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 static void vshiftl(unsigned char *, int, int); 255 256 MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy"); 257 258 /* 259 * Return a held reference to the default SP. 260 */ 261 static struct secpolicy * 262 key_allocsp_default(const char* where, int tag) 263 { 264 struct secpolicy *sp; 265 266 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 267 printf("DP key_allocsp_default from %s:%u\n", where, tag)); 268 269 sp = &V_def_policy; 270 if (sp->policy != IPSEC_POLICY_DISCARD && 271 sp->policy != IPSEC_POLICY_NONE) { 272 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n", 273 sp->policy, IPSEC_POLICY_NONE)); 274 sp->policy = IPSEC_POLICY_NONE; 275 } 276 key_addref(sp); 277 278 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 279 printf("DP key_allocsp_default returns SP:%p (%u)\n", 280 sp, sp->refcnt)); 281 return (sp); 282 } 283 #define KEY_ALLOCSP_DEFAULT() \ 284 key_allocsp_default(__FILE__, __LINE__) 285 286 /* 287 * For OUTBOUND packet having a socket. Searching SPD for packet, 288 * and return a pointer to SP. 289 * OUT: NULL: no apropreate SP found, the following value is set to error. 290 * 0 : bypass 291 * EACCES : discard packet. 292 * ENOENT : ipsec_acquire() in progress, maybe. 293 * others : error occurred. 294 * others: a pointer to SP 295 * 296 * NOTE: IPv6 mapped adddress concern is implemented here. 297 */ 298 struct secpolicy * 299 ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir) 300 { 301 struct secpolicy *sp; 302 303 IPSEC_ASSERT(tdbi != NULL, ("null tdbi")); 304 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 305 ("invalid direction %u", dir)); 306 307 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir); 308 if (sp == NULL) /*XXX????*/ 309 sp = KEY_ALLOCSP_DEFAULT(); 310 IPSEC_ASSERT(sp != NULL, ("null SP")); 311 return (sp); 312 } 313 314 /* 315 * For OUTBOUND packet having a socket. Searching SPD for packet, 316 * and return a pointer to SP. 317 * OUT: NULL: no apropreate SP found, the following value is set to error. 318 * 0 : bypass 319 * EACCES : discard packet. 320 * ENOENT : ipsec_acquire() in progress, maybe. 321 * others : error occurred. 322 * others: a pointer to SP 323 * 324 * NOTE: IPv6 mapped adddress concern is implemented here. 325 */ 326 static struct secpolicy * 327 ipsec_getpolicybysock(const struct mbuf *m, u_int dir, struct inpcb *inp, 328 int *error) 329 { 330 struct inpcbpolicy *pcbsp; 331 struct secpolicy *currsp = NULL; /* Policy on socket. */ 332 struct secpolicy *sp; 333 334 IPSEC_ASSERT(m != NULL, ("null mbuf")); 335 IPSEC_ASSERT(inp != NULL, ("null inpcb")); 336 IPSEC_ASSERT(error != NULL, ("null error")); 337 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 338 ("invalid direction %u", dir)); 339 340 if (!key_havesp(dir)) { 341 /* No SP found, use system default. */ 342 sp = KEY_ALLOCSP_DEFAULT(); 343 return (sp); 344 } 345 346 /* Set spidx in pcb. */ 347 *error = ipsec_setspidx_inpcb(m, inp); 348 if (*error) 349 return (NULL); 350 351 pcbsp = inp->inp_sp; 352 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp")); 353 switch (dir) { 354 case IPSEC_DIR_INBOUND: 355 currsp = pcbsp->sp_in; 356 break; 357 case IPSEC_DIR_OUTBOUND: 358 currsp = pcbsp->sp_out; 359 break; 360 } 361 IPSEC_ASSERT(currsp != NULL, ("null currsp")); 362 363 if (pcbsp->priv) { /* When privilieged socket. */ 364 switch (currsp->policy) { 365 case IPSEC_POLICY_BYPASS: 366 case IPSEC_POLICY_IPSEC: 367 key_addref(currsp); 368 sp = currsp; 369 break; 370 371 case IPSEC_POLICY_ENTRUST: 372 /* Look for a policy in SPD. */ 373 sp = KEY_ALLOCSP(&currsp->spidx, dir); 374 if (sp == NULL) /* No SP found. */ 375 sp = KEY_ALLOCSP_DEFAULT(); 376 break; 377 378 default: 379 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n", 380 __func__, currsp->policy)); 381 *error = EINVAL; 382 return (NULL); 383 } 384 } else { /* Unpriv, SPD has policy. */ 385 sp = KEY_ALLOCSP(&currsp->spidx, dir); 386 if (sp == NULL) { /* No SP found. */ 387 switch (currsp->policy) { 388 case IPSEC_POLICY_BYPASS: 389 ipseclog((LOG_ERR, "%s: Illegal policy for " 390 "non-priviliged defined %d\n", 391 __func__, currsp->policy)); 392 *error = EINVAL; 393 return (NULL); 394 395 case IPSEC_POLICY_ENTRUST: 396 sp = KEY_ALLOCSP_DEFAULT(); 397 break; 398 399 case IPSEC_POLICY_IPSEC: 400 key_addref(currsp); 401 sp = currsp; 402 break; 403 404 default: 405 ipseclog((LOG_ERR, "%s: Invalid policy for " 406 "PCB %d\n", __func__, currsp->policy)); 407 *error = EINVAL; 408 return (NULL); 409 } 410 } 411 } 412 IPSEC_ASSERT(sp != NULL, 413 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy)); 414 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 415 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n", 416 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt)); 417 return (sp); 418 } 419 420 /* 421 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 422 * and return a pointer to SP. 423 * OUT: positive: a pointer to the entry for security policy leaf matched. 