1 /* $FreeBSD$ */ 2 /* $KAME: ipsec.c,v 1.103 2001/05/24 07:14:18 sakane Exp $ */ 3 4 /*- 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * IPsec controller part. 35 */ 36 37 #include "opt_inet.h" 38 #include "opt_inet6.h" 39 #include "opt_ipsec.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/malloc.h> 44 #include <sys/mbuf.h> 45 #include <sys/domain.h> 46 #include <sys/priv.h> 47 #include <sys/protosw.h> 48 #include <sys/socket.h> 49 #include <sys/socketvar.h> 50 #include <sys/errno.h> 51 #include <sys/time.h> 52 #include <sys/kernel.h> 53 #include <sys/syslog.h> 54 #include <sys/sysctl.h> 55 #include <sys/proc.h> 56 57 #include <net/if.h> 58 #include <net/if_var.h> 59 #include <net/route.h> 60 #include <net/vnet.h> 61 62 #include <netinet/in.h> 63 #include <netinet/in_systm.h> 64 #include <netinet/ip.h> 65 #include <netinet/ip_var.h> 66 #include <netinet/in_var.h> 67 #include <netinet/udp.h> 68 #include <netinet/udp_var.h> 69 #include <netinet/tcp.h> 70 #include <netinet/udp.h> 71 72 #include <netinet/ip6.h> 73 #ifdef INET6 74 #include <netinet6/ip6_var.h> 75 #endif 76 #include <netinet/in_pcb.h> 77 #ifdef INET6 78 #include <netinet/icmp6.h> 79 #endif 80 81 #include <sys/types.h> 82 #include <netipsec/ipsec.h> 83 #ifdef INET6 84 #include <netipsec/ipsec6.h> 85 #endif 86 #include <netipsec/ah_var.h> 87 #include <netipsec/esp_var.h> 88 #include <netipsec/ipcomp.h> /*XXX*/ 89 #include <netipsec/ipcomp_var.h> 90 91 #include <netipsec/key.h> 92 #include <netipsec/keydb.h> 93 #include <netipsec/key_debug.h> 94 95 #include <netipsec/xform.h> 96 97 #include <machine/in_cksum.h> 98 99 #include <opencrypto/cryptodev.h> 100 101 #ifdef IPSEC_DEBUG 102 VNET_DEFINE(int, ipsec_debug) = 1; 103 #else 104 VNET_DEFINE(int, ipsec_debug) = 0; 105 #endif 106 107 /* NB: name changed so netstat doesn't use it. */ 108 VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec4stat); 109 VNET_PCPUSTAT_SYSINIT(ipsec4stat); 110 111 #ifdef VIMAGE 112 VNET_PCPUSTAT_SYSUNINIT(ipsec4stat); 113 #endif /* VIMAGE */ 114 115 VNET_DEFINE(int, ip4_ah_offsetmask) = 0; /* maybe IP_DF? */ 116 /* DF bit on encap. 0: clear 1: set 2: copy */ 117 VNET_DEFINE(int, ip4_ipsec_dfbit) = 0; 118 VNET_DEFINE(int, ip4_esp_trans_deflev) = IPSEC_LEVEL_USE; 119 VNET_DEFINE(int, ip4_esp_net_deflev) = IPSEC_LEVEL_USE; 120 VNET_DEFINE(int, ip4_ah_trans_deflev) = IPSEC_LEVEL_USE; 121 VNET_DEFINE(int, ip4_ah_net_deflev) = IPSEC_LEVEL_USE; 122 VNET_DEFINE(struct secpolicy, ip4_def_policy); 123 /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 124 VNET_DEFINE(int, ip4_ipsec_ecn) = 0; 125 VNET_DEFINE(int, ip4_esp_randpad) = -1; 126 127 /* 128 * Crypto support requirements: 129 * 130 * 1 require hardware support 131 * -1 require software support 132 * 0 take anything 133 */ 134 VNET_DEFINE(int, crypto_support) = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE; 135 136 FEATURE(ipsec, "Internet Protocol Security (IPsec)"); 137 #ifdef IPSEC_NAT_T 138 FEATURE(ipsec_natt, "UDP Encapsulation of IPsec ESP Packets ('NAT-T')"); 139 #endif 140 141 SYSCTL_DECL(_net_inet_ipsec); 142 143 /* net.inet.ipsec */ 144 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy, 145 CTLFLAG_RW, &VNET_NAME(ip4_def_policy).policy, 0, 146 "IPsec default policy."); 147 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev, 148 CTLFLAG_RW, &VNET_NAME(ip4_esp_trans_deflev), 0, 149 "Default ESP transport mode level"); 150 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev, 151 CTLFLAG_RW, &VNET_NAME(ip4_esp_net_deflev), 0, 152 "Default ESP tunnel mode level."); 153 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev, 154 CTLFLAG_RW, &VNET_NAME(ip4_ah_trans_deflev), 0, 155 "AH transfer mode default level."); 156 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev, 157 CTLFLAG_RW, &VNET_NAME(ip4_ah_net_deflev), 0, 158 "AH tunnel mode default level."); 159 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos, 160 CTLFLAG_RW, &VNET_NAME(ah_cleartos), 0, 161 "If set clear type-of-service field when doing AH computation."); 162 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, ah_offsetmask, 163 CTLFLAG_RW, &VNET_NAME(ip4_ah_offsetmask), 0, 164 "If not set clear offset field mask when doing AH computation."); 165 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit, 166 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_dfbit), 0, 167 "Do not fragment bit on encap."); 168 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn, 169 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_ecn), 0, 170 "Explicit Congestion Notification handling."); 171 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEBUG, debug, 172 CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0, 173 "Enable IPsec debugging output when set."); 174 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, crypto_support, 175 CTLFLAG_RW, &VNET_NAME(crypto_support), 0, 176 "Crypto driver selection."); 177 SYSCTL_VNET_PCPUSTAT(_net_inet_ipsec, OID_AUTO, ipsecstats, struct ipsecstat, 178 ipsec4stat, "IPsec IPv4 statistics."); 179 180 #ifdef REGRESSION 181 /* 182 * When set to 1, IPsec will send packets with the same sequence number. 183 * This allows to verify if the other side has proper replay attacks detection. 184 */ 185 VNET_DEFINE(int, ipsec_replay) = 0; 186 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_replay, 187 CTLFLAG_RW, &VNET_NAME(ipsec_replay), 0, 188 "Emulate replay attack"); 189 /* 190 * When set 1, IPsec will send packets with corrupted HMAC. 191 * This allows to verify if the other side properly detects modified packets. 