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 /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 122 VNET_DEFINE(int, ip4_ipsec_ecn) = 0; 123 VNET_DEFINE(int, ip4_esp_randpad) = -1; 124 125 static VNET_DEFINE(struct secpolicy, def_policy); 126 #define V_def_policy VNET(def_policy) 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_INT(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy, 145 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(def_policy).policy, 0, 146 "IPsec default policy."); 147 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev, 148 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_esp_trans_deflev), 0, 149 "Default ESP transport mode level"); 150 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev, 151 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_esp_net_deflev), 0, 152 "Default ESP tunnel mode level."); 153 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev, 154 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ah_trans_deflev), 0, 155 "AH transfer mode default level."); 156 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev, 157 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ah_net_deflev), 0, 158 "AH tunnel mode default level."); 159 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos, 160 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ah_cleartos), 0, 161 "If set clear type-of-service field when doing AH computation."); 162 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, ah_offsetmask, 163 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ah_offsetmask), 0, 164 "If not set clear offset field mask when doing AH computation."); 165 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit, 166 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ipsec_dfbit), 0, 167 "Do not fragment bit on encap."); 168 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn, 169 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ipsec_ecn), 0, 170 "Explicit Congestion Notification handling."); 171 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEBUG, debug, 172 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0, 173 "Enable IPsec debugging output when set."); 174 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, crypto_support, 175 CTLFLAG_VNET | 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_INT(_net_inet_ipsec, OID_AUTO, test_replay, 187 CTLFLAG_VNET | 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_INT(_net_inet_ipsec, OID_AUTO, test_integrity, 195 CTLFLAG_VNET | 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_INT(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy, 217 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(def_policy).policy, 0, 218 "IPsec default policy."); 219 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev, 220 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_esp_trans_deflev), 0, 221 "Default ESP transport mode level."); 222 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev, 223 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_esp_net_deflev), 0, 224 "Default ESP tunnel mode level."); 225 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev, 226 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ah_trans_deflev), 0, 227 "AH transfer mode default level."); 228 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev, 229 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ah_net_deflev), 0, 230 "AH tunnel mode default level."); 231 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_ECN, ecn, 232 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ipsec_ecn), 0, 233 "Explicit Congestion Notification handling."); 234 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEBUG, debug, 235 CTLFLAG_VNET | CTLFLAG_RW, &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_in_reject(struct secpolicy *, struct mbuf *); 242 static int ipsec_setspidx_inpcb(struct mbuf *, struct inpcb *); 243 static int ipsec_setspidx(struct mbuf *, struct secpolicyindex *, int); 244 static void ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *, int); 245 static int ipsec4_setspidx_ipaddr(struct mbuf *, struct secpolicyindex *); 246 #ifdef INET6 247 static void ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *, int); 248 static int ipsec6_setspidx_ipaddr(struct mbuf *, struct secpolicyindex *); 249 #endif 250 static void ipsec_delpcbpolicy(struct inpcbpolicy *); 251 static struct secpolicy *ipsec_deepcopy_policy(struct secpolicy *src); 252 static void vshiftl(unsigned char *, int, int); 253 254 MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy"); 255 256 /* 257 * Return a held reference to the default SP. 258 */ 259 static struct secpolicy * 260 key_allocsp_default(const char* where, int tag) 261 { 262 struct secpolicy *sp; 263 264 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 265 printf("DP key_allocsp_default from %s:%u\n", where, tag)); 266 267 sp = &V_def_policy; 268 if (sp->policy != IPSEC_POLICY_DISCARD && 269 sp->policy != IPSEC_POLICY_NONE) { 270 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n", 271 sp->policy, IPSEC_POLICY_NONE)); 272 sp->policy = IPSEC_POLICY_NONE; 273 } 274 key_addref(sp); 275 276 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 277 printf("DP key_allocsp_default returns SP:%p (%u)\n", 278 sp, sp->refcnt)); 279 return (sp); 280 } 281 #define KEY_ALLOCSP_DEFAULT() \ 282 key_allocsp_default(__FILE__, __LINE__) 283 284 /* 285 * For OUTBOUND packet having a socket. Searching SPD for packet, 286 * and return a pointer to SP. 287 * OUT: NULL: no apropreate SP found, the following value is set to error. 