ipsec.c revision 1.116
1 /* $NetBSD: ipsec.c,v 1.116 2017/08/03 06:32:51 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 1.116 2017/08/03 06:32:51 ozaki-r Exp $"); 36 37 /* 38 * IPsec controller part. 39 */ 40 41 #if defined(_KERNEL_OPT) 42 #include "opt_inet.h" 43 #include "opt_ipsec.h" 44 #endif 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/mbuf.h> 49 #include <sys/domain.h> 50 #include <sys/protosw.h> 51 #include <sys/socket.h> 52 #include <sys/socketvar.h> 53 #include <sys/errno.h> 54 #include <sys/time.h> 55 #include <sys/kernel.h> 56 #include <sys/syslog.h> 57 #include <sys/sysctl.h> 58 #include <sys/proc.h> 59 #include <sys/kauth.h> 60 #include <sys/cpu.h> 61 #include <sys/kmem.h> 62 #include <sys/pserialize.h> 63 64 #include <net/if.h> 65 #include <net/route.h> 66 67 #include <netinet/in.h> 68 #include <netinet/in_systm.h> 69 #include <netinet/ip.h> 70 #include <netinet/ip_var.h> 71 #include <netinet/in_var.h> 72 #include <netinet/udp.h> 73 #include <netinet/udp_var.h> 74 #include <netinet/tcp.h> 75 #include <netinet/udp.h> 76 #include <netinet/ip_icmp.h> 77 #include <netinet/ip_private.h> 78 79 #include <netinet/ip6.h> 80 #ifdef INET6 81 #include <netinet6/ip6_var.h> 82 #endif 83 #include <netinet/in_pcb.h> 84 #ifdef INET6 85 #include <netinet6/in6_pcb.h> 86 #include <netinet/icmp6.h> 87 #endif 88 89 #include <netipsec/ipsec.h> 90 #include <netipsec/ipsec_var.h> 91 #include <netipsec/ipsec_private.h> 92 #ifdef INET6 93 #include <netipsec/ipsec6.h> 94 #endif 95 #include <netipsec/ah_var.h> 96 #include <netipsec/esp_var.h> 97 #include <netipsec/ipcomp.h> /*XXX*/ 98 #include <netipsec/ipcomp_var.h> 99 100 #include <netipsec/key.h> 101 #include <netipsec/keydb.h> 102 #include <netipsec/key_debug.h> 103 104 #include <netipsec/xform.h> 105 106 #include <net/net_osdep.h> 107 108 int ipsec_used = 0; 109 int ipsec_enabled = 1; 110 111 #ifdef IPSEC_DEBUG 112 int ipsec_debug = 1; 113 114 /* 115 * When set to 1, IPsec will send packets with the same sequence number. 116 * This allows to verify if the other side has proper replay attacks detection. 117 */ 118 int ipsec_replay = 0; 119 120 /* 121 * When set 1, IPsec will send packets with corrupted HMAC. 122 * This allows to verify if the other side properly detects modified packets. 123 */ 124 int ipsec_integrity = 0; 125 #else 126 int ipsec_debug = 0; 127 #endif 128 129 percpu_t *ipsecstat_percpu; 130 int ip4_ah_offsetmask = 0; /* maybe IP_DF? */ 131 int ip4_ipsec_dfbit = 2; /* DF bit on encap. 0: clear 1: set 2: copy */ 132 int ip4_esp_trans_deflev = IPSEC_LEVEL_USE; 133 int ip4_esp_net_deflev = IPSEC_LEVEL_USE; 134 int ip4_ah_trans_deflev = IPSEC_LEVEL_USE; 135 int ip4_ah_net_deflev = IPSEC_LEVEL_USE; 136 struct secpolicy ip4_def_policy; 137 int ip4_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 138 int ip4_esp_randpad = -1; 139 140 u_int ipsec_spdgen = 1; /* SPD generation # */ 141 142 static struct secpolicy *ipsec_checkpcbcache (struct mbuf *, 143 struct inpcbpolicy *, int); 144 static int ipsec_fillpcbcache (struct inpcbpolicy *, struct mbuf *, 145 struct secpolicy *, int); 146 static int ipsec_invalpcbcache (struct inpcbpolicy *, int); 147 148 /* 149 * Crypto support requirements: 150 * 151 * 1 require hardware support 152 * -1 require software support 153 * 0 take anything 154 */ 155 int crypto_support = 0; 156 157 static struct secpolicy *ipsec_getpolicybysock(struct mbuf *, u_int, 158 struct inpcb_hdr *, int *); 159 160 #ifdef __FreeBSD__ 161 /* net.inet.ipsec */ 162 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_ESP_RANDPAD, 163 esp_randpad, CTLFLAG_RW, &ip4_esp_randpad, 0, ""); 164 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, 165 crypto_support, CTLFLAG_RW, &crypto_support,0, ""); 166 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_replay, CTLFLAG_RW, &ipsec_replay, 0, 167 "Emulate replay attack"); 168 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_integrity, CTLFLAG_RW, 169 &ipsec_integrity, 0, "Emulate man-in-the-middle attack"); 170 #endif /* __FreeBSD__ */ 171 172 #ifdef INET6 173 int ip6_esp_trans_deflev = IPSEC_LEVEL_USE; 174 int ip6_esp_net_deflev = IPSEC_LEVEL_USE; 175 int ip6_ah_trans_deflev = IPSEC_LEVEL_USE; 176 int ip6_ah_net_deflev = IPSEC_LEVEL_USE; 177 struct secpolicy ip6_def_policy; 178 int ip6_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 179 int ip6_esp_randpad = -1; 180 181 182 #ifdef __FreeBSD__ 183 /* net.inet6.ipsec6 */ 184 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_ESP_RANDPAD, 185 esp_randpad, CTLFLAG_RW, &ip6_esp_randpad, 0, ""); 186 #endif /* __FreeBSD__ */ 187 #endif /* INET6 */ 188 189 static int ipsec4_setspidx_inpcb (struct mbuf *, struct inpcb *); 190 #ifdef INET6 191 static int ipsec6_setspidx_in6pcb (struct mbuf *, struct in6pcb *); 192 #endif 193 static int ipsec_setspidx (struct mbuf *, struct secpolicyindex *, int); 194 static void ipsec4_get_ulp (struct mbuf *m, struct secpolicyindex *, int); 195 static int ipsec4_setspidx_ipaddr (struct mbuf *, struct secpolicyindex *); 196 #ifdef INET6 197 static void ipsec6_get_ulp (struct mbuf *m, struct secpolicyindex *, int); 198 static int ipsec6_setspidx_ipaddr (struct mbuf *, struct secpolicyindex *); 199 #endif 200 static void ipsec_delpcbpolicy (struct inpcbpolicy *); 201 #if 0 /* unused */ 202 static struct secpolicy *ipsec_deepcopy_policy (const struct secpolicy *); 203 #endif 204 static int ipsec_set_policy (struct secpolicy **, int, const void *, size_t, 205 kauth_cred_t); 206 static int ipsec_get_policy (struct secpolicy *, struct mbuf **); 207 static void ipsec_destroy_policy(struct secpolicy *); 208 static void vshiftl (unsigned char *, int, int); 209 static size_t ipsec_hdrsiz (const struct secpolicy *); 210 211 /* 212 * Try to validate and use cached policy on a PCB. 213 */ 214 static struct secpolicy * 215 ipsec_checkpcbcache(struct mbuf *m, struct inpcbpolicy *pcbsp, int dir) 216 { 217 struct secpolicyindex spidx; 218 struct secpolicy *sp = NULL; 219 int s; 220 221 KASSERT(IPSEC_DIR_IS_VALID(dir)); 222 KASSERT(pcbsp != NULL); 223 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 224 KASSERT(inph_locked(pcbsp->sp_inph)); 225 226 /* 227 * Checking the generation and sp->state and taking a reference to an SP 228 * must be in a critical section of pserialize. See key_unlink_sp. 229 */ 230 s = pserialize_read_enter(); 231 /* SPD table change invalidate all the caches. */ 232 if (ipsec_spdgen != pcbsp->sp_cache[dir].cachegen) { 233 ipsec_invalpcbcache(pcbsp, dir); 234 goto out; 235 } 236 sp = pcbsp->sp_cache[dir].cachesp; 237 if (sp == NULL) 238 goto out; 239 if (sp->state != IPSEC_SPSTATE_ALIVE) { 240 sp = NULL; 241 ipsec_invalpcbcache(pcbsp, dir); 242 goto out; 243 } 244 if ((pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) == 0) { 245 /* NB: assume ipsec_setspidx never sleep */ 246 if (ipsec_setspidx(m, &spidx, 1) != 0) { 247 sp = NULL; 248 goto out; 249 } 250 251 /* 252 * We have to make an exact match here since the cached rule 253 * might have lower priority than a rule that would otherwise 254 * have matched the packet. 255 */ 256 if (memcmp(&pcbsp->sp_cache[dir].cacheidx, &spidx, 257 sizeof(spidx))) { 258 sp = NULL; 259 goto out; 260 } 261 } else { 262 /* 263 * The pcb is connected, and the L4 code is sure that: 264 * - outgoing side uses inp_[lf]addr 265 * - incoming side looks up policy after inpcb lookup 266 * and address pair is know to be stable. We do not need 267 * to generate spidx again, nor check the address match again. 268 * 269 * For IPv4/v6 SOCK_STREAM sockets, this assumptions holds 270 * and there are calls to ipsec_pcbconn() from in_pcbconnect(). 