424 * NULL: no apropreate SP found, the following value is set to error. 425 * 0 : bypass 426 * EACCES : discard packet. 427 * ENOENT : ipsec_acquire() in progress, maybe. 428 * others : error occurred. 429 */ 430 struct secpolicy * 431 ipsec_getpolicybyaddr(const struct mbuf *m, u_int dir, int *error) 432 { 433 struct secpolicyindex spidx; 434 struct secpolicy *sp; 435 436 IPSEC_ASSERT(m != NULL, ("null mbuf")); 437 IPSEC_ASSERT(error != NULL, ("null error")); 438 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 439 ("invalid direction %u", dir)); 440 441 sp = NULL; 442 *error = 0; 443 if (key_havesp(dir)) { 444 /* Make an index to look for a policy. */ 445 *error = ipsec_setspidx(m, &spidx, 0); 446 if (*error != 0) { 447 DPRINTF(("%s: setpidx failed, dir %u\n", 448 __func__, dir)); 449 return (NULL); 450 } 451 spidx.dir = dir; 452 sp = KEY_ALLOCSP(&spidx, dir); 453 } 454 if (sp == NULL) /* No SP found, use system default. */ 455 sp = KEY_ALLOCSP_DEFAULT(); 456 IPSEC_ASSERT(sp != NULL, ("null SP")); 457 return (sp); 458 } 459 460 struct secpolicy * 461 ipsec4_checkpolicy(const struct mbuf *m, u_int dir, int *error, 462 struct inpcb *inp) 463 { 464 struct secpolicy *sp; 465 466 *error = 0; 467 if (inp == NULL) 468 sp = ipsec_getpolicybyaddr(m, dir, error); 469 else 470 sp = ipsec_getpolicybysock(m, dir, inp, error); 471 if (sp == NULL) { 472 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error")); 473 IPSECSTAT_INC(ips_out_inval); 474 return (NULL); 475 } 476 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error)); 477 switch (sp->policy) { 478 case IPSEC_POLICY_ENTRUST: 479 default: 480 printf("%s: invalid policy %u\n", __func__, sp->policy); 481 /* FALLTHROUGH */ 482 case IPSEC_POLICY_DISCARD: 483 IPSECSTAT_INC(ips_out_polvio); 484 *error = -EINVAL; /* Packet is discarded by caller. */ 485 break; 486 case IPSEC_POLICY_BYPASS: 487 case IPSEC_POLICY_NONE: 488 KEY_FREESP(&sp); 489 sp = NULL; /* NB: force NULL result. */ 490 break; 491 case IPSEC_POLICY_IPSEC: 492 if (sp->req == NULL) /* Acquire a SA. */ 493 *error = key_spdacquire(sp); 494 break; 495 } 496 if (*error != 0) { 497 KEY_FREESP(&sp); 498 sp = NULL; 499 } 500 return (sp); 501 } 502 503 static int 504 ipsec_setspidx_inpcb(const struct mbuf *m, struct inpcb *inp) 505 { 506 int error; 507 508 IPSEC_ASSERT(inp != NULL, ("null inp")); 509 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 510 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL, 511 ("null sp_in || sp_out")); 512 513 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1); 514 if (error == 0) { 515 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 516 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx; 517 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 518 } else { 519 bzero(&inp->inp_sp->sp_in->spidx, 520 sizeof (inp->inp_sp->sp_in->spidx)); 521 bzero(&inp->inp_sp->sp_out->spidx, 522 sizeof (inp->inp_sp->sp_in->spidx)); 523 } 524 return (error); 525 } 526 527 /* 528 * Configure security policy index (src/dst/proto/sport/dport) 529 * by looking at the content of mbuf. 530 * The caller is responsible for error recovery (like clearing up spidx). 531 */ 532 static int 533 ipsec_setspidx(const struct mbuf *m, struct secpolicyindex *spidx, 534 int needport) 535 { 536 struct ip ipbuf; 537 const struct ip *ip = NULL; 538 const struct mbuf *n; 539 u_int v; 540 int len; 541 int error; 542 543 IPSEC_ASSERT(m != NULL, ("null mbuf")); 544 545 /* 546 * Validate m->m_pkthdr.len. We see incorrect length if we 547 * mistakenly call this function with inconsistent mbuf chain 548 * (like 4.4BSD tcp/udp processing). XXX Should we panic here? 549 */ 550 len = 0; 551 for (n = m; n; n = n->m_next) 552 len += n->m_len; 553 if (m->m_pkthdr.len != len) { 554 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 555 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n", 556 __func__, len, m->m_pkthdr.len)); 557 return (EINVAL); 558 } 559 560 if (m->m_pkthdr.len < sizeof(struct ip)) { 561 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 562 printf("%s: pkthdr len(%d) too small (v4), ignored.\n", 563 __func__, m->m_pkthdr.len)); 564 return (EINVAL); 565 } 566 567 if (m->m_len >= sizeof(*ip)) 568 ip = mtod(m, const struct ip *); 569 else { 570 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf); 571 ip = &ipbuf; 572 } 573 v = ip->ip_v; 574 switch (v) { 575 case 4: 576 error = ipsec4_setspidx_ipaddr(m, spidx); 577 if (error) 578 return (error); 579 ipsec4_get_ulp(m, spidx, needport); 580 return (0); 581 #ifdef INET6 582 case 6: 583 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 584 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 585 printf("%s: pkthdr len(%d) too small (v6), " 586 "ignored\n", __func__, m->m_pkthdr.len)); 587 return (EINVAL); 588 } 589 error = ipsec6_setspidx_ipaddr(m, spidx); 590 if (error) 591 return (error); 592 ipsec6_get_ulp(m, spidx, needport); 593 return (0); 594 #endif 595 default: 596 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 597 printf("%s: " "unknown IP version %u, ignored.