192 */ 193 VNET_DEFINE(int, ipsec_integrity) = 0; 194 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_integrity, 195 CTLFLAG_RW, &VNET_NAME(ipsec_integrity), 0, 196 "Emulate man-in-the-middle attack"); 197 #endif 198 199 #ifdef INET6 200 VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec6stat); 201 VNET_PCPUSTAT_SYSINIT(ipsec6stat); 202 203 #ifdef VIMAGE 204 VNET_PCPUSTAT_SYSUNINIT(ipsec6stat); 205 #endif /* VIMAGE */ 206 207 VNET_DEFINE(int, ip6_esp_trans_deflev) = IPSEC_LEVEL_USE; 208 VNET_DEFINE(int, ip6_esp_net_deflev) = IPSEC_LEVEL_USE; 209 VNET_DEFINE(int, ip6_ah_trans_deflev) = IPSEC_LEVEL_USE; 210 VNET_DEFINE(int, ip6_ah_net_deflev) = IPSEC_LEVEL_USE; 211 VNET_DEFINE(int, ip6_ipsec_ecn) = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */ 212 213 SYSCTL_DECL(_net_inet6_ipsec6); 214 215 /* net.inet6.ipsec6 */ 216 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy, CTLFLAG_RW, 217 &VNET_NAME(ip4_def_policy).policy, 0, 218 "IPsec default policy."); 219 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV, 220 esp_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_trans_deflev), 0, 221 "Default ESP transport mode level."); 222 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV, 223 esp_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_net_deflev), 0, 224 "Default ESP tunnel mode level."); 225 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV, 226 ah_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_trans_deflev), 0, 227 "AH transfer mode default level."); 228 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV, 229 ah_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_net_deflev), 0, 230 "AH tunnel mode default level."); 231 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_ECN, 232 ecn, CTLFLAG_RW, &VNET_NAME(ip6_ipsec_ecn), 0, 233 "Explicit Congestion Notification handling."); 234 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEBUG, debug, CTLFLAG_RW, 235 &VNET_NAME(ipsec_debug), 0, 236 "Enable IPsec debugging output when set."); 237 SYSCTL_VNET_PCPUSTAT(_net_inet6_ipsec6, IPSECCTL_STATS, ipsecstats, 238 struct ipsecstat, ipsec6stat, "IPsec IPv6 statistics."); 239 #endif /* INET6 */ 240 241 static int ipsec_setspidx_inpcb __P((struct mbuf *, struct inpcb *)); 242 static int ipsec_setspidx __P((struct mbuf *, struct secpolicyindex *, int)); 243 static void ipsec4_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 244 static int ipsec4_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 245 #ifdef INET6 246 static void ipsec6_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int)); 247 static int ipsec6_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *)); 248 #endif 249 static void ipsec_delpcbpolicy __P((struct inpcbpolicy *)); 250 static struct secpolicy *ipsec_deepcopy_policy __P((struct secpolicy *src)); 251 static void vshiftl __P((unsigned char *, int, int)); 252 253 MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy"); 254 255 /* 256 * Return a held reference to the default SP. 257 */ 258 static struct secpolicy * 259 key_allocsp_default(const char* where, int tag) 260 { 261 struct secpolicy *sp; 262 263 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 264 printf("DP key_allocsp_default from %s:%u\n", where, tag)); 265 266 sp = &V_ip4_def_policy; 267 if (sp->policy != IPSEC_POLICY_DISCARD && 268 sp->policy != IPSEC_POLICY_NONE) { 269 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n", 270 sp->policy, IPSEC_POLICY_NONE)); 271 sp->policy = IPSEC_POLICY_NONE; 272 } 273 key_addref(sp); 274 275 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 276 printf("DP key_allocsp_default returns SP:%p (%u)\n", 277 sp, sp->refcnt)); 278 return (sp); 279 } 280 #define KEY_ALLOCSP_DEFAULT() \ 281 key_allocsp_default(__FILE__, __LINE__) 282 283 /* 284 * For OUTBOUND packet having a socket. Searching SPD for packet, 285 * and return a pointer to SP. 286 * OUT: NULL: no apropreate SP found, the following value is set to error. 287 * 0 : bypass 288 * EACCES : discard packet. 289 * ENOENT : ipsec_acquire() in progress, maybe. 290 * others : error occured. 291 * others: a pointer to SP 292 * 293 * NOTE: IPv6 mapped adddress concern is implemented here. 294 */ 295 struct secpolicy * 296 ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir) 297 { 298 struct secpolicy *sp; 299 300 IPSEC_ASSERT(tdbi != NULL, ("null tdbi")); 301 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 302 ("invalid direction %u", dir)); 303 304 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir); 305 if (sp == NULL) /*XXX????*/ 306 sp = KEY_ALLOCSP_DEFAULT(); 307 IPSEC_ASSERT(sp != NULL, ("null SP")); 308 return (sp); 309 } 310 311 /* 312 * For OUTBOUND packet having a socket. Searching SPD for packet, 313 * and return a pointer to SP. 314 * OUT: NULL: no apropreate SP found, the following value is set to error. 315 * 0 : bypass 316 * EACCES : discard packet. 317 * ENOENT : ipsec_acquire() in progress, maybe. 318 * others : error occured. 319 * others: a pointer to SP 320 * 321 * NOTE: IPv6 mapped adddress concern is implemented here. 322 */ 323 static struct secpolicy * 324 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb *inp, int *error) 325 { 326 struct inpcbpolicy *pcbsp; 327 struct secpolicy *currsp = NULL; /* Policy on socket. */ 328 struct secpolicy *sp; 329 330 IPSEC_ASSERT(m != NULL, ("null mbuf")); 331 IPSEC_ASSERT(inp != NULL, ("null inpcb")); 332 IPSEC_ASSERT(error != NULL, ("null error")); 333 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 334 ("invalid direction %u", dir)); 335 336 /* Set spidx in pcb. */ 337 *error = ipsec_setspidx_inpcb(m, inp); 338 if (*error) 339 return (NULL); 340 341 pcbsp = inp->inp_sp; 342 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp")); 343 switch (dir) { 344 case IPSEC_DIR_INBOUND: 345 currsp = pcbsp->sp_in; 346 break; 347 case IPSEC_DIR_OUTBOUND: 348 currsp = pcbsp->sp_out; 349 break; 350 } 351 IPSEC_ASSERT(currsp != NULL, ("null currsp")); 352 353 if (pcbsp->priv) { /* When privilieged socket. */ 354 switch (currsp->policy) { 355 case IPSEC_POLICY_BYPASS: 356 case IPSEC_POLICY_IPSEC: 357 key_addref(currsp); 358 sp = currsp; 359 break; 360 361 case IPSEC_POLICY_ENTRUST: 362 /* Look for a policy in SPD. */ 363 sp = KEY_ALLOCSP(&currsp->spidx, dir); 364 if (sp == NULL) /* No SP found. */ 365 sp = KEY_ALLOCSP_DEFAULT(); 366 break; 367 368 default: 369 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n", 370 __func__, currsp->policy)); 371 *error = EINVAL; 372 return (NULL); 373 } 374 } else { /* Unpriv, SPD