271 */ 272 } 273 274 sp->lastused = time_second; 275 KEY_SP_REF(sp); 276 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 277 "DP cause refcnt++:%d SP:%p\n", 278 key_sp_refcnt(sp), pcbsp->sp_cache[dir].cachesp); 279 out: 280 pserialize_read_exit(s); 281 return sp; 282 } 283 284 static int 285 ipsec_fillpcbcache(struct inpcbpolicy *pcbsp, struct mbuf *m, 286 struct secpolicy *sp, int dir) 287 { 288 289 KASSERT(IPSEC_DIR_IS_INOROUT(dir)); 290 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 291 KASSERT(inph_locked(pcbsp->sp_inph)); 292 293 pcbsp->sp_cache[dir].cachesp = NULL; 294 pcbsp->sp_cache[dir].cachehint = IPSEC_PCBHINT_UNKNOWN; 295 if (ipsec_setspidx(m, &pcbsp->sp_cache[dir].cacheidx, 1) != 0) { 296 return EINVAL; 297 } 298 pcbsp->sp_cache[dir].cachesp = sp; 299 if (pcbsp->sp_cache[dir].cachesp) { 300 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 301 "DP cause refcnt++:%d SP:%p\n", 302 key_sp_refcnt(pcbsp->sp_cache[dir].cachesp), 303 pcbsp->sp_cache[dir].cachesp); 304 305 /* 306 * If the PCB is connected, we can remember a hint to 307 * possibly short-circuit IPsec processing in other places. 308 */ 309 if (pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) { 310 switch (pcbsp->sp_cache[dir].cachesp->policy) { 311 case IPSEC_POLICY_NONE: 312 case IPSEC_POLICY_BYPASS: 313 pcbsp->sp_cache[dir].cachehint = 314 IPSEC_PCBHINT_NO; 315 break; 316 default: 317 pcbsp->sp_cache[dir].cachehint = 318 IPSEC_PCBHINT_YES; 319 } 320 } 321 } 322 pcbsp->sp_cache[dir].cachegen = ipsec_spdgen; 323 324 return 0; 325 } 326 327 static int 328 ipsec_invalpcbcache(struct inpcbpolicy *pcbsp, int dir) 329 { 330 int i; 331 332 KASSERT(inph_locked(pcbsp->sp_inph)); 333 334 for (i = IPSEC_DIR_INBOUND; i <= IPSEC_DIR_OUTBOUND; i++) { 335 if (dir != IPSEC_DIR_ANY && i != dir) 336 continue; 337 pcbsp->sp_cache[i].cachesp = NULL; 338 pcbsp->sp_cache[i].cachehint = IPSEC_PCBHINT_UNKNOWN; 339 pcbsp->sp_cache[i].cachegen = 0; 340 memset(&pcbsp->sp_cache[i].cacheidx, 0, 341 sizeof(pcbsp->sp_cache[i].cacheidx)); 342 } 343 return 0; 344 } 345 346 void 347 ipsec_pcbconn(struct inpcbpolicy *pcbsp) 348 { 349 350 KASSERT(inph_locked(pcbsp->sp_inph)); 351 352 pcbsp->sp_cacheflags |= IPSEC_PCBSP_CONNECTED; 353 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 354 } 355 356 void 357 ipsec_pcbdisconn(struct inpcbpolicy *pcbsp) 358 { 359 360 KASSERT(inph_locked(pcbsp->sp_inph)); 361 362 pcbsp->sp_cacheflags &= ~IPSEC_PCBSP_CONNECTED; 363 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 364 } 365 366 void 367 ipsec_invalpcbcacheall(void) 368 { 369 370 if (ipsec_spdgen == UINT_MAX) 371 ipsec_spdgen = 1; 372 else 373 ipsec_spdgen++; 374 } 375 376 /* 377 * Return a held reference to the default SP. 378 */ 379 static struct secpolicy * 380 key_get_default_sp(int af, const char *where, int tag) 381 { 382 struct secpolicy *sp; 383 384 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP from %s:%u\n", where, tag); 385 386 switch(af) { 387 case AF_INET: 388 sp = &ip4_def_policy; 389 break; 390 #ifdef INET6 391 case AF_INET6: 392 sp = &ip6_def_policy; 393 break; 394 #endif 395 default: 396 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 397 "unexpected protocol family %u\n", af); 398 return NULL; 399 } 400 401 if (sp->policy != IPSEC_POLICY_DISCARD && 402 sp->policy != IPSEC_POLICY_NONE) { 403 IPSECLOG(LOG_INFO, "fixed system default policy: %d->%d\n", 404 sp->policy, IPSEC_POLICY_NONE); 405 sp->policy = IPSEC_POLICY_NONE; 406 } 407 KEY_SP_REF(sp); 408 409 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP returns SP:%p (%u)\n", 410 sp, key_sp_refcnt(sp)); 411 return sp; 412 } 413 #define KEY_GET_DEFAULT_SP(af) \ 414 key_get_default_sp((af), __func__, __LINE__) 415 416 /* 417 * For OUTBOUND packet having a socket. Searching SPD for packet, 418 * and return a pointer to SP. 419 * OUT: NULL: no apropreate SP found, the following value is set to error. 420 * 0 : bypass 421 * EACCES : discard packet. 422 * ENOENT : ipsec_acquire() in progress, maybe. 423 * others : error occurred. 424 * others: a pointer to SP 425 * 426 * NOTE: IPv6 mapped address concern is implemented here. 427 */ 428 static struct secpolicy * 429 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb_hdr *inph, 430 int *error) 431 { 432 struct inpcbpolicy *pcbsp = NULL; 433 struct secpolicy *currsp = NULL; /* policy on socket */ 434 struct secpolicy *sp; 435 int af; 436 437 KASSERT(m != NULL); 438 KASSERT(inph != NULL); 439 KASSERT(error != NULL); 440 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 441 442 KASSERT(inph->inph_socket != NULL); 443 KASSERT(inph_locked(inph)); 444 445 /* XXX FIXME inpcb/in6pcb vs socket*/ 446 af = inph->inph_af; 447 KASSERTMSG(af == AF_INET || af == AF_INET6, 448 "unexpected protocol family %u", af); 449 450 KASSERT(inph->inph_sp != NULL); 451 /* If we have a cached entry, and if it is still valid, use it. */ 452 IPSEC_STATINC(IPSEC_STAT_SPDCACHELOOKUP); 453 currsp = ipsec_checkpcbcache(m, inph->inph_sp, dir); 454 if (currsp) { 455 *error = 0; 456 return currsp; 457 } 458 IPSEC_STATINC(IPSEC_STAT_SPDCACHEMISS); 459 460 switch (af) { 461 case AF_INET: { 462 struct inpcb *in4p = (struct inpcb *)inph; 463 /* set spidx in pcb */ 464 *error = ipsec4_setspidx_inpcb(m, in4p); 465 pcbsp = in4p->inp_sp; 466 break; 467 } 468 469 #if defined(INET6) 470 case AF_INET6: { 471 struct in6pcb *in6p = (struct in6pcb *)inph; 472 /* set spidx in pcb */ 473 *error = ipsec6_setspidx_in6pcb(m, in6p); 474 pcbsp = in6p->in6p_sp; 475 break; 476 } 477 #endif 478 default: 479 *error = EPFNOSUPPORT; 480 break; 481 } 482 if (*error) 483 return NULL; 484 485 KASSERT(pcbsp != NULL); 486 switch (dir) { 487 case IPSEC_DIR_INBOUND: 488 currsp = pcbsp->sp_in; 489 break; 490 case IPSEC_DIR_OUTBOUND: 491 currsp = pcbsp->sp_out; 492 break; 493 } 494 KASSERT(currsp != NULL); 495 496 if (pcbsp->priv) { /* when privilieged socket */ 497 switch (currsp->policy) { 498 case IPSEC_POLICY_BYPASS: 499 case IPSEC_POLICY_IPSEC: 500 KEY_SP_REF(currsp); 501 sp = currsp; 502 break; 503 504 case IPSEC_POLICY_ENTRUST: 505 /* look for a policy in SPD */ 506 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 507 if (sp == NULL) /* no SP found */ 508 sp = KEY_GET_DEFAULT_SP(af); 509 break; 510 511 default: 512 IPSECLOG(LOG_ERR, "Invalid policy for PCB %d\n", 513 currsp->policy); 514 *error = EINVAL; 515 return NULL; 516 } 517 } else { /* unpriv, SPD has policy */ 518 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 519 if (sp == NULL) { /* no SP found */ 520 switch (currsp->policy) { 521 case IPSEC_POLICY_BYPASS: 522 IPSECLOG(LOG_ERR, "Illegal policy for " 523 "non-priviliged defined %d\n", 524 currsp->policy); 525 *error = EINVAL; 526 return NULL; 527 528 case IPSEC_POLICY_ENTRUST: 529 sp = KEY_GET_DEFAULT_SP(af); 530 break; 531 532 case IPSEC_POLICY_IPSEC: 533 KEY_SP_REF(currsp); 534 sp = currsp; 535 break; 536 537 default: 538 IPSECLOG(LOG_ERR, "Invalid policy for " 539 "PCB %d\n", currsp->policy); 540 *error = EINVAL; 541 return NULL; 542 } 543 } 544 } 545 KASSERTMSG(sp != NULL, "null SP (priv %u policy %u", pcbsp->priv, 546 currsp->policy); 547 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 548 "DP (priv %u policy %u) allocates SP:%p (refcnt %u)\n", 549 pcbsp->priv, currsp->policy, sp, key_sp_refcnt(sp)); 550 ipsec_fillpcbcache(pcbsp, m, sp, dir); 551 return sp; 552 } 553 554 /* 555 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 556 * and return a pointer to SP. 557 * OUT: positive: a pointer to the entry for security policy leaf matched. 558 * NULL: no apropreate SP found, the following value is set to error. 559 * 0 : bypass 560 * EACCES : discard packet. 561 * ENOENT : ipsec_acquire() in progress, maybe. 562 * others : error occurred. 563 */ 564 struct secpolicy * 565 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 566 { 567 struct secpolicyindex spidx; 568 struct secpolicy *sp; 569 570 KASSERT(m != NULL); 571 KASSERT(error != NULL); 572 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 573 574 sp = NULL; 575 576 /* Make an index to look for a policy. */ 577 *error = ipsec_setspidx(m, &spidx, (flag & IP_FORWARDING) ? 