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/if_var.h> 59 #include <net/route.h> 60 #include <net/vnet.h> 61 62 #include <netinet/in.h> 63 #include <netinet/in_systm.h> 64 #include <netinet/ip.h> 65 #include <netinet/ip_var.h> 66 #include <netinet/in_var.h> 67 #include <netinet/udp.h> 68 #include <netinet/udp_var.h> 69 #include <netinet/tcp.h> 70 #include <netinet/udp.h> 71 72 #include <netinet/ip6.h> 73 #ifdef INET6 74 #include <netinet6/ip6_var.h> 75 #endif 76 #include <netinet/in_pcb.h> 77 #ifdef INET6 78 #include <netinet/icmp6.h> 79 #endif 80 81 #include <sys/types.h> 82 #include <netipsec/ipsec.h> 83 #ifdef INET6 84 #include <netipsec/ipsec6.h> 85 #endif 86 #include <netipsec/ah_var.h> 87 #include <netipsec/esp_var.h> 88 #include <netipsec/ipcomp.h> /*XXX*/ 89 #include <netipsec/ipcomp_var.h> 90 91 #include <netipsec/key.h> 92 #include <netipsec/keydb.h> 93 #include <netipsec/key_debug.h> 94 95 #include <netipsec/xform.h> 96 97 #include <machine/in_cksum.h> 98 99 #include <opencrypto/cryptodev.h> 100 101 #ifdef IPSEC_DEBUG 102 VNET_DEFINE(int, ipsec_debug) = 1; 103 #else 104 VNET_DEFINE(int, ipsec_debug) = 0; 105 #endif 106 107 /* NB: name changed so netstat doesn't use it. */ 108 VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec4stat); 109 VNET_PCPUSTAT_SYSINIT(ipsec4stat); 110 111 #ifdef VIMAGE 112 VNET_PCPUSTAT_SYSUNINIT(ipsec4stat); 113 #endif /* VIMAGE */ 114 115 VNET_DEFINE(int, ip4_ah_offsetmask) = 0; /* maybe IP_DF? */ 116 /* DF bit on encap. 0: clear 1: set 2: copy */ 117 VNET_DEFINE(int, ip4_ipsec_dfbit) = 0; 118 VNET_DEFINE(int, ip4_esp_trans_deflev) = IPSEC_LEVEL_USE; 119 VNET_DEFINE(int, ip4_esp_net_deflev) = IPSEC_LEVEL_USE; 120 VNET_DEFINE(int, ip4_ah_trans_deflev) = IPSEC_LEVEL_USE; 121 VNET_DEFINE(int, ip4_ah_net_deflev) = IPSEC_LEVEL_USE; 122 VNET_DEFINE(struct secpolicy, ip4_def_policy); 123 /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 124 VNET_DEFINE(int, ip4_ipsec_ecn) = 0; 125 VNET_DEFINE(int, ip4_esp_randpad) = -1; 126 127 /* 128 * Crypto support requirements: 129 * 130 * 1 require hardware support 131 * -1 require software support 132 * 0 take anything 133 */ 134 VNET_DEFINE(int, crypto_support) = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE; 135 136 FEATURE(ipsec, "Internet Protocol Security (IPsec)"); 137 #ifdef IPSEC_NAT_T 138 FEATURE(ipsec_natt, "UDP Encapsulation of IPsec ESP Packets ('NAT-T')"); 139 #endif 140 141 SYSCTL_DECL(_net_inet_ipsec); 142 143 /* net.inet.ipsec */ 144 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy, 145 CTLFLAG_RW, &VNET_NAME(ip4_def_policy).policy, 0, 146 "IPsec default policy."); 147 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev, 148 CTLFLAG_RW, &VNET_NAME(ip4_esp_trans_deflev), 0, 149 "Default ESP transport mode level"); 150 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev, 151 CTLFLAG_RW, &VNET_NAME(ip4_esp_net_deflev), 0, 152 "Default ESP tunnel mode level."); 153 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev, 154 CTLFLAG_RW, &VNET_NAME(ip4_ah_trans_deflev), 0, 155 "AH transfer mode default level."); 156 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev, 157 CTLFLAG_RW, &VNET_NAME(ip4_ah_net_deflev), 0, 158 "AH tunnel mode default level."); 159 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos, 160 CTLFLAG_RW, &VNET_NAME(ah_cleartos), 0, 161 "If set clear type-of-service field when doing AH computation."); 162 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, ah_offsetmask, 163 CTLFLAG_RW, &VNET_NAME(ip4_ah_offsetmask), 0, 164 "If not set clear offset field mask when doing AH computation."); 165 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit, 166 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_dfbit), 0, 167 "Do not fragment bit on encap."); 168 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn, 169 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_ecn), 0, 170 "Explicit Congestion Notification handling."); 171 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEBUG, debug, 172 CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0, 173 "Enable IPsec debugging output when set."); 174 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, crypto_support, 175 CTLFLAG_RW, &VNET_NAME(crypto_support), 0, 176 "Crypto driver selection."); 177 SYSCTL_VNET_PCPUSTAT(_net_inet_ipsec, OID_AUTO, ipsecstats, struct ipsecstat, 178 ipsec4stat, "IPsec IPv4 statistics."); 179 180 #ifdef REGRESSION 181 /* 182 * When set to 1, IPsec will send packets with the same sequence number. 183 * This allows to verify if the other side has proper replay attacks detection. 184 */ 185 VNET_DEFINE(int, ipsec_replay) = 0; 186 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_replay, 187 CTLFLAG_RW, &VNET_NAME(ipsec_replay), 0, 188 "Emulate replay attack"); 189 /* 190 * When set 1, IPsec will send packets with corrupted HMAC. 191 * This allows to verify if the other side properly detects modified packets. 192 */ 193 VNET_DEFINE(int, ipsec_integrity) = 0; 194 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_integrity, 195 CTLFLAG_RW, &VNET_NAME(ipsec_integrity), 0, 196 "Emulate man-in-the-middle attack"); 197 #endif 198 199 #ifdef INET6 200 VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec6stat); 201 VNET_PCPUSTAT_SYSINIT(ipsec6stat); 202 203 #ifdef VIMAGE 204 VNET_PCPUSTAT_SYSUNINIT(ipsec6stat); 205 #endif /* VIMAGE */ 206 207 VNET_DEFINE(int, ip6_esp_trans_deflev) = IPSEC_LEVEL_USE; 208 VNET_DEFINE(int, ip6_esp_net_deflev) = IPSEC_LEVEL_USE; 209 VNET_DEFINE(int, ip6_ah_trans_deflev) = IPSEC_LEVEL_USE; 210 VNET_DEFINE(int, ip6_ah_net_deflev) = IPSEC_LEVEL_USE; 211 VNET_DEFINE(int, ip6_ipsec_ecn) = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 212 213 SYSCTL_DECL(_net_inet6_ipsec6); 214 215 /* net.inet6.ipsec6 */ 216 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy, CTLFLAG_RW, 217 &VNET_NAME(ip4_def_policy).policy, 0, 218 "IPsec default policy."); 219 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV, 220 