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/time.h> 52 #include <sys/kernel.h> 53 #include <sys/syslog.h> 54 #include <sys/sysctl.h> 55 #include <sys/proc.h> 56 #include <sys/vimage.h> 57 58 #include <net/if.h> 59 #include <net/route.h> 60 61 #include <netinet/in.h> 62 #include <netinet/in_systm.h> 63 #include <netinet/ip.h> 64 #include <netinet/ip_var.h> 65 #include <netinet/in_var.h> 66 #include <netinet/udp.h> 67 #include <netinet/udp_var.h> 68 #include <netinet/tcp.h> 69 #include <netinet/udp.h> 70 71 #include <netinet/ip6.h> 72 #ifdef INET6 73 #include <netinet6/ip6_var.h> 74 #endif 75 #include <netinet/in_pcb.h> 76 #ifdef INET6 77 #include <netinet/icmp6.h> 78 #endif 79 80 #include <sys/types.h> 81 #include <netipsec/ipsec.h> 82 #ifdef INET6 83 #include <netipsec/ipsec6.h> 84 #endif 85 #include <netipsec/ah_var.h> 86 #include <netipsec/esp_var.h> 87 #include <netipsec/ipcomp.h> /*XXX*/ 88 #include <netipsec/ipcomp_var.h> 89 90 #include <netipsec/key.h> 91 #include <netipsec/keydb.h> 92 #include <netipsec/key_debug.h> 93 94 #include <netipsec/xform.h> 95 96 #include <machine/in_cksum.h> 97 98 #include <opencrypto/cryptodev.h> 99 100 #ifndef VIMAGE 101 #ifndef VIMAGE_GLOBALS 102 struct vnet_ipsec vnet_ipsec_0; 103 #endif 104 #endif 105 106 static int ipsec_iattach(const void *); 107 108 #ifdef VIMAGE_GLOBALS 109 /* NB: name changed so netstat doesn't use it. */ 110 struct ipsecstat ipsec4stat; 111 struct secpolicy ip4_def_policy; 112 int ipsec_debug; 113 int ip4_ah_offsetmask; 114 int ip4_ipsec_dfbit; 115 int ip4_esp_trans_deflev; 116 int ip4_esp_net_deflev; 117 int ip4_ah_trans_deflev; 118 int ip4_ah_net_deflev; 119 int ip4_ipsec_ecn; 120 int ip4_esp_randpad; 121 /* 122 * Crypto support requirements: 123 * 124 * 1 require hardware support 125 * -1 require software support 126 * 0 take anything 127 */ 128 int crypto_support; 129 #endif /* VIMAGE_GLOBALS */ 130 131 SYSCTL_DECL(_net_inet_ipsec); 132 133 /* net.inet.ipsec */ 134 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_POLICY, 135 def_policy, CTLFLAG_RW, ip4_def_policy.policy, 0, 136 "IPsec default policy."); 137 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, 138 esp_trans_deflev, CTLFLAG_RW, ip4_esp_trans_deflev, 0, 139 "Default ESP transport mode level"); 140 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, 141 esp_net_deflev, CTLFLAG_RW, ip4_esp_net_deflev, 0, 142 "Default ESP tunnel mode level."); 143 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, 144 ah_trans_deflev, CTLFLAG_RW, ip4_ah_trans_deflev, 0, 145 "AH transfer mode default level."); 146 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, 147 ah_net_deflev, CTLFLAG_RW, ip4_ah_net_deflev, 0, 148 "AH tunnel mode default level."); 149 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_AH_CLEARTOS, 150 ah_cleartos, CTLFLAG_RW, ah_cleartos, 0, 151 "If set clear type-of-service field when doing AH computation."); 152 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, 153 ah_offsetmask, CTLFLAG_RW, ip4_ah_offsetmask, 0, 154 "If not set clear offset field mask when doing AH computation."); 155 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DFBIT, 156 dfbit, CTLFLAG_RW, ip4_ipsec_dfbit, 0, 157 "Do not fragment bit on encap."); 158 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_ECN, 159 ecn, CTLFLAG_RW, ip4_ipsec_ecn, 0, 160 "Explicit Congestion Notification handling."); 161 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEBUG, 162 debug, CTLFLAG_RW, ipsec_debug, 0, 163 "Enable IPsec debugging output when set."); 164 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, OID_AUTO, 165 crypto_support, CTLFLAG_RW, crypto_support,0, 166 "Crypto driver selection."); 167 SYSCTL_V_STRUCT(V_NET, vnet_ipsec, _net_inet_ipsec, OID_AUTO, 168 ipsecstats, CTLFLAG_RD, ipsec4stat, ipsecstat, 169 "IPsec IPv4 statistics."); 170 171 #ifdef REGRESSION 172 #ifdef VIMAGE_GLOBALS 173 int ipsec_replay; 174 int ipsec_integrity; 175 #endif 176 /* 177 * When set to 1, IPsec will send packets with the same sequence number. 178 * This allows to verify if the other side has proper replay attacks detection. 179 */ 180 SYSCTL_V_INT(V_NET, vnet_ipsec,_net_inet_ipsec, OID_AUTO, test_replay, 181 CTLFLAG_RW, ipsec_replay, 0, "Emulate replay attack"); 182 /* 183 * When set 1, IPsec will send packets with corrupted HMAC. 184 * This allows to verify if the other side properly detects modified packets. 185 */ 186 SYSCTL_V_INT(V_NET, vnet_ipsec,_net_inet_ipsec, OID_AUTO, test_integrity, 187 CTLFLAG_RW, ipsec_integrity, 0, "Emulate man-in-the-middle attack"); 188 #endif 189 190 #ifdef INET6 191 #ifdef VIMAGE_GLOBALS 192 struct ipsecstat ipsec6stat; 193 int ip6_esp_trans_deflev; 194 int ip6_esp_net_deflev; 195 int ip6_ah_trans_deflev; 196 int ip6_ah_net_deflev; 197 int ip6_ipsec_ecn; 198 #endif 199 200 SYSCTL_DECL(_net_inet6_ipsec6); 201 202 /* net.inet6.ipsec6 */ 203 #ifdef COMPAT_KAME 204 SYSCTL_OID(_net_inet6_ipsec6, IPSECCTL_STATS, stats, CTLFLAG_RD, 205 0, 0, compat_ipsecstats_sysctl, "S", "IPsec IPv6 statistics."); 206 #endif /* COMPAT_KAME */ 207 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_POLICY, 208 def_policy, CTLFLAG_RW, ip4_def_policy.policy, 0, 209 "IPsec default policy."); 210 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV, 211 esp_trans_deflev, CTLFLAG_RW, ip6_esp_trans_deflev, 0, 212 "Default ESP transport mode level."); 213 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV, 214 esp_net_deflev, CTLFLAG_RW, ip6_esp_net_deflev, 0, 215 "Default ESP tunnel mode level."); 216 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV, 217 ah_trans_deflev, CTLFLAG_RW, ip6_ah_trans_deflev, 0, 218 "AH transfer mode default level."); 219 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV, 220 ah_net_deflev, CTLFLAG_RW, ip6_ah_net_deflev, 0, 221 "AH tunnel mode default level."); 222 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_ECN, 223 ecn, CTLFLAG_RW, ip6_ipsec_ecn, 0, 224 "Explicit Congestion Notification handling."); 225 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEBUG, 226 debug, CTLFLAG_RW, ipsec_debug, 0, 227 "Enable