ipaddr (struct mbuf *, struct secpolicyindex *); 199 #endif 200 static void ipsec_delpcbpolicy (struct inpcbpolicy *); 201 static struct secpolicy *ipsec_deepcopy_policy (const struct secpolicy *); 202 static int ipsec_set_policy (struct secpolicy **, int, const void *, size_t, 203 kauth_cred_t); 204 static int ipsec_get_policy (struct secpolicy *, struct mbuf **); 205 static void ipsec_destroy_policy(struct secpolicy *); 206 static void vshiftl (unsigned char *, int, int); 207 static size_t ipsec_hdrsiz (const struct secpolicy *); 208 209 /* 210 * Try to validate and use cached policy on a PCB. 211 */ 212 static struct secpolicy * 213 ipsec_checkpcbcache(struct mbuf *m, struct inpcbpolicy *pcbsp, int dir) 214 { 215 struct secpolicyindex spidx; 216 struct secpolicy *sp = NULL; 217 int s; 218 219 KASSERT(IPSEC_DIR_IS_VALID(dir)); 220 KASSERT(pcbsp != NULL); 221 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 222 KASSERT(inph_locked(pcbsp->sp_inph)); 223 224 /* 225 * Checking the generation and sp->state and taking a reference to an SP 226 * must be in a critical section of pserialize. See key_unlink_sp. 227 */ 228 s = pserialize_read_enter(); 229 /* SPD table change invalidate all the caches. */ 230 if (ipsec_spdgen != pcbsp->sp_cache[dir].cachegen) { 231 ipsec_invalpcbcache(pcbsp, dir); 232 goto out; 233 } 234 sp = pcbsp->sp_cache[dir].cachesp; 235 if (sp == NULL) 236 goto out; 237 if (sp->state != IPSEC_SPSTATE_ALIVE) { 238 sp = NULL; 239 ipsec_invalpcbcache(pcbsp, dir); 240 goto out; 241 } 242 if ((pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) == 0) { 243 /* NB: assume ipsec_setspidx never sleep */ 244 if (ipsec_setspidx(m, &spidx, 1) != 0) { 245 sp = NULL; 246 goto out; 247 } 248 249 /* 250 * We have to make an exact match here since the cached rule 251 * might have lower priority than a rule that would otherwise 252 * have matched the packet. 253 */ 254 if (memcmp(&pcbsp->sp_cache[dir].cacheidx, &spidx, 255 sizeof(spidx))) { 256 sp = NULL; 257 goto out; 258 } 259 } else { 260 /* 261 * The pcb is connected, and the L4 code is sure that: 262 * - outgoing side uses inp_[lf]addr 263 * - incoming side looks up policy after inpcb lookup 264 * and address pair is know to be stable. We do not need 265 * to generate spidx again, nor check the address match again. 266 * 267 * For IPv4/v6 SOCK_STREAM sockets, this assumptions holds 268 * and there are calls to ipsec_pcbconn() from in_pcbconnect(). 269 */ 270 } 271 272 sp->lastused = time_second; 273 KEY_SP_REF(sp); 274 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 275 "DP cause refcnt++:%d SP:%p\n", 276 key_sp_refcnt(sp), pcbsp->sp_cache[dir].cachesp); 277 out: 278 pserialize_read_exit(s); 279 return sp; 280 } 281 282 static int 283 ipsec_fillpcbcache(struct inpcbpolicy *pcbsp, struct mbuf *m, 284 struct secpolicy *sp, int dir) 285 { 286 287 KASSERT(IPSEC_DIR_IS_INOROUT(dir)); 288 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 289 KASSERT(inph_locked(pcbsp->sp_inph)); 290 291 pcbsp->sp_cache[dir].cachesp = NULL; 292 pcbsp->sp_cache[dir].cachehint = IPSEC_PCBHINT_UNKNOWN; 293 if (ipsec_setspidx(m, &pcbsp->sp_cache[dir].cacheidx, 1) != 0) { 294 return EINVAL; 295 } 296 pcbsp->sp_cache[dir].cachesp = sp; 297 if (pcbsp->sp_cache[dir].cachesp) { 298 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 299 "DP cause refcnt++:%d SP:%p\n", 300 key_sp_refcnt(pcbsp->sp_cache[dir].cachesp), 301 pcbsp->sp_cache[dir].cachesp); 302 303 /* 304 * If the PCB is connected, we can remember a hint to 305 * possibly short-circuit IPsec processing in other places. 306 */ 307 if (pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) { 308 switch (pcbsp->sp_cache[dir].cachesp->policy) { 309 case IPSEC_POLICY_NONE: 310 case IPSEC_POLICY_BYPASS: 311 pcbsp->sp_cache[dir].cachehint = 312 IPSEC_PCBHINT_NO; 313 break; 314 default: 315 pcbsp->sp_cache[dir].cachehint = 316 IPSEC_PCBHINT_YES; 317 } 318 } 319 } 320 pcbsp->sp_cache[dir].cachegen = ipsec_spdgen; 321 322 return 0; 323 } 324 325 static int 326 ipsec_invalpcbcache(struct inpcbpolicy *pcbsp, int dir) 327 { 328 int i; 329 330 KASSERT(inph_locked(pcbsp->sp_inph)); 331 332 for (i = IPSEC_DIR_INBOUND; i <= IPSEC_DIR_OUTBOUND; i++) { 333 if (dir != IPSEC_DIR_ANY && i != dir) 334 continue; 335 pcbsp->sp_cache[i].cachesp = NULL; 336 pcbsp->sp_cache[i].cachehint = IPSEC_PCBHINT_UNKNOWN; 337 pcbsp->sp_cache[i].cachegen = 0; 338 memset(&pcbsp->sp_cache[i].cacheidx, 0, 339 sizeof(pcbsp->sp_cache[i].cacheidx)); 340 } 341 return 0; 342 } 343 344 void 345 ipsec_pcbconn(struct inpcbpolicy *pcbsp) 346 { 347 348 KASSERT(inph_locked(pcbsp->sp_inph)); 349 350 pcbsp->sp_cacheflags |= IPSEC_PCBSP_CONNECTED; 351 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 352 } 353 354 void 355 ipsec_pcbdisconn(struct inpcbpolicy *pcbsp) 356 { 357 358 KASSERT(inph_locked(pcbsp->sp_inph)); 359 360 pcbsp->sp_cacheflags &= ~IPSEC_PCBSP_CONNECTED; 361 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 362 } 363 364 void 365 ipsec_invalpcbcacheall(void) 366 { 367 368 if (ipsec_spdgen == UINT_MAX) 369 ipsec_spdgen = 1; 370 else 371 ipsec_spdgen++; 372 } 373 374 /* 375 * Return a held reference to the default SP. 376 */ 377 static struct secpolicy * 378 key_get_default_sp(int af, const char *where, int tag) 379 { 380 struct secpolicy *sp; 381 382 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP from %s:%u\n", where, tag); 383 384 switch(af) { 385 case AF_INET: 386 sp = &ip4_def_policy; 387 break; 388 #ifdef INET6 389 case AF_INET6: 390 sp = &ip6_def_policy; 391 break; 392 #endif 393 default: 394 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 395 "unexpected protocol family %u\n", af); 396 return NULL; 397 } 398 399 if (sp->policy != IPSEC_POLICY_DISCARD && 400 sp->policy != IPSEC_POLICY_NONE) { 401 IPSECLOG(LOG_INFO, "fixed system default policy: %d->%d\n", 402 sp->policy, IPSEC_POLICY_NONE); 403 sp->policy = IPSEC_POLICY_NONE; 404 } 405 KEY_SP_REF(sp); 406 407 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP returns SP:%p (%u)\n", 408 sp, key_sp_refcnt(sp)); 409 return sp; 410 } 411 #define KEY_GET_DEFAULT_SP(af) \ 412 key_get_default_sp((af), __func__, __LINE__) 413 414 /* 415 * For OUTBOUND packet having a socket. Searching SPD for packet, 416 * and return a pointer to SP. 417 * OUT: NULL: no apropreate SP found, the following value is set to error. 418 * 0 : bypass 419 * EACCES : discard packet. 420 * ENOENT : ipsec_acquire() in progress, maybe. 421 * others : error occurred. 