1 /* $NetBSD: ip_state.c,v 1.5 2013/01/09 13:23:20 christos Exp $ */ 2 3 /* 4 * Copyright (C) 2012 by Darren Reed. 5 * 6 * See the IPFILTER.LICENCE file for details on licencing. 7 * 8 * Id: ip_state.c,v 1.1.1.2 2012/07/22 13:45:37 darrenr Exp 9 */ 10 #if defined(KERNEL) || defined(_KERNEL) 11 # undef KERNEL 12 # undef _KERNEL 13 # define KERNEL 1 14 # define _KERNEL 1 15 #endif 16 #include <sys/errno.h> 17 #include <sys/types.h> 18 #include <sys/param.h> 19 #include <sys/file.h> 20 #if defined(_KERNEL) && defined(__FreeBSD_version) && \ 21 (__FreeBSD_version >= 400000) && !defined(KLD_MODULE) 22 #include "opt_inet6.h" 23 #endif 24 #if !defined(_KERNEL) && !defined(__KERNEL__) 25 # include <stdio.h> 26 # include <stdlib.h> 27 # include <string.h> 28 # define _KERNEL 29 # ifdef __OpenBSD__ 30 struct file; 31 # endif 32 # include <sys/uio.h> 33 # undef _KERNEL 34 #endif 35 #if defined(_KERNEL) && (__FreeBSD_version >= 220000) 36 # include <sys/filio.h> 37 # include <sys/fcntl.h> 38 #else 39 # include <sys/ioctl.h> 40 #endif 41 #include <sys/time.h> 42 #if !defined(linux) 43 # include <sys/protosw.h> 44 #endif 45 #include <sys/socket.h> 46 #if defined(_KERNEL) 47 # include <sys/systm.h> 48 # if !defined(__SVR4) && !defined(__svr4__) 49 # include <sys/mbuf.h> 50 # endif 51 #endif 52 #if defined(__SVR4) || defined(__svr4__) 53 # include <sys/filio.h> 54 # include <sys/byteorder.h> 55 # ifdef _KERNEL 56 # include <sys/dditypes.h> 57 # endif 58 # include <sys/stream.h> 59 # include <sys/kmem.h> 60 #endif 61 62 #include <net/if.h> 63 #ifdef sun 64 # include <net/af.h> 65 #endif 66 #include <netinet/in.h> 67 #include <netinet/in_systm.h> 68 #include <netinet/ip.h> 69 #include <netinet/tcp.h> 70 #if !defined(__hpux) && !defined(linux) 71 # include <netinet/tcp_fsm.h> 72 #endif 73 #include <netinet/udp.h> 74 #include <netinet/ip_icmp.h> 75 #if !defined(_KERNEL) 76 # include "ipf.h" 77 #endif 78 #include "netinet/ip_compat.h" 79 #include "netinet/ip_fil.h" 80 #include "netinet/ip_nat.h" 81 #include "netinet/ip_frag.h" 82 #include "netinet/ip_state.h" 83 #include "netinet/ip_proxy.h" 84 #include "netinet/ip_lookup.h" 85 #include "netinet/ip_dstlist.h" 86 #include "netinet/ip_sync.h" 87 #ifdef USE_INET6 88 #include <netinet/icmp6.h> 89 #endif 90 #if FREEBSD_GE_REV(300000) 91 # include <sys/malloc.h> 92 # if defined(_KERNEL) && !defined(IPFILTER_LKM) 93 # include <sys/libkern.h> 94 # include <sys/systm.h> 95 # endif 96 #endif 97 /* END OF INCLUDES */ 98 99 100 #if !defined(lint) 101 #if defined(__NetBSD__) 102 #include <sys/cdefs.h> 103 __KERNEL_RCSID(0, "$NetBSD: ip_state.c,v 1.5 2013/01/09 13:23:20 christos Exp $"); 104 #else 105 static const char sccsid[] = "@(#)ip_state.c 1.8 6/5/96 (C) 1993-2000 Darren Reed"; 106 static const char rcsid[] = "@(#)Id: ip_state.c,v 1.1.1.2 2012/07/22 13:45:37 darrenr Exp"; 107 #endif 108 #endif 109 110 111 static ipftuneable_t ipf_state_tuneables[] = { 112 { { (void *)offsetof(ipf_state_softc_t, ipf_state_max) }, 113 "state_max", 1, 0x7fffffff, 114 stsizeof(ipf_state_softc_t, ipf_state_max), 115 0, NULL, NULL }, 116 { { (void *)offsetof(ipf_state_softc_t, ipf_state_size) }, 117 "state_size", 1, 0x7fffffff, 118 stsizeof(ipf_state_softc_t, ipf_state_size), 119 0, NULL, ipf_state_rehash }, 120 { { (void *)offsetof(ipf_state_softc_t, ipf_state_lock) }, 121 "state_lock", 0, 1, 122 stsizeof(ipf_state_softc_t, ipf_state_lock), 123 IPFT_RDONLY, NULL, NULL }, 124 { { (void *)offsetof(ipf_state_softc_t, ipf_state_maxbucket) }, 125 "state_maxbucket", 1, 0x7fffffff, 126 stsizeof(ipf_state_softc_t, ipf_state_maxbucket), 127 0, NULL, NULL }, 128 { { (void *)offsetof(ipf_state_softc_t, ipf_state_logging) }, 129 "state_logging",0, 1, 130 stsizeof(ipf_state_softc_t, ipf_state_logging), 131 0, NULL, NULL }, 132 { { (void *)offsetof(ipf_state_softc_t, ipf_state_wm_high) }, 133 "state_wm_high",2, 100, 134 stsizeof(ipf_state_softc_t, ipf_state_wm_high), 135 0, NULL, NULL }, 136 { { (void *)offsetof(ipf_state_softc_t, ipf_state_wm_low) }, 137 "state_wm_low", 1, 99, 138 stsizeof(ipf_state_softc_t, ipf_state_wm_low), 139 0, NULL, NULL }, 140 { { (void *)offsetof(ipf_state_softc_t, ipf_state_wm_freq) }, 141 "state_wm_freq",2, 999999, 142 stsizeof(ipf_state_softc_t, ipf_state_wm_freq), 143 0, NULL, NULL }, 144 { { NULL }, 145 NULL, 0, 0, 146 0, 147 0, NULL, NULL } 148 }; 149 150 #define SINCL(x) ATOMIC_INCL(softs->x) 151 #define SBUMP(x) (softs->x)++ 152 #define SBUMPD(x, y) do { (softs->x.y)++; DT(y); } while (0) 153 #define SBUMPDX(x, y, z)do { (softs->x.y)++; DT(z); } while (0) 154 155 #ifdef USE_INET6 156 static ipstate_t *ipf_checkicmp6matchingstate(fr_info_t *); 157 #endif 158 static int ipf_allowstateicmp(fr_info_t *, ipstate_t *, i6addr_t *); 159 static ipstate_t *ipf_matchsrcdst(fr_info_t *, ipstate_t *, i6addr_t *, 160 i6addr_t *, tcphdr_t *, u_32_t); 161 static ipstate_t *ipf_checkicmpmatchingstate(fr_info_t *); 162 static int ipf_state_flush_entry(ipf_main_softc_t *, void *); 163 static ips_stat_t *ipf_state_stats(ipf_main_softc_t *); 164 static int ipf_state_del(ipf_main_softc_t *, ipstate_t *, int); 165 static int ipf_state_remove(ipf_main_softc_t *, void *); 166 static int ipf_state_match(ipstate_t *is1, ipstate_t *is2); 167 static int ipf_state_matchaddresses(ipstate_t *is1, ipstate_t *is2); 168 static int ipf_state_matchipv4addrs(ipstate_t *is1, ipstate_t *is2); 169 static int ipf_state_matchipv6addrs(ipstate_t *is1, ipstate_t *is2); 170 static int ipf_state_matchisps(ipstate_t *is1, ipstate_t *is2); 171 static int ipf_state_matchports(udpinfo_t *is1, udpinfo_t *is2); 172 static int ipf_state_matcharray(ipstate_t *, int *, u_long); 173 static void ipf_ipsmove(ipf_state_softc_t *, ipstate_t *, u_int); 174 static int ipf_state_tcp(ipf_main_softc_t *, ipf_state_softc_t *, 175 fr_info_t *, tcphdr_t *, ipstate_t *); 176 static int ipf_tcpoptions(ipf_state_softc_t *, fr_info_t *, 177 tcphdr_t *, tcpdata_t *); 178 static ipstate_t *ipf_state_clone(fr_info_t *, tcphdr_t *, ipstate_t *); 179 static void ipf_fixinisn(fr_info_t *, ipstate_t *); 180 static void ipf_fixoutisn(fr_info_t *, ipstate_t *); 181 static void ipf_checknewisn(fr_info_t *, ipstate_t *); 182 static int ipf_state_iter(ipf_main_softc_t *, ipftoken_t *, 183 ipfgeniter_t *, ipfobj_t *); 184 static int ipf_state_gettable(ipf_main_softc_t *, ipf_state_softc_t *, char *); 185 static int ipf_state_tcpinwindow(struct fr_info *, struct tcpdata *, 186 struct tcpdata *, tcphdr_t *, int); 187 188 static int ipf_state_getent(ipf_main_softc_t *, ipf_state_softc_t *, void *); 189 static int ipf_state_putent(ipf_main_softc_t *, ipf_state_softc_t *, void *); 190 191 #define ONE_DAY IPF_TTLVAL(1 * 86400) /* 1 day */ 192 #define FIVE_DAYS (5 * ONE_DAY) 193 #define DOUBLE_HASH(x) (((x) + softs->ipf_state_seed[(x) % \ 194 softs->ipf_state_size]) % softs->ipf_state_size) 195 196 197 /* ------------------------------------------------------------------------ */ 198 /* Function: ipf_state_main_load */ 199 /* Returns: int - 0 == success, -1 == failure */ 200 /* Parameters: Nil */ 201 /* */ 202 /* A null-op function that exists as a placeholder so that the flow in */ 203 /* other functions is obvious. */ 204 /* ------------------------------------------------------------------------ */ 205 int 206 ipf_state_main_load(void) 207 { 208 return 0; 209 } 210 211 212 /* ------------------------------------------------------------------------ */ 213 /* Function: ipf_state_main_unload */ 214 /* Returns: int - 0 == success, -1 == failure */ 215 /* Parameters: Nil */ 216 /* */ 217 /* A null-op function that exists as a placeholder so that the flow in */ 218 /* other functions is obvious. */ 219 /* ------------------------------------------------------------------------ */ 220 int 221 ipf_state_main_unload(void) 222 { 223 return 0; 224 } 225 226 227 /* ------------------------------------------------------------------------ */ 228 /* Function: ipf_state_soft_create */ 229 /* Returns: void * - NULL = failure, else pointer to soft context */ 230 /* Parameters: softc(I) - pointer to soft context main structure */ 231 /* */ 232 /* Create a new state soft context structure and populate it with the list */ 233 /* of tunables and other default settings. */ 234 /* ------------------------------------------------------------------------ */ 235 void * 236 ipf_state_soft_create(ipf_main_softc_t *softc) 237 { 238 ipf_state_softc_t *softs; 239 240 KMALLOC(softs, ipf_state_softc_t *); 241 if (softs == NULL) 242 return NULL; 243 244 bzero((char *)softs, sizeof(*softs)); 245 246 softs->ipf_state_tune = ipf_tune_array_copy(softs, 247 sizeof(ipf_state_tuneables), 248 ipf_state_tuneables); 249 if (softs->ipf_state_tune == NULL) { 250 ipf_state_soft_destroy(softc, softs); 251 return NULL; 252 } 253 if (ipf_tune_array_link(softc, softs->ipf_state_tune) == -1) { 254 ipf_state_soft_destroy(softc, softs); 255 return NULL; 256 } 257 258 #ifdef IPFILTER_LOG 259 softs->ipf_state_logging = 1; 260 #else 261 softs->ipf_state_logging = 0; 262 #endif 263 softs->ipf_state_size = IPSTATE_SIZE, 264 softs->ipf_state_maxbucket = 0; 265 softs->ipf_state_wm_freq = IPF_TTLVAL(10); 266 softs->ipf_state_max = IPSTATE_MAX; 267 softs->ipf_state_wm_last = 0; 268 softs->ipf_state_wm_high = 99; 269 softs->ipf_state_wm_low = 90; 270 softs->ipf_state_inited = 0; 271 softs->ipf_state_lock = 0; 272 softs->ipf_state_doflush = 0; 273 274 return softs; 275 } 276 277 278 /* ------------------------------------------------------------------------ */ 279 /* Function: ipf_state_soft_destroy */ 280 /* Returns: Nil */ 281 /* Parameters: softc(I) - pointer to soft context main structure */ 282 /* arg(I) - pointer to local context to use */ 283 /* */ 284 /* Undo only what we did in soft create: unlink and free the tunables and */ 285 /* free the soft context structure itself. */ 286 /* ------------------------------------------------------------------------ */ 287 void 288 ipf_state_soft_destroy(ipf_main_softc_t *softc, void *arg) 289 { 290 ipf_state_softc_t *softs = arg; 291 292 if (softs->ipf_state_tune != NULL) { 293 ipf_tune_array_unlink(softc, softs->ipf_state_tune); 294 KFREES(softs->ipf_state_tune, sizeof(ipf_state_tuneables)); 295 softs->ipf_state_tune = NULL; 296 } 297 298 KFREE(softs); 299 } 300 301 302 /* ------------------------------------------------------------------------ */ 303 /* Function: ipf_state_soft_init */ 304 /* Returns: int - 0 == success, -1 == failure */ 305 /* Parameters: softc(I) - pointer to soft context main structure */ 306 /* arg(I) - pointer to local context to use */ 307 /* */ 308 /* Initialise the state soft context structure so it is ready for use. */ 309 /* This involves: */ 310 /* - allocating a hash table and zero'ing it out */ 311 /* - building a secondary table of seeds for double hashing to make it more */ 312 /* difficult to attempt to attack the hash table itself (for DoS) */ 313 /* - initialise all of the timeout queues, including a table for TCP, some */ 314 /* pairs of query/response for UDP and other IP protocols (typically the */ 315 /* reply queue has a shorter timeout than the query) */ 316 /* ------------------------------------------------------------------------ */ 317 int 318 ipf_state_soft_init(ipf_main_softc_t *softc, void *arg) 319 { 320 ipf_state_softc_t *softs = arg; 321 int i; 322 323 KMALLOCS(softs->ipf_state_table, 324 ipstate_t **, softs->ipf_state_size * sizeof(ipstate_t *)); 325 if (softs->ipf_state_table == NULL) 326 return -1; 327 328 bzero((char *)softs->ipf_state_table, 329 softs->ipf_state_size * sizeof(ipstate_t *)); 330 331 KMALLOCS(softs->ipf_state_seed, u_long *, 332 softs->ipf_state_size * sizeof(*softs->ipf_state_seed)); 333 if (softs->ipf_state_seed == NULL) 334 return -2; 335 336 for (i = 0; i < softs->ipf_state_size; i++) { 337 /* 338 * XXX - ipf_state_seed[X] should be a random number of sorts. 339 */ 340 #if !defined(NEED_LOCAL_RAND) && defined(_KERNEL) 341 softs->ipf_state_seed[i] = cprng_fast32(); 342 #else 343 softs->ipf_state_seed[i] = ((u_long)softs->ipf_state_seed + i) * 344 softs->ipf_state_size; 345 softs->ipf_state_seed[i] ^= 0xa5a55a5a; 346 softs->ipf_state_seed[i] *= (u_long)softs->ipf_state_seed; 347 softs->ipf_state_seed[i] ^= 0x5a5aa5a5; 348 softs->ipf_state_seed[i] *= softs->ipf_state_max; 349 #endif 350 } 351 352 KMALLOCS(softs->ipf_state_stats.iss_bucketlen, u_int *, 353 softs->ipf_state_size * sizeof(u_int)); 354 if (softs->ipf_state_stats.iss_bucketlen == NULL) 355 return -3; 356 357 bzero((char *)softs->ipf_state_stats.iss_bucketlen, 358 softs->ipf_state_size * sizeof(u_int)); 359 360 if (softs->ipf_state_maxbucket == 0) { 361 for (i = softs->ipf_state_size; i > 0; i >>= 1) 362 softs->ipf_state_maxbucket++; 363 softs->ipf_state_maxbucket *= 2; 364 } 365 366 ipf_sttab_init(softc, softs->ipf_state_tcptq); 367 softs->ipf_state_stats.iss_tcptab = softs->ipf_state_tcptq; 368 softs->ipf_state_tcptq[IPF_TCP_NSTATES - 1].ifq_next = 369 &softs->ipf_state_udptq; 370 371 IPFTQ_INIT(&softs->ipf_state_udptq, softc->ipf_udptimeout, 372 "ipftq udp tab"); 373 softs->ipf_state_udptq.ifq_next = &softs->ipf_state_udpacktq; 374 375 IPFTQ_INIT(&softs->ipf_state_udpacktq, softc->ipf_udpacktimeout, 376 "ipftq udpack tab"); 377 softs->ipf_state_udpacktq.ifq_next = &softs->ipf_state_icmptq; 378 379 IPFTQ_INIT(&softs->ipf_state_icmptq, softc->ipf_icmptimeout, 380 "ipftq icmp tab"); 381 softs->ipf_state_icmptq.ifq_next = &softs->ipf_state_icmpacktq; 382 383 IPFTQ_INIT(&softs->ipf_state_icmpacktq, softc->ipf_icmpacktimeout, 384 "ipftq icmpack tab"); 385 softs->ipf_state_icmpacktq.ifq_next = &softs->ipf_state_iptq; 386 387 IPFTQ_INIT(&softs->ipf_state_iptq, softc->ipf_iptimeout, 388 "ipftq iptimeout tab"); 389 softs->ipf_state_iptq.ifq_next = &softs->ipf_state_pending; 390 391 IPFTQ_INIT(&softs->ipf_state_pending, IPF_HZ_DIVIDE, "ipftq pending"); 392 softs->ipf_state_pending.ifq_next = &softs->ipf_state_deletetq; 393 394 IPFTQ_INIT(&softs->ipf_state_deletetq, 1, "ipftq delete"); 395 softs->ipf_state_deletetq.ifq_next = NULL; 396 397 MUTEX_INIT(&softs->ipf_stinsert, "ipf state insert mutex"); 398 399 400 softs->ipf_state_wm_last = softc->ipf_ticks; 401 softs->ipf_state_inited = 1; 402 403 return 0; 404 } 405 406 407 /* ------------------------------------------------------------------------ */ 408 /* Function: ipf_state_soft_fini */ 409 /* Returns: int - 0 = success, -1 = failure */ 410 /* Parameters: softc(I) - pointer to soft context main structure */ 411 /* arg(I) - pointer to local context to use */ 412 /* */ 413 /* Release and destroy any resources acquired or initialised so that */ 414 /* IPFilter can be unloaded or re-initialised. */ 415 /* ------------------------------------------------------------------------ */ 416 int 417 ipf_state_soft_fini(ipf_main_softc_t *softc, void *arg) 418 { 419 ipf_state_softc_t *softs = arg; 420 ipftq_t *ifq, *ifqnext; 421 ipstate_t *is; 422 423 while ((is = softs->ipf_state_list) != NULL) 424 ipf_state_del(softc, is, ISL_UNLOAD); 425 426 /* 427 * Proxy timeout queues are not cleaned here because although they 428 * exist on the state list, appr_unload is called after 429 * ipf_state_unload and the proxies actually are responsible for them 430 * being created. Should the proxy timeouts have their own list? 431 * There's no real justification as this is the only complication. 432 */ 433 for (ifq = softs->ipf_state_usertq; ifq != NULL; ifq = ifqnext) { 434 ifqnext = ifq->ifq_next; 435 436 if (ipf_deletetimeoutqueue(ifq) == 0) 437 ipf_freetimeoutqueue(softc, ifq); 438 } 439 440 softs->ipf_state_stats.iss_inuse = 0; 441 softs->ipf_state_stats.iss_active = 0; 442 443 if (softs->ipf_state_inited == 1) { 444 softs->ipf_state_inited = 0; 445 ipf_sttab_destroy(softs->ipf_state_tcptq); 446 MUTEX_DESTROY(&softs->ipf_state_udptq.ifq_lock); 447 MUTEX_DESTROY(&softs->ipf_state_icmptq.ifq_lock); 448 MUTEX_DESTROY(&softs->ipf_state_udpacktq.ifq_lock); 449 MUTEX_DESTROY(&softs->ipf_state_icmpacktq.ifq_lock); 450 MUTEX_DESTROY(&softs->ipf_state_iptq.ifq_lock); 451 MUTEX_DESTROY(&softs->ipf_state_deletetq.ifq_lock); 452 MUTEX_DESTROY(&softs->ipf_state_pending.ifq_lock); 453 MUTEX_DESTROY(&softs->ipf_stinsert); 454 } 455 456 if (softs->ipf_state_table != NULL) { 457 KFREES(softs->ipf_state_table, 458 softs->ipf_state_size * sizeof(*softs->ipf_state_table)); 459 softs->ipf_state_table = NULL; 460 } 461 462 if (softs->ipf_state_seed != NULL) { 463 KFREES(softs->ipf_state_seed, 464 softs->ipf_state_size * sizeof(*softs->ipf_state_seed)); 465 softs->ipf_state_seed = NULL; 466 } 467 468 if (softs->ipf_state_stats.iss_bucketlen != NULL) { 469 KFREES(softs->ipf_state_stats.iss_bucketlen, 470 softs->ipf_state_size * sizeof(u_int)); 471 softs->ipf_state_stats.iss_bucketlen = NULL; 472 } 473 474 return 0; 475 } 476 477 478 /* ------------------------------------------------------------------------ */ 479 /* Function: ipf_state_set_lock */ 480 /* Returns: Nil */ 481 /* Parameters: arg(I) - pointer to local context to use */ 482 /* tmp(I) - new value for lock */ 483 /* */ 484 /* Stub function that allows for external manipulation of ipf_state_lock */ 485 /* ------------------------------------------------------------------------ */ 486 void 487 ipf_state_setlock(void *arg, int tmp) 488 { 489 ipf_state_softc_t *softs = arg; 490 491 softs->ipf_state_lock = tmp; 492 } 493 494 495 /* ------------------------------------------------------------------------ */ 496 /* Function: ipf_state_stats */ 497 /* Returns: ips_state_t* - pointer to state stats structure */ 498 /* Parameters: softc(I) - pointer to soft context main structure */ 499 /* */ 500 /* Put all the current numbers and pointers into a single struct and return */ 501 /* a pointer to it. */ 502 /* ------------------------------------------------------------------------ */ 503 static ips_stat_t * 504 ipf_state_stats(ipf_main_softc_t *softc) 505 { 506 ipf_state_softc_t *softs = softc->ipf_state_soft; 507 ips_stat_t *issp = &softs->ipf_state_stats; 508 509 issp->iss_state_size = softs->ipf_state_size; 510 issp->iss_state_max = softs->ipf_state_max; 511 issp->iss_table = softs->ipf_state_table; 512 issp->iss_list = softs->ipf_state_list; 513 issp->iss_ticks = softc->ipf_ticks; 514 515 #ifdef IPFILTER_LOGGING 516 issp->iss_log_ok = ipf_log_logok(softc, IPF_LOGSTATE); 517 issp->iss_log_fail = ipf_log_failures(softc, IPF_LOGSTATE); 518 #else 519 issp->iss_log_ok = 0; 520 issp->iss_log_fail = 0; 521 #endif 522 return issp; 523 } 524 525 /* ------------------------------------------------------------------------ */ 526 /* Function: ipf_state_remove */ 527 /* Returns: int - 0 == success, != 0 == failure */ 528 /* Parameters: softc(I) - pointer to soft context main structure */ 529 /* data(I) - pointer to state structure to delete from table */ 530 /* */ 531 /* Search for a state structure that matches the one passed, according to */ 532 /* the IP addresses and other protocol specific information. */ 533 /* ------------------------------------------------------------------------ */ 534 static int 535 ipf_state_remove(ipf_main_softc_t *softc, void *data) 536 { 537 ipf_state_softc_t *softs = softc->ipf_state_soft; 538 ipstate_t *sp, st; 539 int error; 540 541 sp = &st; 542 error = ipf_inobj(softc, data, NULL, &st, IPFOBJ_IPSTATE); 543 if (error) 544 return EFAULT; 545 546 WRITE_ENTER(&softc->ipf_state); 547 for (sp = softs->ipf_state_list; sp; sp = sp->is_next) 548 if ((sp->is_p == st.is_p) && (sp->is_v == st.is_v) && 549 !bcmp((void *)&sp->is_src, (void *)&st.is_src, 550 sizeof(st.is_src)) && 551 !bcmp((void *)&sp->is_dst, (void *)&st.is_src, 552 sizeof(st.is_dst)) && 553 !bcmp((void *)&sp->is_ps, (void *)&st.is_ps, 554 sizeof(st.is_ps))) { 555 ipf_state_del(softc, sp, ISL_REMOVE); 556 RWLOCK_EXIT(&softc->ipf_state); 557 return 0; 558 } 559 RWLOCK_EXIT(&softc->ipf_state); 560 561 IPFERROR(100001); 562 return ESRCH; 563 } 564 565 566 /* ------------------------------------------------------------------------ */ 567 /* Function: ipf_state_ioctl */ 568 /* Returns: int - 0 == success, != 0 == failure */ 569 /* Parameters: softc(I) - pointer to soft context main structure */ 570 /* data(I) - pointer to ioctl data */ 571 /* cmd(I) - ioctl command integer */ 572 /* mode(I) - file mode bits used with open */ 573 /* uid(I) - uid of process making the ioctl call */ 574 /* ctx(I) - pointer specific to context of the call */ 575 /* */ 576 /* Processes an ioctl call made to operate on the IP Filter state device. */ 577 /* ------------------------------------------------------------------------ */ 578 int 579 ipf_state_ioctl(ipf_main_softc_t *softc, void *data, ioctlcmd_t cmd, int mode, 580 int uid, void *ctx) 581 { 582 ipf_state_softc_t *softs = softc->ipf_state_soft; 583 int arg, ret, error = 0; 584 SPL_INT(s); 585 586 switch (cmd) 587 { 588 /* 589 * Delete an entry from the state table. 590 */ 591 case SIOCDELST : 592 error = ipf_state_remove(softc, data); 593 break; 594 595 /* 596 * Flush the state table 597 */ 598 case SIOCIPFFL : 599 error = BCOPYIN(data, &arg, sizeof(arg)); 600 if (error != 0) { 601 IPFERROR(100002); 602 error = EFAULT; 603 604 } else { 605 WRITE_ENTER(&softc->ipf_state); 606 ret = ipf_state_flush(softc, arg, 4); 607 RWLOCK_EXIT(&softc->ipf_state); 608 609 error = BCOPYOUT(&ret, data, sizeof(ret)); 610 if (error != 0) { 611 IPFERROR(100003); 612 error = EFAULT; 613 } 614 } 615 break; 616 617 #ifdef USE_INET6 618 case SIOCIPFL6 : 619 error = BCOPYIN(data, &arg, sizeof(arg)); 620 if (error != 0) { 621 IPFERROR(100004); 622 error = EFAULT; 623 624 } else { 625 WRITE_ENTER(&softc->ipf_state); 626 ret = ipf_state_flush(softc, arg, 6); 627 RWLOCK_EXIT(&softc->ipf_state); 628 629 error = BCOPYOUT(&ret, data, sizeof(ret)); 630 if (error != 0) { 631 IPFERROR(100005); 632 error = EFAULT; 633 } 634 } 635 break; 636 #endif 637 638 case SIOCMATCHFLUSH : 639 WRITE_ENTER(&softc->ipf_state); 640 error = ipf_state_matchflush(softc, data); 641 RWLOCK_EXIT(&softc->ipf_state); 642 break; 643 644 #ifdef IPFILTER_LOG 645 /* 646 * Flush the state log. 647 */ 648 case SIOCIPFFB : 649 if (!(mode & FWRITE)) { 650 IPFERROR(100008); 651 error = EPERM; 652 } else { 653 int tmp; 654 655 tmp = ipf_log_clear(softc, IPL_LOGSTATE); 656 error = BCOPYOUT(&tmp, data, sizeof(tmp)); 657 if (error != 0) { 658 IPFERROR(100009); 659 error = EFAULT; 660 } 661 } 662 break; 663 664 /* 665 * Turn logging of state information on/off. 666 */ 667 case SIOCSETLG : 668 if (!(mode & FWRITE)) { 669 IPFERROR(100010); 670 error = EPERM; 671 } else { 672 error = BCOPYIN(data, &softs->ipf_state_logging, 673 sizeof(softs->ipf_state_logging)); 674 if (error != 0) { 675 IPFERROR(100011); 676 error = EFAULT; 677 } 678 } 679 break; 680 681 /* 682 * Return the current state of logging. 683 */ 684 case SIOCGETLG : 685 error = BCOPYOUT(&softs->ipf_state_logging, data, 686 sizeof(softs->ipf_state_logging)); 687 if (error != 0) { 688 IPFERROR(100012); 689 error = EFAULT; 690 } 691 break; 692 693 /* 694 * Return the number of bytes currently waiting to be read. 695 */ 696 case FIONREAD : 697 arg = ipf_log_bytesused(softc, IPL_LOGSTATE); 698 error = BCOPYOUT(&arg, data, sizeof(arg)); 699 if (error != 0) { 700 IPFERROR(100013); 701 error = EFAULT; 702 } 703 break; 704 #endif 705 706 /* 707 * Get the current state statistics. 708 */ 709 case SIOCGETFS : 710 error = ipf_outobj(softc, data, ipf_state_stats(softc), 711 IPFOBJ_STATESTAT); 712 break; 713 714 /* 715 * Lock/Unlock the state table. (Locking prevents any changes, which 716 * means no packets match). 717 */ 718 case SIOCSTLCK : 719 if (!(mode & FWRITE)) { 720 IPFERROR(100014); 721 error = EPERM; 722 } else { 723 error = ipf_lock(data, &softs->ipf_state_lock); 724 } 725 break; 726 727 /* 728 * Add an entry to the current state table. 729 */ 730 case SIOCSTPUT : 731 if (!softs->ipf_state_lock || !(mode &FWRITE)) { 732 IPFERROR(100015); 733 error = EACCES; 734 break; 735 } 736 error = ipf_state_putent(softc, softs, data); 737 break; 738 739 /* 740 * Get a state table entry. 