esp_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_trans_deflev), 0, 221 "Default ESP transport mode level."); 222 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV, 223 esp_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_net_deflev), 0, 224 "Default ESP tunnel mode level."); 225 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV, 226 ah_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_trans_deflev), 0, 227 "AH transfer mode default level."); 228 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV, 229 ah_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_net_deflev), 0, 230 "AH tunnel mode default level."); 231 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_ECN, 232 ecn, CTLFLAG_RW, &VNET_NAME(ip6_ipsec_ecn), 0, 233 "Explicit Congestion Notification handling."); 234 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEBUG, debug, CTLFLAG_RW, 235 &VNET_NAME(ipsec_debug), 0, 236 "Enable IPsec debugging output when set."); 237 SYSCTL_VNET_PCPUSTAT(_net_inet6_ipsec6, IPSECCTL_STATS, ipsecstats, 238 struct ipsecstat, ipsec6stat, "IPsec IPv6 statistics."); 239 #endif /* INET6 */ 240 241 static int ipsec_setspidx_inpcb __P((struct mbuf *, struct inpcb *)); 242 static int ipsec_setspidx __P((struct mbuf *, struct secpolicyindex *, int)); 243 static void ipsec4_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 244 static int ipsec4_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 245 #ifdef INET6 246 static void ipsec6_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 247 static int ipsec6_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 248 #endif 249 static void ipsec_delpcbpolicy __P((struct inpcbpolicy *)); 250 static struct secpolicy *ipsec_deepcopy_policy __P((struct secpolicy *src)); 251 static void vshiftl __P((unsigned char *, int, int)); 252 253 MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy"); 254 255 /* 256 * Return a held reference to the default SP. 257 */ 258 static struct secpolicy * 259 key_allocsp_default(const char* where, int tag) 260 { 261 struct secpolicy *sp; 262 263 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 264 printf("DP key_allocsp_default from %s:%u\n", where, tag)); 265 266 sp = &V_ip4_def_policy; 267 if (sp->policy != IPSEC_POLICY_DISCARD && 268 sp->policy != IPSEC_POLICY_NONE) { 269 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n", 270 sp->policy, IPSEC_POLICY_NONE)); 271 sp->policy = IPSEC_POLICY_NONE; 272 } 273 key_addref(sp); 274 275 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 276 printf("DP key_allocsp_default returns SP:%p (%u)\n", 277 sp, sp->refcnt)); 278 return (sp); 279 } 280 #define KEY_ALLOCSP_DEFAULT() \ 281 key_allocsp_default(__FILE__, __LINE__) 282 283 /* 284 * For OUTBOUND packet having a socket. Searching SPD for packet, 285 * and return a pointer to SP. 286 * OUT: NULL: no apropreate SP found, the following value is set to error. 287 * 0 : bypass 288 * EACCES : discard packet. 289 * ENOENT : ipsec_acquire() in progress, maybe. 290 * others : error occured. 291 * others: a pointer to SP 292 * 293 * NOTE: IPv6 mapped adddress concern is implemented here. 294 */ 295 struct secpolicy * 296 ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir) 297 { 298 struct secpolicy *sp; 299 300 IPSEC_ASSERT(tdbi != NULL, ("null tdbi")); 301 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 302 ("invalid direction %u", dir)); 303 304 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir); 305 if (sp == NULL) /*XXX????*/ 306 sp = KEY_ALLOCSP_DEFAULT(); 307 IPSEC_ASSERT(sp != NULL, ("null SP")); 308 return (sp); 309 } 310 311 /* 312 * For OUTBOUND packet having a socket. Searching SPD for packet, 313 * and return a pointer to SP. 314 * OUT: NULL: no apropreate SP found, the following value is set to error. 315 * 0 : bypass 316 * EACCES : discard packet. 317 * ENOENT : ipsec_acquire() in progress, maybe. 318 * others : error occured. 319 * others: a pointer to SP 320 * 321 * NOTE: IPv6 mapped adddress concern is implemented here. 322 */ 323 static struct secpolicy * 324 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb *inp, int *error) 325 { 326 struct inpcbpolicy *pcbsp; 327 struct secpolicy *currsp = NULL; /* Policy on socket. */ 328 struct secpolicy *sp; 329 330 IPSEC_ASSERT(m != NULL, ("null mbuf")); 331 IPSEC_ASSERT(inp != NULL, ("null inpcb")); 332 IPSEC_ASSERT(error != NULL, ("null error")); 333 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 334 ("invalid direction %u", dir)); 335 336 /* Set spidx in pcb. */ 337 *error = ipsec_setspidx_inpcb(m, inp); 338 if (*error) 339 return (NULL); 340 341 pcbsp = inp->inp_sp; 342 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp")); 343 switch (dir) { 344 case IPSEC_DIR_INBOUND: 345 currsp = pcbsp->sp_in; 346 break; 347 case IPSEC_DIR_OUTBOUND: 348 currsp = pcbsp->sp_out; 349 break; 350 } 351 IPSEC_ASSERT(currsp != NULL, ("null currsp")); 352 353 if (pcbsp->priv) { /* When privilieged socket. */ 354 switch (currsp->policy) { 355 case IPSEC_POLICY_BYPASS: 356 case IPSEC_POLICY_IPSEC: 357 key_addref(currsp); 358 sp = currsp; 359 break; 360 361 case IPSEC_POLICY_ENTRUST: 362 /* Look for a policy in SPD. */ 363 sp = KEY_ALLOCSP(&currsp->spidx, dir); 364 if (sp == NULL) /* No SP found. */ 365 sp = KEY_ALLOCSP_DEFAULT(); 366 break; 367 368 default: 369 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n", 370 __func__, currsp->policy)); 371 *error = EINVAL; 372 return (NULL); 373 } 374 } else { /* Unpriv, SPD has policy. */ 375 sp = KEY_ALLOCSP(&currsp->spidx, dir); 376 if (sp == NULL) { /* No SP found. */ 377 switch (currsp->policy) { 378 case IPSEC_POLICY_BYPASS: 379 ipseclog((LOG_ERR, "%s: Illegal policy for " 380 "non-priviliged defined %d\n", 381 __func__, currsp->policy)); 382 *error = EINVAL; 383 return (NULL); 384 385 case IPSEC_POLICY_ENTRUST: 386 sp = KEY_ALLOCSP_DEFAULT(); 387 break; 388 389 case IPSEC_POLICY_IPSEC: 390 key_addref(currsp); 391 sp = currsp; 392 break; 393 394 default: 395 ipseclog((LOG_ERR, "%s: Invalid policy for " 396 "PCB %d\n", __func__, currsp->policy)); 397 *error = EINVAL; 398 return (NULL); 399 } 400 } 401 } 402 IPSEC_ASSERT(sp != NULL, 403 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy)); 404 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 405 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n", 406 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt)); 407 return (sp); 408 } 409 410 /* 411 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 412 * and return a pointer to SP. 413 * OUT: positive: a pointer to the entry for security policy leaf matched. 