288 * 0 : bypass 289 * EACCES : discard packet. 290 * ENOENT : ipsec_acquire() in progress, maybe. 291 * others : error occured. 292 * others: a pointer to SP 293 * 294 * NOTE: IPv6 mapped adddress concern is implemented here. 295 */ 296 struct secpolicy * 297 ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir) 298 { 299 struct secpolicy *sp; 300 301 IPSEC_ASSERT(tdbi != NULL, ("null tdbi")); 302 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 303 ("invalid direction %u", dir)); 304 305 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir); 306 if (sp == NULL) /*XXX????*/ 307 sp = KEY_ALLOCSP_DEFAULT(); 308 IPSEC_ASSERT(sp != NULL, ("null SP")); 309 return (sp); 310 } 311 312 /* 313 * For OUTBOUND packet having a socket. Searching SPD for packet, 314 * and return a pointer to SP. 315 * OUT: NULL: no apropreate SP found, the following value is set to error. 316 * 0 : bypass 317 * EACCES : discard packet. 318 * ENOENT : ipsec_acquire() in progress, maybe. 319 * others : error occured. 320 * others: a pointer to SP 321 * 322 * NOTE: IPv6 mapped adddress concern is implemented here. 323 */ 324 static struct secpolicy * 325 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb *inp, int *error) 326 { 327 struct inpcbpolicy *pcbsp; 328 struct secpolicy *currsp = NULL; /* Policy on socket. */ 329 struct secpolicy *sp; 330 331 IPSEC_ASSERT(m != NULL, ("null mbuf")); 332 IPSEC_ASSERT(inp != NULL, ("null inpcb")); 333 IPSEC_ASSERT(error != NULL, ("null error")); 334 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 335 ("invalid direction %u", dir)); 336 337 if (!key_havesp(dir)) { 338 /* No SP found, use system default. */ 339 sp = KEY_ALLOCSP_DEFAULT(); 340 return (sp); 341 } 342 343 /* Set spidx in pcb. */ 344 *error = ipsec_setspidx_inpcb(m, inp); 345 if (*error) 346 return (NULL); 347 348 pcbsp = inp->inp_sp; 349 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp")); 350 switch (dir) { 351 case IPSEC_DIR_INBOUND: 352 currsp = pcbsp->sp_in; 353 break; 354 case IPSEC_DIR_OUTBOUND: 355 currsp = pcbsp->sp_out; 356 break; 357 } 358 IPSEC_ASSERT(currsp != NULL, ("null currsp")); 359 360 if (pcbsp->priv) { /* When privilieged socket. */ 361 switch (currsp->policy) { 362 case IPSEC_POLICY_BYPASS: 363 case IPSEC_POLICY_IPSEC: 364 key_addref(currsp); 365 sp = currsp; 366 break; 367 368 case IPSEC_POLICY_ENTRUST: 369 /* Look for a policy in SPD. */ 370 sp = KEY_ALLOCSP(&currsp->spidx, dir); 371 if (sp == NULL) /* No SP found. */ 372 sp = KEY_ALLOCSP_DEFAULT(); 373 break; 374 375 default: 376 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n", 377 __func__, currsp->policy)); 378 *error = EINVAL; 379 return (NULL); 380 } 381 } else { /* Unpriv, SPD has policy. */ 382 sp = KEY_ALLOCSP(&currsp->spidx, dir); 383 if (sp == NULL) { /* No SP found. */ 384 switch (currsp->policy) { 385 case IPSEC_POLICY_BYPASS: 386 ipseclog((LOG_ERR, "%s: Illegal policy for " 387 "non-priviliged defined %d\n", 388 __func__, currsp->policy)); 389 *error = EINVAL; 390 return (NULL); 391 392 case IPSEC_POLICY_ENTRUST: 393 sp = KEY_ALLOCSP_DEFAULT(); 394 break; 395 396 case IPSEC_POLICY_IPSEC: 397 key_addref(currsp); 398 sp = currsp; 399 break; 400 401 default: 402 ipseclog((LOG_ERR, "%s: Invalid policy for " 403 "PCB %d\n", __func__, currsp->policy)); 404 *error = EINVAL; 405 return (NULL); 406 } 407 } 408 } 409 IPSEC_ASSERT(sp != NULL, 410 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy)); 411 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 412 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n", 413 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt)); 414 return (sp); 415 } 416 417 /* 418 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 419 * and return a pointer to SP. 420 * OUT: positive: a pointer to the entry for security policy leaf matched. 421 * NULL: no apropreate SP found, the following value is set to error. 422 * 0 : bypass 423 * EACCES : discard packet. 424 * ENOENT : ipsec_acquire() in progress, maybe. 425 * others : error occured. 426 */ 427 struct secpolicy * 428 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int *error) 429 { 430 struct secpolicyindex spidx; 431 struct secpolicy *sp; 432 433 IPSEC_ASSERT(m != NULL, ("null mbuf")); 434 IPSEC_ASSERT(error != NULL, ("null error")); 435 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 436 ("invalid direction %u", dir)); 437 438 sp = NULL; 439 *error = 0; 440 if (key_havesp(dir)) { 441 /* Make an index to look for a policy. */ 442 *error = ipsec_setspidx(m, &spidx, 0); 443 if (*error != 0) { 444 DPRINTF(("%s: setpidx failed, dir %u\n", 445 __func__, dir)); 446 return (NULL); 447 } 448 spidx.dir = dir; 449 sp = KEY_ALLOCSP(&spidx, dir); 450 } 451 if (sp == NULL) /* No SP found, use system default. */ 452 sp = KEY_ALLOCSP_DEFAULT(); 453 IPSEC_ASSERT(sp != NULL, ("null SP")); 454 return (sp); 455 } 456 457 struct secpolicy * 458 ipsec4_checkpolicy(struct mbuf *m, u_int dir, int *error, struct inpcb *inp) 459 { 460 struct secpolicy *sp; 461 462 *error = 0; 463 if (inp == NULL) 464 sp = ipsec_getpolicybyaddr(m, dir, error); 465 else 466 sp = ipsec_getpolicybysock(m, dir, inp, error); 467 if (sp == NULL) { 468 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error")); 469 IPSECSTAT_INC(ips_out_inval); 470 return (NULL); 471 } 472 