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 #ifdef VIMAGE 108 static int ipsec_idetach(const void *); 109 #endif 110 111 #ifdef VIMAGE_GLOBALS 112 /* NB: name changed so netstat doesn't use it. */ 113 struct ipsecstat ipsec4stat; 114 struct secpolicy ip4_def_policy; 115 int ipsec_debug; 116 int ip4_ah_offsetmask; 117 int ip4_ipsec_dfbit; 118 int ip4_esp_trans_deflev; 119 int ip4_esp_net_deflev; 120 int ip4_ah_trans_deflev; 121 int ip4_ah_net_deflev; 122 int ip4_ipsec_ecn; 123 int ip4_esp_randpad; 124 /* 125 * Crypto support requirements: 126 * 127 * 1 require hardware support 128 * -1 require software support 129 * 0 take anything 130 */ 131 int crypto_support; 132 #endif /* VIMAGE_GLOBALS */ 133 134 SYSCTL_DECL(_net_inet_ipsec); 135 136 /* net.inet.ipsec */ 137 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_POLICY, 138 def_policy, CTLFLAG_RW, ip4_def_policy.policy, 0, 139 "IPsec default policy."); 140 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, 141 esp_trans_deflev, CTLFLAG_RW, ip4_esp_trans_deflev, 0, 142 "Default ESP transport mode level"); 143 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, 144 esp_net_deflev, CTLFLAG_RW, ip4_esp_net_deflev, 0, 145 "Default ESP tunnel mode level."); 146 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, 147 ah_trans_deflev, CTLFLAG_RW, ip4_ah_trans_deflev, 0, 148 "AH transfer mode default level."); 149 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, 150 ah_net_deflev, CTLFLAG_RW, ip4_ah_net_deflev, 0, 151 "AH tunnel mode default level."); 152 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_AH_CLEARTOS, 153 ah_cleartos, CTLFLAG_RW, ah_cleartos, 0, 154 "If set clear type-of-service field when doing AH computation."); 155 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, 156 ah_offsetmask, CTLFLAG_RW, ip4_ah_offsetmask, 0, 157 "If not set clear offset field mask when doing AH computation."); 158 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DFBIT, 159 dfbit, CTLFLAG_RW, ip4_ipsec_dfbit, 0, 160 "Do not fragment bit on encap."); 161 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_ECN, 162 ecn, CTLFLAG_RW, ip4_ipsec_ecn, 0, 163 "Explicit Congestion Notification handling."); 164 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, IPSECCTL_DEBUG, 165 debug, CTLFLAG_RW, ipsec_debug, 0, 166 "Enable IPsec debugging output when set."); 167 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, OID_AUTO, 168 crypto_support, CTLFLAG_RW, crypto_support,0, 169 "Crypto driver selection."); 170 SYSCTL_V_STRUCT(V_NET, vnet_ipsec, _net_inet_ipsec, OID_AUTO, 171 ipsecstats, CTLFLAG_RD, ipsec4stat, ipsecstat, 172 "IPsec IPv4 statistics."); 173 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipsec, OID_AUTO, 174 filtertunnel, CTLFLAG_RW, ip4_ipsec_filtertunnel, 0, 175 "If set filter packets from an IPsec tunnel."); 176 177 #ifdef REGRESSION 178 #ifdef VIMAGE_GLOBALS 179 int ipsec_replay; 180 int ipsec_integrity; 181 #endif 182 /* 183 * When set to 1, IPsec will send packets with the same sequence number. 184 * This allows to verify if the other side has proper replay attacks detection. 185 */ 186 SYSCTL_V_INT(V_NET, vnet_ipsec,_net_inet_ipsec, OID_AUTO, test_replay, 187 CTLFLAG_RW, ipsec_replay, 0, "Emulate replay attack"); 188 /* 189 * When set 1, IPsec will send packets with corrupted HMAC. 190 * This allows to verify if the other side properly detects modified packets. 191 */ 192 SYSCTL_V_INT(V_NET, vnet_ipsec,_net_inet_ipsec, OID_AUTO, test_integrity, 193 CTLFLAG_RW, ipsec_integrity, 0, "Emulate man-in-the-middle attack"); 194 #endif 195 196 #ifdef INET6 197 #ifdef VIMAGE_GLOBALS 198 struct ipsecstat ipsec6stat; 199 int ip6_esp_trans_deflev; 200 int ip6_esp_net_deflev; 201 int ip6_ah_trans_deflev; 202 int ip6_ah_net_deflev; 203 int ip6_ipsec_ecn; 204 #endif 205 206 SYSCTL_DECL(_net_inet6_ipsec6); 207 208 /* net.inet6.ipsec6 */ 209 #ifdef COMPAT_KAME 210 SYSCTL_OID(_net_inet6_ipsec6, IPSECCTL_STATS, stats, CTLFLAG_RD, 211 0, 0, compat_ipsecstats_sysctl, "S", "IPsec IPv6 statistics."); 212 #endif /* COMPAT_KAME */ 213 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_POLICY, 214 def_policy, CTLFLAG_RW, ip4_def_policy.policy, 0, 215 "IPsec default policy."); 216 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV, 217 esp_trans_deflev, CTLFLAG_RW, ip6_esp_trans_deflev, 0, 218 "Default ESP transport mode level."); 219 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV, 220 esp_net_deflev, CTLFLAG_RW, ip6_esp_net_deflev, 0, 221 "Default ESP tunnel mode level."); 222 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV, 223 ah_trans_deflev, CTLFLAG_RW, ip6_ah_trans_deflev, 0, 224 "AH transfer mode default level."); 225 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV, 226 ah_net_deflev, CTLFLAG_RW, ip6_ah_net_deflev, 0, 227 "AH tunnel mode default level."); 228 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_ECN, 229 ecn, CTLFLAG_RW, ip6_ipsec_ecn, 0, 230 "Explicit Congestion Notification handling."); 231 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_DEBUG, 232 debug, CTLFLAG_RW, ipsec_debug, 0, 233 "Enable IPsec debugging output when set."); 234 SYSCTL_V_STRUCT(V_NET, vnet_ipsec, _net_inet6_ipsec6, IPSECCTL_STATS, 235 ipsecstats, CTLFLAG_RD, ipsec6stat, ipsecstat, 236 "IPsec IPv6 statistics."); 237 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet6_ipsec6, OID_AUTO, 238 filtertunnel, CTLFLAG_RW, ip6_ipsec6_filtertunnel, 0, 239 "If set filter packets from an IPsec tunnel."); 240 #endif /* INET6 */ 241 242 static int ipsec_setspidx_inpcb __P((struct mbuf *, struct inpcb *)); 243 static int ipsec_setspidx __P((struct mbuf *, struct secpolicyindex *, int)); 244 static void ipsec4_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 245 static int ipsec4_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 246 #ifdef INET6 247 static void ipsec6_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 248 static int ipsec6_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 249 #endif 250 static void ipsec_delpcbpolicy __P((struct inpcbpolicy *)); 251 static struct secpolicy *ipsec_deepcopy_policy __P((struct secpolicy *src)); 252 static void vshiftl __P((unsigned char *, int, int)); 253 254 MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy"); 255 256 #ifndef VIMAGE_GLOBALS 257 static const vnet_modinfo_t vnet_ipsec_modinfo = { 258 .vmi_id = VNET_MOD_IPSEC, 259 .vmi_name = "ipsec", 260 .vmi_size = sizeof(struct vnet_ipsec), 261 .vmi_dependson = VNET_MOD_INET, /* XXX revisit - INET6 ? */ 262 .vmi_iattach = ipsec_iattach, 263 #ifdef VIMAGE 264 .vmi_idetach = ipsec_idetach 265 #endif 266 }; 267 #endif /* !VIMAGE_GLOBALS */ 268 269 void 270 ipsec_init(void) 271 { 272 INIT_VNET_IPSEC(curvnet); 273 274 #ifdef IPSEC_DEBUG 275 V_ipsec_debug = 1; 276 #else 277 V_ipsec_debug = 0; 278 #endif 279 280 V_ip4_ah_offsetmask = 0; /* maybe IP_DF? */ 281 V_ip4_ipsec_dfbit = 0; /* DF bit on encap. 