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 *, struct mbuf *); 244 static int ipsec_setspidx_inpcb(struct mbuf *, struct inpcb *); 245 static int ipsec_setspidx(struct mbuf *, struct secpolicyindex *, int); 246 static void ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *, int); 247 static int ipsec4_setspidx_ipaddr(struct mbuf *, struct secpolicyindex *); 248 #ifdef INET6 249 static void ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *, int); 250 static int ipsec6_setspidx_ipaddr(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(struct mbuf *m, u_int dir, struct inpcb *inp, int *error) 328 { 329 struct inpcbpolicy *pcbsp; 330 struct secpolicy *currsp = NULL; /* Policy on socket. */ 331 struct secpolicy *sp; 332 333 IPSEC_ASSERT(m != NULL, ("null mbuf")); 334 IPSEC_ASSERT(inp != NULL, ("null inpcb")); 335 IPSEC_ASSERT(error != NULL, ("null error")); 336 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 337 ("invalid direction %u", dir)); 338 339 if (!key_havesp(dir)) { 340 /* No SP found, use system default. */ 341 sp = KEY_ALLOCSP_DEFAULT(); 342 return (sp); 343 } 344 345 /* Set spidx in pcb. */ 346 *error = ipsec_setspidx_inpcb(m, inp); 347 if (*error) 348 return (NULL); 349 350 pcbsp = inp->inp_sp; 351 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp")); 352 switch (dir) { 353 case IPSEC_DIR_INBOUND: 354 currsp = pcbsp->sp_in; 355 break; 356 case IPSEC_DIR_OUTBOUND: 357 currsp = pcbsp->sp_out; 358 break; 359 } 360 IPSEC_ASSERT(currsp != NULL, ("null currsp")); 361 362 if (pcbsp->priv) { /* When privilieged socket. */ 363 switch (currsp->policy) { 364 case IPSEC_POLICY_BYPASS: 365 case IPSEC_POLICY_IPSEC: 366 key_addref(currsp); 367 sp = currsp; 368 break; 369 370 case IPSEC_POLICY_ENTRUST: 371 /* Look for a policy in SPD. */ 372 sp = KEY_ALLOCSP(&currsp->spidx, dir); 373 if (sp == NULL) /* No SP found. */ 374 sp = KEY_ALLOCSP_DEFAULT(); 375 break; 376 377 default: 378 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n", 379 __func__, currsp->policy)); 380 *error = EINVAL; 381 return (NULL); 382 } 383 } else { /* Unpriv, SPD has policy. */ 384 sp = KEY_ALLOCSP(&currsp->spidx, dir); 385 if (sp == NULL) { /* No SP found. */ 386 switch (currsp->policy) { 387 case IPSEC_POLICY_BYPASS: 388 ipseclog((LOG_ERR, "%s: Illegal policy for " 389 "non-priviliged defined %d\n", 390 __func__, currsp->policy)); 391 *error = EINVAL; 392 return (NULL); 393 394 case IPSEC_POLICY_ENTRUST: 395 sp = KEY_ALLOCSP_DEFAULT(); 396 break; 397 398 case IPSEC_POLICY_IPSEC: 399 key_addref(currsp); 400 sp = currsp; 401 break; 402 403 default: 404 ipseclog((LOG_ERR, "%s: Invalid policy for " 405 "PCB %d\n", __func__, currsp->policy)); 406 *error = EINVAL; 407 return (NULL); 408 } 409 } 410 } 411 IPSEC_ASSERT(sp != NULL, 412 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy)); 413 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 414 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n", 415 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt)); 416 return (sp); 417 } 418 419 /* 420 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 421 * and return a pointer to SP. 422 * OUT: positive: a pointer to the entry for security policy leaf matched. 423 * NULL: no apropreate SP found, the following value is set to error. 424 * 0 : bypass 425 * EACCES : discard packet. 426 * ENOENT : ipsec_acquire() in progress, maybe. 427 * others : error occured. 428 */ 429 struct secpolicy * 430 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int *error) 431 { 432 struct secpolicyindex spidx; 433 struct secpolicy *sp; 434 435 IPSEC_ASSERT(m != NULL, ("null mbuf")); 436 IPSEC_ASSERT(error != NULL, ("null error")); 437 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 438 ("invalid direction %u", dir)); 439 440 sp = NULL; 441 *error = 0; 442 if (key_havesp(dir)) { 443 /* Make an index to look for a policy. */ 444 *error = ipsec_setspidx(m, &spidx, 0); 445 if (*error != 0) { 446 DPRINTF(("%s: setpidx failed, dir %u\n", 447 __func__, dir)); 448 return (NULL); 449 } 450 spidx.dir = dir; 451 sp = KEY_ALLOCSP(&spidx, dir); 452 } 453 if (sp == NULL) /* No SP found, use system default. */ 454 sp = KEY_ALLOCSP_DEFAULT(); 455 IPSEC_ASSERT(sp != NULL, ("null SP")); 456 return (sp); 457 } 458 459 struct secpolicy * 460 ipsec4_checkpolicy(struct mbuf *m, u_int dir, int *error, struct inpcb *inp) 461 { 462 struct secpolicy *sp; 463 464 *error = 0; 465 if (inp == NULL) 466 sp = ipsec_getpolicybyaddr(m, dir, error); 467 else 468 sp = ipsec_getpolicybysock(m, dir, inp, error); 469 if (sp == NULL) { 470 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error")); 471 IPSECSTAT_INC(ips_out_inval); 472 return (NULL); 473 } 474 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error)); 