IPsec debugging output when set."); 228 SYSCTL_V_STRUCT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_STATS, 229 ipsecstats, CTLFLAG_RD, ipsec6stat, ipsecstat, 230 "IPsec IPv6 statistics."); 231 #endif /* INET6 */ 232 233 static int ipsec_setspidx_inpcb __P((struct mbuf *, struct inpcb *)); 234 static int ipsec_setspidx __P((struct mbuf *, struct secpolicyindex *, int)); 235 static void ipsec4_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 236 static int ipsec4_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 237 #ifdef INET6 238 static void ipsec6_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 239 static int ipsec6_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 240 #endif 241 static void ipsec_delpcbpolicy __P((struct inpcbpolicy *)); 242 static struct secpolicy *ipsec_deepcopy_policy __P((struct secpolicy *src)); 243 static void vshiftl __P((unsigned char *, int, int)); 244 245 MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy"); 246 247 #ifndef VIMAGE_GLOBALS 248 static const vnet_modinfo_t vnet_ipsec_modinfo = { 249 .vmi_id = VNET_MOD_IPSEC, 250 .vmi_name = "ipsec", 251 .vmi_size = sizeof(struct vnet_ipsec), 252 .vmi_dependson = VNET_MOD_INET, /* XXX revisit - INET6 ? */ 253 .vmi_iattach = ipsec_iattach 254 }; 255 #endif /* !VIMAGE_GLOBALS */ 256 257 void 258 ipsec_init(void) 259 { 260 INIT_VNET_IPSEC(curvnet); 261 262 #ifdef IPSEC_DEBUG 263 V_ipsec_debug = 1; 264 #else 265 V_ipsec_debug = 0; 266 #endif 267 268 V_ip4_ah_offsetmask = 0; /* maybe IP_DF? */ 269 V_ip4_ipsec_dfbit = 0; /* DF bit on encap. 0: clear 1: set 2: copy */ 270 V_ip4_esp_trans_deflev = IPSEC_LEVEL_USE; 271 V_ip4_esp_net_deflev = IPSEC_LEVEL_USE; 272 V_ip4_ah_trans_deflev = IPSEC_LEVEL_USE; 273 V_ip4_ah_net_deflev = IPSEC_LEVEL_USE; 274 V_ip4_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 275 V_ip4_esp_randpad = -1; 276 277 V_crypto_support = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE; 278 279 #ifdef REGRESSION 280 V_ipsec_replay = 0; 281 V_ipsec_integrity = 0; 282 #endif 283 284 #ifdef INET6 285 V_ip6_esp_trans_deflev = IPSEC_LEVEL_USE; 286 V_ip6_esp_net_deflev = IPSEC_LEVEL_USE; 287 V_ip6_ah_trans_deflev = IPSEC_LEVEL_USE; 288 V_ip6_ah_net_deflev = IPSEC_LEVEL_USE; 289 V_ip6_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 290 #endif 291 } 292 293 /* 294 * Return a held reference to the default SP. 295 */ 296 static struct secpolicy * 297 key_allocsp_default(const char* where, int tag) 298 { 299 INIT_VNET_IPSEC(curvnet); 300 struct secpolicy *sp; 301 302 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 303 printf("DP key_allocsp_default from %s:%u\n", where, tag)); 304 305 sp = &V_ip4_def_policy; 306 if (sp->policy != IPSEC_POLICY_DISCARD && 307 sp->policy != IPSEC_POLICY_NONE) { 308 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n", 309 sp->policy, IPSEC_POLICY_NONE)); 310 sp->policy = IPSEC_POLICY_NONE; 311 } 312 key_addref(sp); 313 314 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 315 printf("DP key_allocsp_default returns SP:%p (%u)\n", 316 sp, sp->refcnt)); 317 return (sp); 318 } 319 #define KEY_ALLOCSP_DEFAULT() \ 320 key_allocsp_default(__FILE__, __LINE__) 321 322 /* 323 * For OUTBOUND packet having a socket. Searching SPD for packet, 324 * and return a pointer to SP. 325 * OUT: NULL: no apropreate SP found, the following value is set to error. 326 * 0 : bypass 327 * EACCES : discard packet. 328 * ENOENT : ipsec_acquire() in progress, maybe. 329 * others : error occured. 330 * others: a pointer to SP 331 * 332 * NOTE: IPv6 mapped adddress concern is implemented here. 333 */ 334 struct secpolicy * 335 ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir) 336 { 337 struct secpolicy *sp; 338 339 IPSEC_ASSERT(tdbi != NULL, ("null tdbi")); 340 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 341 ("invalid direction %u", dir)); 342 343 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir); 344 if (sp == NULL) /*XXX????*/ 345 sp = KEY_ALLOCSP_DEFAULT(); 346 IPSEC_ASSERT(sp != NULL, ("null SP")); 347 return (sp); 348 } 349 350 /* 351 * For OUTBOUND packet having a socket. Searching SPD for packet, 352 * and return a pointer to SP. 353 * OUT: NULL: no apropreate SP found, the following value is set to error. 354 * 0 : bypass 355 * EACCES : discard packet. 356 * ENOENT : ipsec_acquire() in progress, maybe. 357 * others : error occured. 358 * others: a pointer to SP 359 * 360 * NOTE: IPv6 mapped adddress concern is implemented here. 361 */ 362 static struct secpolicy * 363 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb *inp, int *error) 364 { 365 INIT_VNET_IPSEC(curvnet); 366 struct inpcbpolicy *pcbsp; 367 struct secpolicy *currsp = NULL; /* Policy on socket. */ 368 struct secpolicy *sp; 369 370 IPSEC_ASSERT(m != NULL, ("null mbuf")); 371 IPSEC_ASSERT(inp != NULL, ("null inpcb")); 372 IPSEC_ASSERT(error != NULL, ("null error")); 373 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 374 ("invalid direction %u", dir)); 375 376 /* Set spidx in pcb. */ 377 *error = ipsec_setspidx_inpcb(m, inp); 378 if (*error) 379 return (NULL); 380 381 pcbsp = inp->inp_sp; 382 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp")); 383 switch (dir) { 384 case IPSEC_DIR_INBOUND: 385 currsp = pcbsp->sp_in; 386 break; 387 case IPSEC_DIR_OUTBOUND: 388 currsp = pcbsp->sp_out; 389 break; 390 } 391 IPSEC_ASSERT(currsp != NULL, ("null currsp")); 392 393 if (pcbsp->priv) { /* When privilieged socket. */ 394 switch (currsp->policy) { 395 case IPSEC_POLICY_BYPASS: 396 case IPSEC_POLICY_IPSEC: 397 key_addref(currsp); 398 sp = currsp; 399 break; 400 401 case IPSEC_POLICY_ENTRUST: 402 /* Look for a policy in SPD. */ 403 sp = KEY_ALLOCSP(&currsp->spidx, dir); 404 if (sp == NULL) /* No SP found. */ 405 sp = KEY_ALLOCSP_DEFAULT(); 406 break; 407 408 default: 409 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n", 410 __func__, currsp->policy)); 411 *error = EINVAL; 412 return (NULL); 413 } 414 } else { /* Unpriv, SPD has policy. */ 415 sp = KEY_ALLOCSP(&currsp->spidx, dir); 416 if (sp == NULL) { /* No SP found. */ 417 switch (currsp->policy) { 418 case