ipsec.c revision 1.125
1 /* $NetBSD: ipsec.c,v 1.125 2018/02/08 20:57:41 maxv Exp $ */ 2 /* $FreeBSD: /usr/local/www/cvsroot/FreeBSD/src/sys/netipsec/ipsec.c,v 1.2.2.2 2003/07/01 01:38:13 sam Exp $ */ 3 /* $KAME: ipsec.c,v 1.103 2001/05/24 07:14:18 sakane Exp $ */ 4 5 /* 6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the project nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 __KERNEL_RCSID(0, "$NetBSD: ipsec.c,v 1.125 2018/02/08 20:57:41 maxv Exp $"); 36 37 /* 38 * IPsec controller part. 39 */ 40 41 #if defined(_KERNEL_OPT) 42 #include "opt_inet.h" 43 #include "opt_ipsec.h" 44 #endif 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/mbuf.h> 49 #include <sys/domain.h> 50 #include <sys/protosw.h> 51 #include <sys/socket.h> 52 #include <sys/socketvar.h> 53 #include <sys/errno.h> 54 #include <sys/time.h> 55 #include <sys/kernel.h> 56 #include <sys/syslog.h> 57 #include <sys/sysctl.h> 58 #include <sys/proc.h> 59 #include <sys/kauth.h> 60 #include <sys/cpu.h> 61 #include <sys/kmem.h> 62 #include <sys/pserialize.h> 63 64 #include <net/if.h> 65 #include <net/route.h> 66 67 #include <netinet/in.h> 68 #include <netinet/in_systm.h> 69 #include <netinet/ip.h> 70 #include <netinet/ip_var.h> 71 #include <netinet/in_var.h> 72 #include <netinet/udp.h> 73 #include <netinet/udp_var.h> 74 #include <netinet/tcp.h> 75 #include <netinet/udp.h> 76 #include <netinet/ip_icmp.h> 77 #include <netinet/ip_private.h> 78 79 #include <netinet/ip6.h> 80 #ifdef INET6 81 #include <netinet6/ip6_var.h> 82 #endif 83 #include <netinet/in_pcb.h> 84 #ifdef INET6 85 #include <netinet6/in6_pcb.h> 86 #include <netinet/icmp6.h> 87 #endif 88 89 #include <netipsec/ipsec.h> 90 #include <netipsec/ipsec_var.h> 91 #include <netipsec/ipsec_private.h> 92 #ifdef INET6 93 #include <netipsec/ipsec6.h> 94 #endif 95 #include <netipsec/ah_var.h> 96 #include <netipsec/esp_var.h> 97 #include <netipsec/ipcomp.h> /*XXX*/ 98 #include <netipsec/ipcomp_var.h> 99 100 #include <netipsec/key.h> 101 #include <netipsec/keydb.h> 102 #include <netipsec/key_debug.h> 103 104 #include <netipsec/xform.h> 105 106 int ipsec_used = 0; 107 int ipsec_enabled = 1; 108 109 #ifdef IPSEC_DEBUG 110 int ipsec_debug = 1; 111 112 /* 113 * When set to 1, IPsec will send packets with the same sequence number. 114 * This allows to verify if the other side has proper replay attacks detection. 115 */ 116 int ipsec_replay = 0; 117 118 /* 119 * When set 1, IPsec will send packets with corrupted HMAC. 120 * This allows to verify if the other side properly detects modified packets. 121 */ 122 int ipsec_integrity = 0; 123 #else 124 int ipsec_debug = 0; 125 #endif 126 127 percpu_t *ipsecstat_percpu; 128 int ip4_ah_offsetmask = 0; /* maybe IP_DF? */ 129 int ip4_ipsec_dfbit = 2; /* DF bit on encap. 0: clear 1: set 2: copy */ 130 int ip4_esp_trans_deflev = IPSEC_LEVEL_USE; 131 int ip4_esp_net_deflev = IPSEC_LEVEL_USE; 132 int ip4_ah_trans_deflev = IPSEC_LEVEL_USE; 133 int ip4_ah_net_deflev = IPSEC_LEVEL_USE; 134 struct secpolicy ip4_def_policy; 135 int ip4_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 136 int ip4_esp_randpad = -1; 137 138 u_int ipsec_spdgen = 1; /* SPD generation # */ 139 140 static struct secpolicy ipsec_dummy_sp __read_mostly = { 141 .state = IPSEC_SPSTATE_ALIVE, 142 /* If ENTRUST, the dummy SP never be used. See ipsec_getpolicybysock. */ 143 .policy = IPSEC_POLICY_ENTRUST, 144 }; 145 146 static struct secpolicy *ipsec_checkpcbcache (struct mbuf *, 147 struct inpcbpolicy *, int); 148 static int ipsec_fillpcbcache (struct inpcbpolicy *, struct mbuf *, 149 struct secpolicy *, int); 150 static int ipsec_invalpcbcache (struct inpcbpolicy *, int); 151 152 /* 153 * Crypto support requirements: 154 * 155 * 1 require hardware support 156 * -1 require software support 157 * 0 take anything 158 */ 159 int crypto_support = 0; 160 161 static struct secpolicy *ipsec_getpolicybysock(struct mbuf *, u_int, 162 struct inpcb_hdr *, int *); 163 164 #ifdef __FreeBSD__ 165 /* net.inet.ipsec */ 166 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_ESP_RANDPAD, 167 esp_randpad, CTLFLAG_RW, &ip4_esp_randpad, 0, ""); 168 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, 169 crypto_support, CTLFLAG_RW, &crypto_support,0, ""); 170 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_replay, CTLFLAG_RW, &ipsec_replay, 0, 171 "Emulate replay attack"); 172 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_integrity, CTLFLAG_RW, 173 &ipsec_integrity, 0, "Emulate man-in-the-middle attack"); 174 #endif /* __FreeBSD__ */ 175 176 #ifdef INET6 177 int ip6_esp_trans_deflev = IPSEC_LEVEL_USE; 178 int ip6_esp_net_deflev = IPSEC_LEVEL_USE; 179 int ip6_ah_trans_deflev = IPSEC_LEVEL_USE; 180 int ip6_ah_net_deflev = IPSEC_LEVEL_USE; 181 struct secpolicy ip6_def_policy; 182 int ip6_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 183 int ip6_esp_randpad = -1; 184 185 186 #ifdef __FreeBSD__ 187 /* net.inet6.ipsec6 */ 188 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_ESP_RANDPAD, 189 esp_randpad, CTLFLAG_RW, &ip6_esp_randpad, 0, ""); 190 #endif /* __FreeBSD__ */ 191 #endif /* INET6 */ 192 193 static int ipsec4_setspidx_inpcb (struct mbuf *, struct inpcb *); 194 #ifdef INET6 195 static int ipsec6_setspidx_in6pcb (struct mbuf *, struct in6pcb *); 196 #endif 197 static int ipsec_setspidx (struct mbuf *, struct secpolicyindex *, int); 198 static void ipsec4_get_ulp (struct mbuf *m, struct secpolicyindex *, int); 199 static int ipsec4_setspidx_ipaddr (struct mbuf *, struct secpolicyindex *); 200 #ifdef INET6 201 static void ipsec6_get_ulp (struct mbuf *m, struct secpolicyindex *, int); 202 static int ipsec6_setspidx_ipaddr (struct mbuf *, struct secpolicyindex *); 203 #endif 204 static void ipsec_delpcbpolicy (struct inpcbpolicy *); 205 #if 0 /* unused */ 206 static struct secpolicy *ipsec_deepcopy_policy (const struct secpolicy *); 207 #endif 208 static int ipsec_set_policy (struct secpolicy **, int, const void *, size_t, 209 kauth_cred_t); 210 static int ipsec_get_policy (struct secpolicy *, struct mbuf **); 211 static void ipsec_destroy_policy(struct secpolicy *); 212 static void vshiftl (unsigned char *, int, int); 213 static size_t ipsec_hdrsiz(const struct secpolicy *, const struct mbuf *); 214 215 /* 216 * Try to validate and use cached policy on a PCB. 217 */ 218 static struct secpolicy * 219 ipsec_checkpcbcache(struct mbuf *m, struct inpcbpolicy *pcbsp, int dir) 220 { 221 struct secpolicyindex spidx; 222 struct secpolicy *sp = NULL; 223 int s; 224 225 KASSERT(IPSEC_DIR_IS_VALID(dir)); 226 KASSERT(pcbsp != NULL); 227 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 228 KASSERT(inph_locked(pcbsp->sp_inph)); 229 230 /* 231 * Checking the generation and sp->state and taking a reference to an SP 232 * must be in a critical section of pserialize. See key_unlink_sp. 233 */ 234 s = pserialize_read_enter(); 235 /* SPD table change invalidate all the caches. */ 236 if (ipsec_spdgen != pcbsp->sp_cache[dir].cachegen) { 237 ipsec_invalpcbcache(pcbsp, dir); 238 goto out; 239 } 240 sp = pcbsp->sp_cache[dir].cachesp; 241 if (sp == NULL) 242 goto out; 243 if (sp->state != IPSEC_SPSTATE_ALIVE) { 244 sp = NULL; 245 ipsec_invalpcbcache(pcbsp, dir); 246 goto out; 247 } 248 if ((pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) == 0) { 249 /* NB: assume ipsec_setspidx never sleep */ 250 if (ipsec_setspidx(m, &spidx, 1) != 0) { 251 sp = NULL; 252 goto out; 253 } 254 255 /* 256 * We have to make an exact match here since the cached rule 257 * might have lower priority than a rule that would otherwise 258 * have matched the packet. 