741 */ 742 case SIOCSTGET : 743 if (!softs->ipf_state_lock) { 744 IPFERROR(100016); 745 error = EACCES; 746 break; 747 } 748 error = ipf_state_getent(softc, softs, data); 749 break; 750 751 /* 752 * Return a copy of the hash table bucket lengths 753 */ 754 case SIOCSTAT1 : 755 error = BCOPYOUT(softs->ipf_state_stats.iss_bucketlen, data, 756 softs->ipf_state_size * sizeof(u_int)); 757 if (error != 0) { 758 IPFERROR(100017); 759 error = EFAULT; 760 } 761 break; 762 763 case SIOCGENITER : 764 { 765 ipftoken_t *token; 766 ipfgeniter_t iter; 767 ipfobj_t obj; 768 769 error = ipf_inobj(softc, data, &obj, &iter, IPFOBJ_GENITER); 770 if (error != 0) 771 break; 772 773 SPL_SCHED(s); 774 token = ipf_token_find(softc, IPFGENITER_STATE, uid, ctx); 775 if (token != NULL) { 776 error = ipf_state_iter(softc, token, &iter, &obj); 777 WRITE_ENTER(&softc->ipf_tokens); 778 ipf_token_deref(softc, token); 779 RWLOCK_EXIT(&softc->ipf_tokens); 780 } else { 781 IPFERROR(100018); 782 error = ESRCH; 783 } 784 SPL_X(s); 785 break; 786 } 787 788 case SIOCGTABL : 789 error = ipf_state_gettable(softc, softs, data); 790 break; 791 792 case SIOCIPFDELTOK : 793 error = BCOPYIN(data, &arg, sizeof(arg)); 794 if (error != 0) { 795 IPFERROR(100019); 796 error = EFAULT; 797 } else { 798 SPL_SCHED(s); 799 error = ipf_token_del(softc, arg, uid, ctx); 800 SPL_X(s); 801 } 802 break; 803 804 case SIOCGTQTAB : 805 error = ipf_outobj(softc, data, softs->ipf_state_tcptq, 806 IPFOBJ_STATETQTAB); 807 break; 808 809 default : 810 IPFERROR(100020); 811 error = EINVAL; 812 break; 813 } 814 return error; 815 } 816 817 818 /* ------------------------------------------------------------------------ */ 819 /* Function: ipf_state_getent */ 820 /* Returns: int - 0 == success, != 0 == failure */ 821 /* Parameters: softc(I) - pointer to soft context main structure */ 822 /* softs(I) - pointer to state context structure */ 823 /* data(I) - pointer to state structure to retrieve from table*/ 824 /* */ 825 /* Copy out state information from the kernel to a user space process. If */ 826 /* there is a filter rule associated with the state entry, copy that out */ 827 /* as well. The entry to copy out is taken from the value of "ips_next" in */ 828 /* the struct passed in and if not null and not found in the list of current*/ 829 /* state entries, the retrieval fails. */ 830 /* ------------------------------------------------------------------------ */ 831 static int 832 ipf_state_getent(ipf_main_softc_t *softc, ipf_state_softc_t *softs, void *data) 833 { 834 ipstate_t *is, *isn; 835 ipstate_save_t ips; 836 int error; 837 838 error = ipf_inobj(softc, data, NULL, &ips, IPFOBJ_STATESAVE); 839 if (error) 840 return EFAULT; 841 842 READ_ENTER(&softc->ipf_state); 843 isn = ips.ips_next; 844 if (isn == NULL) { 845 isn = softs->ipf_state_list; 846 if (isn == NULL) { 847 if (ips.ips_next == NULL) { 848 RWLOCK_EXIT(&softc->ipf_state); 849 IPFERROR(100021); 850 return ENOENT; 851 } 852 return 0; 853 } 854 } else { 855 /* 856 * Make sure the pointer we're copying from exists in the 857 * current list of entries. Security precaution to prevent 858 * copying of random kernel data. 859 */ 860 for (is = softs->ipf_state_list; is; is = is->is_next) 861 if (is == isn) 862 break; 863 if (!is) { 864 RWLOCK_EXIT(&softc->ipf_state); 865 IPFERROR(100022); 866 return ESRCH; 867 } 868 } 869 ips.ips_next = isn->is_next; 870 bcopy((char *)isn, (char *)&ips.ips_is, sizeof(ips.ips_is)); 871 ips.ips_rule = isn->is_rule; 872 if (isn->is_rule != NULL) 873 bcopy((char *)isn->is_rule, (char *)&ips.ips_fr, 874 sizeof(ips.ips_fr)); 875 RWLOCK_EXIT(&softc->ipf_state); 876 error = ipf_outobj(softc, data, &ips, IPFOBJ_STATESAVE); 877 return error; 878 } 879 880 881 /* ------------------------------------------------------------------------ */ 882 /* Function: ipf_state_putent */ 883 /* Returns: int - 0 == success, != 0 == failure */ 884 /* Parameters: softc(I) - pointer to soft context main structure */ 885 /* softs(I) - pointer to state context structure */ 886 /* data(I) - pointer to state information struct */ 887 /* */ 888 /* This function implements the SIOCSTPUT ioctl: insert a state entry into */ 889 /* the state table. If the state info. includes a pointer to a filter rule */ 890 /* then also add in an orphaned rule (will not show up in any "ipfstat -io" */ 891 /* output. */ 892 /* ------------------------------------------------------------------------ */ 893 int 894 ipf_state_putent(ipf_main_softc_t *softc, ipf_state_softc_t *softs, void *data) 895 { 896 ipstate_t *is, *isn; 897 ipstate_save_t ips; 898 int error, out, i; 899 frentry_t *fr; 900 char *name; 901 902 error = ipf_inobj(softc, data, NULL, &ips, IPFOBJ_STATESAVE); 903 if (error != 0) 904 return error; 905 906 