ipsec.c revision 195782
1/* $FreeBSD: head/sys/netipsec/ipsec.c 195782 2009-07-20 13:55:33Z rwatson $ */ 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#include <net/vnet.h> 61 62#include <netinet/in.h> 63#include <netinet/in_systm.h> 64#include <netinet/ip.h> 65#include <netinet/ip_var.h> 66#include <netinet/in_var.h> 67#include <netinet/udp.h> 68#include <netinet/udp_var.h> 69#include <netinet/tcp.h> 70#include <netinet/udp.h> 71 72#include <netinet/ip6.h> 73#ifdef INET6 74#include <netinet6/ip6_var.h> 75#endif 76#include <netinet/in_pcb.h> 77#ifdef INET6 78#include <netinet/icmp6.h> 79#endif 80 81#include <sys/types.h> 82#include <netipsec/ipsec.h> 83#ifdef INET6 84#include <netipsec/ipsec6.h> 85#endif 86#include <netipsec/ah_var.h> 87#include <netipsec/esp_var.h> 88#include <netipsec/ipcomp.h> /*XXX*/ 89#include <netipsec/ipcomp_var.h> 90 91#include <netipsec/key.h> 92#include <netipsec/keydb.h> 93#include <netipsec/key_debug.h> 94 95#include <netipsec/xform.h> 96 97#include <machine/in_cksum.h> 98 99#include <opencrypto/cryptodev.h> 100 101#ifdef IPSEC_DEBUG 102VNET_DEFINE(int, ipsec_debug) = 1; 103#else 104VNET_DEFINE(int, ipsec_debug) = 0; 105#endif 106/* NB: name changed so netstat doesn't use it. */ 107VNET_DEFINE(struct ipsecstat, ipsec4stat); 108VNET_DEFINE(int, ip4_ah_offsetmask) = 0; /* maybe IP_DF? */ 109/* DF bit on encap. 0: clear 1: set 2: copy */ 110VNET_DEFINE(int, ip4_ipsec_dfbit) = 0; 111VNET_DEFINE(int, ip4_esp_trans_deflev) = IPSEC_LEVEL_USE; 112VNET_DEFINE(int, ip4_esp_net_deflev) = IPSEC_LEVEL_USE; 113VNET_DEFINE(int, ip4_ah_trans_deflev) = IPSEC_LEVEL_USE; 114VNET_DEFINE(int, ip4_ah_net_deflev) = IPSEC_LEVEL_USE; 115VNET_DEFINE(struct secpolicy, ip4_def_policy); 116/* ECN ignore(-1)/forbidden(0)/allowed(1) */ 117VNET_DEFINE(int, ip4_ipsec_ecn) = 0; 118VNET_DEFINE(int, ip4_esp_randpad) = -1; 119 120/* 121 * Crypto support requirements: 122 * 123 * 1 require hardware support 124 * -1 require software support 125 * 0 take anything 126 */ 127VNET_DEFINE(int, crypto_support) = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE; 128 129SYSCTL_DECL(_net_inet_ipsec); 130 131/* net.inet.ipsec */ 132SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy, 133 CTLFLAG_RW, &VNET_NAME(ip4_def_policy).policy, 0, 134 "IPsec default policy."); 135SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev, 136 CTLFLAG_RW, &VNET_NAME(ip4_esp_trans_deflev), 0, 137 "Default ESP transport mode level"); 138SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev, 139 CTLFLAG_RW, &VNET_NAME(ip4_esp_net_deflev), 0, 140 "Default ESP tunnel mode level."); 141SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev, 142 CTLFLAG_RW, &VNET_NAME(ip4_ah_trans_deflev), 0, 143 "AH transfer mode default level."); 144SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev, 145 CTLFLAG_RW, &VNET_NAME(ip4_ah_net_deflev), 0, 146 "AH tunnel mode default level."); 147SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos, 148 CTLFLAG_RW, &VNET_NAME(ah_cleartos), 0, 149 "If set clear type-of-service field when doing AH computation."); 150SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, ah_offsetmask, 151 CTLFLAG_RW, &VNET_NAME(ip4_ah_offsetmask), 0, 152 "If not set clear offset field mask when doing AH computation."); 153SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit, 154 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_dfbit), 0, 155 "Do not fragment bit on encap."); 156SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn, 157 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_ecn), 0, 158 "Explicit Congestion Notification handling."); 159SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEBUG, debug, 160 CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0, 161 "Enable IPsec debugging output when set."); 162SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, crypto_support, 163 CTLFLAG_RW, &VNET_NAME(crypto_support), 0, 164 "Crypto driver selection."); 165SYSCTL_VNET_STRUCT(_net_inet_ipsec, OID_AUTO, ipsecstats, 166 CTLFLAG_RD, &VNET_NAME(ipsec4stat), ipsecstat, 167 "IPsec IPv4 statistics."); 168 169#ifdef REGRESSION 170/* 171 * When set to 1, IPsec will send packets with the same sequence number. 172 * This allows to verify if the other side has proper replay attacks detection. 173 */ 174VNET_DEFINE(int, ipsec_replay) = 0; 175SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_replay, 176 CTLFLAG_RW, &VNET_NAME(ipsec_replay), 0, 177 "Emulate replay attack"); 178/* 179 * When set 1, IPsec will send packets with corrupted HMAC. 180 * This allows to verify if the other side properly detects modified packets. 181 */ 182VNET_DEFINE(int, ipsec_integrity) = 0; 183SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_integrity, 184 CTLFLAG_RW, &VNET_NAME(ipsec_integrity), 0, 185 "Emulate man-in-the-middle attack"); 186#endif 187 188#ifdef INET6 189VNET_DEFINE(struct ipsecstat, ipsec6stat); 190VNET_DEFINE(int, ip6_esp_trans_deflev) = IPSEC_LEVEL_USE; 191VNET_DEFINE(int, ip6_esp_net_deflev) = IPSEC_LEVEL_USE; 192VNET_DEFINE(int, ip6_ah_trans_deflev) = IPSEC_LEVEL_USE; 193VNET_DEFINE(int, ip6_ah_net_deflev) = IPSEC_LEVEL_USE; 194VNET_DEFINE(int, ip6_ipsec_ecn) = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 195 196SYSCTL_DECL(_net_inet6_ipsec6); 197 198/* net.inet6.ipsec6 */ 199#ifdef COMPAT_KAME 200SYSCTL_OID(_net_inet6_ipsec6, IPSECCTL_STATS, stats, CTLFLAG_RD, 201 0, 0, compat_ipsecstats_sysctl, "S", "IPsec IPv6 statistics."); 202#endif /* COMPAT_KAME */ 203SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy, CTLFLAG_RW, 204 &VNET_NAME(ip4_def_policy).policy, 0, 205 "IPsec default policy."); 206SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV, 207 esp_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_trans_deflev), 0, 208 "Default ESP transport mode level."); 209SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV, 210 esp_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_net_deflev), 0, 211 "Default ESP tunnel mode level."); 212SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV, 213 ah_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_trans_deflev), 0, 214 "AH transfer mode default level."); 215SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV, 216 ah_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_net_deflev), 0, 217 "AH tunnel mode default level."); 218SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_ECN, 219 ecn, CTLFLAG_RW, &VNET_NAME(ip6_ipsec_ecn), 0, 220 "Explicit Congestion Notification handling."); 221SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEBUG, debug, CTLFLAG_RW, 222 &VNET_NAME(ipsec_debug), 0, 223 "Enable IPsec debugging output when set."); 224SYSCTL_VNET_STRUCT(_net_inet6_ipsec6, IPSECCTL_STATS, 225 ipsecstats, CTLFLAG_RD, &VNET_NAME(ipsec6stat), ipsecstat, 226 "IPsec IPv6 statistics."); 227#endif /* INET6 */ 228 229static int ipsec_setspidx_inpcb __P((struct mbuf *, struct inpcb *)); 230static int ipsec_setspidx __P((struct mbuf *, struct secpolicyindex *, int)); 231static void ipsec4_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 232static int ipsec4_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 233#ifdef INET6 234static void ipsec6_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 235static int ipsec6_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 236#endif 237static void ipsec_delpcbpolicy __P((struct inpcbpolicy *)); 238static struct secpolicy *ipsec_deepcopy_policy __P((struct secpolicy *src)); 239static void vshiftl __P((unsigned char *, int, int)); 240 241MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy"); 242 243static int ipsec_iattach(const void *); 244#ifdef VIMAGE 245static const vnet_modinfo_t vnet_ipsec_modinfo = { 246 .vmi_id = VNET_MOD_IPSEC, 247 .vmi_name = "ipsec", 248 .vmi_iattach = ipsec_iattach, 249}; 250#endif 251 252/* 253 * Return a held reference to the default SP. 254 */ 255static struct secpolicy * 256key_allocsp_default(const char* where, int tag) 257{ 258 struct secpolicy *sp; 259 260 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 261 printf("DP key_allocsp_default from %s:%u\n", where, tag)); 262 263 sp = &V_ip4_def_policy; 264 if (sp->policy != IPSEC_POLICY_DISCARD && 265 sp->policy != IPSEC_POLICY_NONE) { 266 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n", 267 sp->policy, IPSEC_POLICY_NONE)); 268 sp->policy = IPSEC_POLICY_NONE; 269 } 270 key_addref(sp); 271 272 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 273 printf("DP key_allocsp_default returns SP:%p (%u)\n", 274 sp, sp->refcnt)); 275 return (sp); 276} 277#define KEY_ALLOCSP_DEFAULT() \ 278 key_allocsp_default(__FILE__, __LINE__) 279 280/* 281 * For OUTBOUND packet having a socket. Searching SPD for packet, 282 * and return a pointer to SP. 283 * OUT: NULL: no apropreate SP found, the following value is set to error. 284 * 0 : bypass 285 * EACCES : discard packet. 286 * ENOENT : ipsec_acquire() in progress, maybe. 287 * others : error occured. 288 * others: a pointer to SP 289 * 290 * NOTE: IPv6 mapped adddress concern is implemented here. 291 */ 292struct secpolicy * 293ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir) 294{ 295 struct secpolicy *sp; 296 297 IPSEC_ASSERT(tdbi != NULL, ("null tdbi")); 298 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 299 ("invalid direction %u", dir)); 300 301 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir); 302 if (sp == NULL) /*XXX????*/ 303 sp = KEY_ALLOCSP_DEFAULT(); 304 IPSEC_ASSERT(sp != NULL, ("null SP")); 305 return (sp); 306} 307 308/* 309 * For OUTBOUND packet having a socket. Searching SPD for packet, 310 * and return a pointer to SP. 311 * OUT: NULL: no apropreate SP found, the following value is set to error. 312 * 0 : bypass 313 * EACCES : discard packet. 314 * ENOENT : ipsec_acquire() in progress, maybe. 315 * others : error occured. 316 * others: a pointer to SP 317 * 318 * NOTE: IPv6 mapped adddress concern is implemented here. 319 */ 320static struct secpolicy * 321ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb *inp, int *error) 322{ 323 struct inpcbpolicy *pcbsp; 324 struct secpolicy *currsp = NULL; /* Policy on socket. */ 325 struct secpolicy *sp; 326 327 IPSEC_ASSERT(m != NULL, ("null mbuf")); 328 IPSEC_ASSERT(inp != NULL, ("null inpcb")); 329 IPSEC_ASSERT(error != NULL, ("null error")); 330 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 331 ("invalid direction %u", dir)); 332 333 /* Set spidx in pcb. */ 334 *error = ipsec_setspidx_inpcb(m, inp); 335 if (*error) 336 return (NULL); 337 338 pcbsp = inp->inp_sp; 339 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp")); 340 switch (dir) { 341 case IPSEC_DIR_INBOUND: 342 currsp = pcbsp->sp_in; 343 break; 344 case IPSEC_DIR_OUTBOUND: 345 currsp = pcbsp->sp_out; 346 break; 347 } 348 IPSEC_ASSERT(currsp != NULL, ("null currsp")); 349 350 if (pcbsp->priv) { /* When privilieged socket. */ 351 switch (currsp->policy) { 352 case IPSEC_POLICY_BYPASS: 353 case IPSEC_POLICY_IPSEC: 354 key_addref(currsp); 355 sp = currsp; 356 break; 357 358 case IPSEC_POLICY_ENTRUST: 359 /* Look for a policy in SPD. */ 360 sp = KEY_ALLOCSP(&currsp->spidx, dir); 361 if (sp == NULL) /* No SP found. */ 362 sp = KEY_ALLOCSP_DEFAULT(); 363 break; 364 365 default: 366 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n", 367 __func__, currsp->policy)); 368 *error = EINVAL; 369 return (NULL); 370 } 371 } else { /* Unpriv, SPD has policy. */ 372 sp = KEY_ALLOCSP(&currsp->spidx, dir); 373 if (sp == NULL) { /* No SP found. */ 374 switch (currsp->policy) { 375 case IPSEC_POLICY_BYPASS: 376 ipseclog((LOG_ERR, "%s: Illegal policy for " 377 "non-priviliged defined %d\n", 378 __func__, currsp->policy)); 379 *error = EINVAL; 380 return (NULL); 381 382 case IPSEC_POLICY_ENTRUST: 383 sp = KEY_ALLOCSP_DEFAULT(); 384 break; 385 386 case IPSEC_POLICY_IPSEC: 387 key_addref(currsp); 388 sp = currsp; 389 break; 390 391 default: 392 ipseclog((LOG_ERR, "%s: Invalid policy for " 393 "PCB %d\n", __func__, currsp->policy)); 394 *error = EINVAL; 395 return (NULL); 396 } 397 } 398 } 399 IPSEC_ASSERT(sp != NULL, 400 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy)); 401 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 402 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n", 403 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt)); 404 return (sp); 405} 406 407/* 408 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 409 * and return a pointer to SP. 410 * OUT: positive: a pointer to the entry for security policy leaf matched. 