259 */ 260 if (memcmp(&pcbsp->sp_cache[dir].cacheidx, &spidx, 261 sizeof(spidx))) { 262 sp = NULL; 263 goto out; 264 } 265 } else { 266 /* 267 * The pcb is connected, and the L4 code is sure that: 268 * - outgoing side uses inp_[lf]addr 269 * - incoming side looks up policy after inpcb lookup 270 * and address pair is know to be stable. We do not need 271 * to generate spidx again, nor check the address match again. 272 * 273 * For IPv4/v6 SOCK_STREAM sockets, this assumptions holds 274 * and there are calls to ipsec_pcbconn() from in_pcbconnect(). 275 */ 276 } 277 278 sp->lastused = time_second; 279 KEY_SP_REF(sp); 280 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 281 "DP cause refcnt++:%d SP:%p\n", 282 key_sp_refcnt(sp), pcbsp->sp_cache[dir].cachesp); 283 out: 284 pserialize_read_exit(s); 285 return sp; 286 } 287 288 static int 289 ipsec_fillpcbcache(struct inpcbpolicy *pcbsp, struct mbuf *m, 290 struct secpolicy *sp, int dir) 291 { 292 293 KASSERT(IPSEC_DIR_IS_INOROUT(dir)); 294 KASSERT(dir < __arraycount(pcbsp->sp_cache)); 295 KASSERT(inph_locked(pcbsp->sp_inph)); 296 297 pcbsp->sp_cache[dir].cachesp = NULL; 298 pcbsp->sp_cache[dir].cachehint = IPSEC_PCBHINT_UNKNOWN; 299 if (ipsec_setspidx(m, &pcbsp->sp_cache[dir].cacheidx, 1) != 0) { 300 return EINVAL; 301 } 302 pcbsp->sp_cache[dir].cachesp = sp; 303 if (pcbsp->sp_cache[dir].cachesp) { 304 /* 305 * If the PCB is connected, we can remember a hint to 306 * possibly short-circuit IPsec processing in other places. 307 */ 308 if (pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) { 309 switch (pcbsp->sp_cache[dir].cachesp->policy) { 310 case IPSEC_POLICY_NONE: 311 case IPSEC_POLICY_BYPASS: 312 pcbsp->sp_cache[dir].cachehint = 313 IPSEC_PCBHINT_NO; 314 break; 315 default: 316 pcbsp->sp_cache[dir].cachehint = 317 IPSEC_PCBHINT_YES; 318 } 319 } 320 } 321 pcbsp->sp_cache[dir].cachegen = ipsec_spdgen; 322 323 return 0; 324 } 325 326 static int 327 ipsec_invalpcbcache(struct inpcbpolicy *pcbsp, int dir) 328 { 329 int i; 330 331 KASSERT(inph_locked(pcbsp->sp_inph)); 332 333 for (i = IPSEC_DIR_INBOUND; i <= IPSEC_DIR_OUTBOUND; i++) { 334 if (dir != IPSEC_DIR_ANY && i != dir) 335 continue; 336 pcbsp->sp_cache[i].cachesp = NULL; 337 pcbsp->sp_cache[i].cachehint = IPSEC_PCBHINT_UNKNOWN; 338 pcbsp->sp_cache[i].cachegen = 0; 339 memset(&pcbsp->sp_cache[i].cacheidx, 0, 340 sizeof(pcbsp->sp_cache[i].cacheidx)); 341 } 342 return 0; 343 } 344 345 void 346 ipsec_pcbconn(struct inpcbpolicy *pcbsp) 347 { 348 349 KASSERT(inph_locked(pcbsp->sp_inph)); 350 351 pcbsp->sp_cacheflags |= IPSEC_PCBSP_CONNECTED; 352 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 353 } 354 355 void 356 ipsec_pcbdisconn(struct inpcbpolicy *pcbsp) 357 { 358 359 KASSERT(inph_locked(pcbsp->sp_inph)); 360 361 pcbsp->sp_cacheflags &= ~IPSEC_PCBSP_CONNECTED; 362 ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY); 363 } 364 365 void 366 ipsec_invalpcbcacheall(void) 367 { 368 369 if (ipsec_spdgen == UINT_MAX) 370 ipsec_spdgen = 1; 371 else 372 ipsec_spdgen++; 373 } 374 375 /* 376 * Return a held reference to the default SP. 377 */ 378 static struct secpolicy * 379 key_get_default_sp(int af, const char *where, int tag) 380 { 381 struct secpolicy *sp; 382 383 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP from %s:%u\n", where, tag); 384 385 switch(af) { 386 case AF_INET: 387 sp = &ip4_def_policy; 388 break; 389 #ifdef INET6 390 case AF_INET6: 391 sp = &ip6_def_policy; 392 break; 393 #endif 394 default: 395 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 396 "unexpected protocol family %u\n", af); 397 return NULL; 398 } 399 400 if (sp->policy != IPSEC_POLICY_DISCARD && 401 sp->policy != IPSEC_POLICY_NONE) { 402 IPSECLOG(LOG_INFO, "fixed system default policy: %d->%d\n", 403 sp->policy, IPSEC_POLICY_NONE); 404 sp->policy = IPSEC_POLICY_NONE; 405 } 406 KEY_SP_REF(sp); 407 408 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, "DP returns SP:%p (%u)\n", 409 sp, key_sp_refcnt(sp)); 410 return sp; 411 } 412 #define KEY_GET_DEFAULT_SP(af) \ 413 key_get_default_sp((af), __func__, __LINE__) 414 415 /* 416 * For OUTBOUND packet having a socket. Searching SPD for packet, 417 * and return a pointer to SP. 418 * OUT: NULL: no apropreate SP found, the following value is set to error. 419 * 0 : bypass 420 * EACCES : discard packet. 421 * ENOENT : ipsec_acquire() in progress, maybe. 422 * others : error occurred. 423 * others: a pointer to SP 424 * 425 * NOTE: IPv6 mapped address concern is implemented here. 426 */ 427 static struct secpolicy * 428 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb_hdr *inph, 429 int *error) 430 { 431 struct inpcbpolicy *pcbsp = NULL; 432 struct secpolicy *currsp = NULL; /* policy on socket */ 433 struct secpolicy *sp; 434 int af; 435 436 KASSERT(m != NULL); 437 KASSERT(inph != NULL); 438 KASSERT(error != NULL); 439 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 440 441 KASSERT(inph->inph_socket != NULL); 442 KASSERT(inph_locked(inph)); 443 444 /* XXX FIXME inpcb/in6pcb vs socket*/ 445 af = inph->inph_af; 446 KASSERTMSG(af == AF_INET || af == AF_INET6, 447 "unexpected protocol family %u", af); 448 449 KASSERT(inph->inph_sp != NULL); 450 /* If we have a cached entry, and if it is still valid, use it. */ 451 IPSEC_STATINC(IPSEC_STAT_SPDCACHELOOKUP); 452 currsp = ipsec_checkpcbcache(m, inph->inph_sp, dir); 453 if (currsp) { 454 *error = 0; 455 return currsp; 456 } 457 IPSEC_STATINC(IPSEC_STAT_SPDCACHEMISS); 458 459 switch (af) { 460 case AF_INET: { 461 struct inpcb *in4p = (struct inpcb *)inph; 462 /* set spidx in pcb */ 463 *error = ipsec4_setspidx_inpcb(m, in4p); 464 pcbsp = in4p->inp_sp; 465 break; 466 } 467 468 #if defined(INET6) 469 case AF_INET6: { 470 struct in6pcb *in6p = (struct in6pcb *)inph; 471 /* set spidx in pcb */ 472 *error = ipsec6_setspidx_in6pcb(m, in6p); 473 pcbsp = in6p->in6p_sp; 474 break; 475 } 476 #endif 477 default: 478 *error = EPFNOSUPPORT; 479 break; 480 } 481 if (*error) 482 return NULL; 483 484 KASSERT(pcbsp != NULL); 485 switch (dir) { 486 case IPSEC_DIR_INBOUND: 