0: clear 1: set 2: copy */ 282 V_ip4_esp_trans_deflev = IPSEC_LEVEL_USE; 283 V_ip4_esp_net_deflev = IPSEC_LEVEL_USE; 284 V_ip4_ah_trans_deflev = IPSEC_LEVEL_USE; 285 V_ip4_ah_net_deflev = IPSEC_LEVEL_USE; 286 V_ip4_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 287 V_ip4_esp_randpad = -1; 288 #ifdef IPSEC_FILTERTUNNEL 289 V_ip4_ipsec_filtertunnel = 1; 290 #else 291 V_ip4_ipsec_filtertunnel = 0; 292 #endif 293 294 V_crypto_support = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE; 295 296 #ifdef REGRESSION 297 V_ipsec_replay = 0; 298 V_ipsec_integrity = 0; 299 #endif 300 301 #ifdef INET6 302 V_ip6_esp_trans_deflev = IPSEC_LEVEL_USE; 303 V_ip6_esp_net_deflev = IPSEC_LEVEL_USE; 304 V_ip6_ah_trans_deflev = IPSEC_LEVEL_USE; 305 V_ip6_ah_net_deflev = IPSEC_LEVEL_USE; 306 V_ip6_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 307 #ifdef IPSEC_FILTERTUNNEL 308 V_ip6_ipsec6_filtertunnel = 1; 309 #else 310 V_ip6_ipsec6_filtertunnel = 0; 311 #endif 312 #endif 313 } 314 315 /* 316 * Return a held reference to the default SP. 317 */ 318 static struct secpolicy * 319 key_allocsp_default(const char* where, int tag) 320 { 321 INIT_VNET_IPSEC(curvnet); 322 struct secpolicy *sp; 323 324 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 325 printf("DP key_allocsp_default from %s:%u\n", where, tag)); 326 327 sp = &V_ip4_def_policy; 328 if (sp->policy != IPSEC_POLICY_DISCARD && 329 sp->policy != IPSEC_POLICY_NONE) { 330 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n", 331 sp->policy, IPSEC_POLICY_NONE)); 332 sp->policy = IPSEC_POLICY_NONE; 333 } 334 key_addref(sp); 335 336 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 337 printf("DP key_allocsp_default returns SP:%p (%u)\n", 338 sp, sp->refcnt)); 339 return (sp); 340 } 341 #define KEY_ALLOCSP_DEFAULT() \ 342 key_allocsp_default(__FILE__, __LINE__) 343 344 /* 345 * For OUTBOUND packet having a socket. Searching SPD for packet, 346 * and return a pointer to SP. 347 * OUT: NULL: no apropreate SP found, the following value is set to error. 348 * 0 : bypass 349 * EACCES : discard packet. 350 * ENOENT : ipsec_acquire() in progress, maybe. 351 * others : error occured. 352 * others: a pointer to SP 353 * 354 * NOTE: IPv6 mapped adddress concern is implemented here. 355 */ 356 struct secpolicy * 357 ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir) 358 { 359 struct secpolicy *sp; 360 361 IPSEC_ASSERT(tdbi != NULL, ("null tdbi")); 362 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 363 ("invalid direction %u", dir)); 364 365 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir); 366 if (sp == NULL) /*XXX????*/ 367 sp = KEY_ALLOCSP_DEFAULT(); 368 IPSEC_ASSERT(sp != NULL, ("null SP")); 369 return (sp); 370 } 371 372 /* 373 * For OUTBOUND packet having a socket. Searching SPD for packet, 374 * and return a pointer to SP. 375 * OUT: NULL: no apropreate SP found, the following value is set to error. 376 * 0 : bypass 377 * EACCES : discard packet. 378 * ENOENT : ipsec_acquire() in progress, maybe. 379 * others : error occured. 380 * others: a pointer to SP 381 * 382 * NOTE: IPv6 mapped adddress concern is implemented here. 383 */ 384 static struct secpolicy * 385 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb *inp, int *error) 386 { 387 INIT_VNET_IPSEC(curvnet); 388 struct inpcbpolicy *pcbsp; 389 struct secpolicy *currsp = NULL; /* Policy on socket. */ 390 struct secpolicy *sp; 391 392 IPSEC_ASSERT(m != NULL, ("null mbuf")); 393 IPSEC_ASSERT(inp != NULL, ("null inpcb")); 394 IPSEC_ASSERT(error != NULL, ("null error")); 395 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 396 ("invalid direction %u", dir)); 397 398 /* Set spidx in pcb. */ 399 *error = ipsec_setspidx_inpcb(m, inp); 400 if (*error) 401 return (NULL); 402 403 pcbsp = inp->inp_sp; 404 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp")); 405 switch (dir) { 406 case IPSEC_DIR_INBOUND: 407 currsp = pcbsp->sp_in; 408 break; 409 case IPSEC_DIR_OUTBOUND: 410 currsp = pcbsp->sp_out; 411 break; 412 } 413 IPSEC_ASSERT(currsp != NULL, ("null currsp")); 414 415 if (pcbsp->priv) { /* When privilieged socket. */ 416 switch (currsp->policy) { 417 case IPSEC_POLICY_BYPASS: 418 case IPSEC_POLICY_IPSEC: 419 key_addref(currsp); 420 sp = currsp; 421 break; 422 423 case IPSEC_POLICY_ENTRUST: 424 /* Look for a policy in SPD. */ 425 sp = KEY_ALLOCSP(&currsp->spidx, dir); 426 if (sp == NULL) /* No SP found. */ 427 sp = KEY_ALLOCSP_DEFAULT(); 428 break; 429 430 default: 431 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n", 432 __func__, currsp->policy)); 433 *error = EINVAL; 434 return (NULL); 435 } 436 } else { /* Unpriv, SPD has policy. */ 437 sp = KEY_ALLOCSP(&currsp->spidx, dir); 438 if (sp == NULL) { /* No SP found. */ 439 switch (currsp->policy) { 440 case IPSEC_POLICY_BYPASS: 441 ipseclog((LOG_ERR, "%s: Illegal policy for " 442 "non-priviliged defined %d\n", 443 __func__, currsp->policy)); 444 *error = EINVAL; 445 return (NULL); 446 447 case IPSEC_POLICY_ENTRUST: 448 sp = KEY_ALLOCSP_DEFAULT(); 449 break; 450 451 case IPSEC_POLICY_IPSEC: 452 key_addref(currsp); 453 sp = currsp; 454 break; 455 456 default: 457 ipseclog((LOG_ERR, "%s: Invalid policy for " 458 "PCB %d\n", __func__, currsp->policy)); 459 *error = EINVAL; 460 return (NULL); 461 } 462 } 463 } 464 IPSEC_ASSERT(sp != NULL, 465 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy)); 466 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 467 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n", 468 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt)); 469 return (sp); 470 } 471 472 /* 473 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 474 * and return a pointer to SP. 475 * OUT: positive: a pointer to the entry for security policy leaf matched. 