475 switch (sp->policy) { 476 case IPSEC_POLICY_ENTRUST: 477 default: 478 printf("%s: invalid policy %u\n", __func__, sp->policy); 479 /* FALLTHROUGH */ 480 case IPSEC_POLICY_DISCARD: 481 IPSECSTAT_INC(ips_out_polvio); 482 *error = -EINVAL; /* Packet is discarded by caller. */ 483 break; 484 case IPSEC_POLICY_BYPASS: 485 case IPSEC_POLICY_NONE: 486 KEY_FREESP(&sp); 487 sp = NULL; /* NB: force NULL result. */ 488 break; 489 case IPSEC_POLICY_IPSEC: 490 if (sp->req == NULL) /* Acquire a SA. */ 491 *error = key_spdacquire(sp); 492 break; 493 } 494 if (*error != 0) { 495 KEY_FREESP(&sp); 496 sp = NULL; 497 } 498 return (sp); 499 } 500 501 static int 502 ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp) 503 { 504 int error; 505 506 IPSEC_ASSERT(inp != NULL, ("null inp")); 507 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 508 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL, 509 ("null sp_in || sp_out")); 510 511 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1); 512 if (error == 0) { 513 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 514 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx; 515 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 516 } else { 517 bzero(&inp->inp_sp->sp_in->spidx, 518 sizeof (inp->inp_sp->sp_in->spidx)); 519 bzero(&inp->inp_sp->sp_out->spidx, 520 sizeof (inp->inp_sp->sp_in->spidx)); 521 } 522 return (error); 523 } 524 525 /* 526 * Configure security policy index (src/dst/proto/sport/dport) 527 * by looking at the content of mbuf. 528 * The caller is responsible for error recovery (like clearing up spidx). 529 */ 530 static int 531 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 532 { 533 struct ip *ip = NULL; 534 struct ip ipbuf; 535 u_int v; 536 struct mbuf *n; 537 int len; 538 int error; 539 540 IPSEC_ASSERT(m != NULL, ("null mbuf")); 541 542 /* 543 * Validate m->m_pkthdr.len. We see incorrect length if we 544 * mistakenly call this function with inconsistent mbuf chain 545 * (like 4.4BSD tcp/udp processing). XXX Should we panic here? 546 */ 547 len = 0; 548 for (n = m; n; n = n->m_next) 549 len += n->m_len; 550 if (m->m_pkthdr.len != len) { 551 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 552 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n", 553 __func__, len, m->m_pkthdr.len)); 554 return (EINVAL); 555 } 556 557 if (m->m_pkthdr.len < sizeof(struct ip)) { 558 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 559 printf("%s: pkthdr len(%d) too small (v4), ignored.\n", 560 __func__, m->m_pkthdr.len)); 561 return (EINVAL); 562 } 563 564 if (m->m_len >= sizeof(*ip)) 565 ip = mtod(m, struct ip *); 566 else { 567 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf); 568 ip = &ipbuf; 569 } 570 v = ip->ip_v; 571 switch (v) { 572 case 4: 573 error = ipsec4_setspidx_ipaddr(m, spidx); 574 if (error) 575 return (error); 576 ipsec4_get_ulp(m, spidx, needport); 577 return (0); 578 #ifdef INET6 579 case 6: 580 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 581 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 582 printf("%s: pkthdr len(%d) too small (v6), " 583 "ignored\n", __func__, m->m_pkthdr.len)); 584 return (EINVAL); 585 } 586 error = ipsec6_setspidx_ipaddr(m, spidx); 587 if (error) 588 return (error); 589 ipsec6_get_ulp(m, spidx, needport); 590 return (0); 591 #endif 592 default: 593 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 594 printf("%s: " "unknown IP version %u, ignored.\n", 595 __func__, v)); 596 return (EINVAL); 597 } 598 } 599 600 static void 601 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 602 { 603 u_int8_t nxt; 604 int off; 605 606 /* Sanity check. */ 607 IPSEC_ASSERT(m != NULL, ("null mbuf")); 608 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short")); 609 610 if (m->m_len >= sizeof (struct ip)) { 611 struct ip *ip = mtod(m, struct ip *); 612 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 613 goto done; 614 off = ip->ip_hl << 2; 615 nxt = ip->ip_p; 616 } else { 617 struct ip ih; 618 619 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih); 620 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 621 goto done; 622 off = ih.ip_hl << 2; 623 nxt = ih.ip_p; 624 } 625 626 while (off < m->m_pkthdr.len) { 627 struct ip6_ext ip6e; 628 struct tcphdr th; 629 struct udphdr uh; 630 631 switch (nxt) { 632 case IPPROTO_TCP: 633 spidx->ul_proto = nxt; 634 if (!needport) 635 goto done_proto; 636 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 637 goto done; 638 m_copydata(m, off, sizeof (th), (caddr_t) &th); 639 spidx->src.sin.sin_port = th.th_sport; 640 spidx->dst.sin.sin_port = th.th_dport; 641 return; 642 case IPPROTO_UDP: 643 spidx->ul_proto = nxt; 644 if (!needport) 645 goto done_proto; 646 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 