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 occured. 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 occured. 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 occured. 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 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 2401. 1479 */ 1480 int 1481 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav) 1482 { 1483 const struct secreplay *replay; 1484 u_int32_t diff; 1485 int fr; 1486 u_int32_t wsizeb; /* Constant: bits of window size. */ 1487 int frlast; /* Constant: last frame. */ 1488 1489 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1490 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1491 1492 replay = sav->replay; 1493 1494 if (replay->wsize == 0) 1495 return (1); /* No need to check replay. */ 1496 1497 /* Constant. */ 1498 frlast = replay->wsize - 1; 1499 wsizeb = replay->wsize << 3; 1500 1501 /* Sequence number of 0 is invalid. */ 1502 if (seq == 0) 1503 return (0); 1504 1505 /* First time is always okay. */ 1506 if (replay->count == 0) 1507 return (1); 1508 1509 if (seq > replay->lastseq) { 1510 /* Larger sequences are okay. */ 1511 return (1); 1512 } else { 1513 /* seq is equal or less than lastseq. */ 1514 diff = replay->lastseq - seq; 1515 1516 /* Over range to check, i.e. too old or wrapped. */ 1517 if (diff >= wsizeb) 1518 return (0); 1519 1520 fr = frlast - diff / 8; 1521 1522 /* This packet already seen? */ 1523 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1524 return (0); 1525 1526 /* Out of order but good. */ 1527 return (1); 1528 } 1529 } 1530 1531 /* 1532 * Check replay counter whether to update or not. 1533 * OUT: 0: OK 1534 * 1: NG 1535 */ 1536 int 1537 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav) 1538 { 1539 char buf[128]; 1540 struct secreplay *replay; 1541 u_int32_t diff; 1542 int fr; 1543 u_int32_t wsizeb; /* Constant: bits of window size. */ 1544 int frlast; /* Constant: last frame. */ 1545 1546 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1547 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1548 1549 replay = sav->replay; 1550 1551 if (replay->wsize == 0) 1552 goto ok; /* No need to check replay. */ 1553 1554 /* Constant. */ 1555 frlast = replay->wsize - 1; 1556 wsizeb = replay->wsize << 3; 1557 1558 /* Sequence number of 0 is invalid. */ 1559 if (seq == 0) 1560 return (1); 1561 1562 /* First time. */ 1563 if (replay->count == 0) { 1564 replay->lastseq = seq; 1565 bzero(replay->bitmap, replay->wsize); 1566 (replay->bitmap)[frlast] = 1; 1567 goto ok; 1568 } 1569 1570 if (seq > replay->lastseq) { 1571 /* seq is larger than lastseq. */ 1572 diff = seq - replay->lastseq; 1573 1574 /* New larger sequence number. */ 1575 if (diff < wsizeb) { 1576 /* In window. */ 1577 /* Set bit for this packet. */ 1578 vshiftl(replay->bitmap, diff, replay->wsize); 1579 (replay->bitmap)[frlast] |= 1; 1580 } else { 1581 /* This packet has a "way larger". */ 1582 bzero(replay->bitmap, replay->wsize); 1583 (replay->bitmap)[frlast] = 1; 1584 } 1585 replay->lastseq = seq; 1586 1587 /* Larger is good. */ 1588 } else { 1589 /* seq is equal or less than lastseq. */ 1590 diff = replay->lastseq - seq; 1591 1592 /* Over range to check, i.e. too old or wrapped. */ 1593 if (diff >= wsizeb) 1594 return (1); 1595 1596 fr = frlast - diff / 8; 1597 1598 /* This packet already seen? */ 1599 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1600 return (1); 1601 1602 /* Mark as seen. */ 1603 (replay->bitmap)[fr] |= (1 << (diff % 8)); 1604 1605 /* Out of