411 * NULL: no apropreate SP found, the following value is set to error. 412 * 0 : bypass 413 * EACCES : discard packet. 414 * ENOENT : ipsec_acquire() in progress, maybe. 415 * others : error occured. 416 */ 417struct secpolicy * 418ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 419{ 420 struct secpolicyindex spidx; 421 struct secpolicy *sp; 422 423 IPSEC_ASSERT(m != NULL, ("null mbuf")); 424 IPSEC_ASSERT(error != NULL, ("null error")); 425 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 426 ("invalid direction %u", dir)); 427 428 sp = NULL; 429 if (key_havesp(dir)) { 430 /* Make an index to look for a policy. */ 431 *error = ipsec_setspidx(m, &spidx, 432 (flag & IP_FORWARDING) ? 0 : 1); 433 if (*error != 0) { 434 DPRINTF(("%s: setpidx failed, dir %u flag %u\n", 435 __func__, dir, flag)); 436 return (NULL); 437 } 438 spidx.dir = dir; 439 440 sp = KEY_ALLOCSP(&spidx, dir); 441 } 442 if (sp == NULL) /* No SP found, use system default. */ 443 sp = KEY_ALLOCSP_DEFAULT(); 444 IPSEC_ASSERT(sp != NULL, ("null SP")); 445 return (sp); 446} 447 448struct secpolicy * 449ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 450 struct inpcb *inp) 451{ 452 struct secpolicy *sp; 453 454 *error = 0; 455 if (inp == NULL) 456 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 457 else 458 sp = ipsec_getpolicybysock(m, dir, inp, error); 459 if (sp == NULL) { 460 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error")); 461 V_ipsec4stat.ips_out_inval++; 462 return (NULL); 463 } 464 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error)); 465 switch (sp->policy) { 466 case IPSEC_POLICY_ENTRUST: 467 default: 468 printf("%s: invalid policy %u\n", __func__, sp->policy); 469 /* FALLTHROUGH */ 470 case IPSEC_POLICY_DISCARD: 471 V_ipsec4stat.ips_out_polvio++; 472 *error = -EINVAL; /* Packet is discarded by caller. */ 473 break; 474 case IPSEC_POLICY_BYPASS: 475 case IPSEC_POLICY_NONE: 476 KEY_FREESP(&sp); 477 sp = NULL; /* NB: force NULL result. */ 478 break; 479 case IPSEC_POLICY_IPSEC: 480 if (sp->req == NULL) /* Acquire a SA. */ 481 *error = key_spdacquire(sp); 482 break; 483 } 484 if (*error != 0) { 485 KEY_FREESP(&sp); 486 sp = NULL; 487 } 488 return (sp); 489} 490 491static int 492ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp) 493{ 494 int error; 495 496 IPSEC_ASSERT(inp != NULL, ("null inp")); 497 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 498 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL, 499 ("null sp_in || sp_out")); 500 501 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1); 502 if (error == 0) { 503 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 504 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx; 505 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 506 } else { 507 bzero(&inp->inp_sp->sp_in->spidx, 508 sizeof (inp->inp_sp->sp_in->spidx)); 509 bzero(&inp->inp_sp->sp_out->spidx, 510 sizeof (inp->inp_sp->sp_in->spidx)); 511 } 512 return (error); 513} 514 515/* 516 * Configure security policy index (src/dst/proto/sport/dport) 517 * by looking at the content of mbuf. 518 * The caller is responsible for error recovery (like clearing up spidx). 519 */ 520static int 521ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 522{ 523 struct ip *ip = NULL; 524 struct ip ipbuf; 525 u_int v; 526 struct mbuf *n; 527 int len; 528 int error; 529 530 IPSEC_ASSERT(m != NULL, ("null mbuf")); 531 532 /* 533 * Validate m->m_pkthdr.len. We see incorrect length if we 534 * mistakenly call this function with inconsistent mbuf chain 535 * (like 4.4BSD tcp/udp processing). XXX Should we panic here? 536 */ 537 len = 0; 538 for (n = m; n; n = n->m_next) 539 len += n->m_len; 540 if (m->m_pkthdr.len != len) { 541 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 542 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n", 543 __func__, len, m->m_pkthdr.len)); 544 return (EINVAL); 545 } 546 547 if (m->m_pkthdr.len < sizeof(struct ip)) { 548 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 549 printf("%s: pkthdr len(%d) too small (v4), ignored.\n", 550 __func__, m->m_pkthdr.len)); 551 return (EINVAL); 552 } 553 554 if (m->m_len >= sizeof(*ip)) 555 ip = mtod(m, struct ip *); 556 else { 557 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf); 558 ip = &ipbuf; 559 } 560#ifdef _IP_VHL 561 v = _IP_VHL_V(ip->ip_vhl); 562#else 563 v = ip->ip_v; 564#endif 565 switch (v) { 566 case 4: 567 error = ipsec4_setspidx_ipaddr(m, spidx); 568 if (error) 569 return (error); 570 ipsec4_get_ulp(m, spidx, needport); 571 return (0); 572#ifdef INET6 573 case 6: 574 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 575 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 576 printf("%s: pkthdr len(%d) too small (v6), " 577 "ignored\n", __func__, m->m_pkthdr.len)); 578 return (EINVAL); 579 } 580 error = ipsec6_setspidx_ipaddr(m, spidx); 581 if (error) 582 return (error); 583 ipsec6_get_ulp(m, spidx, needport); 584 return (0); 585#endif 586 default: 587 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 588 printf("%s: " "unknown IP version %u, ignored.