1 /* $FreeBSD$ */ 2 /* $KAME: ipsec.c,v 1.103 2001/05/24 07:14:18 sakane Exp $ */ 3 4 /*- 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * IPsec controller part. 35 */ 36 37 #include "opt_inet.h" 38 #include "opt_inet6.h" 39 #include "opt_ipsec.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/malloc.h> 44 #include <sys/mbuf.h> 45 #include <sys/domain.h> 46 #include <sys/priv.h> 47 #include <sys/protosw.h> 48 #include <sys/socket.h> 49 #include <sys/socketvar.h> 50 #include <sys/errno.h> 51 #include <sys/hhook.h> 52 #include <sys/time.h> 53 #include <sys/kernel.h> 54 #include <sys/syslog.h> 55 #include <sys/sysctl.h> 56 #include <sys/proc.h> 57 58 #include <net/if.h> 59 #include <net/if_enc.h> 60 #include <net/if_var.h> 61 #include <net/vnet.h> 62 63 #include <netinet/in.h> 64 #include <netinet/in_systm.h> 65 #include <netinet/ip.h> 66 #include <netinet/ip_var.h> 67 #include <netinet/in_var.h> 68 #include <netinet/udp.h> 69 #include <netinet/udp_var.h> 70 #include <netinet/tcp.h> 71 #include <netinet/udp.h> 72 73 #include <netinet/ip6.h> 74 #ifdef INET6 75 #include <netinet6/ip6_var.h> 76 #endif 77 #include <netinet/in_pcb.h> 78 #ifdef INET6 79 #include <netinet/icmp6.h> 80 #endif 81 82 #include <sys/types.h> 83 #include <netipsec/ipsec.h> 84 #ifdef INET6 85 #include <netipsec/ipsec6.h> 86 #endif 87 #include <netipsec/ah_var.h> 88 #include <netipsec/esp_var.h> 89 #include <netipsec/ipcomp.h> /*XXX*/ 90 #include <netipsec/ipcomp_var.h> 91 92 #include <netipsec/key.h> 93 #include <netipsec/keydb.h> 94 #include <netipsec/key_debug.h> 95 96 #include <netipsec/xform.h> 97 98 #include <machine/in_cksum.h> 99 100 #include <opencrypto/cryptodev.h> 101 102 #ifdef IPSEC_DEBUG 103 VNET_DEFINE(int, ipsec_debug) = 1; 104 #else 105 VNET_DEFINE(int, ipsec_debug) = 0; 106 #endif 107 108 /* NB: name changed so netstat doesn't use it. */ 109 VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec4stat); 110 VNET_PCPUSTAT_SYSINIT(ipsec4stat); 111 112 #ifdef VIMAGE 113 VNET_PCPUSTAT_SYSUNINIT(ipsec4stat); 114 #endif /* VIMAGE */ 115 116 VNET_DEFINE(int, ip4_ah_offsetmask) = 0; /* maybe IP_DF? */ 117 /* DF bit on encap. 0: clear 1: set 2: copy */ 118 VNET_DEFINE(int, ip4_ipsec_dfbit) = 0; 119 VNET_DEFINE(int, ip4_esp_trans_deflev) = IPSEC_LEVEL_USE; 120 VNET_DEFINE(int, ip4_esp_net_deflev) = IPSEC_LEVEL_USE; 121 VNET_DEFINE(int, ip4_ah_trans_deflev) = IPSEC_LEVEL_USE; 122 VNET_DEFINE(int, ip4_ah_net_deflev) = IPSEC_LEVEL_USE; 123 /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 124 VNET_DEFINE(int, ip4_ipsec_ecn) = 0; 125 VNET_DEFINE(int, ip4_esp_randpad) = -1; 126 127 static VNET_DEFINE(struct secpolicy, def_policy); 128 #define V_def_policy VNET(def_policy) 129 /* 130 * Crypto support requirements: 131 * 132 * 1 require hardware support 133 * -1 require software support 134 * 0 take anything 135 */ 136 VNET_DEFINE(int, crypto_support) = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE; 137 138 FEATURE(ipsec, "Internet Protocol Security (IPsec)"); 139 #ifdef IPSEC_NAT_T 140 FEATURE(ipsec_natt, "UDP Encapsulation of IPsec ESP Packets ('NAT-T')"); 141 #endif 142 143 SYSCTL_DECL(_net_inet_ipsec); 144 145 /* net.inet.ipsec */ 146 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy, 147 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(def_policy).policy, 0, 148 "IPsec default policy."); 149 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev, 150 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_esp_trans_deflev), 0, 151 "Default ESP transport mode level"); 152 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev, 153 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_esp_net_deflev), 0, 154 "Default ESP tunnel mode level."); 155 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev, 156 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ah_trans_deflev), 0, 157 "AH transfer mode default level."); 158 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev, 159 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ah_net_deflev), 0, 160 "AH tunnel mode default level."); 161 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos, 162 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ah_cleartos), 0, 163 "If set clear type-of-service field when doing AH computation."); 164 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, ah_offsetmask, 165 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ah_offsetmask), 0, 166 "If not set clear offset field mask when doing AH computation."); 167 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit, 168 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ipsec_dfbit), 0, 169 "Do not fragment bit on encap."); 170 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn, 171 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ipsec_ecn), 0, 172 "Explicit Congestion Notification handling."); 173 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEBUG, debug, 174 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0, 175 "Enable IPsec debugging output when set."); 176 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, crypto_support, 177 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(crypto_support), 0, 178 "Crypto driver selection."); 179 SYSCTL_VNET_PCPUSTAT(_net_inet_ipsec, OID_AUTO, ipsecstats, struct ipsecstat, 180 ipsec4stat, "IPsec IPv4 statistics."); 181 182 #ifdef REGRESSION 183 /* 184 * When set to 1, IPsec will send packets with the same sequence number. 185 * This allows to verify if the other side has proper replay attacks detection. 186 */ 187 VNET_DEFINE(int, ipsec_replay) = 0; 188 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_replay, 189 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipsec_replay), 0, 190 "Emulate replay attack"); 191 /* 192 * When set 1, IPsec will send packets with corrupted HMAC. 193 * This allows to verify if the other side properly detects modified packets. 