487 currsp = pcbsp->sp_in; 488 break; 489 case IPSEC_DIR_OUTBOUND: 490 currsp = pcbsp->sp_out; 491 break; 492 } 493 KASSERT(currsp != NULL); 494 495 if (pcbsp->priv) { /* when privilieged socket */ 496 switch (currsp->policy) { 497 case IPSEC_POLICY_BYPASS: 498 case IPSEC_POLICY_IPSEC: 499 KEY_SP_REF(currsp); 500 sp = currsp; 501 break; 502 503 case IPSEC_POLICY_ENTRUST: 504 /* look for a policy in SPD */ 505 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 506 if (sp == NULL) /* no SP found */ 507 sp = KEY_GET_DEFAULT_SP(af); 508 break; 509 510 default: 511 IPSECLOG(LOG_ERR, "Invalid policy for PCB %d\n", 512 currsp->policy); 513 *error = EINVAL; 514 return NULL; 515 } 516 } else { /* unpriv, SPD has policy */ 517 sp = KEY_LOOKUP_SP_BYSPIDX(&currsp->spidx, dir); 518 if (sp == NULL) { /* no SP found */ 519 switch (currsp->policy) { 520 case IPSEC_POLICY_BYPASS: 521 IPSECLOG(LOG_ERR, "Illegal policy for " 522 "non-priviliged defined %d\n", 523 currsp->policy); 524 *error = EINVAL; 525 return NULL; 526 527 case IPSEC_POLICY_ENTRUST: 528 sp = KEY_GET_DEFAULT_SP(af); 529 break; 530 531 case IPSEC_POLICY_IPSEC: 532 KEY_SP_REF(currsp); 533 sp = currsp; 534 break; 535 536 default: 537 IPSECLOG(LOG_ERR, "Invalid policy for " 538 "PCB %d\n", currsp->policy); 539 *error = EINVAL; 540 return NULL; 541 } 542 } 543 } 544 KASSERTMSG(sp != NULL, "null SP (priv %u policy %u", pcbsp->priv, 545 currsp->policy); 546 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_STAMP, 547 "DP (priv %u policy %u) allocates SP:%p (refcnt %u)\n", 548 pcbsp->priv, currsp->policy, sp, key_sp_refcnt(sp)); 549 ipsec_fillpcbcache(pcbsp, m, sp, dir); 550 return sp; 551 } 552 553 /* 554 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 555 * and return a pointer to SP. 556 * OUT: positive: a pointer to the entry for security policy leaf matched. 557 * NULL: no apropreate SP found, the following value is set to error. 558 * 0 : bypass 559 * EACCES : discard packet. 560 * ENOENT : ipsec_acquire() in progress, maybe. 561 * others : error occurred. 562 */ 563 struct secpolicy * 564 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 565 { 566 struct secpolicyindex spidx; 567 struct secpolicy *sp; 568 569 KASSERT(m != NULL); 570 KASSERT(error != NULL); 571 KASSERTMSG(IPSEC_DIR_IS_INOROUT(dir), "invalid direction %u", dir); 572 573 sp = NULL; 574 575 /* Make an index to look for a policy. */ 576 *error = ipsec_setspidx(m, &spidx, (flag & IP_FORWARDING) ? 0 : 1); 577 if (*error != 0) { 578 IPSECLOG(LOG_DEBUG, "setpidx failed, dir %u flag %u\n", dir, flag); 579 memset(&spidx, 0, sizeof (spidx)); 580 return NULL; 581 } 582 583 spidx.dir = dir; 584 585 if (key_havesp(dir)) { 586 sp = KEY_LOOKUP_SP_BYSPIDX(&spidx, dir); 587 } 588 589 if (sp == NULL) /* no SP found, use system default */ 590 sp = KEY_GET_DEFAULT_SP(spidx.dst.sa.sa_family); 591 KASSERT(sp != NULL); 592 return sp; 593 } 594 595 struct secpolicy * 596 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 597 struct inpcb *inp) 598 { 599 struct secpolicy *sp; 600 601 *error = 0; 602 603 if (inp == NULL) { 604 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 605 } else { 606 KASSERT(inp->inp_socket != NULL); 607 sp = ipsec_getpolicybysock(m, dir, (struct inpcb_hdr *)inp, error); 608 } 609 if (sp == NULL) { 610 KASSERTMSG(*error != 0, "getpolicy failed w/o error"); 611 IPSEC_STATINC(IPSEC_STAT_OUT_INVAL); 612 return NULL; 613 } 614 KASSERTMSG(*error == 0, "sp w/ error set to %u", *error); 615 switch (sp->policy) { 616 case IPSEC_POLICY_ENTRUST: 617 default: 618 printf("%s: invalid policy %u\n", __func__, sp->policy); 619 /* fall thru... */ 620 case IPSEC_POLICY_DISCARD: 621 IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO); 622 *error = -EINVAL; /* packet is discarded by caller */ 623 break; 624 case IPSEC_POLICY_BYPASS: 625 case IPSEC_POLICY_NONE: 626 KEY_SP_UNREF(&sp); 627 sp = NULL; /* NB: force NULL result */ 628 break; 629 case IPSEC_POLICY_IPSEC: 630 KASSERT(sp->req != NULL); 631 break; 632 } 633 if (*error != 0) { 634 KEY_SP_UNREF(&sp); 635 sp = NULL; 636 IPSECLOG(LOG_DEBUG, "done, error %d\n", *error); 637 } 638 return sp; 639 } 640 641 int 642 ipsec4_output(struct mbuf *m, struct inpcb *inp, int flags, 643 u_long *mtu, bool *natt_frag, bool *done) 644 { 645 struct secpolicy *sp = NULL; 646 int error, s; 647 648 /* 649 * Check the security policy (SP) for the packet and, if required, 650 * do IPsec-related processing. There are two cases here; the first 651 * time a packet is sent through it will be untagged and handled by 652 * ipsec4_checkpolicy(). If the packet is resubmitted to ip_output 653 * (e.g. after AH, ESP, etc. processing), there will be a tag to 654 * bypass the lookup and related policy checking. 655 */ 656 if (ipsec_outdone(m)) { 657 return 0; 658 } 659 s = splsoftnet(); 660 if (inp && ipsec_pcb_skip_ipsec(inp->inp_sp, IPSEC_DIR_OUTBOUND)) { 661 splx(s); 662 return 0; 663 } 664 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, inp); 665 666 /* 667 * There are four return cases: 668 * sp != NULL apply IPsec policy 669 * sp == NULL, error == 0 no IPsec handling needed 670 * sp == NULL, error == -EINVAL discard packet w/o error 671 * sp == NULL, error != 0 discard packet, report error 672 */ 673 if (sp == NULL) { 674 splx(s); 675 if (error) { 676 /* 677 * Hack: -EINVAL is used to signal that a packet 678 * should be silently discarded. This is typically 679 * because we asked key management for an SA and 680 * it was delayed (e.g. kicked up to IKE). 681 */ 682 if (error == -EINVAL) 683 error = 0; 684 m_freem(m); 685 *done = true; 686 return error; 687 } 688 /* No IPsec processing for this packet. */ 689 return 0; 690 } 691 692 /* 693 * Do delayed checksums now because we send before 694 * this is done in the normal processing path. 695 */ 696 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 697 in_delayed_cksum(m); 698 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 699 } 700 701 { 702 u_long _mtu = 0; 703 704 /* Note: callee frees mbuf */ 705 error = ipsec4_process_packet(m, sp->req, &_mtu); 706 707 if (error == 0 && _mtu != 0) { 708 /* 709 * NAT-T ESP fragmentation: do not do IPSec processing 710 * now, we will do it on each fragmented packet. 711 */ 712 *mtu = _mtu; 713 *natt_frag = true; 714 KEY_SP_UNREF(&sp); 715 splx(s); 716 return 0; 717 } 718 } 719 /* 720 * Preserve KAME behaviour: ENOENT can be returned 721 * when an SA acquire is in progress. Don't propagate 722 * this to user-level; it confuses applications. 723 * 724 * XXX this will go away when the SADB is redone. 725 */ 726 if (error == ENOENT) 727 error = 0; 728 KEY_SP_UNREF(&sp); 729 splx(s); 730 *done = true; 731 return error; 732 } 733 734 int 735 ipsec4_input(struct mbuf *m, int flags) 736 { 737 struct secpolicy *sp; 738 int error, s; 739 740 s = splsoftnet(); 741 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 742 if (sp == NULL) { 743 splx(s); 744 return EINVAL; 745 } 746 747 /* 748 * Check security policy against packet attributes. 