ipsec.c revision 253088
1/* $FreeBSD: head/sys/netipsec/ipsec.c 253088 2013-07-09 10:08:13Z ae $ */ 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 57#include <net/if.h> 58#include <net/route.h> 59#include <net/vnet.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#ifdef IPSEC_DEBUG 101VNET_DEFINE(int, ipsec_debug) = 1; 102#else 103VNET_DEFINE(int, ipsec_debug) = 0; 104#endif 105 106/* NB: name changed so netstat doesn't use it. */ 107VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec4stat); 108VNET_PCPUSTAT_SYSINIT(ipsec4stat); 109 110#ifdef VIMAGE 111VNET_PCPUSTAT_SYSUNINIT(ipsec4stat); 112#endif /* VIMAGE */ 113 114VNET_DEFINE(int, ip4_ah_offsetmask) = 0; /* maybe IP_DF? */ 115/* DF bit on encap. 0: clear 1: set 2: copy */ 116VNET_DEFINE(int, ip4_ipsec_dfbit) = 0; 117VNET_DEFINE(int, ip4_esp_trans_deflev) = IPSEC_LEVEL_USE; 118VNET_DEFINE(int, ip4_esp_net_deflev) = IPSEC_LEVEL_USE; 119VNET_DEFINE(int, ip4_ah_trans_deflev) = IPSEC_LEVEL_USE; 120VNET_DEFINE(int, ip4_ah_net_deflev) = IPSEC_LEVEL_USE; 121VNET_DEFINE(struct secpolicy, ip4_def_policy); 122/* ECN ignore(-1)/forbidden(0)/allowed(1) */ 123VNET_DEFINE(int, ip4_ipsec_ecn) = 0; 124VNET_DEFINE(int, ip4_esp_randpad) = -1; 125 126/* 127 * Crypto support requirements: 128 * 129 * 1 require hardware support 130 * -1 require software support 131 * 0 take anything 132 */ 133VNET_DEFINE(int, crypto_support) = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE; 134 135FEATURE(ipsec, "Internet Protocol Security (IPsec)"); 136#ifdef IPSEC_NAT_T 137FEATURE(ipsec_natt, "UDP Encapsulation of IPsec ESP Packets ('NAT-T')"); 138#endif 139 140SYSCTL_DECL(_net_inet_ipsec); 141 142/* net.inet.ipsec */ 143SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy, 144 CTLFLAG_RW, &VNET_NAME(ip4_def_policy).policy, 0, 145 "IPsec default policy."); 146SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev, 147 CTLFLAG_RW, &VNET_NAME(ip4_esp_trans_deflev), 0, 148 "Default ESP transport mode level"); 149SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev, 150 CTLFLAG_RW, &VNET_NAME(ip4_esp_net_deflev), 0, 151 "Default ESP tunnel mode level."); 152SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev, 153 CTLFLAG_RW, &VNET_NAME(ip4_ah_trans_deflev), 0, 154 "AH transfer mode default level."); 155SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev, 156 CTLFLAG_RW, &VNET_NAME(ip4_ah_net_deflev), 0, 157 "AH tunnel mode default level."); 158SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos, 159 CTLFLAG_RW, &VNET_NAME(ah_cleartos), 0, 160 "If set clear type-of-service field when doing AH computation."); 161SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, ah_offsetmask, 162 CTLFLAG_RW, &VNET_NAME(ip4_ah_offsetmask), 0, 163 "If not set clear offset field mask when doing AH computation."); 164SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit, 165 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_dfbit), 0, 166 "Do not fragment bit on encap."); 167SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn, 168 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_ecn), 0, 169 "Explicit Congestion Notification handling."); 170SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEBUG, debug, 171 CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0, 172 "Enable IPsec debugging output when set."); 173SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, crypto_support, 174 CTLFLAG_RW, &VNET_NAME(crypto_support), 0, 175 "Crypto driver selection."); 176SYSCTL_VNET_PCPUSTAT(_net_inet_ipsec, OID_AUTO, ipsecstats, struct ipsecstat, 177 ipsec4stat, "IPsec IPv4 statistics."); 178 179#ifdef REGRESSION 180/* 181 * When set to 1, IPsec will send packets with the same sequence number. 182 * This allows to verify if the other side has proper replay attacks detection. 183 */ 184VNET_DEFINE(int, ipsec_replay) = 0; 185SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_replay, 186 CTLFLAG_RW, &VNET_NAME(ipsec_replay), 0, 187 "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 */ 192VNET_DEFINE(int, ipsec_integrity) = 0; 193SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_integrity, 194 CTLFLAG_RW, &VNET_NAME(ipsec_integrity), 0, 195 "Emulate man-in-the-middle attack"); 196#endif 197 198#ifdef INET6 199VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec6stat); 200VNET_PCPUSTAT_SYSINIT(ipsec6stat); 201 202#ifdef VIMAGE 203VNET_PCPUSTAT_SYSUNINIT(ipsec6stat); 204#endif /* VIMAGE */ 205 206VNET_DEFINE(int, ip6_esp_trans_deflev) = IPSEC_LEVEL_USE; 207VNET_DEFINE(int, ip6_esp_net_deflev) = IPSEC_LEVEL_USE; 208VNET_DEFINE(int, ip6_ah_trans_deflev) = IPSEC_LEVEL_USE; 209VNET_DEFINE(int, ip6_ah_net_deflev) = IPSEC_LEVEL_USE; 210VNET_DEFINE(int, ip6_ipsec_ecn) = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 211 212SYSCTL_DECL(_net_inet6_ipsec6); 213 214/* net.inet6.ipsec6 */ 215SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy, CTLFLAG_RW, 216 &VNET_NAME(ip4_def_policy).policy, 0, 217 "IPsec default policy."); 218SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV, 219 esp_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_trans_deflev), 0, 220 "Default ESP transport mode level."); 221SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV, 222 esp_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_net_deflev), 0, 223 "Default ESP tunnel mode level."); 224SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV, 225 ah_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_trans_deflev), 0, 226 "AH transfer mode default level."); 227SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV, 228 ah_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_net_deflev), 0, 229 "AH tunnel mode default level."); 230SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_ECN, 231 ecn, CTLFLAG_RW, &VNET_NAME(ip6_ipsec_ecn), 0, 232 "Explicit Congestion Notification