0 : 1); 578 if (*error != 0) { 579 IPSECLOG(LOG_DEBUG, "setpidx failed, dir %u flag %u\n", dir, flag); 580 memset(&spidx, 0, sizeof (spidx)); 581 return NULL; 582 } 583 584 spidx.dir = dir; 585 586 if (key_havesp(dir)) { 587 sp = KEY_LOOKUP_SP_BYSPIDX(&spidx, dir); 588 } 589 590 if (sp == NULL) /* no SP found, use system default */ 591 sp = KEY_GET_DEFAULT_SP(spidx.dst.sa.sa_family); 592 KASSERT(sp != NULL); 593 return sp; 594 } 595 596 struct secpolicy * 597 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 598 struct inpcb *inp) 599 { 600 struct secpolicy *sp; 601 602 *error = 0; 603 604 if (inp == NULL) { 605 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 606 } else { 607 KASSERT(inp->inp_socket != NULL); 608 sp = ipsec_getpolicybysock(m, dir, (struct inpcb_hdr *)inp, error); 609 } 610 if (sp == NULL) { 611 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 612 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 613 return NULL; 614 } 615 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 616 switch (sp->policy) { 617 case IPSEC_POLICY_ENTRUST: 618 default: 619 printf("%s: invalid policy %u\n", __func__, sp->policy); 620 /* fall thru... */ 621 case IPSEC_POLICY_DISCARD: 622 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 623 *error = -EINVAL; /* packet is discarded by caller */ 624 break; 625 case IPSEC_POLICY_BYPASS: 626 case IPSEC_POLICY_NONE: 627 KEY_SP_UNREF(&sp); 628 sp = NULL; /* NB: force NULL result */ 629 break; 630 case IPSEC_POLICY_IPSEC: 631 KASSERT(sp->req != NULL); 632 break; 633 } 634 if (*error != 0) { 635 KEY_SP_UNREF(&sp); 636 sp = NULL; 637 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 638 } 639 return sp; 640 } 641 642 int 643 ipsec4_output(struct mbuf *m, struct inpcb *inp, int flags, 644 u_long *mtu, bool *natt_frag, bool *done) 645 { 646 struct secpolicy *sp = NULL; 647 int error, s; 648 649 /* 650 * Check the security policy (SP) for the packet and, if required, 651 * do IPsec-related processing. There are two cases here; the first 652 * time a packet is sent through it will be untagged and handled by 653 * ipsec4_checkpolicy(). If the packet is resubmitted to ip_output 654 * (e.g. after AH, ESP, etc. processing), there will be a tag to 655 * bypass the lookup and related policy checking. 656 */ 657 if (ipsec_outdone(m)) { 658 return 0; 659 } 660 s = splsoftnet(); 661 if (inp && ipsec_pcb_skip_ipsec(inp->inp_sp, IPSEC_DIR_OUTBOUND)) { 662 splx(s); 663 return 0; 664 } 665 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, inp); 666 667 /* 668 * There are four return cases: 669 * sp != NULL apply IPsec policy 670 * sp == NULL, error == 0 no IPsec handling needed 671 * sp == NULL, error == -EINVAL discard packet w/o error 672 * sp == NULL, error != 0 discard packet, report error 673 */ 674 if (sp == NULL) { 675 splx(s); 676 if (error) { 677 /* 678 * Hack: -EINVAL is used to signal that a packet 679 * should be silently discarded. This is typically 680 * because we asked key management for an SA and 681 * it was delayed (e.g. kicked up to IKE). 682 */ 683 if (error == -EINVAL) 684 error = 0; 685 m_freem(m); 686 *done = true; 687 return error; 688 } 689 /* No IPsec processing for this packet. */ 690 return 0; 691 } 692 693 /* 694 * Do delayed checksums now because we send before 695 * this is done in the normal processing path. 696 */ 697 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 698 in_delayed_cksum(m); 699 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 700 } 701 702 { 703 u_long _mtu = 0; 704 705 /* Note: callee frees mbuf */ 706 error = ipsec4_process_packet(m, sp->req, &_mtu); 707 708 if (error == 0 && _mtu != 0) { 709 /* 710 * NAT-T ESP fragmentation: do not do IPSec processing 711 * now, we will do it on each fragmented packet. 712 */ 713 *mtu = _mtu; 714 *natt_frag = true; 715 KEY_SP_UNREF(&sp); 716 splx(s); 717 return 0; 718 } 719 } 720 /* 721 * Preserve KAME behaviour: ENOENT can be returned 722 * when an SA acquire is in progress. Don't propagate 723 * this to user-level; it confuses applications. 724 * 725 * XXX this will go away when the SADB is redone. 726 */ 727 if (error == ENOENT) 728 error = 0; 729 KEY_SP_UNREF(&sp); 730 splx(s); 731 *done = true; 732 return error; 733 } 734 735 int 736 ipsec4_input(struct mbuf *m, int flags) 737 { 738 struct secpolicy *sp; 739 int error, s; 740 741 s = splsoftnet(); 742 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 743 if (sp == NULL) { 744 splx(s); 745 return EINVAL; 746 } 747 748 /* 749 * Check security policy against packet attributes. 750 */ 751 error = ipsec_in_reject(sp, m); 752 KEY_SP_UNREF(&sp); 753 splx(s); 754 if (error) { 755 return error; 756 } 757 758 if (flags == 0) { 759 /* We are done. */ 760 return 0; 761 } 762 763 /* 764 * Peek at the outbound SP for this packet to determine if 765 * it is a Fast Forward candidate. 766 */ 767 s = splsoftnet(); 768 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, NULL); 769 if (sp != NULL) { 770 m->m_flags &= ~M_CANFASTFWD; 771 KEY_SP_UNREF(&sp); 772 } 773 splx(s); 774 return 0; 775 } 776 777 int 778 ipsec4_forward(struct mbuf *m, int *destmtu) 779 { 780 /* 781 * If the packet is routed over IPsec tunnel, tell the 782 * originator the tunnel MTU. 783 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 784 * XXX quickhack!!! 785 */ 786 struct secpolicy *sp; 787 size_t ipsechdr; 788 int error; 789 790 sp = ipsec4_getpolicybyaddr(m, 791 IPSEC_DIR_OUTBOUND, IP_FORWARDING, &error); 792 if (sp == NULL) { 793 return EINVAL; 794 } 795 796 /* Count IPsec header size. */ 797 ipsechdr = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, NULL); 798 799 /* 800 * Find the correct route for outer IPv4 header, compute tunnel MTU. 801 */ 802 if (sp->req) { 803 struct route *ro; 804 struct rtentry *rt; 805 struct secasvar *sav = NULL; 806 807 error = key_checkrequest(sp->req, &sav); 808 if (error != 0) 809 return error; 810 ro = &sav->sah->sa_route; 811 rt = rtcache_validate(ro); 812 if (rt && rt->rt_ifp) { 813 *destmtu = rt->rt_rmx.rmx_mtu ? 814 rt->rt_rmx.rmx_mtu : rt->rt_ifp->if_mtu; 815 *destmtu -= ipsechdr; 816 } 817 rtcache_unref(rt, ro); 818 KEY_SA_UNREF(&sav); 819 } 820 KEY_SP_UNREF(&sp); 821 return 0; 822 } 823 824 #ifdef INET6 825 struct secpolicy * 826 ipsec6_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 827 struct in6pcb *in6p) 828 { 829 struct secpolicy *sp; 830 831 *error = 0; 832 833 if (in6p == NULL) { 834 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 835 } else { 836 KASSERT(in6p->in6p_socket != NULL); 837 sp = ipsec_getpolicybysock(m, dir, (struct inpcb_hdr *)in6p, error); 838 } 839 if (sp == NULL) { 840 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 841 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 842 return NULL; 843 } 844 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 845 switch (sp->policy) { 846 case IPSEC_POLICY_ENTRUST: 847 default: 848 printf("%s: invalid policy %u\n", __func__, sp->policy); 849 /* fall thru... */ 850 case IPSEC_POLICY_DISCARD: 851 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 852 *error = -EINVAL; /* packet is discarded by caller */ 853 break; 854 case IPSEC_POLICY_BYPASS: 855 case IPSEC_POLICY_NONE: 856 KEY_SP_UNREF(&sp); 857 sp = NULL; /* NB: force NULL result */ 858 break; 859 case IPSEC_POLICY_IPSEC: 860 KASSERT(sp->req != NULL); 861 break; 862 } 863 if (*error != 0) { 864 KEY_SP_UNREF(&sp); 865 sp = NULL; 866 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 867 } 868 return sp; 869 } 870 #endif /* INET6 */ 871 872 static int 873 ipsec4_setspidx_inpcb(struct mbuf *m, struct inpcb *pcb) 874 { 875 int error; 876 877 KASSERT(pcb != NULL); 878 KASSERT(pcb->inp_sp != NULL); 879 KASSERT(pcb->inp_sp->sp_out != NULL); 880 KASSERT(pcb->inp_sp->sp_in != NULL); 881 882 error = ipsec_setspidx(m, &pcb->inp_sp->sp_in->spidx, 1); 883 if (error == 0) { 884 pcb->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 885 pcb->inp_sp->sp_out->spidx = pcb->inp_sp->sp_in->spidx; 886 pcb->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 887 } else { 888 memset(&pcb->inp_sp->sp_in->spidx, 0, 889 sizeof(pcb->inp_sp->sp_in->spidx)); 