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 101 VNET_DEFINE(int, ipsec_debug) = 1; 102 #else 103 VNET_DEFINE(int, ipsec_debug) = 0; 104 #endif 105 106 /* NB: name changed so netstat doesn't use it. */ 107 VNET_DEFINE(struct ipsecstat, ipsec4stat); 108 VNET_DEFINE(int, ip4_ah_offsetmask) = 0; /* maybe IP_DF? */ 109 /* DF bit on encap. 0: clear 1: set 2: copy */ 110 VNET_DEFINE(int, ip4_ipsec_dfbit) = 0; 111 VNET_DEFINE(int, ip4_esp_trans_deflev) = IPSEC_LEVEL_USE; 112 VNET_DEFINE(int, ip4_esp_net_deflev) = IPSEC_LEVEL_USE; 113 VNET_DEFINE(int, ip4_ah_trans_deflev) = IPSEC_LEVEL_USE; 114 VNET_DEFINE(int, ip4_ah_net_deflev) = IPSEC_LEVEL_USE; 115 VNET_DEFINE(struct secpolicy, ip4_def_policy); 116 /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 117 VNET_DEFINE(int, ip4_ipsec_ecn) = 0; 118 VNET_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 */ 127 VNET_DEFINE(int, crypto_support) = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE; 128 129 FEATURE(ipsec, "Internet Protocol Security (IPsec)"); 130 #ifdef IPSEC_NAT_T 131 FEATURE(ipsec_natt, "UDP Encapsulation of IPsec ESP Packets ('NAT-T')"); 132 #endif 133 134 SYSCTL_DECL(_net_inet_ipsec); 135 136 /* net.inet.ipsec */ 137 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy, 138 CTLFLAG_RW, &VNET_NAME(ip4_def_policy).policy, 0, 139 "IPsec default policy."); 140 SYSCTL_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"); 143 SYSCTL_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."); 146 SYSCTL_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."); 149 SYSCTL_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."); 152 SYSCTL_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."); 155 SYSCTL_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."); 158 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit, 159 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_dfbit), 0, 160 "Do not fragment bit on encap."); 161 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn, 162 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_ecn), 0, 163 "Explicit Congestion Notification handling."); 164 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEBUG, debug, 165 CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0, 166 "Enable IPsec debugging output when set."); 167 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, crypto_support, 168 CTLFLAG_RW, &VNET_NAME(crypto_support), 0, 169 "Crypto driver selection."); 170 SYSCTL_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 */ 179 VNET_DEFINE(int, ipsec_replay) = 0; 180 SYSCTL_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 */ 187 VNET_DEFINE(int, ipsec_integrity) = 0; 188 SYSCTL_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 194 VNET_DEFINE(struct ipsecstat, ipsec6stat); 195 VNET_DEFINE(int, ip6_esp_trans_deflev) = IPSEC_LEVEL_USE; 196 VNET_DEFINE(int, ip6_esp_net_deflev) = IPSEC_LEVEL_USE; 197 VNET_DEFINE(int, ip6_ah_trans_deflev) = IPSEC_LEVEL_USE; 198 VNET_DEFINE(int, ip6_ah_net_deflev) = IPSEC_LEVEL_USE; 199 VNET_DEFINE(int, ip6_ipsec_ecn) = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 200 201 SYSCTL_DECL(_net_inet6_ipsec6); 202 203 /* net.inet6.ipsec6 */ 204 #ifdef COMPAT_KAME 205 SYSCTL_OID(_net_inet6_ipsec6, IPSECCTL_STATS, stats, CTLFLAG_RD, 206 0, 0, compat_ipsecstats_sysctl, "S", "IPsec IPv6 statistics."); 207 #endif /* COMPAT_KAME */ 208 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy, CTLFLAG_RW, 209 &VNET_NAME(ip4_def_policy).policy, 0, 210 "IPsec default policy."); 211 SYSCTL_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."); 214 SYSCTL_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."); 217 SYSCTL_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."); 220 SYSCTL_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."); 223 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_ECN, 224 ecn, CTLFLAG_RW, &VNET_NAME(ip6_ipsec_ecn), 0, 225 "Explicit Congestion Notification handling."); 226 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEBUG, debug, CTLFLAG_RW, 227 &VNET_NAME(ipsec_debug), 0, 228 "Enable IPsec debugging output when set."); 229 SYSCTL_VNET_STRUCT(_net_inet6_ipsec6, IPSECCTL_STATS, 230 ipsecstats, CTLFLAG_RD, &VNET_NAME(ipsec6stat), ipsecstat, 231 "IPsec IPv6 statistics."); 232 #endif /* INET6 */ 233 234 static int ipsec_setspidx_inpcb __P((struct mbuf *, struct inpcb *)); 235 static int ipsec_setspidx __P((struct mbuf *, struct secpolicyindex *, int)); 236 static void ipsec4_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 237 static int ipsec4_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 