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