890 memset(&pcb->inp_sp->sp_out->spidx, 0, 891 sizeof(pcb->inp_sp->sp_in->spidx)); 892 } 893 return error; 894 } 895 896 #ifdef INET6 897 static int 898 ipsec6_setspidx_in6pcb(struct mbuf *m, struct in6pcb *pcb) 899 { 900 struct secpolicyindex *spidx; 901 int error; 902 903 KASSERT(pcb != NULL); 904 KASSERT(pcb->in6p_sp != NULL); 905 KASSERT(pcb->in6p_sp->sp_out != NULL); 906 KASSERT(pcb->in6p_sp->sp_in != NULL); 907 908 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 909 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 910 911 spidx = &pcb->in6p_sp->sp_in->spidx; 912 error = ipsec_setspidx(m, spidx, 1); 913 if (error) 914 goto bad; 915 spidx->dir = IPSEC_DIR_INBOUND; 916 917 spidx = &pcb->in6p_sp->sp_out->spidx; 918 error = ipsec_setspidx(m, spidx, 1); 919 if (error) 920 goto bad; 921 spidx->dir = IPSEC_DIR_OUTBOUND; 922 923 return 0; 924 925 bad: 926 memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx)); 927 memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx)); 928 return error; 929 } 930 #endif 931 932 /* 933 * configure security policy index (src/dst/proto/sport/dport) 934 * by looking at the content of mbuf. 935 * the caller is responsible for error recovery (like clearing up spidx). 936 */ 937 static int 938 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 939 { 940 struct ip *ip = NULL; 941 struct ip ipbuf; 942 u_int v; 943 struct mbuf *n; 944 int len; 945 int error; 946 947 KASSERT(m != NULL); 948 949 /* 950 * validate m->m_pkthdr.len. we see incorrect length if we 951 * mistakenly call this function with inconsistent mbuf chain 952 * (like 4.4BSD tcp/udp processing). XXX should we panic here? 953 */ 954 len = 0; 955 for (n = m; n; n = n->m_next) 956 len += n->m_len; 957 if (m->m_pkthdr.len != len) { 958 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 959 "total of m_len(%d) != pkthdr.len(%d), ignored.\n", 960 len, m->m_pkthdr.len); 961 return EINVAL; 962 } 963 964 if (m->m_pkthdr.len < sizeof(struct ip)) { 965 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 966 "pkthdr.len(%d) < sizeof(struct ip), ignored.\n", 967 m->m_pkthdr.len); 968 return EINVAL; 969 } 970 971 if (m->m_len >= sizeof(*ip)) 972 ip = mtod(m, struct ip *); 973 else { 974 m_copydata(m, 0, sizeof(ipbuf), &ipbuf); 975 ip = &ipbuf; 976 } 977 v = ip->ip_v; 978 switch (v) { 979 case 4: 980 error = ipsec4_setspidx_ipaddr(m, spidx); 981 if (error) 982 return error; 983 ipsec4_get_ulp(m, spidx, needport); 984 return 0; 985 #ifdef INET6 986 case 6: 987 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 988 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 989 "pkthdr.len(%d) < sizeof(struct ip6_hdr), " 990 "ignored.\n", m->m_pkthdr.len); 991 return EINVAL; 992 } 993 error = ipsec6_setspidx_ipaddr(m, spidx); 994 if (error) 995 return error; 996 ipsec6_get_ulp(m, spidx, needport); 997 return 0; 998 #endif 999 default: 1000 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1001 "unknown IP version %u, ignored.\n", v); 1002 return EINVAL; 1003 } 1004 } 1005 1006 static void 1007 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 1008 { 1009 u_int8_t nxt; 1010 int off; 1011 1012 /* sanity check */ 1013 KASSERT(m != NULL); 1014 KASSERTMSG(m->m_pkthdr.len >= sizeof(struct ip), "packet too short"); 1015 1016 /* NB: ip_input() flips it into host endian XXX need more checking */ 1017 if (m->m_len >= sizeof(struct ip)) { 1018 struct ip *ip = mtod(m, struct ip *); 1019 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 1020 goto done; 1021 off = ip->ip_hl << 2; 1022 nxt = ip->ip_p; 1023 } else { 1024 struct ip ih; 1025 1026 m_copydata(m, 0, sizeof (struct ip), &ih); 1027 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 1028 goto done; 1029 off = ih.ip_hl << 2; 1030 nxt = ih.ip_p; 1031 } 1032 1033 while (off < m->m_pkthdr.len) { 1034 struct ip6_ext ip6e; 1035 struct tcphdr th; 1036 struct udphdr uh; 1037 struct icmp icmph; 1038 1039 switch (nxt) { 1040 case IPPROTO_TCP: 1041 spidx->ul_proto = nxt; 1042 if (!needport) 1043 goto done_proto; 1044 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1045 goto done; 1046 m_copydata(m, off, sizeof (th), &th); 1047 spidx->src.sin.sin_port = th.th_sport; 1048 spidx->dst.sin.sin_port = th.th_dport; 1049 return; 1050 case IPPROTO_UDP: 1051 spidx->ul_proto = nxt; 1052 if (!needport) 1053 goto done_proto; 1054 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1055 goto done; 1056 m_copydata(m, off, sizeof (uh), &uh); 1057 spidx->src.sin.sin_port = uh.uh_sport; 1058 spidx->dst.sin.sin_port = uh.uh_dport; 1059 return; 1060 case IPPROTO_AH: 1061 if (m->m_pkthdr.len > off + sizeof(ip6e)) 1062 goto done; 1063 /* XXX sigh, this works but is totally bogus */ 1064 m_copydata(m, off, sizeof(ip6e), &ip6e); 1065 off += (ip6e.ip6e_len + 2) << 2; 1066 nxt = ip6e.ip6e_nxt; 1067 break; 1068 case IPPROTO_ICMP: 1069 spidx->ul_proto = nxt; 1070 if (off + sizeof(struct icmp) > m->m_pkthdr.len) 1071 return; 1072 m_copydata(m, off, sizeof(icmph), &icmph); 1073 ((struct sockaddr_in *)&spidx->src)->sin_port = 1074 htons((uint16_t)icmph.icmp_type); 1075 ((struct sockaddr_in *)&spidx->dst)->sin_port = 1076 htons((uint16_t)icmph.icmp_code); 1077 return; 1078 default: 1079 /* XXX intermediate headers??? */ 1080 spidx->ul_proto = nxt; 1081 goto done_proto; 1082 } 1083 } 1084 done: 1085 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1086 done_proto: 1087 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 1088 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 1089 } 1090 1091 /* assumes that m is sane */ 1092 static int 1093 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1094 { 1095 static const struct sockaddr_in template = { 1096 sizeof (struct sockaddr_in), 1097 AF_INET, 1098 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 1099 }; 1100 1101 spidx->src.sin = template; 1102 spidx->dst.sin = template; 1103 1104 if (m->m_len < sizeof (struct ip)) { 1105 m_copydata(m, offsetof(struct ip, ip_src), 1106 sizeof(struct in_addr), &spidx->src.sin.sin_addr); 1107 m_copydata(m, offsetof(struct ip, ip_dst), 1108 sizeof(struct in_addr), &spidx->dst.sin.sin_addr); 1109 } else { 1110 struct ip *ip = mtod(m, struct ip *); 1111 spidx->src.sin.sin_addr = ip->ip_src; 1112 spidx->dst.sin.sin_addr = ip->ip_dst; 1113 } 1114 1115 spidx->prefs = sizeof(struct in_addr) << 3; 1116 spidx->prefd = sizeof(struct in_addr) << 3; 1117 1118 return 0; 1119 } 1120 1121 #ifdef INET6 1122 static void 1123 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, 1124 int needport) 1125 { 1126 int off, nxt; 1127 struct tcphdr th; 1128 struct udphdr uh; 1129 struct icmp6_hdr icmph; 1130 1131 KASSERT(m != NULL); 1132 1133 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1134 printf("%s:\n", __func__); 1135 kdebug_mbuf(m); 1136 } 1137 1138 /* set default */ 1139 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1140 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 1141 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 1142 1143 nxt = -1; 1144 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 1145 if (off < 0 || m->m_pkthdr.len < off) 1146 return; 1147 1148 switch (nxt) { 1149 case IPPROTO_TCP: 1150 spidx->ul_proto = nxt; 1151 if (!needport) 1152 break; 1153 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1154 break; 1155 m_copydata(m, off, sizeof(th), &th); 1156 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 1157 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 1158 break; 1159 case IPPROTO_UDP: 1160 spidx->ul_proto = nxt; 1161 if (!needport) 1162 break; 1163 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1164 break; 1165 m_copydata(m, off, sizeof(uh), &uh); 1166 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 1167 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 1168 break; 1169 case IPPROTO_ICMPV6: 1170 spidx->ul_proto = nxt; 1171 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 1172 break; 1173 m_copydata(m, off, sizeof(icmph), &icmph); 1174 