238 #ifdef INET6 239 static void ipsec6_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 240 static int ipsec6_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 241 #endif 242 static void ipsec_delpcbpolicy __P((struct inpcbpolicy *)); 243 static struct secpolicy *ipsec_deepcopy_policy __P((struct secpolicy *src)); 244 static void vshiftl __P((unsigned char *, int, int)); 245 246 MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy"); 247 248 /* 249 * Return a held reference to the default SP. 250 */ 251 static struct secpolicy * 252 key_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 */ 288 struct secpolicy * 289 ipsec_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 */ 316 static struct secpolicy * 317 ipsec_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 */ 413 struct secpolicy * 414 ipsec_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 } 443 444 struct secpolicy * 445 ipsec4_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 } 486 487 static int 488 ipsec_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 */ 516 static int 517 ipsec_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 #ifdef _IP_VHL 557 v = _IP_VHL_V(ip->ip_vhl); 558 #else 559 v = ip->ip_v; 560 #endif 561 switch (v) { 562 case 4: 563 error = ipsec4_setspidx_ipaddr(m, spidx); 564 if (error) 565 return (error); 566 ipsec4_get_ulp(m, spidx, needport); 567 return (0); 568 #ifdef INET6 569 case 6: 570 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 571 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 572 printf("%s: pkthdr len(%d) too small (v6), " 573 "ignored\n", __func__, m->m_pkthdr.len)); 574 return (EINVAL); 575 } 576 error = ipsec6_setspidx_ipaddr(m, spidx); 577 if (error) 578 return (error); 579 ipsec6_get_ulp(m, spidx, needport); 580 return (0); 581 #endif 582 default: 583 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 584 printf("%s: " "unknown IP version %u, ignored.\n", 585 __func__, v)); 586 return (EINVAL); 587 } 588 } 589 590 static void 591 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 592 { 593 u_int8_t nxt; 594 int off; 595 596 /* Sanity check. */ 597 IPSEC_ASSERT(m != NULL, ("null mbuf")); 598 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short")); 599 600 if (m->m_len >= sizeof (struct ip)) { 601 struct ip *ip = mtod(m, struct ip *); 602 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 603 goto done; 604 #ifdef _IP_VHL 605 off = _IP_VHL_HL(ip->ip_vhl) << 2; 606 #else 607 off = ip->ip_hl << 2; 608 #endif 609 nxt = ip->ip_p; 610 } else { 611 struct ip ih; 612 613 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih); 614 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 615 goto done; 616 #ifdef _IP_VHL 617 off = _IP_VHL_HL(ih.ip_vhl) << 2; 618 #else 619 off = ih.ip_hl << 2; 620 #endif 621 nxt = ih.ip_p; 622 } 623 624 while (off < m->m_pkthdr.len) { 625 struct ip6_ext ip6e; 626 struct tcphdr th; 627 struct udphdr uh; 628 629 switch (nxt) { 630 case IPPROTO_TCP: 631 spidx->ul_proto = nxt; 632 if (!needport) 633 goto done_proto; 634 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 635 goto done; 636 m_copydata(m, off, sizeof (th), (caddr_t) &th); 637 spidx->src.sin.sin_port = th.th_sport; 638 spidx->dst.sin.sin_port = th.th_dport; 639 return; 640 case IPPROTO_UDP: 641 spidx->ul_proto = nxt; 642 if (!needport) 643 goto done_proto; 644 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 645 goto done; 646 m_copydata(m, off, sizeof (uh), (caddr_t) &uh); 647 spidx->src.sin.sin_port = uh.uh_sport; 648 spidx->dst.sin.sin_port = uh.uh_dport; 649 return; 650 case IPPROTO_AH: 651 if (off + sizeof(ip6e) > m->m_pkthdr.len) 652 goto done; 653 /* XXX Sigh, this works but is totally bogus. */ 654 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e); 655 off += (ip6e.ip6e_len + 2) << 2; 656 nxt = ip6e.ip6e_nxt; 657 break; 658 case IPPROTO_ICMP: 659 default: 660 /* XXX Intermediate headers??? */ 661 spidx->ul_proto = nxt; 662 goto done_proto; 663 } 664 } 665 done: 666 spidx->ul_proto = IPSEC_ULPROTO_ANY; 667 done_proto: 668 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 669 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 670 } 671 672 /* Assumes that m is sane. */ 673 static int 674 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 675 { 676 static const struct sockaddr_in template = { 677 sizeof (struct sockaddr_in), 678 AF_INET, 679 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 680 }; 681 682 spidx->src.sin = template; 683 spidx->dst.sin = template; 684 685 if (m->m_len < sizeof (struct ip)) { 686 m_copydata(m, offsetof(struct