194 */ 195 VNET_DEFINE(int, ipsec_integrity) = 0; 196 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_integrity, 197 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipsec_integrity), 0, 198 "Emulate man-in-the-middle attack"); 199 #endif 200 201 #ifdef INET6 202 VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec6stat); 203 VNET_PCPUSTAT_SYSINIT(ipsec6stat); 204 205 #ifdef VIMAGE 206 VNET_PCPUSTAT_SYSUNINIT(ipsec6stat); 207 #endif /* VIMAGE */ 208 209 VNET_DEFINE(int, ip6_esp_trans_deflev) = IPSEC_LEVEL_USE; 210 VNET_DEFINE(int, ip6_esp_net_deflev) = IPSEC_LEVEL_USE; 211 VNET_DEFINE(int, ip6_ah_trans_deflev) = IPSEC_LEVEL_USE; 212 VNET_DEFINE(int, ip6_ah_net_deflev) = IPSEC_LEVEL_USE; 213 VNET_DEFINE(int, ip6_ipsec_ecn) = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 214 215 SYSCTL_DECL(_net_inet6_ipsec6); 216 217 /* net.inet6.ipsec6 */ 218 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy, 219 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(def_policy).policy, 0, 220 "IPsec default policy."); 221 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev, 222 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_esp_trans_deflev), 0, 223 "Default ESP transport mode level."); 224 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev, 225 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_esp_net_deflev), 0, 226 "Default ESP tunnel mode level."); 227 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev, 228 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ah_trans_deflev), 0, 229 "AH transfer mode default level."); 230 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev, 231 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ah_net_deflev), 0, 232 "AH tunnel mode default level."); 233 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_ECN, ecn, 234 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ipsec_ecn), 0, 235 "Explicit Congestion Notification handling."); 236 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEBUG, debug, 237 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0, 238 "Enable IPsec debugging output when set."); 239 SYSCTL_VNET_PCPUSTAT(_net_inet6_ipsec6, IPSECCTL_STATS, ipsecstats, 240 struct ipsecstat, ipsec6stat, "IPsec IPv6 statistics."); 241 #endif /* INET6 */ 242 243 static int ipsec_in_reject(struct secpolicy *, const struct mbuf *); 244 static int ipsec_setspidx_inpcb(const struct mbuf *, struct inpcb *); 245 static int ipsec_setspidx(const struct mbuf *, struct secpolicyindex *, int); 246 static void ipsec4_get_ulp(const struct mbuf *m, struct secpolicyindex *, int); 247 static int ipsec4_setspidx_ipaddr(const struct mbuf *, struct secpolicyindex *); 248 #ifdef INET6 249 static void ipsec6_get_ulp(const struct mbuf *m, struct secpolicyindex *, int); 250 static int ipsec6_setspidx_ipaddr(const struct mbuf *, struct secpolicyindex *); 251 #endif 252 static void ipsec_delpcbpolicy(struct inpcbpolicy *); 253 static struct secpolicy *ipsec_deepcopy_policy(struct secpolicy *src); 254 255 MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy"); 256 257 /* 258 * Return a held reference to the default SP. 259 */ 260 static struct secpolicy * 261 key_allocsp_default(const char* where, int tag) 262 { 263 struct secpolicy *sp; 264 265 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 266 printf("DP key_allocsp_default from %s:%u\n", where, tag)); 267 268 sp = &V_def_policy; 269 if (sp->policy != IPSEC_POLICY_DISCARD && 270 sp->policy != IPSEC_POLICY_NONE) { 271 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n", 272 sp->policy, IPSEC_POLICY_NONE)); 273 sp->policy = IPSEC_POLICY_NONE; 274 } 275 key_addref(sp); 276 277 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 278 printf("DP key_allocsp_default returns SP:%p (%u)\n", 279 sp, sp->refcnt)); 280 return (sp); 281 } 282 #define KEY_ALLOCSP_DEFAULT() \ 283 key_allocsp_default(__FILE__, __LINE__) 284 285 /* 286 * For OUTBOUND packet having a socket. Searching SPD for packet, 287 * and return a pointer to SP. 288 * OUT: NULL: no apropreate SP found, the following value is set to error. 289 * 0 : bypass 290 * EACCES : discard packet. 291 * ENOENT : ipsec_acquire() in progress, maybe. 292 * others : error occurred. 293 * others: a pointer to SP 294 * 295 * NOTE: IPv6 mapped adddress concern is implemented here. 296 */ 297 struct secpolicy * 298 ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir) 299 { 300 struct secpolicy *sp; 301 302 IPSEC_ASSERT(tdbi != NULL, ("null tdbi")); 303 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 304 ("invalid direction %u", dir)); 305 306 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir); 307 if (sp == NULL) /*XXX????*/ 308 sp = KEY_ALLOCSP_DEFAULT(); 309 IPSEC_ASSERT(sp != NULL, ("null SP")); 310 return (sp); 311 } 312 313 /* 314 * For OUTBOUND packet having a socket. Searching SPD for packet, 315 * and return a pointer to SP. 316 * OUT: NULL: no apropreate SP found, the following value is set to error. 317 * 0 : bypass 318 * EACCES : discard packet. 319 * ENOENT : ipsec_acquire() in progress, maybe. 320 * others : error occurred. 321 * others: a pointer to SP 322 * 323 * NOTE: IPv6 mapped adddress concern is implemented here. 324 */ 325 static struct secpolicy * 326 ipsec_getpolicybysock(const struct mbuf *m, u_int dir, struct inpcb *inp, 327 int *error) 328 { 329 struct inpcbpolicy *pcbsp; 330 struct secpolicy *currsp = NULL; /* Policy on socket. */ 331 struct secpolicy *sp; 332 333 IPSEC_ASSERT(m != NULL, ("null mbuf")); 334 IPSEC_ASSERT(inp != NULL, ("null inpcb")); 335 IPSEC_ASSERT(error != NULL, ("null error")); 336 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 337 ("invalid direction %u", dir)); 338 339 if (!key_havesp(dir)) { 340 /* No SP found, use system default. */ 341 sp = KEY_ALLOCSP_DEFAULT(); 342 return (sp); 343 } 344 345 /* Set spidx in pcb. */ 346 *error = ipsec_setspidx_inpcb(m, inp); 347 if (*error) 348 return (NULL); 349 350 pcbsp = inp->inp_sp; 351 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp")); 352 switch (dir) { 353 case IPSEC_DIR_INBOUND: 354 currsp = pcbsp->sp_in; 355 break; 356 case IPSEC_DIR_OUTBOUND: 357 currsp = pcbsp->sp_out; 358 break; 359 } 360 IPSEC_ASSERT(currsp != NULL, ("null currsp")); 361 362 if (pcbsp->priv) { /* When privilieged socket. */ 