has policy. */ 375 sp = KEY_ALLOCSP(&currsp->spidx, dir); 376 if (sp == NULL) { /* No SP found. */ 377 switch (currsp->policy) { 378 case IPSEC_POLICY_BYPASS: 379 ipseclog((LOG_ERR, "%s: Illegal policy for " 380 "non-priviliged defined %d\n", 381 __func__, currsp->policy)); 382 *error = EINVAL; 383 return (NULL); 384 385 case IPSEC_POLICY_ENTRUST: 386 sp = KEY_ALLOCSP_DEFAULT(); 387 break; 388 389 case IPSEC_POLICY_IPSEC: 390 key_addref(currsp); 391 sp = currsp; 392 break; 393 394 default: 395 ipseclog((LOG_ERR, "%s: Invalid policy for " 396 "PCB %d\n", __func__, currsp->policy)); 397 *error = EINVAL; 398 return (NULL); 399 } 400 } 401 } 402 IPSEC_ASSERT(sp != NULL, 403 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy)); 404 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 405 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n", 406 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt)); 407 return (sp); 408 } 409 410 /* 411 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet, 412 * and return a pointer to SP. 413 * OUT: positive: a pointer to the entry for security policy leaf matched. 414 * NULL: no apropreate SP found, the following value is set to error. 415 * 0 : bypass 416 * EACCES : discard packet. 417 * ENOENT : ipsec_acquire() in progress, maybe. 418 * others : error occured. 419 */ 420 struct secpolicy * 421 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error) 422 { 423 struct secpolicyindex spidx; 424 struct secpolicy *sp; 425 426 IPSEC_ASSERT(m != NULL, ("null mbuf")); 427 IPSEC_ASSERT(error != NULL, ("null error")); 428 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND, 429 ("invalid direction %u", dir)); 430 431 sp = NULL; 432 if (key_havesp(dir)) { 433 /* Make an index to look for a policy. */ 434 *error = ipsec_setspidx(m, &spidx, 435 (flag & IP_FORWARDING) ? 0 : 1); 436 if (*error != 0) { 437 DPRINTF(("%s: setpidx failed, dir %u flag %u\n", 438 __func__, dir, flag)); 439 return (NULL); 440 } 441 spidx.dir = dir; 442 443 sp = KEY_ALLOCSP(&spidx, dir); 444 } 445 if (sp == NULL) /* No SP found, use system default. */ 446 sp = KEY_ALLOCSP_DEFAULT(); 447 IPSEC_ASSERT(sp != NULL, ("null SP")); 448 return (sp); 449 } 450 451 struct secpolicy * 452 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error, 453 struct inpcb *inp) 454 { 455 struct secpolicy *sp; 456 457 *error = 0; 458 if (inp == NULL) 459 sp = ipsec_getpolicybyaddr(m, dir, flag, error); 460 else 461 sp = ipsec_getpolicybysock(m, dir, inp, error); 462 if (sp == NULL) { 463 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error")); 464 IPSECSTAT_INC(ips_out_inval); 465 return (NULL); 466 } 467 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error)); 468 switch (sp->policy) { 469 case IPSEC_POLICY_ENTRUST: 470 default: 471 printf("%s: invalid policy %u\n", __func__, sp->policy); 472 /* FALLTHROUGH */ 473 case IPSEC_POLICY_DISCARD: 474 IPSECSTAT_INC(ips_out_polvio); 475 *error = -EINVAL; /* Packet is discarded by caller. */ 476 break; 477 case IPSEC_POLICY_BYPASS: 478 case IPSEC_POLICY_NONE: 479 KEY_FREESP(&sp); 480 sp = NULL; /* NB: force NULL result. */ 481 break; 482 case IPSEC_POLICY_IPSEC: 483 if (sp->req == NULL) /* Acquire a SA. */ 484 *error = key_spdacquire(sp); 485 break; 486 } 487 if (*error != 0) { 488 KEY_FREESP(&sp); 489 sp = NULL; 490 } 491 return (sp); 492 } 493 494 static int 495 ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp) 496 { 497 int error; 498 499 IPSEC_ASSERT(inp != NULL, ("null inp")); 500 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 501 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL, 502 ("null sp_in || sp_out")); 503 504 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1); 505 if (error == 0) { 506 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND; 507 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx; 508 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND; 509 } else { 510 bzero(&inp->inp_sp->sp_in->spidx, 511 sizeof (inp->inp_sp->sp_in->spidx)); 512 bzero(&inp->inp_sp->sp_out->spidx, 513 sizeof (inp->inp_sp->sp_in->spidx)); 514 } 515 return (error); 516 } 517 518 /* 519 * Configure security policy index (src/dst/proto/sport/dport) 520 * by looking at the content of mbuf. 521 * The caller is responsible for error recovery (like clearing up spidx). 522 */ 523 static int 524 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport) 525 { 526 struct ip *ip = NULL; 527 struct ip ipbuf; 528 u_int v; 529 struct mbuf *n; 530 int len; 531 int error; 532 533 IPSEC_ASSERT(m != NULL, ("null mbuf")); 534 535 /* 536 * Validate m->m_pkthdr.len. We see incorrect length if we 537 * mistakenly call this function with inconsistent mbuf chain 538 * (like 4.4BSD tcp/udp processing). XXX Should we panic here? 539 */ 540 len = 0; 541 for (n = m; n; n = n->m_next) 542 len += n->m_len; 543 if (m->m_pkthdr.len != len) { 544 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 545 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n", 546 __func__, len, m->m_pkthdr.len)); 547 return (EINVAL); 548 } 549 550 if (m->m_pkthdr.len < sizeof(struct ip)) { 551 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 552 printf("%s: pkthdr len(%d) too small (v4), ignored.\n", 553 __func__, m->m_pkthdr.len)); 554 return (EINVAL); 555 } 556 557 if (m->m_len >= sizeof(*ip)) 558 ip = mtod(m, struct ip *); 559 else { 560 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf); 561 ip = &ipbuf; 562 } 563 v = ip->ip_v; 564 switch (v) { 565 case 4: 566 error = ipsec4_setspidx_ipaddr(m, spidx); 567 if (error) 568 return (error); 569 ipsec4_get_ulp(m, spidx, needport); 570 return (0); 571 #ifdef INET6 572 case 6: 573 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 574 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 575 printf("%s: pkthdr len(%d) too small (v6), " 576 "ignored\n", __func__, m->m_pkthdr.len)); 577 return (EINVAL); 578 } 579 error = ipsec6_setspidx_ipaddr(m, spidx); 580 if (error) 581 return (error); 582 ipsec6_get_ulp(m, spidx, needport); 583 return (0); 584 #endif 585 default: 586 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 587 printf("%s: " "unknown IP version %u, ignored.