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error)); 473 switch (sp->policy) { 474 case IPSEC_POLICY_ENTRUST: 475 default: 476 printf("%s: invalid policy %u\n", __func__, sp->policy); 477 /* FALLTHROUGH */ 478 case IPSEC_POLICY_DISCARD: 479 IPSECSTAT_INC(ips_out_polvio); 480 *error = -EINVAL; /* Packet is discarded by caller. */ 481 break; 482 case IPSEC_POLICY_BYPASS: 483 case IPSEC_POLICY_NONE: 484 KEY_FREESP(&sp); 485 sp = NULL; /* NB: force NULL result. */ 486 break; 487 case IPSEC_POLICY_IPSEC: 488 if (sp->req == NULL) /* Acquire a SA. */ 489 *error = key_spdacquire(sp); 490 break; 491 } 492 if (*error != 0) { 493 KEY_FREESP(&sp); 494 sp = NULL; 495 } 496 return (sp); 497 } 498 499 static int 500 ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp) 501 { 502 int error; 503 504 IPSEC_ASSERT(inp != NULL, ("null inp")); 505 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 506 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL, 507 ("null sp_in || sp_out")); 508 509 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1); 510 if (error == 0) { 511 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 512 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx; 513 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 514 } else { 515 bzero(&inp->inp_sp->sp_in->spidx, 516 sizeof (inp->inp_sp->sp_in->spidx)); 517 bzero(&inp->inp_sp->sp_out->spidx, 518 sizeof (inp->inp_sp->sp_in->spidx)); 519 } 520 return (error); 521 } 522 523 /* 524 * Configure security policy index (src/dst/proto/sport/dport) 525 * by looking at the content of mbuf. 526 * The caller is responsible for error recovery (like clearing up spidx). 527 */ 528 static int 529 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 530 { 531 struct ip *ip = NULL; 532 struct ip ipbuf; 533 u_int v; 534 struct mbuf *n; 535 int len; 536 int error; 537 538 IPSEC_ASSERT(m != NULL, ("null mbuf")); 539 540 /* 541 * Validate m->m_pkthdr.len. We see incorrect length if we 542 * mistakenly call this function with inconsistent mbuf chain 543 * (like 4.4BSD tcp/udp processing). XXX Should we panic here? 544 */ 545 len = 0; 546 for (n = m; n; n = n->m_next) 547 len += n->m_len; 548 if (m->m_pkthdr.len != len) { 549 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 550 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n", 551 __func__, len, m->m_pkthdr.len)); 552 return (EINVAL); 553 } 554 555 if (m->m_pkthdr.len < sizeof(struct ip)) { 556 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 557 printf("%s: pkthdr len(%d) too small (v4), ignored.\n", 558 __func__, m->m_pkthdr.len)); 559 return (EINVAL); 560 } 561 562 if (m->m_len >= sizeof(*ip)) 563 ip = mtod(m, struct ip *); 564 else { 565 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf); 566 ip = &ipbuf; 567 } 568 v = ip->ip_v; 569 switch (v) { 570 case 4: 571 error = ipsec4_setspidx_ipaddr(m, spidx); 572 if (error) 573 return (error); 574 ipsec4_get_ulp(m, spidx, needport); 575 return (0); 576 #ifdef INET6 577 case 6: 578 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 579 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 580 printf("%s: pkthdr len(%d) too small (v6), " 581 "ignored\n", __func__, m->m_pkthdr.len)); 582 return (EINVAL); 583 } 584 error = ipsec6_setspidx_ipaddr(m, spidx); 585 if (error) 586 return (error); 587 ipsec6_get_ulp(m, spidx, needport); 588 return (0); 589 #endif 590 default: 591 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 592 printf("%s: " "unknown IP version %u, ignored.\n", 593 __func__, v)); 594 return (EINVAL); 595 } 596 } 597 598 static void 599 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 600 { 601 u_int8_t nxt; 602 int off; 603 604 /* Sanity check. */ 605 IPSEC_ASSERT(m != NULL, ("null mbuf")); 606 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short")); 607 608 if (m->m_len >= sizeof (struct ip)) { 609 struct ip *ip = mtod(m, struct ip *); 610 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 611 goto done; 612 off = ip->ip_hl << 2; 613 nxt = ip->ip_p; 614 } else { 615 struct ip ih; 616 617 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih); 618 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 619 goto done; 620 off = ih.ip_hl << 2; 621 nxt = ih.ip_p; 622 } 623 624 while (off < m->m_pkthdr.len) { 625 struct ip6_ext ip6e; 626 struct tcphdr th; 627 struct udphdr uh; 628 629 switch (nxt) { 630 case IPPROTO_TCP: 631 spidx->ul_proto = nxt; 632 if (!needport) 633 goto done_proto; 634 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 635 goto done; 636 m_copydata(m, off, sizeof (th), (caddr_t) &th); 637 spidx->src.sin.sin_port = th.th_sport; 638 spidx->dst.sin.sin_port = th.th_dport; 639 return; 640 case IPPROTO_UDP: 641 spidx->ul_proto = nxt; 642 if (!needport) 643 goto done_proto; 644 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 645 goto done; 646 m_copydata(m, off, sizeof (uh), (caddr_t) &uh); 647 spidx->src.sin.sin_port = uh.uh_sport; 648 spidx->dst.sin.sin_port = uh.uh_dport; 649 return; 650 case IPPROTO_AH: 651 if (off + sizeof(ip6e) > m->m_pkthdr.len) 652 goto done; 653 /* XXX Sigh, this works but is totally bogus. */ 654 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e); 655 off += (ip6e.ip6e_len + 2) << 2; 656 nxt = ip6e.ip6e_nxt; 657 break; 658 case IPPROTO_ICMP: 659 default: 660 /* XXX Intermediate headers??? */ 661 spidx->ul_proto = nxt; 662 goto done_proto; 663 } 664 } 665 done: 666 spidx->ul_proto = IPSEC_ULPROTO_ANY; 667 