422 * others: a pointer to SP 423 * 424 * NOTE: IPv6 mapped address concern is implemented here. 425 */ 426 static struct secpolicy * 427 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb_hdr *inph, 428 int *error) 429 { 430 struct inpcbpolicy *pcbsp = NULL; 431 struct secpolicy *currsp = NULL; /* policy on socket */ 432 struct secpolicy *sp; 433 int af; 434 435 KASSERT(m != NULL); 436 KASSERT(inph != NULL); 437 KASSERT(error != NULL); 438 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 439 440 KASSERT(inph->inph_socket != NULL); 441 KASSERT(inph_locked(inph)); 442 443 /* XXX FIXME inpcb/in6pcb vs socket*/ 444 af = inph->inph_af; 445 KASSERTMSG(af == AF_INET || af == AF_INET6, 446 "unexpected protocol family %u", af); 447 448 KASSERT(inph->inph_sp != NULL); 449 /* If we have a cached entry, and if it is still valid, use it. */ 450 IPSEC_STATINC(IPSEC_STAT_SPDCACHELOOKUP); 451 currsp = ipsec_checkpcbcache(m, inph->inph_sp, dir); 452 if (currsp) { 453 *error = 0; 454 return currsp; 455 } 456 IPSEC_STATINC(IPSEC_STAT_SPDCACHEMISS); 457 458 switch (af) { 459 case AF_INET: { 460 struct inpcb *in4p = (struct inpcb *)inph; 461 /* set spidx in pcb */ 462 *error = ipsec4_setspidx_inpcb(m, in4p); 463 pcbsp = in4p->inp_sp; 464 break; 465 } 466 467 #if defined(INET6) 468 case AF_INET6: { 469 struct in6pcb *in6p = (struct in6pcb *)inph; 470 /* set spidx in pcb */ 471 *error = ipsec6_setspidx_in6pcb(m, in6p); 472 pcbsp = in6p->in6p_sp; 473 break; 474 } 475 #endif 476 default: 477 *error = EPFNOSUPPORT; 478 break; 479 } 480 if (*error) 481 return NULL; 482 483 KASSERT(pcbsp != NULL); 484 switch (dir) { 485 case IPSEC_DIR_INBOUND: 486 currsp = pcbsp->sp_in; 487 break; 488 case IPSEC_DIR_OUTBOUND: 489 currsp = pcbsp->sp_out; 490 break; 491 } 492 KASSERT(currsp != NULL); 493 494 if (pcbsp->priv) { /* when privilieged socket */ 495 switch (currsp->policy) { 496 case IPSEC_POLICY_BYPASS: 497 case IPSEC_POLICY_IPSEC: 498 KEY_SP_REF(currsp); 499 sp = currsp; 500 break; 501 502 case IPSEC_POLICY_ENTRUST: 503 /* look for a policy in SPD */ 504 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 505 if (sp == NULL) /* no SP found */ 506 sp = KEY_GET_DEFAULT_SP(af); 507 break; 508 509 default: 510 IPSECLOG(LOG_ERR, "Invalid policy for PCB %d\n", 511 currsp->policy); 512 *error = EINVAL; 513 return NULL; 514 } 515 } else { /* unpriv, SPD has policy */ 516 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 517 if (sp == NULL) { /* no SP found */ 518 switch (currsp->policy) { 519 case IPSEC_POLICY_BYPASS: 520 IPSECLOG(LOG_ERR, "Illegal policy for " 521 "non-priviliged defined %d\n", 522 currsp->policy); 523 *error = EINVAL; 524 return NULL; 525 526 case IPSEC_POLICY_ENTRUST: 527 sp = KEY_GET_DEFAULT_SP(af); 528 break; 529 530 case IPSEC_POLICY_IPSEC: 531 KEY_SP_REF(currsp); 532 sp = currsp; 533 break; 534 535 default: 536 IPSECLOG(LOG_ERR, "Invalid policy for " 537 "PCB %d\n", currsp->policy); 538 *error = EINVAL; 539 return NULL; 540 } 541 } 542 } 543 KASSERTMSG(sp != NULL, "null SP (priv %u policy %u", pcbsp->priv, 544 currsp->policy); 545 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 546 "DP (priv %u policy %u) allocates SP:%p (refcnt %u)\n", 547 pcbsp->priv, currsp->policy, sp, key_sp_refcnt(sp)); 548 ipsec_fillpcbcache(pcbsp, m, sp, dir); 549 return sp; 550 } 551 552 /* 553 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 554 * and return a pointer to SP. 555 * OUT: positive: a pointer to the entry for security policy leaf matched. 556 * NULL: no apropreate SP found, the following value is set to error. 557 * 0 : bypass 558 * EACCES : discard packet. 559 * ENOENT : ipsec_acquire() in progress, maybe. 560 * others : error occurred. 561 */ 562 struct secpolicy * 563 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 564 { 565 struct secpolicyindex spidx; 566 struct secpolicy *sp; 567 568 KASSERT(m != NULL); 569 KASSERT(error != NULL); 570 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 571 572 sp = NULL; 573 574 /* Make an index to look for a policy. */ 575 *error = ipsec_setspidx(m, &spidx, (flag & IP_FORWARDING) ? 0 : 1); 576 if (*error != 0) { 577 IPSECLOG(LOG_DEBUG, "setpidx failed, dir %u flag %u\n", dir, flag); 578 memset(&spidx, 0, sizeof (spidx)); 579 return NULL; 580 } 581 582 spidx.dir = dir; 583 584 if (key_havesp(dir)) { 585 sp = KEY_LOOKUP_SP_BYSPIDX(&spidx, dir); 586 } 587 588 if (sp == NULL) /* no SP found, use system default */ 589 sp = KEY_GET_DEFAULT_SP(spidx.dst.sa.sa_family); 590 KASSERT(sp != NULL); 591 return sp; 592 } 593 594 struct secpolicy * 595 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 596 struct inpcb *inp) 597 { 598 struct secpolicy *sp; 599 600 *error = 0; 601 602 if (inp == NULL) { 603 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 604 } else { 605 KASSERT(inp->inp_socket != NULL); 606 sp = ipsec_getpolicybysock(m, dir, (struct inpcb_hdr *)inp, error); 607 } 608 if (sp == NULL) { 609 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 610 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 611 return NULL; 612 } 613 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 614 switch (sp->policy) { 615 case IPSEC_POLICY_ENTRUST: 616 default: 617 printf("%s: invalid policy %u\n", __func__, sp->policy); 618 /* fall thru... */ 619 case IPSEC_POLICY_DISCARD: 620 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 621 *error = -EINVAL; /* packet is discarded by caller */ 622 break; 623 case IPSEC_POLICY_BYPASS: 624 case IPSEC_POLICY_NONE: 625 KEY_SP_UNREF(&sp); 626 sp = NULL; /* NB: force NULL result */ 627 break; 628 case IPSEC_POLICY_IPSEC: 629 KASSERT(sp->req != NULL); 630 break; 631 } 632 if (*error != 0) { 633 KEY_SP_UNREF(&sp); 634 sp = NULL; 635 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 636 } 637 return sp; 638 } 639 640 int 641 ipsec4_output(struct mbuf *m, struct inpcb *inp, int flags, 642 u_long *mtu, bool *natt_frag, bool *done) 643 { 644 struct secpolicy *sp = NULL; 645 int error, s; 646 647 /* 648 * Check the security policy (SP) for the packet and, if required, 649 * do IPsec-related processing. There are two cases here; the first 650 * time a packet is sent through it will be untagged and handled by 651 * ipsec4_checkpolicy(). If the packet is resubmitted to ip_output 652 * (e.g. after AH, ESP, etc. processing), there will be a tag to 653 * bypass the lookup and related policy checking. 654 */ 655 if (ipsec_outdone(m)) { 656 return 0; 657 } 658 s = splsoftnet(); 659 if (inp && ipsec_pcb_skip_ipsec(inp->inp_sp, IPSEC_DIR_OUTBOUND)) { 660 splx(s); 661 return 0; 662 } 663 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, inp); 664 665 /* 666 * There are four return cases: 667 * sp != NULL apply IPsec policy 668 * sp == NULL, error == 0 no IPsec handling needed 669 * sp == NULL, error == -EINVAL discard packet w/o error 670 * sp == NULL, error != 0 discard packet, report error 671 */ 672 if (sp == NULL) { 673 splx(s); 674 if (error) { 675 /* 676 * Hack: -EINVAL is used to signal that a packet 677 * should be silently discarded. This is typically 678 * because we asked key management for an SA and 679 * it was delayed (e.g. kicked up to IKE). 680 */ 681 if (error == -EINVAL) 682 error = 0; 683 m_freem(m); 684 *done = true; 685 return error; 686 } 687 /* No IPsec processing for this packet. */ 688 return 0; 689 } 690 691 /* 692 * Do delayed checksums now because we send before 693 * this is done in the normal processing path. 694 */ 695 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 696 in_delayed_cksum(m); 697 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 698 } 699 700 { 701 u_long _mtu = 0; 702 703 /* Note: callee frees mbuf */ 704 error = ipsec4_process_packet(m, sp->req, &_mtu); 705 706 if (error == 0 && _mtu != 0) { 707 /* 708 * NAT-T ESP fragmentation: do not do IPSec processing 709 * now, we will do it on each fragmented packet. 710 */ 711 *mtu = _mtu; 712 *natt_frag = true; 713 KEY_SP_UNREF(&sp); 714 splx(s); 715 return 0; 716 } 717 } 718 /* 719 * Preserve KAME behaviour: ENOENT can be returned 720 * when an SA acquire is in progress. Don't propagate 721 * this to user-level; it confuses applications. 