\n", 588 __func__, v)); 589 return (EINVAL); 590 } 591 } 592 593 static void 594 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 595 { 596 u_int8_t nxt; 597 int off; 598 599 /* Sanity check. */ 600 IPSEC_ASSERT(m != NULL, ("null mbuf")); 601 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short")); 602 603 if (m->m_len >= sizeof (struct ip)) { 604 struct ip *ip = mtod(m, struct ip *); 605 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 606 goto done; 607 off = ip->ip_hl << 2; 608 nxt = ip->ip_p; 609 } else { 610 struct ip ih; 611 612 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih); 613 if (ih.ip_off & htons(IP_MF | IP_OFFMASK)) 614 goto done; 615 off = ih.ip_hl << 2; 616 nxt = ih.ip_p; 617 } 618 619 while (off < m->m_pkthdr.len) { 620 struct ip6_ext ip6e; 621 struct tcphdr th; 622 struct udphdr uh; 623 624 switch (nxt) { 625 case IPPROTO_TCP: 626 spidx->ul_proto = nxt; 627 if (!needport) 628 goto done_proto; 629 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 630 goto done; 631 m_copydata(m, off, sizeof (th), (caddr_t) &th); 632 spidx->src.sin.sin_port = th.th_sport; 633 spidx->dst.sin.sin_port = th.th_dport; 634 return; 635 case IPPROTO_UDP: 636 spidx->ul_proto = nxt; 637 if (!needport) 638 goto done_proto; 639 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 640 goto done; 641 m_copydata(m, off, sizeof (uh), (caddr_t) &uh); 642 spidx->src.sin.sin_port = uh.uh_sport; 643 spidx->dst.sin.sin_port = uh.uh_dport; 644 return; 645 case IPPROTO_AH: 646 if (off + sizeof(ip6e) > m->m_pkthdr.len) 647 goto done; 648 /* XXX Sigh, this works but is totally bogus. */ 649 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e); 650 off += (ip6e.ip6e_len + 2) << 2; 651 nxt = ip6e.ip6e_nxt; 652 break; 653 case IPPROTO_ICMP: 654 default: 655 /* XXX Intermediate headers??? */ 656 spidx->ul_proto = nxt; 657 goto done_proto; 658 } 659 } 660 done: 661 spidx->ul_proto = IPSEC_ULPROTO_ANY; 662 done_proto: 663 spidx->src.sin.sin_port = IPSEC_PORT_ANY; 664 spidx->dst.sin.sin_port = IPSEC_PORT_ANY; 665 } 666 667 /* Assumes that m is sane. */ 668 static int 669 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 670 { 671 static const struct sockaddr_in template = { 672 sizeof (struct sockaddr_in), 673 AF_INET, 674 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 } 675 }; 676 677 spidx->src.sin = template; 678 spidx->dst.sin = template; 679 680 if (m->m_len < sizeof (struct ip)) { 681 m_copydata(m, offsetof(struct ip, ip_src), 682 sizeof (struct in_addr), 683 (caddr_t) &spidx->src.sin.sin_addr); 684 m_copydata(m, offsetof(struct ip, ip_dst), 685 sizeof (struct in_addr), 686 (caddr_t) &spidx->dst.sin.sin_addr); 687 } else { 688 struct ip *ip = mtod(m, struct ip *); 689 spidx->src.sin.sin_addr = ip->ip_src; 690 spidx->dst.sin.sin_addr = ip->ip_dst; 691 } 692 693 spidx->prefs = sizeof(struct in_addr) << 3; 694 spidx->prefd = sizeof(struct in_addr) << 3; 695 696 return (0); 697 } 698 699 #ifdef INET6 700 static void 701 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport) 702 { 703 int off, nxt; 704 struct tcphdr th; 705 struct udphdr uh; 706 struct icmp6_hdr ih; 707 708 /* Sanity check. */ 709 if (m == NULL) 710 panic("%s: NULL pointer was passed.\n", __func__); 711 712 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 713 printf("%s:\n", __func__); kdebug_mbuf(m)); 714 715 /* Set default. */ 716 spidx->ul_proto = IPSEC_ULPROTO_ANY; 717 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY; 718 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY; 719 720 nxt = -1; 721 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 722 if (off < 0 || m->m_pkthdr.len < off) 723 return; 724 725 switch (nxt) { 726 case IPPROTO_TCP: 727 spidx->ul_proto = nxt; 728 if (!needport) 729 break; 730 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) 731 break; 732 m_copydata(m, off, sizeof(th), (caddr_t)&th); 733 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport; 734 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport; 735 break; 736 case IPPROTO_UDP: 737 spidx->ul_proto = nxt; 738 if (!needport) 739 break; 740 if (off + sizeof(struct udphdr) > m->m_pkthdr.len) 741 break; 742 m_copydata(m, off, sizeof(uh), (caddr_t)&uh); 743 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport; 744 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport; 745 break; 746 case IPPROTO_ICMPV6: 747 spidx->ul_proto = nxt; 748 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len) 749 break; 750 m_copydata(m, off, sizeof(ih), (caddr_t)&ih); 751 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = 752 htons((uint16_t)ih.icmp6_type); 753 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = 754 htons((uint16_t)ih.icmp6_code); 755 break; 756 default: 757 /* XXX Intermediate headers??? */ 758 spidx->ul_proto = nxt; 759 break; 760 } 761 } 762 763 /* Assumes that m is sane. */ 764 static int 765 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx) 766 { 767 struct ip6_hdr *ip6 = NULL; 768 struct ip6_hdr ip6buf; 769 struct sockaddr_in6 *sin6; 770 771 if (m->m_len >= sizeof(*ip6)) 772 ip6 = mtod(m, struct ip6_hdr *); 773 else { 774 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf); 775 ip6 = &ip6buf; 776 } 777 778 sin6 = (struct sockaddr_in6 *)&spidx->src; 779 bzero(sin6, sizeof(*sin6)); 780 sin6->sin6_family = AF_INET6; 781 sin6->sin6_len = sizeof(struct sockaddr_in6); 782 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src)); 783 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 784 sin6->sin6_addr.s6_addr16[1] = 0; 785 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]); 786 } 787 spidx->prefs = sizeof(struct in6_addr) << 3; 788 789 sin6 = (struct sockaddr_in6 *)&spidx->dst; 790 bzero(sin6, sizeof(*sin6)); 791 sin6->sin6_family = AF_INET6; 792 sin6->sin6_len = sizeof(struct sockaddr_in6); 793 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst)); 794 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 795 sin6->sin6_addr.s6_addr16[1] = 0; 796 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]); 797 } 798 spidx->prefd = sizeof(struct in6_addr) << 3; 799 800 return (0); 801 } 802 #endif 803 804 static void 805 ipsec_delpcbpolicy(struct inpcbpolicy *p) 806 { 807 808 free(p, M_IPSEC_INPCB); 809 } 810 811 /* Initialize policy in PCB. */ 812 int 813 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp) 814 { 815 struct inpcbpolicy *new; 816 817 /* Sanity check. */ 818 if (so == NULL || pcb_sp == NULL) 819 panic("%s: NULL pointer was passed.