1/* $FreeBSD$ */ 2/* $KAME: ipsec.c,v 1.103 2001/05/24 07:14:18 sakane Exp $ */ 3 4/*- 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33/* 34 * IPsec controller part. 35 */ 36 37#include "opt_inet.h" 38#include "opt_inet6.h" 39#include "opt_ipsec.h" 40 41#include <sys/param.h> 42#include <sys/systm.h> 43#include <sys/malloc.h> 44#include <sys/mbuf.h> 45#include <sys/domain.h> 46#include <sys/priv.h> 47#include <sys/protosw.h> 48#include <sys/socket.h> 49#include <sys/socketvar.h> 50#include <sys/errno.h> 51#include <sys/time.h> 52#include <sys/kernel.h> 53#include <sys/syslog.h> 54#include <sys/sysctl.h> 55#include <sys/proc.h> 56 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_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 129FEATURE(ipsec, "Internet Protocol Security (IPsec)"); 130#ifdef IPSEC_NAT_T 131FEATURE(ipsec_natt, "UDP Encapsulation of IPsec ESP Packets ('NAT-T')"); 132#endif 133 134SYSCTL_DECL(_net_inet_ipsec); 135 136/* net.inet.ipsec */ 137SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy, 138 CTLFLAG_RW, &VNET_NAME(ip4_def_policy).policy, 0, 139 "IPsec default policy."); 140SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev, 141 CTLFLAG_RW, &VNET_NAME(ip4_esp_trans_deflev), 0, 142 "Default ESP transport mode level"); 143SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev, 144 CTLFLAG_RW, &VNET_NAME(ip4_esp_net_deflev), 0, 145 "Default ESP tunnel mode level."); 146SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev, 147 CTLFLAG_RW, &VNET_NAME(ip4_ah_trans_deflev), 0, 148 "AH transfer mode default level."); 149SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev, 150 CTLFLAG_RW, &VNET_NAME(ip4_ah_net_deflev), 0, 151 "AH tunnel mode default level."); 152SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos, 153 CTLFLAG_RW, &VNET_NAME(ah_cleartos), 0, 154 "If set clear type-of-service field when doing AH computation."); 155SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, ah_offsetmask, 156 CTLFLAG_RW, &VNET_NAME(ip4_ah_offsetmask), 0, 157 "If not set clear offset field mask when doing AH computation."); 158SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit, 159 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_dfbit), 0, 160 "Do not fragment bit on encap."); 161SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn, 162 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_ecn), 0, 163 "Explicit Congestion Notification handling."); 164SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEBUG, debug, 165 CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0, 166 "Enable IPsec debugging output when set."); 167SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, crypto_support, 168 CTLFLAG_RW, &VNET_NAME(crypto_support), 0, 169 "Crypto driver selection."); 170SYSCTL_VNET_STRUCT(_net_inet_ipsec, OID_AUTO, ipsecstats, 171 CTLFLAG_RD, &VNET_NAME(ipsec4stat), ipsecstat, 172 "IPsec IPv4 statistics."); 173 174#ifdef REGRESSION 175/* 176 * When set to 1, IPsec will send packets with the same sequence number. 177 * This allows to verify if the other side has proper replay attacks detection. 178 */ 179VNET_DEFINE(int, ipsec_replay) = 0; 180SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_replay, 181 CTLFLAG_RW, &VNET_NAME(ipsec_replay), 0, 182 "Emulate replay attack"); 183/* 184 * When set 1, IPsec will send packets with corrupted HMAC. 185 * This allows to verify if the other side properly detects modified packets. 186 */ 187VNET_DEFINE(int, ipsec_integrity) = 0; 188SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_integrity, 189 CTLFLAG_RW, &VNET_NAME(ipsec_integrity), 0, 190 "Emulate man-in-the-middle attack"); 191#endif 192 193#ifdef INET6 194VNET_DEFINE(struct ipsecstat, ipsec6stat); 195VNET_DEFINE(int, ip6_esp_trans_deflev) = IPSEC_LEVEL_USE; 196VNET_DEFINE(int, ip6_esp_net_deflev) = IPSEC_LEVEL_USE; 197VNET_DEFINE(int, ip6_ah_trans_deflev) = IPSEC_LEVEL_USE; 198VNET_DEFINE(int, ip6_ah_net_deflev) = IPSEC_LEVEL_USE; 199VNET_DEFINE(int, ip6_ipsec_ecn) = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 200 201SYSCTL_DECL(_net_inet6_ipsec6); 202 203/* net.inet6.ipsec6 */ 204#ifdef COMPAT_KAME 205SYSCTL_OID(_net_inet6_ipsec6, IPSECCTL_STATS, stats, CTLFLAG_RD, 206 0, 0, compat_ipsecstats_sysctl, "S", "IPsec IPv6 statistics."); 207#endif /* COMPAT_KAME */ 208SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy, CTLFLAG_RW, 209 &VNET_NAME(ip4_def_policy).policy, 0, 210 "IPsec default policy."); 211SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV, 212 esp_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_trans_deflev), 0, 213 "Default ESP transport mode level."); 214SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV, 215 esp_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_net_deflev), 0, 216 "Default ESP tunnel mode level."); 217SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV, 218 ah_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_trans_deflev), 0, 219 "AH transfer mode default level."); 220SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV, 221 ah_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_net_deflev), 0, 222 "AH tunnel mode default level."); 223SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_ECN, 224 ecn, CTLFLAG_RW, &VNET_NAME(ip6_ipsec_ecn), 0, 225 "Explicit Congestion Notification handling."); 226SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEBUG, debug, CTLFLAG_RW, 227 &VNET_NAME(ipsec_debug), 0, 228 "Enable IPsec debugging output when set."); 229SYSCTL_VNET_STRUCT(_net_inet6_ipsec6, IPSECCTL_STATS, 230 ipsecstats, CTLFLAG_RD, &VNET_NAME(ipsec6stat), ipsecstat, 231 "IPsec IPv6 statistics."); 232#endif /* INET6 */ 233 234static int ipsec_setspidx_inpcb __P((struct mbuf *, struct inpcb *)); 235static int