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