\n", 589 __func__, v)); 590 return (EINVAL); 591 } 592} 593 594static void 595ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 596{ 597 u_int8_t nxt; 598 int off; 599 600 /* Sanity check. */ 601 IPSEC_ASSERT(m != NULL, ("null mbuf")); 602 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short")); 603 604 /* NB: ip_input() flips it into host endian. XXX Need more checking. */ 605 if (m->m_len < sizeof (struct ip)) { 606 struct ip *ip = mtod(m, struct ip *); 607 if (ip->ip_off & (IP_MF | IP_OFFMASK)) 608 goto done; 609#ifdef _IP_VHL 610 off = _IP_VHL_HL(ip->ip_vhl) << 2; 611#else 612 off = ip->ip_hl << 2; 613#endif 614 nxt = ip->ip_p; 615 } else { 616 struct ip ih; 617 618 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih); 619 if (ih.ip_off & (IP_MF | IP_OFFMASK)) 620 goto done; 621#ifdef _IP_VHL 622 off = _IP_VHL_HL(ih.ip_vhl) << 2; 623#else 624 off = ih.ip_hl << 2; 625#endif 626 nxt = ih.ip_p; 627 } 628 629 while (off < m->m_pkthdr.len) { 630 struct ip6_ext ip6e; 631 struct tcphdr th; 632 struct udphdr uh; 633 634 switch (nxt) { 635 case IPPROTO_TCP: 636 spidx->ul_proto = nxt; 637 if (!needport) 638 goto done_proto; 639 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 640 goto done; 641 m_copydata(m, off, sizeof (th), (caddr_t) &th); 642 spidx->src.sin.sin_port = th.th_sport; 643 spidx->dst.sin.sin_port = th.th_dport; 644 return; 645 case IPPROTO_UDP: 646 spidx->ul_proto = nxt; 647 if (!needport) 648 goto done_proto; 649 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 650 goto done; 651 m_copydata(m, off, sizeof (uh), (caddr_t) &uh); 652 spidx->src.sin.sin_port = uh.uh_sport; 653 spidx->dst.sin.sin_port = uh.uh_dport; 654 return; 655 case IPPROTO_AH: 656 if (off + sizeof(ip6e) > m->m_pkthdr.len) 657 goto done; 658 /* XXX Sigh, this works but is totally bogus. */ 659 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e); 660 off += (ip6e.ip6e_len + 2) << 2; 661 nxt = ip6e.ip6e_nxt; 662 break; 663 case IPPROTO_ICMP: 664 default: 665 /* XXX Intermediate headers??? */ 666 spidx->ul_proto = nxt; 667 goto done_proto; 668 } 669 } 670done: 671 spidx->ul_proto = IPSEC_ULPROTO_ANY; 672done_proto: 673 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 674 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 675} 676 677/* Assumes that m is sane. */ 678static int 679ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 680{ 681 static const struct sockaddr_in template = { 682 sizeof (struct sockaddr_in), 683 AF_INET, 684 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 685 }; 686 687 spidx->src.sin = template; 688 spidx->dst.sin = template; 689 690 if (m->m_len < sizeof (struct ip)) { 691 m_copydata(m, offsetof(struct ip, ip_src), 692 sizeof (struct in_addr), 693 (caddr_t) &spidx->src.sin.sin_addr); 694 m_copydata(m, offsetof(struct ip, ip_dst), 695 sizeof (struct in_addr), 696 (caddr_t) &spidx->dst.sin.sin_addr); 697 } else { 698 struct ip *ip = mtod(m, struct ip *); 699 spidx->src.sin.sin_addr = ip->ip_src; 700 spidx->dst.sin.sin_addr = ip->ip_dst; 701 } 702 703 spidx->prefs = sizeof(struct in_addr) << 3; 704 spidx->prefd = sizeof(struct in_addr) << 3; 705 706 return (0); 707} 708 709#ifdef INET6 710static void 711ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 712{ 713 int off, nxt; 714 struct tcphdr th; 715 struct udphdr uh; 716 struct icmp6_hdr ih; 717 718 /* Sanity check. */ 719 if (m == NULL) 720 panic("%s: NULL pointer was passed.\n", __func__); 721 722 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 723 printf("%s:\n", __func__); kdebug_mbuf(m)); 724 725 /* Set default. */ 726 spidx->ul_proto = IPSEC_ULPROTO_ANY; 727 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 728 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 729 730 nxt = -1; 731 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 732 if (off < 0 || m->m_pkthdr.len < off) 733 return; 734 735 switch (nxt) { 736 case IPPROTO_TCP: 737 spidx->ul_proto = nxt; 738 if (!needport) 739 break; 740 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 741 break; 742 m_copydata(m, off, sizeof(th), (caddr_t)&th); 743 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 744 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 745 break; 746 case IPPROTO_UDP: 747 spidx->ul_proto = nxt; 748 if (!needport) 749 break; 750 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 751 break; 752 m_copydata(m, off, sizeof(uh), (caddr_t)&uh); 753 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 754 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 755 break; 756 case IPPROTO_ICMPV6: 757 spidx->ul_proto = nxt; 758 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 759 break; 760 m_copydata(m, off, sizeof(ih), (caddr_t)&ih); 761 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 762 htons((uint16_t)ih.icmp6_type); 763 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 764 htons((uint16_t)ih.icmp6_code); 765 break; 766 default: 767 /* XXX Intermediate headers??? */ 768 spidx->ul_proto = nxt; 769 break; 770 } 771} 772 773/* Assumes that m is sane. */ 774static int 775ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 776{ 777 struct ip6_hdr *ip6 = NULL; 778 struct ip6_hdr ip6buf; 779 struct sockaddr_in6 *sin6; 780 781 if (m->m_len >= sizeof(*ip6)) 782 ip6 = mtod(m, struct ip6_hdr *); 783 else { 784 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf); 785 ip6 = &ip6buf; 786 } 787 788 sin6 = (struct sockaddr_in6 *)&spidx->src; 789 bzero(sin6, sizeof(*sin6)); 790 sin6->sin6_family = AF_INET6; 791 sin6->sin6_len = sizeof(struct sockaddr_in6); 792 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src)); 793 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 794 sin6->sin6_addr.s6_addr16[1] = 0; 795 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 796 } 797 spidx->prefs = sizeof(struct in6_addr) << 3; 798 799 sin6 = (struct sockaddr_in6 *)&spidx->dst; 800 bzero(sin6, sizeof(*sin6)); 801 sin6->sin6_family = AF_INET6; 802 sin6->sin6_len = sizeof(struct sockaddr_in6); 803 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst)); 804 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 805 sin6->sin6_addr.s6_addr16[1] = 0; 806 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 807 } 808 spidx->prefd = sizeof(struct in6_addr) << 3; 809 810 return (0); 811} 812#endif 813 814static void 815ipsec_delpcbpolicy(struct inpcbpolicy *p) 816{ 817 818 free(p, M_IPSEC_INPCB); 819} 820 821/* Initialize policy in PCB. */ 822int 823ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp) 824{ 825 struct inpcbpolicy *new; 826 827 /* Sanity check. */ 828 if (so == NULL || pcb_sp == NULL) 829 panic("%s: NULL pointer was passed.