ip, ip_src), 687 sizeof (struct in_addr), 688 (caddr_t) &spidx->src.sin.sin_addr); 689 m_copydata(m, offsetof(struct ip, ip_dst), 690 sizeof (struct in_addr), 691 (caddr_t) &spidx->dst.sin.sin_addr); 692 } else { 693 struct ip *ip = mtod(m, struct ip *); 694 spidx->src.sin.sin_addr = ip->ip_src; 695 spidx->dst.sin.sin_addr = ip->ip_dst; 696 } 697 698 spidx->prefs = sizeof(struct in_addr) << 3; 699 spidx->prefd = sizeof(struct in_addr) << 3; 700 701 return (0); 702 } 703 704 #ifdef INET6 705 static void 706 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 707 { 708 int off, nxt; 709 struct tcphdr th; 710 struct udphdr uh; 711 struct icmp6_hdr ih; 712 713 /* Sanity check. */ 714 if (m == NULL) 715 panic("%s: NULL pointer was passed.\n", __func__); 716 717 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 718 printf("%s:\n", __func__); kdebug_mbuf(m)); 719 720 /* Set default. */ 721 spidx->ul_proto = IPSEC_ULPROTO_ANY; 722 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 723 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 724 725 nxt = -1; 726 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 727 if (off < 0 || m->m_pkthdr.len < off) 728 return; 729 730 switch (nxt) { 731 case IPPROTO_TCP: 732 spidx->ul_proto = nxt; 733 if (!needport) 734 break; 735 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 736 break; 737 m_copydata(m, off, sizeof(th), (caddr_t)&th); 738 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 739 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 740 break; 741 case IPPROTO_UDP: 742 spidx->ul_proto = nxt; 743 if (!needport) 744 break; 745 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 746 break; 747 m_copydata(m, off, sizeof(uh), (caddr_t)&uh); 748 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 749 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 750 break; 751 case IPPROTO_ICMPV6: 752 spidx->ul_proto = nxt; 753 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 754 break; 755 m_copydata(m, off, sizeof(ih), (caddr_t)&ih); 756 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 757 htons((uint16_t)ih.icmp6_type); 758 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 759 htons((uint16_t)ih.icmp6_code); 760 break; 761 default: 762 /* XXX Intermediate headers??? */ 763 spidx->ul_proto = nxt; 764 break; 765 } 766 } 767 768 /* Assumes that m is sane. */ 769 static int 770 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 771 { 772 struct ip6_hdr *ip6 = NULL; 773 struct ip6_hdr ip6buf; 774 struct sockaddr_in6 *sin6; 775 776 if (m->m_len >= sizeof(*ip6)) 777 ip6 = mtod(m, struct ip6_hdr *); 778 else { 779 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf); 780 ip6 = &ip6buf; 781 } 782 783 sin6 = (struct sockaddr_in6 *)&spidx->src; 784 bzero(sin6, sizeof(*sin6)); 785 sin6->sin6_family = AF_INET6; 786 sin6->sin6_len = sizeof(struct sockaddr_in6); 787 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src)); 788 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 789 sin6->sin6_addr.s6_addr16[1] = 0; 790 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 791 } 792 spidx->prefs = sizeof(struct in6_addr) << 3; 793 794 sin6 = (struct sockaddr_in6 *)&spidx->dst; 795 bzero(sin6, sizeof(*sin6)); 796 sin6->sin6_family = AF_INET6; 797 sin6->sin6_len = sizeof(struct sockaddr_in6); 798 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst)); 799 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 800 sin6->sin6_addr.s6_addr16[1] = 0; 801 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 802 } 803 spidx->prefd = sizeof(struct in6_addr) << 3; 804 805 return (0); 806 } 807 #endif 808 809 static void 810 ipsec_delpcbpolicy(struct inpcbpolicy *p) 811 { 812 813 free(p, M_IPSEC_INPCB); 814 } 815 816 /* Initialize policy in PCB. */ 817 int 818 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp) 819 { 820 struct inpcbpolicy *new; 821 822 /* Sanity check. */ 823 if (so == NULL || pcb_sp == NULL) 824 panic("%s: NULL pointer was passed.