647 goto done; 648 m_copydata(m, off, sizeof (uh), (caddr_t) &uh); 649 spidx->src.sin.sin_port = uh.uh_sport; 650 spidx->dst.sin.sin_port = uh.uh_dport; 651 return; 652 case IPPROTO_AH: 653 if (off + sizeof(ip6e) > m->m_pkthdr.len) 654 goto done; 655 /* XXX Sigh, this works but is totally bogus. */ 656 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e); 657 off += (ip6e.ip6e_len + 2) << 2; 658 nxt = ip6e.ip6e_nxt; 659 break; 660 case IPPROTO_ICMP: 661 default: 662 /* XXX Intermediate headers??? */ 663 spidx->ul_proto = nxt; 664 goto done_proto; 665 } 666 } 667 done: 668 spidx->ul_proto = IPSEC_ULPROTO_ANY; 669 done_proto: 670 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 671 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 672 } 673 674 /* Assumes that m is sane. */ 675 static int 676 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 677 { 678 static const struct sockaddr_in template = { 679 sizeof (struct sockaddr_in), 680 AF_INET, 681 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 682 }; 683 684 spidx->src.sin = template; 685 spidx->dst.sin = template; 686 687 if (m->m_len < sizeof (struct ip)) { 688 m_copydata(m, offsetof(struct ip, ip_src), 689 sizeof (struct in_addr), 690 (caddr_t) &spidx->src.sin.sin_addr); 691 m_copydata(m, offsetof(struct ip, ip_dst), 692 sizeof (struct in_addr), 693 (caddr_t) &spidx->dst.sin.sin_addr); 694 } else { 695 struct ip *ip = mtod(m, struct ip *); 696 spidx->src.sin.sin_addr = ip->ip_src; 697 spidx->dst.sin.sin_addr = ip->ip_dst; 698 } 699 700 spidx->prefs = sizeof(struct in_addr) << 3; 701 spidx->prefd = sizeof(struct in_addr) << 3; 702 703 return (0); 704 } 705 706 #ifdef INET6 707 static void 708 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 709 { 710 int off, nxt; 711 struct tcphdr th; 712 struct udphdr uh; 713 struct icmp6_hdr ih; 714 715 /* Sanity check. */ 716 if (m == NULL) 717 panic("%s: NULL pointer was passed.\n", __func__); 718 719 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 720 printf("%s:\n", __func__); kdebug_mbuf(m)); 721 722 /* Set default. */ 723 spidx->ul_proto = IPSEC_ULPROTO_ANY; 724 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 725 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 726 727 nxt = -1; 728 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 729 if (off < 0 || m->m_pkthdr.len < off) 730 return; 731 732 switch (nxt) { 733 case IPPROTO_TCP: 734 spidx->ul_proto = nxt; 735 if (!needport) 736 break; 737 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 738 break; 739 m_copydata(m, off, sizeof(th), (caddr_t)&th); 740 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 741 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 742 break; 743 case IPPROTO_UDP: 744 spidx->ul_proto = nxt; 745 if (!needport) 746 break; 747 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 748 break; 749 m_copydata(m, off, sizeof(uh), (caddr_t)&uh); 750 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 751 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 752 break; 753 case IPPROTO_ICMPV6: 754 spidx->ul_proto = nxt; 755 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 756 break; 757 m_copydata(m, off, sizeof(ih), (caddr_t)&ih); 758 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 759 htons((uint16_t)ih.icmp6_type); 760 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 761 htons((uint16_t)ih.icmp6_code); 762 break; 763 default: 764 /* XXX Intermediate headers??? */ 765 spidx->ul_proto = nxt; 766 break; 767 } 768 } 769 770 /* Assumes that m is sane. */ 771 static int 772 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 773 { 774 struct ip6_hdr *ip6 = NULL; 775 struct ip6_hdr ip6buf; 776 struct sockaddr_in6 *sin6; 777 778 if (m->m_len >= sizeof(*ip6)) 779 ip6 = mtod(m, struct ip6_hdr *); 780 else { 781 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf); 782 ip6 = &ip6buf; 783 } 784 785 sin6 = (struct sockaddr_in6 *)&spidx->src; 786 bzero(sin6, sizeof(*sin6)); 787 sin6->sin6_family = AF_INET6; 788 sin6->sin6_len = sizeof(struct sockaddr_in6); 789 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src)); 790 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 791 sin6->sin6_addr.s6_addr16[1] = 0; 792 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 793 } 794 spidx->prefs = sizeof(struct in6_addr) << 3; 795 796 sin6 = (struct sockaddr_in6 *)&spidx->dst; 797 bzero(sin6, sizeof(*sin6)); 798 sin6->sin6_family = AF_INET6; 799 sin6->sin6_len = sizeof(struct sockaddr_in6); 800 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst)); 801 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 802 sin6->sin6_addr.s6_addr16[1] = 0; 803 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 804 } 805 spidx->prefd = sizeof(struct in6_addr) << 