476 * NULL: no apropreate SP found, the following value is set to error. 477 * 0 : bypass 478 * EACCES : discard packet. 479 * ENOENT : ipsec_acquire() in progress, maybe. 480 * others : error occured. 481 */ 482 struct secpolicy * 483 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 484 { 485 INIT_VNET_IPSEC(curvnet); 486 struct secpolicyindex spidx; 487 struct secpolicy *sp; 488 489 IPSEC_ASSERT(m != NULL, ("null mbuf")); 490 IPSEC_ASSERT(error != NULL, ("null error")); 491 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 492 ("invalid direction %u", dir)); 493 494 sp = NULL; 495 if (key_havesp(dir)) { 496 /* Make an index to look for a policy. */ 497 *error = ipsec_setspidx(m, &spidx, 498 (flag & IP_FORWARDING) ? 0 : 1); 499 if (*error != 0) { 500 DPRINTF(("%s: setpidx failed, dir %u flag %u\n", 501 __func__, dir, flag)); 502 return (NULL); 503 } 504 spidx.dir = dir; 505 506 sp = KEY_ALLOCSP(&spidx, dir); 507 } 508 if (sp == NULL) /* No SP found, use system default. */ 509 sp = KEY_ALLOCSP_DEFAULT(); 510 IPSEC_ASSERT(sp != NULL, ("null SP")); 511 return (sp); 512 } 513 514 struct secpolicy * 515 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 516 struct inpcb *inp) 517 { 518 INIT_VNET_IPSEC(curvnet); 519 struct secpolicy *sp; 520 521 *error = 0; 522 if (inp == NULL) 523 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 524 else 525 sp = ipsec_getpolicybysock(m, dir, inp, error); 526 if (sp == NULL) { 527 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error")); 528 V_ipsec4stat.ips_out_inval++; 529 return (NULL); 530 } 531 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error)); 532 switch (sp->policy) { 533 case IPSEC_POLICY_ENTRUST: 534 default: 535 printf("%s: invalid policy %u\n", __func__, sp->policy); 536 /* FALLTHROUGH */ 537 case IPSEC_POLICY_DISCARD: 538 V_ipsec4stat.ips_out_polvio++; 539 *error = -EINVAL; /* Packet is discarded by caller. */ 540 break; 541 case IPSEC_POLICY_BYPASS: 542 case IPSEC_POLICY_NONE: 543 KEY_FREESP(&sp); 544 sp = NULL; /* NB: force NULL result. */ 545 break; 546 case IPSEC_POLICY_IPSEC: 547 if (sp->req == NULL) /* Acquire a SA. */ 548 *error = key_spdacquire(sp); 549 break; 550 } 551 if (*error != 0) { 552 KEY_FREESP(&sp); 553 sp = NULL; 554 } 555 return (sp); 556 } 557 558 static int 559 ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp) 560 { 561 int error; 562 563 IPSEC_ASSERT(inp != NULL, ("null inp")); 564 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 565 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL, 566 ("null sp_in || sp_out")); 567 568 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1); 569 if (error == 0) { 570 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 571 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx; 572 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 573 } else { 574 bzero(&inp->inp_sp->sp_in->spidx, 575 sizeof (inp->inp_sp->sp_in->spidx)); 576 bzero(&inp->inp_sp->sp_out->spidx, 577 sizeof (inp->inp_sp->sp_in->spidx)); 578 } 579 return (error); 580 } 581 582 /* 583 * Configure security policy index (src/dst/proto/sport/dport) 584 * by looking at the content of mbuf. 585 * The caller is responsible for error recovery (like clearing up spidx). 586 */ 587 static int 588 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 589 { 590 INIT_VNET_IPSEC(curvnet); 591 struct ip *ip = NULL; 592 struct ip ipbuf; 593 u_int v; 594 struct mbuf *n; 595 int len; 596 int error; 597 598 IPSEC_ASSERT(m != NULL, ("null mbuf")); 599 600 /* 601 * Validate m->m_pkthdr.len. We see incorrect length if we 602 * mistakenly call this function with inconsistent mbuf chain 603 * (like 4.4BSD tcp/udp processing). XXX Should we panic here? 604 */ 605 len = 0; 606 for (n = m; n; n = n->m_next) 607 len += n->m_len; 608 if (m->m_pkthdr.len != len) { 609 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 610 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n", 611 __func__, len, m->m_pkthdr.len)); 612 return (EINVAL); 613 } 614 615 if (m->m_pkthdr.len < sizeof(struct ip)) { 616 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 617 printf("%s: pkthdr len(%d) too small (v4), ignored.\n", 618 __func__, m->m_pkthdr.len)); 619 return (EINVAL); 620 } 621 622 if (m->m_len >= sizeof(*ip)) 623 ip = mtod(m, struct ip *); 624 else { 625 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf); 626 ip = &ipbuf; 627 } 628 #ifdef _IP_VHL 629 v = _IP_VHL_V(ip->ip_vhl); 630 #else 631 v = ip->ip_v; 632 #endif 633 switch (v) { 634 case 4: 635 error = ipsec4_setspidx_ipaddr(m, spidx); 636 if (error) 637 return (error); 638 ipsec4_get_ulp(m, spidx, needport); 639 return (0); 640 #ifdef INET6 641 case 6: 642 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 643 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 644 printf("%s: pkthdr len(%d) too small (v6), " 645 "ignored\n", __func__, m->m_pkthdr.len)); 646 return (EINVAL); 647 } 648 error = ipsec6_setspidx_ipaddr(m, spidx); 649 if (error) 650 return (error); 651 ipsec6_get_ulp(m, spidx, needport); 652 return (0); 653 #endif 654 default: 655 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 656 printf("%s: " "unknown IP version %u, ignored.