722 * 723 * XXX this will go away when the SADB is redone. 724 */ 725 if (error == ENOENT) 726 error = 0; 727 KEY_SP_UNREF(&sp); 728 splx(s); 729 *done = true; 730 return error; 731 } 732 733 int 734 ipsec4_input(struct mbuf *m, int flags) 735 { 736 struct secpolicy *sp; 737 int error, s; 738 739 s = splsoftnet(); 740 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 741 if (sp == NULL) { 742 splx(s); 743 return EINVAL; 744 } 745 746 /* 747 * Check security policy against packet attributes. 748 */ 749 error = ipsec_in_reject(sp, m); 750 KEY_SP_UNREF(&sp); 751 splx(s); 752 if (error) { 753 return error; 754 } 755 756 if (flags == 0) { 757 /* We are done. */ 758 return 0; 759 } 760 761 /* 762 * Peek at the outbound SP for this packet to determine if 763 * it is a Fast Forward candidate. 764 */ 765 s = splsoftnet(); 766 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, NULL); 767 if (sp != NULL) { 768 m->m_flags &= ~M_CANFASTFWD; 769 KEY_SP_UNREF(&sp); 770 } 771 splx(s); 772 return 0; 773 } 774 775 int 776 ipsec4_forward(struct mbuf *m, int *destmtu) 777 { 778 /* 779 * If the packet is routed over IPsec tunnel, tell the 780 * originator the tunnel MTU. 781 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 782 * XXX quickhack!!! 783 */ 784 struct secpolicy *sp; 785 size_t ipsechdr; 786 int error; 787 788 sp = ipsec4_getpolicybyaddr(m, 789 IPSEC_DIR_OUTBOUND, IP_FORWARDING, &error); 790 if (sp == NULL) { 791 return EINVAL; 792 } 793 794 /* Count IPsec header size. */ 795 ipsechdr = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, NULL); 796 797 /* 798 * Find the correct route for outer IPv4 header, compute tunnel MTU. 799 */ 800 if (sp->req) { 801 struct route *ro; 802 struct rtentry *rt; 803 struct secasvar *sav = NULL; 804 805 error = key_checkrequest(sp->req, &sav); 806 if (error != 0) 807 return error; 808 ro = &sav->sah->sa_route; 809 rt = rtcache_validate(ro); 810 if (rt && rt->rt_ifp) { 811 *destmtu = rt->rt_rmx.rmx_mtu ? 812 rt->rt_rmx.rmx_mtu : rt->rt_ifp->if_mtu; 813 *destmtu -= ipsechdr; 814 } 815 rtcache_unref(rt, ro); 816 KEY_FREESAV(&sav); 817 } 818 KEY_SP_UNREF(&sp); 819 return 0; 820 } 821 822 #ifdef INET6 823 struct secpolicy * 824 ipsec6_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 825 struct in6pcb *in6p) 826 { 827 struct secpolicy *sp; 828 829 *error = 0; 830 831 if (in6p == NULL) { 832 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 833 } else { 834 KASSERT(in6p->in6p_socket != NULL); 835 sp = ipsec_getpolicybysock(m, dir, (struct inpcb_hdr *)in6p, error); 836 } 837 if (sp == NULL) { 838 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 839 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 840 return NULL; 841 } 842 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 843 switch (sp->policy) { 844 case IPSEC_POLICY_ENTRUST: 845 default: 846 printf("%s: invalid policy %u\n", __func__, sp->policy); 847 /* fall thru... */ 848 case IPSEC_POLICY_DISCARD: 849 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 850 *error = -EINVAL; /* packet is discarded by caller */ 851 break; 852 case IPSEC_POLICY_BYPASS: 853 case IPSEC_POLICY_NONE: 854 KEY_SP_UNREF(&sp); 855 sp = NULL; /* NB: force NULL result */ 856 break; 857 case IPSEC_POLICY_IPSEC: 858 KASSERT(sp->req != NULL); 859 break; 860 } 861 if (*error != 0) { 862 KEY_SP_UNREF(&sp); 863 sp = NULL; 864 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 865 } 866 return sp; 867 } 868 #endif /* INET6 */ 869 870 static int 871 ipsec4_setspidx_inpcb(struct mbuf *m, struct inpcb *pcb) 872 { 873 int error; 874 875 KASSERT(pcb != NULL); 876 KASSERT(pcb->inp_sp != NULL); 877 KASSERT(pcb->inp_sp->sp_out != NULL); 878 KASSERT(pcb->inp_sp->sp_in != NULL); 879 880 error = ipsec_setspidx(m, &pcb->inp_sp->sp_in->spidx, 1); 881 if (error == 0) { 882 pcb->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 883 pcb->inp_sp->sp_out->spidx = pcb->inp_sp->sp_in->spidx; 884 pcb->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 885 } else { 886 memset(&pcb->inp_sp->sp_in->spidx, 0, 887 sizeof(pcb->inp_sp->sp_in->spidx)); 888 memset(&pcb->inp_sp->sp_out->spidx, 0, 889 sizeof(pcb->inp_sp->sp_in->spidx)); 890 } 891 return error; 892 } 893 894 #ifdef INET6 895 static int 896 ipsec6_setspidx_in6pcb(struct mbuf *m, struct in6pcb *pcb) 897 { 898 struct secpolicyindex *spidx; 899 int error; 900 901 KASSERT(pcb != NULL); 902 KASSERT(pcb->in6p_sp != NULL); 903 KASSERT(pcb->in6p_sp->sp_out != NULL); 904 KASSERT(pcb->in6p_sp->sp_in != NULL); 905 906 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 907 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 908 909 spidx = &pcb->in6p_sp->sp_in->spidx; 910 error = ipsec_setspidx(m, spidx, 1); 911 if (error) 912 goto bad; 913 spidx->dir = IPSEC_DIR_INBOUND; 914 915 spidx = &pcb->in6p_sp->sp_out->spidx; 916 error = ipsec_setspidx(m, spidx, 1); 917 if (error) 918 goto bad; 919 spidx->dir = IPSEC_DIR_OUTBOUND; 920 921 return 0; 922 923 bad: 924 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 925 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 926 return error; 927 } 928 #endif 929 930 /* 931 * configure security policy index (src/dst/proto/sport/dport) 932 * by looking at the content of mbuf. 933 * the caller is responsible for error recovery (like clearing up spidx). 934 */ 935 static int 936 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 937 { 938 struct ip *ip = NULL; 939 struct ip ipbuf; 940 u_int v; 941 struct mbuf *n; 942 int len; 943 int error; 944 945 KASSERT(m != NULL); 946 947 /* 948 * validate m->m_pkthdr.len. we see incorrect length if we 949 * mistakenly call this function with inconsistent mbuf chain 950 * (like 4.4BSD tcp/udp processing). XXX should we panic here? 951 */ 952 len = 0; 953 for (n = m; n; n = n->m_next) 954 len += n->m_len; 955 if (m->m_pkthdr.len != len) { 956 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 957 "total of m_len(%d) != pkthdr.len(%d), ignored.\n", 958 len, m->m_pkthdr.len); 959 return EINVAL; 960 } 961 962 if (m->m_pkthdr.len < sizeof(struct ip)) { 963 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 964 "pkthdr.len(%d) < sizeof(struct ip), ignored.\n", 965 m->m_pkthdr.len); 966 return EINVAL; 967 } 968 969 if (m->m_len >= sizeof(*ip)) 970 ip = mtod(m, struct ip *); 971 else { 972 m_copydata(m, 0, sizeof(ipbuf), &ipbuf); 973 ip = &ipbuf; 974 } 975 v = ip->ip_v; 976 switch (v) { 977 case 4: 978 error = ipsec4_setspidx_ipaddr(m, spidx); 979 if (error) 980 return error; 981 ipsec4_get_ulp(m, spidx, needport); 982 return 0; 983 #ifdef INET6 984 case 6: 985 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 986 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 987 "pkthdr.len(%d) < sizeof(struct ip6_hdr), " 988 "ignored.\n", m->m_pkthdr.len); 989 return EINVAL; 990 } 991 error = ipsec6_setspidx_ipaddr(m, spidx); 992 if (error) 993 return error; 994 ipsec6_get_ulp(m, spidx, needport); 995 return 0; 996 #endif 997 default: 998 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 999 "unknown IP version %u, ignored.