\n", 598 __func__, v)); 599 return (EINVAL); 600 } 601 } 602 603 static void 604 ipsec4_get_ulp(const struct mbuf *m, struct secpolicyindex *spidx, 605 int needport) 606 { 607 u_int8_t nxt; 608 int off; 609 610 /* Sanity check. */ 611 IPSEC_ASSERT(m != NULL, ("null mbuf")); 612 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short")); 613 614 if (m->m_len >= sizeof (struct ip)) { 615 const struct ip *ip = mtod(m, const struct ip *); 616 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 617 goto done; 618 off = ip->ip_hl << 2; 619 nxt = ip->ip_p; 620 } else { 621 struct ip ih; 622 623 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih); 624 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 625 goto done; 626 off = ih.ip_hl << 2; 627 nxt = ih.ip_p; 628 } 629 630 while (off < m->m_pkthdr.len) { 631 struct ip6_ext ip6e; 632 struct tcphdr th; 633 struct udphdr uh; 634 635 switch (nxt) { 636 case IPPROTO_TCP: 637 spidx->ul_proto = nxt; 638 if (!needport) 639 goto done_proto; 640 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 641 goto done; 642 m_copydata(m, off, sizeof (th), (caddr_t) &th); 643 spidx->src.sin.sin_port = th.th_sport; 644 spidx->dst.sin.sin_port = th.th_dport; 645 return; 646 case IPPROTO_UDP: 647 spidx->ul_proto = nxt; 648 if (!needport) 649 goto done_proto; 650 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 651 goto done; 652 m_copydata(m, off, sizeof (uh), (caddr_t) &uh); 653 spidx->src.sin.sin_port = uh.uh_sport; 654 spidx->dst.sin.sin_port = uh.uh_dport; 655 return; 656 case IPPROTO_AH: 657 if (off + sizeof(ip6e) > m->m_pkthdr.len) 658 goto done; 659 /* XXX Sigh, this works but is totally bogus. */ 660 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e); 661 off += (ip6e.ip6e_len + 2) << 2; 662 nxt = ip6e.ip6e_nxt; 663 break; 664 case IPPROTO_ICMP: 665 default: 666 /* XXX Intermediate headers??? */ 667 spidx->ul_proto = nxt; 668 goto done_proto; 669 } 670 } 671 done: 672 spidx->ul_proto = IPSEC_ULPROTO_ANY; 673 done_proto: 674 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 675 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 676 } 677 678 /* Assumes that m is sane. */ 679 static int 680 ipsec4_setspidx_ipaddr(const struct mbuf *m, struct secpolicyindex *spidx) 681 { 682 static const struct sockaddr_in template = { 683 sizeof (struct sockaddr_in), 684 AF_INET, 685 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 686 }; 687 688 spidx->src.sin = template; 689 spidx->dst.sin = template; 690 691 if (m->m_len < sizeof (struct ip)) { 692 m_copydata(m, offsetof(struct ip, ip_src), 693 sizeof (struct in_addr), 694 (caddr_t) &spidx->src.sin.sin_addr); 695 m_copydata(m, offsetof(struct ip, ip_dst), 696 sizeof (struct in_addr), 697 (caddr_t) &spidx->dst.sin.sin_addr); 698 } else { 699 const struct ip *ip = mtod(m, const struct ip *); 700 spidx->src.sin.sin_addr = ip->ip_src; 701 spidx->dst.sin.sin_addr = ip->ip_dst; 702 } 703 704 spidx->prefs = sizeof(struct in_addr) << 3; 705 spidx->prefd = sizeof(struct in_addr) << 3; 706 707 return (0); 708 } 709 710 #ifdef INET6 711 static void 712 ipsec6_get_ulp(const struct mbuf *m, struct secpolicyindex *spidx, 713 int needport) 714 { 715 int off, nxt; 716 struct tcphdr th; 717 struct udphdr uh; 718 struct icmp6_hdr ih; 719 720 /* Sanity check. */ 721 if (m == NULL) 722 panic("%s: NULL pointer was passed.\n", __func__); 723 724 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 725 printf("%s:\n", __func__); kdebug_mbuf(m)); 726 727 /* Set default. */ 728 spidx->ul_proto = IPSEC_ULPROTO_ANY; 729 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 730 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 731 732 nxt = -1; 733 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 734 if (off < 0 || m->m_pkthdr.len < off) 735 return; 736 737 switch (nxt) { 738 case IPPROTO_TCP: 739 spidx->ul_proto = nxt; 740 if (!needport) 741 break; 742 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 743 break; 744 m_copydata(m, off, sizeof(th), (caddr_t)&th); 745 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 746 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 747 break; 748 case IPPROTO_UDP: 749 spidx->ul_proto = nxt; 750 if (!needport) 751 break; 752 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 753 break; 754 m_copydata(m, off, sizeof(uh), (caddr_t)&uh); 755 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 756 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 757 break; 758 case IPPROTO_ICMPV6: 759 spidx->ul_proto = nxt; 760 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 761 break; 762 m_copydata(m, off, sizeof(ih), (caddr_t)&ih); 763 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 764 htons((uint16_t)ih.icmp6_type); 765 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 766 htons((uint16_t)ih.icmp6_code); 767 break; 768 default: 769 /* XXX Intermediate headers??? */ 770 spidx->ul_proto = nxt; 771 break; 772 } 773 } 774 775 /* Assumes that m is sane. */ 776 static int 777 