363 switch (currsp->policy) { 364 case IPSEC_POLICY_BYPASS: 365 case IPSEC_POLICY_IPSEC: 366 key_addref(currsp); 367 sp = currsp; 368 break; 369 370 case IPSEC_POLICY_ENTRUST: 371 /* Look for a policy in SPD. */ 372 sp = KEY_ALLOCSP(&currsp->spidx, dir); 373 if (sp == NULL) /* No SP found. */ 374 sp = KEY_ALLOCSP_DEFAULT(); 375 break; 376 377 default: 378 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n", 379 __func__, currsp->policy)); 380 *error = EINVAL; 381 return (NULL); 382 } 383 } else { /* Unpriv, SPD has policy. */ 384 sp = KEY_ALLOCSP(&currsp->spidx, dir); 385 if (sp == NULL) { /* No SP found. */ 386 switch (currsp->policy) { 387 case IPSEC_POLICY_BYPASS: 388 ipseclog((LOG_ERR, "%s: Illegal policy for " 389 "non-priviliged defined %d\n", 390 __func__, currsp->policy)); 391 *error = EINVAL; 392 return (NULL); 393 394 case IPSEC_POLICY_ENTRUST: 395 sp = KEY_ALLOCSP_DEFAULT(); 396 break; 397 398 case IPSEC_POLICY_IPSEC: 399 key_addref(currsp); 400 sp = currsp; 401 break; 402 403 default: 404 ipseclog((LOG_ERR, "%s: Invalid policy for " 405 "PCB %d\n", __func__, currsp->policy)); 406 *error = EINVAL; 407 return (NULL); 408 } 409 } 410 } 411 IPSEC_ASSERT(sp != NULL, 412 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy)); 413 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 414 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n", 415 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt)); 416 return (sp); 417 } 418 419 /* 420 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 421 * and return a pointer to SP. 422 * OUT: positive: a pointer to the entry for security policy leaf matched. 423 * NULL: no apropreate SP found, the following value is set to error. 424 * 0 : bypass 425 * EACCES : discard packet. 426 * ENOENT : ipsec_acquire() in progress, maybe. 427 * others : error occurred. 428 */ 429 struct secpolicy * 430 ipsec_getpolicybyaddr(const struct mbuf *m, u_int dir, int *error) 431 { 432 struct secpolicyindex spidx; 433 struct secpolicy *sp; 434 435 IPSEC_ASSERT(m != NULL, ("null mbuf")); 436 IPSEC_ASSERT(error != NULL, ("null error")); 437 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 438 ("invalid direction %u", dir)); 439 440 sp = NULL; 441 *error = 0; 442 if (key_havesp(dir)) { 443 /* Make an index to look for a policy. */ 444 *error = ipsec_setspidx(m, &spidx, 0); 445 if (*error != 0) { 446 DPRINTF(("%s: setpidx failed, dir %u\n", 447 __func__, dir)); 448 return (NULL); 449 } 450 spidx.dir = dir; 451 sp = KEY_ALLOCSP(&spidx, dir); 452 } 453 if (sp == NULL) /* No SP found, use system default. */ 454 sp = KEY_ALLOCSP_DEFAULT(); 455 IPSEC_ASSERT(sp != NULL, ("null SP")); 456 return (sp); 457 } 458 459 struct secpolicy * 460 ipsec4_checkpolicy(const struct mbuf *m, u_int dir, int *error, 461 struct inpcb *inp) 462 { 463 struct secpolicy *sp; 464 465 *error = 0; 466 if (inp == NULL) 467 sp = ipsec_getpolicybyaddr(m, dir, error); 468 else 469 sp = ipsec_getpolicybysock(m, dir, inp, error); 470 if (sp == NULL) { 471 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error")); 472 IPSECSTAT_INC(ips_out_inval); 473 return (NULL); 474 } 475 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error)); 476 switch (sp->policy) { 477 case IPSEC_POLICY_ENTRUST: 478 default: 479 printf("%s: invalid policy %u\n", __func__, sp->policy); 480 /* FALLTHROUGH */ 481 case IPSEC_POLICY_DISCARD: 482 IPSECSTAT_INC(ips_out_polvio); 483 *error = -EINVAL; /* Packet is discarded by caller. */ 484 break; 485 case IPSEC_POLICY_BYPASS: 486 case IPSEC_POLICY_NONE: 487 KEY_FREESP(&sp); 488 sp = NULL; /* NB: force NULL result. */ 489 break; 490 case IPSEC_POLICY_IPSEC: 491 if (sp->req == NULL) /* Acquire a SA. */ 492 *error = key_spdacquire(sp); 493 break; 494 } 495 if (*error != 0) { 496 KEY_FREESP(&sp); 497 sp = NULL; 498 } 499 return (sp); 500 } 501 502 static int 503 ipsec_setspidx_inpcb(const struct mbuf *m, struct inpcb *inp) 504 { 505 int error; 506 507 IPSEC_ASSERT(inp != NULL, ("null inp")); 508 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 509 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL, 510 ("null sp_in || sp_out")); 511 512 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1); 513 if (error == 0) { 514 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 515 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx; 516 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 517 } else { 518 bzero(&inp->inp_sp->sp_in->spidx, 519 sizeof (inp->inp_sp->sp_in->spidx)); 520 bzero(&inp->inp_sp->sp_out->spidx, 521 sizeof (inp->inp_sp->sp_in->spidx)); 522 } 523 return (error); 524 } 525 526 /* 527 * Configure security policy index (src/dst/proto/sport/dport) 528 * by looking at the content of mbuf. 529 * The caller is responsible for error recovery (like clearing up spidx). 530 */ 531 static int 532 ipsec_setspidx(const struct mbuf *m, struct secpolicyindex *spidx, 533 int needport) 534 { 535 struct ip ipbuf; 536 const struct ip *ip = NULL; 537 const struct mbuf *n; 538 u_int v; 539 int len; 540 int error; 541 542 IPSEC_ASSERT(m != NULL, ("null mbuf")); 543 544 /* 545 * Validate m->m_pkthdr.len. We see incorrect length if we 546 * mistakenly call this function with inconsistent mbuf chain 547 * (like 4.4BSD tcp/udp processing). XXX Should we panic here? 548 */ 549 len = 0; 550 for (n = m; n; n = n->m_next) 551 len += n->m_len; 552 if (m->m_pkthdr.len != len) { 553 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 554 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n", 555 __func__, len, m->m_pkthdr.len)); 556 return (EINVAL); 557 } 558 559 if (m->m_pkthdr.len < sizeof(struct ip)) { 560 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 561 printf("%s: pkthdr len(%d) too small (v4), ignored.