\n", __func__); 830 831 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy), 832 M_IPSEC_INPCB, M_NOWAIT|M_ZERO); 833 if (new == NULL) { 834 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 835 return (ENOBUFS); 836 } 837 838 new->priv = IPSEC_IS_PRIVILEGED_SO(so); 839 840 if ((new->sp_in = KEY_NEWSP()) == NULL) { 841 ipsec_delpcbpolicy(new); 842 return (ENOBUFS); 843 } 844 new->sp_in->state = IPSEC_SPSTATE_ALIVE; 845 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 846 847 if ((new->sp_out = KEY_NEWSP()) == NULL) { 848 KEY_FREESP(&new->sp_in); 849 ipsec_delpcbpolicy(new); 850 return (ENOBUFS); 851 } 852 new->sp_out->state = IPSEC_SPSTATE_ALIVE; 853 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 854 855 *pcb_sp = new; 856 857 return (0); 858} 859 860/* Copy old IPsec policy into new. */ 861int 862ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new) 863{ 864 struct secpolicy *sp; 865 866 sp = ipsec_deepcopy_policy(old->sp_in); 867 if (sp) { 868 KEY_FREESP(&new->sp_in); 869 new->sp_in = sp; 870 } else 871 return (ENOBUFS); 872 873 sp = ipsec_deepcopy_policy(old->sp_out); 874 if (sp) { 875 KEY_FREESP(&new->sp_out); 876 new->sp_out = sp; 877 } else 878 return (ENOBUFS); 879 880 new->priv = old->priv; 881 882 return (0); 883} 884 885struct ipsecrequest * 886ipsec_newisr(void) 887{ 888 struct ipsecrequest *p; 889 890 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO); 891 if (p != NULL) 892 IPSECREQUEST_LOCK_INIT(p); 893 return (p); 894} 895 896void 897ipsec_delisr(struct ipsecrequest *p) 898{ 899 900 IPSECREQUEST_LOCK_DESTROY(p); 901 free(p, M_IPSEC_SR); 902} 903 904/* Deep-copy a policy in PCB. */ 905static struct secpolicy * 906ipsec_deepcopy_policy(struct secpolicy *src) 907{ 908 struct ipsecrequest *newchain = NULL; 909 struct ipsecrequest *p; 910 struct ipsecrequest **q; 911 struct ipsecrequest *r; 912 struct secpolicy *dst; 913 914 if (src == NULL) 915 return (NULL); 916 dst = KEY_NEWSP(); 917 if (dst == NULL) 918 return (NULL); 919 920 /* 921 * Deep-copy IPsec request chain. This is required since struct 922 * ipsecrequest is not reference counted. 923 */ 924 q = &newchain; 925 for (p = src->req; p; p = p->next) { 926 *q = ipsec_newisr(); 927 if (*q == NULL) 928 goto fail; 929 (*q)->saidx.proto = p->saidx.proto; 930 (*q)->saidx.mode = p->saidx.mode; 931 (*q)->level = p->level; 932 (*q)->saidx.reqid = p->saidx.reqid; 933 934 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src)); 935 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst)); 936 937 (*q)->sp = dst; 938 939 q = &((*q)->next); 940 } 941 942 dst->req = newchain; 943 dst->state = src->state; 944 dst->policy = src->policy; 945 /* Do not touch the refcnt fields. */ 946 947 return (dst); 948 949fail: 950 for (p = newchain; p; p = r) { 951 r = p->next; 952 ipsec_delisr(p); 953 p = NULL; 954 } 955 return (NULL); 956} 957 958/* Set policy and IPsec request if present. */ 959static int 960ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname, 961 caddr_t request, size_t len, struct ucred *cred) 962{ 963 struct sadb_x_policy *xpl; 964 struct secpolicy *newsp = NULL; 965 int error; 966 967 /* Sanity check. */ 968 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL) 969 return (EINVAL); 970 if (len < sizeof(*xpl)) 971 return (EINVAL); 972 xpl = (struct sadb_x_policy *)request; 973 974 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 975 printf("%s: passed policy\n", __func__); 976 kdebug_sadb_x_policy((struct sadb_ext *)xpl)); 977 978 /* Check policy type. */ 979 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */ 980 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 981 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 982 return (EINVAL); 983 984 /* Check privileged socket. */ 985 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 986 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0); 987 if (error) 988 return (EACCES); 989 } 990 991 /* Allocating new SP entry. */ 992 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 993 return (error); 994 995 newsp->state = IPSEC_SPSTATE_ALIVE; 996 997 /* Clear old SP and set new SP. */ 998 KEY_FREESP(pcb_sp); 999 *pcb_sp = newsp; 1000 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1001 printf("%s: new policy\n", __func__); 1002 kdebug_secpolicy(newsp)); 1003 1004 return (0); 1005} 1006 1007int 1008ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request, 1009 size_t len, struct ucred *cred) 1010{ 1011 struct sadb_x_policy *xpl; 1012 struct secpolicy **pcb_sp; 1013 1014 /* Sanity check. */ 1015 if (inp == NULL || request == NULL) 1016 return (EINVAL); 1017 if (len < sizeof(*xpl)) 1018 return (EINVAL); 1019 xpl = (struct sadb_x_policy *)request; 1020 1021 /* Select direction. */ 1022 switch (xpl->sadb_x_policy_dir) { 1023 case IPSEC_DIR_INBOUND: 1024 pcb_sp = &inp->inp_sp->sp_in; 1025 break; 1026 case IPSEC_DIR_OUTBOUND: 1027 pcb_sp = &inp->inp_sp->sp_out; 1028 break; 1029 default: 1030 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1031 xpl->sadb_x_policy_dir)); 1032 return (EINVAL); 1033 } 1034 1035 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred)); 1036} 1037 1038int 1039ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len, 1040 struct mbuf **mp) 1041{ 1042 struct sadb_x_policy *xpl; 1043 struct secpolicy *pcb_sp; 1044 1045 /* Sanity check. */ 1046 if (inp == NULL || request == NULL || mp == NULL) 1047 return (EINVAL); 1048 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 1049 if (len < sizeof(*xpl)) 1050 return (EINVAL); 1051 xpl = (struct sadb_x_policy *)request; 1052 1053 /* Select direction. */ 1054 switch (xpl->sadb_x_policy_dir) { 1055 case IPSEC_DIR_INBOUND: 1056 pcb_sp = inp->inp_sp->sp_in; 1057 break; 1058 case IPSEC_DIR_OUTBOUND: 1059 pcb_sp = inp->inp_sp->sp_out; 1060 break; 1061 default: 1062 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1063 xpl->sadb_x_policy_dir)); 1064 return (EINVAL); 1065 } 1066 1067 /* Sanity check. Should be an IPSEC_ASSERT. */ 1068 if (pcb_sp == NULL) 1069 return (EINVAL); 1070 1071 *mp = key_sp2msg(pcb_sp); 1072 if (!