749 */ 750 error = ipsec_in_reject(sp, m); 751 KEY_SP_UNREF(&sp); 752 splx(s); 753 if (error) { 754 return error; 755 } 756 757 if (flags == 0) { 758 /* We are done. */ 759 return 0; 760 } 761 762 /* 763 * Peek at the outbound SP for this packet to determine if 764 * it is a Fast Forward candidate. 765 */ 766 s = splsoftnet(); 767 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, NULL); 768 if (sp != NULL) { 769 m->m_flags &= ~M_CANFASTFWD; 770 KEY_SP_UNREF(&sp); 771 } 772 splx(s); 773 return 0; 774 } 775 776 int 777 ipsec4_forward(struct mbuf *m, int *destmtu) 778 { 779 /* 780 * If the packet is routed over IPsec tunnel, tell the 781 * originator the tunnel MTU. 782 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 783 * XXX quickhack!!! 784 */ 785 struct secpolicy *sp; 786 size_t ipsechdr; 787 int error; 788 789 sp = ipsec4_getpolicybyaddr(m, 790 IPSEC_DIR_OUTBOUND, IP_FORWARDING, &error); 791 if (sp == NULL) { 792 return EINVAL; 793 } 794 795 /* Count IPsec header size. */ 796 ipsechdr = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, NULL); 797 798 /* 799 * Find the correct route for outer IPv4 header, compute tunnel MTU. 800 */ 801 if (sp->req) { 802 struct secasvar *sav; 803 804 sav = ipsec_lookup_sa(sp->req, m); 805 if (sav != NULL) { 806 struct route *ro; 807 struct rtentry *rt; 808 809 ro = &sav->sah->sa_route; 810 rt = rtcache_validate(ro); 811 if (rt && rt->rt_ifp) { 812 *destmtu = rt->rt_rmx.rmx_mtu ? 813 rt->rt_rmx.rmx_mtu : rt->rt_ifp->if_mtu; 814 *destmtu -= ipsechdr; 815 } 816 rtcache_unref(rt, ro); 817 KEY_SA_UNREF(&sav); 818 } 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 kdebug_mbuf(__func__, m); 1135 } 1136 1137 /* set default */ 1138 spidx->ul_proto = IPSEC_ULPROTO_ANY; 1139 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 1140 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 1141 1142 nxt = -1; 1143 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 1144 if (off < 0 || m->m_pkthdr.len < off) 1145 return; 1146 1147 switch (nxt) { 1148 case IPPROTO_TCP: 1149 spidx->ul_proto = nxt; 1150 if (!needport) 1151 break; 1152 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 1153 break; 1154 m_copydata(m, off, sizeof(th), &th); 1155 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 1156 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 1157 break; 1158 case IPPROTO_UDP: 1159 spidx->ul_proto = nxt; 1160 if (!needport) 1161 break; 1162 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 1163 break; 1164 m_copydata(m, off, sizeof(uh), &uh); 1165 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 1166 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 1167 break; 1168 case IPPROTO_ICMPV6: 1169 spidx->ul_proto = nxt; 1170 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 1171 break; 1172 m_copydata(m, off, sizeof(icmph), &icmph); 1173 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 1174 htons((uint16_t)icmph.icmp6_type); 1175 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 1176 htons((uint16_t)icmph.icmp6_code); 1177 break; 1178 default: 1179 /* XXX intermediate headers??? */ 1180 spidx->ul_proto = nxt; 1181 break; 1182 } 1183 } 1184 1185 /* assumes that m is sane */ 1186 static int 1187 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 1188 { 1189 struct ip6_hdr *ip6 = NULL; 1190 struct ip6_hdr ip6buf; 1191 struct sockaddr_in6 *sin6; 1192 1193 if (m->m_len >= sizeof(*ip6)) 1194 ip6 = mtod(m, struct ip6_hdr *); 1195 else { 1196 m_copydata(m, 0, sizeof(ip6buf), &ip6buf); 1197 ip6 = &ip6buf; 1198 } 1199 1200 sin6 = (struct sockaddr_in6 *)&spidx->src; 1201 memset(sin6, 0, sizeof(*sin6)); 1202 sin6->sin6_family = AF_INET6; 1203 sin6->sin6_len = sizeof(struct sockaddr_in6); 1204 memcpy(&sin6->sin6_addr, &ip6->ip6_src, sizeof(ip6->ip6_src)); 1205 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 1206 sin6->sin6_addr.s6_addr16[1] = 0; 1207 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 1208 } 1209 spidx->prefs = sizeof(struct in6_addr) << 3; 1210 1211 sin6 = (struct sockaddr_in6 *)&spidx->dst; 1212 memset(sin6, 0, sizeof(*sin6)); 1213 sin6->sin6_family = AF_INET6; 1214 sin6->sin6_len = sizeof(struct sockaddr_in6); 1215 memcpy(&sin6->sin6_addr, &ip6->ip6_dst, sizeof(ip6->ip6_dst)); 1216 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 1217 sin6->sin6_addr.s6_addr16[1] = 0; 1218 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 1219 } 1220 spidx->prefd = sizeof(struct in6_addr) << 3; 1221 1222 return 0; 1223 } 1224 #endif 1225 1226 static void 1227 ipsec_delpcbpolicy(struct inpcbpolicy *p) 1228 { 1229 1230 kmem_intr_free(p, sizeof(*p)); 1231 } 1232 1233 /* initialize policy in PCB */ 1234 int 1235 ipsec_init_policy(struct socket *so, struct inpcbpolicy **policy) 1236 { 1237 struct inpcbpolicy *new; 1238 1239 KASSERT(so != NULL); 1240 KASSERT(policy != NULL); 1241 1242 new = kmem_intr_zalloc(sizeof(*new), KM_NOSLEEP); 1243 if (new == NULL) { 1244 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1245 return ENOBUFS; 1246 } 1247 1248 if (IPSEC_PRIVILEGED_SO(so)) 1249 new->priv = 1; 1250 else 1251 new->priv = 0; 1252 1253 /* 1254 * Set dummy SPs. Actual SPs will be allocated later if needed. 1255 */ 1256 new->sp_in = &ipsec_dummy_sp; 1257 new->sp_out = &ipsec_dummy_sp; 1258 1259 *policy = new; 1260 1261 return 0; 1262 } 1263 1264 #if 0 /* unused */ 1265 /* copy old ipsec policy into new */ 1266 int 1267 ipsec_copy_policy(const struct inpcbpolicy *old, struct inpcbpolicy *new) 1268 { 1269 struct secpolicy *sp; 1270 1271 sp = ipsec_deepcopy_policy(old->sp_in); 1272 if (sp) { 1273 KEY_SP_UNREF(&new->sp_in); 1274 new->sp_in = sp; 1275 } else 1276 return ENOBUFS; 1277 1278 sp = ipsec_deepcopy_policy(old->sp_out); 1279 if (sp) { 1280 KEY_SP_UNREF(&new->sp_out); 1281 new->sp_out = sp; 1282 } else 1283 return ENOBUFS; 1284 1285 new->priv = old->priv; 1286 1287 return 0; 1288 } 1289 1290 /* deep-copy a policy in PCB */ 1291 static struct secpolicy * 1292 ipsec_deepcopy_policy(const struct secpolicy *src) 1293 { 1294 struct ipsecrequest *newchain = NULL; 1295 const struct ipsecrequest *p; 1296 struct ipsecrequest **q; 1297 struct secpolicy *dst; 1298 1299 if (src == NULL) 1300 return NULL; 1301 dst = KEY_NEWSP(); 1302 if (dst == NULL) 1303 return NULL; 1304 1305 /* 1306 * deep-copy IPsec request chain. This is required since struct 1307 * ipsecrequest is not reference counted. 