\n", 562 __func__, m->m_pkthdr.len)); 563 return (EINVAL); 564 } 565 566 if (m->m_len >= sizeof(*ip)) 567 ip = mtod(m, const struct ip *); 568 else { 569 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf); 570 ip = &ipbuf; 571 } 572 v = ip->ip_v; 573 switch (v) { 574 case 4: 575 error = ipsec4_setspidx_ipaddr(m, spidx); 576 if (error) 577 return (error); 578 ipsec4_get_ulp(m, spidx, needport); 579 return (0); 580 #ifdef INET6 581 case 6: 582 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 583 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 584 printf("%s: pkthdr len(%d) too small (v6), " 585 "ignored\n", __func__, m->m_pkthdr.len)); 586 return (EINVAL); 587 } 588 error = ipsec6_setspidx_ipaddr(m, spidx); 589 if (error) 590 return (error); 591 ipsec6_get_ulp(m, spidx, needport); 592 return (0); 593 #endif 594 default: 595 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 596 printf("%s: " "unknown IP version %u, ignored.\n", 597 __func__, v)); 598 return (EINVAL); 599 } 600 } 601 602 static void 603 ipsec4_get_ulp(const struct mbuf *m, struct secpolicyindex *spidx, 604 int needport) 605 { 606 u_int8_t nxt; 607 int off; 608 609 /* Sanity check. */ 610 IPSEC_ASSERT(m != NULL, ("null mbuf")); 611 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short")); 612 613 if (m->m_len >= sizeof (struct ip)) { 614 const struct ip *ip = mtod(m, const struct ip *); 615 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 616 goto done; 617 off = ip->ip_hl << 2; 618 nxt = ip->ip_p; 619 } else { 620 struct ip ih; 621 622 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih); 623 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 624 goto done; 625 off = ih.ip_hl << 2; 626 nxt = ih.ip_p; 627 } 628 629 while (off < m->m_pkthdr.len) { 630 struct ip6_ext ip6e; 631 struct tcphdr th; 632 struct udphdr uh; 633 634 switch (nxt) { 635 case IPPROTO_TCP: 636 spidx->ul_proto = nxt; 637 if (!needport) 638 goto done_proto; 639 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 640 goto done; 641 m_copydata(m, off, sizeof (th), (caddr_t) &th); 642 spidx->src.sin.sin_port = th.th_sport; 643 spidx->dst.sin.sin_port = th.th_dport; 644 return; 645 case IPPROTO_UDP: 646 spidx->ul_proto = nxt; 647 if (!needport) 648 goto done_proto; 649 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 650 goto done; 651 m_copydata(m, off, sizeof (uh), (caddr_t) &uh); 652 spidx->src.sin.sin_port = uh.uh_sport; 653 spidx->dst.sin.sin_port = uh.uh_dport; 654 return; 655 case IPPROTO_AH: 656 if (off + sizeof(ip6e) > m->m_pkthdr.len) 657 goto done; 658 /* XXX Sigh, this works but is totally bogus. */ 659 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e); 660 off += (ip6e.ip6e_len + 2) << 2; 661 nxt = ip6e.ip6e_nxt; 662 break; 663 case IPPROTO_ICMP: 664 default: 665 /* XXX Intermediate headers??? */ 666 spidx->ul_proto = nxt; 667 goto done_proto; 668 } 669 } 670 done: 671 spidx->ul_proto = IPSEC_ULPROTO_ANY; 672 done_proto: 673 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 674 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 675 } 676 677 /* Assumes that m is sane. */ 678 static int 679 ipsec4_setspidx_ipaddr(const struct mbuf *m, struct secpolicyindex *spidx) 680 { 681 static const struct sockaddr_in template = { 682 sizeof (struct sockaddr_in), 683 AF_INET, 684 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 685 }; 686 687 spidx->src.sin = template; 688 spidx->dst.sin = template; 689 690 if (m->m_len < sizeof (struct ip)) { 691 m_copydata(m, offsetof(struct ip, ip_src), 692 sizeof (struct in_addr), 693 (caddr_t) &spidx->src.sin.sin_addr); 694 m_copydata(m, offsetof(struct ip, ip_dst), 695 sizeof (struct in_addr), 696 (caddr_t) &spidx->dst.sin.sin_addr); 697 } else { 698 const struct ip *ip = mtod(m, const struct ip *); 699 spidx->src.sin.sin_addr = ip->ip_src; 700 spidx->dst.sin.sin_addr = ip->ip_dst; 701 } 702 703 spidx->prefs = sizeof(struct in_addr) << 3; 704 spidx->prefd = sizeof(struct in_addr) << 3; 705 706 return (0); 707 } 708 709 #ifdef INET6 710 static void 711 ipsec6_get_ulp(const struct mbuf *m, struct secpolicyindex *spidx, 712 int needport) 713 { 714 int off, nxt; 715 struct tcphdr th; 716 struct udphdr uh; 717 struct icmp6_hdr ih; 718 719 /* Sanity check. */ 720 if (m == NULL) 721 panic("%s: NULL pointer was passed.\n", __func__); 722 723 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 724 printf("%s:\n", __func__); kdebug_mbuf(m)); 725 726 /* Set default. */ 727 spidx->ul_proto = IPSEC_ULPROTO_ANY; 728 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 729 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 730 731 nxt = -1; 732 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 733 if (off < 0 || m->m_pkthdr.len < off) 734 return; 735 736 switch (nxt) { 737 case IPPROTO_TCP: 738 spidx->ul_proto = nxt; 739 if (!needport) 740 break; 741 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 742 break; 743 m_copydata(m, off, sizeof(th), (caddr_t)&th); 744 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 745 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 746 break; 747 case IPPROTO_UDP: 748 spidx->ul_proto = nxt; 749 if (!needport) 750 break; 751 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 752 break; 753 m_copydata(m, off, sizeof(uh), (caddr_t)&uh); 754 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 755 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 756 break; 757 case IPPROTO_ICMPV6: 758 spidx->ul_proto = nxt; 759 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 760 break; 761 m_copydata(m, off, sizeof(ih), (caddr_t)&ih); 762 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 763 htons((uint16_t)ih.icmp6_type); 764 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 765 htons((uint16_t)ih.icmp6_code); 766 break; 767 default: 768 /* XXX Intermediate headers??? */ 769 spidx->ul_proto = nxt; 770 break; 771 } 772 } 773 774 /* Assumes that m is sane. */ 775 static int 776 ipsec6_setspidx_ipaddr(const struct mbuf *m, struct secpolicyindex *spidx) 777 { 778 struct ip6_hdr ip6buf; 779 const struct ip6_hdr *ip6 = NULL; 780 struct sockaddr_in6 *sin6; 781 782 if (m->m_len >= sizeof(*ip6)) 783 ip6 = mtod(m, const struct ip6_hdr *); 784 else { 785 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf); 786 ip6 = &ip6buf; 787 } 788 789 sin6 = (struct sockaddr_in6 *)&spidx->src; 790 bzero(sin6, sizeof(*sin6)); 791 sin6->sin6_family = AF_INET6; 792 sin6->sin6_len = sizeof(struct sockaddr_in6); 793 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src)); 794 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 795 sin6->sin6_addr.s6_addr16[1] = 0; 796 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 797 } 798 spidx->prefs = sizeof(struct in6_addr) << 3; 799 800 sin6 = (struct sockaddr_in6 *)&spidx->dst; 801 bzero(sin6, sizeof(*sin6)); 802 sin6->sin6_family = AF_INET6; 803 sin6->sin6_len = sizeof(struct sockaddr_in6); 804 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst)); 805 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 806 sin6->sin6_addr.s6_addr16[1] = 0; 807 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 808 } 809 spidx->prefd = sizeof(struct in6_addr) << 3; 810 811 return (0); 812 } 813 #endif 814 815 int 816 ipsec_run_hhooks(struct ipsec_ctx_data *ctx, int type) 817 { 818 int idx; 819 820 switch (ctx->af) { 821 #ifdef INET 822 case AF_INET: 823 idx = HHOOK_IPSEC_INET; 824 break; 825 #endif 826 #ifdef INET6 827 case AF_INET6: 828 idx = HHOOK_IPSEC_INET6; 829 break; 830 #endif 831 default: 832 return (EPFNOSUPPORT); 833 } 834 if (type == HHOOK_TYPE_IPSEC_IN) 835 HHOOKS_RUN_IF(V_ipsec_hhh_in[idx], ctx, NULL); 836 else 837 HHOOKS_RUN_IF(V_ipsec_hhh_out[idx], ctx, NULL); 838 if (*ctx->mp == NULL) 839 return (EACCES); 840 return (0); 841 } 842 843 static void 844 ipsec_delpcbpolicy(struct inpcbpolicy *p) 845 { 846 847 free(p, M_IPSEC_INPCB); 848 } 849 850 /* Initialize policy in PCB. */ 851 int 852 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp) 853 { 854 struct inpcbpolicy *new; 855 856 /* Sanity check. */ 857 if (so == NULL || pcb_sp == NULL) 858 panic("%s: NULL pointer was passed.\n", __func__); 859 860 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy), 861 M_IPSEC_INPCB, M_NOWAIT|M_ZERO); 862 if (new == NULL) { 863 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 864 return (ENOBUFS); 865 } 866 867 new->priv = IPSEC_IS_PRIVILEGED_SO(so); 868 869 if ((new->sp_in = KEY_NEWSP()) == NULL) { 870 ipsec_delpcbpolicy(new); 871 return (ENOBUFS); 872 } 873 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 874 if ((new->sp_out = KEY_NEWSP()) == NULL) { 875 KEY_FREESP(&new->sp_in); 876 ipsec_delpcbpolicy(new); 877 return (ENOBUFS); 878 } 879 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 880 *pcb_sp = new; 881 882 return (0); 883 } 884 885 /* Copy old IPsec policy into new. */ 886 int 887 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new) 888 { 889 struct secpolicy *sp; 890 891 sp = ipsec_deepcopy_policy(old->sp_in); 892 if (sp) { 893 KEY_FREESP(&new->sp_in); 894 new->sp_in = sp; 895 } else 896 return (ENOBUFS); 897 898 sp = ipsec_deepcopy_policy(old->sp_out); 899 if (sp) { 900 KEY_FREESP(&new->sp_out); 901 new->sp_out = sp; 902 } else 903 return (ENOBUFS); 904 905 new->priv = old->priv; 906 907 return (0); 908 } 909 910 struct ipsecrequest * 911 ipsec_newisr(void) 912 { 913 struct ipsecrequest *p; 914 915 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO); 916 if (p != NULL) 917 IPSECREQUEST_LOCK_INIT(p); 918 return (p); 919 } 920 921 void 922 ipsec_delisr(struct ipsecrequest *p) 923 { 924 925 IPSECREQUEST_LOCK_DESTROY(p); 926 free(p, M_IPSEC_SR); 927 } 928 929 /* Deep-copy a policy in PCB. */ 930 static struct secpolicy * 931 ipsec_deepcopy_policy(struct secpolicy *src) 932 { 933 struct ipsecrequest *newchain = NULL; 934 struct ipsecrequest *p; 935 struct ipsecrequest **q; 936 struct ipsecrequest *r; 937 struct secpolicy *dst; 938 939 if (src == NULL) 940 return (NULL); 941 dst = KEY_NEWSP(); 942 if (dst == NULL) 943 return (NULL); 944 945 /* 946 * Deep-copy IPsec request chain. This is required since struct 947 * ipsecrequest is not reference counted. 948 */ 949 q = &newchain; 950 for (p = src->req; p; p = p->next) { 951 *q = ipsec_newisr(); 952 if (*q == NULL) 953 goto fail; 954 (*q)->saidx.proto = p->saidx.proto; 955 (*q)->saidx.mode = p->saidx.mode; 956 (*q)->level = p->level; 957 (*q)->saidx.reqid = p->saidx.reqid; 958 959 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src)); 960 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst)); 961 962 (*q)->sp = dst; 963 964 q = &((*q)->next); 965 } 966 967 dst->req = newchain; 968 dst->policy = src->policy; 969 /* Do not touch the refcnt fields. */ 970 971 return (dst); 972 973 fail: 974 for (p = newchain; p; p = r) { 975 r = p->next; 976 ipsec_delisr(p); 977 p = NULL; 978 } 979 KEY_FREESP(&dst); 980 return (NULL); 981 } 982 983 /* Set policy and IPsec request if present. */ 984 static int 985 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname, 986 caddr_t request, size_t len, struct ucred *cred) 987 { 988 struct sadb_x_policy *xpl; 989 struct secpolicy *newsp = NULL; 990 int error; 991 992 /* Sanity check. */ 993 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL) 994 return (EINVAL); 995 if (len < sizeof(*xpl)) 996 return (EINVAL); 997 xpl = (struct sadb_x_policy *)request; 998 999 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1000 printf("%s: passed policy\n", __func__); 1001 kdebug_sadb_x_policy((struct sadb_ext *)xpl)); 1002 1003 /* Check policy type. */ 1004 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */ 1005 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 1006 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1007 return (EINVAL); 1008 1009 /* Check privileged socket. */ 1010 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1011 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0); 1012 if (error) 1013 return (EACCES); 1014 } 1015 1016 /* Allocating new SP entry. */ 1017 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1018 return (error); 1019 1020 /* Clear old SP and set new SP. */ 1021 KEY_FREESP(pcb_sp); 1022 *pcb_sp = newsp; 1023 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1024 printf("%s: new policy\n", __func__); 1025 kdebug_secpolicy(newsp)); 1026 1027 return (0); 1028 } 1029 1030 int 1031 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request, 1032 size_t len, struct ucred *cred) 1033 { 1034 struct sadb_x_policy *xpl; 1035 struct secpolicy **pcb_sp; 