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_dependson = VNET_MOD_INET, /* XXX revisit - INET6 ? */ 252 .vmi_iattach = ipsec_iattach 253 }; 254 #endif /* !VIMAGE_GLOBALS */ 255 256 void 257 ipsec_init(void) 258 { 259 INIT_VNET_IPSEC(curvnet); 260 261 #ifdef IPSEC_DEBUG 262 V_ipsec_debug = 1; 263 #else 264 V_ipsec_debug = 0; 265 #endif 266 267 V_ip4_ah_offsetmask = 0; /* maybe IP_DF? */ 268 V_ip4_ipsec_dfbit = 0; /* DF bit on encap. 0: clear 1: set 2: copy */ 269 V_ip4_esp_trans_deflev = IPSEC_LEVEL_USE; 270 V_ip4_esp_net_deflev = IPSEC_LEVEL_USE; 271 V_ip4_ah_trans_deflev = IPSEC_LEVEL_USE; 272 V_ip4_ah_net_deflev = IPSEC_LEVEL_USE; 273 V_ip4_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 274 V_ip4_esp_randpad = -1; 275 276 V_crypto_support = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE; 277 278 #ifdef REGRESSION 279 V_ipsec_replay = 0; 280 V_ipsec_integrity = 0; 281 #endif 282 283 #ifdef INET6 284 V_ip6_esp_trans_deflev = IPSEC_LEVEL_USE; 285 V_ip6_esp_net_deflev = IPSEC_LEVEL_USE; 286 V_ip6_ah_trans_deflev = IPSEC_LEVEL_USE; 287 V_ip6_ah_net_deflev = IPSEC_LEVEL_USE; 288 V_ip6_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 289 #endif 290 } 291 292 /* 293 * Return a held reference to the default SP. 294 */ 295 static struct secpolicy * 296 key_allocsp_default(const char* where, int tag) 297 { 298 INIT_VNET_IPSEC(curvnet); 299 struct secpolicy *sp; 300 301 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 302 printf("DP key_allocsp_default from %s:%u\n", where, tag)); 303 304 sp = &V_ip4_def_policy; 305 if (sp->policy != IPSEC_POLICY_DISCARD && 306 sp->policy != IPSEC_POLICY_NONE) { 307 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n", 308 sp->policy, IPSEC_POLICY_NONE)); 309 sp->policy = IPSEC_POLICY_NONE; 310 } 311 key_addref(sp); 312 313 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 314 printf("DP key_allocsp_default returns SP:%p (%u)\n", 315 sp, sp->refcnt)); 316 return (sp); 317 } 318 #define KEY_ALLOCSP_DEFAULT() \ 319 key_allocsp_default(__FILE__, __LINE__) 320 321 /* 322 * For OUTBOUND packet having a socket. Searching SPD for packet, 323 * and return a pointer to SP. 324 * OUT: NULL: no apropreate SP found, the following value is set to error. 325 * 0 : bypass 326 * EACCES : discard packet. 327 * ENOENT : ipsec_acquire() in progress, maybe. 328 * others : error occured. 329 * others: a pointer to SP 330 * 331 * NOTE: IPv6 mapped adddress concern is implemented here. 332 */ 333 struct secpolicy * 334 ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir) 335 { 336 struct secpolicy *sp; 337 338 IPSEC_ASSERT(tdbi != NULL, ("null tdbi")); 339 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 340 ("invalid direction %u", dir)); 341 342 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir); 343 if (sp == NULL) /*XXX????*/ 344 sp = KEY_ALLOCSP_DEFAULT(); 345 IPSEC_ASSERT(sp != NULL, ("null SP")); 346 return (sp); 347 } 348 349 /* 350 * For OUTBOUND packet having a socket. Searching SPD for packet, 351 * and return a pointer to SP. 352 * OUT: NULL: no apropreate SP found, the following value is set to error. 353 * 0 : bypass 354 * EACCES : discard packet. 355 * ENOENT : ipsec_acquire() in progress, maybe. 356 * others : error occured. 357 * others: a pointer to SP 358 * 359 * NOTE: IPv6 mapped adddress concern is implemented here. 360 */ 361 static struct secpolicy * 362 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb *inp, int *error) 363 { 364 INIT_VNET_IPSEC(curvnet); 365 struct inpcbpolicy *pcbsp; 366 struct secpolicy *currsp = NULL; /* Policy on socket. */ 367 struct secpolicy *sp; 368 369 IPSEC_ASSERT(m != NULL, ("null mbuf")); 370 IPSEC_ASSERT(inp != NULL, ("null inpcb")); 371 IPSEC_ASSERT(error != NULL, ("null error")); 372 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 373 ("invalid direction %u", dir)); 374 375 /* Set spidx in pcb. */ 376 *error = ipsec_setspidx_inpcb(m, inp); 377 if (*error) 378 return (NULL); 379 380 pcbsp = inp->inp_sp; 381 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp")); 382 switch (dir) { 383 case IPSEC_DIR_INBOUND: 384 currsp = pcbsp->sp_in; 385 break; 386 case IPSEC_DIR_OUTBOUND: 387 currsp = pcbsp->sp_out; 388 break; 389 } 390 IPSEC_ASSERT(currsp != NULL, ("null currsp")); 391 392 if (pcbsp->priv) { /* When privilieged socket. */ 393 switch (currsp->policy) { 394 case IPSEC_POLICY_BYPASS: 395 case IPSEC_POLICY_IPSEC: 396 key_addref(currsp); 397 sp = currsp; 398 break; 399 400 case IPSEC_POLICY_ENTRUST: 401 /* Look for a policy in SPD. */ 402 sp = KEY_ALLOCSP(&currsp->spidx, dir); 403 if (sp == NULL) /* No SP found. */ 404 sp = KEY_ALLOCSP_DEFAULT(); 405 break; 406 407 default: 408 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n", 409 __func__, currsp->policy)); 410 *error = EINVAL; 411 return (NULL); 412 } 413 } else { /* Unpriv, SPD has policy. */ 414 sp = KEY_ALLOCSP(&currsp->spidx, dir); 415 if (sp == NULL) { /* No SP found. */ 416 switch (currsp->policy) { 417 case IPSEC_POLICY_BYPASS: 418 ipseclog((LOG_ERR, "%s: Illegal policy for " 419 "non-priviliged defined %d\n", 420 __func__, currsp->policy)); 421 *error = EINVAL; 422 return (NULL); 423 424 case IPSEC_POLICY_ENTRUST: 425 sp = KEY_ALLOCSP_DEFAULT(); 426 break; 427 428 case IPSEC_POLICY_IPSEC: 429 key_addref(currsp); 430 sp = currsp; 431 break; 432 433 default: 434 ipseclog((LOG_ERR, "%s: Invalid policy for " 435 "PCB %d\n", __func__, currsp->policy)); 436 *error = EINVAL; 437 return (NULL); 438 } 439 } 440 } 441 IPSEC_ASSERT(sp != NULL, 442 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy)); 443 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 444 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n", 445 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt)); 446 return (sp); 447 } 448 449 /* 450 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 451 * and return a pointer to SP. 452 * OUT: positive: a pointer to the entry for security policy leaf matched. 