ipsec_setspidx __P((struct mbuf *, struct secpolicyindex *, int)); 236static void ipsec4_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 237static int ipsec4_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 238#ifdef INET6 239static void ipsec6_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 240static int ipsec6_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 241#endif 242static void ipsec_delpcbpolicy __P((struct inpcbpolicy *)); 243static struct secpolicy *ipsec_deepcopy_policy __P((struct secpolicy *src)); 244static void vshiftl __P((unsigned char *, int, int)); 245 246MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy"); 247 248/* 249 * Return a held reference to the default SP. 250 */ 251static struct secpolicy * 252key_allocsp_default(const char* where, int tag) 253{ 254 struct secpolicy *sp; 255 256 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 257 printf("DP key_allocsp_default from %s:%u\n", where, tag)); 258 259 sp = &V_ip4_def_policy; 260 if (sp->policy != IPSEC_POLICY_DISCARD && 261 sp->policy != IPSEC_POLICY_NONE) { 262 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n", 263 sp->policy, IPSEC_POLICY_NONE)); 264 sp->policy = IPSEC_POLICY_NONE; 265 } 266 key_addref(sp); 267 268 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 269 printf("DP key_allocsp_default returns SP:%p (%u)\n", 270 sp, sp->refcnt)); 271 return (sp); 272} 273#define KEY_ALLOCSP_DEFAULT() \ 274 key_allocsp_default(__FILE__, __LINE__) 275 276/* 277 * For OUTBOUND packet having a socket. Searching SPD for packet, 278 * and return a pointer to SP. 279 * OUT: NULL: no apropreate SP found, the following value is set to error. 280 * 0 : bypass 281 * EACCES : discard packet. 282 * ENOENT : ipsec_acquire() in progress, maybe. 283 * others : error occured. 284 * others: a pointer to SP 285 * 286 * NOTE: IPv6 mapped adddress concern is implemented here. 287 */ 288struct secpolicy * 289ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir) 290{ 291 struct secpolicy *sp; 292 293 IPSEC_ASSERT(tdbi != NULL, ("null tdbi")); 294 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 295 ("invalid direction %u", dir)); 296 297 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir); 298 if (sp == NULL) /*XXX????*/ 299 sp = KEY_ALLOCSP_DEFAULT(); 300 IPSEC_ASSERT(sp != NULL, ("null SP")); 301 return (sp); 302} 303 304/* 305 * For OUTBOUND packet having a socket. Searching SPD for packet, 306 * and return a pointer to SP. 307 * OUT: NULL: no apropreate SP found, the following value is set to error. 308 * 0 : bypass 309 * EACCES : discard packet. 310 * ENOENT : ipsec_acquire() in progress, maybe. 311 * others : error occured. 312 * others: a pointer to SP 313 * 314 * NOTE: IPv6 mapped adddress concern is implemented here. 315 */ 316static struct secpolicy * 317ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb *inp, int *error) 318{ 319 struct inpcbpolicy *pcbsp; 320 struct secpolicy *currsp = NULL; /* Policy on socket. */ 321 struct secpolicy *sp; 322 323 IPSEC_ASSERT(m != NULL, ("null mbuf")); 324 IPSEC_ASSERT(inp != NULL, ("null inpcb")); 325 IPSEC_ASSERT(error != NULL, ("null error")); 326 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 327 ("invalid direction %u", dir)); 328 329 /* Set spidx in pcb. */ 330 *error = ipsec_setspidx_inpcb(m, inp); 331 if (*error) 332 return (NULL); 333 334 pcbsp = inp->inp_sp; 335 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp")); 336 switch (dir) { 337 case IPSEC_DIR_INBOUND: 338 currsp = pcbsp->sp_in; 339 break; 340 case IPSEC_DIR_OUTBOUND: 341 currsp = pcbsp->sp_out; 342 break; 343 } 344 IPSEC_ASSERT(currsp != NULL, ("null currsp")); 345 346 if (pcbsp->priv) { /* When privilieged socket. */ 347 switch (currsp->policy) { 348 case IPSEC_POLICY_BYPASS: 349 case IPSEC_POLICY_IPSEC: 350 key_addref(currsp); 351 sp = currsp; 352 break; 353 354 case IPSEC_POLICY_ENTRUST: 355 /* Look for a policy in SPD. */ 356 sp = KEY_ALLOCSP(&currsp->spidx, dir); 357 if (sp == NULL) /* No SP found. */ 358 sp = KEY_ALLOCSP_DEFAULT(); 359 break; 360 361 default: 362 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n", 363 __func__, currsp->policy)); 364 *error = EINVAL; 365 return (NULL); 366 } 367 } else { /* Unpriv, SPD has policy. */ 368 sp = KEY_ALLOCSP(&currsp->spidx, dir); 369 if (sp == NULL) { /* No SP found. */ 370 switch (currsp->policy) { 371 case IPSEC_POLICY_BYPASS: 372 ipseclog((LOG_ERR, "%s: Illegal policy for " 373 "non-priviliged defined %d\n", 374 __func__, currsp->policy)); 375 *error = EINVAL; 376 return (NULL); 377 378 case IPSEC_POLICY_ENTRUST: 379 sp = KEY_ALLOCSP_DEFAULT(); 380 break; 381 382 case IPSEC_POLICY_IPSEC: 383 key_addref(currsp); 384 sp = currsp; 385 break; 386 387 default: 388 ipseclog((LOG_ERR, "%s: Invalid policy for " 389 "PCB %d\n", __func__, currsp->policy)); 390 *error = EINVAL; 391 return (NULL); 392 } 393 } 394 } 395 IPSEC_ASSERT(sp != NULL, 396 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy)); 397 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 398 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n", 399 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt)); 400 return (sp); 401} 402 403/* 404 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 405 * and return a pointer to SP. 406 * OUT: positive: a pointer to the entry for security policy leaf matched. 407 * NULL: no apropreate SP found, the following value is set to error. 408 * 0 : bypass 409 * EACCES : discard packet. 410 * ENOENT : ipsec_acquire() in progress, maybe. 411 * others : error occured. 