\n", v); 1000 return EINVAL; 1001 } 1002 } 1003 1004 static void 1005 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 1006 { 1007 u_int8_t nxt; 1008 int off; 1009 1010 /* sanity check */ 1011 KASSERT(m != NULL); 1012 KASSERTMSG(m->m_pkthdr.len >= sizeof(struct ip), "packet too short"); 1013 1014 /* NB: ip_input() flips it into host endian XXX need more checking */ 1015 if (m->m_len >= sizeof(struct ip)) { 1016 struct ip *ip = mtod(m, struct ip *); 1017 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 1018 goto done; 1019 off = ip->ip_hl << 2; 1020 nxt = ip->ip_p; 1021 } else { 1022 struct ip ih; 1023 1024 m_copydata(m, 0, sizeof (struct ip), &ih); 1025 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 1026 goto done; 1027 off = ih.ip_hl << 2; 1028 nxt = ih.ip_p; 1029 } 1030 1031 while (off < m->m_pkthdr.len) { 1032 struct ip6_ext ip6e; 1033 struct tcphdr th; 1034 struct udphdr uh; 1035 struct icmp icmph; 1036 1037 switch (nxt) { 1038 case IPPROTO_TCP: 1039 spidx->ul_proto = nxt; 1040 if (!needport) 1041 goto done_proto; 1042 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1043 goto done; 1044 m_copydata(m, off, sizeof (th), &th); 1045 spidx->src.sin.sin_port = th.th_sport; 1046 spidx->dst.sin.sin_port = th.th_dport; 1047 return; 1048 case IPPROTO_UDP: 1049 spidx->ul_proto = nxt; 1050 if (!needport) 1051 goto done_proto; 1052 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1053 goto done; 1054 m_copydata(m, off, sizeof (uh), &uh); 1055 spidx->src.sin.sin_port = uh.uh_sport; 1056 spidx->dst.sin.sin_port = uh.uh_dport; 1057 return; 1058 case IPPROTO_AH: 1059 if (m->m_pkthdr.len > off + sizeof(ip6e)) 1060 goto done; 1061 /* XXX sigh, this works but is totally bogus */ 1062 m_copydata(m, off, sizeof(ip6e), &ip6e); 1063 off += (ip6e.ip6e_len + 2) << 2; 1064 nxt = ip6e.ip6e_nxt; 1065 break; 1066 case IPPROTO_ICMP: 1067 spidx->ul_proto = nxt; 1068 if (off + sizeof(struct icmp) > m->m_pkthdr.len) 1069 return; 1070 m_copydata(m, off, sizeof(icmph), &icmph); 1071 ((struct sockaddr_in *)&spidx->src)->sin_port = 1072 htons((uint16_t)icmph.icmp_type); 1073 ((struct sockaddr_in *)&spidx->dst)->sin_port = 1074 htons((uint16_t)icmph.icmp_code); 1075 return; 1076 default: 1077 /* XXX intermediate headers??? */ 1078 spidx->ul_proto = nxt; 1079 goto done_proto; 1080 } 1081 } 1082 done: 1083 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1084 done_proto: 1085 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 1086 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 1087 } 1088 1089 /* assumes that m is sane */ 1090 static int 1091 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1092 { 1093 static const struct sockaddr_in template = { 1094 sizeof (struct sockaddr_in), 1095 AF_INET, 1096 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 1097 }; 1098 1099 spidx->src.sin = template; 1100 spidx->dst.sin = template; 1101 1102 if (m->m_len < sizeof (struct ip)) { 1103 m_copydata(m, offsetof(struct ip, ip_src), 1104 sizeof(struct in_addr), &spidx->src.sin.sin_addr); 1105 m_copydata(m, offsetof(struct ip, ip_dst), 1106 sizeof(struct in_addr), &spidx->dst.sin.sin_addr); 1107 } else { 1108 struct ip *ip = mtod(m, struct ip *); 1109 spidx->src.sin.sin_addr = ip->ip_src; 1110 spidx->dst.sin.sin_addr = ip->ip_dst; 1111 } 1112 1113 spidx->prefs = sizeof(struct in_addr) << 3; 1114 spidx->prefd = sizeof(struct in_addr) << 3; 1115 1116 return 0; 1117 } 1118 1119 #ifdef INET6 1120 static void 1121 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, 1122 int needport) 1123 { 1124 int off, nxt; 1125 struct tcphdr th; 1126 struct udphdr uh; 1127 struct icmp6_hdr icmph; 1128 1129 KASSERT(m != NULL); 1130 1131 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1132 printf("%s:\n", __func__); 1133 kdebug_mbuf(m); 1134 } 1135 1136 /* set default */ 1137 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1138 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 1139 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 1140 1141 nxt = -1; 1142 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 1143 if (off < 0 || m->m_pkthdr.len < off) 1144 return; 1145 1146 switch (nxt) { 1147 case IPPROTO_TCP: 1148 spidx->ul_proto = nxt; 1149 if (!needport) 1150 break; 1151 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1152 break; 1153 m_copydata(m, off, sizeof(th), &th); 1154 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 1155 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 1156 break; 1157 case IPPROTO_UDP: 1158 spidx->ul_proto = nxt; 1159 if (!needport) 1160 break; 1161 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1162 break; 1163 m_copydata(m, off, sizeof(uh), &uh); 1164 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 1165 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 1166 break; 1167 case IPPROTO_ICMPV6: 1168 spidx->ul_proto = nxt; 1169 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 1170 break; 1171 m_copydata(m, off, sizeof(icmph), &icmph); 1172 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 1173 htons((uint16_t)icmph.icmp6_type); 1174 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 1175 htons((uint16_t)icmph.icmp6_code); 1176 break; 1177 default: 1178 /* XXX intermediate headers??? */ 1179 spidx->ul_proto = nxt; 1180 break; 1181 } 1182 } 1183 1184 /* assumes that m is sane */ 1185 static int 1186 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1187 { 1188 struct ip6_hdr *ip6 = NULL; 1189 struct ip6_hdr ip6buf; 1190 struct sockaddr_in6 *sin6; 1191 1192 if (m->m_len >= sizeof(*ip6)) 1193 ip6 = mtod(m, struct ip6_hdr *); 1194 else { 1195 m_copydata(m, 0, sizeof(ip6buf), &ip6buf); 1196 ip6 = &ip6buf; 1197 } 1198 1199 sin6 = (struct sockaddr_in6 *)&spidx->src; 1200 memset(sin6, 0, sizeof(*sin6)); 1201 sin6->sin6_family = AF_INET6; 1202 sin6->sin6_len = sizeof(struct sockaddr_in6); 1203 memcpy(&sin6->sin6_addr, &ip6->ip6_src, sizeof(ip6->ip6_src)); 1204 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 1205 sin6->sin6_addr.s6_addr16[1] = 0; 1206 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 1207 } 1208 spidx->prefs = sizeof(struct in6_addr) << 3; 1209 1210 sin6 = (struct sockaddr_in6 *)&spidx->dst; 1211 memset(sin6, 0, sizeof(*sin6)); 1212 sin6->sin6_family = AF_INET6; 1213 sin6->sin6_len = sizeof(struct sockaddr_in6); 1214 memcpy(&sin6->sin6_addr, &ip6->ip6_dst, sizeof(ip6->ip6_dst)); 1215 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 1216 sin6->sin6_addr.s6_addr16[1] = 0; 1217 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 1218 } 1219 spidx->prefd = sizeof(struct in6_addr) << 3; 1220 1221 return 0; 1222 } 1223 #endif 1224 1225 static void 1226 ipsec_delpcbpolicy(struct inpcbpolicy *p) 1227 { 1228 1229 kmem_intr_free(p, sizeof(*p)); 1230 } 1231 1232 /* initialize policy in PCB */ 1233 int 1234 ipsec_init_policy(struct socket *so, struct inpcbpolicy **policy) 1235 { 1236 struct inpcbpolicy *new; 1237 1238 KASSERT(so != NULL); 1239 KASSERT(policy != NULL); 1240 1241 new = kmem_intr_zalloc(sizeof(*new), KM_NOSLEEP); 1242 if (new == NULL) { 1243 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1244 return ENOBUFS; 1245 } 1246 1247 if (IPSEC_PRIVILEGED_SO(so)) 1248 new->priv = 1; 1249 else 1250 new->priv = 0; 1251 1252 /* 1253 * These SPs are dummy. Never be used because the policy 1254 * is ENTRUST. See ipsec_getpolicybysock. 