KMALLOC(isn, ipstate_t *); 907 if (isn == NULL) { 908 IPFERROR(100023); 909 return ENOMEM; 910 } 911 912 bcopy((char *)&ips.ips_is, (char *)isn, sizeof(*isn)); 913 bzero((char *)isn, offsetof(struct ipstate, is_pkts)); 914 isn->is_sti.tqe_pnext = NULL; 915 isn->is_sti.tqe_next = NULL; 916 isn->is_sti.tqe_ifq = NULL; 917 isn->is_sti.tqe_parent = isn; 918 isn->is_ifp[0] = NULL; 919 isn->is_ifp[1] = NULL; 920 isn->is_ifp[2] = NULL; 921 isn->is_ifp[3] = NULL; 922 isn->is_sync = NULL; 923 fr = ips.ips_rule; 924 925 if (fr == NULL) { 926 int inserr; 927 928 READ_ENTER(&softc->ipf_state); 929 inserr = ipf_state_insert(softc, isn, 0); 930 MUTEX_EXIT(&isn->is_lock); 931 RWLOCK_EXIT(&softc->ipf_state); 932 933 return inserr; 934 } 935 936 if (isn->is_flags & SI_NEWFR) { 937 KMALLOC(fr, frentry_t *); 938 if (fr == NULL) { 939 KFREE(isn); 940 IPFERROR(100024); 941 return ENOMEM; 942 } 943 bcopy((char *)&ips.ips_fr, (char *)fr, sizeof(*fr)); 944 out = fr->fr_flags & FR_OUTQUE ? 1 : 0; 945 isn->is_rule = fr; 946 ips.ips_is.is_rule = fr; 947 MUTEX_NUKE(&fr->fr_lock); 948 MUTEX_INIT(&fr->fr_lock, "state filter rule lock"); 949 950 /* 951 * Look up all the interface names in the rule. 952 */ 953 for (i = 0; i < 4; i++) { 954 if (fr->fr_ifnames[i] == -1) { 955 fr->fr_ifas[i] = NULL; 956 continue; 957 } 958 name = fr->fr_names + fr->fr_ifnames[i]; 959 fr->fr_ifas[i] = ipf_resolvenic(softc, name, 960 fr->fr_family); 961 } 962 963 for (i = 0; i < 4; i++) { 964 name = isn->is_ifname[i]; 965 isn->is_ifp[i] = ipf_resolvenic(softc, name, 966 isn->is_v); 967 } 968 969 fr->fr_ref = 0; 970 fr->fr_dsize = 0; 971 fr->fr_data = NULL; 972 fr->fr_type = FR_T_NONE; 973 974 (void) ipf_resolvedest(softc, fr->fr_names, &fr->fr_tifs[0], 975 fr->fr_family); 976 (void) ipf_resolvedest(softc, fr->fr_names, &fr->fr_tifs[1], 977 fr->fr_family); 978 (void) ipf_resolvedest(softc, fr->fr_names, &fr->fr_dif, 979 fr->fr_family); 980 981 /* 982 * send a copy back to userland of what we ended up 983 * to allow for verification. 984 */ 985 error = ipf_outobj(softc, data, &ips, IPFOBJ_STATESAVE); 986 if (error != 0) { 987 KFREE(isn); 988 MUTEX_DESTROY(&fr->fr_lock); 989 KFREE(fr); 990 IPFERROR(100025); 991 return EFAULT; 992 } 993 READ_ENTER(&softc->ipf_state); 994 error = ipf_state_insert(softc, isn, 0); 995 MUTEX_EXIT(&isn->is_lock); 996 RWLOCK_EXIT(&softc->ipf_state); 997 998 } else { 999 READ_ENTER(&softc->ipf_state); 1000 for (is = softs->ipf_state_list; is; is = is->is_next) 1001 if (is->is_rule == fr) { 1002 error = ipf_state_insert(softc, isn, 0); 1003 MUTEX_EXIT(&isn->is_lock); 1004 break; 1005 } 1006 1007 if (is == NULL) { 1008 KFREE(isn); 1009 isn = NULL; 1010 } 1011 RWLOCK_EXIT(&softc->ipf_state); 1012 1013 if (isn == NULL) { 1014 IPFERROR(100033); 1015 error = ESRCH; 1016 } 1017 } 1018 1019 return error; 1020 } 1021 1022 1023 /* ------------------------------------------------------------------------ */ 1024 /* Function: ipf_state_insert */ 1025 /* Returns: int - 0 == success, -1 == failure */ 1026 /* Parameters: softc(I) - pointer to soft context main structure */ 1027 /* Parameters: is(I) - pointer to state structure */ 1028 /* rev(I) - flag indicating direction of packet */ 1029 /* */ 1030 /* Inserts a state structure into the hash table (for lookups) and the list */ 1031 /* of state entries (for enumeration). Resolves all of the interface names */ 1032 /* to pointers and adjusts running stats for the hash table as appropriate. */ 1033 /* */ 1034 /* This function can fail if the filter rule has had a population policy of */ 1035 /* IP addresses used with stateful filtering assigned to it. */ 1036 /* */ 1037 /* Locking: it is assumed that some kind of lock on ipf_state is held. */ 1038 /* Exits with is_lock initialised and held - *EVEN IF ERROR*. */ 1039 /* ------------------------------------------------------------------------ */ 1040 int 1041 ipf_state_insert(ipf_main_softc_t *softc, ipstate_t *is, int rev) 1042 { 1043 ipf_state_softc_t *softs = softc->ipf_state_soft; 1044 frentry_t *fr; 1045 u_int hv; 1046 int i; 1047 1048 /* 1049 * Look up all the interface names in the state entry. 1050 */ 1051 for (i = 0; i < 4; i++) { 1052 if (is->is_ifp[i] != NULL) 1053 continue; 1054 is->is_ifp[i] = ipf_resolvenic(softc, is->is_ifname[i], 1055 is->is_v); 1056 } 1057 1058 /* 1059 * If we could trust is_hv, then the modulus would not be needed, 1060 * but when running with IPFILTER_SYNC, this stops bad values. 