handling."); 233SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEBUG, debug, CTLFLAG_RW, 234 &VNET_NAME(ipsec_debug), 0, 235 "Enable IPsec debugging output when set."); 236SYSCTL_VNET_PCPUSTAT(_net_inet6_ipsec6, IPSECCTL_STATS, ipsecstats, 237 struct ipsecstat, ipsec6stat, "IPsec IPv6 statistics."); 238#endif /* INET6 */ 239 240static int ipsec_setspidx_inpcb __P((struct mbuf *, struct inpcb *)); 241static int ipsec_setspidx __P((struct mbuf *, struct secpolicyindex *, int)); 242static void ipsec4_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 243static int ipsec4_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 244#ifdef INET6 245static void ipsec6_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 246static int ipsec6_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 247#endif 248static void ipsec_delpcbpolicy __P((struct inpcbpolicy *)); 249static struct secpolicy *ipsec_deepcopy_policy __P((struct secpolicy *src)); 250static void vshiftl __P((unsigned char *, int, int)); 251 252MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy"); 253 254/* 255 * Return a held reference to the default SP. 256 */ 257static struct secpolicy * 258key_allocsp_default(const char* where, int tag) 259{ 260 struct secpolicy *sp; 261 262 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 263 printf("DP key_allocsp_default from %s:%u\n", where, tag)); 264 265 sp = &V_ip4_def_policy; 266 if (sp->policy != IPSEC_POLICY_DISCARD && 267 sp->policy != IPSEC_POLICY_NONE) { 268 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n", 269 sp->policy, IPSEC_POLICY_NONE)); 270 sp->policy = IPSEC_POLICY_NONE; 271 } 272 key_addref(sp); 273 274 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 275 printf("DP key_allocsp_default returns SP:%p (%u)\n", 276 sp, sp->refcnt)); 277 return (sp); 278} 279#define KEY_ALLOCSP_DEFAULT() \ 280 key_allocsp_default(__FILE__, __LINE__) 281 282/* 283 * For OUTBOUND packet having a socket. Searching SPD for packet, 284 * and return a pointer to SP. 285 * OUT: NULL: no apropreate SP found, the following value is set to error. 286 * 0 : bypass 287 * EACCES : discard packet. 288 * ENOENT : ipsec_acquire() in progress, maybe. 289 * others : error occured. 290 * others: a pointer to SP 291 * 292 * NOTE: IPv6 mapped adddress concern is implemented here. 293 */ 294struct secpolicy * 295ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir) 296{ 297 struct secpolicy *sp; 298 299 IPSEC_ASSERT(tdbi != NULL, ("null tdbi")); 300 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 301 ("invalid direction %u", dir)); 302 303 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir); 304 if (sp == NULL) /*XXX????*/ 305 sp = KEY_ALLOCSP_DEFAULT(); 306 IPSEC_ASSERT(sp != NULL, ("null SP")); 307 return (sp); 308} 309 310/* 311 * For OUTBOUND packet having a socket. Searching SPD for packet, 312 * and return a pointer to SP. 313 * OUT: NULL: no apropreate SP found, the following value is set to error. 314 * 0 : bypass 315 * EACCES : discard packet. 316 * ENOENT : ipsec_acquire() in progress, maybe. 317 * others : error occured. 318 * others: a pointer to SP 319 * 320 * NOTE: IPv6 mapped adddress concern is implemented here. 321 */ 322static struct secpolicy * 323ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb *inp, int *error) 324{ 325 struct inpcbpolicy *pcbsp; 326 struct secpolicy *currsp = NULL; /* Policy on socket. */ 327 struct secpolicy *sp; 328 329 IPSEC_ASSERT(m != NULL, ("null mbuf")); 330 IPSEC_ASSERT(inp != NULL, ("null inpcb")); 331 IPSEC_ASSERT(error != NULL, ("null error")); 332 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 333 ("invalid direction %u", dir)); 334 335 /* Set spidx in pcb. */ 336 *error = ipsec_setspidx_inpcb(m, inp); 337 if (*error) 338 return (NULL); 339 340 pcbsp = inp->inp_sp; 341 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp")); 342 switch (dir) { 343 case IPSEC_DIR_INBOUND: 344 currsp = pcbsp->sp_in; 345 break; 346 case IPSEC_DIR_OUTBOUND: 347 currsp = pcbsp->sp_out; 348 break; 349 } 350 IPSEC_ASSERT(currsp != NULL, ("null currsp")); 351 352 if (pcbsp->priv) { /* When privilieged socket. */ 353 switch (currsp->policy) { 354 case IPSEC_POLICY_BYPASS: 355 case IPSEC_POLICY_IPSEC: 356 key_addref(currsp); 357 sp = currsp; 358 break; 359 360 case IPSEC_POLICY_ENTRUST: 361 /* Look for a policy in SPD. */ 362 sp = KEY_ALLOCSP(&currsp->spidx, dir); 363 if (sp == NULL) /* No SP found. */ 364 sp = KEY_ALLOCSP_DEFAULT(); 365 break; 366 367 default: 368 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n", 369 __func__, currsp->policy)); 370 *error = EINVAL; 371 return (NULL); 372 } 373 } else { /* Unpriv, SPD has policy. */ 374 sp = KEY_ALLOCSP(&currsp->spidx, dir); 375 if (sp == NULL) { /* No SP found. */ 376 switch (currsp->policy) { 377 case IPSEC_POLICY_BYPASS: 378 ipseclog((LOG_ERR, "%s: Illegal policy for " 379 "non-priviliged defined %d\n", 380 __func__, currsp->policy)); 381 *error = EINVAL; 382 return (NULL); 383 384 case IPSEC_POLICY_ENTRUST: 385 sp = KEY_ALLOCSP_DEFAULT(); 386 break; 387 388 case IPSEC_POLICY_IPSEC: 389 key_addref(currsp); 390 sp = currsp; 391 break; 392 393 default: 394 ipseclog((LOG_ERR, "%s: Invalid policy for " 395 "PCB %d\n", __func__, currsp->policy)); 396 *error = EINVAL; 397 return (NULL); 398 } 399 } 400 } 401 IPSEC_ASSERT(sp != NULL, 402 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy)); 403 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 404 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n", 405 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt)); 406 return (sp); 407} 408 409/* 410 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 411 * and return a pointer to SP. 412 * OUT: positive: a pointer to the entry for security policy leaf matched. 413 * NULL: no apropreate SP found, the following value is set to error. 