IPSEC_POLICY_BYPASS: 419 ipseclog((LOG_ERR, "%s: Illegal policy for " 420 "non-priviliged defined %d\n", 421 __func__, currsp->policy)); 422 *error = EINVAL; 423 return (NULL); 424 425 case IPSEC_POLICY_ENTRUST: 426 sp = KEY_ALLOCSP_DEFAULT(); 427 break; 428 429 case IPSEC_POLICY_IPSEC: 430 key_addref(currsp); 431 sp = currsp; 432 break; 433 434 default: 435 ipseclog((LOG_ERR, "%s: Invalid policy for " 436 "PCB %d\n", __func__, currsp->policy)); 437 *error = EINVAL; 438 return (NULL); 439 } 440 } 441 } 442 IPSEC_ASSERT(sp != NULL, 443 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy)); 444 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 445 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n", 446 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt)); 447 return (sp); 448 } 449 450 /* 451 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 452 * and return a pointer to SP. 453 * OUT: positive: a pointer to the entry for security policy leaf matched. 454 * NULL: no apropreate SP found, the following value is set to error. 455 * 0 : bypass 456 * EACCES : discard packet. 457 * ENOENT : ipsec_acquire() in progress, maybe. 458 * others : error occured. 459 */ 460 struct secpolicy * 461 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 462 { 463 INIT_VNET_IPSEC(curvnet); 464 struct secpolicyindex spidx; 465 struct secpolicy *sp; 466 467 IPSEC_ASSERT(m != NULL, ("null mbuf")); 468 IPSEC_ASSERT(error != NULL, ("null error")); 469 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 470 ("invalid direction %u", dir)); 471 472 sp = NULL; 473 if (key_havesp(dir)) { 474 /* Make an index to look for a policy. */ 475 *error = ipsec_setspidx(m, &spidx, 476 (flag & IP_FORWARDING) ? 0 : 1); 477 if (*error != 0) { 478 DPRINTF(("%s: setpidx failed, dir %u flag %u\n", 479 __func__, dir, flag)); 480 return (NULL); 481 } 482 spidx.dir = dir; 483 484 sp = KEY_ALLOCSP(&spidx, dir); 485 } 486 if (sp == NULL) /* No SP found, use system default. */ 487 sp = KEY_ALLOCSP_DEFAULT(); 488 IPSEC_ASSERT(sp != NULL, ("null SP")); 489 return (sp); 490 } 491 492 struct secpolicy * 493 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 494 struct inpcb *inp) 495 { 496 INIT_VNET_IPSEC(curvnet); 497 struct secpolicy *sp; 498 499 *error = 0; 500 if (inp == NULL) 501 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 502 else 503 sp = ipsec_getpolicybysock(m, dir, inp, error); 504 if (sp == NULL) { 505 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error")); 506 V_ipsec4stat.ips_out_inval++; 507 return (NULL); 508 } 509 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error)); 510 switch (sp->policy) { 511 case IPSEC_POLICY_ENTRUST: 512 default: 513 printf("%s: invalid policy %u\n", __func__, sp->policy); 514 /* FALLTHROUGH */ 515 case IPSEC_POLICY_DISCARD: 516 V_ipsec4stat.ips_out_polvio++; 517 *error = -EINVAL; /* Packet is discarded by caller. */ 518 break; 519 case IPSEC_POLICY_BYPASS: 520 case IPSEC_POLICY_NONE: 521 KEY_FREESP(&sp); 522 sp = NULL; /* NB: force NULL result. */ 523 break; 524 case IPSEC_POLICY_IPSEC: 525 if (sp->req == NULL) /* Acquire a SA. */ 526 *error = key_spdacquire(sp); 527 break; 528 } 529 if (*error != 0) { 530 KEY_FREESP(&sp); 531 sp = NULL; 532 } 533 return (sp); 534 } 535 536 static int 537 ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp) 538 { 539 int error; 540 541 IPSEC_ASSERT(inp != NULL, ("null inp")); 542 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 543 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL, 544 ("null sp_in || sp_out")); 545 546 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1); 547 if (error == 0) { 548 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 549 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx; 550 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 551 } else { 552 bzero(&inp->inp_sp->sp_in->spidx, 553 sizeof (inp->inp_sp->sp_in->spidx)); 554 bzero(&inp->inp_sp->sp_out->spidx, 555 sizeof (inp->inp_sp->sp_in->spidx)); 556 } 557 return (error); 558 } 559 560 /* 561 * Configure security policy index (src/dst/proto/sport/dport) 562 * by looking at the content of mbuf. 563 * The caller is responsible for error recovery (like clearing up spidx). 564 */ 565 static int 566 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 567 { 568 INIT_VNET_IPSEC(curvnet); 569 struct ip *ip = NULL; 570 struct ip ipbuf; 571 u_int v; 572 struct mbuf *n; 573 int len; 574 int error; 575 576 IPSEC_ASSERT(m != NULL, ("null mbuf")); 577 578 /* 579 * Validate m->m_pkthdr.len. We see incorrect length if we 580 * mistakenly call this function with inconsistent mbuf chain 581 * (like 4.4BSD tcp/udp processing). XXX Should we panic here? 582 */ 583 len = 0; 584 for (n = m; n; n = n->m_next) 585 len += n->m_len; 586 if (m->m_pkthdr.len != len) { 587 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 588 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n", 589 __func__, len, m->m_pkthdr.len)); 590 return (EINVAL); 591 } 592 593 if (m->m_pkthdr.len < sizeof(struct ip)) { 594 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 595 printf("%s: pkthdr len(%d) too small (v4), ignored.\n", 596 __func__, m->m_pkthdr.len)); 597 return (EINVAL); 598 } 599 600 if (m->m_len >= sizeof(*ip)) 601 ip = mtod(m, struct ip *); 602 else { 603 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf); 604 ip = &ipbuf; 605 } 606 #ifdef _IP_VHL 607 v = _IP_VHL_V(ip->ip_vhl); 608 #else 609 v = ip->ip_v; 610 #endif 611 switch (v) { 612 case 4: 613 error = ipsec4_setspidx_ipaddr(m, spidx); 614 if (error) 615 return (error); 616 ipsec4_get_ulp(m, spidx, needport); 617 return (0); 618 #ifdef INET6 619 case 6: 620 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 621 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 622 printf("%s: pkthdr len(%d) too small (v6), " 623 "ignored\n", __func__, m->m_pkthdr.len)); 624 return (EINVAL); 625 } 626 error = ipsec6_setspidx_ipaddr(m, spidx); 627 if (error) 628 return (error); 629 ipsec6_get_ulp(m, spidx, needport); 630 return (0); 631 #endif 632 default: 633 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 634 printf("%s: " "unknown IP version %u, ignored.