\n", 657 __func__, v)); 658 return (EINVAL); 659 } 660 } 661 662 static void 663 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 664 { 665 u_int8_t nxt; 666 int off; 667 668 /* Sanity check. */ 669 IPSEC_ASSERT(m != NULL, ("null mbuf")); 670 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short")); 671 672 /* NB: ip_input() flips it into host endian. XXX Need more checking. */ 673 if (m->m_len < sizeof (struct ip)) { 674 struct ip *ip = mtod(m, struct ip *); 675 if (ip->ip_off & (IP_MF | IP_OFFMASK)) 676 goto done; 677 #ifdef _IP_VHL 678 off = _IP_VHL_HL(ip->ip_vhl) << 2; 679 #else 680 off = ip->ip_hl << 2; 681 #endif 682 nxt = ip->ip_p; 683 } else { 684 struct ip ih; 685 686 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih); 687 if (ih.ip_off & (IP_MF | IP_OFFMASK)) 688 goto done; 689 #ifdef _IP_VHL 690 off = _IP_VHL_HL(ih.ip_vhl) << 2; 691 #else 692 off = ih.ip_hl << 2; 693 #endif 694 nxt = ih.ip_p; 695 } 696 697 while (off < m->m_pkthdr.len) { 698 struct ip6_ext ip6e; 699 struct tcphdr th; 700 struct udphdr uh; 701 702 switch (nxt) { 703 case IPPROTO_TCP: 704 spidx->ul_proto = nxt; 705 if (!needport) 706 goto done_proto; 707 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 708 goto done; 709 m_copydata(m, off, sizeof (th), (caddr_t) &th); 710 spidx->src.sin.sin_port = th.th_sport; 711 spidx->dst.sin.sin_port = th.th_dport; 712 return; 713 case IPPROTO_UDP: 714 spidx->ul_proto = nxt; 715 if (!needport) 716 goto done_proto; 717 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 718 goto done; 719 m_copydata(m, off, sizeof (uh), (caddr_t) &uh); 720 spidx->src.sin.sin_port = uh.uh_sport; 721 spidx->dst.sin.sin_port = uh.uh_dport; 722 return; 723 case IPPROTO_AH: 724 if (off + sizeof(ip6e) > m->m_pkthdr.len) 725 goto done; 726 /* XXX Sigh, this works but is totally bogus. */ 727 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e); 728 off += (ip6e.ip6e_len + 2) << 2; 729 nxt = ip6e.ip6e_nxt; 730 break; 731 case IPPROTO_ICMP: 732 default: 733 /* XXX Intermediate headers??? */ 734 spidx->ul_proto = nxt; 735 goto done_proto; 736 } 737 } 738 done: 739 spidx->ul_proto = IPSEC_ULPROTO_ANY; 740 done_proto: 741 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 742 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 743 } 744 745 /* Assumes that m is sane. */ 746 static int 747 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 748 { 749 static const struct sockaddr_in template = { 750 sizeof (struct sockaddr_in), 751 AF_INET, 752 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 753 }; 754 755 spidx->src.sin = template; 756 spidx->dst.sin = template; 757 758 if (m->m_len < sizeof (struct ip)) { 759 m_copydata(m, offsetof(struct ip, ip_src), 760 sizeof (struct in_addr), 761 (caddr_t) &spidx->src.sin.sin_addr); 762 m_copydata(m, offsetof(struct ip, ip_dst), 763 sizeof (struct in_addr), 764 (caddr_t) &spidx->dst.sin.sin_addr); 765 } else { 766 struct ip *ip = mtod(m, struct ip *); 767 spidx->src.sin.sin_addr = ip->ip_src; 768 spidx->dst.sin.sin_addr = ip->ip_dst; 769 } 770 771 spidx->prefs = sizeof(struct in_addr) << 3; 772 spidx->prefd = sizeof(struct in_addr) << 3; 773 774 return (0); 775 } 776 777 #ifdef INET6 778 static void 779 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 780 { 781 INIT_VNET_IPSEC(curvnet); 782 int off, nxt; 783 struct tcphdr th; 784 struct udphdr uh; 785 struct icmp6_hdr ih; 786 787 /* Sanity check. */ 788 if (m == NULL) 789 panic("%s: NULL pointer was passed.\n", __func__); 790 791 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 792 printf("%s:\n", __func__); kdebug_mbuf(m)); 793 794 /* Set default. */ 795 spidx->ul_proto = IPSEC_ULPROTO_ANY; 796 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 797 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 798 799 nxt = -1; 800 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 801 if (off < 0 || m->m_pkthdr.len < off) 802 return; 803 804 switch (nxt) { 805 case IPPROTO_TCP: 806 spidx->ul_proto = nxt; 807 if (!needport) 808 break; 809 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 810 break; 811 m_copydata(m, off, sizeof(th), (caddr_t)&th); 812 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 813 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 814 break; 815 case IPPROTO_UDP: 816 spidx->ul_proto = nxt; 817 if (!needport) 818 break; 819 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 820 break; 821 m_copydata(m, off, sizeof(uh), (caddr_t)&uh); 822 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 823 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 824 break; 825 case IPPROTO_ICMPV6: 826 spidx->ul_proto = nxt; 827 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 828 break; 829 m_copydata(m, off, sizeof(ih), (caddr_t)&ih); 830 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 831 htons((uint16_t)ih.icmp6_type); 832 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 833 htons((uint16_t)ih.icmp6_code); 834 break; 835 default: 836 /* XXX Intermediate headers??? */ 837 spidx->ul_proto = nxt; 838 break; 839 } 840 } 841 842 /* Assumes that m is sane. */ 843 static int 844 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 845 { 846 struct ip6_hdr *ip6 = NULL; 847 struct ip6_hdr ip6buf; 848 struct sockaddr_in6 *sin6; 849 850 if (m->m_len >= sizeof(*ip6)) 851 ip6 = mtod(m, struct ip6_hdr *); 852 else { 853 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf); 854 ip6 = &ip6buf; 855 } 856 857 sin6 = (struct sockaddr_in6 *)&spidx->src; 858 bzero(sin6, sizeof(*sin6)); 859 sin6->sin6_family = AF_INET6; 860 sin6->sin6_len = sizeof(struct sockaddr_in6); 861 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src)); 862 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 863 sin6->sin6_addr.s6_addr16[1] = 0; 864 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 865 } 866 spidx->prefs = sizeof(struct in6_addr) << 3; 867 868 sin6 = (struct sockaddr_in6 *)&spidx->dst; 869 bzero(sin6, sizeof(*sin6)); 870 sin6->sin6_family = AF_INET6; 871 sin6->sin6_len = sizeof(struct sockaddr_in6); 872 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst)); 873 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 874 sin6->sin6_addr.s6_addr16[1] = 0; 875 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 876 } 877 spidx->prefd = sizeof(struct in6_addr) << 3; 878 879 return (0); 880 } 881 #endif 882 883 static void 884 ipsec_delpcbpolicy(struct inpcbpolicy *p) 885 { 886 887 free(p, M_IPSEC_INPCB); 888 } 889 890 /* Initialize policy in PCB. */ 891 int 892 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp) 893 { 894 INIT_VNET_IPSEC(curvnet); 895 struct inpcbpolicy *new; 896 897 /* Sanity check. */ 898 if (so == NULL || pcb_sp == NULL) 899 panic("%s: NULL pointer was passed.