414 * 0 : bypass 415 * EACCES : discard packet. 416 * ENOENT : ipsec_acquire() in progress, maybe. 417 * others : error occured. 418 */ 419struct secpolicy * 420ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 421{ 422 struct secpolicyindex spidx; 423 struct secpolicy *sp; 424 425 IPSEC_ASSERT(m != NULL, ("null mbuf")); 426 IPSEC_ASSERT(error != NULL, ("null error")); 427 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 428 ("invalid direction %u", dir)); 429 430 sp = NULL; 431 if (key_havesp(dir)) { 432 /* Make an index to look for a policy. */ 433 *error = ipsec_setspidx(m, &spidx, 434 (flag & IP_FORWARDING) ? 0 : 1); 435 if (*error != 0) { 436 DPRINTF(("%s: setpidx failed, dir %u flag %u\n", 437 __func__, dir, flag)); 438 return (NULL); 439 } 440 spidx.dir = dir; 441 442 sp = KEY_ALLOCSP(&spidx, dir); 443 } 444 if (sp == NULL) /* No SP found, use system default. */ 445 sp = KEY_ALLOCSP_DEFAULT(); 446 IPSEC_ASSERT(sp != NULL, ("null SP")); 447 return (sp); 448} 449 450struct secpolicy * 451ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 452 struct inpcb *inp) 453{ 454 struct secpolicy *sp; 455 456 *error = 0; 457 if (inp == NULL) 458 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 459 else 460 sp = ipsec_getpolicybysock(m, dir, inp, error); 461 if (sp == NULL) { 462 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error")); 463 IPSECSTAT_INC(ips_out_inval); 464 return (NULL); 465 } 466 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error)); 467 switch (sp->policy) { 468 case IPSEC_POLICY_ENTRUST: 469 default: 470 printf("%s: invalid policy %u\n", __func__, sp->policy); 471 /* FALLTHROUGH */ 472 case IPSEC_POLICY_DISCARD: 473 IPSECSTAT_INC(ips_out_polvio); 474 *error = -EINVAL; /* Packet is discarded by caller. */ 475 break; 476 case IPSEC_POLICY_BYPASS: 477 case IPSEC_POLICY_NONE: 478 KEY_FREESP(&sp); 479 sp = NULL; /* NB: force NULL result. */ 480 break; 481 case IPSEC_POLICY_IPSEC: 482 if (sp->req == NULL) /* Acquire a SA. */ 483 *error = key_spdacquire(sp); 484 break; 485 } 486 if (*error != 0) { 487 KEY_FREESP(&sp); 488 sp = NULL; 489 } 490 return (sp); 491} 492 493static int 494ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp) 495{ 496 int error; 497 498 IPSEC_ASSERT(inp != NULL, ("null inp")); 499 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 500 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL, 501 ("null sp_in || sp_out")); 502 503 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1); 504 if (error == 0) { 505 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 506 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx; 507 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 508 } else { 509 bzero(&inp->inp_sp->sp_in->spidx, 510 sizeof (inp->inp_sp->sp_in->spidx)); 511 bzero(&inp->inp_sp->sp_out->spidx, 512 sizeof (inp->inp_sp->sp_in->spidx)); 513 } 514 return (error); 515} 516 517/* 518 * Configure security policy index (src/dst/proto/sport/dport) 519 * by looking at the content of mbuf. 520 * The caller is responsible for error recovery (like clearing up spidx). 521 */ 522static int 523ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 524{ 525 struct ip *ip = NULL; 526 struct ip ipbuf; 527 u_int v; 528 struct mbuf *n; 529 int len; 530 int error; 531 532 IPSEC_ASSERT(m != NULL, ("null mbuf")); 533 534 /* 535 * Validate m->m_pkthdr.len. We see incorrect length if we 536 * mistakenly call this function with inconsistent mbuf chain 537 * (like 4.4BSD tcp/udp processing). XXX Should we panic here? 538 */ 539 len = 0; 540 for (n = m; n; n = n->m_next) 541 len += n->m_len; 542 if (m->m_pkthdr.len != len) { 543 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 544 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n", 545 __func__, len, m->m_pkthdr.len)); 546 return (EINVAL); 547 } 548 549 if (m->m_pkthdr.len < sizeof(struct ip)) { 550 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 551 printf("%s: pkthdr len(%d) too small (v4), ignored.\n", 552 __func__, m->m_pkthdr.len)); 553 return (EINVAL); 554 } 555 556 if (m->m_len >= sizeof(*ip)) 557 ip = mtod(m, struct ip *); 558 else { 559 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf); 560 ip = &ipbuf; 561 } 562#ifdef _IP_VHL 563 v = _IP_VHL_V(ip->ip_vhl); 564#else 565 v = ip->ip_v; 566#endif 567 switch (v) { 568 case 4: 569 error = ipsec4_setspidx_ipaddr(m, spidx); 570 if (error) 571 return (error); 572 ipsec4_get_ulp(m, spidx, needport); 573 return (0); 574#ifdef INET6 575 case 6: 576 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 577 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 578 printf("%s: pkthdr len(%d) too small (v6), " 579 "ignored\n", __func__, m->m_pkthdr.len)); 580 return (EINVAL); 581 } 582 error = ipsec6_setspidx_ipaddr(m, spidx); 583 if (error) 584 return (error); 585 ipsec6_get_ulp(m, spidx, needport); 586 return (0); 587#endif 588 default: 589 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 590 printf("%s: " "unknown IP version %u, ignored.