\n", 635 __func__, v)); 636 return (EINVAL); 637 } 638 } 639 640 static void 641 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 642 { 643 u_int8_t nxt; 644 int off; 645 646 /* Sanity check. */ 647 IPSEC_ASSERT(m != NULL, ("null mbuf")); 648 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short")); 649 650 /* NB: ip_input() flips it into host endian. XXX Need more checking. */ 651 if (m->m_len < sizeof (struct ip)) { 652 struct ip *ip = mtod(m, struct ip *); 653 if (ip->ip_off & (IP_MF | IP_OFFMASK)) 654 goto done; 655 #ifdef _IP_VHL 656 off = _IP_VHL_HL(ip->ip_vhl) << 2; 657 #else 658 off = ip->ip_hl << 2; 659 #endif 660 nxt = ip->ip_p; 661 } else { 662 struct ip ih; 663 664 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih); 665 if (ih.ip_off & (IP_MF | IP_OFFMASK)) 666 goto done; 667 #ifdef _IP_VHL 668 off = _IP_VHL_HL(ih.ip_vhl) << 2; 669 #else 670 off = ih.ip_hl << 2; 671 #endif 672 nxt = ih.ip_p; 673 } 674 675 while (off < m->m_pkthdr.len) { 676 struct ip6_ext ip6e; 677 struct tcphdr th; 678 struct udphdr uh; 679 680 switch (nxt) { 681 case IPPROTO_TCP: 682 spidx->ul_proto = nxt; 683 if (!needport) 684 goto done_proto; 685 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 686 goto done; 687 m_copydata(m, off, sizeof (th), (caddr_t) &th); 688 spidx->src.sin.sin_port = th.th_sport; 689 spidx->dst.sin.sin_port = th.th_dport; 690 return; 691 case IPPROTO_UDP: 692 spidx->ul_proto = nxt; 693 if (!needport) 694 goto done_proto; 695 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 696 goto done; 697 m_copydata(m, off, sizeof (uh), (caddr_t) &uh); 698 spidx->src.sin.sin_port = uh.uh_sport; 699 spidx->dst.sin.sin_port = uh.uh_dport; 700 return; 701 case IPPROTO_AH: 702 if (off + sizeof(ip6e) > m->m_pkthdr.len) 703 goto done; 704 /* XXX Sigh, this works but is totally bogus. */ 705 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e); 706 off += (ip6e.ip6e_len + 2) << 2; 707 nxt = ip6e.ip6e_nxt; 708 break; 709 case IPPROTO_ICMP: 710 default: 711 /* XXX Intermediate headers??? */ 712 spidx->ul_proto = nxt; 713 goto done_proto; 714 } 715 } 716 done: 717 spidx->ul_proto = IPSEC_ULPROTO_ANY; 718 done_proto: 719 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 720 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 721 } 722 723 /* Assumes that m is sane. */ 724 static int 725 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 726 { 727 static const struct sockaddr_in template = { 728 sizeof (struct sockaddr_in), 729 AF_INET, 730 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 731 }; 732 733 spidx->src.sin = template; 734 spidx->dst.sin = template; 735 736 if (m->m_len < sizeof (struct ip)) { 737 m_copydata(m, offsetof(struct ip, ip_src), 738 sizeof (struct in_addr), 739 (caddr_t) &spidx->src.sin.sin_addr); 740 m_copydata(m, offsetof(struct ip, ip_dst), 741 sizeof (struct in_addr), 742 (caddr_t) &spidx->dst.sin.sin_addr); 743 } else { 744 struct ip *ip = mtod(m, struct ip *); 745 spidx->src.sin.sin_addr = ip->ip_src; 746 spidx->dst.sin.sin_addr = ip->ip_dst; 747 } 748 749 spidx->prefs = sizeof(struct in_addr) << 3; 750 spidx->prefd = sizeof(struct in_addr) << 3; 751 752 return (0); 753 } 754 755 #ifdef INET6 756 static void 757 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 758 { 759 INIT_VNET_IPSEC(curvnet); 760 int off, nxt; 761 struct tcphdr th; 762 struct udphdr uh; 763 struct icmp6_hdr ih; 764 765 /* Sanity check. */ 766 if (m == NULL) 767 panic("%s: NULL pointer was passed.\n", __func__); 768 769 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 770 printf("%s:\n", __func__); kdebug_mbuf(m)); 771 772 /* Set default. */ 773 spidx->ul_proto = IPSEC_ULPROTO_ANY; 774 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 775 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 776 777 nxt = -1; 778 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 779 if (off < 0 || m->m_pkthdr.len < off) 780 return; 781 782 switch (nxt) { 783 case IPPROTO_TCP: 784 spidx->ul_proto = nxt; 785 if (!needport) 786 break; 787 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 788 break; 789 m_copydata(m, off, sizeof(th), (caddr_t)&th); 790 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 791 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 792 break; 793 case IPPROTO_UDP: 794 spidx->ul_proto = nxt; 795 if (!needport) 796 break; 797 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 798 break; 799 m_copydata(m, off, sizeof(uh), (caddr_t)&uh); 800 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 801 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 802 break; 803 case IPPROTO_ICMPV6: 804 spidx->ul_proto = nxt; 805 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 806 break; 807 m_copydata(m, off, sizeof(ih), (caddr_t)&ih); 808 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 809 htons((uint16_t)ih.icmp6_type); 810 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 811 htons((uint16_t)ih.icmp6_code); 812 break; 813 default: 814 /* XXX Intermediate headers??? */ 815 spidx->ul_proto = nxt; 816 break; 817 } 818 } 819 820 /* Assumes that m is sane. */ 821 static int 822 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 823 { 824 struct ip6_hdr *ip6 = NULL; 825 struct ip6_hdr ip6buf; 826 struct sockaddr_in6 *sin6; 827 828 if (m->m_len >= sizeof(*ip6)) 829 ip6 = mtod(m, struct ip6_hdr *); 830 else { 831 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf); 832 ip6 = &ip6buf; 833 } 834 835 sin6 = (struct sockaddr_in6 *)&spidx->src; 836 bzero(sin6, sizeof(*sin6)); 837 sin6->sin6_family = AF_INET6; 838 sin6->sin6_len = sizeof(struct sockaddr_in6); 839 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src)); 840 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 841 sin6->sin6_addr.s6_addr16[1] = 0; 842 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 843 } 844 spidx->prefs = sizeof(struct in6_addr) << 3; 845 846 sin6 = (struct sockaddr_in6 *)&spidx->dst; 847 bzero(sin6, sizeof(*sin6)); 848 sin6->sin6_family = AF_INET6; 849 sin6->sin6_len = sizeof(struct sockaddr_in6); 850 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst)); 851 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 852 sin6->sin6_addr.s6_addr16[1] = 0; 853 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 854 } 855 spidx->prefd = sizeof(struct in6_addr) << 3; 856 857 return (0); 858 } 859 #endif 860 861 static void 862 ipsec_delpcbpolicy(struct inpcbpolicy *p) 863 { 864 865 free(p, M_IPSEC_INPCB); 866 } 867 868 /* Initialize policy in PCB. */ 869 int 870 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp) 871 { 872 INIT_VNET_IPSEC(curvnet); 873 struct inpcbpolicy *new; 874 875 /* Sanity check. */ 876 if (so == NULL || pcb_sp == NULL) 877 panic("%s: NULL pointer was passed.