3; 806 807 return (0); 808 } 809 #endif 810 811 int 812 ipsec_run_hhooks(struct ipsec_ctx_data *ctx, int type) 813 { 814 int idx; 815 816 switch (ctx->af) { 817 #ifdef INET 818 case AF_INET: 819 idx = HHOOK_IPSEC_INET; 820 break; 821 #endif 822 #ifdef INET6 823 case AF_INET6: 824 idx = HHOOK_IPSEC_INET6; 825 break; 826 #endif 827 default: 828 return (EPFNOSUPPORT); 829 } 830 if (type == HHOOK_TYPE_IPSEC_IN) 831 HHOOKS_RUN_IF(V_ipsec_hhh_in[idx], ctx, NULL); 832 else 833 HHOOKS_RUN_IF(V_ipsec_hhh_out[idx], ctx, NULL); 834 if (*ctx->mp == NULL) 835 return (EACCES); 836 return (0); 837 } 838 839 static void 840 ipsec_delpcbpolicy(struct inpcbpolicy *p) 841 { 842 843 free(p, M_IPSEC_INPCB); 844 } 845 846 /* Initialize policy in PCB. */ 847 int 848 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp) 849 { 850 struct inpcbpolicy *new; 851 852 /* Sanity check. */ 853 if (so == NULL || pcb_sp == NULL) 854 panic("%s: NULL pointer was passed.\n", __func__); 855 856 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy), 857 M_IPSEC_INPCB, M_NOWAIT|M_ZERO); 858 if (new == NULL) { 859 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 860 return (ENOBUFS); 861 } 862 863 new->priv = IPSEC_IS_PRIVILEGED_SO(so); 864 865 if ((new->sp_in = KEY_NEWSP()) == NULL) { 866 ipsec_delpcbpolicy(new); 867 return (ENOBUFS); 868 } 869 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 870 if ((new->sp_out = KEY_NEWSP()) == NULL) { 871 KEY_FREESP(&new->sp_in); 872 ipsec_delpcbpolicy(new); 873 return (ENOBUFS); 874 } 875 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 876 *pcb_sp = new; 877 878 return (0); 879 } 880 881 /* Copy old IPsec policy into new. */ 882 int 883 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new) 884 { 885 struct secpolicy *sp; 886 887 sp = ipsec_deepcopy_policy(old->sp_in); 888 if (sp) { 889 KEY_FREESP(&new->sp_in); 890 new->sp_in = sp; 891 } else 892 return (ENOBUFS); 893 894 sp = ipsec_deepcopy_policy(old->sp_out); 895 if (sp) { 896 KEY_FREESP(&new->sp_out); 897 new->sp_out = sp; 898 } else 899 return (ENOBUFS); 900 901 new->priv = old->priv; 902 903 return (0); 904 } 905 906 struct ipsecrequest * 907 ipsec_newisr(void) 908 { 909 struct ipsecrequest *p; 910 911 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO); 912 if (p != NULL) 913 IPSECREQUEST_LOCK_INIT(p); 914 return (p); 915 } 916 917 void 918 ipsec_delisr(struct ipsecrequest *p) 919 { 920 921 IPSECREQUEST_LOCK_DESTROY(p); 922 free(p, M_IPSEC_SR); 923 } 924 925 /* Deep-copy a policy in PCB. */ 926 static struct secpolicy * 927 ipsec_deepcopy_policy(struct secpolicy *src) 928 { 929 struct ipsecrequest *newchain = NULL; 930 struct ipsecrequest *p; 931 struct ipsecrequest **q; 932 struct ipsecrequest *r; 933 struct secpolicy *dst; 934 935 if (src == NULL) 936 return (NULL); 937 dst = KEY_NEWSP(); 938 if (dst == NULL) 939 return (NULL); 940 941 /* 942 * Deep-copy IPsec request chain. This is required since struct 943 * ipsecrequest is not reference counted. 944 */ 945 q = &newchain; 946 for (p = src->req; p; p = p->next) { 947 *q = ipsec_newisr(); 948 if (*q == NULL) 949 goto fail; 950 (*q)->saidx.proto = p->saidx.proto; 951 (*q)->saidx.mode = p->saidx.mode; 952 (*q)->level = p->level; 953 (*q)->saidx.reqid = p->saidx.reqid; 954 955 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src)); 956 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst)); 957 958 (*q)->sp = dst; 959 960 q = &((*q)->next); 961 } 962 963 dst->req = newchain; 964 dst->policy = src->policy; 965 /* Do not touch the refcnt fields. */ 966 967 return (dst); 968 969 fail: 970 for (p = newchain; p; p = r) { 971 r = p->next; 972 ipsec_delisr(p); 973 p = NULL; 974 } 975 return (NULL); 976 } 977 978 /* Set policy and IPsec request if present. */ 979 static int 980 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname, 981 caddr_t request, size_t len, struct ucred *cred) 982 { 983 struct sadb_x_policy *xpl; 984 struct secpolicy *newsp = NULL; 985 int error; 986 987 /* Sanity check. */ 988 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL) 989 return (EINVAL); 990 if (len < sizeof(*xpl)) 991 return (EINVAL); 992 xpl = (struct sadb_x_policy *)request; 993 994 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 995 printf("%s: passed policy\n", __func__); 996 kdebug_sadb_x_policy((struct sadb_ext *)xpl)); 997 998 /* Check policy type. */ 999 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */ 1000 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 1001 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1002 return (EINVAL); 1003 1004 /* Check privileged socket. */ 1005 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1006 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0); 1007 if (error) 1008 return (EACCES); 