1308 */ 1309 q = &newchain; 1310 for (p = src->req; p; p = p->next) { 1311 *q = kmem_zalloc(sizeof(**q), KM_SLEEP); 1312 (*q)->next = NULL; 1313 1314 (*q)->saidx.proto = p->saidx.proto; 1315 (*q)->saidx.mode = p->saidx.mode; 1316 (*q)->level = p->level; 1317 (*q)->saidx.reqid = p->saidx.reqid; 1318 1319 memcpy(&(*q)->saidx.src, &p->saidx.src, sizeof((*q)->saidx.src)); 1320 memcpy(&(*q)->saidx.dst, &p->saidx.dst, sizeof((*q)->saidx.dst)); 1321 1322 (*q)->sp = dst; 1323 1324 q = &((*q)->next); 1325 } 1326 1327 dst->req = newchain; 1328 dst->state = src->state; 1329 dst->policy = src->policy; 1330 /* do not touch the refcnt fields */ 1331 1332 return dst; 1333 } 1334 #endif 1335 1336 static void 1337 ipsec_destroy_policy(struct secpolicy *sp) 1338 { 1339 1340 if (sp == &ipsec_dummy_sp) 1341 ; /* It's dummy. No need to free it. */ 1342 else { 1343 /* 1344 * We cannot destroy here because it can be called in 1345 * softint. So mark the SP as DEAD and let the timer 1346 * destroy it. See key_timehandler_spd. 1347 */ 1348 sp->state = IPSEC_SPSTATE_DEAD; 1349 } 1350 } 1351 1352 /* set policy and ipsec request if present. */ 1353 static int 1354 ipsec_set_policy( 1355 struct secpolicy **policy, 1356 int optname, 1357 const void *request, 1358 size_t len, 1359 kauth_cred_t cred 1360 ) 1361 { 1362 const struct sadb_x_policy *xpl; 1363 struct secpolicy *newsp = NULL, *oldsp; 1364 int error; 1365 1366 KASSERT(!cpu_softintr_p()); 1367 1368 /* sanity check. */ 1369 if (policy == NULL || *policy == NULL || request == NULL) 1370 return EINVAL; 1371 if (len < sizeof(*xpl)) 1372 return EINVAL; 1373 xpl = (const struct sadb_x_policy *)request; 1374 1375 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1376 kdebug_sadb_xpolicy("set passed policy", request); 1377 } 1378 1379 /* check policy type */ 1380 /* ipsec_set_policy() accepts IPSEC, ENTRUST and BYPASS. */ 1381 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 1382 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1383 return EINVAL; 1384 1385 /* check privileged socket */ 1386 if (xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1387 error = kauth_authorize_network(cred, KAUTH_NETWORK_IPSEC, 1388 KAUTH_REQ_NETWORK_IPSEC_BYPASS, NULL, NULL, NULL); 1389 if (error) 1390 return (error); 1391 } 1392 1393 /* allocation new SP entry */ 1394 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1395 return error; 1396 1397 key_init_sp(newsp); 1398 newsp->created = time_uptime; 1399 /* Insert the global list for SPs for sockets */ 1400 key_socksplist_add(newsp); 1401 1402 /* clear old SP and set new SP */ 1403 oldsp = *policy; 1404 *policy = newsp; 1405 ipsec_destroy_policy(oldsp); 1406 1407 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1408 printf("%s: new policy\n", __func__); 1409 kdebug_secpolicy(newsp); 1410 } 1411 1412 return 0; 1413 } 1414 1415 static int 1416 ipsec_get_policy(struct secpolicy *policy, struct mbuf **mp) 1417 { 1418 1419 /* sanity check. */ 1420 if (policy == NULL || mp == NULL) 1421 return EINVAL; 1422 1423 *mp = key_sp2msg(policy, M_NOWAIT); 1424 if (!*mp) { 1425 IPSECLOG(LOG_DEBUG, "No more memory.\n"); 1426 return ENOBUFS; 1427 } 1428 1429 (*mp)->m_type = MT_DATA; 1430 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DUMP)) { 1431 kdebug_mbuf(__func__, *mp); 1432 } 1433 1434 return 0; 1435 } 1436 1437 int 1438 ipsec4_set_policy(struct inpcb *inp, int optname, const void *request, 1439 size_t len, kauth_cred_t cred) 1440 { 1441 const struct sadb_x_policy *xpl; 1442 struct secpolicy **policy; 1443 1444 KASSERT(!cpu_softintr_p()); 1445 KASSERT(inp != NULL); 1446 KASSERT(inp_locked(inp)); 1447 KASSERT(request != NULL); 1448 1449 if (len < sizeof(*xpl)) 1450 return EINVAL; 1451 xpl = (const struct sadb_x_policy *)request; 1452 1453 KASSERT(inp->inp_sp != NULL); 1454 1455 /* select direction */ 1456 switch (xpl->sadb_x_policy_dir) { 1457 case IPSEC_DIR_INBOUND: 1458 policy = &inp->inp_sp->sp_in; 1459 break; 1460 case IPSEC_DIR_OUTBOUND: 1461 policy = &inp->inp_sp->sp_out; 1462 break; 1463 default: 1464 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1465 xpl->sadb_x_policy_dir); 1466 return EINVAL; 1467 } 1468 1469 return ipsec_set_policy(policy, optname, request, len, cred); 1470 } 1471 1472 int 1473 ipsec4_get_policy(struct inpcb *inp, const void *request, size_t len, 1474 struct mbuf **mp) 1475 { 1476 const struct sadb_x_policy *xpl; 1477 struct secpolicy *policy; 1478 1479 /* sanity check. */ 1480 if (inp == NULL || request == NULL || mp == NULL) 1481 return EINVAL; 1482 KASSERT(inp->inp_sp != NULL); 1483 if (len < sizeof(*xpl)) 1484 return EINVAL; 1485 xpl = (const struct sadb_x_policy *)request; 1486 1487 /* select direction */ 1488 switch (xpl->sadb_x_policy_dir) { 1489 case IPSEC_DIR_INBOUND: 1490 policy = inp->inp_sp->sp_in; 1491 break; 1492 case IPSEC_DIR_OUTBOUND: 1493 policy = inp->inp_sp->sp_out; 1494 break; 1495 default: 1496 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1497 xpl->sadb_x_policy_dir); 1498 return EINVAL; 1499 } 1500 1501 return ipsec_get_policy(policy, mp); 1502 } 1503 1504 /* delete policy in PCB */ 1505 int 1506 ipsec4_delete_pcbpolicy(struct inpcb *inp) 1507 { 1508 1509 KASSERT(inp != NULL); 1510 1511 if (inp->inp_sp == NULL) 1512 return 0; 1513 1514 if (inp->inp_sp->sp_in != NULL) 1515 ipsec_destroy_policy(inp->inp_sp->sp_in); 1516 1517 if (inp->inp_sp->sp_out != NULL) 1518 ipsec_destroy_policy(inp->inp_sp->sp_out); 1519 1520 ipsec_invalpcbcache(inp->inp_sp, IPSEC_DIR_ANY); 1521 1522 ipsec_delpcbpolicy(inp->inp_sp); 1523 inp->inp_sp = NULL; 1524 1525 return 0; 1526 } 1527 1528 #ifdef INET6 1529 int 1530 ipsec6_set_policy(struct in6pcb *in6p, int optname, const void *request, 1531 size_t len, kauth_cred_t cred) 1532 { 1533 const struct sadb_x_policy *xpl; 1534 struct secpolicy **policy; 1535 1536 KASSERT(!cpu_softintr_p()); 1537 KASSERT(in6p_locked(in6p)); 1538 1539 /* sanity check. */ 1540 if (in6p == NULL || request == NULL) 1541 return EINVAL; 1542 if (len < sizeof(*xpl)) 1543 return EINVAL; 1544 xpl = (const struct sadb_x_policy *)request; 1545 1546 /* select direction */ 1547 switch (xpl->sadb_x_policy_dir) { 1548 case IPSEC_DIR_INBOUND: 1549 policy = &in6p->in6p_sp->sp_in; 1550 break; 1551 case IPSEC_DIR_OUTBOUND: 1552 policy = &in6p->in6p_sp->sp_out; 1553 break; 1554 default: 1555 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1556 xpl->sadb_x_policy_dir); 1557 return EINVAL; 1558 } 1559 1560 return ipsec_set_policy(policy, optname, request, len, cred); 1561 } 1562 1563 int 1564 ipsec6_get_policy(struct in6pcb *in6p, const void *request, size_t len, 1565 struct mbuf **mp) 1566 { 1567 const struct sadb_x_policy *xpl; 1568 struct secpolicy *policy; 1569 1570 /* sanity check. */ 1571 if (in6p == NULL || request == NULL || mp == NULL) 1572 return EINVAL; 1573 KASSERT(in6p->in6p_sp != NULL); 1574 if (len < sizeof(*xpl)) 1575 return EINVAL; 1576 xpl = (const struct sadb_x_policy *)request; 1577 1578 /* select direction */ 1579 switch (xpl->sadb_x_policy_dir) { 1580 case IPSEC_DIR_INBOUND: 1581 policy = in6p->in6p_sp->sp_in; 1582 break; 1583 case IPSEC_DIR_OUTBOUND: 1584 policy = in6p->in6p_sp->sp_out; 1585 break; 1586 default: 1587 IPSECLOG(LOG_ERR, "invalid direction=%u\n", 1588 xpl->sadb_x_policy_dir); 1589 return EINVAL; 1590 } 1591 1592 return ipsec_get_policy(policy, mp); 1593 } 1594 1595 int 1596 ipsec6_delete_pcbpolicy(struct in6pcb *in6p) 1597 { 1598 1599 KASSERT(in6p != NULL); 1600 1601 if (in6p->in6p_sp == NULL) 1602 return 0; 1603 1604 if (in6p->in6p_sp->sp_in != NULL) 1605 ipsec_destroy_policy(in6p->in6p_sp->sp_in); 1606 1607 if (in6p->in6p_sp->sp_out != NULL) 1608 ipsec_destroy_policy(in6p->in6p_sp->sp_out); 1609 1610 ipsec_invalpcbcache(in6p->in6p_sp, IPSEC_DIR_ANY); 1611 1612 ipsec_delpcbpolicy(in6p->in6p_sp); 1613 in6p->in6p_sp = NULL; 1614 1615 return 0; 1616 } 1617 #endif 1618 1619 /* 1620 * return current level. 