414 * NULL: no apropreate SP found, the following value is set to error. 415 * 0 : bypass 416 * EACCES : discard packet. 417 * ENOENT : ipsec_acquire() in progress, maybe. 418 * others : error occured. 419 */ 420 struct secpolicy * 421 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 422 { 423 struct secpolicyindex spidx; 424 struct secpolicy *sp; 425 426 IPSEC_ASSERT(m != NULL, ("null mbuf")); 427 IPSEC_ASSERT(error != NULL, ("null error")); 428 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 429 ("invalid direction %u", dir)); 430 431 sp = NULL; 432 if (key_havesp(dir)) { 433 /* Make an index to look for a policy. */ 434 *error = ipsec_setspidx(m, &spidx, 435 (flag & IP_FORWARDING) ? 0 : 1); 436 if (*error != 0) { 437 DPRINTF(("%s: setpidx failed, dir %u flag %u\n", 438 __func__, dir, flag)); 439 return (NULL); 440 } 441 spidx.dir = dir; 442 443 sp = KEY_ALLOCSP(&spidx, dir); 444 } 445 if (sp == NULL) /* No SP found, use system default. */ 446 sp = KEY_ALLOCSP_DEFAULT(); 447 IPSEC_ASSERT(sp != NULL, ("null SP")); 448 return (sp); 449 } 450 451 struct secpolicy * 452 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 453 struct inpcb *inp) 454 { 455 struct secpolicy *sp; 456 457 *error = 0; 458 if (inp == NULL) 459 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 460 else 461 sp = ipsec_getpolicybysock(m, dir, inp, error); 462 if (sp == NULL) { 463 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error")); 464 IPSECSTAT_INC(ips_out_inval); 465 return (NULL); 466 } 467 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error)); 468 switch (sp->policy) { 469 case IPSEC_POLICY_ENTRUST: 470 default: 471 printf("%s: invalid policy %u\n", __func__, sp->policy); 472 /* FALLTHROUGH */ 473 case IPSEC_POLICY_DISCARD: 474 IPSECSTAT_INC(ips_out_polvio); 475 *error = -EINVAL; /* Packet is discarded by caller. */ 476 break; 477 case IPSEC_POLICY_BYPASS: 478 case IPSEC_POLICY_NONE: 479 KEY_FREESP(&sp); 480 sp = NULL; /* NB: force NULL result. */ 481 break; 482 case IPSEC_POLICY_IPSEC: 483 if (sp->req == NULL) /* Acquire a SA. */ 484 *error = key_spdacquire(sp); 485 break; 486 } 487 if (*error != 0) { 488 KEY_FREESP(&sp); 489 sp = NULL; 490 } 491 return (sp); 492 } 493 494 static int 495 ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp) 496 { 497 int error; 498 499 IPSEC_ASSERT(inp != NULL, ("null inp")); 500 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 501 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL, 502 ("null sp_in || sp_out")); 503 504 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1); 505 if (error == 0) { 506 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 507 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx; 508 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 509 } else { 510 bzero(&inp->inp_sp->sp_in->spidx, 511 sizeof (inp->inp_sp->sp_in->spidx)); 512 bzero(&inp->inp_sp->sp_out->spidx, 513 sizeof (inp->inp_sp->sp_in->spidx)); 514 } 515 return (error); 516 } 517 518 /* 519 * Configure security policy index (src/dst/proto/sport/dport) 520 * by looking at the content of mbuf. 521 * The caller is responsible for error recovery (like clearing up spidx). 522 */ 523 static int 524 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 525 { 526 struct ip *ip = NULL; 527 struct ip ipbuf; 528 u_int v; 529 struct mbuf *n; 530 int len; 531 int error; 532 533 IPSEC_ASSERT(m != NULL, ("null mbuf")); 534 535 /* 536 * Validate m->m_pkthdr.len. We see incorrect length if we 537 * mistakenly call this function with inconsistent mbuf chain 538 * (like 4.4BSD tcp/udp processing). XXX Should we panic here? 539 */ 540 len = 0; 541 for (n = m; n; n = n->m_next) 542 len += n->m_len; 543 if (m->m_pkthdr.len != len) { 544 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 545 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n", 546 __func__, len, m->m_pkthdr.len)); 547 return (EINVAL); 548 } 549 550 if (m->m_pkthdr.len < sizeof(struct ip)) { 551 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 552 printf("%s: pkthdr len(%d) too small (v4), ignored.\n", 553 __func__, m->m_pkthdr.len)); 554 return (EINVAL); 555 } 556 557 if (m->m_len >= sizeof(*ip)) 558 ip = mtod(m, struct ip *); 559 else { 560 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf); 561 ip = &ipbuf; 562 } 563 #ifdef _IP_VHL 564 v = _IP_VHL_V(ip->ip_vhl); 565 #else 566 v = ip->ip_v; 567 #endif 568 switch (v) { 569 case 4: 570 error = ipsec4_setspidx_ipaddr(m, spidx); 571 if (error) 572 return (error); 573 ipsec4_get_ulp(m, spidx, needport); 574 return (0); 575 #ifdef INET6 576 case 6: 577 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 578 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 579 printf("%s: pkthdr len(%d) too small (v6), " 580 "ignored\n", __func__, m->m_pkthdr.len)); 581 return (EINVAL); 582 } 583 error = ipsec6_setspidx_ipaddr(m, spidx); 584 if (error) 585 return (error); 586 ipsec6_get_ulp(m, spidx, needport); 587 return (0); 588 #endif 589 default: 590 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 591 printf("%s: " "unknown IP version %u, ignored.