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