1621 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1622 */ 1623 u_int 1624 ipsec_get_reqlevel(const struct ipsecrequest *isr) 1625 { 1626 u_int level = 0; 1627 u_int esp_trans_deflev, esp_net_deflev; 1628 u_int ah_trans_deflev, ah_net_deflev; 1629 1630 KASSERT(isr != NULL); 1631 KASSERT(isr->sp != NULL); 1632 KASSERTMSG( 1633 isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1634 "af family mismatch, src %u, dst %u", 1635 isr->sp->spidx.src.sa.sa_family, isr->sp->spidx.dst.sa.sa_family); 1636 1637 /* XXX note that we have ipseclog() expanded here - code sync issue */ 1638 #define IPSEC_CHECK_DEFAULT(lev) \ 1639 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1640 && (lev) != IPSEC_LEVEL_UNIQUE) ? \ 1641 (ipsec_debug ? log(LOG_INFO, "fixed system default level " #lev \ 1642 ":%d->%d\n", (lev), IPSEC_LEVEL_REQUIRE) : (void)0), \ 1643 (lev) = IPSEC_LEVEL_REQUIRE, (lev) \ 1644 : (lev)) 1645 1646 /* set default level */ 1647 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1648 #ifdef INET 1649 case AF_INET: 1650 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_trans_deflev); 1651 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_net_deflev); 1652 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_trans_deflev); 1653 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_net_deflev); 1654 break; 1655 #endif 1656 #ifdef INET6 1657 case AF_INET6: 1658 esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_trans_deflev); 1659 esp_net_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_net_deflev); 1660 ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_trans_deflev); 1661 ah_net_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_net_deflev); 1662 break; 1663 #endif /* INET6 */ 1664 default: 1665 panic("%s: unknown af %u", __func__, 1666 isr->sp->spidx.src.sa.sa_family); 1667 } 1668 1669 #undef IPSEC_CHECK_DEFAULT 1670 1671 /* set level */ 1672 switch (isr->level) { 1673 case IPSEC_LEVEL_DEFAULT: 1674 switch (isr->saidx.proto) { 1675 case IPPROTO_ESP: 1676 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1677 level = esp_net_deflev; 1678 else 1679 level = esp_trans_deflev; 1680 break; 1681 case IPPROTO_AH: 1682 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1683 level = ah_net_deflev; 1684 else 1685 level = ah_trans_deflev; 1686 break; 1687 case IPPROTO_IPCOMP: 1688 /* 1689 * we don't really care, as IPcomp document says that 1690 * we shouldn't compress small packets 1691 */ 1692 level = IPSEC_LEVEL_USE; 1693 break; 1694 default: 1695 panic("%s: Illegal protocol defined %u", __func__, 1696 isr->saidx.proto); 1697 } 1698 break; 1699 1700 case IPSEC_LEVEL_USE: 1701 case IPSEC_LEVEL_REQUIRE: 1702 level = isr->level; 1703 break; 1704 case IPSEC_LEVEL_UNIQUE: 1705 level = IPSEC_LEVEL_REQUIRE; 1706 break; 1707 1708 default: 1709 panic("%s: Illegal IPsec level %u", __func__, isr->level); 1710 } 1711 1712 return level; 1713 } 1714 1715 /* 1716 * Check security policy requirements against the actual 1717 * packet contents. Return one if the packet should be 1718 * reject as "invalid"; otherwiser return zero to have the 1719 * packet treated as "valid". 1720 * 1721 * OUT: 1722 * 0: valid 1723 * 1: invalid 1724 */ 1725 int 1726 ipsec_in_reject(const struct secpolicy *sp, const struct mbuf *m) 1727 { 1728 struct ipsecrequest *isr; 1729 1730 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1731 printf("%s: using SP\n", __func__); 1732 kdebug_secpolicy(sp); 1733 } 1734 1735 /* check policy */ 1736 switch (sp->policy) { 1737 case IPSEC_POLICY_DISCARD: 1738 return 1; 1739 case IPSEC_POLICY_BYPASS: 1740 case IPSEC_POLICY_NONE: 1741 return 0; 1742 } 1743 1744 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1745 "invalid policy %u", sp->policy); 1746 1747 /* XXX should compare policy against ipsec header history */ 1748 1749 for (isr = sp->req; isr != NULL; isr = isr->next) { 1750 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1751 continue; 1752 switch (isr->saidx.proto) { 1753 case IPPROTO_ESP: 1754 if ((m->m_flags & M_DECRYPTED) == 0) { 1755 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1756 "ESP m_flags:%x\n", m->m_flags); 1757 return 1; 1758 } 1759 break; 1760 case IPPROTO_AH: 1761 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1762 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DUMP, 1763 "AH m_flags:%x\n", m->m_flags); 1764 return 1; 1765 } 1766 break; 1767 case IPPROTO_IPCOMP: 1768 /* 1769 * we don't really care, as IPcomp document 1770 * says that we shouldn't compress small 1771 * packets, IPComp policy should always be 1772 * treated as being in "use" level. 1773 */ 1774 break; 1775 } 1776 } 1777 return 0; /* valid */ 1778 } 1779 1780 /* 1781 * Check AH/ESP integrity. 1782 * This function is called from tcp_input(), udp_input(), 1783 * and {ah,esp}4_input for tunnel mode 1784 */ 1785 int 1786 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1787 { 1788 struct secpolicy *sp; 1789 int error; 1790 int result; 1791 1792 KASSERT(m != NULL); 1793 1794 /* get SP for this packet. 1795 * When we are called from ip_forward(), we call 1796 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1797 */ 1798 if (inp == NULL) 1799 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1800 else 1801 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1802 (struct inpcb_hdr *)inp, &error); 1803 1804 if (sp != NULL) { 1805 result = ipsec_in_reject(sp, m); 1806 if (result) 1807 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1808 KEY_SP_UNREF(&sp); 1809 } else { 1810 result = 0; /* XXX should be panic ? 1811 * -> No, there may be error. */ 1812 } 1813 return result; 1814 } 1815 1816 1817 #ifdef INET6 1818 /* 1819 * Check AH/ESP integrity. 1820 * This function is called from tcp6_input(), udp6_input(), 1821 * and {ah,esp}6_input for tunnel mode 1822 */ 1823 int 1824 ipsec6_in_reject(struct mbuf *m, struct in6pcb *in6p) 1825 { 1826 struct secpolicy *sp = NULL; 1827 int error; 1828 int result; 1829 1830 KASSERT(m != NULL); 1831 1832 /* get SP for this packet. 