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 1175 htons((uint16_t)icmph.icmp6_type); 1176 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 1177 htons((uint16_t)icmph.icmp6_code); 1178 break; 1179 default: 1180 /* XXX intermediate headers??? */ 1181 spidx->ul_proto = nxt; 1182 break; 1183 } 1184 } 1185 1186 /* assumes that m is sane */ 1187 static int 1188 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1189 { 1190 struct ip6_hdr *ip6 = NULL; 1191 struct ip6_hdr ip6buf; 1192 struct sockaddr_in6 *sin6; 1193 1194 if (m->m_len >= sizeof(*ip6)) 1195 ip6 = mtod(m, struct ip6_hdr *); 1196 else { 1197 m_copydata(m, 0, sizeof(ip6buf), &ip6buf); 1198 ip6 = &ip6buf; 1199 } 1200 1201 sin6 = (struct sockaddr_in6 *)&spidx->src; 1202 memset(sin6, 0, sizeof(*sin6)); 1203 sin6->sin6_family = AF_INET6; 1204 sin6->sin6_len = sizeof(struct sockaddr_in6); 1205 memcpy(&sin6->sin6_addr, &ip6->ip6_src, sizeof(ip6->ip6_src)); 1206 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 1207 sin6->sin6_addr.s6_addr16[1] = 0; 1208 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 1209 } 1210 spidx->prefs = sizeof(struct in6_addr) << 3; 1211 1212 sin6 = (struct sockaddr_in6 *)&spidx->dst; 1213 memset(sin6, 0, sizeof(*sin6)); 1214 sin6->sin6_family = AF_INET6; 1215 sin6->sin6_len = sizeof(struct sockaddr_in6); 1216 memcpy(&sin6->sin6_addr, &ip6->ip6_dst, sizeof(ip6->ip6_dst)); 1217 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 1218 sin6->sin6_addr.s6_addr16[1] = 0; 1219 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 1220 } 1221 spidx->prefd = sizeof(struct in6_addr) << 3; 1222 1223 return 0; 1224 } 1225 #endif 1226 1227 static void 1228 ipsec_delpcbpolicy(struct inpcbpolicy *p) 1229 { 1230 1231 kmem_intr_free(p, sizeof(*p)); 1232 } 1233 1234 /* initialize policy in PCB */ 1235 int 1236 ipsec_init_policy(struct socket *so, struct inpcbpolicy **policy) 1237 { 1238 struct inpcbpolicy *new; 1239 1240 KASSERT(so != NULL); 1241 KASSERT(policy != NULL); 1242 1243 new = kmem_intr_zalloc(sizeof(*new), KM_NOSLEEP); 1244 if (new == NULL) { 1245 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1246 return ENOBUFS; 1247 } 1248 1249 if (IPSEC_PRIVILEGED_SO(so)) 1250 new->priv = 1; 1251 else 1252 new->priv = 0; 1253 1254 /* 1255 * These SPs are dummy. Never be used because the policy 1256 * is ENTRUST. See ipsec_getpolicybysock. 1257 */ 1258 new->sp_in = kmem_intr_zalloc(sizeof(struct secpolicy), KM_NOSLEEP); 1259 if (new->sp_in == NULL) { 1260 ipsec_delpcbpolicy(new); 1261 return ENOBUFS; 1262 } 1263 new->sp_in->state = IPSEC_SPSTATE_ALIVE; 1264 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 1265 new->sp_in->created = 0; /* Indicates dummy */ 1266 1267 new->sp_out = kmem_intr_zalloc(sizeof(struct secpolicy), KM_NOSLEEP); 1268 if (new->sp_out == NULL) { 1269 kmem_intr_free(new->sp_in, sizeof(struct secpolicy)); 1270 ipsec_delpcbpolicy(new); 1271 return ENOBUFS; 1272 } 1273 new->sp_out->state = IPSEC_SPSTATE_ALIVE; 1274 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 1275 new->sp_out->created = 0; /* Indicates dummy */ 1276 1277 *policy = new; 1278 1279 return 0; 1280 } 1281 1282 #if 0 /* unused */ 1283 /* copy old ipsec policy into new */ 1284 int 1285 ipsec_copy_policy(const struct inpcbpolicy *old, struct inpcbpolicy *new) 1286 { 1287 struct secpolicy *sp; 1288 1289 sp = ipsec_deepcopy_policy(old->sp_in); 1290 if (sp) { 1291 KEY_SP_UNREF(&new->sp_in); 1292 new->sp_in = sp; 1293 } else 1294 return ENOBUFS; 1295 1296 sp = ipsec_deepcopy_policy(old->sp_out); 1297 if (sp) { 1298 KEY_SP_UNREF(&new->sp_out); 1299 new->sp_out = sp; 1300 } else 1301 return ENOBUFS; 1302 1303 new->priv = old->priv; 1304 1305 return 0; 1306 } 1307 1308 /* deep-copy a policy in PCB */ 1309 static struct secpolicy * 1310 ipsec_deepcopy_policy(const struct secpolicy *src) 1311 { 1312 struct ipsecrequest *newchain = NULL; 1313 const struct ipsecrequest *p; 1314 struct ipsecrequest **q; 1315 struct secpolicy *dst; 1316 1317 if (src == NULL) 1318 return NULL; 1319 dst = KEY_NEWSP(); 1320 if (dst == NULL) 1321 return NULL; 1322 1323 /* 1324 * deep-copy IPsec request chain. This is required since struct 1325 * ipsecrequest is not reference counted. 1326 */ 1327 q = &newchain; 1328 for (p = src->req; p; p = p->next) { 1329 *q = kmem_zalloc(sizeof(**q), KM_SLEEP); 1330 (*q)->next = NULL; 1331 1332 (*q)->saidx.proto = p->saidx.proto; 1333 (*q)->saidx.mode = p->saidx.mode; 1334 (*q)->level = p->level; 1335 (*q)->saidx.reqid = p->saidx.reqid; 1336 1337 memcpy(&(*q)->saidx.src, &p->saidx.src, sizeof((*q)->saidx.src)); 1338 memcpy(&(*q)->saidx.dst, &p->saidx.dst, sizeof((*q)->saidx.dst)); 1339 1340 (*q)->sp = dst; 1341 1342 q = &((*q)->next); 1343 } 1344 1345 dst->req = newchain; 1346 dst->state = src->state; 1347 dst->policy = src->policy; 1348 /* do not touch the refcnt fields */ 1349 1350 return dst; 1351 } 1352 #endif 1353 1354 static void 1355 ipsec_destroy_policy(struct secpolicy *sp) 1356 { 1357 1358 if (sp->created == 0) 1359 /* It's dummy. We can simply free it */ 1360 kmem_intr_free(sp, sizeof(*sp)); 1361 else { 1362 /* 1363 * We cannot destroy here because it can be called in 1364 * softint. So mark the SP as DEAD and let the timer 1365 * destroy it. See key_timehandler_spd. 1366 */ 1367 sp->state = IPSEC_SPSTATE_DEAD; 1368 } 1369 } 1370 1371 /* set policy and ipsec request if present. */ 1372 static int 1373 ipsec_set_policy( 1374 struct secpolicy **policy, 1375 int optname, 1376 const void *request, 1377 size_t len, 1378 kauth_cred_t cred 1379 ) 1380 { 1381 const struct sadb_x_policy *xpl; 1382 struct secpolicy *newsp = NULL, *oldsp; 1383 int error; 1384 1385 KASSERT(!cpu_softintr_p()); 1386 1387 /* sanity check. */ 1388 if (policy == NULL || *policy == NULL || request == NULL) 1389 return EINVAL; 1390 if (len < sizeof(*xpl)) 1391 return EINVAL; 1392 xpl = (const struct sadb_x_policy *)request; 1393 1394 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1395 printf("%s: passed policy\n", __func__); 1396 kdebug_sadb_x_policy((const struct sadb_ext *)xpl); 1397 } 1398 1399 /* check policy type */ 1400 /* ipsec_set_policy() accepts IPSEC, ENTRUST and BYPASS. */ 1401 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 1402 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1403 return EINVAL; 1404 1405 /* check privileged socket */ 1406 if (xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1407 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPSEC, 1408 KAUTH_REQ_NETWORK_IPSEC_BYPASS, NULL, NULL, NULL); 1409 if (error) 1410 return (error); 1411 } 1412 1413 /* allocation new SP entry */ 1414 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1415 return error; 1416 1417 key_init_sp(newsp); 1418 newsp->created = time_uptime; 1419 /* Insert the global list for SPs for sockets */ 1420 key_socksplist_add(newsp); 1421 1422 /* clear old SP and set new SP */ 1423 oldsp = *policy; 1424 *policy = newsp; 1425 ipsec_destroy_policy(oldsp); 1426 1427 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1428 printf("%s: new policy\n", __func__); 1429 kdebug_secpolicy(newsp); 1430 } 1431 1432 return 0; 1433 } 1434 1435 static int 1436 ipsec_get_policy(struct secpolicy *policy, struct mbuf **mp) 1437 { 1438 1439 /* sanity check. */ 1440 if (policy == NULL || mp == NULL) 1441 return EINVAL; 1442 1443 *mp = key_sp2msg(policy); 1444 if (!