\n", __func__); 820 821 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy), 822 M_IPSEC_INPCB, M_NOWAIT|M_ZERO); 823 if (new == NULL) { 824 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 825 return (ENOBUFS); 826 } 827 828 new->priv = IPSEC_IS_PRIVILEGED_SO(so); 829 830 if ((new->sp_in = KEY_NEWSP()) == NULL) { 831 ipsec_delpcbpolicy(new); 832 return (ENOBUFS); 833 } 834 new->sp_in->state = IPSEC_SPSTATE_ALIVE; 835 new->sp_in->policy = IPSEC_POLICY_ENTRUST; 836 837 if ((new->sp_out = KEY_NEWSP()) == NULL) { 838 KEY_FREESP(&new->sp_in); 839 ipsec_delpcbpolicy(new); 840 return (ENOBUFS); 841 } 842 new->sp_out->state = IPSEC_SPSTATE_ALIVE; 843 new->sp_out->policy = IPSEC_POLICY_ENTRUST; 844 845 *pcb_sp = new; 846 847 return (0); 848 } 849 850 /* Copy old IPsec policy into new. */ 851 int 852 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new) 853 { 854 struct secpolicy *sp; 855 856 sp = ipsec_deepcopy_policy(old->sp_in); 857 if (sp) { 858 KEY_FREESP(&new->sp_in); 859 new->sp_in = sp; 860 } else 861 return (ENOBUFS); 862 863 sp = ipsec_deepcopy_policy(old->sp_out); 864 if (sp) { 865 KEY_FREESP(&new->sp_out); 866 new->sp_out = sp; 867 } else 868 return (ENOBUFS); 869 870 new->priv = old->priv; 871 872 return (0); 873 } 874 875 struct ipsecrequest * 876 ipsec_newisr(void) 877 { 878 struct ipsecrequest *p; 879 880 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO); 881 if (p != NULL) 882 IPSECREQUEST_LOCK_INIT(p); 883 return (p); 884 } 885 886 void 887 ipsec_delisr(struct ipsecrequest *p) 888 { 889 890 IPSECREQUEST_LOCK_DESTROY(p); 891 free(p, M_IPSEC_SR); 892 } 893 894 /* Deep-copy a policy in PCB. */ 895 static struct secpolicy * 896 ipsec_deepcopy_policy(struct secpolicy *src) 897 { 898 struct ipsecrequest *newchain = NULL; 899 struct ipsecrequest *p; 900 struct ipsecrequest **q; 901 struct ipsecrequest *r; 902 struct secpolicy *dst; 903 904 if (src == NULL) 905 return (NULL); 906 dst = KEY_NEWSP(); 907 if (dst == NULL) 908 return (NULL); 909 910 /* 911 * Deep-copy IPsec request chain. This is required since struct 912 * ipsecrequest is not reference counted. 913 */ 914 q = &newchain; 915 for (p = src->req; p; p = p->next) { 916 *q = ipsec_newisr(); 917 if (*q == NULL) 918 goto fail; 919 (*q)->saidx.proto = p->saidx.proto; 920 (*q)->saidx.mode = p->saidx.mode; 921 (*q)->level = p->level; 922 (*q)->saidx.reqid = p->saidx.reqid; 923 924 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src)); 925 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst)); 926 927 (*q)->sp = dst; 928 929 q = &((*q)->next); 930 } 931 932 dst->req = newchain; 933 dst->state = src->state; 934 dst->policy = src->policy; 935 /* Do not touch the refcnt fields. */ 936 937 return (dst); 938 939 fail: 940 for (p = newchain; p; p = r) { 941 r = p->next; 942 ipsec_delisr(p); 943 p = NULL; 944 } 945 return (NULL); 946 } 947 948 /* Set policy and IPsec request if present. */ 949 static int 950 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname, 951 caddr_t request, size_t len, struct ucred *cred) 952 { 953 struct sadb_x_policy *xpl; 954 struct secpolicy *newsp = NULL; 955 int error; 956 957 /* Sanity check. */ 958 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL) 959 return (EINVAL); 960 if (len < sizeof(*xpl)) 961 return (EINVAL); 962 xpl = (struct sadb_x_policy *)request; 963 964 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 965 printf("%s: passed policy\n", __func__); 966 kdebug_sadb_x_policy((struct sadb_ext *)xpl)); 967 968 /* Check policy type. */ 969 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */ 970 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD 971 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE) 972 return (EINVAL); 973 974 /* Check privileged socket. */ 975 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) { 976 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0); 977 if (error) 978 return (EACCES); 979 } 980 981 /* Allocating new SP entry. */ 982 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL) 983 return (error); 984 985 newsp->state = IPSEC_SPSTATE_ALIVE; 986 987 /* Clear old SP and set new SP. */ 988 KEY_FREESP(pcb_sp); 989 *pcb_sp = newsp; 990 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 991 printf("%s: new policy\n", __func__); 992 kdebug_secpolicy(newsp)); 993 994 return (0); 995 } 996 997 int 998 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request, 999 size_t len, struct ucred *cred) 1000 { 1001 struct sadb_x_policy *xpl; 1002 struct secpolicy **pcb_sp; 1003 1004 /* Sanity check. */ 1005 if (inp == NULL || request == NULL) 1006 return (EINVAL); 1007 if (len < sizeof(*xpl)) 1008 return (EINVAL); 1009 xpl = (struct sadb_x_policy *)request; 1010 1011 /* Select direction. */ 1012 switch (xpl->sadb_x_policy_dir) { 1013 case IPSEC_DIR_INBOUND: 1014 pcb_sp = &inp->inp_sp->sp_in; 1015 break; 1016 case IPSEC_DIR_OUTBOUND: 1017 pcb_sp = &inp->inp_sp->sp_out; 1018 break; 1019 default: 1020 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1021 xpl->sadb_x_policy_dir)); 1022 return (EINVAL); 1023 } 1024 1025 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred)); 1026 } 1027 1028 int 1029 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len, 1030 struct mbuf **mp) 1031 { 1032 struct sadb_x_policy *xpl; 1033 struct secpolicy *pcb_sp; 1034 1035 /* Sanity check. */ 1036 if (inp == NULL || request == NULL || mp == NULL) 1037 return (EINVAL); 1038 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp")); 1039 if (len < sizeof(*xpl)) 1040 return (EINVAL); 1041 xpl = (struct sadb_x_policy *)request; 1042 1043 /* Select direction. */ 1044 switch (xpl->sadb_x_policy_dir) { 1045 case IPSEC_DIR_INBOUND: 1046 pcb_sp = inp->inp_sp->sp_in; 1047 break; 1048 case IPSEC_DIR_OUTBOUND: 1049 pcb_sp = inp->inp_sp->sp_out; 1050 break; 1051 default: 1052 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__, 1053 xpl->sadb_x_policy_dir)); 1054 return (EINVAL); 1055 } 1056 1057 /* Sanity check. Should be an IPSEC_ASSERT. */ 1058 if (pcb_sp == NULL) 1059 return (EINVAL); 1060 1061 *mp = key_sp2msg(pcb_sp); 1062 if (!