done_proto: 668 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 669 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 670 } 671 672 /* Assumes that m is sane. */ 673 static int 674 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 675 { 676 static const struct sockaddr_in template = { 677 sizeof (struct sockaddr_in), 678 AF_INET, 679 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 680 }; 681 682 spidx->src.sin = template; 683 spidx->dst.sin = template; 684 685 if (m->m_len < sizeof (struct ip)) { 686 m_copydata(m, offsetof(struct ip, ip_src), 687 sizeof (struct in_addr), 688 (caddr_t) &spidx->src.sin.sin_addr); 689 m_copydata(m, offsetof(struct ip, ip_dst), 690 sizeof (struct in_addr), 691 (caddr_t) &spidx->dst.sin.sin_addr); 692 } else { 693 struct ip *ip = mtod(m, struct ip *); 694 spidx->src.sin.sin_addr = ip->ip_src; 695 spidx->dst.sin.sin_addr = ip->ip_dst; 696 } 697 698 spidx->prefs = sizeof(struct in_addr) << 3; 699 spidx->prefd = sizeof(struct in_addr) << 3; 700 701 return (0); 702 } 703 704 #ifdef INET6 705 static void 706 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 707 { 708 int off, nxt; 709 struct tcphdr th; 710 struct udphdr uh; 711 struct icmp6_hdr ih; 712 713 /* Sanity check. */ 714 if (m == NULL) 715 panic("%s: NULL pointer was passed.\n", __func__); 716 717 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 718 printf("%s:\n", __func__); kdebug_mbuf(m)); 719 720 /* Set default. */ 721 spidx->ul_proto = IPSEC_ULPROTO_ANY; 722 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 723 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 724 725 nxt = -1; 726 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 727 if (off < 0 || m->m_pkthdr.len < off) 728 return; 729 730 switch (nxt) { 731 case IPPROTO_TCP: 732 spidx->ul_proto = nxt; 733 if (!needport) 734 break; 735 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 736 break; 737 m_copydata(m, off, sizeof(th), (caddr_t)&th); 738 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 739 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 740 break; 741 case IPPROTO_UDP: 742 spidx->ul_proto = nxt; 743 if (!needport) 744 break; 745 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 746 break; 747 m_copydata(m, off, sizeof(uh), (caddr_t)&uh); 748 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 749 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 750 break; 751 case IPPROTO_ICMPV6: 752 spidx->ul_proto = nxt; 753 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 754 break; 755 m_copydata(m, off, sizeof(ih), (caddr_t)&ih); 756 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 757 htons((uint16_t)ih.icmp6_type); 758 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 759 htons((uint16_t)ih.icmp6_code); 760 break; 761 default: 762 /* XXX Intermediate headers??? */ 763 spidx->ul_proto = nxt; 764 break; 765 } 766 } 767 768 /* Assumes that m is sane. */ 769 static int 770 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 771 { 772 struct ip6_hdr *ip6 = NULL; 773 struct ip6_hdr ip6buf; 774 struct sockaddr_in6 *sin6; 775 776 if (m->m_len >= sizeof(*ip6)) 777 ip6 = mtod(m, struct ip6_hdr *); 778 else { 779 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf); 780 ip6 = &ip6buf; 781 } 782 783 sin6 = (struct sockaddr_in6 *)&spidx->src; 784 bzero(sin6, sizeof(*sin6)); 785 sin6->sin6_family = AF_INET6; 786 sin6->sin6_len = sizeof(struct sockaddr_in6); 787 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src)); 788 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 789 sin6->sin6_addr.s6_addr16[1] = 0; 790 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 791 } 792 spidx->prefs = sizeof(struct in6_addr) << 3; 793 794 sin6 = (struct sockaddr_in6 *)&spidx->dst; 795 bzero(sin6, sizeof(*sin6)); 796 sin6->sin6_family = AF_INET6; 797 sin6->sin6_len = sizeof(struct sockaddr_in6); 798 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst)); 799 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 800 sin6->sin6_addr.s6_addr16[1] = 0; 801 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 802 } 803 spidx->prefd = sizeof(struct in6_addr) << 3; 804 805 return (0); 806 } 807 #endif 808 809 static void 810 ipsec_delpcbpolicy(struct inpcbpolicy *p) 811 { 812 813 free(p, M_IPSEC_INPCB); 814 } 815 816 /* Initialize policy in PCB. */ 817 int 818 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp) 819 { 820 struct inpcbpolicy *new; 821 822 /* Sanity check. */ 823 if (so == NULL || pcb_sp == NULL) 824 panic("%s: NULL pointer was passed.\n", __func__); 825 826 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy), 827 M_IPSEC_INPCB, M_NOWAIT|M_ZERO); 828 if (new == NULL) { 829 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 830 return (ENOBUFS); 831 } 832 833 new->priv = IPSEC_IS_PRIVILEGED_SO(so); 834 835 if ((new->sp_in = KEY_NEWSP()) == NULL) { 836 ipsec_delpcbpolicy(new); 837 return (ENOBUFS); 838 } 839 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 840 if ((new->sp_out = KEY_NEWSP()) == NULL) { 841 KEY_FREESP(&new->sp_in); 842 ipsec_delpcbpolicy(new); 843 return (ENOBUFS); 844 } 845 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 846 *pcb_sp = new; 847 848 return (0); 849 } 850 851 /* Copy old IPsec policy into new. */ 852 int 853 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new) 854 { 855 struct secpolicy *sp; 856 857 sp = ipsec_deepcopy_policy(old->sp_in); 858 if (sp) { 859 KEY_FREESP(&new->sp_in); 860 