1036 1037 /* Sanity check. */ 1038 if (inp == NULL || request == NULL) 1039 return (EINVAL); 1040 if (len < sizeof(*xpl)) 1041 return (EINVAL); 1042 xpl = (struct sadb_x_policy *)request; 1043 1044 /* Select direction. */ 1045 switch (xpl->sadb_x_policy_dir) { 1046 case IPSEC_DIR_INBOUND: 1047 pcb_sp = &inp->inp_sp->sp_in; 1048 break; 1049 case IPSEC_DIR_OUTBOUND: 1050 pcb_sp = &inp->inp_sp->sp_out; 1051 break; 1052 default: 1053 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1054 xpl->sadb_x_policy_dir)); 1055 return (EINVAL); 1056 } 1057 1058 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred)); 1059 } 1060 1061 int 1062 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len, 1063 struct mbuf **mp) 1064 { 1065 struct sadb_x_policy *xpl; 1066 struct secpolicy *pcb_sp; 1067 1068 /* Sanity check. */ 1069 if (inp == NULL || request == NULL || mp == NULL) 1070 return (EINVAL); 1071 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 1072 if (len < sizeof(*xpl)) 1073 return (EINVAL); 1074 xpl = (struct sadb_x_policy *)request; 1075 1076 /* Select direction. */ 1077 switch (xpl->sadb_x_policy_dir) { 1078 case IPSEC_DIR_INBOUND: 1079 pcb_sp = inp->inp_sp->sp_in; 1080 break; 1081 case IPSEC_DIR_OUTBOUND: 1082 pcb_sp = inp->inp_sp->sp_out; 1083 break; 1084 default: 1085 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1086 xpl->sadb_x_policy_dir)); 1087 return (EINVAL); 1088 } 1089 1090 /* Sanity check. Should be an IPSEC_ASSERT. */ 1091 if (pcb_sp == NULL) 1092 return (EINVAL); 1093 1094 *mp = key_sp2msg(pcb_sp); 1095 if (!*mp) { 1096 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 1097 return (ENOBUFS); 1098 } 1099 1100 (*mp)->m_type = MT_DATA; 1101 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1102 printf("%s:\n", __func__); kdebug_mbuf(*mp)); 1103 1104 return (0); 1105 } 1106 1107 /* Delete policy in PCB. */ 1108 int 1109 ipsec_delete_pcbpolicy(struct inpcb *inp) 1110 { 1111 IPSEC_ASSERT(inp != NULL, ("null inp")); 1112 1113 if (inp->inp_sp == NULL) 1114 return (0); 1115 1116 if (inp->inp_sp->sp_in != NULL) 1117 KEY_FREESP(&inp->inp_sp->sp_in); 1118 1119 if (inp->inp_sp->sp_out != NULL) 1120 KEY_FREESP(&inp->inp_sp->sp_out); 1121 1122 ipsec_delpcbpolicy(inp->inp_sp); 1123 inp->inp_sp = NULL; 1124 1125 return (0); 1126 } 1127 1128 /* 1129 * Return current level. 1130 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1131 */ 1132 u_int 1133 ipsec_get_reqlevel(struct ipsecrequest *isr) 1134 { 1135 u_int level = 0; 1136 u_int esp_trans_deflev, esp_net_deflev; 1137 u_int ah_trans_deflev, ah_net_deflev; 1138 1139 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument")); 1140 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1141 ("af family mismatch, src %u, dst %u", 1142 isr->sp->spidx.src.sa.sa_family, 1143 isr->sp->spidx.dst.sa.sa_family)); 1144 1145 /* XXX Note that we have ipseclog() expanded here - code sync issue. */ 1146 #define IPSEC_CHECK_DEFAULT(lev) \ 1147 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1148 && (lev) != IPSEC_LEVEL_UNIQUE) \ 1149 ? (V_ipsec_debug \ 1150 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\ 1151 (lev), IPSEC_LEVEL_REQUIRE) \ 1152 : 0), \ 1153 (lev) = IPSEC_LEVEL_REQUIRE, \ 1154 (lev) \ 1155 : (lev)) 1156 1157 /* Set default level. */ 1158 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1159 #ifdef INET 1160 case AF_INET: 1161 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev); 1162 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev); 1163 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev); 1164 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev); 1165 break; 1166 #endif 1167 #ifdef INET6 1168 case AF_INET6: 1169 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev); 1170 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev); 1171 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev); 1172 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev); 1173 break; 1174 #endif /* INET6 */ 1175 default: 1176 panic("%s: unknown af %u", 1177 __func__, isr->sp->spidx.src.sa.sa_family); 1178 } 1179 1180 #undef IPSEC_CHECK_DEFAULT 1181 1182 /* Set level. */ 1183 switch (isr->level) { 1184 case IPSEC_LEVEL_DEFAULT: 1185 switch (isr->saidx.proto) { 1186 case IPPROTO_ESP: 1187 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1188 level = esp_net_deflev; 1189 else 1190 level = esp_trans_deflev; 1191 break; 1192 case IPPROTO_AH: 1193 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1194 level = ah_net_deflev; 1195 else 1196 level = ah_trans_deflev; 1197 break; 1198 case IPPROTO_IPCOMP: 1199 /* 1200 * We don't really care, as IPcomp document says that 1201 * we shouldn't compress small packets. 1202 */ 1203 level = IPSEC_LEVEL_USE; 1204 break; 1205 default: 1206 panic("%s: Illegal protocol defined %u\n", __func__, 1207 isr->saidx.proto); 1208 } 1209 break; 1210 1211 case IPSEC_LEVEL_USE: 1212 case IPSEC_LEVEL_REQUIRE: 1213 level = isr->level; 1214 break; 1215 case IPSEC_LEVEL_UNIQUE: 1216 level = IPSEC_LEVEL_REQUIRE; 1217 break; 1218 1219 default: 1220 panic("%s: Illegal IPsec level %u\n", __func__, isr->level); 1221 } 1222 1223 return (level); 1224 } 1225 1226 /* 1227 * Check security policy requirements against the actual 1228 * packet contents. Return one if the packet should be 1229 * reject as "invalid"; otherwiser return zero to have the 1230 * packet treated as "valid". 