1009 } 1010 1011 /* Allocating new SP entry. */ 1012 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1013 return (error); 1014 1015 /* Clear old SP and set new SP. */ 1016 KEY_FREESP(pcb_sp); 1017 *pcb_sp = newsp; 1018 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1019 printf("%s: new policy\n", __func__); 1020 kdebug_secpolicy(newsp)); 1021 1022 return (0); 1023 } 1024 1025 int 1026 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request, 1027 size_t len, struct ucred *cred) 1028 { 1029 struct sadb_x_policy *xpl; 1030 struct secpolicy **pcb_sp; 1031 1032 /* Sanity check. */ 1033 if (inp == NULL || request == NULL) 1034 return (EINVAL); 1035 if (len < sizeof(*xpl)) 1036 return (EINVAL); 1037 xpl = (struct sadb_x_policy *)request; 1038 1039 /* Select direction. */ 1040 switch (xpl->sadb_x_policy_dir) { 1041 case IPSEC_DIR_INBOUND: 1042 pcb_sp = &inp->inp_sp->sp_in; 1043 break; 1044 case IPSEC_DIR_OUTBOUND: 1045 pcb_sp = &inp->inp_sp->sp_out; 1046 break; 1047 default: 1048 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1049 xpl->sadb_x_policy_dir)); 1050 return (EINVAL); 1051 } 1052 1053 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred)); 1054 } 1055 1056 int 1057 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len, 1058 struct mbuf **mp) 1059 { 1060 struct sadb_x_policy *xpl; 1061 struct secpolicy *pcb_sp; 1062 1063 /* Sanity check. */ 1064 if (inp == NULL || request == NULL || mp == NULL) 1065 return (EINVAL); 1066 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 1067 if (len < sizeof(*xpl)) 1068 return (EINVAL); 1069 xpl = (struct sadb_x_policy *)request; 1070 1071 /* Select direction. */ 1072 switch (xpl->sadb_x_policy_dir) { 1073 case IPSEC_DIR_INBOUND: 1074 pcb_sp = inp->inp_sp->sp_in; 1075 break; 1076 case IPSEC_DIR_OUTBOUND: 1077 pcb_sp = inp->inp_sp->sp_out; 1078 break; 1079 default: 1080 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1081 xpl->sadb_x_policy_dir)); 1082 return (EINVAL); 1083 } 1084 1085 /* Sanity check. Should be an IPSEC_ASSERT. */ 1086 if (pcb_sp == NULL) 1087 return (EINVAL); 1088 1089 *mp = key_sp2msg(pcb_sp); 1090 if (!*mp) { 1091 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 1092 return (ENOBUFS); 1093 } 1094 1095 (*mp)->m_type = MT_DATA; 1096 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1097 printf("%s:\n", __func__); kdebug_mbuf(*mp)); 1098 1099 return (0); 1100 } 1101 1102 /* Delete policy in PCB. */ 1103 int 1104 ipsec_delete_pcbpolicy(struct inpcb *inp) 1105 { 1106 IPSEC_ASSERT(inp != NULL, ("null inp")); 1107 1108 if (inp->inp_sp == NULL) 1109 return (0); 1110 1111 if (inp->inp_sp->sp_in != NULL) 1112 KEY_FREESP(&inp->inp_sp->sp_in); 1113 1114 if (inp->inp_sp->sp_out != NULL) 1115 KEY_FREESP(&inp->inp_sp->sp_out); 1116 1117 ipsec_delpcbpolicy(inp->inp_sp); 1118 inp->inp_sp = NULL; 1119 1120 return (0); 1121 } 1122 1123 /* 1124 * Return current level. 1125 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1126 */ 1127 u_int 1128 ipsec_get_reqlevel(struct ipsecrequest *isr) 1129 { 1130 u_int level = 0; 1131 u_int esp_trans_deflev, esp_net_deflev; 1132 u_int ah_trans_deflev, ah_net_deflev; 1133 1134 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument")); 1135 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1136 ("af family mismatch, src %u, dst %u", 1137 isr->sp->spidx.src.sa.sa_family, 1138 isr->sp->spidx.dst.sa.sa_family)); 1139 1140 /* XXX Note that we have ipseclog() expanded here - code sync issue. */ 1141 #define IPSEC_CHECK_DEFAULT(lev) \ 1142 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1143 && (lev) != IPSEC_LEVEL_UNIQUE) \ 1144 ? (V_ipsec_debug \ 1145 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\ 1146 (lev), IPSEC_LEVEL_REQUIRE) \ 1147 : 0), \ 1148 (lev) = IPSEC_LEVEL_REQUIRE, \ 1149 (lev) \ 1150 : (lev)) 1151 1152 /* Set default level. */ 1153 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1154 #ifdef INET 1155 case AF_INET: 1156 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev); 1157 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev); 1158 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev); 1159 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev); 1160 break; 1161 #endif 1162 #ifdef INET6 1163 case AF_INET6: 1164 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev); 1165 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev); 1166 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev); 1167 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev); 1168 break; 1169 #endif /* INET6 */ 1170 default: 1171 panic("%s: unknown af %u", 1172 __func__, isr->sp->spidx.src.sa.sa_family); 1173 } 1174 1175 #undef IPSEC_CHECK_DEFAULT 1176 1177 /* Set level. */ 1178 switch (isr->level) { 1179 case IPSEC_LEVEL_DEFAULT: 1180 switch (isr->saidx.proto) { 1181 case IPPROTO_ESP: 1182 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1183 level = esp_net_deflev; 1184 else 1185 level = esp_trans_deflev; 1186 break; 1187 case IPPROTO_AH: 1188 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1189 level = ah_net_deflev; 1190 else 1191 level = ah_trans_deflev; 1192 break; 1193 case IPPROTO_IPCOMP: 1194 /* 1195 * We don't really care, as IPcomp document says that 1196 * we shouldn't compress small packets. 