*mp) { 1063 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__)); 1064 return (ENOBUFS); 1065 } 1066 1067 (*mp)->m_type = MT_DATA; 1068 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1069 printf("%s:\n", __func__); kdebug_mbuf(*mp)); 1070 1071 return (0); 1072 } 1073 1074 /* Delete policy in PCB. */ 1075 int 1076 ipsec_delete_pcbpolicy(struct inpcb *inp) 1077 { 1078 IPSEC_ASSERT(inp != NULL, ("null inp")); 1079 1080 if (inp->inp_sp == NULL) 1081 return (0); 1082 1083 if (inp->inp_sp->sp_in != NULL) 1084 KEY_FREESP(&inp->inp_sp->sp_in); 1085 1086 if (inp->inp_sp->sp_out != NULL) 1087 KEY_FREESP(&inp->inp_sp->sp_out); 1088 1089 ipsec_delpcbpolicy(inp->inp_sp); 1090 inp->inp_sp = NULL; 1091 1092 return (0); 1093 } 1094 1095 /* 1096 * Return current level. 1097 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned. 1098 */ 1099 u_int 1100 ipsec_get_reqlevel(struct ipsecrequest *isr) 1101 { 1102 u_int level = 0; 1103 u_int esp_trans_deflev, esp_net_deflev; 1104 u_int ah_trans_deflev, ah_net_deflev; 1105 1106 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument")); 1107 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family, 1108 ("af family mismatch, src %u, dst %u", 1109 isr->sp->spidx.src.sa.sa_family, 1110 isr->sp->spidx.dst.sa.sa_family)); 1111 1112 /* XXX Note that we have ipseclog() expanded here - code sync issue. */ 1113 #define IPSEC_CHECK_DEFAULT(lev) \ 1114 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \ 1115 && (lev) != IPSEC_LEVEL_UNIQUE) \ 1116 ? (V_ipsec_debug \ 1117 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\ 1118 (lev), IPSEC_LEVEL_REQUIRE) \ 1119 : 0), \ 1120 (lev) = IPSEC_LEVEL_REQUIRE, \ 1121 (lev) \ 1122 : (lev)) 1123 1124 /* Set default level. */ 1125 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) { 1126 #ifdef INET 1127 case AF_INET: 1128 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev); 1129 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev); 1130 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev); 1131 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev); 1132 break; 1133 #endif 1134 #ifdef INET6 1135 case AF_INET6: 1136 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev); 1137 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev); 1138 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev); 1139 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev); 1140 break; 1141 #endif /* INET6 */ 1142 default: 1143 panic("%s: unknown af %u", 1144 __func__, isr->sp->spidx.src.sa.sa_family); 1145 } 1146 1147 #undef IPSEC_CHECK_DEFAULT 1148 1149 /* Set level. */ 1150 switch (isr->level) { 1151 case IPSEC_LEVEL_DEFAULT: 1152 switch (isr->saidx.proto) { 1153 case IPPROTO_ESP: 1154 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1155 level = esp_net_deflev; 1156 else 1157 level = esp_trans_deflev; 1158 break; 1159 case IPPROTO_AH: 1160 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 1161 level = ah_net_deflev; 1162 else 1163 level = ah_trans_deflev; 1164 break; 1165 case IPPROTO_IPCOMP: 1166 /* 1167 * We don't really care, as IPcomp document says that 1168 * we shouldn't compress small packets. 1169 */ 1170 level = IPSEC_LEVEL_USE; 1171 break; 1172 default: 1173 panic("%s: Illegal protocol defined %u\n", __func__, 1174 isr->saidx.proto); 1175 } 1176 break; 1177 1178 case IPSEC_LEVEL_USE: 1179 case IPSEC_LEVEL_REQUIRE: 1180 level = isr->level; 1181 break; 1182 case IPSEC_LEVEL_UNIQUE: 1183 level = IPSEC_LEVEL_REQUIRE; 1184 break; 1185 1186 default: 1187 panic("%s: Illegal IPsec level %u\n", __func__, isr->level); 1188 } 1189 1190 return (level); 1191 } 1192 1193 /* 1194 * Check security policy requirements against the actual 1195 * packet contents. Return one if the packet should be 1196 * reject as "invalid"; otherwiser return zero to have the 1197 * packet treated as "valid". 1198 * 1199 * OUT: 1200 * 0: valid 1201 * 1: invalid 1202 */ 1203 int 1204 ipsec_in_reject(struct secpolicy *sp, struct mbuf *m) 1205 { 1206 struct ipsecrequest *isr; 1207 int need_auth; 1208 1209 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1210 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1211 1212 /* Check policy. */ 1213 switch (sp->policy) { 1214 case IPSEC_POLICY_DISCARD: 1215 return (1); 1216 case IPSEC_POLICY_BYPASS: 1217 case IPSEC_POLICY_NONE: 1218 return (0); 1219 } 1220 1221 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1222 ("invalid policy %u", sp->policy)); 1223 1224 /* XXX Should compare policy against IPsec header history. */ 1225 1226 need_auth = 0; 1227 for (isr = sp->req; isr != NULL; isr = isr->next) { 1228 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE) 1229 continue; 1230 switch (isr->saidx.proto) { 1231 case IPPROTO_ESP: 1232 if ((m->m_flags & M_DECRYPTED) == 0) { 1233 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1234 printf("%s: ESP m_flags:%x\n", __func__, 1235 m->m_flags)); 1236 return (1); 1237 } 1238 1239 if (!need_auth && 1240 isr->sav != NULL && 1241 isr->sav->tdb_authalgxform != NULL && 1242 (m->m_flags & M_AUTHIPDGM) == 0) { 1243 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1244 printf("%s: ESP/AH m_flags:%x\n", __func__, 1245 m->m_flags)); 1246 return (1); 1247 } 1248 break; 1249 case IPPROTO_AH: 1250 need_auth = 1; 1251 if ((m->m_flags & M_AUTHIPHDR) == 0) { 1252 KEYDEBUG(KEYDEBUG_IPSEC_DUMP, 1253 printf("%s: AH m_flags:%x\n", __func__, 1254 m->m_flags)); 1255 return (1); 1256 } 1257 break; 1258 case IPPROTO_IPCOMP: 1259 /* 1260 * We don't really care, as IPcomp document 1261 * says that we shouldn't compress small 1262 * packets. IPComp policy should always be 1263 * treated as being in "use" level. 