ipsec6_setspidx_ipaddr(const struct mbuf *m, struct secpolicyindex *spidx) 778 { 779 struct ip6_hdr ip6buf; 780 const struct ip6_hdr *ip6 = NULL; 781 struct sockaddr_in6 *sin6; 782 783 if (m->m_len >= sizeof(*ip6)) 784 ip6 = mtod(m, const struct ip6_hdr *); 785 else { 786 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf); 787 ip6 = &ip6buf; 788 } 789 790 sin6 = (struct sockaddr_in6 *)&spidx->src; 791 bzero(sin6, sizeof(*sin6)); 792 sin6->sin6_family = AF_INET6; 793 sin6->sin6_len = sizeof(struct sockaddr_in6); 794 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src)); 795 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 796 sin6->sin6_addr.s6_addr16[1] = 0; 797 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 798 } 799 spidx->prefs = sizeof(struct in6_addr) << 3; 800 801 sin6 = (struct sockaddr_in6 *)&spidx->dst; 802 bzero(sin6, sizeof(*sin6)); 803 sin6->sin6_family = AF_INET6; 804 sin6->sin6_len = sizeof(struct sockaddr_in6); 805 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst)); 806 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 807 sin6->sin6_addr.s6_addr16[1] = 0; 808 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 809 } 810 spidx->prefd = sizeof(struct in6_addr) << 3; 811 812 return (0); 813 } 814 #endif 815 816 int 817 ipsec_run_hhooks(struct ipsec_ctx_data *ctx, int type) 818 { 819 int idx; 820 821 switch (ctx->af) { 822 #ifdef INET 823 case AF_INET: 824 idx = HHOOK_IPSEC_INET; 825 break; 826 #endif 827 #ifdef INET6 828 case AF_INET6: 829 idx = HHOOK_IPSEC_INET6; 830 break; 831 #endif 832 default: 833 return (EPFNOSUPPORT); 834 } 835 if (type == HHOOK_TYPE_IPSEC_IN) 836 HHOOKS_RUN_IF(V_ipsec_hhh_in[idx], ctx, NULL); 837 else 838 HHOOKS_RUN_IF(V_ipsec_hhh_out[idx], ctx, NULL); 839 if (*ctx->mp == NULL) 840 return (EACCES); 841 return (0); 842 } 843 844 static void 845 ipsec_delpcbpolicy(struct inpcbpolicy *p) 846 { 847 848 free(p, M_IPSEC_INPCB); 849 } 850 851 /* Initialize policy in PCB. */ 852 int 853 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp) 854 { 855 struct inpcbpolicy *new; 856 857 /* Sanity check. */ 858 if (so == NULL || pcb_sp == NULL) 859 panic("%s: NULL pointer was passed.\n", __func__); 860 861 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy), 862 M_IPSEC_INPCB, M_NOWAIT|M_ZERO); 863 if (new == NULL) { 864 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 865 return (ENOBUFS); 866 } 867 868 new->priv = IPSEC_IS_PRIVILEGED_SO(so); 869 870 if ((new->sp_in = KEY_NEWSP()) == NULL) { 871 ipsec_delpcbpolicy(new); 872 return (ENOBUFS); 873 } 874 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 875 if ((new->sp_out = KEY_NEWSP()) == NULL) { 876 KEY_FREESP(&new->sp_in); 877 ipsec_delpcbpolicy(new); 878 return (ENOBUFS); 879 } 880 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 881 *pcb_sp = new; 882 883 return (0); 884 } 885 886 /* Copy old IPsec policy into new. */ 887 int 888 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new) 889 { 890 struct secpolicy *sp; 891 892 sp = ipsec_deepcopy_policy(old->sp_in); 893 if (sp) { 894 KEY_FREESP(&new->sp_in); 895 new->sp_in = sp; 896 } else 897 return (ENOBUFS); 898 899 sp = ipsec_deepcopy_policy(old->sp_out); 900 if (sp) { 901 KEY_FREESP(&new->sp_out); 902 new->sp_out = sp; 903 } else 904 return (ENOBUFS); 905 906 new->priv = old->priv; 907 908 return (0); 909 } 910 911 struct ipsecrequest * 912 ipsec_newisr(void) 913 { 914 struct ipsecrequest *p; 915 916 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO); 917 if (p != NULL) 918 IPSECREQUEST_LOCK_INIT(p); 919 return (p); 920 } 921 922 void 923 ipsec_delisr(struct ipsecrequest *p) 924 { 925 926 IPSECREQUEST_LOCK_DESTROY(p); 927 free(p, M_IPSEC_SR); 928 } 929 930 /* Deep-copy a policy in PCB. */ 931 static struct secpolicy * 932 ipsec_deepcopy_policy(struct secpolicy *src) 933 { 934 struct ipsecrequest *newchain = NULL; 935 struct ipsecrequest *p; 936 struct ipsecrequest **q; 937 struct ipsecrequest *r; 938 struct secpolicy *dst; 939 940 if (src == NULL) 941 return (NULL); 942 dst = KEY_NEWSP(); 943 if (dst == NULL) 944 return (NULL); 945 946 /* 947 * Deep-copy IPsec request chain. This is required since struct 948 * ipsecrequest is not reference counted. 949 */ 950 q = &newchain; 951 for (p = src->req; p; p = p->next) { 952 *q = ipsec_newisr(); 953 if (*q == NULL) 954 goto fail; 955 (*q)->saidx.proto = p->saidx.proto; 956 (*q)->saidx.mode = p->saidx.mode; 957 (*q)->level = p->level; 958 (*q)->saidx.reqid = p->saidx.reqid; 959 960 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src)); 961 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst)); 962 963 (*q)->sp = dst; 964 965 q = &((*q)->next); 966 } 967 968 dst->req = newchain; 969 dst->policy = src->policy; 970 /* Do not touch the refcnt fields. */ 971 972 return (dst); 973 974 fail: 975 for (p = newchain; p; p = r) { 976 r = p->next; 977 ipsec_delisr(p); 978 p = NULL; 979 } 980 KEY_FREESP(&dst); 981 return (NULL); 982 } 983 984 /* Set policy and IPsec request if present. */ 985 static int 986 