\n", 592 __func__, v)); 593 return (EINVAL); 594 } 595 } 596 597 static void 598 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 599 { 600 u_int8_t nxt; 601 int off; 602 603 /* Sanity check. */ 604 IPSEC_ASSERT(m != NULL, ("null mbuf")); 605 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short")); 606 607 if (m->m_len >= sizeof (struct ip)) { 608 struct ip *ip = mtod(m, struct ip *); 609 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 610 goto done; 611 #ifdef _IP_VHL 612 off = _IP_VHL_HL(ip->ip_vhl) << 2; 613 #else 614 off = ip->ip_hl << 2; 615 #endif 616 nxt = ip->ip_p; 617 } else { 618 struct ip ih; 619 620 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih); 621 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 622 goto done; 623 #ifdef _IP_VHL 624 off = _IP_VHL_HL(ih.ip_vhl) << 2; 625 #else 626 off = ih.ip_hl << 2; 627 #endif 628 nxt = ih.ip_p; 629 } 630 631 while (off < m->m_pkthdr.len) { 632 struct ip6_ext ip6e; 633 struct tcphdr th; 634 struct udphdr uh; 635 636 switch (nxt) { 637 case IPPROTO_TCP: 638 spidx->ul_proto = nxt; 639 if (!needport) 640 goto done_proto; 641 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 642 goto done; 643 m_copydata(m, off, sizeof (th), (caddr_t) &th); 644 spidx->src.sin.sin_port = th.th_sport; 645 spidx->dst.sin.sin_port = th.th_dport; 646 return; 647 case IPPROTO_UDP: 648 spidx->ul_proto = nxt; 649 if (!needport) 650 goto done_proto; 651 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 652 goto done; 653 m_copydata(m, off, sizeof (uh), (caddr_t) &uh); 654 spidx->src.sin.sin_port = uh.uh_sport; 655 spidx->dst.sin.sin_port = uh.uh_dport; 656 return; 657 case IPPROTO_AH: 658 if (off + sizeof(ip6e) > m->m_pkthdr.len) 659 goto done; 660 /* XXX Sigh, this works but is totally bogus. */ 661 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e); 662 off += (ip6e.ip6e_len + 2) << 2; 663 nxt = ip6e.ip6e_nxt; 664 break; 665 case IPPROTO_ICMP: 666 default: 667 /* XXX Intermediate headers??? */ 668 spidx->ul_proto = nxt; 669 goto done_proto; 670 } 671 } 672 done: 673 spidx->ul_proto = IPSEC_ULPROTO_ANY; 674 done_proto: 675 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 676 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 677 } 678 679 /* Assumes that m is sane. */ 680 static int 681 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 682 { 683 static const struct sockaddr_in template = { 684 sizeof (struct sockaddr_in), 685 AF_INET, 686 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 687 }; 688 689 spidx->src.sin = template; 690 spidx->dst.sin = template; 691 692 if (m->m_len < sizeof (struct ip)) { 693 m_copydata(m, offsetof(struct ip, ip_src), 694 sizeof (struct in_addr), 695 (caddr_t) &spidx->src.sin.sin_addr); 696 m_copydata(m, offsetof(struct ip, ip_dst), 697 sizeof (struct in_addr), 698 (caddr_t) &spidx->dst.sin.sin_addr); 699 } else { 700 struct ip *ip = mtod(m, struct ip *); 701 spidx->src.sin.sin_addr = ip->ip_src; 702 spidx->dst.sin.sin_addr = ip->ip_dst; 703 } 704 705 spidx->prefs = sizeof(struct in_addr) << 3; 706 spidx->prefd = sizeof(struct in_addr) << 3; 707 708 return (0); 709 } 710 711 #ifdef INET6 712 static void 713 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 714 { 715 int off, nxt; 716 struct tcphdr th; 717 struct udphdr uh; 718 struct icmp6_hdr ih; 719 720 /* Sanity check. */ 721 if (m == NULL) 722 panic("%s: NULL pointer was passed.\n", __func__); 723 724 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 725 printf("%s:\n", __func__); kdebug_mbuf(m)); 726 727 /* Set default. */ 728 spidx->ul_proto = IPSEC_ULPROTO_ANY; 729 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 730 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 731 732 nxt = -1; 733 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 734 if (off < 0 || m->m_pkthdr.len < off) 735 return; 736 737 switch (nxt) { 738 case IPPROTO_TCP: 739 spidx->ul_proto = nxt; 740 if (!needport) 741 break; 742 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 743 break; 744 m_copydata(m, off, sizeof(th), (caddr_t)&th); 745 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 746 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 747 break; 748 case IPPROTO_UDP: 749 spidx->ul_proto = nxt; 750 if (!needport) 751 break; 752 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 753 break; 754 m_copydata(m, off, sizeof(uh), (caddr_t)&uh); 755 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 756 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 757 break; 758 case IPPROTO_ICMPV6: 759 spidx->ul_proto = nxt; 760 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 761 break; 762 m_copydata(m, off, sizeof(ih), (caddr_t)&ih); 763 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 764 htons((uint16_t)ih.icmp6_type); 765 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 766 htons((uint16_t)ih.icmp6_code); 767 break; 768 default: 769 /* XXX Intermediate headers??? */ 770 spidx->ul_proto = nxt; 771 break; 772 } 773 } 774 775 /* Assumes that m is sane. */ 776 static int 777 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 778 { 779 struct ip6_hdr *ip6 = NULL; 780 struct ip6_hdr ip6buf; 781 struct sockaddr_in6 *sin6; 782 783 if (m->m_len >= sizeof(*ip6)) 784 ip6 = mtod(m, struct ip6_hdr *); 785 else { 786 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf); 787 ip6 = &ip6buf; 788 } 789 790 sin6 = (struct sockaddr_in6 *)&spidx->src; 791 bzero(sin6, sizeof(*sin6)); 792 sin6->sin6_family = AF_INET6; 793 sin6->sin6_len = sizeof(struct sockaddr_in6); 794 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src)); 795 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 796 sin6->sin6_addr.s6_addr16[1] = 0; 797 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 798 } 799 spidx->prefs = sizeof(struct in6_addr) << 3; 800 801 sin6 = (struct sockaddr_in6 *)&spidx->dst; 802 bzero(sin6, sizeof(*sin6)); 803 sin6->sin6_family = AF_INET6; 804 sin6->sin6_len = sizeof(struct sockaddr_in6); 805 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst)); 806 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 807 sin6->sin6_addr.s6_addr16[1] = 0; 808 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 809 } 810 spidx->prefd = sizeof(struct in6_addr) << 3; 811 812 return (0); 813 } 814 #endif 815 816 static void 817 ipsec_delpcbpolicy(struct inpcbpolicy *p) 818 { 819 820 free(p, M_IPSEC_INPCB); 821 } 822 823 /* Initialize policy in PCB. */ 824 int 825 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp) 826 { 827 struct inpcbpolicy *new; 828 829 /* Sanity check. */ 830 if (so == NULL || pcb_sp == NULL) 831 panic("%s: NULL pointer was passed.