\n", __func__); 878 879 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy), 880 M_IPSEC_INPCB, M_NOWAIT|M_ZERO); 881 if (new == NULL) { 882 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 883 return (ENOBUFS); 884 } 885 886 new->priv = IPSEC_IS_PRIVILEGED_SO(so); 887 888 if ((new->sp_in = KEY_NEWSP()) == NULL) { 889 ipsec_delpcbpolicy(new); 890 return (ENOBUFS); 891 } 892 new->sp_in->state = IPSEC_SPSTATE_ALIVE; 893 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 894 895 if ((new->sp_out = KEY_NEWSP()) == NULL) { 896 KEY_FREESP(&new->sp_in); 897 ipsec_delpcbpolicy(new); 898 return (ENOBUFS); 899 } 900 new->sp_out->state = IPSEC_SPSTATE_ALIVE; 901 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 902 903 *pcb_sp = new; 904 905 return (0); 906 } 907 908 /* Copy old IPsec policy into new. */ 909 int 910 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new) 911 { 912 struct secpolicy *sp; 913 914 sp = ipsec_deepcopy_policy(old->sp_in); 915 if (sp) { 916 KEY_FREESP(&new->sp_in); 917 new->sp_in = sp; 918 } else 919 return (ENOBUFS); 920 921 sp = ipsec_deepcopy_policy(old->sp_out); 922 if (sp) { 923 KEY_FREESP(&new->sp_out); 924 new->sp_out = sp; 925 } else 926 return (ENOBUFS); 927 928 new->priv = old->priv; 929 930 return (0); 931 } 932 933 struct ipsecrequest * 934 ipsec_newisr(void) 935 { 936 struct ipsecrequest *p; 937 938 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO); 939 if (p != NULL) 940 IPSECREQUEST_LOCK_INIT(p); 941 return (p); 942 } 943 944 void 945 ipsec_delisr(struct ipsecrequest *p) 946 { 947 948 IPSECREQUEST_LOCK_DESTROY(p); 949 free(p, M_IPSEC_SR); 950 } 951 952 /* Deep-copy a policy in PCB. */ 953 static struct secpolicy * 954 ipsec_deepcopy_policy(struct secpolicy *src) 955 { 956 struct ipsecrequest *newchain = NULL; 957 struct ipsecrequest *p; 958 struct ipsecrequest **q; 959 struct ipsecrequest *r; 960 struct secpolicy *dst; 961 962 if (src == NULL) 963 return (NULL); 964 dst = KEY_NEWSP(); 965 if (dst == NULL) 966 return (NULL); 967 968 /* 969 * Deep-copy IPsec request chain. This is required since struct 970 * ipsecrequest is not reference counted. 971 */ 972 q = &newchain; 973 for (p = src->req; p; p = p->next) { 974 *q = ipsec_newisr(); 975 if (*q == NULL) 976 goto fail; 977 (*q)->saidx.proto = p->saidx.proto; 978 (*q)->saidx.mode = p->saidx.mode; 979 (*q)->level = p->level; 980 (*q)->saidx.reqid = p->saidx.reqid; 981 982 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src)); 983 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst)); 984 985 (*q)->sp = dst; 986 987 q = &((*q)->next); 988 } 989 990 dst->req = newchain; 991 dst->state = src->state; 992 dst->policy = src->policy; 993 /* Do not touch the refcnt fields. */ 994 995 return (dst); 996 997 fail: 998 for (p = newchain; p; p = r) { 999 r = p->next; 1000 ipsec_delisr(p); 1001 p = NULL; 1002 } 1003 return (NULL); 1004 } 1005 1006 /* Set policy and IPsec request if present. */ 1007 static int 1008 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname, 1009 caddr_t request, size_t len, struct ucred *cred) 1010 { 1011 INIT_VNET_IPSEC(curvnet); 1012 struct sadb_x_policy *xpl; 1013 struct secpolicy *newsp = NULL; 1014 int error; 1015 1016 /* Sanity check. */ 1017 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL) 1018 return (EINVAL); 1019 if (len < sizeof(*xpl)) 1020 return (EINVAL); 1021 xpl = (struct sadb_x_policy *)request; 1022 1023 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1024 printf("%s: passed policy\n", __func__); 1025 kdebug_sadb_x_policy((struct sadb_ext *)xpl)); 1026 1027 /* Check policy type. */ 1028 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */ 1029 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 1030 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1031 return (EINVAL); 1032 1033 /* Check privileged socket. */ 1034 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1035 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0); 1036 if (error) 1037 return (EACCES); 1038 } 1039 1040 /* Allocating new SP entry. */ 1041 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1042 return (error); 1043 1044 newsp->state = IPSEC_SPSTATE_ALIVE; 1045 1046 /* Clear old SP and set new SP. */ 1047 KEY_FREESP(pcb_sp); 1048 *pcb_sp = newsp; 1049 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1050 printf("%s: new policy\n", __func__); 1051 kdebug_secpolicy(newsp)); 1052 1053 return (0); 1054 } 1055 1056 int 1057 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request, 1058 size_t len, struct ucred *cred) 1059 { 1060 INIT_VNET_IPSEC(curvnet); 1061 struct sadb_x_policy *xpl; 1062 struct secpolicy **pcb_sp; 1063 1064 /* Sanity check. */ 1065 if (inp == NULL || request == NULL) 1066 return (EINVAL); 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 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred)); 1086 } 1087 1088 int 1089 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len, 1090 struct mbuf **mp) 1091 { 1092 INIT_VNET_IPSEC(curvnet); 1093 struct sadb_x_policy *xpl; 1094 struct secpolicy *pcb_sp; 1095 1096 /* Sanity check. */ 1097 if (inp == NULL || request == NULL || mp == NULL) 1098 return (EINVAL); 1099 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 1100 if (len < sizeof(*xpl)) 1101 return (EINVAL); 1102 xpl = (struct sadb_x_policy *)request; 1103 1104 /* Select direction. */ 1105 switch (xpl->sadb_x_policy_dir) { 1106 case IPSEC_DIR_INBOUND: 1107 pcb_sp = inp->inp_sp->sp_in; 1108 break; 1109 case IPSEC_DIR_OUTBOUND: 1110 pcb_sp = inp->inp_sp->sp_out; 1111 break; 1112 default: 1113 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1114 xpl->sadb_x_policy_dir)); 1115 return (EINVAL); 1116 } 1117 1118 /* Sanity check. Should be an IPSEC_ASSERT. */ 1119 if (pcb_sp == NULL) 1120 return (EINVAL); 1121 1122 *mp = key_sp2msg(pcb_sp); 1123 if (!