new->sp_in = sp; 861 } else 862 return (ENOBUFS); 863 864 sp = ipsec_deepcopy_policy(old->sp_out); 865 if (sp) { 866 KEY_FREESP(&new->sp_out); 867 new->sp_out = sp; 868 } else 869 return (ENOBUFS); 870 871 new->priv = old->priv; 872 873 return (0); 874 } 875 876 struct ipsecrequest * 877 ipsec_newisr(void) 878 { 879 struct ipsecrequest *p; 880 881 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO); 882 if (p != NULL) 883 IPSECREQUEST_LOCK_INIT(p); 884 return (p); 885 } 886 887 void 888 ipsec_delisr(struct ipsecrequest *p) 889 { 890 891 IPSECREQUEST_LOCK_DESTROY(p); 892 free(p, M_IPSEC_SR); 893 } 894 895 /* Deep-copy a policy in PCB. */ 896 static struct secpolicy * 897 ipsec_deepcopy_policy(struct secpolicy *src) 898 { 899 struct ipsecrequest *newchain = NULL; 900 struct ipsecrequest *p; 901 struct ipsecrequest **q; 902 struct ipsecrequest *r; 903 struct secpolicy *dst; 904 905 if (src == NULL) 906 return (NULL); 907 dst = KEY_NEWSP(); 908 if (dst == NULL) 909 return (NULL); 910 911 /* 912 * Deep-copy IPsec request chain. This is required since struct 913 * ipsecrequest is not reference counted. 914 */ 915 q = &newchain; 916 for (p = src->req; p; p = p->next) { 917 *q = ipsec_newisr(); 918 if (*q == NULL) 919 goto fail; 920 (*q)->saidx.proto = p->saidx.proto; 921 (*q)->saidx.mode = p->saidx.mode; 922 (*q)->level = p->level; 923 (*q)->saidx.reqid = p->saidx.reqid; 924 925 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src)); 926 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst)); 927 928 (*q)->sp = dst; 929 930 q = &((*q)->next); 931 } 932 933 dst->req = newchain; 934 dst->policy = src->policy; 935 /* Do not touch the refcnt fields. */ 936 937 return (dst); 938 939 fail: 940 for (p = newchain; p; p = r) { 941 r = p->next; 942 ipsec_delisr(p); 943 p = NULL; 944 } 945 return (NULL); 946 } 947 948 /* Set policy and IPsec request if present. */ 949 static int 950 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname, 951 caddr_t request, size_t len, struct ucred *cred) 952 { 953 struct sadb_x_policy *xpl; 954 struct secpolicy *newsp = NULL; 955 int error; 956 957 /* Sanity check. */ 958 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL) 959 return (EINVAL); 960 if (len < sizeof(*xpl)) 961 return (EINVAL); 962 xpl = (struct sadb_x_policy *)request; 963 964 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 965 printf("%s: passed policy\n", __func__); 966 kdebug_sadb_x_policy((struct sadb_ext *)xpl)); 967 968 /* Check policy type. */ 969 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */ 970 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 971 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 972 return (EINVAL); 973 974 /* Check privileged socket. */ 975 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 976 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0); 977 if (error) 978 return (EACCES); 979 } 980 981 /* Allocating new SP entry. */ 982 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 983 return (error); 984 985 /* Clear old SP and set new SP. */ 986 KEY_FREESP(pcb_sp); 987 *pcb_sp = newsp; 988 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 989 printf("%s: new policy\n", __func__); 990 kdebug_secpolicy(newsp)); 991 992 return (0); 993 } 994 995 int 996 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request, 997 size_t len, struct ucred *cred) 998 { 999 struct sadb_x_policy *xpl; 1000 struct secpolicy **pcb_sp; 1001 1002 /* Sanity check. */ 1003 if (inp == NULL || request == NULL) 1004 return (EINVAL); 1005 if (len < sizeof(*xpl)) 1006 return (EINVAL); 1007 xpl = (struct sadb_x_policy *)request; 1008 1009 /* Select direction. */ 1010 switch (xpl->sadb_x_policy_dir) { 1011 case IPSEC_DIR_INBOUND: 1012 pcb_sp = &inp->inp_sp->sp_in; 1013 break; 1014 case IPSEC_DIR_OUTBOUND: 1015 pcb_sp = &inp->inp_sp->sp_out; 1016 break; 1017 default: 1018 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1019 xpl->sadb_x_policy_dir)); 1020 return (EINVAL); 1021 } 1022 1023 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred)); 1024 } 1025 1026 int 1027 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len, 1028 struct mbuf **mp) 1029 { 1030 struct sadb_x_policy *xpl; 1031 struct secpolicy *pcb_sp; 1032 1033 /* Sanity check. */ 1034 if (inp == NULL || request == NULL || mp == NULL) 1035 return (EINVAL); 1036 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 1037 if (len < sizeof(*xpl)) 1038 return (EINVAL); 1039 xpl = (struct sadb_x_policy *)request; 1040 1041 /* Select direction. */ 1042 switch (xpl->sadb_x_policy_dir) { 1043 case IPSEC_DIR_INBOUND: 1044 pcb_sp = inp->inp_sp->sp_in; 1045 break; 1046 case IPSEC_DIR_OUTBOUND: 1047 pcb_sp = inp->inp_sp->sp_out; 1048 break; 1049 default: 1050 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1051 xpl->sadb_x_policy_dir)); 1052 return (EINVAL); 1053 } 1054 1055 /* Sanity check. Should be an IPSEC_ASSERT. */ 1056 if (pcb_sp == NULL) 1057 return (EINVAL); 1058 1059 *mp = key_sp2msg(pcb_sp); 1060 if (!*mp) { 1061 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 1062 return (ENOBUFS); 1063 } 1064 1065 (*mp)->m_type = MT_DATA; 1066 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1067 printf("%s:\n", __func__); kdebug_mbuf(*mp)); 1068 1069 return (0); 1070 } 1071 1072 /* Delete policy in PCB. */ 1073 int 1074 ipsec_delete_pcbpolicy(struct inpcb *inp) 1075 { 1076 IPSEC_ASSERT(inp != NULL, ("null inp")); 1077 1078 if (inp->inp_sp == NULL) 1079 return (0); 1080 1081 if (inp->inp_sp->sp_in != NULL) 1082 KEY_FREESP(&inp->inp_sp->sp_in); 1083 1084 if (inp->inp_sp->sp_out != NULL) 1085 KEY_FREESP(&inp->inp_sp->sp_out); 1086 1087 ipsec_delpcbpolicy(inp->inp_sp); 1088 inp->inp_sp = NULL; 1089 1090 return (0); 1091 } 1092 1093 /* 1094 * Return current level. 