\n", __func__); 832 833 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy), 834 M_IPSEC_INPCB, M_NOWAIT|M_ZERO); 835 if (new == NULL) { 836 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 837 return (ENOBUFS); 838 } 839 840 new->priv = IPSEC_IS_PRIVILEGED_SO(so); 841 842 if ((new->sp_in = KEY_NEWSP()) == NULL) { 843 ipsec_delpcbpolicy(new); 844 return (ENOBUFS); 845 } 846 new->sp_in->state = IPSEC_SPSTATE_ALIVE; 847 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 848 849 if ((new->sp_out = KEY_NEWSP()) == NULL) { 850 KEY_FREESP(&new->sp_in); 851 ipsec_delpcbpolicy(new); 852 return (ENOBUFS); 853 } 854 new->sp_out->state = IPSEC_SPSTATE_ALIVE; 855 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 856 857 *pcb_sp = new; 858 859 return (0); 860 } 861 862 /* Copy old IPsec policy into new. */ 863 int 864 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new) 865 { 866 struct secpolicy *sp; 867 868 sp = ipsec_deepcopy_policy(old->sp_in); 869 if (sp) { 870 KEY_FREESP(&new->sp_in); 871 new->sp_in = sp; 872 } else 873 return (ENOBUFS); 874 875 sp = ipsec_deepcopy_policy(old->sp_out); 876 if (sp) { 877 KEY_FREESP(&new->sp_out); 878 new->sp_out = sp; 879 } else 880 return (ENOBUFS); 881 882 new->priv = old->priv; 883 884 return (0); 885 } 886 887 struct ipsecrequest * 888 ipsec_newisr(void) 889 { 890 struct ipsecrequest *p; 891 892 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO); 893 if (p != NULL) 894 IPSECREQUEST_LOCK_INIT(p); 895 return (p); 896 } 897 898 void 899 ipsec_delisr(struct ipsecrequest *p) 900 { 901 902 IPSECREQUEST_LOCK_DESTROY(p); 903 free(p, M_IPSEC_SR); 904 } 905 906 /* Deep-copy a policy in PCB. */ 907 static struct secpolicy * 908 ipsec_deepcopy_policy(struct secpolicy *src) 909 { 910 struct ipsecrequest *newchain = NULL; 911 struct ipsecrequest *p; 912 struct ipsecrequest **q; 913 struct ipsecrequest *r; 914 struct secpolicy *dst; 915 916 if (src == NULL) 917 return (NULL); 918 dst = KEY_NEWSP(); 919 if (dst == NULL) 920 return (NULL); 921 922 /* 923 * Deep-copy IPsec request chain. This is required since struct 924 * ipsecrequest is not reference counted. 925 */ 926 q = &newchain; 927 for (p = src->req; p; p = p->next) { 928 *q = ipsec_newisr(); 929 if (*q == NULL) 930 goto fail; 931 (*q)->saidx.proto = p->saidx.proto; 932 (*q)->saidx.mode = p->saidx.mode; 933 (*q)->level = p->level; 934 (*q)->saidx.reqid = p->saidx.reqid; 935 936 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src)); 937 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst)); 938 939 (*q)->sp = dst; 940 941 q = &((*q)->next); 942 } 943 944 dst->req = newchain; 945 dst->state = src->state; 946 dst->policy = src->policy; 947 /* Do not touch the refcnt fields. */ 948 949 return (dst); 950 951 fail: 952 for (p = newchain; p; p = r) { 953 r = p->next; 954 ipsec_delisr(p); 955 p = NULL; 956 } 957 return (NULL); 958 } 959 960 /* Set policy and IPsec request if present. */ 961 static int 962 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname, 963 caddr_t request, size_t len, struct ucred *cred) 964 { 965 struct sadb_x_policy *xpl; 966 struct secpolicy *newsp = NULL; 967 int error; 968 969 /* Sanity check. */ 970 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL) 971 return (EINVAL); 972 if (len < sizeof(*xpl)) 973 return (EINVAL); 974 xpl = (struct sadb_x_policy *)request; 975 976 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 977 printf("%s: passed policy\n", __func__); 978 kdebug_sadb_x_policy((struct sadb_ext *)xpl)); 979 980 /* Check policy type. */ 981 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */ 982 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 983 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 984 return (EINVAL); 985 986 /* Check privileged socket. */ 987 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 988 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0); 989 if (error) 990 return (EACCES); 991 } 992 993 /* Allocating new SP entry. */ 994 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 995 return (error); 996 997 newsp->state = IPSEC_SPSTATE_ALIVE; 998 999 /* Clear old SP and set new SP. */ 1000 KEY_FREESP(pcb_sp); 1001 *pcb_sp = newsp; 1002 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1003 printf("%s: new policy\n", __func__); 1004 kdebug_secpolicy(newsp)); 1005 1006 return (0); 1007 } 1008 1009 int 1010 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request, 1011 size_t len, struct ucred *cred) 1012 { 1013 struct sadb_x_policy *xpl; 1014 struct secpolicy **pcb_sp; 1015 1016 /* Sanity check. */ 1017 if (inp == NULL || request == NULL) 1018 return (EINVAL); 1019 if (len < sizeof(*xpl)) 1020 return (EINVAL); 1021 xpl = (struct sadb_x_policy *)request; 1022 1023 /* Select direction. */ 1024 switch (xpl->sadb_x_policy_dir) { 1025 case IPSEC_DIR_INBOUND: 1026 pcb_sp = &inp->inp_sp->sp_in; 1027 break; 1028 case IPSEC_DIR_OUTBOUND: 1029 pcb_sp = &inp->inp_sp->sp_out; 1030 break; 1031 default: 1032 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1033 xpl->sadb_x_policy_dir)); 1034 return (EINVAL); 1035 } 1036 1037 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred)); 1038 } 1039 1040 int 1041 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len, 1042 struct mbuf **mp) 1043 { 1044 struct sadb_x_policy *xpl; 1045 struct secpolicy *pcb_sp; 1046 1047 /* Sanity check. */ 1048 if (inp == NULL || request == NULL || mp == NULL) 1049 return (EINVAL); 1050 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 1051 if (len < sizeof(*xpl)) 1052 return (EINVAL); 1053 xpl = (struct sadb_x_policy *)request; 1054 1055 /* Select direction. */ 1056 switch (xpl->sadb_x_policy_dir) { 1057 case IPSEC_DIR_INBOUND: 1058 pcb_sp = inp->inp_sp->sp_in; 1059 break; 1060 case IPSEC_DIR_OUTBOUND: 1061 pcb_sp = inp->inp_sp->sp_out; 1062 break; 1063 default: 1064 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1065 xpl->sadb_x_policy_dir)); 1066 return (EINVAL); 1067 } 1068 1069 /* Sanity check. Should be an IPSEC_ASSERT. */ 1070 if (pcb_sp == NULL) 1071 return (EINVAL); 1072 1073 *mp = key_sp2msg(pcb_sp); 1074 if (!