1231 * 1232 * OUT: 1233 * 0: valid 1234 * 1: invalid 1235 */ 1236 static int 1237 ipsec_in_reject(struct secpolicy *sp, const struct mbuf *m) 1238 { 1239 struct ipsecrequest *isr; 1240 int need_auth; 1241 1242 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1243 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1244 1245 /* Check policy. */ 1246 switch (sp->policy) { 1247 case IPSEC_POLICY_DISCARD: 1248 return (1); 1249 case IPSEC_POLICY_BYPASS: 1250 case IPSEC_POLICY_NONE: 1251 return (0); 1252 } 1253 1254 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1255 ("invalid policy %u", sp->policy)); 1256 1257 /* XXX Should compare policy against IPsec header history. */ 1258 1259 need_auth = 0; 1260 for (isr = sp->req; isr != NULL; isr = isr->next) { 1261 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1262 continue; 1263 switch (isr->saidx.proto) { 1264 case IPPROTO_ESP: 1265 if ((m->m_flags & M_DECRYPTED) == 0) { 1266 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1267 printf("%s: ESP m_flags:%x\n", __func__, 1268 m->m_flags)); 1269 return (1); 1270 } 1271 1272 if (!need_auth && 1273 isr->sav != NULL && 1274 isr->sav->tdb_authalgxform != NULL && 1275 (m->m_flags & M_AUTHIPDGM) == 0) { 1276 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1277 printf("%s: ESP/AH m_flags:%x\n", __func__, 1278 m->m_flags)); 1279 return (1); 1280 } 1281 break; 1282 case IPPROTO_AH: 1283 need_auth = 1; 1284 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1285 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1286 printf("%s: AH m_flags:%x\n", __func__, 1287 m->m_flags)); 1288 return (1); 1289 } 1290 break; 1291 case IPPROTO_IPCOMP: 1292 /* 1293 * We don't really care, as IPcomp document 1294 * says that we shouldn't compress small 1295 * packets. IPComp policy should always be 1296 * treated as being in "use" level. 1297 */ 1298 break; 1299 } 1300 } 1301 return (0); /* Valid. */ 1302 } 1303 1304 /* 1305 * Non zero return value means security policy DISCARD or policy violation. 1306 */ 1307 static int 1308 ipsec46_in_reject(const struct mbuf *m, struct inpcb *inp) 1309 { 1310 struct secpolicy *sp; 1311 int error; 1312 int result; 1313 1314 if (!key_havesp(IPSEC_DIR_INBOUND)) 1315 return 0; 1316 1317 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1318 1319 /* Get SP for this packet. */ 1320 if (inp == NULL) 1321 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, &error); 1322 else 1323 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error); 1324 1325 if (sp != NULL) { 1326 result = ipsec_in_reject(sp, m); 1327 KEY_FREESP(&sp); 1328 } else { 1329 result = 1; /* treat errors as policy violation */ 1330 } 1331 return (result); 1332 } 1333 1334 /* 1335 * Check AH/ESP integrity. 1336 * This function is called from tcp_input(), udp_input(), 1337 * and {ah,esp}4_input for tunnel mode. 1338 */ 1339 int 1340 ipsec4_in_reject(const struct mbuf *m, struct inpcb *inp) 1341 { 1342 int result; 1343 1344 result = ipsec46_in_reject(m, inp); 1345 if (result) 1346 IPSECSTAT_INC(ips_in_polvio); 1347 1348 return (result); 1349 } 1350 1351 #ifdef INET6 1352 /* 1353 * Check AH/ESP integrity. 1354 * This function is called from tcp6_input(), udp6_input(), 1355 * and {ah,esp}6_input for tunnel mode. 1356 */ 1357 int 1358 ipsec6_in_reject(const struct mbuf *m, struct inpcb *inp) 1359 { 1360 int result; 1361 1362 result = ipsec46_in_reject(m, inp); 1363 if (result) 1364 IPSEC6STAT_INC(ips_in_polvio); 1365 1366 return (result); 1367 } 1368 #endif 1369 1370 /* 1371 * Compute the byte size to be occupied by IPsec header. 1372 * In case it is tunnelled, it includes the size of outer IP header. 1373 * NOTE: SP passed is freed in this function. 1374 */ 1375 static size_t 1376 ipsec_hdrsiz_internal(struct secpolicy *sp) 1377 { 1378 struct ipsecrequest *isr; 1379 size_t size; 1380 1381 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1382 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1383 1384 switch (sp->policy) { 1385 case IPSEC_POLICY_DISCARD: 1386 case IPSEC_POLICY_BYPASS: 1387 case IPSEC_POLICY_NONE: 1388 return (0); 1389 } 1390 1391 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1392 ("invalid policy %u", sp->policy)); 1393 1394 size = 0; 1395 for (isr = sp->req; isr != NULL; isr = isr->next) { 1396 size_t clen = 0; 1397 1398 switch (isr->saidx.proto) { 1399 case IPPROTO_ESP: 1400 clen = esp_hdrsiz(isr->sav); 1401 break; 1402 case IPPROTO_AH: 1403 clen = ah_hdrsiz(isr->sav); 1404 break; 1405 case IPPROTO_IPCOMP: 1406 clen = sizeof(struct ipcomp); 1407 break; 1408 } 1409 1410 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1411 switch (isr->saidx.dst.sa.sa_family) { 1412 case AF_INET: 1413 clen += sizeof(struct ip); 1414 break; 1415 #ifdef INET6 1416 case AF_INET6: 1417 clen += sizeof(struct ip6_hdr); 1418 break; 1419 #endif 1420 default: 1421 ipseclog((LOG_ERR, "%s: unknown AF %d in " 1422 "IPsec tunnel SA\n", __func__, 1423 ((struct sockaddr *)&isr->saidx.dst)->sa_family)); 1424 break; 1425 } 1426 } 1427 size += clen; 1428 } 1429 1430 return (size); 1431 } 1432 1433 /* 1434 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(), 1435 * disabled ip6_ipsec_mtu() and ip6_forward(). 1436 */ 1437 size_t 1438 ipsec_hdrsiz(const struct mbuf *m, u_int dir, struct inpcb *inp) 1439 { 1440 struct secpolicy *sp; 1441 int error; 1442 size_t size; 1443 1444 if (!key_havesp(dir)) 1445 return 0; 1446 1447 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1448 1449 /* Get SP for this packet. */ 1450 if (inp == NULL) 1451 sp = ipsec_getpolicybyaddr(m, dir, &error); 1452 else 1453 sp = ipsec_getpolicybysock(m, dir, inp, &error); 1454 1455 if (sp != NULL) { 1456 size = ipsec_hdrsiz_internal(sp); 1457 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1458 printf("%s: size:%lu.\n", __func__, 1459 (unsigned long)size)); 1460 1461 KEY_FREESP(&sp); 1462 } else { 1463 size = 0; /* XXX Should be panic? 1464 * -> No, we are called w/o knowing if 1465 * IPsec processing is needed. */ 1466 } 1467 return (size); 1468 } 1469 1470 /* 1471 * Check the variable replay window. 1472 * ipsec_chkreplay() performs replay check before ICV verification. 1473 * ipsec_updatereplay() updates replay bitmap. This must be called after 1474 * ICV verification (it also performs replay check, which is usually done 1475 * beforehand). 