453 * NULL: no apropreate SP found, the following value is set to error. 454 * 0 : bypass 455 * EACCES : discard packet. 456 * ENOENT : ipsec_acquire() in progress, maybe. 457 * others : error occured. 458 */ 459 struct secpolicy * 460 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 461 { 462 INIT_VNET_IPSEC(curvnet); 463 struct secpolicyindex spidx; 464 struct secpolicy *sp; 465 466 IPSEC_ASSERT(m != NULL, ("null mbuf")); 467 IPSEC_ASSERT(error != NULL, ("null error")); 468 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 469 ("invalid direction %u", dir)); 470 471 sp = NULL; 472 if (key_havesp(dir)) { 473 /* Make an index to look for a policy. */ 474 *error = ipsec_setspidx(m, &spidx, 475 (flag & IP_FORWARDING) ? 0 : 1); 476 if (*error != 0) { 477 DPRINTF(("%s: setpidx failed, dir %u flag %u\n", 478 __func__, dir, flag)); 479 return (NULL); 480 } 481 spidx.dir = dir; 482 483 sp = KEY_ALLOCSP(&spidx, dir); 484 } 485 if (sp == NULL) /* No SP found, use system default. */ 486 sp = KEY_ALLOCSP_DEFAULT(); 487 IPSEC_ASSERT(sp != NULL, ("null SP")); 488 return (sp); 489 } 490 491 struct secpolicy * 492 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 493 struct inpcb *inp) 494 { 495 INIT_VNET_IPSEC(curvnet); 496 struct secpolicy *sp; 497 498 *error = 0; 499 if (inp == NULL) 500 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 501 else 502 sp = ipsec_getpolicybysock(m, dir, inp, error); 503 if (sp == NULL) { 504 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error")); 505 V_ipsec4stat.ips_out_inval++; 506 return (NULL); 507 } 508 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error)); 509 switch (sp->policy) { 510 case IPSEC_POLICY_ENTRUST: 511 default: 512 printf("%s: invalid policy %u\n", __func__, sp->policy); 513 /* FALLTHROUGH */ 514 case IPSEC_POLICY_DISCARD: 515 V_ipsec4stat.ips_out_polvio++; 516 *error = -EINVAL; /* Packet is discarded by caller. */ 517 break; 518 case IPSEC_POLICY_BYPASS: 519 case IPSEC_POLICY_NONE: 520 KEY_FREESP(&sp); 521 sp = NULL; /* NB: force NULL result. */ 522 break; 523 case IPSEC_POLICY_IPSEC: 524 if (sp->req == NULL) /* Acquire a SA. */ 525 *error = key_spdacquire(sp); 526 break; 527 } 528 if (*error != 0) { 529 KEY_FREESP(&sp); 530 sp = NULL; 531 } 532 return (sp); 533 } 534 535 static int 536 ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp) 537 { 538 int error; 539 540 IPSEC_ASSERT(inp != NULL, ("null inp")); 541 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 542 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL, 543 ("null sp_in || sp_out")); 544 545 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1); 546 if (error == 0) { 547 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 548 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx; 549 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 550 } else { 551 bzero(&inp->inp_sp->sp_in->spidx, 552 sizeof (inp->inp_sp->sp_in->spidx)); 553 bzero(&inp->inp_sp->sp_out->spidx, 554 sizeof (inp->inp_sp->sp_in->spidx)); 555 } 556 return (error); 557 } 558 559 /* 560 * Configure security policy index (src/dst/proto/sport/dport) 561 * by looking at the content of mbuf. 562 * The caller is responsible for error recovery (like clearing up spidx). 563 */ 564 static int 565 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 566 { 567 INIT_VNET_IPSEC(curvnet); 568 struct ip *ip = NULL; 569 struct ip ipbuf; 570 u_int v; 571 struct mbuf *n; 572 int len; 573 int error; 574 575 IPSEC_ASSERT(m != NULL, ("null mbuf")); 576 577 /* 578 * Validate m->m_pkthdr.len. We see incorrect length if we 579 * mistakenly call this function with inconsistent mbuf chain 580 * (like 4.4BSD tcp/udp processing). XXX Should we panic here? 581 */ 582 len = 0; 583 for (n = m; n; n = n->m_next) 584 len += n->m_len; 585 if (m->m_pkthdr.len != len) { 586 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 587 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n", 588 __func__, len, m->m_pkthdr.len)); 589 return (EINVAL); 590 } 591 592 if (m->m_pkthdr.len < sizeof(struct ip)) { 593 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 594 printf("%s: pkthdr len(%d) too small (v4), ignored.