*mp) { 1075 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 1076 return (ENOBUFS); 1077 } 1078 1079 (*mp)->m_type = MT_DATA; 1080 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1081 printf("%s:\n", __func__); kdebug_mbuf(*mp)); 1082 1083 return (0); 1084 } 1085 1086 /* Delete policy in PCB. */ 1087 int 1088 ipsec_delete_pcbpolicy(struct inpcb *inp) 1089 { 1090 IPSEC_ASSERT(inp != NULL, ("null inp")); 1091 1092 if (inp->inp_sp == NULL) 1093 return (0); 1094 1095 if (inp->inp_sp->sp_in != NULL) 1096 KEY_FREESP(&inp->inp_sp->sp_in); 1097 1098 if (inp->inp_sp->sp_out != NULL) 1099 KEY_FREESP(&inp->inp_sp->sp_out); 1100 1101 ipsec_delpcbpolicy(inp->inp_sp); 1102 inp->inp_sp = NULL; 1103 1104 return (0); 1105 } 1106 1107 /* 1108 * Return current level. 1109 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1110 */ 1111 u_int 1112 ipsec_get_reqlevel(struct ipsecrequest *isr) 1113 { 1114 u_int level = 0; 1115 u_int esp_trans_deflev, esp_net_deflev; 1116 u_int ah_trans_deflev, ah_net_deflev; 1117 1118 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument")); 1119 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1120 ("af family mismatch, src %u, dst %u", 1121 isr->sp->spidx.src.sa.sa_family, 1122 isr->sp->spidx.dst.sa.sa_family)); 1123 1124 /* XXX Note that we have ipseclog() expanded here - code sync issue. */ 1125 #define IPSEC_CHECK_DEFAULT(lev) \ 1126 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1127 && (lev) != IPSEC_LEVEL_UNIQUE) \ 1128 ? (V_ipsec_debug \ 1129 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\ 1130 (lev), IPSEC_LEVEL_REQUIRE) \ 1131 : 0), \ 1132 (lev) = IPSEC_LEVEL_REQUIRE, \ 1133 (lev) \ 1134 : (lev)) 1135 1136 /* Set default level. */ 1137 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1138 #ifdef INET 1139 case AF_INET: 1140 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev); 1141 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev); 1142 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev); 1143 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev); 1144 break; 1145 #endif 1146 #ifdef INET6 1147 case AF_INET6: 1148 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev); 1149 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev); 1150 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev); 1151 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev); 1152 break; 1153 #endif /* INET6 */ 1154 default: 1155 panic("%s: unknown af %u", 1156 __func__, isr->sp->spidx.src.sa.sa_family); 1157 } 1158 1159 #undef IPSEC_CHECK_DEFAULT 1160 1161 /* Set level. */ 1162 switch (isr->level) { 1163 case IPSEC_LEVEL_DEFAULT: 1164 switch (isr->saidx.proto) { 1165 case IPPROTO_ESP: 1166 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1167 level = esp_net_deflev; 1168 else 1169 level = esp_trans_deflev; 1170 break; 1171 case IPPROTO_AH: 1172 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1173 level = ah_net_deflev; 1174 else 1175 level = ah_trans_deflev; 1176 break; 1177 case IPPROTO_IPCOMP: 1178 /* 1179 * We don't really care, as IPcomp document says that 1180 * we shouldn't compress small packets. 1181 */ 1182 level = IPSEC_LEVEL_USE; 1183 break; 1184 default: 1185 panic("%s: Illegal protocol defined %u\n", __func__, 1186 isr->saidx.proto); 1187 } 1188 break; 1189 1190 case IPSEC_LEVEL_USE: 1191 case IPSEC_LEVEL_REQUIRE: 1192 level = isr->level; 1193 break; 1194 case IPSEC_LEVEL_UNIQUE: 1195 level = IPSEC_LEVEL_REQUIRE; 1196 break; 1197 1198 default: 1199 panic("%s: Illegal IPsec level %u\n", __func__, isr->level); 1200 } 1201 1202 return (level); 1203 } 1204 1205 /* 1206 * Check security policy requirements against the actual 1207 * packet contents. Return one if the packet should be 1208 * reject as "invalid"; otherwiser return zero to have the 1209 * packet treated as "valid". 1210 * 1211 * OUT: 1212 * 0: valid 1213 * 1: invalid 1214 */ 1215 int 1216 ipsec_in_reject(struct secpolicy *sp, struct mbuf *m) 1217 { 1218 struct ipsecrequest *isr; 1219 int need_auth; 1220 1221 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1222 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1223 1224 /* Check policy. */ 1225 switch (sp->policy) { 1226 case IPSEC_POLICY_DISCARD: 1227 return (1); 1228 case IPSEC_POLICY_BYPASS: 1229 case IPSEC_POLICY_NONE: 1230 return (0); 1231 } 1232 1233 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1234 ("invalid policy %u", sp->policy)); 1235 1236 /* XXX Should compare policy against IPsec header history. */ 1237 1238 need_auth = 0; 1239 for (isr = sp->req; isr != NULL; isr = isr->next) { 1240 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1241 continue; 1242 switch (isr->saidx.proto) { 1243 case IPPROTO_ESP: 1244 if ((m->m_flags & M_DECRYPTED) == 0) { 1245 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1246 printf("%s: ESP m_flags:%x\n", __func__, 1247 m->m_flags)); 1248 return (1); 1249 } 1250 1251 if (!need_auth && 1252 isr->sav != NULL && 1253 isr->sav->tdb_authalgxform != NULL && 1254 (m->m_flags & M_AUTHIPDGM) == 0) { 1255 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1256 printf("%s: ESP/AH m_flags:%x\n", __func__, 1257 m->m_flags)); 1258 return (1); 1259 } 1260 break; 1261 case IPPROTO_AH: 1262 need_auth = 1; 1263 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1264 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1265 printf("%s: AH m_flags:%x\n", __func__, 1266 m->m_flags)); 1267 return (1); 1268 } 1269 break; 1270 case IPPROTO_IPCOMP: 1271 /* 1272 * We don't really care, as IPcomp document 1273 * says that we shouldn't compress small 1274 * packets. IPComp policy should always be 1275 * treated as being in "use" level. 