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname, 987 caddr_t request, size_t len, struct ucred *cred) 988 { 989 struct sadb_x_policy *xpl; 990 struct secpolicy *newsp = NULL; 991 int error; 992 993 /* Sanity check. */ 994 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL) 995 return (EINVAL); 996 if (len < sizeof(*xpl)) 997 return (EINVAL); 998 xpl = (struct sadb_x_policy *)request; 999 1000 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1001 printf("%s: passed policy\n", __func__); 1002 kdebug_sadb_x_policy((struct sadb_ext *)xpl)); 1003 1004 /* Check policy type. */ 1005 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */ 1006 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 1007 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1008 return (EINVAL); 1009 1010 /* Check privileged socket. */ 1011 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1012 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0); 1013 if (error) 1014 return (EACCES); 1015 } 1016 1017 /* Allocating new SP entry. */ 1018 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1019 return (error); 1020 1021 /* Clear old SP and set new SP. */ 1022 KEY_FREESP(pcb_sp); 1023 *pcb_sp = newsp; 1024 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1025 printf("%s: new policy\n", __func__); 1026 kdebug_secpolicy(newsp)); 1027 1028 return (0); 1029 } 1030 1031 int 1032 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request, 1033 size_t len, struct ucred *cred) 1034 { 1035 struct sadb_x_policy *xpl; 1036 struct secpolicy **pcb_sp; 1037 1038 /* Sanity check. */ 1039 if (inp == NULL || request == NULL) 1040 return (EINVAL); 1041 if (len < sizeof(*xpl)) 1042 return (EINVAL); 1043 xpl = (struct sadb_x_policy *)request; 1044 1045 /* Select direction. */ 1046 switch (xpl->sadb_x_policy_dir) { 1047 case IPSEC_DIR_INBOUND: 1048 pcb_sp = &inp->inp_sp->sp_in; 1049 break; 1050 case IPSEC_DIR_OUTBOUND: 1051 pcb_sp = &inp->inp_sp->sp_out; 1052 break; 1053 default: 1054 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1055 xpl->sadb_x_policy_dir)); 1056 return (EINVAL); 1057 } 1058 1059 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred)); 1060 } 1061 1062 int 1063 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len, 1064 struct mbuf **mp) 1065 { 1066 struct sadb_x_policy *xpl; 1067 struct secpolicy *pcb_sp; 1068 1069 /* Sanity check. */ 1070 if (inp == NULL || request == NULL || mp == NULL) 1071 return (EINVAL); 1072 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 1073 if (len < sizeof(*xpl)) 1074 return (EINVAL); 1075 xpl = (struct sadb_x_policy *)request; 1076 1077 /* Select direction. */ 1078 switch (xpl->sadb_x_policy_dir) { 1079 case IPSEC_DIR_INBOUND: 1080 pcb_sp = inp->inp_sp->sp_in; 1081 break; 1082 case IPSEC_DIR_OUTBOUND: 1083 pcb_sp = inp->inp_sp->sp_out; 1084 break; 1085 default: 1086 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1087 xpl->sadb_x_policy_dir)); 1088 return (EINVAL); 1089 } 1090 1091 /* Sanity check. Should be an IPSEC_ASSERT. */ 1092 if (pcb_sp == NULL) 1093 return (EINVAL); 1094 1095 *mp = key_sp2msg(pcb_sp); 1096 if (!*mp) { 1097 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 1098 return (ENOBUFS); 1099 } 1100 1101 (*mp)->m_type = MT_DATA; 1102 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1103 printf("%s:\n", __func__); kdebug_mbuf(*mp)); 1104 1105 return (0); 1106 } 1107 1108 /* Delete policy in PCB. */ 1109 int 1110 ipsec_delete_pcbpolicy(struct inpcb *inp) 1111 { 1112 IPSEC_ASSERT(inp != NULL, ("null inp")); 1113 1114 if (inp->inp_sp == NULL) 1115 return (0); 1116 1117 if (inp->inp_sp->sp_in != NULL) 1118 KEY_FREESP(&inp->inp_sp->sp_in); 1119 1120 if (inp->inp_sp->sp_out != NULL) 1121 KEY_FREESP(&inp->inp_sp->sp_out); 1122 1123 ipsec_delpcbpolicy(inp->inp_sp); 1124 inp->inp_sp = NULL; 1125 1126 return (0); 1127 } 1128 1129 /* 1130 * Return current level. 1131 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1132 */ 1133 u_int 1134 ipsec_get_reqlevel(struct ipsecrequest *isr) 1135 { 1136 u_int level = 0; 1137 u_int esp_trans_deflev, esp_net_deflev; 1138 u_int ah_trans_deflev, ah_net_deflev; 1139 1140 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument")); 1141 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1142 ("af family mismatch, src %u, dst %u", 1143 isr->sp->spidx.src.sa.sa_family, 1144 isr->sp->spidx.dst.sa.sa_family)); 1145 1146 /* XXX Note that we have ipseclog() expanded here - code sync issue. */ 1147 #define IPSEC_CHECK_DEFAULT(lev) \ 1148 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1149 && (lev) != IPSEC_LEVEL_UNIQUE) \ 1150 ? (V_ipsec_debug \ 1151 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\ 1152 (lev), IPSEC_LEVEL_REQUIRE) \ 1153 : 0), \ 1154 (lev) = IPSEC_LEVEL_REQUIRE, \ 1155 (lev) \ 1156 : (lev)) 1157 1158 /* Set default level. */ 1159 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1160 #ifdef INET 1161 case AF_INET: 1162 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev); 1163 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev); 