\n", __func__); 825 826 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy), 827 M_IPSEC_INPCB, M_NOWAIT|M_ZERO); 828 if (new == NULL) { 829 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 830 return (ENOBUFS); 831 } 832 833 new->priv = IPSEC_IS_PRIVILEGED_SO(so); 834 835 if ((new->sp_in = KEY_NEWSP()) == NULL) { 836 ipsec_delpcbpolicy(new); 837 return (ENOBUFS); 838 } 839 new->sp_in->state = IPSEC_SPSTATE_ALIVE; 840 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 841 842 if ((new->sp_out = KEY_NEWSP()) == NULL) { 843 KEY_FREESP(&new->sp_in); 844 ipsec_delpcbpolicy(new); 845 return (ENOBUFS); 846 } 847 new->sp_out->state = IPSEC_SPSTATE_ALIVE; 848 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 849 850 *pcb_sp = new; 851 852 return (0); 853 } 854 855 /* Copy old IPsec policy into new. */ 856 int 857 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new) 858 { 859 struct secpolicy *sp; 860 861 sp = ipsec_deepcopy_policy(old->sp_in); 862 if (sp) { 863 KEY_FREESP(&new->sp_in); 864 new->sp_in = sp; 865 } else 866 return (ENOBUFS); 867 868 sp = ipsec_deepcopy_policy(old->sp_out); 869 if (sp) { 870 KEY_FREESP(&new->sp_out); 871 new->sp_out = sp; 872 } else 873 return (ENOBUFS); 874 875 new->priv = old->priv; 876 877 return (0); 878 } 879 880 struct ipsecrequest * 881 ipsec_newisr(void) 882 { 883 struct ipsecrequest *p; 884 885 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO); 886 if (p != NULL) 887 IPSECREQUEST_LOCK_INIT(p); 888 return (p); 889 } 890 891 void 892 ipsec_delisr(struct ipsecrequest *p) 893 { 894 895 IPSECREQUEST_LOCK_DESTROY(p); 896 free(p, M_IPSEC_SR); 897 } 898 899 /* Deep-copy a policy in PCB. */ 900 static struct secpolicy * 901 ipsec_deepcopy_policy(struct secpolicy *src) 902 { 903 struct ipsecrequest *newchain = NULL; 904 struct ipsecrequest *p; 905 struct ipsecrequest **q; 906 struct ipsecrequest *r; 907 struct secpolicy *dst; 908 909 if (src == NULL) 910 return (NULL); 911 dst = KEY_NEWSP(); 912 if (dst == NULL) 913 return (NULL); 914 915 /* 916 * Deep-copy IPsec request chain. This is required since struct 917 * ipsecrequest is not reference counted. 918 */ 919 q = &newchain; 920 for (p = src->req; p; p = p->next) { 921 *q = ipsec_newisr(); 922 if (*q == NULL) 923 goto fail; 924 (*q)->saidx.proto = p->saidx.proto; 925 (*q)->saidx.mode = p->saidx.mode; 926 (*q)->level = p->level; 927 (*q)->saidx.reqid = p->saidx.reqid; 928 929 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src)); 930 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst)); 931 932 (*q)->sp = dst; 933 934 q = &((*q)->next); 935 } 936 937 dst->req = newchain; 938 dst->state = src->state; 939 dst->policy = src->policy; 940 /* Do not touch the refcnt fields. */ 941 942 return (dst); 943 944 fail: 945 for (p = newchain; p; p = r) { 946 r = p->next; 947 ipsec_delisr(p); 948 p = NULL; 949 } 950 return (NULL); 951 } 952 953 /* Set policy and IPsec request if present. */ 954 static int 955 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname, 956 caddr_t request, size_t len, struct ucred *cred) 957 { 958 struct sadb_x_policy *xpl; 959 struct secpolicy *newsp = NULL; 960 int error; 961 962 /* Sanity check. */ 963 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL) 964 return (EINVAL); 965 if (len < sizeof(*xpl)) 966 return (EINVAL); 967 xpl = (struct sadb_x_policy *)request; 968 969 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 970 printf("%s: passed policy\n", __func__); 971 kdebug_sadb_x_policy((struct sadb_ext *)xpl)); 972 973 /* Check policy type. */ 974 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */ 975 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 976 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 977 return (EINVAL); 978 979 /* Check privileged socket. */ 980 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 981 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0); 982 if (error) 983 return (EACCES); 984 } 985 986 /* Allocating new SP entry. */ 987 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 988 return (error); 989 990 newsp->state = IPSEC_SPSTATE_ALIVE; 991 992 /* Clear old SP and set new SP. */ 993 KEY_FREESP(pcb_sp); 994 *pcb_sp = newsp; 995 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 996 printf("%s: new policy\n", __func__); 997 kdebug_secpolicy(newsp)); 998 999 return (0); 1000 } 1001 1002 int 1003 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request, 1004 size_t len, struct ucred *cred) 1005 { 1006 struct sadb_x_policy *xpl; 1007 struct secpolicy **pcb_sp; 1008 1009 /* Sanity check. */ 1010 if (inp == NULL || request == NULL) 1011 return (EINVAL); 1012 if (len < sizeof(*xpl)) 1013 return (EINVAL); 1014 xpl = (struct sadb_x_policy *)request; 1015 1016 /* Select direction. */ 1017 switch (xpl->sadb_x_policy_dir) { 1018 case IPSEC_DIR_INBOUND: 1019 pcb_sp = &inp->inp_sp->sp_in; 1020 break; 1021 case IPSEC_DIR_OUTBOUND: 1022 pcb_sp = &inp->inp_sp->sp_out; 1023 break; 1024 default: 1025 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1026 xpl->sadb_x_policy_dir)); 1027 return (EINVAL); 1028 } 1029 1030 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred)); 1031 } 1032 1033 int 1034 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len, 