1276 */ 1277 break; 1278 } 1279 } 1280 return (0); /* Valid. */ 1281 } 1282 1283 static int 1284 ipsec46_in_reject(struct mbuf *m, struct inpcb *inp) 1285 { 1286 struct secpolicy *sp; 1287 int error; 1288 int result; 1289 1290 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1291 1292 /* 1293 * Get SP for this packet. 1294 * When we are called from ip_forward(), we call 1295 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1296 */ 1297 if (inp == NULL) 1298 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1299 else 1300 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error); 1301 1302 if (sp != NULL) { 1303 result = ipsec_in_reject(sp, m); 1304 KEY_FREESP(&sp); 1305 } else { 1306 result = 0; /* XXX Should be panic? 1307 * -> No, there may be error. */ 1308 } 1309 return (result); 1310 } 1311 1312 /* 1313 * Check AH/ESP integrity. 1314 * This function is called from tcp_input(), udp_input(), 1315 * and {ah,esp}4_input for tunnel mode. 1316 */ 1317 int 1318 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1319 { 1320 int result; 1321 1322 result = ipsec46_in_reject(m, inp); 1323 if (result) 1324 IPSECSTAT_INC(ips_in_polvio); 1325 1326 return (result); 1327 } 1328 1329 #ifdef INET6 1330 /* 1331 * Check AH/ESP integrity. 1332 * This function is called from tcp6_input(), udp6_input(), 1333 * and {ah,esp}6_input for tunnel mode. 1334 */ 1335 int 1336 ipsec6_in_reject(struct mbuf *m, struct inpcb *inp) 1337 { 1338 int result; 1339 1340 result = ipsec46_in_reject(m, inp); 1341 if (result) 1342 IPSEC6STAT_INC(ips_in_polvio); 1343 1344 return (result); 1345 } 1346 #endif 1347 1348 /* 1349 * Compute the byte size to be occupied by IPsec header. 1350 * In case it is tunnelled, it includes the size of outer IP header. 1351 * NOTE: SP passed is freed in this function. 1352 */ 1353 static size_t 1354 ipsec_hdrsiz_internal(struct secpolicy *sp) 1355 { 1356 struct ipsecrequest *isr; 1357 size_t size; 1358 1359 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1360 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1361 1362 switch (sp->policy) { 1363 case IPSEC_POLICY_DISCARD: 1364 case IPSEC_POLICY_BYPASS: 1365 case IPSEC_POLICY_NONE: 1366 return (0); 1367 } 1368 1369 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1370 ("invalid policy %u", sp->policy)); 1371 1372 size = 0; 1373 for (isr = sp->req; isr != NULL; isr = isr->next) { 1374 size_t clen = 0; 1375 1376 switch (isr->saidx.proto) { 1377 case IPPROTO_ESP: 1378 clen = esp_hdrsiz(isr->sav); 1379 break; 1380 case IPPROTO_AH: 1381 clen = ah_hdrsiz(isr->sav); 1382 break; 1383 case IPPROTO_IPCOMP: 1384 clen = sizeof(struct ipcomp); 1385 break; 1386 } 1387 1388 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1389 switch (isr->saidx.dst.sa.sa_family) { 1390 case AF_INET: 1391 clen += sizeof(struct ip); 1392 break; 1393 #ifdef INET6 1394 case AF_INET6: 1395 clen += sizeof(struct ip6_hdr); 1396 break; 1397 #endif 1398 default: 1399 ipseclog((LOG_ERR, "%s: unknown AF %d in " 1400 "IPsec tunnel SA\n", __func__, 1401 ((struct sockaddr *)&isr->saidx.dst)->sa_family)); 1402 break; 1403 } 1404 } 1405 size += clen; 1406 } 1407 1408 return (size); 1409 } 1410 1411 /* 1412 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(), 1413 * disabled ip6_ipsec_mtu() and ip6_forward(). 1414 */ 1415 size_t 1416 ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1417 { 1418 struct secpolicy *sp; 1419 int error; 1420 size_t size; 1421 1422 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1423 1424 /* Get SP for this packet. 1425 * When we are called from ip_forward(), we call 1426 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1427 */ 1428 if (inp == NULL) 1429 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1430 else 1431 sp = ipsec_getpolicybysock(m, dir, inp, &error); 1432 1433 if (sp != NULL) { 1434 size = ipsec_hdrsiz_internal(sp); 1435 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1436 printf("%s: size:%lu.\n", __func__, 1437 (unsigned long)size)); 1438 1439 KEY_FREESP(&sp); 1440 } else { 1441 size = 0; /* XXX Should be panic? 1442 * -> No, we are called w/o knowing if 1443 * IPsec processing is needed. */ 1444 } 1445 return (size); 1446 } 1447 1448 /* 1449 * Check the variable replay window. 1450 * ipsec_chkreplay() performs replay check before ICV verification. 1451 * ipsec_updatereplay() updates replay bitmap. This must be called after 1452 * ICV verification (it also performs replay check, which is usually done 1453 * beforehand). 1454 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1455 * 1456 * Based on RFC 2401. 1457 */ 1458 int 1459 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav) 1460 { 1461 const struct secreplay *replay; 1462 u_int32_t diff; 1463 int fr; 1464 u_int32_t wsizeb; /* Constant: bits of window size. */ 1465 int frlast; /* Constant: last frame. */ 1466 1467 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1468 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1469 1470 replay = sav->replay; 1471 1472 if (replay->wsize == 0) 1473 return (1); /* No need to check replay. */ 1474 1475 /* Constant. */ 1476 frlast = replay->wsize - 1; 1477 wsizeb = replay->wsize << 3; 1478 1479 /* Sequence number of 0 is invalid. */ 1480 if (seq == 0) 1481 return (0); 1482 1483 /* First time is always okay. */ 1484 if (replay->count == 0) 1485 return (1); 1486 1487 if (seq > replay->lastseq) { 1488 /* Larger sequences are okay. */ 1489 return (1); 1490 } else { 1491 /* seq is equal or less than lastseq. */ 1492 diff = replay->lastseq - seq; 1493 1494 /* Over range to check, i.e. too old or wrapped. */ 1495 if (diff >= wsizeb) 1496 return (0); 1497 1498 fr = frlast - diff / 8; 1499 1500 /* This packet already seen? */ 1501 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1502 return (0); 1503 1504 /* Out of order but good. */ 1505 return (1); 1506 } 1507 } 1508 1509 /* 1510 * Check replay counter whether to update or not. 1511 * OUT: 0: OK 1512 * 1: NG 1513 */ 1514 int 1515 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav) 1516 { 1517 struct secreplay *replay; 1518 u_int32_t diff; 1519 int fr; 1520 u_int32_t wsizeb; /* Constant: bits of window size. */ 1521 int frlast; /* Constant: last frame. */ 1522 1523 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1524 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1525 1526 replay = sav->replay; 1527 1528 if (replay->wsize == 0) 1529 goto ok; /* No need to check replay. */ 1530 1531 /* Constant. */ 1532 frlast = replay->wsize - 1; 1533 wsizeb = replay->wsize << 3; 1534 1535 /* Sequence number of 0 is invalid. */ 1536 if (seq == 0) 1537 return (1); 1538 1539 /* First time. */ 1540 if (replay->count == 0) { 1541 replay->lastseq = seq; 1542 bzero(replay->bitmap, replay->wsize); 1543 (replay->bitmap)[frlast] = 1; 1544 goto ok; 1545 } 1546 1547 if (seq > replay->lastseq) { 1548 /* seq is larger than lastseq. */ 1549 diff = seq - replay->lastseq; 1550 1551 /* New larger sequence number. */ 1552 if (diff < wsizeb) { 1553 /* In window. */ 1554 /* Set bit for this packet. */ 1555 vshiftl(replay->bitmap, diff, replay->wsize); 1556 (replay->bitmap)[frlast] |= 1; 1557 } else { 1558 /* This packet has a "way larger". */ 1559 bzero(replay->bitmap, replay->wsize); 1560 (replay->bitmap)[frlast] = 1; 1561 } 1562 replay->lastseq = seq; 1563 1564 /* Larger is good. */ 1565 } else { 1566 /* seq is equal or less than lastseq. */ 1567 diff = replay->lastseq - seq; 1568 1569 /* Over range to check, i.e. too old or wrapped. */ 1570 if (diff >= wsizeb) 1571 return (1); 1572 1573 fr = frlast - diff / 8; 1574 1575 /* This packet already seen? */ 1576 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1577 return (1); 1578 1579 /* Mark as seen. */ 1580 (replay->bitmap)[fr] |= (1 << (diff % 8)); 1581 1582 /* Out of order but good. */ 1583 } 1584 1585 ok: 1586 if (replay->count == ~0) { 1587 1588 /* Set overflow flag. */ 1589 replay->overflow++; 1590 1591 /* Don't increment, no more packets accepted. */ 1592 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 1593 return (1); 1594 1595 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1596 __func__, replay->overflow, ipsec_logsastr(sav))); 1597 } 1598 1599 replay->count++; 1600 1601 return (0); 1602 } 1603 1604 /* 1605 * Shift variable length buffer to left. 1606 * IN: bitmap: pointer to the buffer 1607 * nbit: the number of to shift. 1608 * wsize: buffer size (bytes). 1609 */ 1610 static void 1611 vshiftl(unsigned char *bitmap, int nbit, int wsize) 1612 { 1613 int s, j, i; 1614 unsigned char over; 1615 1616 for (j = 0; j < nbit; j += 8) { 1617 s = (nbit - j < 8) ? (nbit - j): 8; 1618 bitmap[0] <<= s; 1619 for (i = 1; i < wsize; i++) { 1620 over = (bitmap[i] >> (8 - s)); 1621 bitmap[i] <<= s; 1622 bitmap[i-1] |= over; 1623 } 1624 } 1625 } 1626 1627 #ifdef INET 1628 /* Return a printable string for the IPv4 address. */ 1629 static char * 1630 inet_ntoa4(struct in_addr ina) 1631 { 1632 static char buf[4][4 * sizeof "123" + 4]; 1633 unsigned char *ucp = (unsigned char *) &ina; 1634 static int i = 3; 1635 1636 /* XXX-BZ Returns static buffer. */ 1637 i = (i + 1) % 4; 1638 sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff, 1639 ucp[2] & 0xff, ucp[3] & 0xff); 1640 return (buf[i]); 1641 } 1642 #endif 1643 1644 /* Return a printable string for the address. */ 1645 char * 1646 ipsec_address(union sockaddr_union* sa) 1647 { 1648 #ifdef INET6 1649 char ip6buf[INET6_ADDRSTRLEN]; 1650 #endif 1651 1652 switch (sa->sa.sa_family) { 1653 #ifdef INET 1654 case AF_INET: 1655 return (inet_ntoa4(sa->sin.sin_addr)); 1656 #endif /* INET */ 1657 #ifdef INET6 1658 case AF_INET6: 1659 return (ip6_sprintf(ip6buf, &sa->sin6.sin6_addr)); 1660 #endif /* INET6 */ 1661 default: 1662 return ("(unknown address family)"); 1663 } 1664 } 1665 1666 const char * 1667 ipsec_logsastr(struct secasvar *sav) 1668 { 1669 static char buf[256]; 1670 char *p; 1671 struct secasindex *saidx = &sav->sah->saidx; 1672 1673 IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 1674 ("address family mismatch")); 1675 1676 p = buf; 1677 snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi)); 1678 while (p && *p) 1679 p++; 1680 /* NB: only use ipsec_address on one address at a time. */ 1681 snprintf(p, sizeof (buf) - (p - buf), "src=%s ", 1682 ipsec_address(&saidx->src)); 1683 while (p && *p) 1684 p++; 1685 snprintf(p, sizeof (buf) - (p - buf), "dst=%s)", 1686 ipsec_address(&saidx->dst)); 1687 1688 return (buf); 1689 } 1690 1691 void 1692 ipsec_dumpmbuf(struct mbuf *m) 1693 { 1694 int totlen; 1695 int i; 1696 u_char *p; 1697 1698 totlen = 0; 1699 printf("---\n"); 1700 while (m) { 1701 p = mtod(m, u_char *); 1702 for (i = 0; i < m->m_len; i++) { 1703 printf("%02x ", p[i]); 1704 totlen++; 1705 if (totlen % 16 == 0) 1706 printf("\n"); 1707 } 1708 m = m->m_next; 1709 } 1710 if (totlen % 16 != 0) 1711 printf("\n"); 1712 printf("---\n"); 1713 } 1714 1715 static void 1716 ipsec_init(const void *unused __unused) 1717 { 1718 1719 SECPOLICY_LOCK_INIT(&V_ip4_def_policy); 1720 V_ip4_def_policy.refcnt = 1; /* NB: disallow free. */ 1721 } 1722 VNET_SYSINIT(ipsec_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, ipsec_init, 1723 NULL); 1724 1725 1726 /* XXX This stuff doesn't belong here... */ 1727 1728 static struct xformsw* xforms = NULL; 1729 1730 /* 1731 * Register a transform; typically at system startup. 1732 */ 1733 void 1734 xform_register(struct xformsw* xsp) 1735 { 1736 1737 xsp->xf_next = xforms; 1738 xforms = xsp; 1739 } 1740 1741 /* 1742 * Initialize transform support in an sav. 1743 */ 1744 int 1745 xform_init(struct secasvar *sav, int xftype) 1746 { 1747 struct xformsw *xsp; 1748 1749 if (sav->tdb_xform != NULL) /* Previously initialized. */ 1750 return (0); 1751 for (xsp = xforms; xsp; xsp = xsp->xf_next) 1752 if (xsp->xf_type == xftype) 1753 return ((*xsp->xf_init)(sav, xsp)); 1754 return (EINVAL); 1755 } 1756