\n", __func__); 900 901 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy), 902 M_IPSEC_INPCB, M_NOWAIT|M_ZERO); 903 if (new == NULL) { 904 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 905 return (ENOBUFS); 906 } 907 908 new->priv = IPSEC_IS_PRIVILEGED_SO(so); 909 910 if ((new->sp_in = KEY_NEWSP()) == NULL) { 911 ipsec_delpcbpolicy(new); 912 return (ENOBUFS); 913 } 914 new->sp_in->state = IPSEC_SPSTATE_ALIVE; 915 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 916 917 if ((new->sp_out = KEY_NEWSP()) == NULL) { 918 KEY_FREESP(&new->sp_in); 919 ipsec_delpcbpolicy(new); 920 return (ENOBUFS); 921 } 922 new->sp_out->state = IPSEC_SPSTATE_ALIVE; 923 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 924 925 *pcb_sp = new; 926 927 return (0); 928 } 929 930 /* Copy old IPsec policy into new. */ 931 int 932 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new) 933 { 934 struct secpolicy *sp; 935 936 sp = ipsec_deepcopy_policy(old->sp_in); 937 if (sp) { 938 KEY_FREESP(&new->sp_in); 939 new->sp_in = sp; 940 } else 941 return (ENOBUFS); 942 943 sp = ipsec_deepcopy_policy(old->sp_out); 944 if (sp) { 945 KEY_FREESP(&new->sp_out); 946 new->sp_out = sp; 947 } else 948 return (ENOBUFS); 949 950 new->priv = old->priv; 951 952 return (0); 953 } 954 955 struct ipsecrequest * 956 ipsec_newisr(void) 957 { 958 struct ipsecrequest *p; 959 960 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO); 961 if (p != NULL) 962 IPSECREQUEST_LOCK_INIT(p); 963 return (p); 964 } 965 966 void 967 ipsec_delisr(struct ipsecrequest *p) 968 { 969 970 IPSECREQUEST_LOCK_DESTROY(p); 971 free(p, M_IPSEC_SR); 972 } 973 974 /* Deep-copy a policy in PCB. */ 975 static struct secpolicy * 976 ipsec_deepcopy_policy(struct secpolicy *src) 977 { 978 struct ipsecrequest *newchain = NULL; 979 struct ipsecrequest *p; 980 struct ipsecrequest **q; 981 struct ipsecrequest *r; 982 struct secpolicy *dst; 983 984 if (src == NULL) 985 return (NULL); 986 dst = KEY_NEWSP(); 987 if (dst == NULL) 988 return (NULL); 989 990 /* 991 * Deep-copy IPsec request chain. This is required since struct 992 * ipsecrequest is not reference counted. 993 */ 994 q = &newchain; 995 for (p = src->req; p; p = p->next) { 996 *q = ipsec_newisr(); 997 if (*q == NULL) 998 goto fail; 999 (*q)->saidx.proto = p->saidx.proto; 1000 (*q)->saidx.mode = p->saidx.mode; 1001 (*q)->level = p->level; 1002 (*q)->saidx.reqid = p->saidx.reqid; 1003 1004 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src)); 1005 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst)); 1006 1007 (*q)->sp = dst; 1008 1009 q = &((*q)->next); 1010 } 1011 1012 dst->req = newchain; 1013 dst->state = src->state; 1014 dst->policy = src->policy; 1015 /* Do not touch the refcnt fields. */ 1016 1017 return (dst); 1018 1019 fail: 1020 for (p = newchain; p; p = r) { 1021 r = p->next; 1022 ipsec_delisr(p); 1023 p = NULL; 1024 } 1025 return (NULL); 1026 } 1027 1028 /* Set policy and IPsec request if present. */ 1029 static int 1030 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname, 1031 caddr_t request, size_t len, struct ucred *cred) 1032 { 1033 INIT_VNET_IPSEC(curvnet); 1034 struct sadb_x_policy *xpl; 1035 struct secpolicy *newsp = NULL; 1036 int error; 1037 1038 /* Sanity check. */ 1039 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL) 1040 return (EINVAL); 1041 if (len < sizeof(*xpl)) 1042 return (EINVAL); 1043 xpl = (struct sadb_x_policy *)request; 1044 1045 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1046 printf("%s: passed policy\n", __func__); 1047 kdebug_sadb_x_policy((struct sadb_ext *)xpl)); 1048 1049 /* Check policy type. */ 1050 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */ 1051 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 1052 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 1053 return (EINVAL); 1054 1055 /* Check privileged socket. */ 1056 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 1057 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0); 1058 if (error) 1059 return (EACCES); 1060 } 1061 1062 /* Allocating new SP entry. */ 1063 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 1064 return (error); 1065 1066 newsp->state = IPSEC_SPSTATE_ALIVE; 1067 1068 /* Clear old SP and set new SP. */ 1069 KEY_FREESP(pcb_sp); 1070 *pcb_sp = newsp; 1071 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1072 printf("%s: new policy\n", __func__); 1073 kdebug_secpolicy(newsp)); 1074 1075 return (0); 1076 } 1077 1078 int 1079 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request, 1080 size_t len, struct ucred *cred) 1081 { 1082 INIT_VNET_IPSEC(curvnet); 1083 struct sadb_x_policy *xpl; 1084 struct secpolicy **pcb_sp; 1085 1086 /* Sanity check. */ 1087 if (inp == NULL || request == NULL) 1088 return (EINVAL); 1089 if (len < sizeof(*xpl)) 1090 return (EINVAL); 1091 xpl = (struct sadb_x_policy *)request; 1092 1093 /* Select direction. */ 1094 switch (xpl->sadb_x_policy_dir) { 1095 case IPSEC_DIR_INBOUND: 1096 pcb_sp = &inp->inp_sp->sp_in; 1097 break; 1098 case IPSEC_DIR_OUTBOUND: 1099 pcb_sp = &inp->inp_sp->sp_out; 1100 break; 1101 default: 1102 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1103 xpl->sadb_x_policy_dir)); 1104 return (EINVAL); 1105 } 1106 1107 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred)); 1108 } 1109 1110 int 1111 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len, 1112 struct mbuf **mp) 1113 { 1114 INIT_VNET_IPSEC(curvnet); 1115 struct sadb_x_policy *xpl; 1116 struct secpolicy *pcb_sp; 1117 1118 /* Sanity check. */ 1119 if (inp == NULL || request == NULL || mp == NULL) 1120 return (EINVAL); 1121 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 1122 if (len < sizeof(*xpl)) 1123 return (EINVAL); 1124 xpl = (struct sadb_x_policy *)request; 1125 1126 /* Select direction. */ 1127 switch (xpl->sadb_x_policy_dir) { 1128 case IPSEC_DIR_INBOUND: 1129 pcb_sp = inp->inp_sp->sp_in; 1130 break; 1131 case IPSEC_DIR_OUTBOUND: 1132 pcb_sp = inp->inp_sp->sp_out; 1133 break; 1134 default: 1135 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1136 xpl->sadb_x_policy_dir)); 1137 return (EINVAL); 1138 } 1139 1140 /* Sanity check. Should be an IPSEC_ASSERT. */ 1141 if (pcb_sp == NULL) 1142 return (EINVAL); 1143 1144 *mp = key_sp2msg(pcb_sp); 1145 if (!