412 */ 413struct secpolicy * 414ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 415{ 416 struct secpolicyindex spidx; 417 struct secpolicy *sp; 418 419 IPSEC_ASSERT(m != NULL, ("null mbuf")); 420 IPSEC_ASSERT(error != NULL, ("null error")); 421 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 422 ("invalid direction %u", dir)); 423 424 sp = NULL; 425 if (key_havesp(dir)) { 426 /* Make an index to look for a policy. */ 427 *error = ipsec_setspidx(m, &spidx, 428 (flag & IP_FORWARDING) ? 0 : 1); 429 if (*error != 0) { 430 DPRINTF(("%s: setpidx failed, dir %u flag %u\n", 431 __func__, dir, flag)); 432 return (NULL); 433 } 434 spidx.dir = dir; 435 436 sp = KEY_ALLOCSP(&spidx, dir); 437 } 438 if (sp == NULL) /* No SP found, use system default. */ 439 sp = KEY_ALLOCSP_DEFAULT(); 440 IPSEC_ASSERT(sp != NULL, ("null SP")); 441 return (sp); 442} 443 444struct secpolicy * 445ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 446 struct inpcb *inp) 447{ 448 struct secpolicy *sp; 449 450 *error = 0; 451 if (inp == NULL) 452 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 453 else 454 sp = ipsec_getpolicybysock(m, dir, inp, error); 455 if (sp == NULL) { 456 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error")); 457 IPSECSTAT_INC(ips_out_inval); 458 return (NULL); 459 } 460 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error)); 461 switch (sp->policy) { 462 case IPSEC_POLICY_ENTRUST: 463 default: 464 printf("%s: invalid policy %u\n", __func__, sp->policy); 465 /* FALLTHROUGH */ 466 case IPSEC_POLICY_DISCARD: 467 IPSECSTAT_INC(ips_out_polvio); 468 *error = -EINVAL; /* Packet is discarded by caller. */ 469 break; 470 case IPSEC_POLICY_BYPASS: 471 case IPSEC_POLICY_NONE: 472 KEY_FREESP(&sp); 473 sp = NULL; /* NB: force NULL result. */ 474 break; 475 case IPSEC_POLICY_IPSEC: 476 if (sp->req == NULL) /* Acquire a SA. */ 477 *error = key_spdacquire(sp); 478 break; 479 } 480 if (*error != 0) { 481 KEY_FREESP(&sp); 482 sp = NULL; 483 } 484 return (sp); 485} 486 487static int 488ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp) 489{ 490 int error; 491 492 IPSEC_ASSERT(inp != NULL, ("null inp")); 493 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 494 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL, 495 ("null sp_in || sp_out")); 496 497 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1); 498 if (error == 0) { 499 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 500 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx; 501 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 502 } else { 503 bzero(&inp->inp_sp->sp_in->spidx, 504 sizeof (inp->inp_sp->sp_in->spidx)); 505 bzero(&inp->inp_sp->sp_out->spidx, 506 sizeof (inp->inp_sp->sp_in->spidx)); 507 } 508 return (error); 509} 510 511/* 512 * Configure security policy index (src/dst/proto/sport/dport) 513 * by looking at the content of mbuf. 514 * The caller is responsible for error recovery (like clearing up spidx). 515 */ 516static int 517ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 518{ 519 struct ip *ip = NULL; 520 struct ip ipbuf; 521 u_int v; 522 struct mbuf *n; 523 int len; 524 int error; 525 526 IPSEC_ASSERT(m != NULL, ("null mbuf")); 527 528 /* 529 * Validate m->m_pkthdr.len. We see incorrect length if we 530 * mistakenly call this function with inconsistent mbuf chain 531 * (like 4.4BSD tcp/udp processing). XXX Should we panic here? 532 */ 533 len = 0; 534 for (n = m; n; n = n->m_next) 535 len += n->m_len; 536 if (m->m_pkthdr.len != len) { 537 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 538 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n", 539 __func__, len, m->m_pkthdr.len)); 540 return (EINVAL); 541 } 542 543 if (m->m_pkthdr.len < sizeof(struct ip)) { 544 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 545 printf("%s: pkthdr len(%d) too small (v4), ignored.\n", 546 __func__, m->m_pkthdr.len)); 547 return (EINVAL); 548 } 549 550 if (m->m_len >= sizeof(*ip)) 551 ip = mtod(m, struct ip *); 552 else { 553 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf); 554 ip = &ipbuf; 555 } 556 v = ip->ip_v; 557 switch (v) { 558 case 4: 559 error = ipsec4_setspidx_ipaddr(m, spidx); 560 if (error) 561 return (error); 562 ipsec4_get_ulp(m, spidx, needport); 563 return (0); 564#ifdef INET6 565 case 6: 566 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 567 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 568 printf("%s: pkthdr len(%d) too small (v6), " 569 "ignored\n", __func__, m->m_pkthdr.len)); 570 return (EINVAL); 571 } 572 error = ipsec6_setspidx_ipaddr(m, spidx); 573 if (error) 574 return (error); 575 ipsec6_get_ulp(m, spidx, needport); 576 return (0); 577#endif 578 default: 579 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 580 printf("%s: " "unknown IP version %u, ignored.\n", 581 __func__, v)); 582 return (EINVAL); 583 } 584} 585 586static void 587ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 588{ 589 u_int8_t nxt; 590 int off; 591 592 /* Sanity check. */ 593 IPSEC_ASSERT(m != NULL, ("null mbuf")); 594 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short")); 595 596 /* NB: ip_input() flips it into host endian. XXX Need more checking. */ 597 if (m->m_len >= sizeof (struct ip)) { 598 struct ip *ip = mtod(m, struct ip *); 599 if (ip->ip_off & (IP_MF | IP_OFFMASK)) 600 goto done; 601 off = ip->ip_hl << 2; 602 nxt = ip->ip_p; 603 } else { 604 struct ip ih; 605 606 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih); 607 if (ih.ip_off & (IP_MF | IP_OFFMASK)) 608 goto done; 609 off = ih.ip_hl << 2; 610 nxt = ih.ip_p; 611 } 612 613 while (off < m->m_pkthdr.len) { 614 struct ip6_ext ip6e; 615 struct tcphdr th; 616 struct udphdr uh; 617 618 switch (nxt) { 619 case IPPROTO_TCP: 620 spidx->ul_proto = nxt; 621 if (!needport) 622 goto done_proto; 623 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 624 goto done; 625 m_copydata(m, off, sizeof (th), (caddr_t) &th); 626 spidx->src.sin.sin_port = th.th_sport; 