1095 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1096 */ 1097 u_int 1098 ipsec_get_reqlevel(struct ipsecrequest *isr) 1099 { 1100 u_int level = 0; 1101 u_int esp_trans_deflev, esp_net_deflev; 1102 u_int ah_trans_deflev, ah_net_deflev; 1103 1104 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument")); 1105 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1106 ("af family mismatch, src %u, dst %u", 1107 isr->sp->spidx.src.sa.sa_family, 1108 isr->sp->spidx.dst.sa.sa_family)); 1109 1110 /* XXX Note that we have ipseclog() expanded here - code sync issue. */ 1111 #define IPSEC_CHECK_DEFAULT(lev) \ 1112 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1113 && (lev) != IPSEC_LEVEL_UNIQUE) \ 1114 ? (V_ipsec_debug \ 1115 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\ 1116 (lev), IPSEC_LEVEL_REQUIRE) \ 1117 : 0), \ 1118 (lev) = IPSEC_LEVEL_REQUIRE, \ 1119 (lev) \ 1120 : (lev)) 1121 1122 /* Set default level. */ 1123 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1124 #ifdef INET 1125 case AF_INET: 1126 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev); 1127 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev); 1128 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev); 1129 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev); 1130 break; 1131 #endif 1132 #ifdef INET6 1133 case AF_INET6: 1134 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev); 1135 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev); 1136 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev); 1137 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev); 1138 break; 1139 #endif /* INET6 */ 1140 default: 1141 panic("%s: unknown af %u", 1142 __func__, isr->sp->spidx.src.sa.sa_family); 1143 } 1144 1145 #undef IPSEC_CHECK_DEFAULT 1146 1147 /* Set level. */ 1148 switch (isr->level) { 1149 case IPSEC_LEVEL_DEFAULT: 1150 switch (isr->saidx.proto) { 1151 case IPPROTO_ESP: 1152 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1153 level = esp_net_deflev; 1154 else 1155 level = esp_trans_deflev; 1156 break; 1157 case IPPROTO_AH: 1158 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1159 level = ah_net_deflev; 1160 else 1161 level = ah_trans_deflev; 1162 break; 1163 case IPPROTO_IPCOMP: 1164 /* 1165 * We don't really care, as IPcomp document says that 1166 * we shouldn't compress small packets. 1167 */ 1168 level = IPSEC_LEVEL_USE; 1169 break; 1170 default: 1171 panic("%s: Illegal protocol defined %u\n", __func__, 1172 isr->saidx.proto); 1173 } 1174 break; 1175 1176 case IPSEC_LEVEL_USE: 1177 case IPSEC_LEVEL_REQUIRE: 1178 level = isr->level; 1179 break; 1180 case IPSEC_LEVEL_UNIQUE: 1181 level = IPSEC_LEVEL_REQUIRE; 1182 break; 1183 1184 default: 1185 panic("%s: Illegal IPsec level %u\n", __func__, isr->level); 1186 } 1187 1188 return (level); 1189 } 1190 1191 /* 1192 * Check security policy requirements against the actual 1193 * packet contents. Return one if the packet should be 1194 * reject as "invalid"; otherwiser return zero to have the 1195 * packet treated as "valid". 1196 * 1197 * OUT: 1198 * 0: valid 1199 * 1: invalid 1200 */ 1201 static int 1202 ipsec_in_reject(struct secpolicy *sp, struct mbuf *m) 1203 { 1204 struct ipsecrequest *isr; 1205 int need_auth; 1206 1207 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1208 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1209 1210 /* Check policy. */ 1211 switch (sp->policy) { 1212 case IPSEC_POLICY_DISCARD: 1213 return (1); 1214 case IPSEC_POLICY_BYPASS: 1215 case IPSEC_POLICY_NONE: 1216 return (0); 1217 } 1218 1219 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1220 ("invalid policy %u", sp->policy)); 1221 1222 /* XXX Should compare policy against IPsec header history. */ 1223 1224 need_auth = 0; 1225 for (isr = sp->req; isr != NULL; isr = isr->next) { 1226 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1227 continue; 1228 switch (isr->saidx.proto) { 1229 case IPPROTO_ESP: 1230 if ((m->m_flags & M_DECRYPTED) == 0) { 1231 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1232 printf("%s: ESP m_flags:%x\n", __func__, 1233 m->m_flags)); 1234 return (1); 1235 } 1236 1237 if (!need_auth && 1238 isr->sav != NULL && 1239 isr->sav->tdb_authalgxform != NULL && 1240 (m->m_flags & M_AUTHIPDGM) == 0) { 1241 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1242 printf("%s: ESP/AH m_flags:%x\n", __func__, 1243 m->m_flags)); 1244 return (1); 1245 } 1246 break; 1247 case IPPROTO_AH: 1248 need_auth = 1; 1249 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1250 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1251 printf("%s: AH m_flags:%x\n", __func__, 1252 m->m_flags)); 1253 return (1); 1254 } 1255 break; 1256 case IPPROTO_IPCOMP: 1257 /* 1258 * We don't really care, as IPcomp document 1259 * says that we shouldn't compress small 1260 * packets. IPComp policy should always be 1261 * treated as being in "use" level. 1262 */ 1263 break; 1264 } 1265 } 1266 return (0); /* Valid. */ 1267 } 1268 1269 /* 1270 * Non zero return value means security policy DISCARD or policy violation. 