\n", 595 __func__, m->m_pkthdr.len)); 596 return (EINVAL); 597 } 598 599 if (m->m_len >= sizeof(*ip)) 600 ip = mtod(m, struct ip *); 601 else { 602 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf); 603 ip = &ipbuf; 604 } 605 #ifdef _IP_VHL 606 v = _IP_VHL_V(ip->ip_vhl); 607 #else 608 v = ip->ip_v; 609 #endif 610 switch (v) { 611 case 4: 612 error = ipsec4_setspidx_ipaddr(m, spidx); 613 if (error) 614 return (error); 615 ipsec4_get_ulp(m, spidx, needport); 616 return (0); 617 #ifdef INET6 618 case 6: 619 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 620 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 621 printf("%s: pkthdr len(%d) too small (v6), " 622 "ignored\n", __func__, m->m_pkthdr.len)); 623 return (EINVAL); 624 } 625 error = ipsec6_setspidx_ipaddr(m, spidx); 626 if (error) 627 return (error); 628 ipsec6_get_ulp(m, spidx, needport); 629 return (0); 630 #endif 631 default: 632 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 633 printf("%s: " "unknown IP version %u, ignored.\n", 634 __func__, v)); 635 return (EINVAL); 636 } 637 } 638 639 static void 640 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 641 { 642 u_int8_t nxt; 643 int off; 644 645 /* Sanity check. */ 646 IPSEC_ASSERT(m != NULL, ("null mbuf")); 647 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short")); 648 649 /* NB: ip_input() flips it into host endian. XXX Need more checking. */ 650 if (m->m_len < sizeof (struct ip)) { 651 struct ip *ip = mtod(m, struct ip *); 652 if (ip->ip_off & (IP_MF | IP_OFFMASK)) 653 goto done; 654 #ifdef _IP_VHL 655 off = _IP_VHL_HL(ip->ip_vhl) << 2; 656 #else 657 off = ip->ip_hl << 2; 658 #endif 659 nxt = ip->ip_p; 660 } else { 661 struct ip ih; 662 663 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih); 664 if (ih.ip_off & (IP_MF | IP_OFFMASK)) 665 goto done; 666 #ifdef _IP_VHL 667 off = _IP_VHL_HL(ih.ip_vhl) << 2; 668 #else 669 off = ih.ip_hl << 2; 670 #endif 671 nxt = ih.ip_p; 672 } 673 674 while (off < m->m_pkthdr.len) { 675 struct ip6_ext ip6e; 676 struct tcphdr th; 677 struct udphdr uh; 678 679 switch (nxt) { 680 case IPPROTO_TCP: 681 spidx->ul_proto = nxt; 682 if (!needport) 683 goto done_proto; 684 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 685 goto done; 686 m_copydata(m, off, sizeof (th), (caddr_t) &th); 687 spidx->src.sin.sin_port = th.th_sport; 688 spidx->dst.sin.sin_port = th.th_dport; 689 return; 690 case IPPROTO_UDP: 691 spidx->ul_proto = nxt; 692 if (!needport) 693 goto done_proto; 694 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 695 goto done; 696 m_copydata(m, off, sizeof (uh), (caddr_t) &uh); 697 spidx->src.sin.sin_port = uh.uh_sport; 698 spidx->dst.sin.sin_port = uh.uh_dport; 699 return; 700 case IPPROTO_AH: 701 if (off + sizeof(ip6e) > m->m_pkthdr.len) 702 goto done; 703 /* XXX Sigh, this works but is totally bogus. */ 704 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e); 705 off += (ip6e.ip6e_len + 2) << 2; 706 nxt = ip6e.ip6e_nxt; 707 break; 708 case IPPROTO_ICMP: 709 default: 710 /* XXX Intermediate headers??? */ 711 spidx->ul_proto = nxt; 712 goto done_proto; 713 } 714 } 715 done: 716 spidx->ul_proto = IPSEC_ULPROTO_ANY; 717 done_proto: 718 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 719 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 720 } 721 722 /* Assumes that m is sane. */ 723 static int 724 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 725 { 726 static const struct sockaddr_in template = { 727 sizeof (struct sockaddr_in), 728 AF_INET, 729 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 730 }; 731 732 spidx->src.sin = template; 733 spidx->dst.sin = template; 734 735 if (m->m_len < sizeof (struct ip)) { 736 m_copydata(m, offsetof(struct ip, ip_src), 737 sizeof (struct in_addr), 738 (caddr_t) &spidx->src.sin.sin_addr); 739 m_copydata(m, offsetof(struct ip, ip_dst), 740 sizeof (struct in_addr), 741 (caddr_t) &spidx->dst.sin.sin_addr); 742 } else { 743 struct ip *ip = mtod(m, struct ip *); 744 spidx->src.sin.sin_addr = ip->ip_src; 745 spidx->dst.sin.sin_addr = ip->ip_dst; 746 } 747 748 spidx->prefs = sizeof(struct in_addr) << 3; 749 spidx->prefd = sizeof(struct in_addr) << 3; 750 751 return (0); 752 } 753 754 #ifdef INET6 755 static void 756 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 757 { 758 INIT_VNET_IPSEC(curvnet); 759 int off, nxt; 760 struct tcphdr th; 761 struct udphdr uh; 762 struct icmp6_hdr ih; 763 764 /* Sanity check. */ 765 if (m == NULL) 766 panic("%s: NULL pointer was passed.\n", __func__); 767 768 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 769 printf("%s:\n", __func__); kdebug_mbuf(m)); 770 771 /* Set default. */ 772 spidx->ul_proto = IPSEC_ULPROTO_ANY; 773 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 774 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 775 776 nxt = -1; 777 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 778 if (off < 0 || m->m_pkthdr.len < off) 779 return; 780 781 switch (nxt) { 782 case IPPROTO_TCP: 783 spidx->ul_proto = nxt; 784 if (!needport) 785 break; 786 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 787 break; 788 m_copydata(m, off, sizeof(th), (caddr_t)&th); 789 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 790 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 791 break; 792 case IPPROTO_UDP: 793 spidx->ul_proto = nxt; 794 if (!needport) 795 break; 796 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 797 break; 798 m_copydata(m, off, sizeof(uh), (caddr_t)&uh); 799 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 800 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 801 break; 802 case IPPROTO_ICMPV6: 803 spidx->ul_proto = nxt; 804 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 805 break; 806 m_copydata(m, off, sizeof(ih), (caddr_t)&ih); 807 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 808 htons((uint16_t)ih.icmp6_type); 809 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 810 htons((uint16_t)ih.icmp6_code); 811 break; 812 default: 813 /* XXX Intermediate headers??? */ 814 spidx->ul_proto = nxt; 815 break; 816 } 817 } 818 819 /* Assumes that m is sane. */ 820 static int 821 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 822 { 823 struct ip6_hdr *ip6 = NULL; 824 struct ip6_hdr ip6buf; 825 struct sockaddr_in6 *sin6; 826 827 if (m->m_len >= sizeof(*ip6)) 828 ip6 = mtod(m, struct ip6_hdr *); 829 else { 830 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf); 831 ip6 = &ip6buf; 832 } 833 834 sin6 = (struct sockaddr_in6 *)&spidx->src; 835 bzero(sin6, sizeof(*sin6)); 836 sin6->sin6_family = AF_INET6; 837 sin6->sin6_len = sizeof(struct sockaddr_in6); 838 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src)); 839 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 840 sin6->sin6_addr.s6_addr16[1] = 0; 841 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 842 } 843 spidx->prefs = sizeof(struct in6_addr) << 3; 844 845 sin6 = (struct sockaddr_in6 *)&spidx->dst; 846 bzero(sin6, sizeof(*sin6)); 847 sin6->sin6_family = AF_INET6; 848 sin6->sin6_len = sizeof(struct sockaddr_in6); 849 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst)); 850 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 851 sin6->sin6_addr.s6_addr16[1] = 0; 852 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 853 } 854 spidx->prefd = sizeof(struct in6_addr) << 3; 855 856 return (0); 857 } 858 #endif 859 860 static void 861 ipsec_delpcbpolicy(struct inpcbpolicy *p) 862 { 863 864 free(p, M_IPSEC_INPCB); 865 } 866 867 /* Initialize policy in PCB. */ 868 int 869 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp) 870 { 871 INIT_VNET_IPSEC(curvnet); 872 struct inpcbpolicy *new; 873 874 /* Sanity check. */ 875 if (so == NULL || pcb_sp == NULL) 876 panic("%s: NULL pointer was passed.\n", __func__); 877 878 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy), 879 M_IPSEC_INPCB, M_NOWAIT|M_ZERO); 880 if (new == NULL) { 881 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 882 return (ENOBUFS); 883 } 884 885 new->priv = IPSEC_IS_PRIVILEGED_SO(so); 886 887 if ((new->sp_in = KEY_NEWSP()) == NULL) { 888 ipsec_delpcbpolicy(new); 889 return (ENOBUFS); 890 } 891 new->sp_in->state = IPSEC_SPSTATE_ALIVE; 892 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 893 894 if ((new->sp_out = KEY_NEWSP()) == NULL) { 895 KEY_FREESP(&new->sp_in); 896 ipsec_delpcbpolicy(new); 897 return (ENOBUFS); 898 } 899 new->sp_out->state = IPSEC_SPSTATE_ALIVE; 900 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 901 902 *pcb_sp = new; 903 904 return (0); 905 } 906 907 /* Copy old IPsec policy into new. */ 908 int 909 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new) 910 { 911 struct secpolicy *sp; 912 913 sp = ipsec_deepcopy_policy(old->sp_in); 914 if (sp) { 915 KEY_FREESP(&new->sp_in); 916 new->sp_in = sp; 917 } else 918 return (ENOBUFS); 919 920 sp = ipsec_deepcopy_policy(old->sp_out); 921 if (sp) { 922 KEY_FREESP(&new->sp_out); 923 new->sp_out = sp; 924 } else 925 return (ENOBUFS); 926 927 new->priv = old->priv; 928 929 return (0); 930 } 931 932 struct ipsecrequest * 933 ipsec_newisr(void) 934 { 935 struct ipsecrequest *p; 936 937 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO); 938 if (p != NULL) 939 IPSECREQUEST_LOCK_INIT(p); 940 return (p); 941 } 942 943 void 944 ipsec_delisr(struct ipsecrequest *p) 945 { 946 947 IPSECREQUEST_LOCK_DESTROY(p); 948 free(p, M_IPSEC_SR); 949 } 950 951 /* Deep-copy a policy in PCB. */ 952 static struct secpolicy * 953 ipsec_deepcopy_policy(struct secpolicy *src) 954 { 955 struct ipsecrequest *newchain = NULL; 956 struct ipsecrequest *p; 957 struct ipsecrequest **q; 958 struct ipsecrequest *r; 959 struct secpolicy *dst; 960 961 if (src == NULL) 962 return (NULL); 963 dst = KEY_NEWSP(); 964 if (dst == NULL) 965 return (NULL); 966 967 /* 968 * Deep-copy IPsec request chain. This is required since struct 969 * ipsecrequest is not reference counted. 970 */ 971 q = &newchain; 972 for (p = src->req; p; p = p->next) { 973 *q = ipsec_newisr(); 974 if (*q == NULL) 975 goto fail; 976 (*q)->saidx.proto = p->saidx.proto; 977 (*q)->saidx.mode = p->saidx.mode; 978 (*q)->level = p->level; 979 (*q)->saidx.reqid = p->saidx.reqid; 980 981 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src)); 982 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst)); 983 984 (*q)->sp = dst; 985 986 q = &((*q)->next); 987 } 988 989 dst->req = newchain; 990 dst->state = src->state; 991 dst->policy = src->policy; 992 /* Do not touch the refcnt fields. */ 993 994 return (dst); 995 996 fail: 997 for (p = newchain; p; p = r) { 998 r = p->next; 999 ipsec_delisr(p); 1000 p = NULL; 1001 } 1002 return (NULL); 1003 } 1004 1005 /* Set policy and IPsec request if present. */ 1006 static int 1007 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname, 1008 caddr_t request, size_t len, struct ucred *cred) 1009 { 1010 INIT_VNET_IPSEC(curvnet); 1011 struct sadb_x_policy *xpl; 1012 struct