1035 struct mbuf **mp) 1036 { 1037 struct sadb_x_policy *xpl; 1038 struct secpolicy *pcb_sp; 1039 1040 /* Sanity check. */ 1041 if (inp == NULL || request == NULL || mp == NULL) 1042 return (EINVAL); 1043 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 1044 if (len < sizeof(*xpl)) 1045 return (EINVAL); 1046 xpl = (struct sadb_x_policy *)request; 1047 1048 /* Select direction. */ 1049 switch (xpl->sadb_x_policy_dir) { 1050 case IPSEC_DIR_INBOUND: 1051 pcb_sp = inp->inp_sp->sp_in; 1052 break; 1053 case IPSEC_DIR_OUTBOUND: 1054 pcb_sp = inp->inp_sp->sp_out; 1055 break; 1056 default: 1057 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1058 xpl->sadb_x_policy_dir)); 1059 return (EINVAL); 1060 } 1061 1062 /* Sanity check. Should be an IPSEC_ASSERT. */ 1063 if (pcb_sp == NULL) 1064 return (EINVAL); 1065 1066 *mp = key_sp2msg(pcb_sp); 1067 if (!*mp) { 1068 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 1069 return (ENOBUFS); 1070 } 1071 1072 (*mp)->m_type = MT_DATA; 1073 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1074 printf("%s:\n", __func__); kdebug_mbuf(*mp)); 1075 1076 return (0); 1077 } 1078 1079 /* Delete policy in PCB. */ 1080 int 1081 ipsec_delete_pcbpolicy(struct inpcb *inp) 1082 { 1083 IPSEC_ASSERT(inp != NULL, ("null inp")); 1084 1085 if (inp->inp_sp == NULL) 1086 return (0); 1087 1088 if (inp->inp_sp->sp_in != NULL) 1089 KEY_FREESP(&inp->inp_sp->sp_in); 1090 1091 if (inp->inp_sp->sp_out != NULL) 1092 KEY_FREESP(&inp->inp_sp->sp_out); 1093 1094 ipsec_delpcbpolicy(inp->inp_sp); 1095 inp->inp_sp = NULL; 1096 1097 return (0); 1098 } 1099 1100 /* 1101 * Return current level. 1102 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1103 */ 1104 u_int 1105 ipsec_get_reqlevel(struct ipsecrequest *isr) 1106 { 1107 u_int level = 0; 1108 u_int esp_trans_deflev, esp_net_deflev; 1109 u_int ah_trans_deflev, ah_net_deflev; 1110 1111 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument")); 1112 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1113 ("af family mismatch, src %u, dst %u", 1114 isr->sp->spidx.src.sa.sa_family, 1115 isr->sp->spidx.dst.sa.sa_family)); 1116 1117 /* XXX Note that we have ipseclog() expanded here - code sync issue. */ 1118 #define IPSEC_CHECK_DEFAULT(lev) \ 1119 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1120 && (lev) != IPSEC_LEVEL_UNIQUE) \ 1121 ? (V_ipsec_debug \ 1122 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\ 1123 (lev), IPSEC_LEVEL_REQUIRE) \ 1124 : 0), \ 1125 (lev) = IPSEC_LEVEL_REQUIRE, \ 1126 (lev) \ 1127 : (lev)) 1128 1129 /* Set default level. */ 1130 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1131 #ifdef INET 1132 case AF_INET: 1133 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev); 1134 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev); 1135 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev); 1136 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev); 1137 break; 1138 #endif 1139 #ifdef INET6 1140 case AF_INET6: 1141 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev); 1142 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev); 1143 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev); 1144 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev); 1145 break; 1146 #endif /* INET6 */ 1147 default: 1148 panic("%s: unknown af %u", 1149 __func__, isr->sp->spidx.src.sa.sa_family); 1150 } 1151 1152 #undef IPSEC_CHECK_DEFAULT 1153 1154 /* Set level. */ 1155 switch (isr->level) { 1156 case IPSEC_LEVEL_DEFAULT: 1157 switch (isr->saidx.proto) { 1158 case IPPROTO_ESP: 1159 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1160 level = esp_net_deflev; 1161 else 1162 level = esp_trans_deflev; 1163 break; 1164 case IPPROTO_AH: 1165 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1166 level = ah_net_deflev; 1167 else 1168 level = ah_trans_deflev; 1169 break; 1170 case IPPROTO_IPCOMP: 1171 /* 1172 * We don't really care, as IPcomp document says that 1173 * we shouldn't compress small packets. 1174 */ 1175 level = IPSEC_LEVEL_USE; 1176 break; 1177 default: 1178 panic("%s: Illegal protocol defined %u\n", __func__, 1179 isr->saidx.proto); 1180 } 1181 break; 1182 1183 case IPSEC_LEVEL_USE: 1184 case IPSEC_LEVEL_REQUIRE: 1185 level = isr->level; 1186 break; 1187 case IPSEC_LEVEL_UNIQUE: 1188 level = IPSEC_LEVEL_REQUIRE; 1189 break; 1190 1191 default: 1192 panic("%s: Illegal IPsec level %u\n", __func__, isr->level); 1193 } 1194 1195 return (level); 1196 } 1197 1198 /* 1199 * Check security policy requirements against the actual 1200 * packet contents. Return one if the packet should be 1201 * reject as "invalid"; otherwiser return zero to have the 1202 * packet treated as "valid". 