1833 * When we are called from ip_forward(), we call 1834 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1835 */ 1836 if (in6p == NULL) 1837 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1838 else 1839 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, 1840 (struct inpcb_hdr *)in6p, 1841 &error); 1842 1843 if (sp != NULL) { 1844 result = ipsec_in_reject(sp, m); 1845 if (result) 1846 IPSEC_STATINC(IPSEC_STAT_IN_POLVIO); 1847 KEY_SP_UNREF(&sp); 1848 } else { 1849 result = 0; 1850 } 1851 return result; 1852 } 1853 #endif 1854 1855 /* 1856 * compute the byte size to be occupied by IPsec header. 1857 * in case it is tunneled, it includes the size of outer IP header. 1858 * NOTE: SP passed is free in this function. 1859 */ 1860 static size_t 1861 ipsec_hdrsiz(const struct secpolicy *sp, const struct mbuf *m) 1862 { 1863 struct ipsecrequest *isr; 1864 size_t siz; 1865 1866 if (KEYDEBUG_ON(KEYDEBUG_IPSEC_DATA)) { 1867 printf("%s: using SP\n", __func__); 1868 kdebug_secpolicy(sp); 1869 } 1870 1871 switch (sp->policy) { 1872 case IPSEC_POLICY_DISCARD: 1873 case IPSEC_POLICY_BYPASS: 1874 case IPSEC_POLICY_NONE: 1875 return 0; 1876 } 1877 1878 KASSERTMSG(sp->policy == IPSEC_POLICY_IPSEC, 1879 "invalid policy %u", sp->policy); 1880 1881 siz = 0; 1882 for (isr = sp->req; isr != NULL; isr = isr->next) { 1883 size_t clen = 0; 1884 struct secasvar *sav; 1885 1886 switch (isr->saidx.proto) { 1887 case IPPROTO_ESP: 1888 sav = ipsec_lookup_sa(isr, m); 1889 if (sav != NULL) { 1890 clen = esp_hdrsiz(sav); 1891 KEY_SA_UNREF(&sav); 1892 } else 1893 clen = esp_hdrsiz(NULL); 1894 break; 1895 case IPPROTO_AH: 1896 sav = ipsec_lookup_sa(isr, m); 1897 if (sav != NULL) { 1898 clen = ah_hdrsiz(sav); 1899 KEY_SA_UNREF(&sav); 1900 } else 1901 clen = ah_hdrsiz(NULL); 1902 break; 1903 case IPPROTO_IPCOMP: 1904 clen = sizeof(struct ipcomp); 1905 break; 1906 } 1907 1908 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1909 switch (isr->saidx.dst.sa.sa_family) { 1910 case AF_INET: 1911 clen += sizeof(struct ip); 1912 break; 1913 #ifdef INET6 1914 case AF_INET6: 1915 clen += sizeof(struct ip6_hdr); 1916 break; 1917 #endif 1918 default: 1919 IPSECLOG(LOG_ERR, "unknown AF %d in " 1920 "IPsec tunnel SA\n", 1921 ((const struct sockaddr *)&isr->saidx.dst) 1922 ->sa_family); 1923 break; 1924 } 1925 } 1926 siz += clen; 1927 } 1928 1929 return siz; 1930 } 1931 1932 /* This function is called from ip_forward() and ipsec4_hdrsize_tcp(). */ 1933 size_t 1934 ipsec4_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1935 { 1936 struct secpolicy *sp; 1937 int error; 1938 size_t size; 1939 1940 KASSERT(m != NULL); 1941 KASSERTMSG(inp == NULL || inp->inp_socket != NULL, "socket w/o inpcb"); 1942 1943 /* get SP for this packet. 1944 * When we are called from ip_forward(), we call 1945 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1946 */ 1947 if (inp == NULL) 1948 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1949 else 1950 sp = ipsec_getpolicybysock(m, dir, 1951 (struct inpcb_hdr *)inp, &error); 1952 1953 if (sp != NULL) { 1954 size = ipsec_hdrsiz(sp, m); 1955 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%lu.\n", 1956 (unsigned long)size); 1957 1958 KEY_SP_UNREF(&sp); 1959 } else { 1960 size = 0; /* XXX should be panic ? */ 1961 } 1962 return size; 1963 } 1964 1965 #ifdef INET6 1966 /* This function is called from ipsec6_hdrsize_tcp(), 1967 * and maybe from ip6_forward.() 1968 */ 1969 size_t 1970 ipsec6_hdrsiz(struct mbuf *m, u_int dir, struct in6pcb *in6p) 1971 { 1972 struct secpolicy *sp; 1973 int error; 1974 size_t size; 1975 1976 KASSERT(m != NULL); 1977 KASSERTMSG(in6p == NULL || in6p->in6p_socket != NULL, 1978 "socket w/o inpcb"); 1979 1980 /* get SP for this packet */ 1981 /* XXX Is it right to call with IP_FORWARDING. */ 1982 if (in6p == NULL) 1983 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1984 else 1985 sp = ipsec_getpolicybysock(m, dir, 1986 (struct inpcb_hdr *)in6p, 1987 &error); 1988 1989 if (sp == NULL) 1990 return 0; 1991 size = ipsec_hdrsiz(sp, m); 1992 KEYDEBUG_PRINTF(KEYDEBUG_IPSEC_DATA, "size:%zu.\n", size); 1993 KEY_SP_UNREF(&sp); 1994 1995 return size; 1996 } 1997 #endif /*INET6*/ 1998 1999 /* 2000 * Check the variable replay window. 2001 * ipsec_chkreplay() performs replay check before ICV verification. 2002 * ipsec_updatereplay() updates replay bitmap. This must be called after 2003 * ICV verification (it also performs replay check, which is usually done 2004 * beforehand). 2005 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 2006 * 2007 * based on RFC 2401. 2008 */ 2009 int 2010 ipsec_chkreplay(u_int32_t seq, const struct secasvar *sav) 2011 { 2012 const struct secreplay *replay; 2013 u_int32_t diff; 2014 int fr; 2015 u_int32_t wsizeb; /* constant: bits of window size */ 2016 int frlast; /* constant: last frame */ 2017 2018 IPSEC_SPLASSERT_SOFTNET(__func__); 2019 2020 KASSERT(sav != NULL); 2021 KASSERT(sav->replay != NULL); 2022 2023 replay = sav->replay; 2024 2025 if (replay->wsize == 0) 2026 return 1; /* no need to check replay. */ 2027 2028 /* constant */ 2029 frlast = replay->wsize - 1; 2030 wsizeb = replay->wsize << 3; 2031 2032 /* sequence number of 0 is invalid */ 2033 if (seq == 0) 2034 return 0; 2035 2036 /* first time is always okay */ 2037 if (replay->count == 0) 2038 return 1; 2039 2040 if (seq > replay->lastseq) { 2041 /* larger sequences are okay */ 2042 return 1; 2043 } else { 2044 /* seq is equal or less than lastseq. */ 2045 diff = replay->lastseq - seq; 2046 2047 /* over range to check, i.e. too old or wrapped */ 2048 if (diff >= wsizeb) 2049 return 0; 2050 2051 fr = frlast - diff / 8; 2052 2053 /* this packet already seen ? */ 2054 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2055 return 0; 2056 2057 /* out of order but good */ 2058 return 1; 2059 } 2060 } 2061 2062 /* 2063 * check replay counter whether to update or not. 2064 * OUT: 0: OK 2065 * 1: NG 2066 */ 2067 int 2068 ipsec_updatereplay(u_int32_t seq, const struct secasvar *sav) 2069 { 2070 struct secreplay *replay; 2071 u_int32_t diff; 2072 int fr; 2073 u_int32_t wsizeb; /* constant: bits of window size */ 2074 int frlast; /* constant: last frame */ 2075 2076 IPSEC_SPLASSERT_SOFTNET(__func__); 2077 2078 KASSERT(sav != NULL); 2079 KASSERT(sav->replay != NULL); 2080 2081 replay = sav->replay; 2082 2083 if (replay->wsize == 0) 2084 goto ok; /* no need to check replay. */ 2085 2086 /* constant */ 2087 frlast = replay->wsize - 1; 2088 wsizeb = replay->wsize << 3; 2089 2090 /* sequence number of 0 is invalid */ 2091 if (seq == 0) 2092 return 1; 2093 2094 /* first time */ 2095 if (replay->count == 0) { 2096 replay->lastseq = seq; 2097 memset(replay->bitmap, 0, replay->wsize); 2098 (replay->bitmap)[frlast] = 1; 2099 goto ok; 2100 } 2101 2102 if (seq > replay->lastseq) { 2103 /* seq is larger than