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