*mp) { 1124 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 1125 return (ENOBUFS); 1126 } 1127 1128 (*mp)->m_type = MT_DATA; 1129 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1130 printf("%s:\n", __func__); kdebug_mbuf(*mp)); 1131 1132 return (0); 1133 } 1134 1135 /* Delete policy in PCB. */ 1136 int 1137 ipsec_delete_pcbpolicy(struct inpcb *inp) 1138 { 1139 IPSEC_ASSERT(inp != NULL, ("null inp")); 1140 1141 if (inp->inp_sp == NULL) 1142 return (0); 1143 1144 if (inp->inp_sp->sp_in != NULL) 1145 KEY_FREESP(&inp->inp_sp->sp_in); 1146 1147 if (inp->inp_sp->sp_out != NULL) 1148 KEY_FREESP(&inp->inp_sp->sp_out); 1149 1150 ipsec_delpcbpolicy(inp->inp_sp); 1151 inp->inp_sp = NULL; 1152 1153 return (0); 1154 } 1155 1156 /* 1157 * Return current level. 1158 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1159 */ 1160 u_int 1161 ipsec_get_reqlevel(struct ipsecrequest *isr) 1162 { 1163 INIT_VNET_IPSEC(curvnet); 1164 u_int level = 0; 1165 u_int esp_trans_deflev, esp_net_deflev; 1166 u_int ah_trans_deflev, ah_net_deflev; 1167 1168 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument")); 1169 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1170 ("af family mismatch, src %u, dst %u", 1171 isr->sp->spidx.src.sa.sa_family, 1172 isr->sp->spidx.dst.sa.sa_family)); 1173 1174 /* XXX Note that we have ipseclog() expanded here - code sync issue. */ 1175 #define IPSEC_CHECK_DEFAULT(lev) \ 1176 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1177 && (lev) != IPSEC_LEVEL_UNIQUE) \ 1178 ? (V_ipsec_debug \ 1179 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\ 1180 (lev), IPSEC_LEVEL_REQUIRE) \ 1181 : 0), \ 1182 (lev) = IPSEC_LEVEL_REQUIRE, \ 1183 (lev) \ 1184 : (lev)) 1185 1186 /* Set default level. */ 1187 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1188 #ifdef INET 1189 case AF_INET: 1190 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev); 1191 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev); 1192 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev); 1193 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev); 1194 break; 1195 #endif 1196 #ifdef INET6 1197 case AF_INET6: 1198 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev); 1199 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev); 1200 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev); 1201 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev); 1202 break; 1203 #endif /* INET6 */ 1204 default: 1205 panic("%s: unknown af %u", 1206 __func__, isr->sp->spidx.src.sa.sa_family); 1207 } 1208 1209 #undef IPSEC_CHECK_DEFAULT 1210 1211 /* Set level. */ 1212 switch (isr->level) { 1213 case IPSEC_LEVEL_DEFAULT: 1214 switch (isr->saidx.proto) { 1215 case IPPROTO_ESP: 1216 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1217 level = esp_net_deflev; 1218 else 1219 level = esp_trans_deflev; 1220 break; 1221 case IPPROTO_AH: 1222 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1223 level = ah_net_deflev; 1224 else 1225 level = ah_trans_deflev; 1226 break; 1227 case IPPROTO_IPCOMP: 1228 /* 1229 * We don't really care, as IPcomp document says that 1230 * we shouldn't compress small packets. 1231 */ 1232 level = IPSEC_LEVEL_USE; 1233 break; 1234 default: 1235 panic("%s: Illegal protocol defined %u\n", __func__, 1236 isr->saidx.proto); 1237 } 1238 break; 1239 1240 case IPSEC_LEVEL_USE: 1241 case IPSEC_LEVEL_REQUIRE: 1242 level = isr->level; 1243 break; 1244 case IPSEC_LEVEL_UNIQUE: 1245 level = IPSEC_LEVEL_REQUIRE; 1246 break; 1247 1248 default: 1249 panic("%s: Illegal IPsec level %u\n", __func__, isr->level); 1250 } 1251 1252 return (level); 1253 } 1254 1255 /* 1256 * Check security policy requirements against the actual 1257 * packet contents. Return one if the packet should be 1258 * reject as "invalid"; otherwiser return zero to have the 1259 * packet treated as "valid". 1260 * 1261 * OUT: 1262 * 0: valid 1263 * 1: invalid 1264 */ 1265 int 1266 ipsec_in_reject(struct secpolicy *sp, struct mbuf *m) 1267 { 1268 INIT_VNET_IPSEC(curvnet); 1269 struct ipsecrequest *isr; 1270 int need_auth; 1271 1272 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1273 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1274 1275 /* Check policy. */ 1276 switch (sp->policy) { 1277 case IPSEC_POLICY_DISCARD: 1278 return (1); 1279 case IPSEC_POLICY_BYPASS: 1280 case IPSEC_POLICY_NONE: 1281 return (0); 1282 } 1283 1284 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1285 ("invalid policy %u", sp->policy)); 1286 1287 /* XXX Should compare policy against IPsec header history. */ 1288 1289 need_auth = 0; 1290 for (isr = sp->req; isr != NULL; isr = isr->next) { 1291 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1292 continue; 1293 switch (isr->saidx.proto) { 1294 case IPPROTO_ESP: 1295 if ((m->m_flags & M_DECRYPTED) == 0) { 1296 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1297 printf("%s: ESP m_flags:%x\n", __func__, 1298 m->m_flags)); 1299 return (1); 1300 } 1301 1302 if (!need_auth && 1303 isr->sav != NULL && 1304 isr->sav->tdb_authalgxform != NULL && 1305 (m->m_flags & M_AUTHIPDGM) == 0) { 1306 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1307 printf("%s: ESP/AH m_flags:%x\n", __func__, 1308 m->m_flags)); 1309 return (1); 1310 } 1311 break; 1312 case IPPROTO_AH: 1313 need_auth = 1; 1314 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1315 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1316 printf("%s: AH m_flags:%x\n", __func__, 1317 m->m_flags)); 1318 return (1); 1319 } 1320 break; 1321 case IPPROTO_IPCOMP: 1322 /* 1323 * We don't really care, as IPcomp document 1324 * says that we shouldn't compress small 1325 * packets. IPComp policy should always be 1326 * treated as being in "use" level. 