secpolicy *newsp = NULL; 1013 int error; 1014 1015 /* Sanity check. */ 1016 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL) 1017 return (EINVAL); 1018 if (len < sizeof(*xpl)) 1019 return (EINVAL); 1020 xpl = (struct sadb_x_policy *)request; 1021 1022 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1023 printf("%s: passed policy\n", __func__); 1024 kdebug_sadb_x_policy((struct sadb_ext *)xpl)); 1025 1026 /* Check policy type. */ 1027 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */ 1028 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 1029 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1030 return (EINVAL); 1031 1032 /* Check privileged socket. */ 1033 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1034 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0); 1035 if (error) 1036 return (EACCES); 1037 } 1038 1039 /* Allocating new SP entry. */ 1040 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1041 return (error); 1042 1043 newsp->state = IPSEC_SPSTATE_ALIVE; 1044 1045 /* Clear old SP and set new SP. */ 1046 KEY_FREESP(pcb_sp); 1047 *pcb_sp = newsp; 1048 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1049 printf("%s: new policy\n", __func__); 1050 kdebug_secpolicy(newsp)); 1051 1052 return (0); 1053 } 1054 1055 int 1056 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request, 1057 size_t len, struct ucred *cred) 1058 { 1059 INIT_VNET_IPSEC(curvnet); 1060 struct sadb_x_policy *xpl; 1061 struct secpolicy **pcb_sp; 1062 1063 /* Sanity check. */ 1064 if (inp == NULL || request == NULL) 1065 return (EINVAL); 1066 if (len < sizeof(*xpl)) 1067 return (EINVAL); 1068 xpl = (struct sadb_x_policy *)request; 1069 1070 /* Select direction. */ 1071 switch (xpl->sadb_x_policy_dir) { 1072 case IPSEC_DIR_INBOUND: 1073 pcb_sp = &inp->inp_sp->sp_in; 1074 break; 1075 case IPSEC_DIR_OUTBOUND: 1076 pcb_sp = &inp->inp_sp->sp_out; 1077 break; 1078 default: 1079 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1080 xpl->sadb_x_policy_dir)); 1081 return (EINVAL); 1082 } 1083 1084 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred)); 1085 } 1086 1087 int 1088 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len, 1089 struct mbuf **mp) 1090 { 1091 INIT_VNET_IPSEC(curvnet); 1092 struct sadb_x_policy *xpl; 1093 struct secpolicy *pcb_sp; 1094 1095 /* Sanity check. */ 1096 if (inp == NULL || request == NULL || mp == NULL) 1097 return (EINVAL); 1098 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 1099 if (len < sizeof(*xpl)) 1100 return (EINVAL); 1101 xpl = (struct sadb_x_policy *)request; 1102 1103 /* Select direction. */ 1104 switch (xpl->sadb_x_policy_dir) { 1105 case IPSEC_DIR_INBOUND: 1106 pcb_sp = inp->inp_sp->sp_in; 1107 break; 1108 case IPSEC_DIR_OUTBOUND: 1109 pcb_sp = inp->inp_sp->sp_out; 1110 break; 1111 default: 1112 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1113 xpl->sadb_x_policy_dir)); 1114 return (EINVAL); 1115 } 1116 1117 /* Sanity check. Should be an IPSEC_ASSERT. */ 1118 if (pcb_sp == NULL) 1119 return (EINVAL); 1120 1121 *mp = key_sp2msg(pcb_sp); 1122 if (!*mp) { 1123 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 1124 return (ENOBUFS); 1125 } 1126 1127 (*mp)->m_type = MT_DATA; 1128 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1129 printf("%s:\n", __func__); kdebug_mbuf(*mp)); 1130 1131 return (0); 1132 } 1133 1134 /* Delete policy in PCB. */ 1135 int 1136 ipsec_delete_pcbpolicy(struct inpcb *inp) 1137 { 1138 IPSEC_ASSERT(inp != NULL, ("null inp")); 1139 1140 if (inp->inp_sp == NULL) 1141 return (0); 1142 1143 if (inp->inp_sp->sp_in != NULL) 1144 KEY_FREESP(&inp->inp_sp->sp_in); 1145 1146 if (inp->inp_sp->sp_out != NULL) 1147 KEY_FREESP(&inp->inp_sp->sp_out); 1148 1149 ipsec_delpcbpolicy(inp->inp_sp); 1150 inp->inp_sp = NULL; 1151 1152 return (0); 1153 } 1154 1155 /* 1156 * Return current level. 1157 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1158 */ 1159 u_int 1160 ipsec_get_reqlevel(struct ipsecrequest *isr) 1161 { 1162 INIT_VNET_IPSEC(curvnet); 1163 u_int level = 0; 1164 u_int esp_trans_deflev, esp_net_deflev; 1165 u_int ah_trans_deflev, ah_net_deflev; 1166 1167 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument")); 1168 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1169 ("af family mismatch, src %u, dst %u", 1170 isr->sp->spidx.src.sa.sa_family, 1171 isr->sp->spidx.dst.sa.sa_family)); 1172 1173 /* XXX Note that we have ipseclog() expanded here - code sync issue. */ 1174 #define IPSEC_CHECK_DEFAULT(lev) \ 1175 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1176 && (lev) != IPSEC_LEVEL_UNIQUE) \ 1177 ? (V_ipsec_debug \ 1178 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\ 1179 (lev), IPSEC_LEVEL_REQUIRE) \ 1180 : 0), \ 1181 (lev) = IPSEC_LEVEL_REQUIRE, \ 1182 (lev) \ 1183 : (lev)) 1184 1185 /* Set default level. */ 1186 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1187 #ifdef INET 1188 case AF_INET: 1189 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev); 1190 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev); 1191 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev); 1192 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev); 1193 break; 1194 #endif 1195 #ifdef INET6 1196 case AF_INET6: 1197 