*mp) { 1445 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1446 return ENOBUFS; 1447 } 1448 1449 (*mp)->m_type = MT_DATA; 1450 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1451 printf("%s:\n", __func__); 1452 kdebug_mbuf(*mp); 1453 } 1454 1455 return 0; 1456 } 1457 1458 int 1459 ipsec4_set_policy(struct inpcb *inp, int optname, const void *request, 1460 size_t len, kauth_cred_t cred) 1461 { 1462 const struct sadb_x_policy *xpl; 1463 struct secpolicy **policy; 1464 1465 KASSERT(!cpu_softintr_p()); 1466 KASSERT(inp_locked(inp)); 1467 1468 /* sanity check. */ 1469 if (inp == NULL || request == NULL) 1470 return EINVAL; 1471 if (len < sizeof(*xpl)) 1472 return EINVAL; 1473 xpl = (const struct sadb_x_policy *)request; 1474 1475 KASSERT(inp->inp_sp != NULL); 1476 1477 /* select direction */ 1478 switch (xpl->sadb_x_policy_dir) { 1479 case IPSEC_DIR_INBOUND: 1480 policy = &inp->inp_sp->sp_in; 1481 break; 1482 case IPSEC_DIR_OUTBOUND: 1483 policy = &inp->inp_sp->sp_out; 1484 break; 1485 default: 1486 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1487 xpl->sadb_x_policy_dir); 1488 return EINVAL; 1489 } 1490 1491 return ipsec_set_policy(policy, optname, request, len, cred); 1492 } 1493 1494 int 1495 ipsec4_get_policy(struct inpcb *inp, const void *request, size_t len, 1496 struct mbuf **mp) 1497 { 1498 const struct sadb_x_policy *xpl; 1499 struct secpolicy *policy; 1500 1501 /* sanity check. */ 1502 if (inp == NULL || request == NULL || mp == NULL) 1503 return EINVAL; 1504 KASSERT(inp->inp_sp != NULL); 1505 if (len < sizeof(*xpl)) 1506 return EINVAL; 1507 xpl = (const struct sadb_x_policy *)request; 1508 1509 /* select direction */ 1510 switch (xpl->sadb_x_policy_dir) { 1511 case IPSEC_DIR_INBOUND: 1512 policy = inp->inp_sp->sp_in; 1513 break; 1514 case IPSEC_DIR_OUTBOUND: 1515 policy = inp->inp_sp->sp_out; 1516 break; 1517 default: 1518 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1519 xpl->sadb_x_policy_dir); 1520 return EINVAL; 1521 } 1522 1523 return ipsec_get_policy(policy, mp); 1524 } 1525 1526 /* delete policy in PCB */ 1527 int 1528 ipsec4_delete_pcbpolicy(struct inpcb *inp) 1529 { 1530 1531 KASSERT(inp != NULL); 1532 1533 if (inp->inp_sp == NULL) 1534 return 0; 1535 1536 if (inp->inp_sp->sp_in != NULL) 1537 ipsec_destroy_policy(inp->inp_sp->sp_in); 1538 1539 if (inp->inp_sp->sp_out != NULL) 1540 ipsec_destroy_policy(inp->inp_sp->sp_out); 1541 1542 ipsec_invalpcbcache(inp->inp_sp, IPSEC_DIR_ANY); 1543 1544 ipsec_delpcbpolicy(inp->inp_sp); 1545 inp->inp_sp = NULL; 1546 1547 return 0; 1548 } 1549 1550 #ifdef INET6 1551 int 1552 ipsec6_set_policy(struct in6pcb *in6p, int optname, const void *request, 1553 size_t len, kauth_cred_t cred) 1554 { 1555 const struct sadb_x_policy *xpl; 1556 struct secpolicy **policy; 1557 1558 KASSERT(!cpu_softintr_p()); 1559 KASSERT(in6p_locked(in6p)); 1560 1561 /* sanity check. */ 1562 if (in6p == NULL || request == NULL) 1563 return EINVAL; 1564 if (len < sizeof(*xpl)) 1565 return EINVAL; 1566 xpl = (const struct sadb_x_policy *)request; 1567 1568 /* select direction */ 1569 switch (xpl->sadb_x_policy_dir) { 1570 case IPSEC_DIR_INBOUND: 1571 policy = &in6p->in6p_sp->sp_in; 1572 break; 1573 case IPSEC_DIR_OUTBOUND: 1574 policy = &in6p->in6p_sp->sp_out; 1575 break; 1576 default: 1577 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1578 xpl->sadb_x_policy_dir); 1579 return EINVAL; 1580 } 1581 1582 return ipsec_set_policy(policy, optname, request, len, cred); 1583 } 1584 1585 int 1586 ipsec6_get_policy(struct in6pcb *in6p, const void *request, size_t len, 1587 struct mbuf **mp) 1588 { 1589 const struct sadb_x_policy *xpl; 1590 struct secpolicy *policy; 1591 1592 /* sanity check. */ 1593 if (in6p == NULL || request == NULL || mp == NULL) 1594 return EINVAL; 1595 KASSERT(in6p->in6p_sp != NULL); 1596 if (len < sizeof(*xpl)) 1597 return EINVAL; 1598 xpl = (const struct sadb_x_policy *)request; 1599 1600 /* select direction */ 1601 switch (xpl->sadb_x_policy_dir) { 1602 case IPSEC_DIR_INBOUND: 1603 policy = in6p->in6p_sp->sp_in; 1604 break; 1605 case IPSEC_DIR_OUTBOUND: 1606 policy = in6p->in6p_sp->sp_out; 1607 break; 1608 default: 1609 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1610 xpl->sadb_x_policy_dir); 1611 return EINVAL; 1612 } 1613 1614 return ipsec_get_policy(policy, mp); 1615 } 1616 1617 int 1618 ipsec6_delete_pcbpolicy(struct in6pcb *in6p) 1619 { 1620 1621 KASSERT(in6p != NULL); 1622 1623 if (in6p->in6p_sp == NULL) 1624 return 0; 1625 1626 if (in6p->in6p_sp->sp_in != NULL) 1627 ipsec_destroy_policy(in6p->in6p_sp->sp_in); 1628 1629 if (in6p->in6p_sp->sp_out != NULL) 1630 ipsec_destroy_policy(in6p->in6p_sp->sp_out); 1631 1632 ipsec_invalpcbcache(in6p->in6p_sp, IPSEC_DIR_ANY); 1633 1634 ipsec_delpcbpolicy(in6p->in6p_sp); 1635 in6p->in6p_sp = NULL; 1636 1637 return 0; 1638 } 1639 #endif 1640 1641 /* 1642 * return current level. 1643 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1644 */ 1645 u_int 1646 ipsec_get_reqlevel(const struct ipsecrequest *isr) 1647 { 1648 u_int level = 0; 1649 u_int esp_trans_deflev, esp_net_deflev; 1650 u_int ah_trans_deflev, ah_net_deflev; 1651 1652 KASSERT(isr != NULL); 1653 KASSERT(isr->sp != NULL); 1654 KASSERTMSG( 1655 isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1656 "af family mismatch, src %u, dst %u", 1657 isr->sp->spidx.src.sa.sa_family, isr->sp->spidx.dst.sa.sa_family); 1658 1659 /* XXX note that we have ipseclog() expanded here - code sync issue */ 1660 #define IPSEC_CHECK_DEFAULT(lev) \ 1661 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1662 && (lev) != IPSEC_LEVEL_UNIQUE) ? \ 1663 (ipsec_debug ? log(LOG_INFO, "fixed system default level " #lev \ 1664 ":%d->%d\n", (lev), IPSEC_LEVEL_REQUIRE) : (void)0), \ 1665 (lev) = IPSEC_LEVEL_REQUIRE, (lev) \ 1666 : (lev)) 1667 1668 /* set default level */ 1669 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1670 #ifdef INET 1671 case AF_INET: 1672 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_trans_deflev); 1673 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_net_deflev); 1674 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_trans_deflev); 1675 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_net_deflev); 1676 break; 1677 #endif 1678 #ifdef INET6 1679 case AF_INET6: 1680 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_trans_deflev); 1681 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_net_deflev); 1682 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_trans_deflev); 1683 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_net_deflev); 1684 break; 1685 #endif /* INET6 */ 1686 default: 1687 panic("%s: unknown af %u", __func__, 1688 isr->sp->spidx.src.sa.sa_family); 1689 } 1690 1691 #undef IPSEC_CHECK_DEFAULT 1692 1693 /* set level */ 1694 switch (isr->level) { 1695 case IPSEC_LEVEL_DEFAULT: 1696 switch (isr->saidx.proto) { 1697 case IPPROTO_ESP: 1698 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1699 level = esp_net_deflev; 1700 else 1701 level = esp_trans_deflev; 1702 break; 1703 case IPPROTO_AH: 1704 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1705 level = ah_net_deflev; 1706 else 1707 level = ah_trans_deflev; 1708 break; 1709 case IPPROTO_IPCOMP: 1710 /* 1711 * we don't really care, as IPcomp document says that 1712 * we shouldn't compress small packets 1713 */ 1714 level = IPSEC_LEVEL_USE; 1715 break; 1716 default: 1717 panic("%s: Illegal protocol defined %u", __func__, 1718 isr->saidx.proto); 1719 } 1720 break; 1721 1722 case IPSEC_LEVEL_USE: 1723 case IPSEC_LEVEL_REQUIRE: 1724 level = isr->level; 1725 break; 1726 case IPSEC_LEVEL_UNIQUE: 1727 level = IPSEC_LEVEL_REQUIRE; 1728 break; 1729 1730 default: 1731 panic("%s: Illegal IPsec level %u", __func__, isr->level); 1732 } 1733 1734 return level; 1735 } 1736 1737 /* 1738 * Check security policy requirements against the actual 1739 * packet contents. Return one if the packet should be 1740 * reject as "invalid"; otherwiser return zero to have the 1741 * packet treated as "valid". 