1476 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1477 * 1478 * Based on RFC 6479. Blocks are 32 bits unsigned integers 1479 */ 1480 1481 #define IPSEC_BITMAP_INDEX_MASK(w) (w - 1) 1482 #define IPSEC_REDUNDANT_BIT_SHIFTS 5 1483 #define IPSEC_REDUNDANT_BITS (1 << IPSEC_REDUNDANT_BIT_SHIFTS) 1484 #define IPSEC_BITMAP_LOC_MASK (IPSEC_REDUNDANT_BITS - 1) 1485 1486 int 1487 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav) 1488 { 1489 const struct secreplay *replay; 1490 u_int32_t wsizeb; /* Constant: window size. */ 1491 int ret, index, bit_location; 1492 1493 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1494 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1495 1496 SECASVAR_LOCK(sav); 1497 1498 ret = 0; 1499 replay = sav->replay; 1500 1501 /* No need to check replay if disabled. */ 1502 if (replay->wsize == 0) 1503 goto allowed; 1504 1505 /* Constant. */ 1506 wsizeb = replay->wsize << 3; 1507 1508 /* Sequence number of 0 is invalid. */ 1509 if (seq == 0) 1510 goto end; 1511 1512 /* First time is always okay. */ 1513 if (replay->count == 0) 1514 goto allowed; 1515 1516 /* Larger sequences are okay. */ 1517 if (seq > replay->lastseq) 1518 goto allowed; 1519 1520 /* Over range to check, i.e. too old or wrapped. */ 1521 if (replay->lastseq - seq >= wsizeb) 1522 goto end; 1523 1524 /* The sequence is inside the sliding window 1525 * now check the bit in the bitmap 1526 * bit location only depends on the sequence number 1527 */ 1528 bit_location = seq & IPSEC_BITMAP_LOC_MASK; 1529 index = (seq >> IPSEC_REDUNDANT_BIT_SHIFTS) 1530 & IPSEC_BITMAP_INDEX_MASK(replay->bitmap_size); 1531 1532 /* This packet already seen? */ 1533 if ((replay->bitmap)[index] & (1 << bit_location)) 1534 goto end; 1535 1536 allowed: 1537 ret = 1; 1538 end: 1539 SECASVAR_UNLOCK(sav); 1540 1541 return (ret); 1542 } 1543 1544 /* 1545 * Check replay counter whether to update or not. 1546 * OUT: 0: OK 1547 * 1: NG 1548 */ 1549 int 1550 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav) 1551 { 1552 char buf[128]; 1553 struct secreplay *replay; 1554 u_int32_t wsizeb; /* Constant: window size. */ 1555 int ret, diff, index, bit_location; 1556 1557 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1558 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1559 1560 SECASVAR_LOCK(sav); 1561 1562 ret = 1; 1563 replay = sav->replay; 1564 1565 if (replay->wsize == 0) 1566 goto ok; /* No need to check replay. */ 1567 1568 /* Constant. */ 1569 wsizeb = replay->wsize << 3; 1570 1571 /* Sequence number of 0 is invalid. */ 1572 if (seq == 0) 1573 goto end; 1574 1575 /* The packet is too old, no need to update */ 1576 if (wsizeb + seq < replay->lastseq) 1577 goto ok; 1578 1579 /* Now update the bit */ 1580 index = (seq >> IPSEC_REDUNDANT_BIT_SHIFTS); 1581 1582 /* First check if the sequence number is in the range */ 1583 if (seq > replay->lastseq) { 1584 int id; 1585 int index_cur = replay->lastseq >> IPSEC_REDUNDANT_BIT_SHIFTS; 1586 1587 diff = index - index_cur; 1588 if (diff > replay->bitmap_size) { 1589 /* something unusual in this case */ 1590 diff = replay->bitmap_size; 1591 } 1592 1593 for (id = 0; id < diff; ++id) { 1594 replay->bitmap[(id + index_cur + 1) 1595 & IPSEC_BITMAP_INDEX_MASK(replay->bitmap_size)] = 0; 1596 } 1597 1598 replay->lastseq = seq; 1599 } 1600 1601 index &= IPSEC_BITMAP_INDEX_MASK(replay->bitmap_size); 1602 bit_location = seq & IPSEC_BITMAP_LOC_MASK; 1603 1604 /* this packet has already been received */ 1605 if (replay->bitmap[index] & (1 << bit_location)) 1606 goto end; 1607 1608 replay->bitmap[index] |= (1 << bit_location); 1609 1610 ok: 1611 if (replay->count == ~0) { 1612 1613 /* Set overflow flag. */ 1614 replay->overflow++; 1615 1616 /* Don't increment, no more packets accepted. */ 1617 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 1618 goto end; 1619 1620 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1621 __func__, replay->overflow, 1622 ipsec_logsastr(sav, buf, sizeof(buf)))); 1623 } 1624 1625 ret = 0; 1626 1627 end: 1628 SECASVAR_UNLOCK(sav); 1629 return (ret); 1630 } 1631 1632 /* Return a printable string for the address. */ 1633 char* 1634 ipsec_address(union sockaddr_union* sa, char *buf, socklen_t size) 1635 { 1636 1637 switch (sa->sa.sa_family) { 1638 #ifdef INET 1639 case AF_INET: 1640 return (inet_ntop(AF_INET, &sa->sin.sin_addr, buf, size)); 1641 #endif /* INET */ 1642 #ifdef INET6 1643 case AF_INET6: 1644 return (inet_ntop(AF_INET6, &sa->sin6.sin6_addr, buf, size)); 1645 #endif /* INET6 */ 1646 default: 1647 return ("(unknown address family)"); 1648 } 1649 } 1650 1651 char * 1652 ipsec_logsastr(struct secasvar *sav, char *buf, size_t size) 1653 { 1654 char sbuf[INET6_ADDRSTRLEN], dbuf[INET6_ADDRSTRLEN]; 1655 1656 IPSEC_ASSERT(sav->sah->saidx.src.sa.sa_family == 1657 sav->sah->saidx.dst.sa.sa_family, ("address family mismatch")); 1658 1659 snprintf(buf, size, "SA(SPI=%08lx src=%s dst=%s)", 1660 (u_long)ntohl(sav->spi), 1661 ipsec_address(&sav->sah->saidx.src, sbuf, sizeof(sbuf)), 1662 ipsec_address(&sav->sah->saidx.dst, dbuf, sizeof(dbuf))); 1663 return (buf); 1664 } 1665 1666 void 1667 ipsec_dumpmbuf(const struct mbuf *m) 1668 { 1669 const u_char *p; 1670 int totlen; 1671 int i; 1672 1673 totlen = 0; 1674 printf("---\n"); 1675 while (m) { 1676 p = mtod(m, const u_char *); 1677 for (i = 0; i < m->m_len; i++) { 1678 printf("%02x ", p[i]); 1679 totlen++; 1680 if (totlen % 16 == 0) 1681 printf("\n"); 1682 } 1683 m = m->m_next; 1684 } 1685 if (totlen % 16 != 0) 1686 printf("\n"); 1687 printf("---\n"); 1688 } 1689 1690 static void 1691 def_policy_init(const void *unused __unused) 1692 { 1693 1694 bzero(&V_def_policy, sizeof(struct secpolicy)); 1695 V_def_policy.policy = IPSEC_POLICY_NONE; 1696 V_def_policy.refcnt = 1; 1697 } 1698 VNET_SYSINIT(def_policy_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST, 1699 def_policy_init, NULL); 1700 1701 1702 /* XXX This stuff doesn't belong here... */ 1703 1704 static struct xformsw* xforms = NULL; 1705 1706 /* 1707 * Register a transform; typically at system startup. 1708 */ 1709 void 1710 xform_register(struct xformsw* xsp) 1711 { 1712 1713 xsp->xf_next = xforms; 1714 xforms = xsp; 1715 } 1716 1717 /* 1718 * Initialize transform support in an sav. 1719 */ 1720 int 1721 xform_init(struct secasvar *sav, int xftype) 1722 { 1723 struct xformsw *xsp; 1724 1725 if (sav->tdb_xform != NULL) /* Previously initialized. */ 1726 return (0); 1727 for (xsp = xforms; xsp; xsp = xsp->xf_next) 1728 if (xsp->xf_type == xftype) 1729 return ((*xsp->xf_init)(sav, xsp)); 1730 return (EINVAL); 1731 } 1732