1197 */ 1198 level = IPSEC_LEVEL_USE; 1199 break; 1200 default: 1201 panic("%s: Illegal protocol defined %u\n", __func__, 1202 isr->saidx.proto); 1203 } 1204 break; 1205 1206 case IPSEC_LEVEL_USE: 1207 case IPSEC_LEVEL_REQUIRE: 1208 level = isr->level; 1209 break; 1210 case IPSEC_LEVEL_UNIQUE: 1211 level = IPSEC_LEVEL_REQUIRE; 1212 break; 1213 1214 default: 1215 panic("%s: Illegal IPsec level %u\n", __func__, isr->level); 1216 } 1217 1218 return (level); 1219 } 1220 1221 /* 1222 * Check security policy requirements against the actual 1223 * packet contents. Return one if the packet should be 1224 * reject as "invalid"; otherwiser return zero to have the 1225 * packet treated as "valid". 1226 * 1227 * OUT: 1228 * 0: valid 1229 * 1: invalid 1230 */ 1231 static int 1232 ipsec_in_reject(struct secpolicy *sp, struct mbuf *m) 1233 { 1234 struct ipsecrequest *isr; 1235 int need_auth; 1236 1237 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1238 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1239 1240 /* Check policy. */ 1241 switch (sp->policy) { 1242 case IPSEC_POLICY_DISCARD: 1243 return (1); 1244 case IPSEC_POLICY_BYPASS: 1245 case IPSEC_POLICY_NONE: 1246 return (0); 1247 } 1248 1249 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1250 ("invalid policy %u", sp->policy)); 1251 1252 /* XXX Should compare policy against IPsec header history. */ 1253 1254 need_auth = 0; 1255 for (isr = sp->req; isr != NULL; isr = isr->next) { 1256 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1257 continue; 1258 switch (isr->saidx.proto) { 1259 case IPPROTO_ESP: 1260 if ((m->m_flags & M_DECRYPTED) == 0) { 1261 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1262 printf("%s: ESP m_flags:%x\n", __func__, 1263 m->m_flags)); 1264 return (1); 1265 } 1266 1267 if (!need_auth && 1268 isr->sav != NULL && 1269 isr->sav->tdb_authalgxform != NULL && 1270 (m->m_flags & M_AUTHIPDGM) == 0) { 1271 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1272 printf("%s: ESP/AH m_flags:%x\n", __func__, 1273 m->m_flags)); 1274 return (1); 1275 } 1276 break; 1277 case IPPROTO_AH: 1278 need_auth = 1; 1279 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1280 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1281 printf("%s: AH m_flags:%x\n", __func__, 1282 m->m_flags)); 1283 return (1); 1284 } 1285 break; 1286 case IPPROTO_IPCOMP: 1287 /* 1288 * We don't really care, as IPcomp document 1289 * says that we shouldn't compress small 1290 * packets. IPComp policy should always be 1291 * treated as being in "use" level. 1292 */ 1293 break; 1294 } 1295 } 1296 return (0); /* Valid. */ 1297 } 1298 1299 /* 1300 * Non zero return value means security policy DISCARD or policy violation. 1301 */ 1302 static int 1303 ipsec46_in_reject(struct mbuf *m, struct inpcb *inp) 1304 { 1305 struct secpolicy *sp; 1306 int error; 1307 int result; 1308 1309 if (!key_havesp(IPSEC_DIR_INBOUND)) 1310 return 0; 1311 1312 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1313 1314 /* Get SP for this packet. */ 1315 if (inp == NULL) 1316 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, &error); 1317 else 1318 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error); 1319 1320 if (sp != NULL) { 1321 result = ipsec_in_reject(sp, m); 1322 KEY_FREESP(&sp); 1323 } else { 1324 result = 1; /* treat errors as policy violation */ 1325 } 1326 return (result); 1327 } 1328 1329 /* 1330 * Check AH/ESP integrity. 1331 * This function is called from tcp_input(), udp_input(), 1332 * and {ah,esp}4_input for tunnel mode. 1333 */ 1334 int 1335 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1336 { 1337 int result; 1338 1339 result = ipsec46_in_reject(m, inp); 1340 if (result) 1341 IPSECSTAT_INC(ips_in_polvio); 1342 1343 return (result); 1344 } 1345 1346 #ifdef INET6 1347 /* 1348 * Check AH/ESP integrity. 1349 * This function is called from tcp6_input(), udp6_input(), 1350 * and {ah,esp}6_input for tunnel mode. 1351 */ 1352 int 1353 ipsec6_in_reject(struct mbuf *m, struct inpcb *inp) 1354 { 1355 int result; 1356 1357 result = ipsec46_in_reject(m, inp); 1358 if (result) 1359 IPSEC6STAT_INC(ips_in_polvio); 1360 1361 return (result); 1362 } 1363 #endif 1364 1365 /* 1366 * Compute the byte size to be occupied by IPsec header. 