1327 */ 1328 break; 1329 } 1330 } 1331 return (0); /* Valid. */ 1332 } 1333 1334 static int 1335 ipsec46_in_reject(struct mbuf *m, struct inpcb *inp) 1336 { 1337 struct secpolicy *sp; 1338 int error; 1339 int result; 1340 1341 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1342 1343 /* 1344 * Get SP for this packet. 1345 * When we are called from ip_forward(), we call 1346 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1347 */ 1348 if (inp == NULL) 1349 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1350 else 1351 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error); 1352 1353 if (sp != NULL) { 1354 result = ipsec_in_reject(sp, m); 1355 KEY_FREESP(&sp); 1356 } else { 1357 result = 0; /* XXX Should be panic? 1358 * -> No, there may be error. */ 1359 } 1360 return (result); 1361 } 1362 1363 /* 1364 * Check AH/ESP integrity. 1365 * This function is called from tcp_input(), udp_input(), 1366 * and {ah,esp}4_input for tunnel mode. 1367 */ 1368 int 1369 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1370 { 1371 INIT_VNET_IPSEC(curvnet); 1372 int result; 1373 1374 result = ipsec46_in_reject(m, inp); 1375 if (result) 1376 V_ipsec4stat.ips_in_polvio++; 1377 1378 return (result); 1379 } 1380 1381 #ifdef INET6 1382 /* 1383 * Check AH/ESP integrity. 1384 * This function is called from tcp6_input(), udp6_input(), 1385 * and {ah,esp}6_input for tunnel mode. 1386 */ 1387 int 1388 ipsec6_in_reject(struct mbuf *m, struct inpcb *inp) 1389 { 1390 INIT_VNET_IPSEC(curvnet); 1391 int result; 1392 1393 result = ipsec46_in_reject(m, inp); 1394 if (result) 1395 V_ipsec6stat.ips_in_polvio++; 1396 1397 return (result); 1398 } 1399 #endif 1400 1401 /* 1402 * Compute the byte size to be occupied by IPsec header. 1403 * In case it is tunnelled, it includes the size of outer IP header. 1404 * NOTE: SP passed is freed in this function. 1405 */ 1406 static size_t 1407 ipsec_hdrsiz_internal(struct secpolicy *sp) 1408 { 1409 INIT_VNET_IPSEC(curvnet); 1410 struct ipsecrequest *isr; 1411 size_t size; 1412 1413 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1414 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1415 1416 switch (sp->policy) { 1417 case IPSEC_POLICY_DISCARD: 1418 case IPSEC_POLICY_BYPASS: 1419 case IPSEC_POLICY_NONE: 1420 return (0); 1421 } 1422 1423 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1424 ("invalid policy %u", sp->policy)); 1425 1426 size = 0; 1427 for (isr = sp->req; isr != NULL; isr = isr->next) { 1428 size_t clen = 0; 1429 1430 switch (isr->saidx.proto) { 1431 case IPPROTO_ESP: 1432 clen = esp_hdrsiz(isr->sav); 1433 break; 1434 case IPPROTO_AH: 1435 clen = ah_hdrsiz(isr->sav); 1436 break; 1437 case IPPROTO_IPCOMP: 1438 clen = sizeof(struct ipcomp); 1439 break; 1440 } 1441 1442 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1443 switch (isr->saidx.dst.sa.sa_family) { 1444 case AF_INET: 1445 clen += sizeof(struct ip); 1446 break; 1447 #ifdef INET6 1448 case AF_INET6: 1449 clen += sizeof(struct ip6_hdr); 1450 break; 1451 #endif 1452 default: 1453 ipseclog((LOG_ERR, "%s: unknown AF %d in " 1454 "IPsec tunnel SA\n", __func__, 1455 ((struct sockaddr *)&isr->saidx.dst)->sa_family)); 1456 break; 1457 } 1458 } 1459 size += clen; 1460 } 1461 1462 return (size); 1463 } 1464 1465 /* 1466 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(), 1467 * disabled ip6_ipsec_mtu() and ip6_forward(). 1468 */ 1469 size_t 1470 ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1471 { 1472 INIT_VNET_IPSEC(curvnet); 1473 struct secpolicy *sp; 1474 int error; 1475 size_t size; 1476 1477 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1478 1479 /* Get SP for this packet. 1480 * When we are called from ip_forward(), we call 1481 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1482 */ 1483 if (inp == NULL) 1484 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1485 else 1486 sp = ipsec_getpolicybysock(m, dir, inp, &error); 1487 1488 if (sp != NULL) { 1489 size = ipsec_hdrsiz_internal(sp); 1490 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1491 printf("%s: size:%lu.\n", __func__, 1492 (unsigned long)size)); 1493 1494 KEY_FREESP(&sp); 1495 } else { 1496 size = 0; /* XXX Should be panic? 1497 * -> No, we are called w/o knowing if 1498 * IPsec processing is needed. */ 1499 } 1500 return (size); 1501 } 1502 1503 /* 1504 * Check the variable replay window. 1505 * ipsec_chkreplay() performs replay check before ICV verification. 1506 * ipsec_updatereplay() updates replay bitmap. This must be called after 1507 * ICV verification (it also performs replay check, which is usually done 1508 * beforehand). 1509 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1510 * 1511 * Based on RFC 2401. 1512 */ 1513 int 1514 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav) 1515 { 1516 const struct secreplay *replay; 1517 u_int32_t diff; 1518 int fr; 1519 u_int32_t wsizeb; /* Constant: bits of window size. */ 1520 int frlast; /* Constant: last frame. */ 1521 1522 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1523 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1524 1525 replay = sav->replay; 1526 1527 if (replay->wsize == 0) 1528 return (1); /* No need to check replay. */ 1529 1530 /* Constant. */ 1531 frlast = replay->wsize - 1; 1532 wsizeb = replay->wsize << 3; 1533 1534 /* Sequence number of 0 is invalid. */ 1535 if (seq == 0) 1536 return (0); 1537 1538 /* First time is always okay. */ 1539 if (replay->count == 0) 1540 return (1); 1541 1542 if (seq > replay->lastseq) { 1543 /* Larger sequences are okay. */ 1544 return (1); 1545 } else { 1546 /* seq is equal or less than lastseq. */ 1547 diff = replay->lastseq - seq; 1548 1549 /* Over range to check, i.e. too old or wrapped. */ 1550 if (diff >= wsizeb) 1551 return (0); 1552 1553 fr = frlast - diff / 8; 1554 1555 /* This packet already seen? */ 1556 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1557 return (0); 1558 1559 /* Out of order but good. */ 1560 return (1); 1561 } 1562 } 1563 1564 /* 1565 * Check replay counter whether to update or not. 1566 * OUT: 0: OK 1567 * 1: NG 1568 */ 1569 int 1570 