1742 * 1743 * OUT: 1744 * 0: valid 1745 * 1: invalid 1746 */ 1747 int 1748 ipsec_in_reject(const struct secpolicy *sp, const struct mbuf *m) 1749 { 1750 struct ipsecrequest *isr; 1751 1752 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1753 printf("%s: using SP\n", __func__); 1754 kdebug_secpolicy(sp); 1755 } 1756 1757 /* check policy */ 1758 switch (sp->policy) { 1759 case IPSEC_POLICY_DISCARD: 1760 return 1; 1761 case IPSEC_POLICY_BYPASS: 1762 case IPSEC_POLICY_NONE: 1763 return 0; 1764 } 1765 1766 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1767 "invalid policy %u", sp->policy); 1768 1769 /* XXX should compare policy against ipsec header history */ 1770 1771 for (isr = sp->req; isr != NULL; isr = isr->next) { 1772 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1773 continue; 1774 switch (isr->saidx.proto) { 1775 case IPPROTO_ESP: 1776 if ((m->m_flags & M_DECRYPTED) == 0) { 1777 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1778 "ESP m_flags:%x\n", m->m_flags); 1779 return 1; 1780 } 1781 break; 1782 case IPPROTO_AH: 1783 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1784 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1785 "AH m_flags:%x\n", m->m_flags); 1786 return 1; 1787 } 1788 break; 1789 case IPPROTO_IPCOMP: 1790 /* 1791 * we don't really care, as IPcomp document 1792 * says that we shouldn't compress small 1793 * packets, IPComp policy should always be 1794 * treated as being in "use" level. 1795 */ 1796 break; 1797 } 1798 } 1799 return 0; /* valid */ 1800 } 1801 1802 /* 1803 * Check AH/ESP integrity. 1804 * This function is called from tcp_input(), udp_input(), 1805 * and {ah,esp}4_input for tunnel mode 1806 */ 1807 int 1808 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1809 { 1810 struct secpolicy *sp; 1811 int error; 1812 int result; 1813 1814 KASSERT(m != NULL); 1815 1816 /* get SP for this packet. 1817 * When we are called from ip_forward(), we call 1818 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1819 */ 1820 if (inp == NULL) 1821 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1822 else 1823 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1824 (struct inpcb_hdr *)inp, &error); 1825 1826 if (sp != NULL) { 1827 result = ipsec_in_reject(sp, m); 1828 if (result) 1829 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1830 KEY_SP_UNREF(&sp); 1831 } else { 1832 result = 0; /* XXX should be panic ? 1833 * -> No, there may be error. */ 1834 } 1835 return result; 1836 } 1837 1838 1839 #ifdef INET6 1840 /* 1841 * Check AH/ESP integrity. 1842 * This function is called from tcp6_input(), udp6_input(), 1843 * and {ah,esp}6_input for tunnel mode 1844 */ 1845 int 1846 ipsec6_in_reject(struct mbuf *m, struct in6pcb *in6p) 1847 { 1848 struct secpolicy *sp = NULL; 1849 int error; 1850 int result; 1851 1852 KASSERT(m != NULL); 1853 1854 /* get SP for this packet. 1855 * When we are called from ip_forward(), we call 1856 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1857 */ 1858 if (in6p == NULL) 1859 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1860 else 1861 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1862 (struct inpcb_hdr *)in6p, 1863 &error); 1864 1865 if (sp != NULL) { 1866 result = ipsec_in_reject(sp, m); 1867 if (result) 1868 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1869 KEY_SP_UNREF(&sp); 1870 } else { 1871 result = 0; 1872 } 1873 return result; 1874 } 1875 #endif 1876 1877 /* 1878 * compute the byte size to be occupied by IPsec header. 1879 * in case it is tunneled, it includes the size of outer IP header. 1880 * NOTE: SP passed is free in this function. 1881 */ 1882 static size_t 1883 ipsec_hdrsiz(const struct secpolicy *sp) 1884 { 1885 struct ipsecrequest *isr; 1886 size_t siz; 1887 1888 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1889 printf("%s: using SP\n", __func__); 1890 kdebug_secpolicy(sp); 1891 } 1892 1893 switch (sp->policy) { 1894 case IPSEC_POLICY_DISCARD: 1895 case IPSEC_POLICY_BYPASS: 1896 case IPSEC_POLICY_NONE: 1897 return 0; 1898 } 1899 1900 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1901 "invalid policy %u", sp->policy); 1902 1903 siz = 0; 1904 for (isr = sp->req; isr != NULL; isr = isr->next) { 1905 size_t clen = 0; 1906 struct secasvar *sav = NULL; 1907 int error; 1908 1909 switch (isr->saidx.proto) { 1910 case IPPROTO_ESP: 1911 error = key_checkrequest(isr, &sav); 1912 if (error == 0) { 1913 clen = esp_hdrsiz(sav); 1914 KEY_SA_UNREF(&sav); 1915 } else 1916 clen = esp_hdrsiz(NULL); 1917 break; 1918 case IPPROTO_AH: 1919 error = key_checkrequest(isr, &sav); 1920 if (error == 0) { 1921 clen = ah_hdrsiz(sav); 1922 KEY_SA_UNREF(&sav); 1923 } else 1924 clen = ah_hdrsiz(NULL); 1925 break; 1926 case IPPROTO_IPCOMP: 1927 clen = sizeof(struct ipcomp); 1928 break; 1929 } 1930 1931 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1932 switch (isr->saidx.dst.sa.sa_family) { 1933 case AF_INET: 1934 clen += sizeof(struct ip); 1935 break; 1936 #ifdef INET6 1937 case AF_INET6: 1938 clen += sizeof(struct ip6_hdr); 1939 break; 1940 #endif 1941 default: 1942 IPSECLOG(LOG_ERR, "unknown AF %d in " 1943 "IPsec tunnel SA\n", 1944 ((const struct sockaddr *)&isr->saidx.dst) 1945 ->sa_family); 1946 break; 1947 } 1948 } 1949 siz += clen; 1950 } 1951 1952 return siz; 1953 } 1954 1955 /* This function is called from ip_forward() and ipsec4_hdrsize_tcp(). */ 1956 size_t 1957 ipsec4_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1958 { 1959 struct secpolicy *sp; 1960 int error; 1961 size_t size; 1962 1963 KASSERT(m != NULL); 1964 KASSERTMSG(inp == NULL || inp->inp_socket != NULL, "socket w/o inpcb"); 1965 1966 /* get SP for this packet. 1967 * When we are called from ip_forward(), we call 1968 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1969 */ 1970 if (inp == NULL) 1971 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1972 else 1973 sp = ipsec_getpolicybysock(m, dir, 1974 (struct inpcb_hdr *)inp, &error); 1975 1976 if (sp != NULL) { 1977 size = ipsec_hdrsiz(sp); 1978 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%lu.\n", 1979 (unsigned long)size); 1980 1981 KEY_SP_UNREF(&sp); 1982 } else { 1983 size = 0; /* XXX should be panic ? */ 1984 } 1985 return size; 1986 } 1987 1988 #ifdef INET6 1989 /* This function is called from ipsec6_hdrsize_tcp(), 1990 * and maybe from ip6_forward.() 1991 */ 1992 size_t 1993 ipsec6_hdrsiz(struct mbuf *m, u_int dir, struct in6pcb *in6p) 1994 { 1995 struct secpolicy *sp; 1996 int error; 1997 size_t size; 1998 1999 KASSERT(m != NULL); 2000 KASSERTMSG(in6p == NULL || in6p->in6p_socket != NULL, 2001 "socket w/o inpcb"); 2002 2003 /* get SP for this packet */ 2004 /* XXX Is it right to call with IP_FORWARDING. */ 2005 if (in6p == NULL) 2006 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 2007 else 2008 sp = ipsec_getpolicybysock(m, dir, 2009 (struct inpcb_hdr *)in6p, 2010 &error); 2011 2012 if (sp == NULL) 2013 return 0; 2014 size = ipsec_hdrsiz(sp); 2015 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%zu.\n", size); 2016 KEY_SP_UNREF(&sp); 2017 2018 return size; 2019 } 2020 #endif /*INET6*/ 2021 2022 /* 2023 * Check the variable replay window. 2024 * ipsec_chkreplay() performs replay check before ICV verification. 2025 * ipsec_updatereplay() updates replay bitmap. This must be called after 2026 * ICV verification (it also performs replay check, which is usually done 2027 * beforehand). 2028 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 2029 * 2030 * based on RFC 2401. 