1264 */ 1265 break; 1266 } 1267 } 1268 return (0); /* Valid. */ 1269 } 1270 1271 static int 1272 ipsec46_in_reject(struct mbuf *m, struct inpcb *inp) 1273 { 1274 struct secpolicy *sp; 1275 int error; 1276 int result; 1277 1278 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1279 1280 /* 1281 * Get SP for this packet. 1282 * When we are called from ip_forward(), we call 1283 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1284 */ 1285 if (inp == NULL) 1286 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error); 1287 else 1288 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error); 1289 1290 if (sp != NULL) { 1291 result = ipsec_in_reject(sp, m); 1292 KEY_FREESP(&sp); 1293 } else { 1294 result = 0; /* XXX Should be panic? 1295 * -> No, there may be error. */ 1296 } 1297 return (result); 1298 } 1299 1300 /* 1301 * Check AH/ESP integrity. 1302 * This function is called from tcp_input(), udp_input(), 1303 * and {ah,esp}4_input for tunnel mode. 1304 */ 1305 int 1306 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp) 1307 { 1308 int result; 1309 1310 result = ipsec46_in_reject(m, inp); 1311 if (result) 1312 IPSECSTAT_INC(ips_in_polvio); 1313 1314 return (result); 1315 } 1316 1317 #ifdef INET6 1318 /* 1319 * Check AH/ESP integrity. 1320 * This function is called from tcp6_input(), udp6_input(), 1321 * and {ah,esp}6_input for tunnel mode. 1322 */ 1323 int 1324 ipsec6_in_reject(struct mbuf *m, struct inpcb *inp) 1325 { 1326 int result; 1327 1328 result = ipsec46_in_reject(m, inp); 1329 if (result) 1330 IPSEC6STAT_INC(ips_in_polvio); 1331 1332 return (result); 1333 } 1334 #endif 1335 1336 /* 1337 * Compute the byte size to be occupied by IPsec header. 1338 * In case it is tunnelled, it includes the size of outer IP header. 1339 * NOTE: SP passed is freed in this function. 1340 */ 1341 static size_t 1342 ipsec_hdrsiz_internal(struct secpolicy *sp) 1343 { 1344 struct ipsecrequest *isr; 1345 size_t size; 1346 1347 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1348 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp)); 1349 1350 switch (sp->policy) { 1351 case IPSEC_POLICY_DISCARD: 1352 case IPSEC_POLICY_BYPASS: 1353 case IPSEC_POLICY_NONE: 1354 return (0); 1355 } 1356 1357 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC, 1358 ("invalid policy %u", sp->policy)); 1359 1360 size = 0; 1361 for (isr = sp->req; isr != NULL; isr = isr->next) { 1362 size_t clen = 0; 1363 1364 switch (isr->saidx.proto) { 1365 case IPPROTO_ESP: 1366 clen = esp_hdrsiz(isr->sav); 1367 break; 1368 case IPPROTO_AH: 1369 clen = ah_hdrsiz(isr->sav); 1370 break; 1371 case IPPROTO_IPCOMP: 1372 clen = sizeof(struct ipcomp); 1373 break; 1374 } 1375 1376 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 1377 switch (isr->saidx.dst.sa.sa_family) { 1378 case AF_INET: 1379 clen += sizeof(struct ip); 1380 break; 1381 #ifdef INET6 1382 case AF_INET6: 1383 clen += sizeof(struct ip6_hdr); 1384 break; 1385 #endif 1386 default: 1387 ipseclog((LOG_ERR, "%s: unknown AF %d in " 1388 "IPsec tunnel SA\n", __func__, 1389 ((struct sockaddr *)&isr->saidx.dst)->sa_family)); 1390 break; 1391 } 1392 } 1393 size += clen; 1394 } 1395 1396 return (size); 1397 } 1398 1399 /* 1400 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(), 1401 * disabled ip6_ipsec_mtu() and ip6_forward(). 1402 */ 1403 size_t 1404 ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp) 1405 { 1406 struct secpolicy *sp; 1407 int error; 1408 size_t size; 1409 1410 IPSEC_ASSERT(m != NULL, ("null mbuf")); 1411 1412 /* Get SP for this packet. 1413 * When we are called from ip_forward(), we call 1414 * ipsec_getpolicybyaddr() with IP_FORWARDING flag. 1415 */ 1416 if (inp == NULL) 1417 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error); 1418 else 1419 sp = ipsec_getpolicybysock(m, dir, inp, &error); 1420 1421 if (sp != NULL) { 1422 size = ipsec_hdrsiz_internal(sp); 1423 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 1424 printf("%s: size:%lu.\n", __func__, 1425 (unsigned long)size)); 1426 1427 KEY_FREESP(&sp); 1428 } else { 1429 size = 0; /* XXX Should be panic? 1430 * -> No, we are called w/o knowing if 1431 * IPsec processing is needed. */ 1432 } 1433 return (size); 1434 } 1435 1436 /* 1437 * Check the variable replay window. 1438 * ipsec_chkreplay() performs replay check before ICV verification. 1439 * ipsec_updatereplay() updates replay bitmap. This must be called after 1440 * ICV verification (it also performs replay check, which is usually done 1441 * beforehand). 1442 * 0 (zero) is returned if packet disallowed, 1 if packet permitted. 1443 * 1444 * Based on RFC 2401. 1445 */ 1446 int 1447 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav) 1448 { 1449 const struct secreplay *replay; 1450 u_int32_t diff; 1451 int fr; 1452 u_int32_t wsizeb; /* Constant: bits of window size. */ 1453 int frlast; /* Constant: last frame. */ 1454 1455 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1456 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1457 1458 replay = sav->replay; 1459 1460 if (replay->wsize == 0) 1461 return (1); /* No need to check replay. */ 1462 1463 /* Constant. */ 1464 frlast = replay->wsize - 1; 1465 wsizeb = replay->wsize << 3; 1466 1467 /* Sequence number of 0 is invalid. */ 1468 if (seq == 0) 1469 return (0); 1470 1471 /* First time is always okay. */ 1472 if (replay->count == 0) 1473 return (1); 1474 1475 if (seq > replay->lastseq) { 1476 /* Larger sequences are okay. */ 1477 return (1); 1478 } else { 1479 /* seq is equal or less than lastseq. */ 1480 diff = replay->lastseq - seq; 1481 1482 /* Over range to check, i.e. too old or wrapped. */ 1483 if (diff >= wsizeb) 1484 return (0); 1485 1486 fr = frlast - diff / 8; 1487 1488 /* This packet already seen? */ 1489 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1490 return (0); 1491 1492 /* Out of order but