1164 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev); 1165 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev); 1166 break; 1167 #endif 1168 #ifdef INET6 1169 case AF_INET6: 1170 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev); 1171 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev); 1172 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev); 1173 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev); 1174 break; 1175 #endif /* INET6 */ 1176 default: 1177 panic("%s: unknown af %u", 1178 __func__, isr->sp->spidx.src.sa.sa_family); 1179 } 1180 1181 #undef IPSEC_CHECK_DEFAULT 1182 1183 /* Set level. */ 1184 switch (isr->level) { 1185 case IPSEC_LEVEL_DEFAULT: 1186 switch (isr->saidx.proto) { 1187 case IPPROTO_ESP: 1188 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1189 level = esp_net_deflev; 1190 else 1191 level = esp_trans_deflev; 1192 break; 1193 case IPPROTO_AH: 1194 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1195 level = ah_net_deflev; 1196 else 1197 level = ah_trans_deflev; 1198 break; 1199 case IPPROTO_IPCOMP: 1200 /* 1201 * We don't really care, as IPcomp document says that 1202 * we shouldn't compress small packets. 1203 */ 1204 level = IPSEC_LEVEL_USE; 1205 break; 1206 default: 1207 panic("%s: Illegal protocol defined %u\n", __func__, 1208 isr->saidx.proto); 1209 } 1210 break; 1211 1212 case IPSEC_LEVEL_USE: 1213 case IPSEC_LEVEL_REQUIRE: 1214 level = isr->level; 1215 break; 1216 case IPSEC_LEVEL_UNIQUE: 1217 level = IPSEC_LEVEL_REQUIRE; 1218 break; 1219 1220 default: 1221 panic("%s: Illegal IPsec level %u\n", __func__, isr->level); 1222 } 1223 1224 return (level); 1225 } 1226 1227 /* 1228 * Check security policy requirements against the actual 1229 * packet contents. Return one if the packet should be 1230 * reject as "invalid"; otherwiser return zero to have the 1231 * packet treated as "valid". 1232 * 1233 * OUT: 1234 * 0: valid 1235 * 1: invalid 1236 */ 1237 static int 1238 ipsec_in_reject(struct secpolicy *sp, const struct mbuf *m) 1239 { 1240 struct ipsecrequest *isr; 1241 int need_auth; 1242 1243 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1244 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1245 1246 /* Check policy. */ 1247 switch (sp->policy) { 1248 case IPSEC_POLICY_DISCARD: 1249 return (1); 1250 case IPSEC_POLICY_BYPASS: 1251 case IPSEC_POLICY_NONE: 1252 return (0); 1253 } 1254 1255 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1256 ("invalid policy %u", sp->policy)); 1257 1258 /* XXX Should compare policy against IPsec header history. */ 1259 1260 need_auth = 0; 1261 for (isr = sp->req; isr != NULL; isr = isr->next) { 1262 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1263 continue; 1264 switch (isr->saidx.proto) { 1265 case IPPROTO_ESP: 1266 if ((m->m_flags & M_DECRYPTED) == 0) { 1267 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1268 printf("%s: ESP m_flags:%x\n", __func__, 1269 m->m_flags)); 1270 return (1); 1271 } 1272 1273 if (!need_auth && 1274 isr->sav != NULL && 1275 isr->sav->tdb_authalgxform != NULL && 1276 (m->m_flags & M_AUTHIPDGM) == 0) { 1277 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1278 printf("%s: ESP/AH m_flags:%x\n", __func__, 1279 m->m_flags)); 1280 return (1); 1281 } 1282 break; 1283 case IPPROTO_AH: 1284 need_auth = 1; 1285 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1286 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1287 printf("%s: AH m_flags:%x\n", __func__, 1288 m->m_flags)); 1289 return (1); 1290 } 1291 break; 1292 case IPPROTO_IPCOMP: 1293 /* 1294 * We don't really care, as IPcomp document 1295 * says that we shouldn't compress small 1296 * packets. IPComp policy should always be 1297 * treated as being in "use" level. 1298 */ 1299 break; 1300 } 1301 } 1302 return (0); /* Valid. */ 1303 } 1304 1305 /* 1306 * Non zero return value means security policy DISCARD or policy violation. 1307 */ 1308 static int 1309 ipsec46_in_reject(const struct mbuf *m, struct inpcb *inp) 1310 { 1311 struct secpolicy *sp; 1312 int error; 1313 int result; 1314 1315 if (!key_havesp(IPSEC_DIR_INBOUND)) 1316 return 0; 1317 1318 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1319 1320 /* Get SP for this packet. */ 1321 if (inp == NULL) 1322 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, &error); 1323 else 1324 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error); 1325 1326 if (sp != NULL) { 1327 result = ipsec_in_reject(sp, m); 1328 KEY_FREESP(&sp); 1329 } else { 1330 result = 1; /* treat errors as policy violation */ 1331 } 1332 return (result); 1333 } 1334 1335 /* 1336 * Check AH/ESP integrity. 1337 * This function is called from tcp_input(), udp_input(), 1338 * and {ah,esp}4_input for tunnel mode. 1339 */ 1340 int 1341 ipsec4_in_reject(const struct mbuf *m, struct inpcb *inp) 1342 { 1343 int result; 1344 1345 result = ipsec46_in_reject(m, inp); 1346 if (result) 1347 IPSECSTAT_INC(ips_in_polvio); 1348 1349 return (result); 1350 } 1351 1352 #ifdef INET6 1353 /* 1354 * Check AH/ESP integrity. 