\n", 591 __func__, v)); 592 return (EINVAL); 593 } 594} 595 596static void 597ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 598{ 599 u_int8_t nxt; 600 int off; 601 602 /* Sanity check. */ 603 IPSEC_ASSERT(m != NULL, ("null mbuf")); 604 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short")); 605 606 if (m->m_len >= sizeof (struct ip)) { 607 struct ip *ip = mtod(m, struct ip *); 608 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 609 goto done; 610#ifdef _IP_VHL 611 off = _IP_VHL_HL(ip->ip_vhl) << 2; 612#else 613 off = ip->ip_hl << 2; 614#endif 615 nxt = ip->ip_p; 616 } else { 617 struct ip ih; 618 619 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih); 620 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 621 goto done; 622#ifdef _IP_VHL 623 off = _IP_VHL_HL(ih.ip_vhl) << 2; 624#else 625 off = ih.ip_hl << 2; 626#endif 627 nxt = ih.ip_p; 628 } 629 630 while (off < m->m_pkthdr.len) { 631 struct ip6_ext ip6e; 632 struct tcphdr th; 633 struct udphdr uh; 634 635 switch (nxt) { 636 case IPPROTO_TCP: 637 spidx->ul_proto = nxt; 638 if (!needport) 639 goto done_proto; 640 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 641 goto done; 642 m_copydata(m, off, sizeof (th), (caddr_t) &th); 643 spidx->src.sin.sin_port = th.th_sport; 644 spidx->dst.sin.sin_port = th.th_dport; 645 return; 646 case IPPROTO_UDP: 647 spidx->ul_proto = nxt; 648 if (!needport) 649 goto done_proto; 650 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 651 goto done; 652 m_copydata(m, off, sizeof (uh), (caddr_t) &uh); 653 spidx->src.sin.sin_port = uh.uh_sport; 654 spidx->dst.sin.sin_port = uh.uh_dport; 655 return; 656 case IPPROTO_AH: 657 if (off + sizeof(ip6e) > m->m_pkthdr.len) 658 goto done; 659 /* XXX Sigh, this works but is totally bogus. */ 660 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e); 661 off += (ip6e.ip6e_len + 2) << 2; 662 nxt = ip6e.ip6e_nxt; 663 break; 664 case IPPROTO_ICMP: 665 default: 666 /* XXX Intermediate headers??? */ 667 spidx->ul_proto = nxt; 668 goto done_proto; 669 } 670 } 671done: 672 spidx->ul_proto = IPSEC_ULPROTO_ANY; 673done_proto: 674 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 675 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 676} 677 678/* Assumes that m is sane. */ 679static int 680ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 681{ 682 static const struct sockaddr_in template = { 683 sizeof (struct sockaddr_in), 684 AF_INET, 685 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 686 }; 687 688 spidx->src.sin = template; 689 spidx->dst.sin = template; 690 691 if (m->m_len < sizeof (struct ip)) { 692 m_copydata(m, offsetof(struct ip, ip_src), 693 sizeof (struct in_addr), 694 (caddr_t) &spidx->src.sin.sin_addr); 695 m_copydata(m, offsetof(struct ip, ip_dst), 696 sizeof (struct in_addr), 697 (caddr_t) &spidx->dst.sin.sin_addr); 698 } else { 699 struct ip *ip = mtod(m, struct ip *); 700 spidx->src.sin.sin_addr = ip->ip_src; 701 spidx->dst.sin.sin_addr = ip->ip_dst; 702 } 703 704 spidx->prefs = sizeof(struct in_addr) << 3; 705 spidx->prefd = sizeof(struct in_addr) << 3; 706 707 return (0); 708} 709 710#ifdef INET6 711static void 712ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 713{ 714 int off, nxt; 715 struct tcphdr th; 716 struct udphdr uh; 717 struct icmp6_hdr ih; 718 719 /* Sanity check. */ 720 if (m == NULL) 721 panic("%s: NULL pointer was passed.\n", __func__); 722 723 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 724 printf("%s:\n", __func__); kdebug_mbuf(m)); 725 726 /* Set default. */ 727 spidx->ul_proto = IPSEC_ULPROTO_ANY; 728 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 729 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 730 731 nxt = -1; 732 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 733 if (off < 0 || m->m_pkthdr.len < off) 734 return; 735 736 switch (nxt) { 737 case IPPROTO_TCP: 738 spidx->ul_proto = nxt; 739 if (!needport) 740 break; 741 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 742 break; 743 m_copydata(m, off, sizeof(th), (caddr_t)&th); 744 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 745 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 746 break; 747 case IPPROTO_UDP: 748 spidx->ul_proto = nxt; 749 if (!needport) 750 break; 751 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 752 break; 753 m_copydata(m, off, sizeof(uh), (caddr_t)&uh); 754 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 755 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 756 break; 757 case IPPROTO_ICMPV6: 758 spidx->ul_proto = nxt; 759 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 760 break; 761 m_copydata(m, off, sizeof(ih), (caddr_t)&ih); 762 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 763 htons((uint16_t)ih.icmp6_type); 764 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 765 htons((uint16_t)ih.icmp6_code); 766 break; 767 default: 768 /* XXX Intermediate headers??? */ 769 spidx->ul_proto = nxt; 770 break; 771 } 772} 773 774/* Assumes that m is sane. */ 775static int 776ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 777{ 778 struct ip6_hdr *ip6 = NULL; 779 struct ip6_hdr ip6buf; 780 struct sockaddr_in6 *sin6; 781 782 if (m->m_len >= sizeof(*ip6)) 783 ip6 = mtod(m, struct ip6_hdr *); 784 else { 785 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf); 786 ip6 = &ip6buf; 787 } 788 789 sin6 = (struct sockaddr_in6 *)&spidx->src; 790 bzero(sin6, sizeof(*sin6)); 791 sin6->sin6_family = AF_INET6; 792 sin6->sin6_len = sizeof(struct sockaddr_in6); 793 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src)); 794 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 795 sin6->sin6_addr.s6_addr16[1] = 0; 796 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 797 } 798 spidx->prefs = sizeof(struct in6_addr) << 3; 799 800 sin6 = (struct sockaddr_in6 *)&spidx->dst; 801 bzero(sin6, sizeof(*sin6)); 802 sin6->sin6_family = AF_INET6; 803 sin6->sin6_len = sizeof(struct sockaddr_in6); 804 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst)); 805 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 806 sin6->sin6_addr.s6_addr16[1] = 0; 807 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 808 } 809 spidx->prefd = sizeof(struct in6_addr) << 3; 810 811 return (0); 812} 813#endif 814 815static void 816ipsec_delpcbpolicy(struct inpcbpolicy *p) 817{ 818 819 free(p, M_IPSEC_INPCB); 820} 821 822/* Initialize policy in PCB. */ 823int 824ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp) 825{ 826 struct inpcbpolicy *new; 827 828 /* Sanity check. */ 829 if (so == NULL || pcb_sp == NULL) 830 panic("%s: NULL pointer was passed.