1255 */ 1256 new->sp_in = kmem_intr_zalloc(sizeof(struct secpolicy), KM_NOSLEEP); 1257 if (new->sp_in == NULL) { 1258 ipsec_delpcbpolicy(new); 1259 return ENOBUFS; 1260 } 1261 new->sp_in->state = IPSEC_SPSTATE_ALIVE; 1262 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 1263 new->sp_in->created = 0; /* Indicates dummy */ 1264 1265 new->sp_out = kmem_intr_zalloc(sizeof(struct secpolicy), KM_NOSLEEP); 1266 if (new->sp_out == NULL) { 1267 kmem_intr_free(new->sp_in, sizeof(struct secpolicy)); 1268 ipsec_delpcbpolicy(new); 1269 return ENOBUFS; 1270 } 1271 new->sp_out->state = IPSEC_SPSTATE_ALIVE; 1272 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 1273 new->sp_out->created = 0; /* Indicates dummy */ 1274 1275 *policy = new; 1276 1277 return 0; 1278 } 1279 1280 /* copy old ipsec policy into new */ 1281 int 1282 ipsec_copy_policy(const struct inpcbpolicy *old, struct inpcbpolicy *new) 1283 { 1284 struct secpolicy *sp; 1285 1286 sp = ipsec_deepcopy_policy(old->sp_in); 1287 if (sp) { 1288 KEY_SP_UNREF(&new->sp_in); 1289 new->sp_in = sp; 1290 } else 1291 return ENOBUFS; 1292 1293 sp = ipsec_deepcopy_policy(old->sp_out); 1294 if (sp) { 1295 KEY_SP_UNREF(&new->sp_out); 1296 new->sp_out = sp; 1297 } else 1298 return ENOBUFS; 1299 1300 new->priv = old->priv; 1301 1302 return 0; 1303 } 1304 1305 /* deep-copy a policy in PCB */ 1306 static struct secpolicy * 1307 ipsec_deepcopy_policy(const struct secpolicy *src) 1308 { 1309 struct ipsecrequest *newchain = NULL; 1310 const struct ipsecrequest *p; 1311 struct ipsecrequest **q; 1312 struct secpolicy *dst; 1313 1314 if (src == NULL) 1315 return NULL; 1316 dst = KEY_NEWSP(); 1317 if (dst == NULL) 1318 return NULL; 1319 1320 /* 1321 * deep-copy IPsec request chain. This is required since struct 1322 * ipsecrequest is not reference counted. 1323 */ 1324 q = &newchain; 1325 for (p = src->req; p; p = p->next) { 1326 *q = kmem_zalloc(sizeof(**q), KM_SLEEP); 1327 (*q)->next = NULL; 1328 1329 (*q)->saidx.proto = p->saidx.proto; 1330 (*q)->saidx.mode = p->saidx.mode; 1331 (*q)->level = p->level; 1332 (*q)->saidx.reqid = p->saidx.reqid; 1333 1334 memcpy(&(*q)->saidx.src, &p->saidx.src, sizeof((*q)->saidx.src)); 1335 memcpy(&(*q)->saidx.dst, &p->saidx.dst, sizeof((*q)->saidx.dst)); 1336 1337 (*q)->sp = dst; 1338 1339 q = &((*q)->next); 1340 } 1341 1342 dst->req = newchain; 1343 dst->state = src->state; 1344 dst->policy = src->policy; 1345 /* do not touch the refcnt fields */ 1346 1347 return dst; 1348 } 1349 1350 static void 1351 ipsec_destroy_policy(struct secpolicy *sp) 1352 { 1353 1354 if (sp->created == 0) 1355 /* It's dummy. We can simply free it */ 1356 kmem_intr_free(sp, sizeof(*sp)); 1357 else { 1358 /* 1359 * We cannot destroy here because it can be called in 1360 * softint. So mark the SP as DEAD and let the timer 1361 * destroy it. See key_timehandler_spd. 1362 */ 1363 sp->state = IPSEC_SPSTATE_DEAD; 1364 } 1365 } 1366 1367 /* set policy and ipsec request if present. */ 1368 static int 1369 ipsec_set_policy( 1370 struct secpolicy **policy, 1371 int optname, 1372 const void *request, 1373 size_t len, 1374 kauth_cred_t cred 1375 ) 1376 { 1377 const struct sadb_x_policy *xpl; 1378 struct secpolicy *newsp = NULL, *oldsp; 1379 int error; 1380 1381 KASSERT(!cpu_softintr_p()); 1382 1383 /* sanity check. */ 1384 if (policy == NULL || *policy == NULL || request == NULL) 1385 return EINVAL; 1386 if (len < sizeof(*xpl)) 1387 return EINVAL; 1388 xpl = (const struct sadb_x_policy *)request; 1389 1390 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1391 printf("%s: passed policy\n", __func__); 1392 kdebug_sadb_x_policy((const struct sadb_ext *)xpl); 1393 } 1394 1395 /* check policy type */ 1396 /* ipsec_set_policy() accepts IPSEC, ENTRUST and BYPASS. */ 1397 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 1398 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1399 return EINVAL; 1400 1401 /* check privileged socket */ 1402 if (xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1403 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPSEC, 1404 KAUTH_REQ_NETWORK_IPSEC_BYPASS, NULL, NULL, NULL); 1405 if (error) 1406 return (error); 1407 } 1408 1409 /* allocation new SP entry */ 1410 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1411 return error; 1412 1413 key_init_sp(newsp); 1414 newsp->created = time_uptime; 1415 /* Insert the global list for SPs for sockets */ 1416 key_socksplist_add(newsp); 1417 1418 /* clear old SP and set new SP */ 1419 oldsp = *policy; 1420 *policy = newsp; 1421 ipsec_destroy_policy(oldsp); 1422 1423 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1424 printf("%s: new policy\n", __func__); 1425 kdebug_secpolicy(newsp); 1426 } 1427 1428 return 0; 1429 } 1430 1431 static int 1432 ipsec_get_policy(struct secpolicy *policy, struct mbuf **mp) 1433 { 1434 1435 /* sanity check. */ 1436 if (policy == NULL || mp == NULL) 1437 return EINVAL; 1438 1439 *mp = key_sp2msg(policy); 1440 if (!*mp) { 1441 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1442 return ENOBUFS; 1443 } 1444 1445 (*mp)->m_type = MT_DATA; 1446 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1447 printf("%s:\n", __func__); 1448 kdebug_mbuf(*mp); 1449 } 1450 1451 return 0; 1452 } 1453 1454 int 1455 ipsec4_set_policy(struct inpcb *inp, int optname, const void *request, 1456 size_t len, kauth_cred_t cred) 1457 { 1458 const struct sadb_x_policy *xpl; 1459 struct secpolicy **policy; 1460 1461 KASSERT(!cpu_softintr_p()); 1462 KASSERT(inp_locked(inp)); 1463 1464 /* sanity check. */ 1465 if (inp == NULL || request == NULL) 1466 return EINVAL; 1467 if (len < sizeof(*xpl)) 1468 return EINVAL; 1469 xpl = (const struct sadb_x_policy *)request; 1470 1471 KASSERT(inp->inp_sp != NULL); 1472 1473 /* select direction */ 1474 switch (xpl->sadb_x_policy_dir) { 1475 case IPSEC_DIR_INBOUND: 1476 policy = &inp->inp_sp->sp_in; 1477 break; 1478 case IPSEC_DIR_OUTBOUND: 1479 policy = &inp->inp_sp->sp_out; 1480 break; 1481 default: 1482 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1483 xpl->sadb_x_policy_dir); 1484 return EINVAL; 1485 } 1486 1487 return ipsec_set_policy(policy, optname, request, len, cred); 1488 } 1489 1490 int 1491 ipsec4_get_policy(struct inpcb *inp, const void *request, size_t len, 1492 struct mbuf **mp) 1493 { 1494 const struct sadb_x_policy *xpl; 1495 struct secpolicy *policy; 1496 1497 /* sanity check. */ 1498 if (inp == NULL || request == NULL || mp == NULL) 1499 return EINVAL; 1500 KASSERT(inp->inp_sp != NULL); 1501 if (len < sizeof(*xpl)) 1502 return EINVAL; 1503 xpl = (const struct sadb_x_policy *)request; 1504 1505 /* select direction */ 1506 switch (xpl->sadb_x_policy_dir) { 1507 case IPSEC_DIR_INBOUND: 1508 policy = inp->inp_sp->sp_in; 1509 break; 1510 case IPSEC_DIR_OUTBOUND: 1511 policy = inp->inp_sp->sp_out; 1512 break; 1513 default: 1514 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1515 xpl->sadb_x_policy_dir); 1516 return EINVAL; 1517 } 1518 1519 return ipsec_get_policy(policy, mp); 1520 } 1521 1522 /* delete policy in PCB */ 1523 int 1524 ipsec4_delete_pcbpolicy(struct inpcb *inp) 1525 { 1526 1527 KASSERT(inp != NULL); 1528 1529 if (inp->inp_sp == NULL) 1530 return 0; 1531 1532 if (inp->inp_sp->sp_in != NULL) 1533 ipsec_destroy_policy(inp->inp_sp->sp_in); 1534 1535 if (inp->inp_sp->sp_out != NULL) 1536 ipsec_destroy_policy(inp->inp_sp->sp_out); 1537 1538 ipsec_invalpcbcache(inp->inp_sp, IPSEC_DIR_ANY); 1539 1540 ipsec_delpcbpolicy(inp->inp_sp); 1541 inp->inp_sp = NULL; 1542 1543 return 0; 1544 } 1545 1546 #ifdef INET6 1547 int 1548 