1203 * 1204 * OUT: 1205 * 0: valid 1206 * 1: invalid 1207 */ 1208 int 1209 ipsec_in_reject(struct secpolicy *sp, struct mbuf *m) 1210 { 1211 struct ipsecrequest *isr; 1212 int need_auth; 1213 1214 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1215 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1216 1217 /* Check policy. */ 1218 switch (sp->policy) { 1219 case IPSEC_POLICY_DISCARD: 1220 return (1); 1221 case IPSEC_POLICY_BYPASS: 1222 case IPSEC_POLICY_NONE: 1223 return (0); 1224 } 1225 1226 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1227 ("invalid policy %u", sp->policy)); 1228 1229 /* XXX Should compare policy against IPsec header history. */ 1230 1231 need_auth = 0; 1232 for (isr = sp->req; isr != NULL; isr = isr->next) { 1233 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1234 continue; 1235 switch (isr->saidx.proto) { 1236 case IPPROTO_ESP: 1237 if ((m->m_flags & M_DECRYPTED) == 0) { 1238 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1239 printf("%s: ESP m_flags:%x\n", __func__, 1240 m->m_flags)); 1241 return (1); 1242 } 1243 1244 if (!need_auth && 1245 isr->sav != NULL && 1246 isr->sav->tdb_authalgxform != NULL && 1247 (m->m_flags & M_AUTHIPDGM) == 0) { 1248 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1249 printf("%s: ESP/AH m_flags:%x\n", __func__, 1250 m->m_flags)); 1251 return (1); 1252 } 1253 break; 1254 case IPPROTO_AH: 1255 need_auth = 1; 1256 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1257 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1258 printf("%s: AH m_flags:%x\n", __func__, 1259 m->m_flags)); 1260 return (1); 1261 } 1262 break; 1263 case IPPROTO_IPCOMP: 1264 /* 1265 * We don't really care, as IPcomp document 1266 * says that we shouldn't compress small 1267 * packets. IPComp policy should always be 1268 * treated as being in "use" level. 1269 */ 1270 break; 1271 } 1272 } 1273 return (0); /* Valid. */ 1274 } 1275 1276 static int 1277 ipsec46_in_reject(struct mbuf *m, struct inpcb *inp) 1278 { 1279 struct secpolicy *sp; 1280 int error; 1281 int result; 1282 1283 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1284 1285 /* 1286 * Get SP for this packet. 1287 * When we are called from ip_forward(), we call 1288 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1289 */ 1290 if (inp == NULL) 1291 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1292 else 1293 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error); 1294 1295 if (sp != NULL) { 1296 result = ipsec_in_reject(sp, m); 1297 KEY_FREESP(&sp); 1298 } else { 1299 result = 0; /* XXX Should be panic? 1300 * -> No, there may be error. */ 1301 } 1302 return (result); 1303 } 1304 1305 /* 1306 * Check AH/ESP integrity. 1307 * This function is called from tcp_input(), udp_input(), 1308 * and {ah,esp}4_input for tunnel mode. 1309 */ 1310 int 1311 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1312 { 1313 int result; 1314 1315 result = ipsec46_in_reject(m, inp); 1316 if (result) 1317 IPSECSTAT_INC(ips_in_polvio); 1318 1319 return (result); 1320 } 1321 1322 #ifdef INET6 1323 /* 1324 * Check AH/ESP integrity. 1325 * This function is called from tcp6_input(), udp6_input(), 1326 * and {ah,esp}6_input for tunnel mode. 1327 */ 1328 int 1329 ipsec6_in_reject(struct mbuf *m, struct inpcb *inp) 1330 { 1331 int result; 1332 1333 result = ipsec46_in_reject(m, inp); 1334 if (result) 1335 IPSEC6STAT_INC(ips_in_polvio); 1336 1337 return (result); 1338 } 1339 #endif 1340 1341 /* 1342 * Compute the byte size to be occupied by IPsec header. 1343 * In case it is tunnelled, it includes the size of outer IP header. 1344 * NOTE: SP passed is freed in this function. 1345 */ 1346 static size_t 1347 ipsec_hdrsiz_internal(struct secpolicy *sp) 1348 { 1349 struct ipsecrequest *isr; 1350 size_t size; 1351 1352 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1353 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1354 1355 switch (sp->policy) { 1356 case IPSEC_POLICY_DISCARD: 1357 case IPSEC_POLICY_BYPASS: 1358 case IPSEC_POLICY_NONE: 1359 return (0); 1360 } 1361 1362 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1363 ("invalid policy %u", sp->policy)); 1364 1365 size = 0; 1366 for (isr = sp->req; isr != NULL; isr = isr->next) { 1367 size_t clen = 0; 1368 1369 switch (isr->saidx.proto) { 1370 case IPPROTO_ESP: 1371 clen = esp_hdrsiz(isr->sav); 1372 break; 1373 case IPPROTO_AH: 1374 clen = ah_hdrsiz(isr->sav); 1375 break; 1376 case IPPROTO_IPCOMP: 1377 clen = sizeof(struct ipcomp); 1378 break; 1379 } 1380 1381 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1382 switch (isr->saidx.dst.sa.sa_family) { 1383 case AF_INET: 1384 clen += sizeof(struct ip); 1385 break; 1386 #ifdef INET6 1387 case AF_INET6: 1388 clen += sizeof(struct ip6_hdr); 1389 break; 1390 #endif 1391 default: 1392 ipseclog((LOG_ERR, "%s: unknown AF %d in " 1393 "IPsec tunnel SA\n", __func__, 1394 ((struct sockaddr *)&isr->saidx.dst)->sa_family)); 1395 break; 1396 } 1397 } 1398 size += clen; 1399 } 1400 1401 return (size); 1402 } 1403 1404 /* 1405 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(), 1406 * disabled ip6_ipsec_mtu() and ip6_forward(). 