627 spidx->dst.sin.sin_port = th.th_dport; 628 return; 629 case IPPROTO_UDP: 630 spidx->ul_proto = nxt; 631 if (!needport) 632 goto done_proto; 633 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 634 goto done; 635 m_copydata(m, off, sizeof (uh), (caddr_t) &uh); 636 spidx->src.sin.sin_port = uh.uh_sport; 637 spidx->dst.sin.sin_port = uh.uh_dport; 638 return; 639 case IPPROTO_AH: 640 if (off + sizeof(ip6e) > m->m_pkthdr.len) 641 goto done; 642 /* XXX Sigh, this works but is totally bogus. */ 643 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e); 644 off += (ip6e.ip6e_len + 2) << 2; 645 nxt = ip6e.ip6e_nxt; 646 break; 647 case IPPROTO_ICMP: 648 default: 649 /* XXX Intermediate headers??? */ 650 spidx->ul_proto = nxt; 651 goto done_proto; 652 } 653 } 654done: 655 spidx->ul_proto = IPSEC_ULPROTO_ANY; 656done_proto: 657 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 658 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 659} 660 661/* Assumes that m is sane. */ 662static int 663ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 664{ 665 static const struct sockaddr_in template = { 666 sizeof (struct sockaddr_in), 667 AF_INET, 668 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 669 }; 670 671 spidx->src.sin = template; 672 spidx->dst.sin = template; 673 674 if (m->m_len < sizeof (struct ip)) { 675 m_copydata(m, offsetof(struct ip, ip_src), 676 sizeof (struct in_addr), 677 (caddr_t) &spidx->src.sin.sin_addr); 678 m_copydata(m, offsetof(struct ip, ip_dst), 679 sizeof (struct in_addr), 680 (caddr_t) &spidx->dst.sin.sin_addr); 681 } else { 682 struct ip *ip = mtod(m, struct ip *); 683 spidx->src.sin.sin_addr = ip->ip_src; 684 spidx->dst.sin.sin_addr = ip->ip_dst; 685 } 686 687 spidx->prefs = sizeof(struct in_addr) << 3; 688 spidx->prefd = sizeof(struct in_addr) << 3; 689 690 return (0); 691} 692 693#ifdef INET6 694static void 695ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 696{ 697 int off, nxt; 698 struct tcphdr th; 699 struct udphdr uh; 700 struct icmp6_hdr ih; 701 702 /* Sanity check. */ 703 if (m == NULL) 704 panic("%s: NULL pointer was passed.\n", __func__); 705 706 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 707 printf("%s:\n", __func__); kdebug_mbuf(m)); 708 709 /* Set default. */ 710 spidx->ul_proto = IPSEC_ULPROTO_ANY; 711 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 712 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 713 714 nxt = -1; 715 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 716 if (off < 0 || m->m_pkthdr.len < off) 717 return; 718 719 switch (nxt) { 720 case IPPROTO_TCP: 721 spidx->ul_proto = nxt; 722 if (!needport) 723 break; 724 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 725 break; 726 m_copydata(m, off, sizeof(th), (caddr_t)&th); 727 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 728 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 729 break; 730 case IPPROTO_UDP: 731 spidx->ul_proto = nxt; 732 if (!needport) 733 break; 734 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 735 break; 736 m_copydata(m, off, sizeof(uh), (caddr_t)&uh); 737 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 738 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 739 break; 740 case IPPROTO_ICMPV6: 741 spidx->ul_proto = nxt; 742 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 743 break; 744 m_copydata(m, off, sizeof(ih), (caddr_t)&ih); 745 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 746 htons((uint16_t)ih.icmp6_type); 747 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 748 htons((uint16_t)ih.icmp6_code); 749 break; 750 default: 751 /* XXX Intermediate headers??? */ 752 spidx->ul_proto = nxt; 753 break; 754 } 755} 756 757/* Assumes that m is sane. */ 758static int 759ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 760{ 761 struct ip6_hdr *ip6 = NULL; 762 struct ip6_hdr ip6buf; 763 struct sockaddr_in6 *sin6; 764 765 if (m->m_len >= sizeof(*ip6)) 766 ip6 = mtod(m, struct ip6_hdr *); 767 else { 768 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf); 769 ip6 = &ip6buf; 770 } 771 772 sin6 = (struct sockaddr_in6 *)&spidx->src; 773 bzero(sin6, sizeof(*sin6)); 774 sin6->sin6_family = AF_INET6; 775 sin6->sin6_len = sizeof(struct sockaddr_in6); 776 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src)); 777 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 778 sin6->sin6_addr.s6_addr16[1] = 0; 779 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 780 } 781 spidx->prefs = sizeof(struct in6_addr) << 3; 782 783 sin6 = (struct sockaddr_in6 *)&spidx->dst; 784 bzero(sin6, sizeof(*sin6)); 785 sin6->sin6_family = AF_INET6; 786 sin6->sin6_len = sizeof(struct sockaddr_in6); 787 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst)); 788 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 789 sin6->sin6_addr.s6_addr16[1] = 0; 790 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 791 } 792 spidx->prefd = sizeof(struct in6_addr) << 3; 793 794 return (0); 795} 796#endif 797 798static void 799ipsec_delpcbpolicy(struct inpcbpolicy *p) 800{ 801 802 free(p, M_IPSEC_INPCB); 803} 804 805/* Initialize policy in PCB. */ 806int 807ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp) 808{ 809 struct inpcbpolicy *new; 810 811 /* Sanity check. */ 812 if (so == NULL || pcb_sp == NULL) 813 panic("%s: NULL pointer was passed.