2031 */ 2032 int 2033 ipsec_chkreplay(u_int32_t seq, const struct secasvar *sav) 2034 { 2035 const struct secreplay *replay; 2036 u_int32_t diff; 2037 int fr; 2038 u_int32_t wsizeb; /* constant: bits of window size */ 2039 int frlast; /* constant: last frame */ 2040 2041 IPSEC_SPLASSERT_SOFTNET(__func__); 2042 2043 KASSERT(sav != NULL); 2044 KASSERT(sav->replay != NULL); 2045 2046 replay = sav->replay; 2047 2048 if (replay->wsize == 0) 2049 return 1; /* no need to check replay. */ 2050 2051 /* constant */ 2052 frlast = replay->wsize - 1; 2053 wsizeb = replay->wsize << 3; 2054 2055 /* sequence number of 0 is invalid */ 2056 if (seq == 0) 2057 return 0; 2058 2059 /* first time is always okay */ 2060 if (replay->count == 0) 2061 return 1; 2062 2063 if (seq > replay->lastseq) { 2064 /* larger sequences are okay */ 2065 return 1; 2066 } else { 2067 /* seq is equal or less than lastseq. */ 2068 diff = replay->lastseq - seq; 2069 2070 /* over range to check, i.e. too old or wrapped */ 2071 if (diff >= wsizeb) 2072 return 0; 2073 2074 fr = frlast - diff / 8; 2075 2076 /* this packet already seen ? */ 2077 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2078 return 0; 2079 2080 /* out of order but good */ 2081 return 1; 2082 } 2083 } 2084 2085 /* 2086 * check replay counter whether to update or not. 2087 * OUT: 0: OK 2088 * 1: NG 2089 */ 2090 int 2091 ipsec_updatereplay(u_int32_t seq, const struct secasvar *sav) 2092 { 2093 struct secreplay *replay; 2094 u_int32_t diff; 2095 int fr; 2096 u_int32_t wsizeb; /* constant: bits of window size */ 2097 int frlast; /* constant: last frame */ 2098 char buf[INET6_ADDRSTRLEN]; 2099 2100 IPSEC_SPLASSERT_SOFTNET(__func__); 2101 2102 KASSERT(sav != NULL); 2103 KASSERT(sav->replay != NULL); 2104 2105 replay = sav->replay; 2106 2107 if (replay->wsize == 0) 2108 goto ok; /* no need to check replay. */ 2109 2110 /* constant */ 2111 frlast = replay->wsize - 1; 2112 wsizeb = replay->wsize << 3; 2113 2114 /* sequence number of 0 is invalid */ 2115 if (seq == 0) 2116 return 1; 2117 2118 /* first time */ 2119 if (replay->count == 0) { 2120 replay->lastseq = seq; 2121 memset(replay->bitmap, 0, replay->wsize); 2122 (replay->bitmap)[frlast] = 1; 2123 goto ok; 2124 } 2125 2126 if (seq > replay->lastseq) { 2127 /* seq is larger than lastseq. */ 2128 diff = seq - replay->lastseq; 2129 2130 /* new larger sequence number */ 2131 if (diff < wsizeb) { 2132 /* In window */ 2133 /* set bit for this packet */ 2134 vshiftl(replay->bitmap, diff, replay->wsize); 2135 (replay->bitmap)[frlast] |= 1; 2136 } else { 2137 /* this packet has a "way larger" */ 2138 memset(replay->bitmap, 0, replay->wsize); 2139 (replay->bitmap)[frlast] = 1; 2140 } 2141 replay->lastseq = seq; 2142 2143 /* larger is good */ 2144 } else { 2145 /* seq is equal or less than lastseq. */ 2146 diff = replay->lastseq - seq; 2147 2148 /* over range to check, i.e. too old or wrapped */ 2149 if (diff >= wsizeb) 2150 return 1; 2151 2152 fr = frlast - diff / 8; 2153 2154 /* this packet already seen ? */ 2155 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2156 return 1; 2157 2158 /* mark as seen */ 2159 (replay->bitmap)[fr] |= (1 << (diff % 8)); 2160 2161 /* out of order but good */ 2162 } 2163 2164 ok: 2165 if (replay->count == ~0) { 2166 2167 /* set overflow flag */ 2168 replay->overflow++; 2169 2170 /* don't increment, no more packets accepted */ 2171 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 2172 return 1; 2173 2174 IPSECLOG(LOG_WARNING, "replay counter made %d cycle. %s\n", 2175 replay->overflow, ipsec_logsastr(sav, buf, sizeof(buf))); 2176 } 2177 2178 replay->count++; 2179 2180 return 0; 2181 } 2182 2183 /* 2184 * shift variable length bunffer to left. 2185 * IN: bitmap: pointer to the buffer 2186 * nbit: the number of to shift. 2187 * wsize: buffer size (bytes). 2188 */ 2189 static void 2190 vshiftl(unsigned char *bitmap, int nbit, int wsize) 2191 { 2192 int s, j, i; 2193 unsigned char over; 2194 2195 for (j = 0; j < nbit; j += 8) { 2196 s = (nbit - j < 8) ? (nbit - j): 8; 2197 bitmap[0] <<= s; 2198 for (i = 1; i < wsize; i++) { 2199 over = (bitmap[i] >> (8 - s)); 2200 bitmap[i] <<= s; 2201 bitmap[i-1] |= over; 2202 } 2203 } 2204 2205 return; 2206 } 2207 2208 /* Return a printable string for the address. */ 2209 const char * 2210 ipsec_address(const union sockaddr_union *sa, char *buf, size_t size) 2211 { 2212 switch (sa->sa.sa_family) { 2213 #if INET 2214 case AF_INET: 2215 in_print(buf, size, &sa->sin.sin_addr); 2216 return buf; 2217 #endif /* INET */ 2218 2219 #if INET6 2220 case AF_INET6: 2221 in6_print(buf, size, &sa->sin6.sin6_addr); 2222 return buf; 2223 #endif /* INET6 */ 2224 2225 default: 2226 return "(unknown address family)"; 2227 } 2228 } 2229 2230 const char * 2231 ipsec_logsastr(const struct secasvar *sav, char *buf, size_t size) 2232 { 2233 const struct secasindex *saidx = &sav->sah->saidx; 2234 char sbuf[IPSEC_ADDRSTRLEN], dbuf[IPSEC_ADDRSTRLEN]; 2235 2236 KASSERTMSG(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 2237 "af family mismatch, src %u, dst %u", 2238 saidx->src.sa.sa_family, saidx->dst.sa.sa_family); 2239 2240 snprintf(buf, size, "SA(SPI=%u src=%s dst=%s)", 2241 (u_int32_t)ntohl(sav->spi), 2242 ipsec_address(&saidx->src, sbuf, sizeof(sbuf)), 2243 ipsec_address(&saidx->dst, dbuf, sizeof(dbuf))); 2244 2245 return buf; 2246 } 2247 2248 void 2249 ipsec_dumpmbuf(struct mbuf *m) 2250 { 2251 int totlen; 2252 int i; 2253 u_char *p; 2254 2255 totlen = 0; 2256 printf("---\n"); 2257 while (m) { 2258 p = mtod(m, u_char *); 2259 for (i = 0; i < m->m_len; i++) { 2260 printf("%02x ", p[i]); 2261 totlen++; 2262 if (totlen % 16 == 0) 2263 printf("\n"); 2264 } 2265 m = m->m_next; 2266 } 2267 if (totlen % 16 != 0) 2268 printf("\n"); 2269 printf("---\n"); 2270 } 2271 2272 #ifdef INET6 2273 struct secpolicy * 2274 ipsec6_check_policy(struct mbuf *m, struct in6pcb *in6p, 2275 int flags, int *needipsecp, int *errorp) 2276 { 2277 struct secpolicy *sp = NULL; 2278 int s; 2279 int error = 0; 2280 int needipsec = 0; 2281 2282 if (!ipsec_outdone(m)) { 2283 s = splsoftnet(); 2284 if (in6p != NULL && 2285 ipsec_pcb_skip_ipsec(in6p->in6p_sp, IPSEC_DIR_OUTBOUND)) { 2286 splx(s); 2287 goto skippolicycheck; 2288 } 2289 sp = ipsec6_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error,in6p); 2290 2291 /* 2292 * There are four return cases: 2293 * sp != NULL apply IPsec policy 2294 * sp == NULL, error == 0 no IPsec handling needed 2295 * sp == NULL, error == -EINVAL discard packet w/o error 2296 * sp == NULL, error != 0 discard packet, report error 2297 */ 2298 2299 splx(s); 2300 if (sp == NULL) { 2301 /* 2302 * Caller must check the error return to see if it needs to discard 2303 * the packet. 2304 */ 2305 needipsec = 0; 2306 } else { 2307 needipsec = 1; 2308 } 2309 } 2310 skippolicycheck:; 2311 2312 *errorp = error; 2313 *needipsecp = needipsec; 2314 return sp; 2315 } 2316 2317 int 2318 ipsec6_input(struct mbuf *m) 2319 { 2320 struct secpolicy *sp; 2321 int s, error; 2322 2323 s = splsoftnet(); 2324 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 2325 if (sp != NULL) { 2326 /* 2327 * Check security policy against packet 2328 * attributes. 2329 */ 2330 error = ipsec_in_reject(sp, m); 2331 KEY_SP_UNREF(&sp); 2332 } else { 2333 /* XXX error stat??? */ 2334 error = EINVAL; 2335 IPSECLOG(LOG_DEBUG, "no SP, packet discarded\n");/*XXX*/ 2336 } 2337 splx(s); 2338 2339 return error; 2340 } 2341 #endif /* INET6 */ 2342 2343 2344 2345 /* XXX this stuff doesn't belong here... */ 2346 2347 static struct xformsw *xforms = NULL; 2348 2349 /* 2350 * Register a transform; typically at system startup. 2351 */ 2352 void 2353 xform_register(struct xformsw *xsp) 2354 { 2355 xsp->xf_next = xforms; 2356 xforms = xsp; 2357 } 2358 2359 /* 2360 * Initialize transform support in an sav. 2361 */ 2362 int 2363 xform_init(struct secasvar *sav, int xftype) 2364 { 2365 struct xformsw *xsp; 2366 2367 if (sav->tdb_xform != NULL) /* previously initialized */ 2368 return 0; 2369 for (xsp = xforms; xsp; xsp = xsp->xf_next) 2370 if (xsp->xf_type == xftype) 2371 return (*xsp->xf_init)(sav, xsp); 2372 2373 IPSECLOG(LOG_DEBUG, "no match for xform type %d\n", xftype); 2374 return EINVAL; 2375 } 2376 2377 void 2378 nat_t_ports_get(struct mbuf *m, u_int16_t *dport, u_int16_t *sport) { 2379 struct m_tag *tag; 2380 2381 if ((tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL))) { 2382 *sport = ((u_int16_t *)(tag + 1))[0]; 2383 *dport = ((u_int16_t *)(tag + 1))[1]; 2384 } else 2385 *sport = *dport = 0; 2386 } 2387 2388 /* 2389 * XXXJRT This should be done as a protosw init call. 2390 */ 2391 void 2392 ipsec_attach(void) 2393 { 2394 2395 ipsecstat_percpu = percpu_alloc(sizeof(uint64_t) * IPSEC_NSTATS); 2396 2397 sysctl_net_inet_ipsec_setup(NULL); 2398 #ifdef INET6 2399 sysctl_net_inet6_ipsec6_setup(NULL); 2400 #endif 2401 2402 ah_attach(); 2403 esp_attach(); 2404 ipcomp_attach(); 2405 ipe4_attach(); 2406 #ifdef TCP_SIGNATURE 2407 tcpsignature_attach(); 2408 #endif 2409 } 2410
Indexes created Mon Sep 22 10:09:38 GMT 2025