\n", __func__); 831 832 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy), 833 M_IPSEC_INPCB, M_NOWAIT|M_ZERO); 834 if (new == NULL) { 835 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 836 return (ENOBUFS); 837 } 838 839 new->priv = IPSEC_IS_PRIVILEGED_SO(so); 840 841 if ((new->sp_in = KEY_NEWSP()) == NULL) { 842 ipsec_delpcbpolicy(new); 843 return (ENOBUFS); 844 } 845 new->sp_in->state = IPSEC_SPSTATE_ALIVE; 846 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 847 848 if ((new->sp_out = KEY_NEWSP()) == NULL) { 849 KEY_FREESP(&new->sp_in); 850 ipsec_delpcbpolicy(new); 851 return (ENOBUFS); 852 } 853 new->sp_out->state = IPSEC_SPSTATE_ALIVE; 854 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 855 856 *pcb_sp = new; 857 858 return (0); 859} 860 861/* Copy old IPsec policy into new. */ 862int 863ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new) 864{ 865 struct secpolicy *sp; 866 867 sp = ipsec_deepcopy_policy(old->sp_in); 868 if (sp) { 869 KEY_FREESP(&new->sp_in); 870 new->sp_in = sp; 871 } else 872 return (ENOBUFS); 873 874 sp = ipsec_deepcopy_policy(old->sp_out); 875 if (sp) { 876 KEY_FREESP(&new->sp_out); 877 new->sp_out = sp; 878 } else 879 return (ENOBUFS); 880 881 new->priv = old->priv; 882 883 return (0); 884} 885 886struct ipsecrequest * 887ipsec_newisr(void) 888{ 889 struct ipsecrequest *p; 890 891 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO); 892 if (p != NULL) 893 IPSECREQUEST_LOCK_INIT(p); 894 return (p); 895} 896 897void 898ipsec_delisr(struct ipsecrequest *p) 899{ 900 901 IPSECREQUEST_LOCK_DESTROY(p); 902 free(p, M_IPSEC_SR); 903} 904 905/* Deep-copy a policy in PCB. */ 906static struct secpolicy * 907ipsec_deepcopy_policy(struct secpolicy *src) 908{ 909 struct ipsecrequest *newchain = NULL; 910 struct ipsecrequest *p; 911 struct ipsecrequest **q; 912 struct ipsecrequest *r; 913 struct secpolicy *dst; 914 915 if (src == NULL) 916 return (NULL); 917 dst = KEY_NEWSP(); 918 if (dst == NULL) 919 return (NULL); 920 921 /* 922 * Deep-copy IPsec request chain. This is required since struct 923 * ipsecrequest is not reference counted. 924 */ 925 q = &newchain; 926 for (p = src->req; p; p = p->next) { 927 *q = ipsec_newisr(); 928 if (*q == NULL) 929 goto fail; 930 (*q)->saidx.proto = p->saidx.proto; 931 (*q)->saidx.mode = p->saidx.mode; 932 (*q)->level = p->level; 933 (*q)->saidx.reqid = p->saidx.reqid; 934 935 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src)); 936 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst)); 937 938 (*q)->sp = dst; 939 940 q = &((*q)->next); 941 } 942 943 dst->req = newchain; 944 dst->state = src->state; 945 dst->policy = src->policy; 946 /* Do not touch the refcnt fields. */ 947 948 return (dst); 949 950fail: 951 for (p = newchain; p; p = r) { 952 r = p->next; 953 ipsec_delisr(p); 954 p = NULL; 955 } 956 return (NULL); 957} 958 959/* Set policy and IPsec request if present. */ 960static int 961ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname, 962 caddr_t request, size_t len, struct ucred *cred) 963{ 964 struct sadb_x_policy *xpl; 965 struct secpolicy *newsp = NULL; 966 int error; 967 968 /* Sanity check. */ 969 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL) 970 return (EINVAL); 971 if (len < sizeof(*xpl)) 972 return (EINVAL); 973 xpl = (struct sadb_x_policy *)request; 974 975 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 976 printf("%s: passed policy\n", __func__); 977 kdebug_sadb_x_policy((struct sadb_ext *)xpl)); 978 979 /* Check policy type. */ 980 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */ 981 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 982 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 983 return (EINVAL); 984 985 /* Check privileged socket. */ 986 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 987 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0); 988 if (error) 989 return (EACCES); 990 } 991 992 /* Allocating new SP entry. */ 993 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 994 return (error); 995 996 newsp->state = IPSEC_SPSTATE_ALIVE; 997 998 /* Clear old SP and set new SP. */ 999 KEY_FREESP(pcb_sp); 1000 *pcb_sp = newsp; 1001 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1002 printf("%s: new policy\n", __func__); 1003 kdebug_secpolicy(newsp)); 1004 1005 return (0); 1006} 1007 1008int 1009ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request, 1010 size_t len, struct ucred *cred) 1011{ 1012 struct sadb_x_policy *xpl; 1013 struct secpolicy **pcb_sp; 1014 1015 /* Sanity check. */ 1016 if (inp == NULL || request == NULL) 1017 return (EINVAL); 1018 if (len < sizeof(*xpl)) 1019 return (EINVAL); 1020 xpl = (struct sadb_x_policy *)request; 1021 1022 /* Select direction. */ 1023 switch (xpl->sadb_x_policy_dir) { 1024 case IPSEC_DIR_INBOUND: 1025 pcb_sp = &inp->inp_sp->sp_in; 1026 break; 1027 case IPSEC_DIR_OUTBOUND: 1028 pcb_sp = &inp->inp_sp->sp_out; 1029 break; 1030 default: 1031 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1032 xpl->sadb_x_policy_dir)); 1033 return (EINVAL); 1034 } 1035 1036 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred)); 1037} 1038 1039int 1040ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len, 1041 struct mbuf **mp) 1042{ 1043 struct sadb_x_policy *xpl; 1044 struct secpolicy *pcb_sp; 1045 1046 /* Sanity check. */ 1047 if (inp == NULL || request == NULL || mp == NULL) 1048 return (EINVAL); 1049 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 1050 if (len < sizeof(*xpl)) 1051 return (EINVAL); 1052 xpl = (struct sadb_x_policy *)request; 1053 1054 /* Select direction. */ 1055 switch (xpl->sadb_x_policy_dir) { 1056 case IPSEC_DIR_INBOUND: 1057 pcb_sp = inp->inp_sp->sp_in; 1058 break; 1059 case IPSEC_DIR_OUTBOUND: 1060 pcb_sp = inp->inp_sp->sp_out; 1061 break; 1062 default: 1063 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1064 xpl->sadb_x_policy_dir)); 1065 return (EINVAL); 1066 } 1067 1068 /* Sanity check. Should be an IPSEC_ASSERT. */ 1069 if (pcb_sp == NULL) 1070 return (EINVAL); 1071 1072 *mp = key_sp2msg(pcb_sp); 1073 if (!