\n", __func__); 814 815 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy), 816 M_IPSEC_INPCB, M_NOWAIT|M_ZERO); 817 if (new == NULL) { 818 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 819 return (ENOBUFS); 820 } 821 822 new->priv = IPSEC_IS_PRIVILEGED_SO(so); 823 824 if ((new->sp_in = KEY_NEWSP()) == NULL) { 825 ipsec_delpcbpolicy(new); 826 return (ENOBUFS); 827 } 828 new->sp_in->state = IPSEC_SPSTATE_ALIVE; 829 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 830 831 if ((new->sp_out = KEY_NEWSP()) == NULL) { 832 KEY_FREESP(&new->sp_in); 833 ipsec_delpcbpolicy(new); 834 return (ENOBUFS); 835 } 836 new->sp_out->state = IPSEC_SPSTATE_ALIVE; 837 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 838 839 *pcb_sp = new; 840 841 return (0); 842} 843 844/* Copy old IPsec policy into new. */ 845int 846ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new) 847{ 848 struct secpolicy *sp; 849 850 sp = ipsec_deepcopy_policy(old->sp_in); 851 if (sp) { 852 KEY_FREESP(&new->sp_in); 853 new->sp_in = sp; 854 } else 855 return (ENOBUFS); 856 857 sp = ipsec_deepcopy_policy(old->sp_out); 858 if (sp) { 859 KEY_FREESP(&new->sp_out); 860 new->sp_out = sp; 861 } else 862 return (ENOBUFS); 863 864 new->priv = old->priv; 865 866 return (0); 867} 868 869struct ipsecrequest * 870ipsec_newisr(void) 871{ 872 struct ipsecrequest *p; 873 874 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO); 875 if (p != NULL) 876 IPSECREQUEST_LOCK_INIT(p); 877 return (p); 878} 879 880void 881ipsec_delisr(struct ipsecrequest *p) 882{ 883 884 IPSECREQUEST_LOCK_DESTROY(p); 885 free(p, M_IPSEC_SR); 886} 887 888/* Deep-copy a policy in PCB. */ 889static struct secpolicy * 890ipsec_deepcopy_policy(struct secpolicy *src) 891{ 892 struct ipsecrequest *newchain = NULL; 893 struct ipsecrequest *p; 894 struct ipsecrequest **q; 895 struct ipsecrequest *r; 896 struct secpolicy *dst; 897 898 if (src == NULL) 899 return (NULL); 900 dst = KEY_NEWSP(); 901 if (dst == NULL) 902 return (NULL); 903 904 /* 905 * Deep-copy IPsec request chain. This is required since struct 906 * ipsecrequest is not reference counted. 907 */ 908 q = &newchain; 909 for (p = src->req; p; p = p->next) { 910 *q = ipsec_newisr(); 911 if (*q == NULL) 912 goto fail; 913 (*q)->saidx.proto = p->saidx.proto; 914 (*q)->saidx.mode = p->saidx.mode; 915 (*q)->level = p->level; 916 (*q)->saidx.reqid = p->saidx.reqid; 917 918 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src)); 919 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst)); 920 921 (*q)->sp = dst; 922 923 q = &((*q)->next); 924 } 925 926 dst->req = newchain; 927 dst->state = src->state; 928 dst->policy = src->policy; 929 /* Do not touch the refcnt fields. */ 930 931 return (dst); 932 933fail: 934 for (p = newchain; p; p = r) { 935 r = p->next; 936 ipsec_delisr(p); 937 p = NULL; 938 } 939 return (NULL); 940} 941 942/* Set policy and IPsec request if present. */ 943static int 944ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname, 945 caddr_t request, size_t len, struct ucred *cred) 946{ 947 struct sadb_x_policy *xpl; 948 struct secpolicy *newsp = NULL; 949 int error; 950 951 /* Sanity check. */ 952 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL) 953 return (EINVAL); 954 if (len < sizeof(*xpl)) 955 return (EINVAL); 956 xpl = (struct sadb_x_policy *)request; 957 958 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 959 printf("%s: passed policy\n", __func__); 960 kdebug_sadb_x_policy((struct sadb_ext *)xpl)); 961 962 /* Check policy type. */ 963 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */ 964 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 965 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 966 return (EINVAL); 967 968 /* Check privileged socket. */ 969 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 970 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0); 971 if (error) 972 return (EACCES); 973 } 974 975 /* Allocating new SP entry. */ 976 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 977 return (error); 978 979 newsp->state = IPSEC_SPSTATE_ALIVE; 980 981 /* Clear old SP and set new SP. */ 982 KEY_FREESP(pcb_sp); 983 *pcb_sp = newsp; 984 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 985 printf("%s: new policy\n", __func__); 986 kdebug_secpolicy(newsp)); 987 988 return (0); 989} 990 991int 992ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request, 993 size_t len, struct ucred *cred) 994{ 995 struct sadb_x_policy *xpl; 996 struct secpolicy **pcb_sp; 997 998 /* Sanity check. */ 999 if (inp == NULL || request == NULL) 1000 return (EINVAL); 1001 if (len < sizeof(*xpl)) 1002 return (EINVAL); 1003 xpl = (struct sadb_x_policy *)request; 1004 1005 /* Select direction. */ 1006 switch (xpl->sadb_x_policy_dir) { 1007 case IPSEC_DIR_INBOUND: 1008 pcb_sp = &inp->inp_sp->sp_in; 1009 break; 1010 case IPSEC_DIR_OUTBOUND: 1011 pcb_sp = &inp->inp_sp->sp_out; 1012 break; 1013 default: 1014 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1015 xpl->sadb_x_policy_dir)); 1016 return (EINVAL); 1017 } 1018 1019 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred)); 1020} 1021 1022int 1023ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len, 1024 struct mbuf **mp) 1025{ 1026 struct sadb_x_policy *xpl; 1027 struct secpolicy *pcb_sp; 1028 1029 /* Sanity check. */ 1030 if (inp == NULL || request == NULL || mp == NULL) 1031 return (EINVAL); 1032 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 1033 if (len < sizeof(*xpl)) 1034 return (EINVAL); 1035 xpl = (struct sadb_x_policy *)request; 1036 1037 /* Select direction. */ 1038 switch (xpl->sadb_x_policy_dir) { 1039 case IPSEC_DIR_INBOUND: 1040 pcb_sp = inp->inp_sp->sp_in; 1041 break; 1042 case IPSEC_DIR_OUTBOUND: 1043 pcb_sp = inp->inp_sp->sp_out; 1044 break; 1045 default: 1046 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1047 xpl->sadb_x_policy_dir)); 1048 return (EINVAL); 1049 } 1050 1051 /* Sanity check. Should be an IPSEC_ASSERT. */ 1052 if (pcb_sp == NULL) 1053 return (EINVAL); 1054 1055 *mp = key_sp2msg(pcb_sp); 1056 if (!