*mp) { 1146 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 1147 return (ENOBUFS); 1148 } 1149 1150 (*mp)->m_type = MT_DATA; 1151 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1152 printf("%s:\n", __func__); kdebug_mbuf(*mp)); 1153 1154 return (0); 1155 } 1156 1157 /* Delete policy in PCB. */ 1158 int 1159 ipsec_delete_pcbpolicy(struct inpcb *inp) 1160 { 1161 IPSEC_ASSERT(inp != NULL, ("null inp")); 1162 1163 if (inp->inp_sp == NULL) 1164 return (0); 1165 1166 if (inp->inp_sp->sp_in != NULL) 1167 KEY_FREESP(&inp->inp_sp->sp_in); 1168 1169 if (inp->inp_sp->sp_out != NULL) 1170 KEY_FREESP(&inp->inp_sp->sp_out); 1171 1172 ipsec_delpcbpolicy(inp->inp_sp); 1173 inp->inp_sp = NULL; 1174 1175 return (0); 1176 } 1177 1178 /* 1179 * Return current level. 1180 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1181 */ 1182 u_int 1183 ipsec_get_reqlevel(struct ipsecrequest *isr) 1184 { 1185 INIT_VNET_IPSEC(curvnet); 1186 u_int level = 0; 1187 u_int esp_trans_deflev, esp_net_deflev; 1188 u_int ah_trans_deflev, ah_net_deflev; 1189 1190 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument")); 1191 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1192 ("af family mismatch, src %u, dst %u", 1193 isr->sp->spidx.src.sa.sa_family, 1194 isr->sp->spidx.dst.sa.sa_family)); 1195 1196 /* XXX Note that we have ipseclog() expanded here - code sync issue. */ 1197 #define IPSEC_CHECK_DEFAULT(lev) \ 1198 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1199 && (lev) != IPSEC_LEVEL_UNIQUE) \ 1200 ? (V_ipsec_debug \ 1201 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\ 1202 (lev), IPSEC_LEVEL_REQUIRE) \ 1203 : 0), \ 1204 (lev) = IPSEC_LEVEL_REQUIRE, \ 1205 (lev) \ 1206 : (lev)) 1207 1208 /* Set default level. */ 1209 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1210 #ifdef INET 1211 case AF_INET: 1212 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev); 1213 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev); 1214 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev); 1215 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev); 1216 break; 1217 #endif 1218 #ifdef INET6 1219 case AF_INET6: 1220 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev); 1221 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev); 1222 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev); 1223 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev); 1224 break; 1225 #endif /* INET6 */ 1226 default: 1227 panic("%s: unknown af %u", 1228 __func__, isr->sp->spidx.src.sa.sa_family); 1229 } 1230 1231 #undef IPSEC_CHECK_DEFAULT 1232 1233 /* Set level. */ 1234 switch (isr->level) { 1235 case IPSEC_LEVEL_DEFAULT: 1236 switch (isr->saidx.proto) { 1237 case IPPROTO_ESP: 1238 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1239 level = esp_net_deflev; 1240 else 1241 level = esp_trans_deflev; 1242 break; 1243 case IPPROTO_AH: 1244 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1245 level = ah_net_deflev; 1246 else 1247 level = ah_trans_deflev; 1248 break; 1249 case IPPROTO_IPCOMP: 1250 /* 1251 * We don't really care, as IPcomp document says that 1252 * we shouldn't compress small packets. 1253 */ 1254 level = IPSEC_LEVEL_USE; 1255 break; 1256 default: 1257 panic("%s: Illegal protocol defined %u\n", __func__, 1258 isr->saidx.proto); 1259 } 1260 break; 1261 1262 case IPSEC_LEVEL_USE: 1263 case IPSEC_LEVEL_REQUIRE: 1264 level = isr->level; 1265 break; 1266 case IPSEC_LEVEL_UNIQUE: 1267 level = IPSEC_LEVEL_REQUIRE; 1268 break; 1269 1270 default: 1271 panic("%s: Illegal IPsec level %u\n", __func__, isr->level); 1272 } 1273 1274 return (level); 1275 } 1276 1277 /* 1278 * Check security policy requirements against the actual 1279 * packet contents. Return one if the packet should be 1280 * reject as "invalid"; otherwiser return zero to have the 1281 * packet treated as "valid". 1282 * 1283 * OUT: 1284 * 0: valid 1285 * 1: invalid 1286 */ 1287 int 1288 ipsec_in_reject(struct secpolicy *sp, struct mbuf *m) 1289 { 1290 INIT_VNET_IPSEC(curvnet); 1291 struct ipsecrequest *isr; 1292 int need_auth; 1293 1294 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1295 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1296 1297 /* Check policy. */ 1298 switch (sp->policy) { 1299 case IPSEC_POLICY_DISCARD: 1300 return (1); 1301 case IPSEC_POLICY_BYPASS: 1302 case IPSEC_POLICY_NONE: 1303 return (0); 1304 } 1305 1306 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1307 ("invalid policy %u", sp->policy)); 1308 1309 /* XXX Should compare policy against IPsec header history. */ 1310 1311 need_auth = 0; 1312 for (isr = sp->req; isr != NULL; isr = isr->next) { 1313 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1314 continue; 1315 switch (isr->saidx.proto) { 1316 case IPPROTO_ESP: 1317 if ((m->m_flags & M_DECRYPTED) == 0) { 1318 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1319 printf("%s: ESP m_flags:%x\n", __func__, 1320 m->m_flags)); 1321 return (1); 1322 } 1323 1324 if (!need_auth && 1325 isr->sav != NULL && 1326 isr->sav->tdb_authalgxform != NULL && 1327 (m->m_flags & M_AUTHIPDGM) == 0) { 1328 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1329 printf("%s: ESP/AH m_flags:%x\n", __func__, 1330 m->m_flags)); 1331 return (1); 1332 } 1333 break; 1334 case IPPROTO_AH: 1335 need_auth = 1; 1336 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1337 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1338 printf("%s: AH m_flags:%x\n", __func__, 1339 m->m_flags)); 1340 return (1); 1341 } 1342 break; 1343 case IPPROTO_IPCOMP: 1344 /* 1345 * We don't really care, as IPcomp document 1346 * says that we shouldn't compress small 1347 * packets. IPComp policy should always be 1348 * treated as being in "use" level. 1349 */ 1350 break; 1351 } 1352 } 1353 return (0); /* Valid. */ 1354 } 1355 1356 static int 1357 ipsec46_in_reject(struct mbuf *m, struct inpcb *inp) 1358 { 1359 struct secpolicy *sp; 1360 int error; 1361 int result; 1362 1363 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1364 1365 /* 1366 * Get SP for this packet. 