1367 * In case it is tunnelled, it includes the size of outer IP header. 1368 * NOTE: SP passed is freed in this function. 1369 */ 1370 static size_t 1371 ipsec_hdrsiz_internal(struct secpolicy *sp) 1372 { 1373 struct ipsecrequest *isr; 1374 size_t size; 1375 1376 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1377 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1378 1379 switch (sp->policy) { 1380 case IPSEC_POLICY_DISCARD: 1381 case IPSEC_POLICY_BYPASS: 1382 case IPSEC_POLICY_NONE: 1383 return (0); 1384 } 1385 1386 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1387 ("invalid policy %u", sp->policy)); 1388 1389 size = 0; 1390 for (isr = sp->req; isr != NULL; isr = isr->next) { 1391 size_t clen = 0; 1392 1393 switch (isr->saidx.proto) { 1394 case IPPROTO_ESP: 1395 clen = esp_hdrsiz(isr->sav); 1396 break; 1397 case IPPROTO_AH: 1398 clen = ah_hdrsiz(isr->sav); 1399 break; 1400 case IPPROTO_IPCOMP: 1401 clen = sizeof(struct ipcomp); 1402 break; 1403 } 1404 1405 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1406 switch (isr->saidx.dst.sa.sa_family) { 1407 case AF_INET: 1408 clen += sizeof(struct ip); 1409 break; 1410 #ifdef INET6 1411 case AF_INET6: 1412 clen += sizeof(struct ip6_hdr); 1413 break; 1414 #endif 1415 default: 1416 ipseclog((LOG_ERR, "%s: unknown AF %d in " 1417 "IPsec tunnel SA\n", __func__, 1418 ((struct sockaddr *)&isr->saidx.dst)->sa_family)); 1419 break; 1420 } 1421 } 1422 size += clen; 1423 } 1424 1425 return (size); 1426 } 1427 1428 /* 1429 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(), 1430 * disabled ip6_ipsec_mtu() and ip6_forward(). 1431 */ 1432 size_t 1433 ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1434 { 1435 struct secpolicy *sp; 1436 int error; 1437 size_t size; 1438 1439 if (!key_havesp(dir)) 1440 return 0; 1441 1442 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1443 1444 /* Get SP for this packet. */ 1445 if (inp == NULL) 1446 sp = ipsec_getpolicybyaddr(m, dir, &error); 1447 else 1448 sp = ipsec_getpolicybysock(m, dir, inp, &error); 1449 1450 if (sp != NULL) { 1451 size = ipsec_hdrsiz_internal(sp); 1452 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1453 printf("%s: size:%lu.\n", __func__, 1454 (unsigned long)size)); 1455 1456 KEY_FREESP(&sp); 1457 } else { 1458 size = 0; /* XXX Should be panic? 1459 * -> No, we are called w/o knowing if 1460 * IPsec processing is needed. */ 1461 } 1462 return (size); 1463 } 1464 1465 /* 1466 * Check the variable replay window. 1467 * ipsec_chkreplay() performs replay check before ICV verification. 1468 * ipsec_updatereplay() updates replay bitmap. This must be called after 1469 * ICV verification (it also performs replay check, which is usually done 1470 * beforehand). 1471 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1472 * 1473 * Based on RFC 2401. 1474 */ 1475 int 1476 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav) 1477 { 1478 const struct secreplay *replay; 1479 u_int32_t diff; 1480 int fr; 1481 u_int32_t wsizeb; /* Constant: bits of window size. */ 1482 int frlast; /* Constant: last frame. */ 1483 1484 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1485 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1486 1487 replay = sav->replay; 1488 1489 if (replay->wsize == 0) 1490 return (1); /* No need to check replay. */ 1491 1492 /* Constant. */ 1493 frlast = replay->wsize - 1; 1494 wsizeb = replay->wsize << 3; 1495 1496 /* Sequence number of 0 is invalid. */ 1497 if (seq == 0) 1498 return (0); 1499 1500 /* First time is always okay. */ 1501 if (replay->count == 0) 1502 return (1); 1503 1504 if (seq > replay->lastseq) { 1505 /* Larger sequences are okay. */ 1506 return (1); 1507 } else { 1508 /* seq is equal or less than lastseq. */ 1509 diff = replay->lastseq - seq; 1510 1511 /* Over range to check, i.e. too old or wrapped. */ 1512 if (diff >= wsizeb) 1513 return (0); 1514 1515 fr = frlast - diff / 8; 1516 1517 /* This packet already seen? */ 1518 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1519 return (0); 1520 1521 /* Out of order but good. */ 1522 return (1); 1523 } 1524 } 1525 1526 /* 1527 * Check replay counter whether to update or not. 1528 * OUT: 0: OK 1529 * 1: NG 1530 */ 1531 int 1532 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav) 1533 { 1534 char buf[128]; 1535 struct secreplay *replay; 1536 u_int32_t diff; 1537 int fr; 1538 u_int32_t wsizeb; /* Constant: bits of window size. */ 1539 int frlast; /* Constant: last frame. */ 1540 1541 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1542 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1543 1544 replay = sav->replay; 1545 1546 if (replay->wsize == 0) 1547 goto ok; /* No need to check replay. */ 1548 1549 /* Constant. */ 1550 frlast = replay->wsize - 1; 1551 wsizeb = replay->wsize << 3; 1552 1553 /* Sequence number of 0 is invalid. */ 1554 if (seq == 0) 1555 return (1); 1556 1557 /* First time. */ 1558 if (replay->count == 0) { 1559 replay->lastseq = seq; 1560 bzero(replay->bitmap, replay->wsize); 1561 (replay->bitmap)[frlast] = 1; 1562 goto ok; 1563 } 1564 1565 if (seq > replay->lastseq) { 1566 /* seq is larger than lastseq. */ 1567 diff = seq - replay->lastseq; 1568 1569 /* New larger sequence number. */ 1570 if (diff < wsizeb) { 1571 /* In window. */ 1572 /* Set bit for this packet. */ 1573 vshiftl(replay->bitmap, diff, replay->wsize); 1574 (replay->bitmap)[frlast] |= 1; 1575 } else { 1576 /* This packet has a "way larger". */ 1577 bzero(replay->bitmap, replay->wsize); 1578 (replay->bitmap)[frlast] = 1; 1579 } 1580 replay->lastseq = seq; 1581 1582 /* Larger is good. */ 1583 } else { 1584 /* seq is equal or less than lastseq. */ 1585 diff = replay->lastseq - seq; 1586 1587 /* Over range to check, i.e. too old or wrapped. */ 1588 if (diff >= wsizeb) 1589 return (1); 1590 1591 fr = frlast - diff / 8; 1592 1593 /* This packet already seen? */ 1594 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1595 return (1); 1596 1597 /* Mark as seen. */ 1598 (replay->bitmap)[fr] |= (1 << (diff % 8)); 1599 1600 /* Out of order but good. */ 1601 } 1602 1603 ok: 1604 if (replay->count == ~0) { 1605 1606 /* Set overflow flag. */ 1607 replay->overflow++; 1608 1609 /* Don't increment, no more packets accepted. */ 1610 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 1611 return (1); 1612 1613 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1614 __func__, replay->overflow, 1615 ipsec_logsastr(sav, buf, sizeof(buf)))); 1616 } 1617 1618 replay->count++; 1619 1620 return (0); 1621 } 1622 1623 /* 1624 * Shift variable length buffer to left. 1625 * IN: bitmap: pointer to the buffer 1626 * nbit: the number of to shift. 1627 * wsize: buffer size (bytes). 1628 */ 1629 static void 1630 vshiftl(unsigned char *bitmap, int nbit, int wsize) 1631 { 1632 int s, j, i; 1633 unsigned char over; 1634 1635 for (j = 0; j < nbit; j += 8) { 1636 s = (nbit - j < 8) ? (nbit - j): 8; 1637 bitmap[0] <<= s; 1638 for (i = 1; i < wsize; i++) { 1639 over = (bitmap[i] >> (8 - s)); 1640 bitmap[i] <<= s; 1641 bitmap[i-1] |= over; 1642 } 1643 } 1644 } 1645 1646 /* Return a printable string for the address. */ 1647 char* 1648 ipsec_address(union sockaddr_union* sa, char *buf, socklen_t size) 1649 { 1650 1651 switch (sa->sa.sa_family) { 1652 #ifdef INET 1653 case AF_INET: 1654 return (inet_ntop(AF_INET, &sa->sin.sin_addr, buf, size)); 1655 #endif /* INET */ 1656 #ifdef INET6 1657 case AF_INET6: 1658 return (inet_ntop(AF_INET6, &sa->sin6.sin6_addr, buf, size)); 1659 #endif /* INET6 */ 1660 default: 1661 return ("(unknown address family)"); 1662 } 1663 } 1664 1665 char * 1666 ipsec_logsastr(struct secasvar *sav, char *buf, size_t size) 1667 { 1668 char sbuf[INET6_ADDRSTRLEN], dbuf[INET6_ADDRSTRLEN]; 1669 1670 IPSEC_ASSERT(sav->sah->saidx.src.sa.sa_family == 1671 sav->sah->saidx.dst.sa.sa_family, ("address family mismatch")); 1672 1673 snprintf(buf, size, "SA(SPI=%08lx src=%s dst=%s)", 1674 (u_long)ntohl(sav->spi), 1675 ipsec_address(&sav->sah->saidx.src, sbuf, sizeof(sbuf)), 1676 ipsec_address(&sav->sah->saidx.dst, dbuf, sizeof(dbuf))); 1677 return (buf); 1678 } 1679 1680 void 1681 ipsec_dumpmbuf(struct mbuf *m) 1682 { 1683 int totlen; 1684 int i; 1685 u_char *p; 1686 1687 totlen = 0; 1688 printf("---\n"); 1689 while (m) { 1690 p = mtod(m, u_char *); 1691 for (i = 0; i < m->m_len; i++) { 1692 printf("%02x ", p[i]); 1693 totlen++; 1694 if (totlen % 16 == 0) 1695 printf("\n"); 1696 } 1697 m = m->m_next; 1698 } 1699 if (totlen % 16 != 0) 1700 printf("\n"); 1701 printf("---\n"); 1702 } 1703 1704 static void 1705 def_policy_init(const void *unused __unused) 1706 { 1707 1708 bzero(&V_def_policy, sizeof(struct secpolicy)); 1709 V_def_policy.policy = IPSEC_POLICY_NONE; 1710 V_def_policy.refcnt = 1; 1711 } 1712 VNET_SYSINIT(def_policy_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, 1713 def_policy_init, NULL); 1714 1715 1716 /* XXX This stuff doesn't belong here... */ 1717 1718 static struct xformsw* xforms = NULL; 1719 1720 /* 1721 * Register a transform; typically at system startup. 1722 */ 1723 void 1724 xform_register(struct xformsw* xsp) 1725 { 1726 1727 xsp->xf_next = xforms; 1728 xforms = xsp; 1729 } 1730 1731 /* 1732 * Initialize transform support in an sav. 1733 */ 1734 int 1735 xform_init(struct secasvar *sav, int xftype) 1736 { 1737 struct xformsw *xsp; 1738 1739 if (sav->tdb_xform != NULL) /* Previously initialized. */ 1740 return (0); 1741 for (xsp = xforms; xsp; xsp = xsp->xf_next) 1742 if (xsp->xf_type == xftype) 1743 return ((*xsp->xf_init)(sav, xsp)); 1744 return (EINVAL); 1745 } 1746