ipsec6_set_policy(struct in6pcb *in6p, int optname, const void *request, 1549 size_t len, kauth_cred_t cred) 1550 { 1551 const struct sadb_x_policy *xpl; 1552 struct secpolicy **policy; 1553 1554 KASSERT(!cpu_softintr_p()); 1555 KASSERT(in6p_locked(in6p)); 1556 1557 /* sanity check. */ 1558 if (in6p == NULL || request == NULL) 1559 return EINVAL; 1560 if (len < sizeof(*xpl)) 1561 return EINVAL; 1562 xpl = (const struct sadb_x_policy *)request; 1563 1564 /* select direction */ 1565 switch (xpl->sadb_x_policy_dir) { 1566 case IPSEC_DIR_INBOUND: 1567 policy = &in6p->in6p_sp->sp_in; 1568 break; 1569 case IPSEC_DIR_OUTBOUND: 1570 policy = &in6p->in6p_sp->sp_out; 1571 break; 1572 default: 1573 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1574 xpl->sadb_x_policy_dir); 1575 return EINVAL; 1576 } 1577 1578 return ipsec_set_policy(policy, optname, request, len, cred); 1579 } 1580 1581 int 1582 ipsec6_get_policy(struct in6pcb *in6p, const void *request, size_t len, 1583 struct mbuf **mp) 1584 { 1585 const struct sadb_x_policy *xpl; 1586 struct secpolicy *policy; 1587 1588 /* sanity check. */ 1589 if (in6p == NULL || request == NULL || mp == NULL) 1590 return EINVAL; 1591 KASSERT(in6p->in6p_sp != NULL); 1592 if (len < sizeof(*xpl)) 1593 return EINVAL; 1594 xpl = (const struct sadb_x_policy *)request; 1595 1596 /* select direction */ 1597 switch (xpl->sadb_x_policy_dir) { 1598 case IPSEC_DIR_INBOUND: 1599 policy = in6p->in6p_sp->sp_in; 1600 break; 1601 case IPSEC_DIR_OUTBOUND: 1602 policy = in6p->in6p_sp->sp_out; 1603 break; 1604 default: 1605 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1606 xpl->sadb_x_policy_dir); 1607 return EINVAL; 1608 } 1609 1610 return ipsec_get_policy(policy, mp); 1611 } 1612 1613 int 1614 ipsec6_delete_pcbpolicy(struct in6pcb *in6p) 1615 { 1616 1617 KASSERT(in6p != NULL); 1618 1619 if (in6p->in6p_sp == NULL) 1620 return 0; 1621 1622 if (in6p->in6p_sp->sp_in != NULL) 1623 ipsec_destroy_policy(in6p->in6p_sp->sp_in); 1624 1625 if (in6p->in6p_sp->sp_out != NULL) 1626 ipsec_destroy_policy(in6p->in6p_sp->sp_out); 1627 1628 ipsec_invalpcbcache(in6p->in6p_sp, IPSEC_DIR_ANY); 1629 1630 ipsec_delpcbpolicy(in6p->in6p_sp); 1631 in6p->in6p_sp = NULL; 1632 1633 return 0; 1634 } 1635 #endif 1636 1637 /* 1638 * return current level. 1639 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1640 */ 1641 u_int 1642 ipsec_get_reqlevel(const struct ipsecrequest *isr) 1643 { 1644 u_int level = 0; 1645 u_int esp_trans_deflev, esp_net_deflev; 1646 u_int ah_trans_deflev, ah_net_deflev; 1647 1648 KASSERT(isr != NULL); 1649 KASSERT(isr->sp != NULL); 1650 KASSERTMSG( 1651 isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1652 "af family mismatch, src %u, dst %u", 1653 isr->sp->spidx.src.sa.sa_family, isr->sp->spidx.dst.sa.sa_family); 1654 1655 /* XXX note that we have ipseclog() expanded here - code sync issue */ 1656 #define IPSEC_CHECK_DEFAULT(lev) \ 1657 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1658 && (lev) != IPSEC_LEVEL_UNIQUE) ? \ 1659 (ipsec_debug ? log(LOG_INFO, "fixed system default level " #lev \ 1660 ":%d->%d\n", (lev), IPSEC_LEVEL_REQUIRE) : (void)0), \ 1661 (lev) = IPSEC_LEVEL_REQUIRE, (lev) \ 1662 : (lev)) 1663 1664 /* set default level */ 1665 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1666 #ifdef INET 1667 case AF_INET: 1668 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_trans_deflev); 1669 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_net_deflev); 1670 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_trans_deflev); 1671 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_net_deflev); 1672 break; 1673 #endif 1674 #ifdef INET6 1675 case AF_INET6: 1676 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_trans_deflev); 1677 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_net_deflev); 1678 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_trans_deflev); 1679 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_net_deflev); 1680 break; 1681 #endif /* INET6 */ 1682 default: 1683 panic("%s: unknown af %u", __func__, 1684 isr->sp->spidx.src.sa.sa_family); 1685 } 1686 1687 #undef IPSEC_CHECK_DEFAULT 1688 1689 /* set level */ 1690 switch (isr->level) { 1691 case IPSEC_LEVEL_DEFAULT: 1692 switch (isr->saidx.proto) { 1693 case IPPROTO_ESP: 1694 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1695 level = esp_net_deflev; 1696 else 1697 level = esp_trans_deflev; 1698 break; 1699 case IPPROTO_AH: 1700 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1701 level = ah_net_deflev; 1702 else 1703 level = ah_trans_deflev; 1704 break; 1705 case IPPROTO_IPCOMP: 1706 /* 1707 * we don't really care, as IPcomp document says that 1708 * we shouldn't compress small packets 1709 */ 1710 level = IPSEC_LEVEL_USE; 1711 break; 1712 default: 1713 panic("%s: Illegal protocol defined %u", __func__, 1714 isr->saidx.proto); 1715 } 1716 break; 1717 1718 case IPSEC_LEVEL_USE: 1719 case IPSEC_LEVEL_REQUIRE: 1720 level = isr->level; 1721 break; 1722 case IPSEC_LEVEL_UNIQUE: 1723 level = IPSEC_LEVEL_REQUIRE; 1724 break; 1725 1726 default: 1727 panic("%s: Illegal IPsec level %u", __func__, isr->level); 1728 } 1729 1730 return level; 1731 } 1732 1733 /* 1734 * Check security policy requirements against the actual 1735 * packet contents. Return one if the packet should be 1736 * reject as "invalid"; otherwiser return zero to have the 1737 * packet treated as "valid". 1738 * 1739 * OUT: 1740 * 0: valid 1741 * 1: invalid 1742 */ 1743 int 1744 ipsec_in_reject(const struct secpolicy *sp, const struct mbuf *m) 1745 { 1746 struct ipsecrequest *isr; 1747 1748 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1749 printf("%s: using SP\n", __func__); 1750 kdebug_secpolicy(sp); 1751 } 1752 1753 /* check policy */ 1754 switch (sp->policy) { 1755 case IPSEC_POLICY_DISCARD: 1756 return 1; 1757 case IPSEC_POLICY_BYPASS: 1758 case IPSEC_POLICY_NONE: 1759 return 0; 1760 } 1761 1762 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1763 "invalid policy %u", sp->policy); 1764 1765 /* XXX should compare policy against ipsec header history */ 1766 1767 for (isr = sp->req; isr != NULL; isr = isr->next) { 1768 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1769 continue; 1770 switch (isr->saidx.proto) { 1771 case IPPROTO_ESP: 1772 if ((m->m_flags & M_DECRYPTED) == 0) { 1773 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1774 "ESP m_flags:%x\n", m->m_flags); 1775 return 1; 1776 } 1777 break; 1778 case IPPROTO_AH: 1779 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1780 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1781 "AH m_flags:%x\n", m->m_flags); 1782 return 1; 1783 } 1784 break; 1785 case IPPROTO_IPCOMP: 1786 /* 1787 * we don't really care, as IPcomp document 1788 * says that we shouldn't compress small 1789 * packets, IPComp policy should always be 1790 * treated as being in "use" level. 1791 */ 1792 break; 1793 } 1794 } 1795 return 0; /* valid */ 1796 } 1797 1798 /* 1799 * Check AH/ESP integrity. 1800 * This function is called from tcp_input(), udp_input(), 1801 * and {ah,esp}4_input for tunnel mode 1802 */ 1803 int 1804 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1805 { 1806 struct secpolicy *sp; 1807 int error; 1808 int result; 1809 1810 KASSERT(m != NULL); 1811 1812 /* get SP for this packet. 