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev); 1198 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev); 1199 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev); 1200 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev); 1201 break; 1202 #endif /* INET6 */ 1203 default: 1204 panic("%s: unknown af %u", 1205 __func__, isr->sp->spidx.src.sa.sa_family); 1206 } 1207 1208 #undef IPSEC_CHECK_DEFAULT 1209 1210 /* Set level. */ 1211 switch (isr->level) { 1212 case IPSEC_LEVEL_DEFAULT: 1213 switch (isr->saidx.proto) { 1214 case IPPROTO_ESP: 1215 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1216 level = esp_net_deflev; 1217 else 1218 level = esp_trans_deflev; 1219 break; 1220 case IPPROTO_AH: 1221 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1222 level = ah_net_deflev; 1223 else 1224 level = ah_trans_deflev; 1225 break; 1226 case IPPROTO_IPCOMP: 1227 /* 1228 * We don't really care, as IPcomp document says that 1229 * we shouldn't compress small packets. 1230 */ 1231 level = IPSEC_LEVEL_USE; 1232 break; 1233 default: 1234 panic("%s: Illegal protocol defined %u\n", __func__, 1235 isr->saidx.proto); 1236 } 1237 break; 1238 1239 case IPSEC_LEVEL_USE: 1240 case IPSEC_LEVEL_REQUIRE: 1241 level = isr->level; 1242 break; 1243 case IPSEC_LEVEL_UNIQUE: 1244 level = IPSEC_LEVEL_REQUIRE; 1245 break; 1246 1247 default: 1248 panic("%s: Illegal IPsec level %u\n", __func__, isr->level); 1249 } 1250 1251 return (level); 1252 } 1253 1254 /* 1255 * Check security policy requirements against the actual 1256 * packet contents. Return one if the packet should be 1257 * reject as "invalid"; otherwiser return zero to have the 1258 * packet treated as "valid". 1259 * 1260 * OUT: 1261 * 0: valid 1262 * 1: invalid 1263 */ 1264 int 1265 ipsec_in_reject(struct secpolicy *sp, struct mbuf *m) 1266 { 1267 INIT_VNET_IPSEC(curvnet); 1268 struct ipsecrequest *isr; 1269 int need_auth; 1270 1271 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1272 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1273 1274 /* Check policy. */ 1275 switch (sp->policy) { 1276 case IPSEC_POLICY_DISCARD: 1277 return (1); 1278 case IPSEC_POLICY_BYPASS: 1279 case IPSEC_POLICY_NONE: 1280 return (0); 1281 } 1282 1283 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1284 ("invalid policy %u", sp->policy)); 1285 1286 /* XXX Should compare policy against IPsec header history. */ 1287 1288 need_auth = 0; 1289 for (isr = sp->req; isr != NULL; isr = isr->next) { 1290 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1291 continue; 1292 switch (isr->saidx.proto) { 1293 case IPPROTO_ESP: 1294 if ((m->m_flags & M_DECRYPTED) == 0) { 1295 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1296 printf("%s: ESP m_flags:%x\n", __func__, 1297 m->m_flags)); 1298 return (1); 1299 } 1300 1301 if (!need_auth && 1302 isr->sav != NULL && 1303 isr->sav->tdb_authalgxform != NULL && 1304 (m->m_flags & M_AUTHIPDGM) == 0) { 1305 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1306 printf("%s: ESP/AH m_flags:%x\n", __func__, 1307 m->m_flags)); 1308 return (1); 1309 } 1310 break; 1311 case IPPROTO_AH: 1312 need_auth = 1; 1313 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1314 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1315 printf("%s: AH m_flags:%x\n", __func__, 1316 m->m_flags)); 1317 return (1); 1318 } 1319 break; 1320 case IPPROTO_IPCOMP: 1321 /* 1322 * We don't really care, as IPcomp document 1323 * says that we shouldn't compress small 1324 * packets. IPComp policy should always be 1325 * treated as being in "use" level. 1326 */ 1327 break; 1328 } 1329 } 1330 return (0); /* Valid. */ 1331 } 1332 1333 static int 1334 ipsec46_in_reject(struct mbuf *m, struct inpcb *inp) 1335 { 1336 struct secpolicy *sp; 1337 int error; 1338 int result; 1339 1340 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1341 1342 /* 1343 * Get SP for this packet. 1344 * When we are called from ip_forward(), we call 1345 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1346 */ 1347 if (inp == NULL) 1348 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1349 else 1350 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error); 1351 1352 if (sp != NULL) { 1353 result = ipsec_in_reject(sp, m); 1354 KEY_FREESP(&sp); 1355 } else { 1356 result = 0; /* XXX Should be panic? 1357 * -> No, there may be error. */ 1358 } 1359 return (result); 1360 } 1361 1362 /* 1363 * Check AH/ESP integrity. 1364 * This function is called from tcp_input(), udp_input(), 1365 * and {ah,esp}4_input for tunnel mode. 1366 */ 1367 int 1368 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1369 { 1370 INIT_VNET_IPSEC(curvnet); 1371 int result; 1372 1373 result = ipsec46_in_reject(m, inp); 1374 if (result) 1375 V_ipsec4stat.ips_in_polvio++; 1376 1377 return (result); 1378 } 1379 1380 #ifdef INET6 1381 /* 1382 * Check AH/ESP integrity. 1383 * This function is called from tcp6_input(), udp6_input(), 1384 * and {ah,esp}6_input for tunnel mode. 1385 */ 1386 int 1387 ipsec6_in_reject(struct mbuf *m, struct inpcb *inp) 1388 { 1389 INIT_VNET_IPSEC(curvnet); 1390 int result; 1391 1392 result = ipsec46_in_reject(m, inp); 1393 if (result) 1394 V_ipsec6stat.ips_in_polvio++; 1395 1396 return (result); 1397 } 1398 #endif 1399 1400 /* 1401 * Compute the byte size to be occupied by IPsec header. 