*mp) { 1073 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 1074 return (ENOBUFS); 1075 } 1076 1077 (*mp)->m_type = MT_DATA; 1078 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1079 printf("%s:\n", __func__); kdebug_mbuf(*mp)); 1080 1081 return (0); 1082} 1083 1084/* Delete policy in PCB. */ 1085int 1086ipsec_delete_pcbpolicy(struct inpcb *inp) 1087{ 1088 IPSEC_ASSERT(inp != NULL, ("null inp")); 1089 1090 if (inp->inp_sp == NULL) 1091 return (0); 1092 1093 if (inp->inp_sp->sp_in != NULL) 1094 KEY_FREESP(&inp->inp_sp->sp_in); 1095 1096 if (inp->inp_sp->sp_out != NULL) 1097 KEY_FREESP(&inp->inp_sp->sp_out); 1098 1099 ipsec_delpcbpolicy(inp->inp_sp); 1100 inp->inp_sp = NULL; 1101 1102 return (0); 1103} 1104 1105/* 1106 * Return current level. 1107 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1108 */ 1109u_int 1110ipsec_get_reqlevel(struct ipsecrequest *isr) 1111{ 1112 u_int level = 0; 1113 u_int esp_trans_deflev, esp_net_deflev; 1114 u_int ah_trans_deflev, ah_net_deflev; 1115 1116 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument")); 1117 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1118 ("af family mismatch, src %u, dst %u", 1119 isr->sp->spidx.src.sa.sa_family, 1120 isr->sp->spidx.dst.sa.sa_family)); 1121 1122/* XXX Note that we have ipseclog() expanded here - code sync issue. */ 1123#define IPSEC_CHECK_DEFAULT(lev) \ 1124 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1125 && (lev) != IPSEC_LEVEL_UNIQUE) \ 1126 ? (V_ipsec_debug \ 1127 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\ 1128 (lev), IPSEC_LEVEL_REQUIRE) \ 1129 : 0), \ 1130 (lev) = IPSEC_LEVEL_REQUIRE, \ 1131 (lev) \ 1132 : (lev)) 1133 1134 /* Set default level. */ 1135 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1136#ifdef INET 1137 case AF_INET: 1138 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev); 1139 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev); 1140 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev); 1141 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev); 1142 break; 1143#endif 1144#ifdef INET6 1145 case AF_INET6: 1146 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev); 1147 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev); 1148 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev); 1149 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev); 1150 break; 1151#endif /* INET6 */ 1152 default: 1153 panic("%s: unknown af %u", 1154 __func__, isr->sp->spidx.src.sa.sa_family); 1155 } 1156 1157#undef IPSEC_CHECK_DEFAULT 1158 1159 /* Set level. */ 1160 switch (isr->level) { 1161 case IPSEC_LEVEL_DEFAULT: 1162 switch (isr->saidx.proto) { 1163 case IPPROTO_ESP: 1164 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1165 level = esp_net_deflev; 1166 else 1167 level = esp_trans_deflev; 1168 break; 1169 case IPPROTO_AH: 1170 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1171 level = ah_net_deflev; 1172 else 1173 level = ah_trans_deflev; 1174 break; 1175 case IPPROTO_IPCOMP: 1176 /* 1177 * We don't really care, as IPcomp document says that 1178 * we shouldn't compress small packets. 1179 */ 1180 level = IPSEC_LEVEL_USE; 1181 break; 1182 default: 1183 panic("%s: Illegal protocol defined %u\n", __func__, 1184 isr->saidx.proto); 1185 } 1186 break; 1187 1188 case IPSEC_LEVEL_USE: 1189 case IPSEC_LEVEL_REQUIRE: 1190 level = isr->level; 1191 break; 1192 case IPSEC_LEVEL_UNIQUE: 1193 level = IPSEC_LEVEL_REQUIRE; 1194 break; 1195 1196 default: 1197 panic("%s: Illegal IPsec level %u\n", __func__, isr->level); 1198 } 1199 1200 return (level); 1201} 1202 1203/* 1204 * Check security policy requirements against the actual 1205 * packet contents. Return one if the packet should be 1206 * reject as "invalid"; otherwiser return zero to have the 1207 * packet treated as "valid". 1208 * 1209 * OUT: 1210 * 0: valid 1211 * 1: invalid 1212 */ 1213int 1214ipsec_in_reject(struct secpolicy *sp, struct mbuf *m) 1215{ 1216 struct ipsecrequest *isr; 1217 int need_auth; 1218 1219 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1220 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1221 1222 /* Check policy. */ 1223 switch (sp->policy) { 1224 case IPSEC_POLICY_DISCARD: 1225 return (1); 1226 case IPSEC_POLICY_BYPASS: 1227 case IPSEC_POLICY_NONE: 1228 return (0); 1229 } 1230 1231 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1232 ("invalid policy %u", sp->policy)); 1233 1234 /* XXX Should compare policy against IPsec header history. */ 1235 1236 need_auth = 0; 1237 for (isr = sp->req; isr != NULL; isr = isr->next) { 1238 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1239 continue; 1240 switch (isr->saidx.proto) { 1241 case IPPROTO_ESP: 1242 if ((m->m_flags & M_DECRYPTED) == 0) { 1243 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1244 printf("%s: ESP m_flags:%x\n", __func__, 1245 m->m_flags)); 1246 return (1); 1247 } 1248 1249 if (!need_auth && 1250 isr->sav != NULL && 1251 isr->sav->tdb_authalgxform != NULL && 1252 (m->m_flags & M_AUTHIPDGM) == 0) { 1253 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1254 printf("%s: ESP/AH m_flags:%x\n", __func__, 1255 m->m_flags)); 1256 return (1); 1257 } 1258 break; 1259 case IPPROTO_AH: 1260 need_auth = 1; 1261 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1262 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1263 printf("%s: AH m_flags:%x\n", __func__, 1264 m->m_flags)); 1265 return (1); 1266 } 1267 break; 1268 case IPPROTO_IPCOMP: 1269 /* 1270 * We don't really care, as IPcomp document 1271 * says that we shouldn't compress small 1272 * packets. IPComp policy should always be 1273 * treated as being in "use" level. 