*mp) { 1074 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 1075 return (ENOBUFS); 1076 } 1077 1078 (*mp)->m_type = MT_DATA; 1079 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1080 printf("%s:\n", __func__); kdebug_mbuf(*mp)); 1081 1082 return (0); 1083} 1084 1085/* Delete policy in PCB. */ 1086int 1087ipsec_delete_pcbpolicy(struct inpcb *inp) 1088{ 1089 IPSEC_ASSERT(inp != NULL, ("null inp")); 1090 1091 if (inp->inp_sp == NULL) 1092 return (0); 1093 1094 if (inp->inp_sp->sp_in != NULL) 1095 KEY_FREESP(&inp->inp_sp->sp_in); 1096 1097 if (inp->inp_sp->sp_out != NULL) 1098 KEY_FREESP(&inp->inp_sp->sp_out); 1099 1100 ipsec_delpcbpolicy(inp->inp_sp); 1101 inp->inp_sp = NULL; 1102 1103 return (0); 1104} 1105 1106/* 1107 * Return current level. 1108 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1109 */ 1110u_int 1111ipsec_get_reqlevel(struct ipsecrequest *isr) 1112{ 1113 u_int level = 0; 1114 u_int esp_trans_deflev, esp_net_deflev; 1115 u_int ah_trans_deflev, ah_net_deflev; 1116 1117 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument")); 1118 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1119 ("af family mismatch, src %u, dst %u", 1120 isr->sp->spidx.src.sa.sa_family, 1121 isr->sp->spidx.dst.sa.sa_family)); 1122 1123/* XXX Note that we have ipseclog() expanded here - code sync issue. */ 1124#define IPSEC_CHECK_DEFAULT(lev) \ 1125 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1126 && (lev) != IPSEC_LEVEL_UNIQUE) \ 1127 ? (V_ipsec_debug \ 1128 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\ 1129 (lev), IPSEC_LEVEL_REQUIRE) \ 1130 : 0), \ 1131 (lev) = IPSEC_LEVEL_REQUIRE, \ 1132 (lev) \ 1133 : (lev)) 1134 1135 /* Set default level. */ 1136 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1137#ifdef INET 1138 case AF_INET: 1139 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev); 1140 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev); 1141 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev); 1142 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev); 1143 break; 1144#endif 1145#ifdef INET6 1146 case AF_INET6: 1147 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev); 1148 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev); 1149 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev); 1150 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev); 1151 break; 1152#endif /* INET6 */ 1153 default: 1154 panic("%s: unknown af %u", 1155 __func__, isr->sp->spidx.src.sa.sa_family); 1156 } 1157 1158#undef IPSEC_CHECK_DEFAULT 1159 1160 /* Set level. */ 1161 switch (isr->level) { 1162 case IPSEC_LEVEL_DEFAULT: 1163 switch (isr->saidx.proto) { 1164 case IPPROTO_ESP: 1165 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1166 level = esp_net_deflev; 1167 else 1168 level = esp_trans_deflev; 1169 break; 1170 case IPPROTO_AH: 1171 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1172 level = ah_net_deflev; 1173 else 1174 level = ah_trans_deflev; 1175 break; 1176 case IPPROTO_IPCOMP: 1177 /* 1178 * We don't really care, as IPcomp document says that 1179 * we shouldn't compress small packets. 1180 */ 1181 level = IPSEC_LEVEL_USE; 1182 break; 1183 default: 1184 panic("%s: Illegal protocol defined %u\n", __func__, 1185 isr->saidx.proto); 1186 } 1187 break; 1188 1189 case IPSEC_LEVEL_USE: 1190 case IPSEC_LEVEL_REQUIRE: 1191 level = isr->level; 1192 break; 1193 case IPSEC_LEVEL_UNIQUE: 1194 level = IPSEC_LEVEL_REQUIRE; 1195 break; 1196 1197 default: 1198 panic("%s: Illegal IPsec level %u\n", __func__, isr->level); 1199 } 1200 1201 return (level); 1202} 1203 1204/* 1205 * Check security policy requirements against the actual 1206 * packet contents. Return one if the packet should be 1207 * reject as "invalid"; otherwiser return zero to have the 1208 * packet treated as "valid". 1209 * 1210 * OUT: 1211 * 0: valid 1212 * 1: invalid 1213 */ 1214int 1215ipsec_in_reject(struct secpolicy *sp, struct mbuf *m) 1216{ 1217 struct ipsecrequest *isr; 1218 int need_auth; 1219 1220 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1221 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1222 1223 /* Check policy. */ 1224 switch (sp->policy) { 1225 case IPSEC_POLICY_DISCARD: 1226 return (1); 1227 case IPSEC_POLICY_BYPASS: 1228 case IPSEC_POLICY_NONE: 1229 return (0); 1230 } 1231 1232 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1233 ("invalid policy %u", sp->policy)); 1234 1235 /* XXX Should compare policy against IPsec header history. */ 1236 1237 need_auth = 0; 1238 for (isr = sp->req; isr != NULL; isr = isr->next) { 1239 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1240 continue; 1241 switch (isr->saidx.proto) { 1242 case IPPROTO_ESP: 1243 if ((m->m_flags & M_DECRYPTED) == 0) { 1244 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1245 printf("%s: ESP m_flags:%x\n", __func__, 1246 m->m_flags)); 1247 return (1); 1248 } 1249 1250 if (!need_auth && 1251 isr->sav != NULL && 1252 isr->sav->tdb_authalgxform != NULL && 1253 (m->m_flags & M_AUTHIPDGM) == 0) { 1254 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1255 printf("%s: ESP/AH m_flags:%x\n", __func__, 1256 m->m_flags)); 1257 return (1); 1258 } 1259 break; 1260 case IPPROTO_AH: 1261 need_auth = 1; 1262 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1263 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1264 printf("%s: AH m_flags:%x\n", __func__, 1265 m->m_flags)); 1266 return (1); 1267 } 1268 break; 1269 case IPPROTO_IPCOMP: 1270 /* 1271 * We don't really care, as IPcomp document 1272 * says that we shouldn't compress small 1273 * packets. IPComp policy should always be 1274 * treated as being in "use" level. 