1367 * When we are called from ip_forward(), we call 1368 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1369 */ 1370 if (inp == NULL) 1371 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1372 else 1373 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error); 1374 1375 if (sp != NULL) { 1376 result = ipsec_in_reject(sp, m); 1377 KEY_FREESP(&sp); 1378 } else { 1379 result = 0; /* XXX Should be panic? 1380 * -> No, there may be error. */ 1381 } 1382 return (result); 1383 } 1384 1385 /* 1386 * Check AH/ESP integrity. 1387 * This function is called from tcp_input(), udp_input(), 1388 * and {ah,esp}4_input for tunnel mode. 1389 */ 1390 int 1391 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1392 { 1393 INIT_VNET_IPSEC(curvnet); 1394 int result; 1395 1396 result = ipsec46_in_reject(m, inp); 1397 if (result) 1398 V_ipsec4stat.ips_in_polvio++; 1399 1400 return (result); 1401 } 1402 1403 #ifdef INET6 1404 /* 1405 * Check AH/ESP integrity. 1406 * This function is called from tcp6_input(), udp6_input(), 1407 * and {ah,esp}6_input for tunnel mode. 1408 */ 1409 int 1410 ipsec6_in_reject(struct mbuf *m, struct inpcb *inp) 1411 { 1412 INIT_VNET_IPSEC(curvnet); 1413 int result; 1414 1415 result = ipsec46_in_reject(m, inp); 1416 if (result) 1417 V_ipsec6stat.ips_in_polvio++; 1418 1419 return (result); 1420 } 1421 #endif 1422 1423 /* 1424 * Compute the byte size to be occupied by IPsec header. 1425 * In case it is tunnelled, it includes the size of outer IP header. 1426 * NOTE: SP passed is freed in this function. 1427 */ 1428 static size_t 1429 ipsec_hdrsiz_internal(struct secpolicy *sp) 1430 { 1431 INIT_VNET_IPSEC(curvnet); 1432 struct ipsecrequest *isr; 1433 size_t size; 1434 1435 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1436 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1437 1438 switch (sp->policy) { 1439 case IPSEC_POLICY_DISCARD: 1440 case IPSEC_POLICY_BYPASS: 1441 case IPSEC_POLICY_NONE: 1442 return (0); 1443 } 1444 1445 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1446 ("invalid policy %u", sp->policy)); 1447 1448 size = 0; 1449 for (isr = sp->req; isr != NULL; isr = isr->next) { 1450 size_t clen = 0; 1451 1452 switch (isr->saidx.proto) { 1453 case IPPROTO_ESP: 1454 clen = esp_hdrsiz(isr->sav); 1455 break; 1456 case IPPROTO_AH: 1457 clen = ah_hdrsiz(isr->sav); 1458 break; 1459 case IPPROTO_IPCOMP: 1460 clen = sizeof(struct ipcomp); 1461 break; 1462 } 1463 1464 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1465 switch (isr->saidx.dst.sa.sa_family) { 1466 case AF_INET: 1467 clen += sizeof(struct ip); 1468 break; 1469 #ifdef INET6 1470 case AF_INET6: 1471 clen += sizeof(struct ip6_hdr); 1472 break; 1473 #endif 1474 default: 1475 ipseclog((LOG_ERR, "%s: unknown AF %d in " 1476 "IPsec tunnel SA\n", __func__, 1477 ((struct sockaddr *)&isr->saidx.dst)->sa_family)); 1478 break; 1479 } 1480 } 1481 size += clen; 1482 } 1483 1484 return (size); 1485 } 1486 1487 /* 1488 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(), 1489 * disabled ip6_ipsec_mtu() and ip6_forward(). 1490 */ 1491 size_t 1492 ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1493 { 1494 INIT_VNET_IPSEC(curvnet); 1495 struct secpolicy *sp; 1496 int error; 1497 size_t size; 1498 1499 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1500 1501 /* Get SP for this packet. 1502 * When we are called from ip_forward(), we call 1503 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1504 */ 1505 if (inp == NULL) 1506 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1507 else 1508 sp = ipsec_getpolicybysock(m, dir, inp, &error); 1509 1510 if (sp != NULL) { 1511 size = ipsec_hdrsiz_internal(sp); 1512 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1513 printf("%s: size:%lu.\n", __func__, 1514 (unsigned long)size)); 1515 1516 KEY_FREESP(&sp); 1517 } else { 1518 size = 0; /* XXX Should be panic? 1519 * -> No, we are called w/o knowing if 1520 * IPsec processing is needed. */ 1521 } 1522 return (size); 1523 } 1524 1525 /* 1526 * Check the variable replay window. 1527 * ipsec_chkreplay() performs replay check before ICV verification. 1528 * ipsec_updatereplay() updates replay bitmap. This must be called after 1529 * ICV verification (it also performs replay check, which is usually done 1530 * beforehand). 1531 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1532 * 1533 * Based on RFC 2401. 1534 */ 1535 int 1536 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav) 1537 { 1538 const struct secreplay *replay; 1539 u_int32_t diff; 1540 int fr; 1541 u_int32_t wsizeb; /* Constant: bits of window size. */ 1542 int frlast; /* Constant: last frame. */ 1543 1544 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1545 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1546 1547 replay = sav->replay; 1548 1549 if (replay->wsize == 0) 1550 return (1); /* No need to check replay. */ 1551 1552 /* Constant. */ 1553 frlast = replay->wsize - 1; 1554 wsizeb = replay->wsize << 3; 1555 1556 /* Sequence number of 0 is invalid. */ 1557 if (seq == 0) 1558 return (0); 1559 1560 /* First time is always okay. */ 1561 if (replay->count == 0) 1562 return (1); 1563 1564 if (seq > replay->lastseq) { 1565 /* Larger sequences are okay. */ 1566 return (1); 1567 } else { 1568 /* seq is equal or less than lastseq. */ 1569 diff = replay->lastseq - seq; 1570 1571 /* Over range to check, i.e. too old or wrapped. */ 1572 if (diff >= wsizeb) 1573 return (0); 1574 1575 fr = frlast - diff / 8; 1576 1577 /* This packet already seen? */ 1578 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1579 return (0); 1580 1581 /* Out of order but good. */ 1582 return (1); 1583 } 1584 } 1585 1586 /* 1587 * Check replay counter whether to update or not. 1588 * OUT: 0: OK 1589 * 1: NG 1590 */ 1591 int 1592 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav) 1593 { 1594 INIT_VNET_IPSEC(curvnet); 1595 struct secreplay *replay; 1596 u_int32_t diff; 1597 int fr; 1598 u_int32_t wsizeb; /* Constant: bits