1402 * In case it is tunnelled, it includes the size of outer IP header. 1403 * NOTE: SP passed is freed in this function. 1404 */ 1405 static size_t 1406 ipsec_hdrsiz_internal(struct secpolicy *sp) 1407 { 1408 INIT_VNET_IPSEC(curvnet); 1409 struct ipsecrequest *isr; 1410 size_t size; 1411 1412 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1413 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1414 1415 switch (sp->policy) { 1416 case IPSEC_POLICY_DISCARD: 1417 case IPSEC_POLICY_BYPASS: 1418 case IPSEC_POLICY_NONE: 1419 return (0); 1420 } 1421 1422 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1423 ("invalid policy %u", sp->policy)); 1424 1425 size = 0; 1426 for (isr = sp->req; isr != NULL; isr = isr->next) { 1427 size_t clen = 0; 1428 1429 switch (isr->saidx.proto) { 1430 case IPPROTO_ESP: 1431 clen = esp_hdrsiz(isr->sav); 1432 break; 1433 case IPPROTO_AH: 1434 clen = ah_hdrsiz(isr->sav); 1435 break; 1436 case IPPROTO_IPCOMP: 1437 clen = sizeof(struct ipcomp); 1438 break; 1439 } 1440 1441 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1442 switch (isr->saidx.dst.sa.sa_family) { 1443 case AF_INET: 1444 clen += sizeof(struct ip); 1445 break; 1446 #ifdef INET6 1447 case AF_INET6: 1448 clen += sizeof(struct ip6_hdr); 1449 break; 1450 #endif 1451 default: 1452 ipseclog((LOG_ERR, "%s: unknown AF %d in " 1453 "IPsec tunnel SA\n", __func__, 1454 ((struct sockaddr *)&isr->saidx.dst)->sa_family)); 1455 break; 1456 } 1457 } 1458 size += clen; 1459 } 1460 1461 return (size); 1462 } 1463 1464 /* 1465 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(), 1466 * disabled ip6_ipsec_mtu() and ip6_forward(). 1467 */ 1468 size_t 1469 ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1470 { 1471 INIT_VNET_IPSEC(curvnet); 1472 struct secpolicy *sp; 1473 int error; 1474 size_t size; 1475 1476 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1477 1478 /* Get SP for this packet. 1479 * When we are called from ip_forward(), we call 1480 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1481 */ 1482 if (inp == NULL) 1483 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1484 else 1485 sp = ipsec_getpolicybysock(m, dir, inp, &error); 1486 1487 if (sp != NULL) { 1488 size = ipsec_hdrsiz_internal(sp); 1489 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1490 printf("%s: size:%lu.\n", __func__, 1491 (unsigned long)size)); 1492 1493 KEY_FREESP(&sp); 1494 } else { 1495 size = 0; /* XXX Should be panic? 1496 * -> No, we are called w/o knowing if 1497 * IPsec processing is needed. */ 1498 } 1499 return (size); 1500 } 1501 1502 /* 1503 * Check the variable replay window. 1504 * ipsec_chkreplay() performs replay check before ICV verification. 1505 * ipsec_updatereplay() updates replay bitmap. This must be called after 1506 * ICV verification (it also performs replay check, which is usually done 1507 * beforehand). 1508 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1509 * 1510 * Based on RFC 2401. 1511 */ 1512 int 1513 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav) 1514 { 1515 const struct secreplay *replay; 1516 u_int32_t diff; 1517 int fr; 1518 u_int32_t wsizeb; /* Constant: bits of window size. */ 1519 int frlast; /* Constant: last frame. */ 1520 1521 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1522 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1523 1524 replay = sav->replay; 1525 1526 if (replay->wsize == 0) 1527 return (1); /* No need to check replay. */ 1528 1529 /* Constant. */ 1530 frlast = replay->wsize - 1; 1531 wsizeb = replay->wsize << 3; 1532 1533 /* Sequence number of 0 is invalid. */ 1534 if (seq == 0) 1535 return (0); 1536 1537 /* First time is always okay. */ 1538 if (replay->count == 0) 1539 return (1); 1540 1541 if (seq > replay->lastseq) { 1542 /* Larger sequences are okay. */ 1543 return (1); 1544 } else { 1545 /* seq is equal or less than lastseq. */ 1546 diff = replay->lastseq - seq; 1547 1548 /* Over range to check, i.e. too old or wrapped. */ 1549 if (diff >= wsizeb) 1550 return (0); 1551 1552 fr = frlast - diff / 8; 1553 1554 /* This packet already seen? */ 1555 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1556 return (0); 1557 1558 /* Out of order but good. */ 1559 return (1); 1560 } 1561 } 1562 1563 /* 1564 * Check replay counter whether to update or not. 1565 * OUT: 0: OK 1566 * 1: NG 1567 */ 1568 int 1569 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav) 1570 { 1571 INIT_VNET_IPSEC(curvnet); 1572 struct secreplay *replay; 1573 u_int32_t diff; 1574 int fr; 1575 u_int32_t wsizeb; /* Constant: bits of window size. */ 1576 int frlast; /* Constant: last frame. */ 1577 1578 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1579 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1580 1581 replay = sav->replay; 1582 1583 if (replay->wsize == 0) 1584 goto ok; /* No need to check replay. */ 1585 1586 /* Constant. */ 1587 frlast = replay->wsize - 1; 1588 wsizeb = replay->wsize << 3; 1589 1590 /* Sequence number of 0 is invalid. */ 1591 if (seq == 0) 1592 return (1); 1593 1594 /* First time. */ 1595 if (replay->count == 0) { 1596 replay->lastseq = seq; 1597 bzero(replay->bitmap, replay->wsize); 1598 (replay->bitmap)[frlast] = 1; 1599 goto ok; 1600 } 1601 1602 if (seq > replay->lastseq) { 1603 /* seq is larger than lastseq. */ 1604 diff = seq - replay->lastseq; 1605 1606 /* New larger sequence number. */ 1607 if (diff < wsizeb) { 1608 /* In window. */ 1609 /* Set bit for this packet. */ 1610 vshiftl(replay->bitmap, diff, replay->wsize); 1611 (replay->bitmap)[frlast] |= 1; 1612 } else { 1613 /* This packet has a "way larger". */ 1614 bzero(replay->bitmap, replay->wsize); 1615 (replay->bitmap)[frlast] = 1; 1616 } 1617 replay->lastseq = seq; 1618 1619 /* Larger is good. */ 1620 } else { 1621 /* seq is equal or less than lastseq. */ 1622 diff = replay->lastseq - seq; 1623 1624 /* Over range to check, i.e. too old or wrapped. */ 1625 if (diff >= wsizeb) 1626 return (1); 1627 1628 fr = frlast - diff / 8; 1629 1630 /* This packet already seen? */ 1631 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1632 return (1); 1633 1634 /* Mark as seen. */ 1635 (replay->bitmap)[fr] |= (1 << (diff % 8)); 1636 1637 /* Out of order but good. */ 1638 } 1639 1640 ok: 1641 if (replay->count == ~0) { 1642 1643 /* Set overflow flag. */ 1644 replay->overflow++; 1645 1646 /* Don't increment, no more packets accepted. */ 1647 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 1648 return (1); 1649 1650 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1651 __func__, replay->overflow, ipsec_logsastr(sav))); 1652 } 1653 1654 replay->count++; 1655 1656 return (0); 1657 } 1658 1659 /* 1660 * Shift variable length buffer to left. 1661 * IN: bitmap: pointer to the buffer 1662 * nbit: the number of to shift. 1663 * wsize: buffer size (bytes). 1664 */ 1665 static void 1666 vshiftl(unsigned char *bitmap, int nbit, int wsize) 1667 { 1668 int s, j, i; 1669 unsigned char over; 1670 1671 for (j = 0; j < nbit; j += 8) { 1672 s = (nbit - j < 8) ? (nbit - j): 8; 1673 bitmap[0] <<= s; 1674 for (i = 1; i < wsize; i++) { 1675 over = (bitmap[i] >> (8 - s)); 1676 bitmap[i] <<= s; 1677 bitmap[i-1] |= over; 1678 } 1679 } 1680 } 1681 1682 /* Return a printable string for the IPv4 address. */ 1683 static char * 1684 inet_ntoa4(struct in_addr ina) 1685 { 1686 static char buf[4][4 * sizeof "123" + 4]; 1687 unsigned char *ucp = (unsigned char *) &ina; 1688 static int i = 3; 1689 1690 /* XXX-BZ Returns static buffer. */ 1691 i = (i + 1) % 4; 1692 sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff, 1693 ucp[2] & 0xff, ucp[3] & 0xff); 1694 return (buf[i]); 1695 } 1696 1697 /* Return a printable string for the address. */ 1698 char * 1699 ipsec_address(union sockaddr_union* sa) 1700 { 1701 #ifdef INET6 1702 char ip6buf[INET6_ADDRSTRLEN]; 1703 #endif 1704 1705 switch (sa->sa.sa_family) { 1706 #ifdef INET 1707 case AF_INET: 1708 return (inet_ntoa4(sa->sin.sin_addr)); 1709 #endif /* INET */ 1710 #ifdef INET6 1711 case AF_INET6: 1712 return (ip6_sprintf(ip6buf, &sa->sin6.sin6_addr)); 1713 #endif /* INET6 */ 1714 default: 1715 return ("(unknown address family)"); 1716 } 1717 } 1718 1719 const char * 1720 ipsec_logsastr(struct secasvar *sav) 1721 { 1722 static char buf[256]; 1723 char *p; 1724 struct secasindex *saidx = &sav->sah->saidx; 1725 1726 IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 1727 ("address family mismatch")); 1728 1729 p = buf; 1730 snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi)); 1731 while (p && *p) 1732 p++; 1733 /* NB: only use ipsec_address on one address at a time. */ 1734 snprintf(p, sizeof (buf) - (p - buf), "src=%s ", 1735 ipsec_address(&saidx->src)); 1736 while (p && *p) 1737 p++; 1738 snprintf(p, sizeof (buf) - (p - buf), "dst=%s)", 1739 ipsec_address(&saidx->dst)); 1740 1741 return (buf); 1742 } 1743 1744 void 1745 ipsec_dumpmbuf(struct mbuf *m) 1746 { 1747 int totlen; 1748 int i; 1749 u_char *p; 1750 1751 totlen = 0; 1752 printf("---\n"); 1753 while (m) { 1754 p = mtod(m, u_char *); 1755 for (i = 0; i < m->m_len; i++) { 1756 printf("%02x ", p[i]); 1757 totlen++; 1758 if (totlen % 16 == 0) 1759 printf("\n"); 1760 } 1761 m = m->m_next; 1762 } 1763 if (totlen % 16 != 0) 1764 printf("\n"); 1765 printf("---\n"); 1766 } 1767 1768 static void 1769 ipsec_attach(void) 1770 { 1771 1772 #ifndef VIMAGE_GLOBALS 1773 vnet_mod_register(&vnet_ipsec_modinfo); 1774 #else 1775 ipsec_iattach(NULL); 1776 #endif 1777 1778 } 1779 1780 static int 1781 ipsec_iattach(const void *unused __unused) 1782 { 1783 INIT_VNET_IPSEC(curvnet); 1784 1785 SECPOLICY_LOCK_INIT(&V_ip4_def_policy); 1786 V_ip4_def_policy.refcnt = 1; /* NB: disallow free. */ 1787 1788 return (0); 1789 } 1790 SYSINIT(ipsec, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST, ipsec_attach, NULL); 1791 1792 1793 /* XXX This stuff doesn't belong here... */ 1794 1795 static struct xformsw* xforms = NULL; 1796 1797 /* 1798 * Register a transform; typically at system startup. 1799 */ 1800 void 1801 xform_register(struct xformsw* xsp) 1802 { 1803 1804 xsp->xf_next = xforms; 1805 xforms = xsp; 1806 } 1807 1808 /* 1809 * Initialize transform support in an sav. 1810 */ 1811 int 1812 xform_init(struct secasvar *sav, int xftype) 1813 { 1814 struct xformsw *xsp; 1815 1816 if (sav->tdb_xform != NULL) /* Previously initialized. */ 1817 return (0); 1818 for (xsp = xforms; xsp; xsp = xsp->xf_next) 1819 if (xsp->xf_type == xftype) 1820 return ((*xsp->xf_init)(sav, xsp)); 1821 return (EINVAL); 1822 } 1823