1275 */ 1276 break; 1277 } 1278 } 1279 return (0); /* Valid. */ 1280} 1281 1282static int 1283ipsec46_in_reject(struct mbuf *m, struct inpcb *inp) 1284{ 1285 struct secpolicy *sp; 1286 int error; 1287 int result; 1288 1289 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1290 1291 /* 1292 * Get SP for this packet. 1293 * When we are called from ip_forward(), we call 1294 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1295 */ 1296 if (inp == NULL) 1297 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1298 else 1299 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error); 1300 1301 if (sp != NULL) { 1302 result = ipsec_in_reject(sp, m); 1303 KEY_FREESP(&sp); 1304 } else { 1305 result = 0; /* XXX Should be panic? 1306 * -> No, there may be error. */ 1307 } 1308 return (result); 1309} 1310 1311/* 1312 * Check AH/ESP integrity. 1313 * This function is called from tcp_input(), udp_input(), 1314 * and {ah,esp}4_input for tunnel mode. 1315 */ 1316int 1317ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1318{ 1319 int result; 1320 1321 result = ipsec46_in_reject(m, inp); 1322 if (result) 1323 IPSECSTAT_INC(ips_in_polvio); 1324 1325 return (result); 1326} 1327 1328#ifdef INET6 1329/* 1330 * Check AH/ESP integrity. 1331 * This function is called from tcp6_input(), udp6_input(), 1332 * and {ah,esp}6_input for tunnel mode. 1333 */ 1334int 1335ipsec6_in_reject(struct mbuf *m, struct inpcb *inp) 1336{ 1337 int result; 1338 1339 result = ipsec46_in_reject(m, inp); 1340 if (result) 1341 IPSEC6STAT_INC(ips_in_polvio); 1342 1343 return (result); 1344} 1345#endif 1346 1347/* 1348 * Compute the byte size to be occupied by IPsec header. 1349 * In case it is tunnelled, it includes the size of outer IP header. 1350 * NOTE: SP passed is freed in this function. 1351 */ 1352static size_t 1353ipsec_hdrsiz_internal(struct secpolicy *sp) 1354{ 1355 struct ipsecrequest *isr; 1356 size_t size; 1357 1358 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1359 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1360 1361 switch (sp->policy) { 1362 case IPSEC_POLICY_DISCARD: 1363 case IPSEC_POLICY_BYPASS: 1364 case IPSEC_POLICY_NONE: 1365 return (0); 1366 } 1367 1368 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1369 ("invalid policy %u", sp->policy)); 1370 1371 size = 0; 1372 for (isr = sp->req; isr != NULL; isr = isr->next) { 1373 size_t clen = 0; 1374 1375 switch (isr->saidx.proto) { 1376 case IPPROTO_ESP: 1377 clen = esp_hdrsiz(isr->sav); 1378 break; 1379 case IPPROTO_AH: 1380 clen = ah_hdrsiz(isr->sav); 1381 break; 1382 case IPPROTO_IPCOMP: 1383 clen = sizeof(struct ipcomp); 1384 break; 1385 } 1386 1387 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1388 switch (isr->saidx.dst.sa.sa_family) { 1389 case AF_INET: 1390 clen += sizeof(struct ip); 1391 break; 1392#ifdef INET6 1393 case AF_INET6: 1394 clen += sizeof(struct ip6_hdr); 1395 break; 1396#endif 1397 default: 1398 ipseclog((LOG_ERR, "%s: unknown AF %d in " 1399 "IPsec tunnel SA\n", __func__, 1400 ((struct sockaddr *)&isr->saidx.dst)->sa_family)); 1401 break; 1402 } 1403 } 1404 size += clen; 1405 } 1406 1407 return (size); 1408} 1409 1410/* 1411 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(), 1412 * disabled ip6_ipsec_mtu() and ip6_forward(). 1413 */ 1414size_t 1415ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1416{ 1417 struct secpolicy *sp; 1418 int error; 1419 size_t size; 1420 1421 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1422 1423 /* Get SP for this packet. 1424 * When we are called from ip_forward(), we call 1425 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1426 */ 1427 if (inp == NULL) 1428 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1429 else 1430 sp = ipsec_getpolicybysock(m, dir, inp, &error); 1431 1432 if (sp != NULL) { 1433 size = ipsec_hdrsiz_internal(sp); 1434 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1435 printf("%s: size:%lu.\n", __func__, 1436 (unsigned long)size)); 1437 1438 KEY_FREESP(&sp); 1439 } else { 1440 size = 0; /* XXX Should be panic? 1441 * -> No, we are called w/o knowing if 1442 * IPsec processing is needed. */ 1443 } 1444 return (size); 1445} 1446 1447/* 1448 * Check the variable replay window. 1449 * ipsec_chkreplay() performs replay check before ICV verification. 1450 * ipsec_updatereplay() updates replay bitmap. This must be called after 1451 * ICV verification (it also performs replay check, which is usually done 1452 * beforehand). 1453 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1454 * 1455 * Based on RFC 2401. 1456 */ 1457int 1458ipsec_chkreplay(u_int32_t seq, struct secasvar *sav) 1459{ 1460 const struct secreplay *replay; 1461 u_int32_t diff; 1462 int fr; 1463 u_int32_t wsizeb; /* Constant: bits of window size. */ 1464 int frlast; /* Constant: last frame. */ 1465 1466 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1467 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1468 1469 replay = sav->replay; 1470 1471 if (replay->wsize == 0) 1472 return (1); /* No need to check replay. */ 1473 1474 /* Constant. */ 1475 frlast = replay->wsize - 1; 1476 wsizeb = replay->wsize << 3; 1477 1478 /* Sequence number of 0 is invalid. */ 1479 if (seq == 0) 1480 return (0); 1481 1482 /* First time is always okay. */ 1483 if (replay->count == 0) 1484 return (1); 1485 1486 if (seq > replay->lastseq) { 1487 /* Larger sequences are okay. */ 1488 return (1); 1489 } else { 1490 /* seq is equal or less than lastseq. */ 1491 diff = replay->lastseq - seq; 1492 1493 /* Over range to check, i.e. too old or wrapped. */ 1494 if (diff >= wsizeb) 1495 return (0); 1496 1497 fr = frlast - diff / 8; 1498 1499 /* This packet already seen? */ 1500 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1501 return (0); 1502 1503 /* Out of order but good. */ 1504 return (1); 1505 } 1506} 1507 1508/* 1509 * Check replay counter whether to update or not. 1510 * OUT: 0: OK 1511 * 1: NG 1512 */ 1513int 