lastseq. */ 2104 diff = seq - replay->lastseq; 2105 2106 /* new larger sequence number */ 2107 if (diff < wsizeb) { 2108 /* In window */ 2109 /* set bit for this packet */ 2110 vshiftl(replay->bitmap, diff, replay->wsize); 2111 (replay->bitmap)[frlast] |= 1; 2112 } else { 2113 /* this packet has a "way larger" */ 2114 memset(replay->bitmap, 0, replay->wsize); 2115 (replay->bitmap)[frlast] = 1; 2116 } 2117 replay->lastseq = seq; 2118 2119 /* larger is good */ 2120 } else { 2121 /* seq is equal or less than lastseq. */ 2122 diff = replay->lastseq - seq; 2123 2124 /* over range to check, i.e. too old or wrapped */ 2125 if (diff >= wsizeb) 2126 return 1; 2127 2128 fr = frlast - diff / 8; 2129 2130 /* this packet already seen ? */ 2131 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 2132 return 1; 2133 2134 /* mark as seen */ 2135 (replay->bitmap)[fr] |= (1 << (diff % 8)); 2136 2137 /* out of order but good */ 2138 } 2139 2140 ok: 2141 if (replay->count == ~0) { 2142 char buf[IPSEC_LOGSASTRLEN]; 2143 2144 /* set overflow flag */ 2145 replay->overflow++; 2146 2147 /* don't increment, no more packets accepted */ 2148 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 2149 return 1; 2150 2151 IPSECLOG(LOG_WARNING, "replay counter made %d cycle. %s\n", 2152 replay->overflow, ipsec_logsastr(sav, buf, sizeof(buf))); 2153 } 2154 2155 replay->count++; 2156 2157 return 0; 2158 } 2159 2160 /* 2161 * shift variable length bunffer to left. 2162 * IN: bitmap: pointer to the buffer 2163 * nbit: the number of to shift. 2164 * wsize: buffer size (bytes). 2165 */ 2166 static void 2167 vshiftl(unsigned char *bitmap, int nbit, int wsize) 2168 { 2169 int s, j, i; 2170 unsigned char over; 2171 2172 for (j = 0; j < nbit; j += 8) { 2173 s = (nbit - j < 8) ? (nbit - j): 8; 2174 bitmap[0] <<= s; 2175 for (i = 1; i < wsize; i++) { 2176 over = (bitmap[i] >> (8 - s)); 2177 bitmap[i] <<= s; 2178 bitmap[i-1] |= over; 2179 } 2180 } 2181 2182 return; 2183 } 2184 2185 /* Return a printable string for the address. */ 2186 const char * 2187 ipsec_address(const union sockaddr_union *sa, char *buf, size_t size) 2188 { 2189 switch (sa->sa.sa_family) { 2190 #if INET 2191 case AF_INET: 2192 in_print(buf, size, &sa->sin.sin_addr); 2193 return buf; 2194 #endif /* INET */ 2195 2196 #if INET6 2197 case AF_INET6: 2198 in6_print(buf, size, &sa->sin6.sin6_addr); 2199 return buf; 2200 #endif /* INET6 */ 2201 2202 default: 2203 return "(unknown address family)"; 2204 } 2205 } 2206 2207 const char * 2208 ipsec_logsastr(const struct secasvar *sav, char *buf, size_t size) 2209 { 2210 const struct secasindex *saidx = &sav->sah->saidx; 2211 char sbuf[IPSEC_ADDRSTRLEN], dbuf[IPSEC_ADDRSTRLEN]; 2212 2213 KASSERTMSG(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 2214 "af family mismatch, src %u, dst %u", 2215 saidx->src.sa.sa_family, saidx->dst.sa.sa_family); 2216 2217 snprintf(buf, size, "SA(SPI=%u src=%s dst=%s)", 2218 (u_int32_t)ntohl(sav->spi), 2219 ipsec_address(&saidx->src, sbuf, sizeof(sbuf)), 2220 ipsec_address(&saidx->dst, dbuf, sizeof(dbuf))); 2221 2222 return buf; 2223 } 2224 2225 void 2226 ipsec_dumpmbuf(struct mbuf *m) 2227 { 2228 int totlen; 2229 int i; 2230 u_char *p; 2231 2232 totlen = 0; 2233 printf("---\n"); 2234 while (m) { 2235 p = mtod(m, u_char *); 2236 for (i = 0; i < m->m_len; i++) { 2237 printf("%02x ", p[i]); 2238 totlen++; 2239 if (totlen % 16 == 0) 2240 printf("\n"); 2241 } 2242 m = m->m_next; 2243 } 2244 if (totlen % 16 != 0) 2245 printf("\n"); 2246 printf("---\n"); 2247 } 2248 2249 #ifdef INET6 2250 struct secpolicy * 2251 ipsec6_check_policy(struct mbuf *m, struct in6pcb *in6p, 2252 int flags, int *needipsecp, int *errorp) 2253 { 2254 struct secpolicy *sp = NULL; 2255 int s; 2256 int error = 0; 2257 int needipsec = 0; 2258 2259 if (!ipsec_outdone(m)) { 2260 s = splsoftnet(); 2261 if (in6p != NULL && 2262 ipsec_pcb_skip_ipsec(in6p->in6p_sp, IPSEC_DIR_OUTBOUND)) { 2263 splx(s); 2264 goto skippolicycheck; 2265 } 2266 sp = ipsec6_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error,in6p); 2267 2268 /* 2269 * There are four return cases: 2270 * sp != NULL apply IPsec policy 2271 * sp == NULL, error == 0 no IPsec handling needed 2272 * sp == NULL, error == -EINVAL discard packet w/o error 2273 * sp == NULL, error != 0 discard packet, report error 2274 */ 2275 2276 splx(s); 2277 if (sp == NULL) { 2278 /* 2279 * Caller must check the error return to see if it needs to discard 2280 * the packet. 2281 */ 2282 needipsec = 0; 2283 } else { 2284 needipsec = 1; 2285 } 2286 } 2287 skippolicycheck:; 2288 2289 *errorp = error; 2290 *needipsecp = needipsec; 2291 return sp; 2292 } 2293 2294 int 2295 ipsec6_input(struct mbuf *m) 2296 { 2297 struct secpolicy *sp; 2298 int s, error; 2299 2300 s = splsoftnet(); 2301 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 2302 if (sp != NULL) { 2303 /* 2304 * Check security policy against packet 2305 * attributes. 2306 */ 2307 error = ipsec_in_reject(sp, m); 2308 KEY_SP_UNREF(&sp); 2309 } else { 2310 /* XXX error stat??? */ 2311 error = EINVAL; 2312 IPSECLOG(LOG_DEBUG, "no SP, packet discarded\n");/*XXX*/ 2313 } 2314 splx(s); 2315 2316 return error; 2317 } 2318 #endif /* INET6 */ 2319 2320 2321 2322 /* XXX this stuff doesn't belong here... */ 2323 2324 static struct xformsw *xforms = NULL; 2325 2326 /* 2327 * Register a transform; typically at system startup. 2328 */ 2329 void 2330 xform_register(struct xformsw *xsp) 2331 { 2332 xsp->xf_next = xforms; 2333 xforms = xsp; 2334 } 2335 2336 /* 2337 * Initialize transform support in an sav. 2338 */ 2339 int 2340 xform_init(struct secasvar *sav, int xftype) 2341 { 2342 struct xformsw *xsp; 2343 2344 if (sav->tdb_xform != NULL) /* previously initialized */ 2345 return 0; 2346 for (xsp = xforms; xsp; xsp = xsp->xf_next) 2347 if (xsp->xf_type == xftype) 2348 return (*xsp->xf_init)(sav, xsp); 2349 2350 IPSECLOG(LOG_DEBUG, "no match for xform type %d\n", xftype); 2351 return EINVAL; 2352 } 2353 2354 void 2355 nat_t_ports_get(struct mbuf *m, u_int16_t *dport, u_int16_t *sport) { 2356 struct m_tag *tag; 2357 2358 if ((tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL))) { 2359 *sport = ((u_int16_t *)(tag + 1))[0]; 2360 *dport = ((u_int16_t *)(tag + 1))[1]; 2361 } else 2362 *sport = *dport = 0; 2363 } 2364 2365 /* 2366 * XXXJRT This should be done as a protosw init call. 2367 */ 2368 void 2369 ipsec_attach(void) 2370 { 2371 2372 ipsec_output_init(); 2373 2374 ipsecstat_percpu = percpu_alloc(sizeof(uint64_t) * IPSEC_NSTATS); 2375 2376 sysctl_net_inet_ipsec_setup(NULL); 2377 #ifdef INET6 2378 sysctl_net_inet6_ipsec6_setup(NULL); 2379 #endif 2380 2381 ah_attach(); 2382 esp_attach(); 2383 ipcomp_attach(); 2384 ipe4_attach(); 2385 #ifdef TCP_SIGNATURE 2386 tcpsignature_attach(); 2387 #endif 2388 } 2389
Indexes created Tue Sep 30 10:09:55 GMT 2025