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav) 1571 { 1572 INIT_VNET_IPSEC(curvnet); 1573 struct secreplay *replay; 1574 u_int32_t diff; 1575 int fr; 1576 u_int32_t wsizeb; /* Constant: bits of window size. */ 1577 int frlast; /* Constant: last frame. */ 1578 1579 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1580 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1581 1582 replay = sav->replay; 1583 1584 if (replay->wsize == 0) 1585 goto ok; /* No need to check replay. */ 1586 1587 /* Constant. */ 1588 frlast = replay->wsize - 1; 1589 wsizeb = replay->wsize << 3; 1590 1591 /* Sequence number of 0 is invalid. */ 1592 if (seq == 0) 1593 return (1); 1594 1595 /* First time. */ 1596 if (replay->count == 0) { 1597 replay->lastseq = seq; 1598 bzero(replay->bitmap, replay->wsize); 1599 (replay->bitmap)[frlast] = 1; 1600 goto ok; 1601 } 1602 1603 if (seq > replay->lastseq) { 1604 /* seq is larger than lastseq. */ 1605 diff = seq - replay->lastseq; 1606 1607 /* New larger sequence number. */ 1608 if (diff < wsizeb) { 1609 /* In window. */ 1610 /* Set bit for this packet. */ 1611 vshiftl(replay->bitmap, diff, replay->wsize); 1612 (replay->bitmap)[frlast] |= 1; 1613 } else { 1614 /* This packet has a "way larger". */ 1615 bzero(replay->bitmap, replay->wsize); 1616 (replay->bitmap)[frlast] = 1; 1617 } 1618 replay->lastseq = seq; 1619 1620 /* Larger is good. */ 1621 } else { 1622 /* seq is equal or less than lastseq. */ 1623 diff = replay->lastseq - seq; 1624 1625 /* Over range to check, i.e. too old or wrapped. */ 1626 if (diff >= wsizeb) 1627 return (1); 1628 1629 fr = frlast - diff / 8; 1630 1631 /* This packet already seen? */ 1632 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1633 return (1); 1634 1635 /* Mark as seen. */ 1636 (replay->bitmap)[fr] |= (1 << (diff % 8)); 1637 1638 /* Out of order but good. */ 1639 } 1640 1641 ok: 1642 if (replay->count == ~0) { 1643 1644 /* Set overflow flag. */ 1645 replay->overflow++; 1646 1647 /* Don't increment, no more packets accepted. */ 1648 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 1649 return (1); 1650 1651 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1652 __func__, replay->overflow, ipsec_logsastr(sav))); 1653 } 1654 1655 replay->count++; 1656 1657 return (0); 1658 } 1659 1660 /* 1661 * Shift variable length buffer to left. 1662 * IN: bitmap: pointer to the buffer 1663 * nbit: the number of to shift. 1664 * wsize: buffer size (bytes). 1665 */ 1666 static void 1667 vshiftl(unsigned char *bitmap, int nbit, int wsize) 1668 { 1669 int s, j, i; 1670 unsigned char over; 1671 1672 for (j = 0; j < nbit; j += 8) { 1673 s = (nbit - j < 8) ? (nbit - j): 8; 1674 bitmap[0] <<= s; 1675 for (i = 1; i < wsize; i++) { 1676 over = (bitmap[i] >> (8 - s)); 1677 bitmap[i] <<= s; 1678 bitmap[i-1] |= over; 1679 } 1680 } 1681 } 1682 1683 /* Return a printable string for the IPv4 address. */ 1684 static char * 1685 inet_ntoa4(struct in_addr ina) 1686 { 1687 static char buf[4][4 * sizeof "123" + 4]; 1688 unsigned char *ucp = (unsigned char *) &ina; 1689 static int i = 3; 1690 1691 /* XXX-BZ Returns static buffer. */ 1692 i = (i + 1) % 4; 1693 sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff, 1694 ucp[2] & 0xff, ucp[3] & 0xff); 1695 return (buf[i]); 1696 } 1697 1698 /* Return a printable string for the address. */ 1699 char * 1700 ipsec_address(union sockaddr_union* sa) 1701 { 1702 #ifdef INET6 1703 char ip6buf[INET6_ADDRSTRLEN]; 1704 #endif 1705 1706 switch (sa->sa.sa_family) { 1707 #ifdef INET 1708 case AF_INET: 1709 return (inet_ntoa4(sa->sin.sin_addr)); 1710 #endif /* INET */ 1711 #ifdef INET6 1712 case AF_INET6: 1713 return (ip6_sprintf(ip6buf, &sa->sin6.sin6_addr)); 1714 #endif /* INET6 */ 1715 default: 1716 return ("(unknown address family)"); 1717 } 1718 } 1719 1720 const char * 1721 ipsec_logsastr(struct secasvar *sav) 1722 { 1723 static char buf[256]; 1724 char *p; 1725 struct secasindex *saidx = &sav->sah->saidx; 1726 1727 IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 1728 ("address family mismatch")); 1729 1730 p = buf; 1731 snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi)); 1732 while (p && *p) 1733 p++; 1734 /* NB: only use ipsec_address on one address at a time. */ 1735 snprintf(p, sizeof (buf) - (p - buf), "src=%s ", 1736 ipsec_address(&saidx->src)); 1737 while (p && *p) 1738 p++; 1739 snprintf(p, sizeof (buf) - (p - buf), "dst=%s)", 1740 ipsec_address(&saidx->dst)); 1741 1742 return (buf); 1743 } 1744 1745 void 1746 ipsec_dumpmbuf(struct mbuf *m) 1747 { 1748 int totlen; 1749 int i; 1750 u_char *p; 1751 1752 totlen = 0; 1753 printf("---\n"); 1754 while (m) { 1755 p = mtod(m, u_char *); 1756 for (i = 0; i < m->m_len; i++) { 1757 printf("%02x ", p[i]); 1758 totlen++; 1759 if (totlen % 16 == 0) 1760 printf("\n"); 1761 } 1762 m = m->m_next; 1763 } 1764 if (totlen % 16 != 0) 1765 printf("\n"); 1766 printf("---\n"); 1767 } 1768 1769 static void 1770 ipsec_attach(void) 1771 { 1772 1773 #ifndef VIMAGE_GLOBALS 1774 vnet_mod_register(&vnet_ipsec_modinfo); 1775 #else 1776 ipsec_iattach(NULL); 1777 #endif 1778 1779 } 1780 1781 static int 1782 ipsec_iattach(const void *unused __unused) 1783 { 1784 INIT_VNET_IPSEC(curvnet); 1785 1786 SECPOLICY_LOCK_INIT(&V_ip4_def_policy); 1787 V_ip4_def_policy.refcnt = 1; /* NB: disallow free. */ 1788 1789 return (0); 1790 } 1791 SYSINIT(ipsec, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST, ipsec_attach, NULL); 1792 1793 1794 /* XXX This stuff doesn't belong here... */ 1795 1796 static struct xformsw* xforms = NULL; 1797 1798 /* 1799 * Register a transform; typically at system startup. 1800 */ 1801 void 1802 xform_register(struct xformsw* xsp) 1803 { 1804 1805 xsp->xf_next = xforms; 1806 xforms = xsp; 1807 } 1808 1809 /* 1810 * Initialize transform support in an sav. 1811 */ 1812 int 1813 xform_init(struct secasvar *sav, int xftype) 1814 { 1815 struct xformsw *xsp; 1816 1817 if (sav->tdb_xform != NULL) /* Previously initialized. */ 1818 return (0); 1819 for (xsp = xforms; xsp; xsp = xsp->xf_next) 1820 if (xsp->xf_type == xftype) 1821 return ((*xsp->xf_init)(sav, xsp)); 1822 return (EINVAL); 1823 } 1824