1271 */ 1272 static int 1273 ipsec46_in_reject(struct mbuf *m, struct inpcb *inp) 1274 { 1275 struct secpolicy *sp; 1276 int error; 1277 int result; 1278 1279 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1280 1281 /* Get SP for this packet. */ 1282 if (inp == NULL) 1283 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, &error); 1284 else 1285 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error); 1286 1287 if (sp != NULL) { 1288 result = ipsec_in_reject(sp, m); 1289 KEY_FREESP(&sp); 1290 } else { 1291 result = 1; /* treat errors as policy violation */ 1292 } 1293 return (result); 1294 } 1295 1296 /* 1297 * Check AH/ESP integrity. 1298 * This function is called from tcp_input(), udp_input(), 1299 * and {ah,esp}4_input for tunnel mode. 1300 */ 1301 int 1302 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1303 { 1304 int result; 1305 1306 result = ipsec46_in_reject(m, inp); 1307 if (result) 1308 IPSECSTAT_INC(ips_in_polvio); 1309 1310 return (result); 1311 } 1312 1313 #ifdef INET6 1314 /* 1315 * Check AH/ESP integrity. 1316 * This function is called from tcp6_input(), udp6_input(), 1317 * and {ah,esp}6_input for tunnel mode. 1318 */ 1319 int 1320 ipsec6_in_reject(struct mbuf *m, struct inpcb *inp) 1321 { 1322 int result; 1323 1324 result = ipsec46_in_reject(m, inp); 1325 if (result) 1326 IPSEC6STAT_INC(ips_in_polvio); 1327 1328 return (result); 1329 } 1330 #endif 1331 1332 /* 1333 * Compute the byte size to be occupied by IPsec header. 1334 * In case it is tunnelled, it includes the size of outer IP header. 1335 * NOTE: SP passed is freed in this function. 1336 */ 1337 static size_t 1338 ipsec_hdrsiz_internal(struct secpolicy *sp) 1339 { 1340 struct ipsecrequest *isr; 1341 size_t size; 1342 1343 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1344 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1345 1346 switch (sp->policy) { 1347 case IPSEC_POLICY_DISCARD: 1348 case IPSEC_POLICY_BYPASS: 1349 case IPSEC_POLICY_NONE: 1350 return (0); 1351 } 1352 1353 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1354 ("invalid policy %u", sp->policy)); 1355 1356 size = 0; 1357 for (isr = sp->req; isr != NULL; isr = isr->next) { 1358 size_t clen = 0; 1359 1360 switch (isr->saidx.proto) { 1361 case IPPROTO_ESP: 1362 clen = esp_hdrsiz(isr->sav); 1363 break; 1364 case IPPROTO_AH: 1365 clen = ah_hdrsiz(isr->sav); 1366 break; 1367 case IPPROTO_IPCOMP: 1368 clen = sizeof(struct ipcomp); 1369 break; 1370 } 1371 1372 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1373 switch (isr->saidx.dst.sa.sa_family) { 1374 case AF_INET: 1375 clen += sizeof(struct ip); 1376 break; 1377 #ifdef INET6 1378 case AF_INET6: 1379 clen += sizeof(struct ip6_hdr); 1380 break; 1381 #endif 1382 default: 1383 ipseclog((LOG_ERR, "%s: unknown AF %d in " 1384 "IPsec tunnel SA\n", __func__, 1385 ((struct sockaddr *)&isr->saidx.dst)->sa_family)); 1386 break; 1387 } 1388 } 1389 size += clen; 1390 } 1391 1392 return (size); 1393 } 1394 1395 /* 1396 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(), 1397 * disabled ip6_ipsec_mtu() and ip6_forward(). 1398 */ 1399 size_t 1400 ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1401 { 1402 struct secpolicy *sp; 1403 int error; 1404 size_t size; 1405 1406 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1407 1408 /* Get SP for this packet. */ 1409 if (inp == NULL) 1410 sp = ipsec_getpolicybyaddr(m, dir, &error); 1411 else 1412 sp = ipsec_getpolicybysock(m, dir, inp, &error); 1413 1414 if (sp != NULL) { 1415 size = ipsec_hdrsiz_internal(sp); 1416 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1417 printf("%s: size:%lu.\n", __func__, 1418 (unsigned long)size)); 1419 1420 KEY_FREESP(&sp); 1421 } else { 1422 size = 0; /* XXX Should be panic? 1423 * -> No, we are called w/o knowing if 1424 * IPsec processing is needed. */ 1425 } 1426 return (size); 1427 } 1428 1429 /* 1430 * Check the variable replay window. 1431 * ipsec_chkreplay() performs replay check before ICV verification. 1432 * ipsec_updatereplay() updates replay bitmap. This must be called after 1433 * ICV verification (it also performs replay check, which is usually done 1434 * beforehand). 1435 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1436 * 1437 * Based on RFC 2401. 1438 */ 1439 int 1440 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav) 1441 { 1442 const struct secreplay *replay; 1443 u_int32_t diff; 1444 int fr; 1445 u_int32_t wsizeb; /* Constant: bits of window size. */ 1446 int frlast; /* Constant: last frame. */ 1447 1448 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1449 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1450 1451 replay = sav->replay; 1452 1453 if (replay->wsize == 0) 1454 return (1); /* No need to check replay. */ 1455 1456 /* Constant. */ 1457 frlast = replay->wsize - 1; 1458 wsizeb = replay->wsize << 3; 1459 1460 /* Sequence number of 0 is invalid. */ 1461 if (seq == 0) 1462 return (0); 1463 1464 /* First time is always okay. */ 1465 if (replay->count == 0) 1466 return (1); 1467 1468 if (seq > replay->lastseq) { 1469 /* Larger sequences are okay. */ 1470 return (1); 1471 } else { 1472 /* seq is equal or less than lastseq. */ 1473 diff = replay->lastseq - seq; 1474 1475 /* Over range to check, i.e. too old or wrapped. */ 1476 if (diff >= wsizeb) 1477 return (0); 1478 1479 fr = frlast - diff / 8; 1480 1481 /* This packet already seen? */ 1482 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1483 return (0); 1484 1485 /* Out of order but good. */ 1486 return (1); 1487 } 1488 } 