*mp) { 1057 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 1058 return (ENOBUFS); 1059 } 1060 1061 (*mp)->m_type = MT_DATA; 1062 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1063 printf("%s:\n", __func__); kdebug_mbuf(*mp)); 1064 1065 return (0); 1066} 1067 1068/* Delete policy in PCB. */ 1069int 1070ipsec_delete_pcbpolicy(struct inpcb *inp) 1071{ 1072 IPSEC_ASSERT(inp != NULL, ("null inp")); 1073 1074 if (inp->inp_sp == NULL) 1075 return (0); 1076 1077 if (inp->inp_sp->sp_in != NULL) 1078 KEY_FREESP(&inp->inp_sp->sp_in); 1079 1080 if (inp->inp_sp->sp_out != NULL) 1081 KEY_FREESP(&inp->inp_sp->sp_out); 1082 1083 ipsec_delpcbpolicy(inp->inp_sp); 1084 inp->inp_sp = NULL; 1085 1086 return (0); 1087} 1088 1089/* 1090 * Return current level. 1091 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1092 */ 1093u_int 1094ipsec_get_reqlevel(struct ipsecrequest *isr) 1095{ 1096 u_int level = 0; 1097 u_int esp_trans_deflev, esp_net_deflev; 1098 u_int ah_trans_deflev, ah_net_deflev; 1099 1100 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument")); 1101 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1102 ("af family mismatch, src %u, dst %u", 1103 isr->sp->spidx.src.sa.sa_family, 1104 isr->sp->spidx.dst.sa.sa_family)); 1105 1106/* XXX Note that we have ipseclog() expanded here - code sync issue. */ 1107#define IPSEC_CHECK_DEFAULT(lev) \ 1108 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1109 && (lev) != IPSEC_LEVEL_UNIQUE) \ 1110 ? (V_ipsec_debug \ 1111 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\ 1112 (lev), IPSEC_LEVEL_REQUIRE) \ 1113 : 0), \ 1114 (lev) = IPSEC_LEVEL_REQUIRE, \ 1115 (lev) \ 1116 : (lev)) 1117 1118 /* Set default level. */ 1119 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1120#ifdef INET 1121 case AF_INET: 1122 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev); 1123 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev); 1124 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev); 1125 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev); 1126 break; 1127#endif 1128#ifdef INET6 1129 case AF_INET6: 1130 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev); 1131 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev); 1132 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev); 1133 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev); 1134 break; 1135#endif /* INET6 */ 1136 default: 1137 panic("%s: unknown af %u", 1138 __func__, isr->sp->spidx.src.sa.sa_family); 1139 } 1140 1141#undef IPSEC_CHECK_DEFAULT 1142 1143 /* Set level. */ 1144 switch (isr->level) { 1145 case IPSEC_LEVEL_DEFAULT: 1146 switch (isr->saidx.proto) { 1147 case IPPROTO_ESP: 1148 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1149 level = esp_net_deflev; 1150 else 1151 level = esp_trans_deflev; 1152 break; 1153 case IPPROTO_AH: 1154 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1155 level = ah_net_deflev; 1156 else 1157 level = ah_trans_deflev; 1158 break; 1159 case IPPROTO_IPCOMP: 1160 /* 1161 * We don't really care, as IPcomp document says that 1162 * we shouldn't compress small packets. 1163 */ 1164 level = IPSEC_LEVEL_USE; 1165 break; 1166 default: 1167 panic("%s: Illegal protocol defined %u\n", __func__, 1168 isr->saidx.proto); 1169 } 1170 break; 1171 1172 case IPSEC_LEVEL_USE: 1173 case IPSEC_LEVEL_REQUIRE: 1174 level = isr->level; 1175 break; 1176 case IPSEC_LEVEL_UNIQUE: 1177 level = IPSEC_LEVEL_REQUIRE; 1178 break; 1179 1180 default: 1181 panic("%s: Illegal IPsec level %u\n", __func__, isr->level); 1182 } 1183 1184 return (level); 1185} 1186 1187/* 1188 * Check security policy requirements against the actual 1189 * packet contents. Return one if the packet should be 1190 * reject as "invalid"; otherwiser return zero to have the 1191 * packet treated as "valid". 1192 * 1193 * OUT: 1194 * 0: valid 1195 * 1: invalid 1196 */ 1197int 1198ipsec_in_reject(struct secpolicy *sp, struct mbuf *m) 1199{ 1200 struct ipsecrequest *isr; 1201 int need_auth; 1202 1203 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1204 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1205 1206 /* Check policy. */ 1207 switch (sp->policy) { 1208 case IPSEC_POLICY_DISCARD: 1209 return (1); 1210 case IPSEC_POLICY_BYPASS: 1211 case IPSEC_POLICY_NONE: 1212 return (0); 1213 } 1214 1215 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1216 ("invalid policy %u", sp->policy)); 1217 1218 /* XXX Should compare policy against IPsec header history. */ 1219 1220 need_auth = 0; 1221 for (isr = sp->req; isr != NULL; isr = isr->next) { 1222 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1223 continue; 1224 switch (isr->saidx.proto) { 1225 case IPPROTO_ESP: 1226 if ((m->m_flags & M_DECRYPTED) == 0) { 1227 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1228 printf("%s: ESP m_flags:%x\n", __func__, 1229 m->m_flags)); 1230 return (1); 1231 } 1232 1233 if (!need_auth && 1234 isr->sav != NULL && 1235 isr->sav->tdb_authalgxform != NULL && 1236 (m->m_flags & M_AUTHIPDGM) == 0) { 1237 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1238 printf("%s: ESP/AH m_flags:%x\n", __func__, 1239 m->m_flags)); 1240 return (1); 1241 } 1242 break; 1243 case IPPROTO_AH: 1244 need_auth = 1; 1245 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1246 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1247 printf("%s: AH m_flags:%x\n", __func__, 1248 m->m_flags)); 1249 return (1); 1250 } 1251 break; 1252 case IPPROTO_IPCOMP: 1253 /* 1254 * We don't really care, as IPcomp document 1255 * says that we shouldn't compress small 1256 * packets. IPComp policy should always be 1257 * treated as being in "use" level. 1258 */ 1259 break; 1260 } 1261 } 1262 return (0); /* Valid. */ 1263} 1264 1265static int 1266ipsec46_in_reject(struct mbuf *m, struct inpcb *inp) 1267{ 1268 struct secpolicy *sp; 1269 int error; 1270 int result; 1271 1272 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1273 1274 /* 1275 * Get SP for this packet. 