1355 * This function is called from tcp6_input(), udp6_input(), 1356 * and {ah,esp}6_input for tunnel mode. 1357 */ 1358 int 1359 ipsec6_in_reject(const struct mbuf *m, struct inpcb *inp) 1360 { 1361 int result; 1362 1363 result = ipsec46_in_reject(m, inp); 1364 if (result) 1365 IPSEC6STAT_INC(ips_in_polvio); 1366 1367 return (result); 1368 } 1369 #endif 1370 1371 /* 1372 * Compute the byte size to be occupied by IPsec header. 1373 * In case it is tunnelled, it includes the size of outer IP header. 1374 * NOTE: SP passed is freed in this function. 1375 */ 1376 static size_t 1377 ipsec_hdrsiz_internal(struct secpolicy *sp) 1378 { 1379 struct ipsecrequest *isr; 1380 size_t size; 1381 1382 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1383 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1384 1385 switch (sp->policy) { 1386 case IPSEC_POLICY_DISCARD: 1387 case IPSEC_POLICY_BYPASS: 1388 case IPSEC_POLICY_NONE: 1389 return (0); 1390 } 1391 1392 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1393 ("invalid policy %u", sp->policy)); 1394 1395 size = 0; 1396 for (isr = sp->req; isr != NULL; isr = isr->next) { 1397 size_t clen = 0; 1398 1399 switch (isr->saidx.proto) { 1400 case IPPROTO_ESP: 1401 clen = esp_hdrsiz(isr->sav); 1402 break; 1403 case IPPROTO_AH: 1404 clen = ah_hdrsiz(isr->sav); 1405 break; 1406 case IPPROTO_IPCOMP: 1407 clen = sizeof(struct ipcomp); 1408 break; 1409 } 1410 1411 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1412 switch (isr->saidx.dst.sa.sa_family) { 1413 case AF_INET: 1414 clen += sizeof(struct ip); 1415 break; 1416 #ifdef INET6 1417 case AF_INET6: 1418 clen += sizeof(struct ip6_hdr); 1419 break; 1420 #endif 1421 default: 1422 ipseclog((LOG_ERR, "%s: unknown AF %d in " 1423 "IPsec tunnel SA\n", __func__, 1424 ((struct sockaddr *)&isr->saidx.dst)->sa_family)); 1425 break; 1426 } 1427 } 1428 size += clen; 1429 } 1430 1431 return (size); 1432 } 1433 1434 /* 1435 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(), 1436 * disabled ip6_ipsec_mtu() and ip6_forward(). 1437 */ 1438 size_t 1439 ipsec_hdrsiz(const struct mbuf *m, u_int dir, struct inpcb *inp) 1440 { 1441 struct secpolicy *sp; 1442 int error; 1443 size_t size; 1444 1445 if (!key_havesp(dir)) 1446 return 0; 1447 1448 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1449 1450 /* Get SP for this packet. */ 1451 if (inp == NULL) 1452 sp = ipsec_getpolicybyaddr(m, dir, &error); 1453 else 1454 sp = ipsec_getpolicybysock(m, dir, inp, &error); 1455 1456 if (sp != NULL) { 1457 size = ipsec_hdrsiz_internal(sp); 1458 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1459 printf("%s: size:%lu.\n", __func__, 1460 (unsigned long)size)); 1461 1462 KEY_FREESP(&sp); 1463 } else { 1464 size = 0; /* XXX Should be panic? 1465 * -> No, we are called w/o knowing if 1466 * IPsec processing is needed. */ 1467 } 1468 return (size); 1469 } 1470 1471 /* 1472 * Check the variable replay window. 1473 * ipsec_chkreplay() performs replay check before ICV verification. 1474 * ipsec_updatereplay() updates replay bitmap. This must be called after 1475 * ICV verification (it also performs replay check, which is usually done 1476 * beforehand). 1477 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1478 * 1479 * Based on RFC 2401. 1480 */ 1481 int 1482 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav) 1483 { 1484 const struct secreplay *replay; 1485 u_int32_t diff; 1486 int fr; 1487 u_int32_t wsizeb; /* Constant: bits of window size. */ 1488 int frlast; /* Constant: last frame. */ 1489 1490 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1491 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1492 1493 replay = sav->replay; 1494 1495 if (replay->wsize == 0) 1496 return (1); /* No need to check replay. */ 1497 1498 /* Constant. */ 1499 frlast = replay->wsize - 1; 1500 wsizeb = replay->wsize << 3; 1501 1502 /* Sequence number of 0 is invalid. */ 1503 if (seq == 0) 1504 return (0); 1505 1506 /* First time is always okay. */ 1507 if (replay->count == 0) 1508 return (1); 1509 1510 if (seq > replay->lastseq) { 1511 /* Larger sequences are okay. */ 1512 return (1); 1513 } else { 1514 /* seq is equal or less than lastseq. */ 1515 diff = replay->lastseq - seq; 1516 1517 /* Over range to check, i.e. too old or wrapped. */ 1518 if (diff >= wsizeb) 1519 return (0); 1520 1521 fr = frlast - diff / 8; 1522 1523 /* This packet already seen? */ 1524 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1525 return (0); 1526 1527 /* Out of order but good. */ 1528 return (1); 1529 } 1530 } 1531 1532 /* 1533 * Check replay counter whether to update or not. 1534 * OUT: 0: OK 1535 * 1: NG 1536 */ 1537 int 1538 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav) 1539 { 1540 char buf[128]; 1541 struct secreplay *replay; 1542 u_int32_t diff; 1543 int fr; 1544 u_int32_t wsizeb; /* Constant: bits of window size. */ 1545 int frlast; /* Constant: last frame. */ 1546 1547 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1548 