order but good. */ 1606 } 1607 1608 ok: 1609 if (replay->count == ~0) { 1610 1611 /* Set overflow flag. */ 1612 replay->overflow++; 1613 1614 /* Don't increment, no more packets accepted. */ 1615 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 1616 return (1); 1617 1618 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1619 __func__, replay->overflow, 1620 ipsec_logsastr(sav, buf, sizeof(buf)))); 1621 } 1622 1623 replay->count++; 1624 1625 return (0); 1626 } 1627 1628 /* 1629 * Shift variable length buffer to left. 1630 * IN: bitmap: pointer to the buffer 1631 * nbit: the number of to shift. 1632 * wsize: buffer size (bytes). 1633 */ 1634 static void 1635 vshiftl(unsigned char *bitmap, int nbit, int wsize) 1636 { 1637 int s, j, i; 1638 unsigned char over; 1639 1640 for (j = 0; j < nbit; j += 8) { 1641 s = (nbit - j < 8) ? (nbit - j): 8; 1642 bitmap[0] <<= s; 1643 for (i = 1; i < wsize; i++) { 1644 over = (bitmap[i] >> (8 - s)); 1645 bitmap[i] <<= s; 1646 bitmap[i-1] |= over; 1647 } 1648 } 1649 } 1650 1651 /* Return a printable string for the address. */ 1652 char* 1653 ipsec_address(union sockaddr_union* sa, char *buf, socklen_t size) 1654 { 1655 1656 switch (sa->sa.sa_family) { 1657 #ifdef INET 1658 case AF_INET: 1659 return (inet_ntop(AF_INET, &sa->sin.sin_addr, buf, size)); 1660 #endif /* INET */ 1661 #ifdef INET6 1662 case AF_INET6: 1663 return (inet_ntop(AF_INET6, &sa->sin6.sin6_addr, buf, size)); 1664 #endif /* INET6 */ 1665 default: 1666 return ("(unknown address family)"); 1667 } 1668 } 1669 1670 char * 1671 ipsec_logsastr(struct secasvar *sav, char *buf, size_t size) 1672 { 1673 char sbuf[INET6_ADDRSTRLEN], dbuf[INET6_ADDRSTRLEN]; 1674 1675 IPSEC_ASSERT(sav->sah->saidx.src.sa.sa_family == 1676 sav->sah->saidx.dst.sa.sa_family, ("address family mismatch")); 1677 1678 snprintf(buf, size, "SA(SPI=%08lx src=%s dst=%s)", 1679 (u_long)ntohl(sav->spi), 1680 ipsec_address(&sav->sah->saidx.src, sbuf, sizeof(sbuf)), 1681 ipsec_address(&sav->sah->saidx.dst, dbuf, sizeof(dbuf))); 1682 return (buf); 1683 } 1684 1685 void 1686 ipsec_dumpmbuf(const struct mbuf *m) 1687 { 1688 const u_char *p; 1689 int totlen; 1690 int i; 1691 1692 totlen = 0; 1693 printf("---\n"); 1694 while (m) { 1695 p = mtod(m, const u_char *); 1696 for (i = 0; i < m->m_len; i++) { 1697 printf("%02x ", p[i]); 1698 totlen++; 1699 if (totlen % 16 == 0) 1700 printf("\n"); 1701 } 1702 m = m->m_next; 1703 } 1704 if (totlen % 16 != 0) 1705 printf("\n"); 1706 printf("---\n"); 1707 } 1708 1709 static void 1710 def_policy_init(const void *unused __unused) 1711 { 1712 1713 bzero(&V_def_policy, sizeof(struct secpolicy)); 1714 V_def_policy.policy = IPSEC_POLICY_NONE; 1715 V_def_policy.refcnt = 1; 1716 } 1717 VNET_SYSINIT(def_policy_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, 1718 def_policy_init, NULL); 1719 1720 1721 /* XXX This stuff doesn't belong here... */ 1722 1723 static struct xformsw* xforms = NULL; 1724 1725 /* 1726 * Register a transform; typically at system startup. 1727 */ 1728 void 1729 xform_register(struct xformsw* xsp) 1730 { 1731 1732 xsp->xf_next = xforms; 1733 xforms = xsp; 1734 } 1735 1736 /* 1737 * Initialize transform support in an sav. 1738 */ 1739 int 1740 xform_init(struct secasvar *sav, int xftype) 1741 { 1742 struct xformsw *xsp; 1743 1744 if (sav->tdb_xform != NULL) /* Previously initialized. */ 1745 return (0); 1746 for (xsp = xforms; xsp; xsp = xsp->xf_next) 1747 if (xsp->xf_type == xftype) 1748 return ((*xsp->xf_init)(sav, xsp)); 1749 return (EINVAL); 1750 } 1751