1274 */ 1275 break; 1276 } 1277 } 1278 return (0); /* Valid. */ 1279} 1280 1281static int 1282ipsec46_in_reject(struct mbuf *m, struct inpcb *inp) 1283{ 1284 struct secpolicy *sp; 1285 int error; 1286 int result; 1287 1288 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1289 1290 /* 1291 * Get SP for this packet. 1292 * When we are called from ip_forward(), we call 1293 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1294 */ 1295 if (inp == NULL) 1296 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1297 else 1298 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error); 1299 1300 if (sp != NULL) { 1301 result = ipsec_in_reject(sp, m); 1302 KEY_FREESP(&sp); 1303 } else { 1304 result = 0; /* XXX Should be panic? 1305 * -> No, there may be error. */ 1306 } 1307 return (result); 1308} 1309 1310/* 1311 * Check AH/ESP integrity. 1312 * This function is called from tcp_input(), udp_input(), 1313 * and {ah,esp}4_input for tunnel mode. 1314 */ 1315int 1316ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1317{ 1318 int result; 1319 1320 result = ipsec46_in_reject(m, inp); 1321 if (result) 1322 V_ipsec4stat.ips_in_polvio++; 1323 1324 return (result); 1325} 1326 1327#ifdef INET6 1328/* 1329 * Check AH/ESP integrity. 1330 * This function is called from tcp6_input(), udp6_input(), 1331 * and {ah,esp}6_input for tunnel mode. 1332 */ 1333int 1334ipsec6_in_reject(struct mbuf *m, struct inpcb *inp) 1335{ 1336 int result; 1337 1338 result = ipsec46_in_reject(m, inp); 1339 if (result) 1340 V_ipsec6stat.ips_in_polvio++; 1341 1342 return (result); 1343} 1344#endif 1345 1346/* 1347 * Compute the byte size to be occupied by IPsec header. 1348 * In case it is tunnelled, it includes the size of outer IP header. 1349 * NOTE: SP passed is freed in this function. 1350 */ 1351static size_t 1352ipsec_hdrsiz_internal(struct secpolicy *sp) 1353{ 1354 struct ipsecrequest *isr; 1355 size_t size; 1356 1357 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1358 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1359 1360 switch (sp->policy) { 1361 case IPSEC_POLICY_DISCARD: 1362 case IPSEC_POLICY_BYPASS: 1363 case IPSEC_POLICY_NONE: 1364 return (0); 1365 } 1366 1367 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1368 ("invalid policy %u", sp->policy)); 1369 1370 size = 0; 1371 for (isr = sp->req; isr != NULL; isr = isr->next) { 1372 size_t clen = 0; 1373 1374 switch (isr->saidx.proto) { 1375 case IPPROTO_ESP: 1376 clen = esp_hdrsiz(isr->sav); 1377 break; 1378 case IPPROTO_AH: 1379 clen = ah_hdrsiz(isr->sav); 1380 break; 1381 case IPPROTO_IPCOMP: 1382 clen = sizeof(struct ipcomp); 1383 break; 1384 } 1385 1386 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1387 switch (isr->saidx.dst.sa.sa_family) { 1388 case AF_INET: 1389 clen += sizeof(struct ip); 1390 break; 1391#ifdef INET6 1392 case AF_INET6: 1393 clen += sizeof(struct ip6_hdr); 1394 break; 1395#endif 1396 default: 1397 ipseclog((LOG_ERR, "%s: unknown AF %d in " 1398 "IPsec tunnel SA\n", __func__, 1399 ((struct sockaddr *)&isr->saidx.dst)->sa_family)); 1400 break; 1401 } 1402 } 1403 size += clen; 1404 } 1405 1406 return (size); 1407} 1408 1409/* 1410 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(), 1411 * disabled ip6_ipsec_mtu() and ip6_forward(). 1412 */ 1413size_t 1414ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1415{ 1416 struct secpolicy *sp; 1417 int error; 1418 size_t size; 1419 1420 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1421 1422 /* Get SP for this packet. 1423 * When we are called from ip_forward(), we call 1424 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1425 */ 1426 if (inp == NULL) 1427 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1428 else 1429 sp = ipsec_getpolicybysock(m, dir, inp, &error); 1430 1431 if (sp != NULL) { 1432 size = ipsec_hdrsiz_internal(sp); 1433 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1434 printf("%s: size:%lu.\n", __func__, 1435 (unsigned long)size)); 1436 1437 KEY_FREESP(&sp); 1438 } else { 1439 size = 0; /* XXX Should be panic? 1440 * -> No, we are called w/o knowing if 1441 * IPsec processing is needed. */ 1442 } 1443 return (size); 1444} 1445 1446/* 1447 * Check the variable replay window. 1448 * ipsec_chkreplay() performs replay check before ICV verification. 1449 * ipsec_updatereplay() updates replay bitmap. This must be called after 1450 * ICV verification (it also performs replay check, which is usually done 1451 * beforehand). 1452 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1453 * 1454 * Based on RFC 2401. 1455 */ 1456int 1457ipsec_chkreplay(u_int32_t seq, struct secasvar *sav) 1458{ 1459 const struct secreplay *replay; 1460 u_int32_t diff; 1461 int fr; 1462 u_int32_t wsizeb; /* Constant: bits of window size. */ 1463 int frlast; /* Constant: last frame. */ 1464 1465 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1466 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1467 1468 replay = sav->replay; 1469 1470 if (replay->wsize == 0) 1471 return (1); /* No need to check replay. */ 1472 1473 /* Constant. */ 1474 frlast = replay->wsize - 1; 1475 wsizeb = replay->wsize << 3; 1476 1477 /* Sequence number of 0 is invalid. */ 1478 if (seq == 0) 1479 return (0); 1480 1481 /* First time is always okay. */ 1482 if (replay->count == 0) 1483 return (1); 1484 1485 if (seq > replay->lastseq) { 1486 /* Larger sequences are okay. */ 1487 return (1); 1488 } else { 1489 /* seq is equal or less than lastseq. */ 1490 diff = replay->lastseq - seq; 1491 1492 /* Over range to check, i.e. too old or wrapped. */ 1493 if (diff >= wsizeb) 1494 return (0); 1495 1496 fr = frlast - diff / 8; 1497 1498 /* This packet already seen? */ 1499 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1500 return (0); 1501 1502 /* Out of order but good. */ 1503 return (1); 1504 } 1505} 1506 1507/* 1508 * Check replay counter whether to update or not. 1509 * OUT: 0: OK 1510 * 1: NG 1511 */ 1512int 1513ipsec_updatereplay(u_int32_t seq, struct secasvar *sav) 1514{ 1515 