good. */ 1493 return (1); 1494 } 1495 } 1496 1497 /* 1498 * Check replay counter whether to update or not. 1499 * OUT: 0: OK 1500 * 1: NG 1501 */ 1502 int 1503 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav) 1504 { 1505 struct secreplay *replay; 1506 u_int32_t diff; 1507 int fr; 1508 u_int32_t wsizeb; /* Constant: bits of window size. */ 1509 int frlast; /* Constant: last frame. */ 1510 1511 IPSEC_ASSERT(sav != NULL, ("Null SA")); 1512 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state")); 1513 1514 replay = sav->replay; 1515 1516 if (replay->wsize == 0) 1517 goto ok; /* No need to check replay. */ 1518 1519 /* Constant. */ 1520 frlast = replay->wsize - 1; 1521 wsizeb = replay->wsize << 3; 1522 1523 /* Sequence number of 0 is invalid. */ 1524 if (seq == 0) 1525 return (1); 1526 1527 /* First time. */ 1528 if (replay->count == 0) { 1529 replay->lastseq = seq; 1530 bzero(replay->bitmap, replay->wsize); 1531 (replay->bitmap)[frlast] = 1; 1532 goto ok; 1533 } 1534 1535 if (seq > replay->lastseq) { 1536 /* seq is larger than lastseq. */ 1537 diff = seq - replay->lastseq; 1538 1539 /* New larger sequence number. */ 1540 if (diff < wsizeb) { 1541 /* In window. */ 1542 /* Set bit for this packet. */ 1543 vshiftl(replay->bitmap, diff, replay->wsize); 1544 (replay->bitmap)[frlast] |= 1; 1545 } else { 1546 /* This packet has a "way larger". */ 1547 bzero(replay->bitmap, replay->wsize); 1548 (replay->bitmap)[frlast] = 1; 1549 } 1550 replay->lastseq = seq; 1551 1552 /* Larger is good. */ 1553 } else { 1554 /* seq is equal or less than lastseq. */ 1555 diff = replay->lastseq - seq; 1556 1557 /* Over range to check, i.e. too old or wrapped. */ 1558 if (diff >= wsizeb) 1559 return (1); 1560 1561 fr = frlast - diff / 8; 1562 1563 /* This packet already seen? */ 1564 if ((replay->bitmap)[fr] & (1 << (diff % 8))) 1565 return (1); 1566 1567 /* Mark as seen. */ 1568 (replay->bitmap)[fr] |= (1 << (diff % 8)); 1569 1570 /* Out of order but good. */ 1571 } 1572 1573 ok: 1574 if (replay->count == ~0) { 1575 1576 /* Set overflow flag. */ 1577 replay->overflow++; 1578 1579 /* Don't increment, no more packets accepted. */ 1580 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) 1581 return (1); 1582 1583 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n", 1584 __func__, replay->overflow, ipsec_logsastr(sav))); 1585 } 1586 1587 replay->count++; 1588 1589 return (0); 1590 } 1591 1592 /* 1593 * Shift variable length buffer to left. 1594 * IN: bitmap: pointer to the buffer 1595 * nbit: the number of to shift. 1596 * wsize: buffer size (bytes). 1597 */ 1598 static void 1599 vshiftl(unsigned char *bitmap, int nbit, int wsize) 1600 { 1601 int s, j, i; 1602 unsigned char over; 1603 1604 for (j = 0; j < nbit; j += 8) { 1605 s = (nbit - j < 8) ? (nbit - j): 8; 1606 bitmap[0] <<= s; 1607 for (i = 1; i < wsize; i++) { 1608 over = (bitmap[i] >> (8 - s)); 1609 bitmap[i] <<= s; 1610 bitmap[i-1] |= over; 1611 } 1612 } 1613 } 1614 1615 #ifdef INET 1616 /* Return a printable string for the IPv4 address. */ 1617 static char * 1618 inet_ntoa4(struct in_addr ina) 1619 { 1620 static char buf[4][4 * sizeof "123" + 4]; 1621 unsigned char *ucp = (unsigned char *) &ina; 1622 static int i = 3; 1623 1624 /* XXX-BZ Returns static buffer. */ 1625 i = (i + 1) % 4; 1626 sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff, 1627 ucp[2] & 0xff, ucp[3] & 0xff); 1628 return (buf[i]); 1629 } 1630 #endif 1631 1632 /* Return a printable string for the address. */ 1633 char * 1634 ipsec_address(union sockaddr_union* sa) 1635 { 1636 #ifdef INET6 1637 char ip6buf[INET6_ADDRSTRLEN]; 1638 #endif 1639 1640 switch (sa->sa.sa_family) { 1641 #ifdef INET 1642 case AF_INET: 1643 return (inet_ntoa4(sa->sin.sin_addr)); 1644 #endif /* INET */ 1645 #ifdef INET6 1646 case AF_INET6: 1647 return (ip6_sprintf(ip6buf, &sa->sin6.sin6_addr)); 1648 #endif /* INET6 */ 1649 default: 1650 return ("(unknown address family)"); 1651 } 1652 } 1653 1654 const char * 1655 ipsec_logsastr(struct secasvar *sav) 1656 { 1657 static char buf[256]; 1658 char *p; 1659 struct secasindex *saidx = &sav->sah->saidx; 1660 1661 IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family, 1662 ("address family mismatch")); 1663 1664 p = buf; 1665 snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi)); 1666 while (p && *p) 1667 p++; 1668 /* NB: only use ipsec_address on one address at a time. */ 1669 snprintf(p, sizeof (buf) - (p - buf), "src=%s ", 1670 ipsec_address(&saidx->src)); 1671 while (p && *p) 1672 p++; 1673 snprintf(p, sizeof (buf) - (p - buf), "dst=%s)", 1674 ipsec_address(&saidx->dst)); 1675 1676 return (buf); 1677 } 1678 1679 void 1680 ipsec_dumpmbuf(struct mbuf *m) 1681 { 1682 int totlen; 1683 int i; 1684 u_char *p; 1685 1686 totlen = 0; 1687 printf("---\n"); 1688 while (m) { 1689 p = mtod(m, u_char *); 1690 for (i = 0; i < m->m_len; i++) { 1691 printf("%02x ", p[i]); 1692 totlen++; 1693 if (totlen % 16 == 0) 1694 printf("\n"); 1695 } 1696 m = m->m_next; 1697 } 1698 if (totlen % 16 != 0) 1699 printf("\n"); 1700 printf("---\n"); 1701 } 1702 1703 static void 1704 ipsec_init(const void *unused __unused) 1705 { 1706 1707 SECPOLICY_LOCK_INIT(&V_ip4_def_policy); 1708 V_ip4_def_policy.refcnt = 1; /* NB: disallow free. */ 1709 } 1710 VNET_SYSINIT(ipsec_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, ipsec_init, 1711 NULL); 1712 1713 1714 /* XXX This stuff doesn't belong here... */ 1715 1716 static struct xformsw* xforms = NULL; 1717 1718 /* 1719 * Register a transform; typically at system startup. 1720 */ 1721 void 1722 xform_register(struct xformsw* xsp) 1723 { 1724 1725 xsp->xf_next = xforms; 1726 xforms = xsp; 1727 } 1728 1729 /* 1730 * Initialize transform support in an sav. 1731 */ 1732 int 1733 xform_init(struct secasvar *sav, int xftype) 1734 { 1735 struct xformsw *xsp; 1736 1737 if (sav->tdb_xform != NULL) /* Previously initialized. */ 1738 return (0); 1739 for (xsp = xforms; xsp; xsp = xsp->xf_next) 1740 if (xsp->xf_type == xftype) 1741 return ((*xsp->xf_init)(sav, xsp)); 1742 return (EINVAL); 1743 } 1744