1407 */ 1408 size_t 1409 ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1410 { 1411 struct secpolicy *sp; 1412 int error; 1413 size_t size; 1414 1415 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1416 1417 /* Get SP for this packet. 1418 * When we are called from ip_forward(), we call 1419 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1420 */ 1421 if (inp == NULL) 1422 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1423 else 1424 sp = ipsec_getpolicybysock(m, dir, inp, &error); 1425 1426 if (sp != NULL) { 1427 size = ipsec_hdrsiz_internal(sp); 1428 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1429 printf("%s: size:%lu.\n", __func__, 1430 (unsigned long)size)); 1431 1432 KEY_FREESP(&sp); 1433 } else { 1434 size = 0; /* XXX Should be panic? 1435 * -> No, we are called w/o knowing if 1436 * IPsec processing is needed. */ 1437 } 1438 return (size); 1439 } 1440 1441 /* 1442 * Check the variable replay window. 1443 * ipsec_chkreplay() performs replay check before ICV verification. 1444 * ipsec_updatereplay() updates replay bitmap. This must be called after 1445 * ICV verification (it also performs replay check, which is usually done 1446 * beforehand). 1447 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1448 * 1449 * Based on RFC 2401. 1450 */ 1451 int 1452 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav) 1453 { 1454 const struct secreplay *replay; 1455 u_int32_t diff; 1456 int fr; 1457 u_int32_t wsizeb; /* Constant: bits of window size. */ 1458 int frlast; /* Constant: last frame. */ 1459 1460 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1461 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1462 1463 replay = sav->replay; 1464 1465 if (replay->wsize == 0) 1466 return (1); /* No need to check replay. */ 1467 1468 /* Constant. */ 1469 frlast = replay->wsize - 1; 1470 wsizeb = replay->wsize << 3; 1471 1472 /* Sequence number of 0 is invalid. */ 1473 if (seq == 0) 1474 return (0); 1475 1476 /* First time is always okay. */ 1477 if (replay->count == 0) 1478 return (1); 1479 1480 if (seq > replay->lastseq) { 1481 /* Larger sequences are okay. */ 1482 return (1); 1483 } else { 1484 /* seq is equal or less than lastseq. */ 1485 diff = replay->lastseq - seq; 1486 1487 /* Over range to check, i.e. too old or wrapped. */ 1488 if (diff >= wsizeb) 1489 return (0); 1490 1491 fr = frlast - diff / 8; 1492 1493 /* This packet already seen? */ 1494 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1495 return (0); 1496 1497 /* Out of order but good. */ 1498 return (1); 1499 } 1500 } 1501 1502 /* 1503 * Check replay counter whether to update or not. 1504 * OUT: 0: OK 1505 * 1: NG 1506 */ 1507 int 1508 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav) 1509 { 1510 struct secreplay *replay; 1511 u_int32_t diff; 1512 int fr; 1513 u_int32_t wsizeb; /* Constant: bits of window size. */ 1514 int frlast; /* Constant: last frame. */ 1515 1516 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1517 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1518 1519 replay = sav->replay; 1520 1521 if (replay->wsize == 0) 1522 goto ok; /* No need to check replay. */ 1523 1524 /* Constant. */ 1525 frlast = replay->wsize - 1; 1526 wsizeb = replay->wsize << 3; 1527 1528 /* Sequence number of 0 is invalid. */ 1529 if (seq == 0) 1530 return (1); 1531 1532 /* First time. */ 1533 if (replay->count == 0) { 1534 replay->lastseq = seq; 1535 bzero(replay->bitmap, replay->wsize); 1536 (replay->bitmap)[frlast] = 1; 1537 goto ok; 1538 } 1539 1540 if (seq > replay->lastseq) { 1541 /* seq is larger than lastseq. */ 1542 diff = seq - replay->lastseq; 1543 1544 /* New larger sequence number. */ 1545 if (diff < wsizeb) { 1546 /* In window. */ 1547 /* Set bit for this packet. */ 1548 vshiftl(replay->bitmap, diff, replay->wsize); 1549 (replay->bitmap)[frlast] |= 1; 1550 } else { 1551 /* This packet has a "way larger". */ 1552 bzero(replay->bitmap, replay->wsize); 1553 (replay->bitmap)[frlast] = 1; 