1514ipsec_updatereplay(u_int32_t seq, struct secasvar *sav) 1515{ 1516 struct secreplay *replay; 1517 u_int32_t diff; 1518 int fr; 1519 u_int32_t wsizeb; /* Constant: bits of window size. */ 1520 int frlast; /* Constant: last frame. */ 1521 1522 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1523 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1524 1525 replay = sav->replay; 1526 1527 if (replay->wsize == 0) 1528 goto ok; /* No need to check replay. */ 1529 1530 /* Constant. */ 1531 frlast = replay->wsize - 1; 1532 wsizeb = replay->wsize << 3; 1533 1534 /* Sequence number of 0 is invalid. */ 1535 if (seq == 0) 1536 return (1); 1537 1538 /* First time. */ 1539 if (replay->count == 0) { 1540 replay->lastseq = seq; 1541 bzero(replay->bitmap, replay->wsize); 1542 (replay->bitmap)[frlast] = 1; 1543 goto ok; 1544 } 1545 1546 if (seq > replay->lastseq) { 1547 /* seq is larger than lastseq. */ 1548 diff = seq - replay->lastseq; 1549 1550 /* New larger sequence number. */ 1551 if (diff < wsizeb) { 1552 /* In window. */ 1553 /* Set bit for this packet. */ 1554 vshiftl(replay->bitmap, diff, replay->wsize); 1555 (replay->bitmap)[frlast] |= 1; 1556 } else { 1557 /* This packet has a "way larger". */ 1558 bzero(replay->bitmap, replay->wsize); 1559 (replay->bitmap)[frlast] = 1; 1560 } 1561 replay->lastseq = seq; 1562 1563 /* Larger is good. */ 1564 } else { 1565 /* seq is equal or less than lastseq. */ 1566 diff = replay->lastseq - seq; 1567 1568 /* Over range to check, i.e. too old or wrapped. */ 1569 if (diff >= wsizeb) 1570 return (1); 1571 1572 fr = frlast - diff / 8; 1573 1574 /* This packet already seen? */ 1575 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1576 return (1); 1577 1578 /* Mark as seen. */ 1579 (replay->bitmap)[fr] |= (1 << (diff % 8)); 1580 1581 /* Out of order but good. */ 1582 } 1583 1584ok: 1585 if (replay->count == ~0) { 1586 1587 /* Set overflow flag. */ 1588 replay->overflow++; 1589 1590 /* Don't increment, no more packets accepted. */ 1591 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 1592 return (1); 1593 1594 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1595 __func__, replay->overflow, ipsec_logsastr(sav))); 1596 } 1597 1598 replay->count++; 1599 1600 return (0); 1601} 1602 1603/* 1604 * Shift variable length buffer to left. 1605 * IN: bitmap: pointer to the buffer 1606 * nbit: the number of to shift. 1607 * wsize: buffer size (bytes). 1608 */ 1609static void 1610vshiftl(unsigned char *bitmap, int nbit, int wsize) 1611{ 1612 int s, j, i; 1613 unsigned char over; 1614 1615 for (j = 0; j < nbit; j += 8) { 1616 s = (nbit - j < 8) ? (nbit - j): 8; 1617 bitmap[0] <<= s; 1618 for (i = 1; i < wsize; i++) { 1619 over = (bitmap[i] >> (8 - s)); 1620 bitmap[i] <<= s; 1621 bitmap[i-1] |= over; 1622 } 1623 } 1624} 1625 1626#ifdef INET 1627/* Return a printable string for the IPv4 address. */ 1628static char * 1629inet_ntoa4(struct in_addr ina) 1630{ 1631 static char buf[4][4 * sizeof "123" + 4]; 1632 unsigned char *ucp = (unsigned char *) &ina; 1633 static int i = 3; 1634 1635 /* XXX-BZ Returns static buffer. */ 1636 i = (i + 1) % 4; 1637 sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff, 1638 ucp[2] & 0xff, ucp[3] & 0xff); 1639 return (buf[i]); 1640} 1641#endif 1642 1643/* Return a printable string for the address. */ 1644char * 1645ipsec_address(union sockaddr_union* sa) 1646{ 1647#ifdef INET6 1648 char ip6buf[INET6_ADDRSTRLEN]; 1649#endif 1650 1651 switch (sa->sa.sa_family) { 1652#ifdef INET 1653 case AF_INET: 1654 return (inet_ntoa4(sa->sin.sin_addr)); 1655#endif /* INET */ 1656#ifdef INET6 1657 case AF_INET6: 1658 return (ip6_sprintf(ip6buf, &sa->sin6.sin6_addr)); 1659#endif /* INET6 */ 1660 default: 1661 return ("(unknown address family)"); 1662 } 1663} 1664 1665const char * 1666ipsec_logsastr(struct secasvar *sav) 1667{ 1668 static char buf[256]; 1669 char *p; 1670 struct secasindex *saidx = &sav->sah->saidx; 1671 1672 IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 1673 ("address family mismatch")); 1674 1675 p = buf; 1676 snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi)); 1677 while (p && *p) 1678 p++; 1679 /* NB: only use ipsec_address on one address at a time. */ 1680 snprintf(p, sizeof (buf) - (p - buf), "src=%s ", 1681 ipsec_address(&saidx->src)); 1682 while (p && *p) 1683 p++; 1684 snprintf(p, sizeof (buf) - (p - buf), "dst=%s)", 1685 ipsec_address(&saidx->dst)); 1686 1687 return (buf); 1688} 1689 1690void 1691ipsec_dumpmbuf(struct mbuf *m) 1692{ 1693 int totlen; 1694 int i; 1695 u_char *p; 1696 1697 totlen = 0; 1698 printf("---\n"); 1699 while (m) { 1700 p = mtod(m, u_char *); 1701 for (i = 0; i < m->m_len; i++) { 1702 printf("%02x ", p[i]); 1703 totlen++; 1704 if (totlen % 16 == 0) 1705 printf("\n"); 1706 } 1707 m = m->m_next; 1708 } 1709 if (totlen % 16 != 0) 1710 printf("\n"); 1711 printf("---\n"); 1712} 1713 1714static void 1715ipsec_init(const void *unused __unused) 1716{ 1717 1718 SECPOLICY_LOCK_INIT(&V_ip4_def_policy); 1719 V_ip4_def_policy.refcnt = 1; /* NB: disallow free. */ 1720} 1721VNET_SYSINIT(ipsec_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, ipsec_init, 1722 NULL); 1723 1724 1725/* XXX This stuff doesn't belong here... */ 1726 1727static struct xformsw* xforms = NULL; 1728 1729/* 1730 * Register a transform; typically at system startup. 1731 */ 1732void 1733xform_register(struct xformsw* xsp) 1734{ 1735 1736 xsp->xf_next = xforms; 1737 xforms = xsp; 1738} 1739 1740/* 1741 * Initialize transform support in an sav. 1742 */ 1743int 1744xform_init(struct secasvar *sav, int xftype) 1745{ 1746 struct xformsw *xsp; 1747 1748 if (sav->tdb_xform != NULL) /* Previously initialized. */ 1749 return (0); 1750 for (xsp = xforms; xsp; xsp = xsp->xf_next) 1751 if (xsp->xf_type == xftype) 1752 return ((*xsp->xf_init)(sav, xsp)); 1753 return (EINVAL); 1754} 1755