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1549 1550 replay = sav->replay; 1551 1552 if (replay->wsize == 0) 1553 goto ok; /* No need to check replay. */ 1554 1555 /* Constant. */ 1556 frlast = replay->wsize - 1; 1557 wsizeb = replay->wsize << 3; 1558 1559 /* Sequence number of 0 is invalid. */ 1560 if (seq == 0) 1561 return (1); 1562 1563 /* First time. */ 1564 if (replay->count == 0) { 1565 replay->lastseq = seq; 1566 bzero(replay->bitmap, replay->wsize); 1567 (replay->bitmap)[frlast] = 1; 1568 goto ok; 1569 } 1570 1571 if (seq > replay->lastseq) { 1572 /* seq is larger than lastseq. */ 1573 diff = seq - replay->lastseq; 1574 1575 /* New larger sequence number. */ 1576 if (diff < wsizeb) { 1577 /* In window. */ 1578 /* Set bit for this packet. */ 1579 vshiftl(replay->bitmap, diff, replay->wsize); 1580 (replay->bitmap)[frlast] |= 1; 1581 } else { 1582 /* This packet has a "way larger". */ 1583 bzero(replay->bitmap, replay->wsize); 1584 (replay->bitmap)[frlast] = 1; 1585 } 1586 replay->lastseq = seq; 1587 1588 /* Larger is good. */ 1589 } else { 1590 /* seq is equal or less than lastseq. */ 1591 diff = replay->lastseq - seq; 1592 1593 /* Over range to check, i.e. too old or wrapped. */ 1594 if (diff >= wsizeb) 1595 return (1); 1596 1597 fr = frlast - diff / 8; 1598 1599 /* This packet already seen? */ 1600 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1601 return (1); 1602 1603 /* Mark as seen. */ 1604 (replay->bitmap)[fr] |= (1 << (diff % 8)); 1605 1606 /* Out of order but good. */ 1607 } 1608 1609 ok: 1610 if (replay->count == ~0) { 1611 1612 /* Set overflow flag. */ 1613 replay->overflow++; 1614 1615 /* Don't increment, no more packets accepted. */ 1616 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 1617 return (1); 1618 1619 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1620 __func__, replay->overflow, 1621 ipsec_logsastr(sav, buf, sizeof(buf)))); 1622 } 1623 1624 replay->count++; 1625 1626 return (0); 1627 } 1628 1629 /* 1630 * Shift variable length buffer to left. 1631 * IN: bitmap: pointer to the buffer 1632 * nbit: the number of to shift. 1633 * wsize: buffer size (bytes). 1634 */ 1635 static void 1636 vshiftl(unsigned char *bitmap, int nbit, int wsize) 1637 { 1638 int s, j, i; 1639 unsigned char over; 1640 1641 for (j = 0; j < nbit; j += 8) { 1642 s = (nbit - j < 8) ? (nbit - j): 8; 1643 bitmap[0] <<= s; 1644 for (i = 1; i < wsize; i++) { 1645 over = (bitmap[i] >> (8 - s)); 1646 bitmap[i] <<= s; 1647 bitmap[i-1] |= over; 1648 } 1649 } 1650 } 1651 1652 /* Return a printable string for the address. */ 1653 char* 1654 ipsec_address(union sockaddr_union* sa, char *buf, socklen_t size) 1655 { 1656 1657 switch (sa->sa.sa_family) { 1658 #ifdef INET 1659 case AF_INET: 1660 return (inet_ntop(AF_INET, &sa->sin.sin_addr, buf, size)); 1661 #endif /* INET */ 1662 #ifdef INET6 1663 case AF_INET6: 1664 return (inet_ntop(AF_INET6, &sa->sin6.sin6_addr, buf, size)); 1665 #endif /* INET6 */ 1666 default: 1667 return ("(unknown address family)"); 1668 } 1669 } 1670 1671 char * 1672 ipsec_logsastr(struct secasvar *sav, char *buf, size_t size) 1673 { 1674 char sbuf[INET6_ADDRSTRLEN], dbuf[INET6_ADDRSTRLEN]; 1675 1676 IPSEC_ASSERT(sav->sah->saidx.src.sa.sa_family == 1677 sav->sah->saidx.dst.sa.sa_family, ("address family mismatch")); 1678 1679 snprintf(buf, size, "SA(SPI=%08lx src=%s dst=%s)", 1680 (u_long)ntohl(sav->spi), 1681 ipsec_address(&sav->sah->saidx.src, sbuf, sizeof(sbuf)), 1682 ipsec_address(&sav->sah->saidx.dst, dbuf, sizeof(dbuf))); 1683 return (buf); 1684 } 1685 1686 void 1687 ipsec_dumpmbuf(const struct mbuf *m) 1688 { 1689 const u_char *p; 1690 int totlen; 1691 int i; 1692 1693 totlen = 0; 1694 printf("---\n"); 1695 while (m) { 1696 p = mtod(m, const u_char *); 1697 for (i = 0; i < m->m_len; i++) { 1698 printf("%02x ", p[i]); 1699 totlen++; 1700 if (totlen % 16 == 0) 1701 printf("\n"); 1702 } 1703 m = m->m_next; 1704 } 1705 if (totlen % 16 != 0) 1706 printf("\n"); 1707 printf("---\n"); 1708 } 1709 1710 static void 1711 def_policy_init(const void *unused __unused) 1712 { 1713 1714 bzero(&V_def_policy, sizeof(struct secpolicy)); 1715 V_def_policy.policy = IPSEC_POLICY_NONE; 1716 V_def_policy.refcnt = 1; 1717 } 1718 VNET_SYSINIT(def_policy_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST, 1719 def_policy_init, NULL); 1720 1721 1722 /* XXX This stuff doesn't belong here... */ 1723 1724 static struct xformsw* xforms = NULL; 1725 1726 /* 1727 * Register a transform; typically at system startup. 1728 */ 1729 void 1730 xform_register(struct xformsw* xsp) 1731 { 1732 1733 xsp->xf_next = xforms; 1734 xforms = xsp; 1735 } 1736 1737 /* 1738 * Initialize transform support in an sav. 1739 */ 1740 int 1741 xform_init(struct secasvar *sav, int xftype) 1742 { 1743 struct xformsw *xsp; 1744 1745 if (sav->tdb_xform != NULL) /* Previously initialized. */ 1746 return (0); 1747 for (xsp = xforms; xsp; xsp = xsp->xf_next) 1748 if (xsp->xf_type == xftype) 1749 return ((*xsp->xf_init)(sav, xsp)); 1750 return (EINVAL); 1751 } 1752