1813 * When we are called from ip_forward(), we call 1814 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1815 */ 1816 if (inp == NULL) 1817 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1818 else 1819 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1820 (struct inpcb_hdr *)inp, &error); 1821 1822 if (sp != NULL) { 1823 result = ipsec_in_reject(sp, m); 1824 if (result) 1825 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1826 KEY_SP_UNREF(&sp); 1827 } else { 1828 result = 0; /* XXX should be panic ? 1829 * -> No, there may be error. */ 1830 } 1831 return result; 1832 } 1833 1834 1835 #ifdef INET6 1836 /* 1837 * Check AH/ESP integrity. 1838 * This function is called from tcp6_input(), udp6_input(), 1839 * and {ah,esp}6_input for tunnel mode 1840 */ 1841 int 1842 ipsec6_in_reject(struct mbuf *m, struct in6pcb *in6p) 1843 { 1844 struct secpolicy *sp = NULL; 1845 int error; 1846 int result; 1847 1848 KASSERT(m != NULL); 1849 1850 /* get SP for this packet. 1851 * When we are called from ip_forward(), we call 1852 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1853 */ 1854 if (in6p == NULL) 1855 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1856 else 1857 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1858 (struct inpcb_hdr *)in6p, 1859 &error); 1860 1861 if (sp != NULL) { 1862 result = ipsec_in_reject(sp, m); 1863 if (result) 1864 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1865 KEY_SP_UNREF(&sp); 1866 } else { 1867 result = 0; 1868 } 1869 return result; 1870 } 1871 #endif 1872 1873 /* 1874 * compute the byte size to be occupied by IPsec header. 1875 * in case it is tunneled, it includes the size of outer IP header. 1876 * NOTE: SP passed is free in this function. 1877 */ 1878 static size_t 1879 ipsec_hdrsiz(const struct secpolicy *sp) 1880 { 1881 struct ipsecrequest *isr; 1882 size_t siz; 1883 1884 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1885 printf("%s: using SP\n", __func__); 1886 kdebug_secpolicy(sp); 1887 } 1888 1889 switch (sp->policy) { 1890 case IPSEC_POLICY_DISCARD: 1891 case IPSEC_POLICY_BYPASS: 1892 case IPSEC_POLICY_NONE: 1893 return 0; 1894 } 1895 1896 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1897 "invalid policy %u", sp->policy); 1898 1899 siz = 0; 1900 for (isr = sp->req; isr != NULL; isr = isr->next) { 1901 size_t clen = 0; 1902 struct secasvar *sav = NULL; 1903 int error; 1904 1905 switch (isr->saidx.proto) { 1906 case IPPROTO_ESP: 1907 error = key_checkrequest(isr, &sav); 1908 if (error == 0) { 1909 clen = esp_hdrsiz(sav); 1910 KEY_FREESAV(&sav); 1911 } else 1912 clen = esp_hdrsiz(NULL); 1913 break; 1914 case IPPROTO_AH: 1915 error = key_checkrequest(isr, &sav); 1916 if (error == 0) { 1917 clen = ah_hdrsiz(sav); 1918 KEY_FREESAV(&sav); 1919 } else 1920 clen = ah_hdrsiz(NULL); 1921 break; 1922 case IPPROTO_IPCOMP: 1923 clen = sizeof(struct ipcomp); 1924 break; 1925 } 1926 1927 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1928 switch (isr->saidx.dst.sa.sa_family) { 1929 case AF_INET: 1930 clen += sizeof(struct ip); 1931 break; 1932 #ifdef INET6 1933 case AF_INET6: 1934 clen += sizeof(struct ip6_hdr); 1935 break; 1936 #endif 1937 default: 1938 IPSECLOG(LOG_ERR, "unknown AF %d in " 1939 "IPsec tunnel SA\n", 1940 ((const struct sockaddr *)&isr->saidx.dst) 1941 ->sa_family); 1942 break; 1943 } 1944 } 1945 siz += clen; 1946 } 1947 1948 return siz; 1949 } 1950 1951 /* This function is called from ip_forward() and ipsec4_hdrsize_tcp(). */ 1952 size_t 1953 ipsec4_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1954 { 1955 struct secpolicy *sp; 1956 int error; 1957 size_t size; 1958 1959 KASSERT(m != NULL); 1960 KASSERTMSG(inp == NULL || inp->inp_socket != NULL, "socket w/o inpcb"); 1961 1962 /* get SP for this packet. 1963 * When we are called from ip_forward(), we call 1964 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1965 */ 1966 if (inp == NULL) 1967 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1968 else 1969 sp = ipsec_getpolicybysock(m, dir, 1970 (struct inpcb_hdr *)inp, &error); 1971 1972 if (sp != NULL) { 1973 size = ipsec_hdrsiz(sp); 1974 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%lu.\n", 1975 (unsigned long)size); 1976 1977 KEY_SP_UNREF(&sp); 1978 } else { 1979 size = 0; /* XXX should be panic ? */ 1980 } 1981 return size; 1982 } 1983 1984 #ifdef INET6 1985 /* This function is called from ipsec6_hdrsize_tcp(), 1986 * and maybe from ip6_forward.() 1987 */ 1988 size_t 1989 ipsec6_hdrsiz(struct mbuf *m, u_int dir, struct in6pcb *in6p) 1990 { 1991 struct secpolicy *sp; 1992 int error; 1993 size_t size; 1994 1995 KASSERT(m != NULL); 1996 KASSERTMSG(in6p == NULL || in6p->in6p_socket != NULL, 1997 "socket w/o inpcb"); 1998 1999 /* get SP for this packet */ 2000 /* XXX Is it right to call with IP_FORWARDING. */ 2001 if (in6p == NULL) 2002 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 2003 else 2004 sp = ipsec_getpolicybysock(m, dir, 2005 (struct inpcb_hdr *)in6p, 2006 &error); 2007 2008 if (sp == NULL) 2009 return 0; 2010 size = ipsec_hdrsiz(sp); 2011 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%zu.\n", size); 2012 KEY_SP_UNREF(&sp); 2013 2014 return size; 2015 } 2016 #endif /*INET6*/ 2017 2018 /* 2019 * Check the variable replay window. 2020 * ipsec_chkreplay() performs replay check before ICV verification. 2021 * ipsec_updatereplay() updates replay bitmap. This must be called after 2022 * ICV verification (it also performs replay check, which is usually done 2023 * beforehand). 2024 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 2025 * 2026 * based on RFC 2401. 2027 */ 2028 int 2029 ipsec_chkreplay(u_int32_t seq, const struct secasvar *sav) 2030 { 2031 const struct secreplay *replay; 2032 u_int32_t diff; 2033 int fr; 2034 u_int32_t wsizeb; /* constant: bits of window size */ 2035 int frlast; /* constant: last frame */ 2036 2037 IPSEC_SPLASSERT_SOFTNET(__func__); 2038 2039 KASSERT(sav != NULL); 2040 KASSERT(sav->replay != NULL); 2041 2042 replay = sav->replay; 2043 2044 if (replay->wsize == 0) 2045 return 1; /* no need to check replay. */ 2046 2047 /* constant */ 2048 frlast = replay->wsize - 1; 2049 wsizeb = replay->wsize << 3; 2050 2051 /* sequence number of 0 is invalid */ 2052 if (seq == 0) 2053 return 0; 2054 2055 /* first time is always okay */ 2056 if (replay->count == 0) 2057 return 1; 2058 2059 if (seq > replay->lastseq) { 2060 /* larger sequences are okay */ 2061 return 1; 2062 } else { 2063 /* seq is equal or less than lastseq. */ 2064 diff = replay->lastseq - seq; 2065 2066 /* over range to check, i.e. too old or wrapped */ 2067 if (diff >= wsizeb) 2068 return 0; 2069 2070 fr = frlast - diff / 8; 2071 2072 /* this packet already seen ? */ 2073 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2074 return 0; 2075 2076 /* out of order but good */ 2077 return 1; 2078 } 2079 } 2080 2081 /* 2082 * check replay counter whether to update or not. 2083 * OUT: 0: OK 2084 * 1: NG 2085 */ 2086 int 2087 ipsec_updatereplay(u_int32_t seq, const struct secasvar *sav) 2088 { 2089 struct secreplay *replay; 2090 u_int32_t diff; 2091 int fr; 2092 u_int32_t wsizeb; /* constant: bits of window size */ 2093 int frlast; /* constant: last frame */ 2094 char buf[INET6_ADDRSTRLEN]; 2095 2096 IPSEC_SPLASSERT_SOFTNET(__func__); 2097 2098 KASSERT(sav != NULL); 2099 KASSERT(sav->replay != NULL); 2100 2101 replay = sav->replay; 2102 2103 if (replay->wsize == 0) 2104 goto ok; /* no need to check replay. */ 2105 2106 /* constant */ 2107 frlast = replay->wsize - 1; 2108 wsizeb = replay->wsize << 3; 2109 2110 /* sequence number of 0 is invalid */ 2111 if (seq == 0) 2112 return 1; 2113 2114 /* first time */ 2115 if (replay->count == 0) { 2116 replay->lastseq = seq; 2117 memset(replay->bitmap, 0, replay->wsize); 2118 (replay->bitmap)[frlast] = 1; 2119 goto ok; 2120 } 2121 2122 if (seq > replay->lastseq) { 2123 /* seq is larger than lastseq. */ 2124 diff = seq - replay->lastseq; 2125 2126 /* new larger sequence number */ 2127 if (diff < wsizeb) { 2128 /* In window */ 2129 /* set bit for this packet */ 2130 vshiftl(replay->bitmap, diff, replay->wsize); 2131 (replay->bitmap)[frlast] |= 1; 2132 } else { 2133 /* this packet has a "way larger" */ 2134 memset(replay->bitmap, 0, replay->wsize); 2135 (replay->bitmap)[frlast] = 1; 2136 } 2137 replay->lastseq = seq; 2138 2139 /* larger is good */ 2140 } else { 2141 /* seq is equal or less than lastseq. */ 2142 diff = replay->lastseq - seq; 2143 2144 /* over range to check, i.e. too old or wrapped */ 2145 if (diff >= wsizeb) 2146 return 1; 2147 2148 fr = frlast - diff / 8; 2149 2150 /* this packet already seen ? */ 2151 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2152 return 1; 2153 2154 /* mark as seen */ 2155 (replay->bitmap)[fr] |= (1 << (diff % 8)); 2156 2157 /* out of order but good */ 2158 } 2159 2160 ok: 2161 if (replay->count == ~0) { 2162 2163 /* set overflow flag */ 2164 replay->overflow++; 2165 2166 /* don't increment, no more packets accepted */ 2167 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 2168 return 1; 2169 2170 IPSECLOG(LOG_WARNING, "replay counter made %d cycle. %s\n", 2171 replay->overflow, ipsec_logsastr(sav, buf, sizeof(buf))); 2172 } 2173 2174 replay->count++; 2175 2176 return 0; 2177 } 2178 2179 /* 2180 * shift variable length bunffer to left. 2181 * IN: bitmap: pointer to the buffer 2182 * nbit: the number of to shift. 2183 * wsize: buffer size (bytes). 2184 */ 2185 static void 2186 vshiftl(unsigned char *bitmap, int nbit, int wsize) 2187 { 2188 int s, j, i; 2189 unsigned char over; 2190 2191 for (j = 0; j < nbit; j += 8) { 2192 s = (nbit - j < 8) ? (nbit - j): 8; 2193 bitmap[0] <<= s; 2194 for (i = 1; i < wsize; i++) { 2195 over = (bitmap[i] >> (8 - s)); 2196 bitmap[i] <<= s; 2197 bitmap[i-1] |= over; 2198 } 2199 } 2200 2201 return; 2202 } 2203 2204 /* Return a printable string for the address. */ 2205 const char * 2206 ipsec_address(const union sockaddr_union *sa, char *buf, size_t size) 2207 { 2208 switch (sa->sa.sa_family) { 2209 #if INET 2210 case AF_INET: 2211 in_print(buf, size, &sa->sin.sin_addr); 2212 return buf; 2213 #endif /* INET */ 2214 2215 #if INET6 2216 case AF_INET6: 2217 in6_print(buf, size, &sa->sin6.sin6_addr); 2218 return buf; 2219 #endif /* INET6 */ 2220 2221 default: 2222 return "(unknown address family)"; 2223 } 2224 } 2225 2226 const char * 2227 ipsec_logsastr(const struct secasvar *sav, char *buf, size_t size) 2228 { 2229 const struct secasindex *saidx = &sav->sah->saidx; 2230 char sbuf[IPSEC_ADDRSTRLEN], dbuf[IPSEC_ADDRSTRLEN]; 2231 2232 KASSERTMSG(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 2233 "af family mismatch, src %u, dst %u", 2234 saidx->src.sa.sa_family, saidx->dst.sa.sa_family); 2235 2236 snprintf(buf, size, "SA(SPI=%u src=%s dst=%s)", 2237 (u_int32_t)ntohl(sav->spi), 2238 ipsec_address(&saidx->src, sbuf, sizeof(sbuf)), 2239 ipsec_address(&saidx->dst, dbuf, sizeof(dbuf))); 2240 2241 return buf; 2242 } 2243 2244 void 2245 ipsec_dumpmbuf(struct mbuf *m) 2246 { 2247 int totlen; 2248 int i; 2249 u_char *p; 2250 2251 totlen = 0; 2252 printf("---\n"); 2253 while (m) { 2254 p = mtod(m, u_char *); 2255 for (i = 0; i < m->m_len; i++) { 2256 printf("%02x ", p[i]); 2257 totlen++; 2258 if (totlen % 16 == 0) 2259 printf("\n"); 2260 } 2261 m = m->m_next; 2262 } 2263 if (totlen % 16 != 0) 2264 printf("\n"); 2265 printf("---\n"); 2266 } 2267 2268 #ifdef INET6 2269 struct secpolicy * 2270 ipsec6_check_policy(struct mbuf *m, struct in6pcb *in6p, 2271 int flags, int *needipsecp, int *errorp) 2272 { 2273 struct secpolicy *sp = NULL; 2274 int s; 2275 int error = 0; 2276 int needipsec = 0; 2277 2278 if (!ipsec_outdone(m)) { 2279 s = splsoftnet(); 2280 if (in6p != NULL && 2281 ipsec_pcb_skip_ipsec(in6p->in6p_sp, IPSEC_DIR_OUTBOUND)) { 2282 splx(s); 2283 goto skippolicycheck; 2284 } 2285 sp = ipsec6_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error,in6p); 2286 2287 /* 2288 * There are four return cases: 2289 * sp != NULL apply IPsec policy 2290 * sp == NULL, error == 0 no IPsec handling needed 2291 * sp == NULL, error == -EINVAL discard packet w/o error 2292 * sp == NULL, error != 0 discard packet, report error 2293 */ 2294 2295 splx(s); 2296 if (sp == NULL) { 2297 /* 2298 * Caller must check the error return to see if it needs to discard 2299 * the packet. 2300 */ 2301 needipsec = 0; 2302 } else { 2303 needipsec = 1; 2304 } 2305 } 2306 skippolicycheck:; 2307 2308 *errorp = error; 2309 *needipsecp = needipsec; 2310 return sp; 2311 } 2312 2313 int 2314 ipsec6_input(struct mbuf *m) 2315 { 2316 struct secpolicy *sp; 2317 int s, error; 2318 2319 s = splsoftnet(); 2320 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 2321 if (sp != NULL) { 2322 /* 2323 * Check security policy against packet 2324 * attributes. 2325 */ 2326 error = ipsec_in_reject(sp, m); 2327 KEY_SP_UNREF(&sp); 2328 } else { 2329 /* XXX error stat??? */ 2330 error = EINVAL; 2331 IPSECLOG(LOG_DEBUG, "no SP, packet discarded\n");/*XXX*/ 2332 } 2333 splx(s); 2334 2335 return error; 2336 } 2337 #endif /* INET6 */ 2338 2339 2340 2341 /* XXX this stuff doesn't belong here... */ 2342 2343 static struct xformsw *xforms = NULL; 2344 2345 /* 2346 * Register a transform; typically at system startup. 2347 */ 2348 void 2349 xform_register(struct xformsw *xsp) 2350 { 2351 xsp->xf_next = xforms; 2352 xforms = xsp; 2353 } 2354 2355 /* 2356 * Initialize transform support in an sav. 2357 */ 2358 int 2359 xform_init(struct secasvar *sav, int xftype) 2360 { 2361 struct xformsw *xsp; 2362 2363 if (sav->tdb_xform != NULL) /* previously initialized */ 2364 return 0; 2365 for (xsp = xforms; xsp; xsp = xsp->xf_next) 2366 if (xsp->xf_type == xftype) 2367 return (*xsp->xf_init)(sav, xsp); 2368 2369 IPSECLOG(LOG_DEBUG, "no match for xform type %d\n", xftype); 2370 return EINVAL; 2371 } 2372 2373 void 2374 nat_t_ports_get(struct mbuf *m, u_int16_t *dport, u_int16_t *sport) { 2375 struct m_tag *tag; 2376 2377 if ((tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL))) { 2378 *sport = ((u_int16_t *)(tag + 1))[0]; 2379 *dport = ((u_int16_t *)(tag + 1))[1]; 2380 } else 2381 *sport = *dport = 0; 2382 } 2383 2384 /* 2385 * XXXJRT This should be done as a protosw init call. 2386 */ 2387 void 2388 ipsec_attach(void) 2389 { 2390 2391 ipsecstat_percpu = percpu_alloc(sizeof(uint64_t) * IPSEC_NSTATS); 2392 2393 sysctl_net_inet_ipsec_setup(NULL); 2394 #ifdef INET6 2395 sysctl_net_inet6_ipsec6_setup(NULL); 2396 #endif 2397 2398 ah_attach(); 2399 esp_attach(); 2400 ipcomp_attach(); 2401 ipe4_attach(); 2402 #ifdef TCP_SIGNATURE 2403 tcpsignature_attach(); 2404 #endif 2405 } 2406
Indexes created Sun Sep 21 20:09:37 GMT 2025