1554 } 1555 replay->lastseq = seq; 1556 1557 /* Larger is good. */ 1558 } else { 1559 /* seq is equal or less than lastseq. */ 1560 diff = replay->lastseq - seq; 1561 1562 /* Over range to check, i.e. too old or wrapped. */ 1563 if (diff >= wsizeb) 1564 return (1); 1565 1566 fr = frlast - diff / 8; 1567 1568 /* This packet already seen? */ 1569 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1570 return (1); 1571 1572 /* Mark as seen. */ 1573 (replay->bitmap)[fr] |= (1 << (diff % 8)); 1574 1575 /* Out of order but good. */ 1576 } 1577 1578 ok: 1579 if (replay->count == ~0) { 1580 1581 /* Set overflow flag. */ 1582 replay->overflow++; 1583 1584 /* Don't increment, no more packets accepted. */ 1585 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 1586 return (1); 1587 1588 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1589 __func__, replay->overflow, ipsec_logsastr(sav))); 1590 } 1591 1592 replay->count++; 1593 1594 return (0); 1595 } 1596 1597 /* 1598 * Shift variable length buffer to left. 1599 * IN: bitmap: pointer to the buffer 1600 * nbit: the number of to shift. 1601 * wsize: buffer size (bytes). 1602 */ 1603 static void 1604 vshiftl(unsigned char *bitmap, int nbit, int wsize) 1605 { 1606 int s, j, i; 1607 unsigned char over; 1608 1609 for (j = 0; j < nbit; j += 8) { 1610 s = (nbit - j < 8) ? (nbit - j): 8; 1611 bitmap[0] <<= s; 1612 for (i = 1; i < wsize; i++) { 1613 over = (bitmap[i] >> (8 - s)); 1614 bitmap[i] <<= s; 1615 bitmap[i-1] |= over; 1616 } 1617 } 1618 } 1619 1620 #ifdef INET 1621 /* Return a printable string for the IPv4 address. */ 1622 static char * 1623 inet_ntoa4(struct in_addr ina) 1624 { 1625 static char buf[4][4 * sizeof "123" + 4]; 1626 unsigned char *ucp = (unsigned char *) &ina; 1627 static int i = 3; 1628 1629 /* XXX-BZ Returns static buffer. */ 1630 i = (i + 1) % 4; 1631 sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff, 1632 ucp[2] & 0xff, ucp[3] & 0xff); 1633 return (buf[i]); 1634 } 1635 #endif 1636 1637 /* Return a printable string for the address. */ 1638 char * 1639 ipsec_address(union sockaddr_union* sa) 1640 { 1641 #ifdef INET6 1642 char ip6buf[INET6_ADDRSTRLEN]; 1643 #endif 1644 1645 switch (sa->sa.sa_family) { 1646 #ifdef INET 1647 case AF_INET: 1648 return (inet_ntoa4(sa->sin.sin_addr)); 1649 #endif /* INET */ 1650 #ifdef INET6 1651 case AF_INET6: 1652 return (ip6_sprintf(ip6buf, &sa->sin6.sin6_addr)); 1653 #endif /* INET6 */ 1654 default: 1655 return ("(unknown address family)"); 1656 } 1657 } 1658 1659 const char * 1660 ipsec_logsastr(struct secasvar *sav) 1661 { 1662 static char buf[256]; 1663 char *p; 1664 struct secasindex *saidx = &sav->sah->saidx; 1665 1666 IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 1667 ("address family mismatch")); 1668 1669 p = buf; 1670 snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi)); 1671 while (p && *p) 1672 p++; 1673 /* NB: only use ipsec_address on one address at a time. */ 1674 snprintf(p, sizeof (buf) - (p - buf), "src=%s ", 1675 ipsec_address(&saidx->src)); 1676 while (p && *p) 1677 p++; 1678 snprintf(p, sizeof (buf) - (p - buf), "dst=%s)", 1679 ipsec_address(&saidx->dst)); 1680 1681 return (buf); 1682 } 1683 1684 void 1685 ipsec_dumpmbuf(struct mbuf *m) 1686 { 1687 int totlen; 1688 int i; 1689 u_char *p; 1690 1691 totlen = 0; 1692 printf("---\n"); 1693 while (m) { 1694 p = mtod(m, u_char *); 1695 for (i = 0; i < m->m_len; i++) { 1696 printf("%02x ", p[i]); 1697 totlen++; 1698 if (totlen % 16 == 0) 1699 printf("\n"); 1700 } 1701 m = m->m_next; 1702 } 1703 if (totlen % 16 != 0) 1704 printf("\n"); 1705 printf("---\n"); 1706 } 1707 1708 static void 1709 ipsec_init(const void *unused __unused) 1710 { 1711 1712 SECPOLICY_LOCK_INIT(&V_ip4_def_policy); 1713 V_ip4_def_policy.refcnt = 1; /* NB: disallow free. */ 1714 } 1715 VNET_SYSINIT(ipsec_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, ipsec_init, 1716 NULL); 1717 1718 1719 /* XXX This stuff doesn't belong here... */ 1720 1721 static struct xformsw* xforms = NULL; 1722 1723 /* 1724 * Register a transform; typically at system startup. 1725 */ 1726 void 1727 xform_register(struct xformsw* xsp) 1728 { 1729 1730 xsp->xf_next = xforms; 1731 xforms = xsp; 1732 } 1733 1734 /* 1735 * Initialize transform support in an sav. 1736 */ 1737 int 1738 xform_init(struct secasvar *sav, int xftype) 1739 { 1740 struct xformsw *xsp; 1741 1742 if (sav->tdb_xform != NULL) /* Previously initialized. */ 1743 return (0); 1744 for (xsp = xforms; xsp; xsp = xsp->xf_next) 1745 if (xsp->xf_type == xftype) 1746 return ((*xsp->xf_init)(sav, xsp)); 1747 return (EINVAL); 1748 } 1749