of window size. */ 1599 int frlast; /* Constant: last frame. */ 1600 1601 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1602 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1603 1604 replay = sav->replay; 1605 1606 if (replay->wsize == 0) 1607 goto ok; /* No need to check replay. */ 1608 1609 /* Constant. */ 1610 frlast = replay->wsize - 1; 1611 wsizeb = replay->wsize << 3; 1612 1613 /* Sequence number of 0 is invalid. */ 1614 if (seq == 0) 1615 return (1); 1616 1617 /* First time. */ 1618 if (replay->count == 0) { 1619 replay->lastseq = seq; 1620 bzero(replay->bitmap, replay->wsize); 1621 (replay->bitmap)[frlast] = 1; 1622 goto ok; 1623 } 1624 1625 if (seq > replay->lastseq) { 1626 /* seq is larger than lastseq. */ 1627 diff = seq - replay->lastseq; 1628 1629 /* New larger sequence number. */ 1630 if (diff < wsizeb) { 1631 /* In window. */ 1632 /* Set bit for this packet. */ 1633 vshiftl(replay->bitmap, diff, replay->wsize); 1634 (replay->bitmap)[frlast] |= 1; 1635 } else { 1636 /* This packet has a "way larger". */ 1637 bzero(replay->bitmap, replay->wsize); 1638 (replay->bitmap)[frlast] = 1; 1639 } 1640 replay->lastseq = seq; 1641 1642 /* Larger is good. */ 1643 } else { 1644 /* seq is equal or less than lastseq. */ 1645 diff = replay->lastseq - seq; 1646 1647 /* Over range to check, i.e. too old or wrapped. */ 1648 if (diff >= wsizeb) 1649 return (1); 1650 1651 fr = frlast - diff / 8; 1652 1653 /* This packet already seen? */ 1654 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1655 return (1); 1656 1657 /* Mark as seen. */ 1658 (replay->bitmap)[fr] |= (1 << (diff % 8)); 1659 1660 /* Out of order but good. */ 1661 } 1662 1663 ok: 1664 if (replay->count == ~0) { 1665 1666 /* Set overflow flag. */ 1667 replay->overflow++; 1668 1669 /* Don't increment, no more packets accepted. */ 1670 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 1671 return (1); 1672 1673 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1674 __func__, replay->overflow, ipsec_logsastr(sav))); 1675 } 1676 1677 replay->count++; 1678 1679 return (0); 1680 } 1681 1682 /* 1683 * Shift variable length buffer to left. 1684 * IN: bitmap: pointer to the buffer 1685 * nbit: the number of to shift. 1686 * wsize: buffer size (bytes). 1687 */ 1688 static void 1689 vshiftl(unsigned char *bitmap, int nbit, int wsize) 1690 { 1691 int s, j, i; 1692 unsigned char over; 1693 1694 for (j = 0; j < nbit; j += 8) { 1695 s = (nbit - j < 8) ? (nbit - j): 8; 1696 bitmap[0] <<= s; 1697 for (i = 1; i < wsize; i++) { 1698 over = (bitmap[i] >> (8 - s)); 1699 bitmap[i] <<= s; 1700 bitmap[i-1] |= over; 1701 } 1702 } 1703 } 1704 1705 #ifdef INET 1706 /* Return a printable string for the IPv4 address. */ 1707 static char * 1708 inet_ntoa4(struct in_addr ina) 1709 { 1710 static char buf[4][4 * sizeof "123" + 4]; 1711 unsigned char *ucp = (unsigned char *) &ina; 1712 static int i = 3; 1713 1714 /* XXX-BZ Returns static buffer. */ 1715 i = (i + 1) % 4; 1716 sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff, 1717 ucp[2] & 0xff, ucp[3] & 0xff); 1718 return (buf[i]); 1719 } 1720 #endif 1721 1722 /* Return a printable string for the address. */ 1723 char * 1724 ipsec_address(union sockaddr_union* sa) 1725 { 1726 #ifdef INET6 1727 char ip6buf[INET6_ADDRSTRLEN]; 1728 #endif 1729 1730 switch (sa->sa.sa_family) { 1731 #ifdef INET 1732 case AF_INET: 1733 return (inet_ntoa4(sa->sin.sin_addr)); 1734 #endif /* INET */ 1735 #ifdef INET6 1736 case AF_INET6: 1737 return (ip6_sprintf(ip6buf, &sa->sin6.sin6_addr)); 1738 #endif /* INET6 */ 1739 default: 1740 return ("(unknown address family)"); 1741 } 1742 } 1743 1744 const char * 1745 ipsec_logsastr(struct secasvar *sav) 1746 { 1747 static char buf[256]; 1748 char *p; 1749 struct secasindex *saidx = &sav->sah->saidx; 1750 1751 IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 1752 ("address family mismatch")); 1753 1754 p = buf; 1755 snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi)); 1756 while (p && *p) 1757 p++; 1758 /* NB: only use ipsec_address on one address at a time. */ 1759 snprintf(p, sizeof (buf) - (p - buf), "src=%s ", 1760 ipsec_address(&saidx->src)); 1761 while (p && *p) 1762 p++; 1763 snprintf(p, sizeof (buf) - (p - buf), "dst=%s)", 1764 ipsec_address(&saidx->dst)); 1765 1766 return (buf); 1767 } 1768 1769 void 1770 ipsec_dumpmbuf(struct mbuf *m) 1771 { 1772 int totlen; 1773 int i; 1774 u_char *p; 1775 1776 totlen = 0; 1777 printf("---\n"); 1778 while (m) { 1779 p = mtod(m, u_char *); 1780 for (i = 0; i < m->m_len; i++) { 1781 printf("%02x ", p[i]); 1782 totlen++; 1783 if (totlen % 16 == 0) 1784 printf("\n"); 1785 } 1786 m = m->m_next; 1787 } 1788 if (totlen % 16 != 0) 1789 printf("\n"); 1790 printf("---\n"); 1791 } 1792 1793 static void 1794 ipsec_attach(void) 1795 { 1796 1797 #ifndef VIMAGE_GLOBALS 1798 vnet_mod_register(&vnet_ipsec_modinfo); 1799 #else 1800 ipsec_iattach(NULL); 1801 #endif 1802 } 1803 1804 static int 1805 ipsec_iattach(const void *unused __unused) 1806 { 1807 INIT_VNET_IPSEC(curvnet); 1808 1809 SECPOLICY_LOCK_INIT(&V_ip4_def_policy); 1810 V_ip4_def_policy.refcnt = 1; /* NB: disallow free. */ 1811 1812 return (0); 1813 } 1814 1815 #ifdef VIMAGE 1816 static int 1817 ipsec_idetach(const void *unused __unused) 1818 { 1819 1820 /* XXX revisit this! */ 1821 1822 return (0); 1823 } 1824 #endif 1825 SYSINIT(ipsec, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST, ipsec_attach, NULL); 1826 1827 1828 /* XXX This stuff doesn't belong here... */ 1829 1830 static struct xformsw* xforms = NULL; 1831 1832 /* 1833 * Register a transform; typically at system startup. 1834 */ 1835 void 1836 xform_register(struct xformsw* xsp) 1837 { 1838 1839 xsp->xf_next = xforms; 1840 xforms = xsp; 1841 } 1842 1843 /* 1844 * Initialize transform support in an sav. 1845 */ 1846 int 1847 xform_init(struct secasvar *sav, int xftype) 1848 { 1849 struct xformsw *xsp; 1850 1851 if (sav->tdb_xform != NULL) /* Previously initialized. */ 1852 return (0); 1853 for (xsp = xforms; xsp; xsp = xsp->xf_next) 1854 if (xsp->xf_type == xftype) 1855 return ((*xsp->xf_init)(sav, xsp)); 1856 return (EINVAL); 1857 } 1858