1489 1490 /* 1491 * Check replay counter whether to update or not. 1492 * OUT: 0: OK 1493 * 1: NG 1494 */ 1495 int 1496 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav) 1497 { 1498 char buf[128]; 1499 struct secreplay *replay; 1500 u_int32_t diff; 1501 int fr; 1502 u_int32_t wsizeb; /* Constant: bits of window size. */ 1503 int frlast; /* Constant: last frame. */ 1504 1505 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1506 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1507 1508 replay = sav->replay; 1509 1510 if (replay->wsize == 0) 1511 goto ok; /* No need to check replay. */ 1512 1513 /* Constant. */ 1514 frlast = replay->wsize - 1; 1515 wsizeb = replay->wsize << 3; 1516 1517 /* Sequence number of 0 is invalid. */ 1518 if (seq == 0) 1519 return (1); 1520 1521 /* First time. */ 1522 if (replay->count == 0) { 1523 replay->lastseq = seq; 1524 bzero(replay->bitmap, replay->wsize); 1525 (replay->bitmap)[frlast] = 1; 1526 goto ok; 1527 } 1528 1529 if (seq > replay->lastseq) { 1530 /* seq is larger than lastseq. */ 1531 diff = seq - replay->lastseq; 1532 1533 /* New larger sequence number. */ 1534 if (diff < wsizeb) { 1535 /* In window. */ 1536 /* Set bit for this packet. */ 1537 vshiftl(replay->bitmap, diff, replay->wsize); 1538 (replay->bitmap)[frlast] |= 1; 1539 } else { 1540 /* This packet has a "way larger". */ 1541 bzero(replay->bitmap, replay->wsize); 1542 (replay->bitmap)[frlast] = 1; 1543 } 1544 replay->lastseq = seq; 1545 1546 /* Larger is good. */ 1547 } else { 1548 /* seq is equal or less than lastseq. */ 1549 diff = replay->lastseq - seq; 1550 1551 /* Over range to check, i.e. too old or wrapped. */ 1552 if (diff >= wsizeb) 1553 return (1); 1554 1555 fr = frlast - diff / 8; 1556 1557 /* This packet already seen? */ 1558 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1559 return (1); 1560 1561 /* Mark as seen. */ 1562 (replay->bitmap)[fr] |= (1 << (diff % 8)); 1563 1564 /* Out of order but good. */ 1565 } 1566 1567 ok: 1568 if (replay->count == ~0) { 1569 1570 /* Set overflow flag. */ 1571 replay->overflow++; 1572 1573 /* Don't increment, no more packets accepted. */ 1574 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 1575 return (1); 1576 1577 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1578 __func__, replay->overflow, 1579 ipsec_logsastr(sav, buf, sizeof(buf)))); 1580 } 1581 1582 replay->count++; 1583 1584 return (0); 1585 } 1586 1587 /* 1588 * Shift variable length buffer to left. 1589 * IN: bitmap: pointer to the buffer 1590 * nbit: the number of to shift. 1591 * wsize: buffer size (bytes). 1592 */ 1593 static void 1594 vshiftl(unsigned char *bitmap, int nbit, int wsize) 1595 { 1596 int s, j, i; 1597 unsigned char over; 1598 1599 for (j = 0; j < nbit; j += 8) { 1600 s = (nbit - j < 8) ? (nbit - j): 8; 1601 bitmap[0] <<= s; 1602 for (i = 1; i < wsize; i++) { 1603 over = (bitmap[i] >> (8 - s)); 1604 bitmap[i] <<= s; 1605 bitmap[i-1] |= over; 1606 } 1607 } 1608 } 1609 1610 /* Return a printable string for the address. */ 1611 char* 1612 ipsec_address(union sockaddr_union* sa, char *buf, socklen_t size) 1613 { 1614 1615 switch (sa->sa.sa_family) { 1616 #ifdef INET 1617 case AF_INET: 1618 return (inet_ntop(AF_INET, &sa->sin.sin_addr, buf, size)); 1619 #endif /* INET */ 1620 #ifdef INET6 1621 case AF_INET6: 1622 return (inet_ntop(AF_INET6, &sa->sin6.sin6_addr, buf, size)); 1623 #endif /* INET6 */ 1624 default: 1625 return ("(unknown address family)"); 1626 } 1627 } 1628 1629 char * 1630 ipsec_logsastr(struct secasvar *sav, char *buf, size_t size) 1631 { 1632 char sbuf[INET6_ADDRSTRLEN], dbuf[INET6_ADDRSTRLEN]; 1633 1634 IPSEC_ASSERT(sav->sah->saidx.src.sa.sa_family == 1635 sav->sah->saidx.dst.sa.sa_family, ("address family mismatch")); 1636 1637 snprintf(buf, size, "SA(SPI=%08lx src=%s dst=%s)", 1638 (u_long)ntohl(sav->spi), 1639 ipsec_address(&sav->sah->saidx.src, sbuf, sizeof(sbuf)), 1640 ipsec_address(&sav->sah->saidx.dst, dbuf, sizeof(dbuf))); 1641 return (buf); 1642 } 1643 1644 void 1645 ipsec_dumpmbuf(struct mbuf *m) 1646 { 1647 int totlen; 1648 int i; 1649 u_char *p; 1650 1651 totlen = 0; 1652 printf("---\n"); 1653 while (m) { 1654 p = mtod(m, u_char *); 1655 for (i = 0; i < m->m_len; i++) { 1656 printf("%02x ", p[i]); 1657 totlen++; 1658 if (totlen % 16 == 0) 1659 printf("\n"); 1660 } 1661 m = m->m_next; 1662 } 1663 if (totlen % 16 != 0) 1664 printf("\n"); 1665 printf("---\n"); 1666 } 1667 1668 static void 1669 def_policy_init(const void *unused __unused) 1670 { 1671 1672 bzero(&V_def_policy, sizeof(struct secpolicy)); 1673 V_def_policy.policy = IPSEC_POLICY_NONE; 1674 V_def_policy.refcnt = 1; 1675 } 1676 VNET_SYSINIT(def_policy_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, 1677 def_policy_init, NULL); 1678 1679 1680 /* XXX This stuff doesn't belong here... */ 1681 1682 static struct xformsw* xforms = NULL; 1683 1684 /* 1685 * Register a transform; typically at system startup. 1686 */ 1687 void 1688 xform_register(struct xformsw* xsp) 1689 { 1690 1691 xsp->xf_next = xforms; 1692 xforms = xsp; 1693 } 1694 1695 /* 1696 * Initialize transform support in an sav. 1697 */ 1698 int 1699 xform_init(struct secasvar *sav, int xftype) 1700 { 1701 struct xformsw *xsp; 1702 1703 if (sav->tdb_xform != NULL) /* Previously initialized. */ 1704 return (0); 1705 for (xsp = xforms; xsp; xsp = xsp->xf_next) 1706 if (xsp->xf_type == xftype) 1707 return ((*xsp->xf_init)(sav, xsp)); 1708 return (EINVAL); 1709 } 1710