struct secreplay *replay; 1516 u_int32_t diff; 1517 int fr; 1518 u_int32_t wsizeb; /* Constant: bits of window size. */ 1519 int frlast; /* Constant: last frame. */ 1520 1521 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1522 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1523 1524 replay = sav->replay; 1525 1526 if (replay->wsize == 0) 1527 goto ok; /* No need to check replay. */ 1528 1529 /* Constant. */ 1530 frlast = replay->wsize - 1; 1531 wsizeb = replay->wsize << 3; 1532 1533 /* Sequence number of 0 is invalid. */ 1534 if (seq == 0) 1535 return (1); 1536 1537 /* First time. */ 1538 if (replay->count == 0) { 1539 replay->lastseq = seq; 1540 bzero(replay->bitmap, replay->wsize); 1541 (replay->bitmap)[frlast] = 1; 1542 goto ok; 1543 } 1544 1545 if (seq > replay->lastseq) { 1546 /* seq is larger than lastseq. */ 1547 diff = seq - replay->lastseq; 1548 1549 /* New larger sequence number. */ 1550 if (diff < wsizeb) { 1551 /* In window. */ 1552 /* Set bit for this packet. */ 1553 vshiftl(replay->bitmap, diff, replay->wsize); 1554 (replay->bitmap)[frlast] |= 1; 1555 } else { 1556 /* This packet has a "way larger". */ 1557 bzero(replay->bitmap, replay->wsize); 1558 (replay->bitmap)[frlast] = 1; 1559 } 1560 replay->lastseq = seq; 1561 1562 /* Larger is good. */ 1563 } else { 1564 /* seq is equal or less than lastseq. */ 1565 diff = replay->lastseq - seq; 1566 1567 /* Over range to check, i.e. too old or wrapped. */ 1568 if (diff >= wsizeb) 1569 return (1); 1570 1571 fr = frlast - diff / 8; 1572 1573 /* This packet already seen? */ 1574 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1575 return (1); 1576 1577 /* Mark as seen. */ 1578 (replay->bitmap)[fr] |= (1 << (diff % 8)); 1579 1580 /* Out of order but good. */ 1581 } 1582 1583ok: 1584 if (replay->count == ~0) { 1585 1586 /* Set overflow flag. */ 1587 replay->overflow++; 1588 1589 /* Don't increment, no more packets accepted. */ 1590 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 1591 return (1); 1592 1593 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1594 __func__, replay->overflow, ipsec_logsastr(sav))); 1595 } 1596 1597 replay->count++; 1598 1599 return (0); 1600} 1601 1602/* 1603 * Shift variable length buffer to left. 1604 * IN: bitmap: pointer to the buffer 1605 * nbit: the number of to shift. 1606 * wsize: buffer size (bytes). 1607 */ 1608static void 1609vshiftl(unsigned char *bitmap, int nbit, int wsize) 1610{ 1611 int s, j, i; 1612 unsigned char over; 1613 1614 for (j = 0; j < nbit; j += 8) { 1615 s = (nbit - j < 8) ? (nbit - j): 8; 1616 bitmap[0] <<= s; 1617 for (i = 1; i < wsize; i++) { 1618 over = (bitmap[i] >> (8 - s)); 1619 bitmap[i] <<= s; 1620 bitmap[i-1] |= over; 1621 } 1622 } 1623} 1624 1625#ifdef INET 1626/* Return a printable string for the IPv4 address. */ 1627static char * 1628inet_ntoa4(struct in_addr ina) 1629{ 1630 static char buf[4][4 * sizeof "123" + 4]; 1631 unsigned char *ucp = (unsigned char *) &ina; 1632 static int i = 3; 1633 1634 /* XXX-BZ Returns static buffer. */ 1635 i = (i + 1) % 4; 1636 sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff, 1637 ucp[2] & 0xff, ucp[3] & 0xff); 1638 return (buf[i]); 1639} 1640#endif 1641 1642/* Return a printable string for the address. */ 1643char * 1644ipsec_address(union sockaddr_union* sa) 1645{ 1646#ifdef INET6 1647 char ip6buf[INET6_ADDRSTRLEN]; 1648#endif 1649 1650 switch (sa->sa.sa_family) { 1651#ifdef INET 1652 case AF_INET: 1653 return (inet_ntoa4(sa->sin.sin_addr)); 1654#endif /* INET */ 1655#ifdef INET6 1656 case AF_INET6: 1657 return (ip6_sprintf(ip6buf, &sa->sin6.sin6_addr)); 1658#endif /* INET6 */ 1659 default: 1660 return ("(unknown address family)"); 1661 } 1662} 1663 1664const char * 1665ipsec_logsastr(struct secasvar *sav) 1666{ 1667 static char buf[256]; 1668 char *p; 1669 struct secasindex *saidx = &sav->sah->saidx; 1670 1671 IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 1672 ("address family mismatch")); 1673 1674 p = buf; 1675 snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi)); 1676 while (p && *p) 1677 p++; 1678 /* NB: only use ipsec_address on one address at a time. */ 1679 snprintf(p, sizeof (buf) - (p - buf), "src=%s ", 1680 ipsec_address(&saidx->src)); 1681 while (p && *p) 1682 p++; 1683 snprintf(p, sizeof (buf) - (p - buf), "dst=%s)", 1684 ipsec_address(&saidx->dst)); 1685 1686 return (buf); 1687} 1688 1689void 1690ipsec_dumpmbuf(struct mbuf *m) 1691{ 1692 int totlen; 1693 int i; 1694 u_char *p; 1695 1696 totlen = 0; 1697 printf("---\n"); 1698 while (m) { 1699 p = mtod(m, u_char *); 1700 for (i = 0; i < m->m_len; i++) { 1701 printf("%02x ", p[i]); 1702 totlen++; 1703 if (totlen % 16 == 0) 1704 printf("\n"); 1705 } 1706 m = m->m_next; 1707 } 1708 if (totlen % 16 != 0) 1709 printf("\n"); 1710 printf("---\n"); 1711} 1712 1713static void 1714ipsec_attach(const void *unused __unused) 1715{ 1716 1717#ifdef VIMAGE 1718 vnet_mod_register(&vnet_ipsec_modinfo); 1719#else 1720 ipsec_iattach(NULL); 1721#endif 1722} 1723 1724static int 1725ipsec_iattach(const void *unused __unused) 1726{ 1727 1728 SECPOLICY_LOCK_INIT(&V_ip4_def_policy); 1729 V_ip4_def_policy.refcnt = 1; /* NB: disallow free. */ 1730 1731 return (0); 1732} 1733 1734SYSINIT(ipsec, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST, ipsec_attach, NULL); 1735 1736 1737/* XXX This stuff doesn't belong here... */ 1738 1739static struct xformsw* xforms = NULL; 1740 1741/* 1742 * Register a transform; typically at system startup. 1743 */ 1744void 1745xform_register(struct xformsw* xsp) 1746{ 1747 1748 xsp->xf_next = xforms; 1749 xforms = xsp; 1750} 1751 1752/* 1753 * Initialize transform support in an sav. 1754 */ 1755int 1756xform_init(struct secasvar *sav, int xftype) 1757{ 1758 struct xformsw *xsp; 1759 1760 if (sav->tdb_xform != NULL) /* Previously initialized. */ 1761 return (0); 1762 for (xsp = xforms; xsp; xsp = xsp->xf_next) 1763 if (xsp->xf_type == xftype) 1764 return ((*xsp->xf_init)(sav, xsp)); 1765 return (EINVAL); 1766} 1767