1276 * When we are called from ip_forward(), we call 1277 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1278 */ 1279 if (inp == NULL) 1280 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1281 else 1282 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error); 1283 1284 if (sp != NULL) { 1285 result = ipsec_in_reject(sp, m); 1286 KEY_FREESP(&sp); 1287 } else { 1288 result = 0; /* XXX Should be panic? 1289 * -> No, there may be error. */ 1290 } 1291 return (result); 1292} 1293 1294/* 1295 * Check AH/ESP integrity. 1296 * This function is called from tcp_input(), udp_input(), 1297 * and {ah,esp}4_input for tunnel mode. 1298 */ 1299int 1300ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1301{ 1302 int result; 1303 1304 result = ipsec46_in_reject(m, inp); 1305 if (result) 1306 IPSECSTAT_INC(ips_in_polvio); 1307 1308 return (result); 1309} 1310 1311#ifdef INET6 1312/* 1313 * Check AH/ESP integrity. 1314 * This function is called from tcp6_input(), udp6_input(), 1315 * and {ah,esp}6_input for tunnel mode. 1316 */ 1317int 1318ipsec6_in_reject(struct mbuf *m, struct inpcb *inp) 1319{ 1320 int result; 1321 1322 result = ipsec46_in_reject(m, inp); 1323 if (result) 1324 IPSEC6STAT_INC(ips_in_polvio); 1325 1326 return (result); 1327} 1328#endif 1329 1330/* 1331 * Compute the byte size to be occupied by IPsec header. 1332 * In case it is tunnelled, it includes the size of outer IP header. 1333 * NOTE: SP passed is freed in this function. 1334 */ 1335static size_t 1336ipsec_hdrsiz_internal(struct secpolicy *sp) 1337{ 1338 struct ipsecrequest *isr; 1339 size_t size; 1340 1341 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1342 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1343 1344 switch (sp->policy) { 1345 case IPSEC_POLICY_DISCARD: 1346 case IPSEC_POLICY_BYPASS: 1347 case IPSEC_POLICY_NONE: 1348 return (0); 1349 } 1350 1351 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1352 ("invalid policy %u", sp->policy)); 1353 1354 size = 0; 1355 for (isr = sp->req; isr != NULL; isr = isr->next) { 1356 size_t clen = 0; 1357 1358 switch (isr->saidx.proto) { 1359 case IPPROTO_ESP: 1360 clen = esp_hdrsiz(isr->sav); 1361 break; 1362 case IPPROTO_AH: 1363 clen = ah_hdrsiz(isr->sav); 1364 break; 1365 case IPPROTO_IPCOMP: 1366 clen = sizeof(struct ipcomp); 1367 break; 1368 } 1369 1370 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1371 switch (isr->saidx.dst.sa.sa_family) { 1372 case AF_INET: 1373 clen += sizeof(struct ip); 1374 break; 1375#ifdef INET6 1376 case AF_INET6: 1377 clen += sizeof(struct ip6_hdr); 1378 break; 1379#endif 1380 default: 1381 ipseclog((LOG_ERR, "%s: unknown AF %d in " 1382 "IPsec tunnel SA\n", __func__, 1383 ((struct sockaddr *)&isr->saidx.dst)->sa_family)); 1384 break; 1385 } 1386 } 1387 size += clen; 1388 } 1389 1390 return (size); 1391} 1392 1393/* 1394 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(), 1395 * disabled ip6_ipsec_mtu() and ip6_forward(). 1396 */ 1397size_t 1398ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1399{ 1400 struct secpolicy *sp; 1401 int error; 1402 size_t size; 1403 1404 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1405 1406 /* Get SP for this packet. 1407 * When we are called from ip_forward(), we call 1408 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1409 */ 1410 if (inp == NULL) 1411 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1412 else 1413 sp = ipsec_getpolicybysock(m, dir, inp, &error); 1414 1415 if (sp != NULL) { 1416 size = ipsec_hdrsiz_internal(sp); 1417 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1418 printf("%s: size:%lu.\n", __func__, 1419 (unsigned long)size)); 1420 1421 KEY_FREESP(&sp); 1422 } else { 1423 size = 0; /* XXX Should be panic? 1424 * -> No, we are called w/o knowing if 1425 * IPsec processing is needed. */ 1426 } 1427 return (size); 1428} 1429 1430/* 1431 * Check the variable replay window. 1432 * ipsec_chkreplay() performs replay check before ICV verification. 1433 * ipsec_updatereplay() updates replay bitmap. This must be called after 1434 * ICV verification (it also performs replay check, which is usually done 1435 * beforehand). 1436 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1437 * 1438 * Based on RFC 2401. 1439 */ 1440int 1441ipsec_chkreplay(u_int32_t seq, struct secasvar *sav) 1442{ 1443 const struct secreplay *replay; 1444 u_int32_t diff; 1445 int fr; 1446 u_int32_t wsizeb; /* Constant: bits of window size. */ 1447 int frlast; /* Constant: last frame. */ 1448 1449 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1450 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1451 1452 replay = sav->replay; 1453 1454 if (replay->wsize == 0) 1455 return (1); /* No need to check replay. */ 1456 1457 /* Constant. */ 1458 frlast = replay->wsize - 1; 1459 wsizeb = replay->wsize << 3; 1460 1461 /* Sequence number of 0 is invalid. */ 1462 if (seq == 0) 1463 return (0); 1464 1465 /* First time is always okay. */ 1466 if (replay->count == 0) 1467 return (1); 1468 1469 if (seq > replay->lastseq) { 1470 /* Larger sequences are okay. */ 1471 return (1); 1472 } else { 1473 /* seq is equal or less than lastseq. */ 1474 diff = replay->lastseq - seq; 1475 1476 /* Over range to check, i.e. too old or wrapped. */ 1477 if (diff >= wsizeb) 1478 return (0); 1479 1480 fr = frlast - diff / 8; 1481 1482 /* This packet already seen? */ 1483 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1484 return (0); 1485 1486 /* Out of order but good. */ 1487 return (1); 1488 } 1489} 1490 1491/* 1492 * Check replay counter whether to update or not. 1493 * OUT: 0: OK 1494 * 1: NG 1495 */ 1496int 1497ipsec_updatereplay(u_int32_t seq, struct secasvar *sav) 1498{ 1499 struct secreplay *replay; 1500 u_int32_t diff; 1501 int fr; 1502 u_int32_t wsizeb; /* Constant: bits of window size. */ 1503 int frlast; /* Constant: last frame. */ 1504 1505 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1506 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1507 1508 replay = sav->replay; 1509 1510 if (replay->wsize == 0) 1511 goto ok; /* No need to check replay. */ 1512 1513 /* Constant. */ 1514 frlast = replay->wsize - 1; 1515 wsizeb = replay->wsize << 3; 1516 1517 /* Sequence number of 0 is invalid. */ 1518 if (seq == 0) 1519 return (1); 1520 1521 /* First time. */ 1522 if (replay->count == 0) { 1523 replay->lastseq = seq; 1524 bzero(replay->bitmap, replay->wsize); 1525 (replay->bitmap)[frlast] = 1; 1526 goto ok; 1527 } 1528 1529 if (seq > replay->lastseq) { 1530 /* seq is larger than lastseq. */ 1531 diff = seq - replay->lastseq; 1532 1533 /* New larger sequence number. */ 1534 if (diff < wsizeb) { 1535 /* In window. */ 1536 /* Set bit for this packet. */ 1537 vshiftl(replay->bitmap, diff, replay->wsize); 1538 (replay->bitmap)[frlast] |= 1; 1539 } else { 1540 /* This packet has a "way larger". */ 1541 bzero(replay->bitmap, replay->wsize); 1542 (replay->bitmap)[frlast] = 1; 1543 } 1544 replay->lastseq = seq; 1545 1546 /* Larger is good. */ 1547 } else { 1548 /* seq is equal or less than lastseq. */ 1549 diff = replay->lastseq - seq; 1550 1551 /* Over range to check, i.e. too old or wrapped. */ 1552 if (diff >= wsizeb) 1553 return (1); 1554 1555 fr = frlast - diff / 8; 1556 1557 /* This packet already seen? */ 1558 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1559 return (1); 1560 1561 /* Mark as seen. */ 1562 (replay->bitmap)[fr] |= (1 << (diff % 8)); 1563 1564 /* Out of order but good. */ 1565 } 1566 1567ok: 1568 if (replay->count == ~0) { 1569 1570 /* Set overflow flag. */ 1571 replay->overflow++; 1572 1573 /* Don't increment, no more packets accepted. */ 1574 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 1575 return (1); 1576 1577 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1578 __func__, replay->overflow, ipsec_logsastr(sav))); 1579 } 1580 1581 replay->count++; 1582 1583 return (0); 1584} 1585 1586/* 1587 * Shift variable length buffer to left. 1588 * IN: bitmap: pointer to the buffer 1589 * nbit: the number of to shift. 1590 * wsize: buffer size (bytes). 1591 */ 1592static void 1593vshiftl(unsigned char *bitmap, int nbit, int wsize) 1594{ 1595 int s, j, i; 1596 unsigned char over; 1597 1598 for (j = 0; j < nbit; j += 8) { 1599 s = (nbit - j < 8) ? (nbit - j): 8; 1600 bitmap[0] <<= s; 1601 for (i = 1; i < wsize; i++) { 1602 over = (bitmap[i] >> (8 - s)); 1603 bitmap[i] <<= s; 1604 bitmap[i-1] |= over; 1605 } 1606 } 1607} 1608 1609#ifdef INET 1610/* Return a printable string for the IPv4 address. */ 1611static char * 1612inet_ntoa4(struct in_addr ina) 1613{ 1614 static char buf[4][4 * sizeof "123" + 4]; 1615 unsigned char *ucp = (unsigned char *) &ina; 1616 static int i = 3; 1617 1618 /* XXX-BZ Returns static buffer. */ 1619 i = (i + 1) % 4; 1620 sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff, 1621 ucp[2] & 0xff, ucp[3] & 0xff); 1622 return (buf[i]); 1623} 1624#endif 1625 1626/* Return a printable string for the address. */ 1627char * 1628ipsec_address(union sockaddr_union* sa) 1629{ 1630#ifdef INET6 1631 char ip6buf[INET6_ADDRSTRLEN]; 1632#endif 1633 1634 switch (sa->sa.sa_family) { 1635#ifdef INET 1636 case AF_INET: 1637 return (inet_ntoa4(sa->sin.sin_addr)); 1638#endif /* INET */ 1639#ifdef INET6 1640 case AF_INET6: 1641 return (ip6_sprintf(ip6buf, &sa->sin6.sin6_addr)); 1642#endif /* INET6 */ 1643 default: 1644 return ("(unknown address family)"); 1645 } 1646} 1647 1648const char * 1649ipsec_logsastr(struct secasvar *sav) 1650{ 1651 static char buf[256]; 1652 char *p; 1653 struct secasindex *saidx = &sav->sah->saidx; 1654 1655 IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 1656 ("address family mismatch")); 1657 1658 p = buf; 1659 snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi)); 1660 while (p && *p) 1661 p++; 1662 /* NB: only use ipsec_address on one address at a time. */ 1663 snprintf(p, sizeof (buf) - (p - buf), "src=%s ", 1664 ipsec_address(&saidx->src)); 1665 while (p && *p) 1666 p++; 1667 snprintf(p, sizeof (buf) - (p - buf), "dst=%s)", 1668 ipsec_address(&saidx->dst)); 1669 1670 return (buf); 1671} 1672 1673void 1674ipsec_dumpmbuf(struct mbuf *m) 1675{ 1676 int totlen; 1677 int i; 1678 u_char *p; 1679 1680 totlen = 0; 1681 printf("---\n"); 1682 while (m) { 1683 p = mtod(m, u_char *); 1684 for (i = 0; i < m->m_len; i++) { 1685 printf("%02x ", p[i]); 1686 totlen++; 1687 if (totlen % 16 == 0) 1688 printf("\n"); 1689 } 1690 m = m->m_next; 1691 } 1692 if (totlen % 16 != 0) 1693 printf("\n"); 1694 printf("---\n"); 1695} 1696 1697static void 1698ipsec_init(const void *unused __unused) 1699{ 1700 1701 SECPOLICY_LOCK_INIT(&V_ip4_def_policy); 1702 V_ip4_def_policy.refcnt = 1; /* NB: disallow free. */ 1703} 1704VNET_SYSINIT(ipsec_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, ipsec_init, 1705 NULL); 1706 1707 1708/* XXX This stuff doesn't belong here... */ 1709 1710static struct xformsw* xforms = NULL; 1711 1712/* 1713 * Register a transform; typically at system startup. 1714 */ 1715void 1716xform_register(struct xformsw* xsp) 1717{ 1718 1719 xsp->xf_next = xforms; 1720 xforms = xsp; 1721} 1722 1723/* 1724 * Initialize transform support in an sav. 1725 */ 1726int 1727xform_init(struct secasvar *sav, int xftype) 1728{ 1729 struct xformsw *xsp; 1730 1731 if (sav->tdb_xform != NULL) /* Previously initialized. */ 1732 return (0); 1733 for (xsp = xforms; xsp; xsp = xsp->xf_next) 1734 if (xsp->xf_type == xftype) 1735 return ((*xsp->xf_init)(sav, xsp)); 1736 return (EINVAL); 1737} 1738