1061 */ 1062 hv = is->is_hv % softs->ipf_state_size; 1063 /* TRACE is, hv */ 1064 is->is_hv = hv; 1065 1066 /* 1067 * We need to get both of these locks...the first because it is 1068 * possible that once the insert is complete another packet might 1069 * come along, match the entry and want to update it. 1070 */ 1071 MUTEX_INIT(&is->is_lock, "ipf state entry"); 1072 MUTEX_ENTER(&is->is_lock); 1073 MUTEX_ENTER(&softs->ipf_stinsert); 1074 1075 fr = is->is_rule; 1076 if (fr != NULL) { 1077 if ((fr->fr_srctrack.ht_max_nodes != 0) && 1078 (ipf_ht_node_add(softc, &fr->fr_srctrack, 1079 is->is_family, &is->is_src) == -1)) { 1080 SBUMPD(ipf_state_stats, iss_max_track); 1081 MUTEX_EXIT(&softs->ipf_stinsert); 1082 return -1; 1083 } 1084 1085 MUTEX_ENTER(&fr->fr_lock); 1086 fr->fr_ref++; 1087 MUTEX_EXIT(&fr->fr_lock); 1088 fr->fr_statecnt++; 1089 } 1090 1091 if (is->is_flags & (SI_WILDP|SI_WILDA)) { 1092 DT(iss_wild_plus_one); 1093 SINCL(ipf_state_stats.iss_wild); 1094 } 1095 1096 SBUMP(ipf_state_stats.iss_proto[is->is_p]); 1097 SBUMP(ipf_state_stats.iss_active_proto[is->is_p]); 1098 1099 /* 1100 * add into list table. 1101 */ 1102 if (softs->ipf_state_list != NULL) 1103 softs->ipf_state_list->is_pnext = &is->is_next; 1104 is->is_pnext = &softs->ipf_state_list; 1105 is->is_next = softs->ipf_state_list; 1106 softs->ipf_state_list = is; 1107 1108 if (softs->ipf_state_table[hv] != NULL) 1109 softs->ipf_state_table[hv]->is_phnext = &is->is_hnext; 1110 else 1111 softs->ipf_state_stats.iss_inuse++; 1112 is->is_phnext = softs->ipf_state_table + hv; 1113 is->is_hnext = softs->ipf_state_table[hv]; 1114 softs->ipf_state_table[hv] = is; 1115 softs->ipf_state_stats.iss_bucketlen[hv]++; 1116 softs->ipf_state_stats.iss_active++; 1117 MUTEX_EXIT(&softs->ipf_stinsert); 1118 1119 ipf_state_setqueue(softc, is, rev); 1120 1121 return 0; 1122 } 1123 1124 1125 /* ------------------------------------------------------------------------ */ 1126 /* Function: ipf_state_matchipv4addrs */ 1127 /* Returns: int - 2 addresses match (strong match), 1 reverse match, */ 1128 /* 0 no match */ 1129 /* Parameters: is1, is2 pointers to states we are checking */ 1130 /* */ 1131 /* Function matches IPv4 addresses it returns strong match for ICMP proto */ 1132 /* even there is only reverse match */ 1133 /* ------------------------------------------------------------------------ */ 1134 static int 1135 ipf_state_matchipv4addrs(ipstate_t *is1, ipstate_t *is2) 1136 { 1137 int rv; 1138 1139 if (is1->is_saddr == is2->is_saddr && is1->is_daddr == is2->is_daddr) 1140 rv = 2; 1141 else if (is1->is_saddr == is2->is_daddr && 1142 is1->is_daddr == is2->is_saddr) { 1143 /* force strong match for ICMP protocol */ 1144 rv = (is1->is_p == IPPROTO_ICMP) ? 2 : 1; 1145 } 1146 else 1147 rv = 0; 1148 1149 return (rv); 1150 } 1151 1152 1153 /* ------------------------------------------------------------------------ */ 1154 /* Function: ipf_state_matchipv6addrs */ 1155 /* Returns: int - 2 addresses match (strong match), 1 reverse match, */ 1156 /* 0 no match */ 1157 /* Parameters: is1, is2 pointers to states we are checking */ 1158 /* */ 1159 /* Function matches IPv6 addresses it returns strong match for ICMP proto */ 1160 /* even there is only reverse match */ 1161 /* ------------------------------------------------------------------------ */ 1162 static int 1163 ipf_state_matchipv6addrs(ipstate_t *is1, ipstate_t *is2) 1164 { 1165 int rv; 1166 1167 if (IP6_EQ(&is1->is_src, &is2->is_src) && 1168 IP6_EQ(&is1->is_dst, &is2->is_dst)) 1169 rv = 2; 1170 else if (IP6_EQ(&is1->is_src, &is2->is_dst) && 1171 IP6_EQ(&is1->is_dst, &is2->is_src)) { 1172 /* force strong match for ICMPv6 protocol */ 1173 rv = (is1->is_p == IPPROTO_ICMPV6) ? 2 : 1; 1174 } 1175 else 1176 rv = 0; 1177 1178 return (rv); 1179 } 1180 1181 1182 /* ------------------------------------------------------------------------ */ 1183 /* Function: ipf_state_matchaddresses */ 1184 /* Returns: int - 2 addresses match, 1 reverse match, zero no match */ 1185 /* Parameters: is1, is2 pointers to states we are checking */ 1186 /* */ 1187 /* function retruns true if two pairs of addresses belong to single */ 1188 /* connection. suppose there are two endpoints: */ 1189 /* endpoint1 1.1.1.1 */ 1190 /* endpoint2 1.1.1.2 */ 1191 /* */ 1192 /* the state is established by packet flying from .1 to .2 so we see: */ 1193 /* is1->src = 1.1.1.1 */ 1194 /* is1->dst = 1.1.1.2 */ 1195 /* now endpoint 1.1.1.2 sends answer */ 1196 /* retreives is1 record created by first packat and compares it with is2 */ 1197 /* temporal record, is2 is initialized as follows: */ 1198 /* is2->src = 1.1.1.2 */ 1199 /* is2->dst = 1.1.1.1 */ 1200 /* in this case 1 will be returned */ 1201 /* */ 1202 /* the ipf_matchaddresses() assumes those two records to be same. of course */ 1203 /* the ipf_matchaddresses() also assume records are same in case you pass */ 1204 /* identical arguments (i.e. ipf_matchaddress(is1, is1) would return 2 */ 1205 /* ------------------------------------------------------------------------ */ 1206 static int 1207 ipf_state_matchaddresses(ipstate_t *is1, ipstate_t *is2) 1208 { 1209 int rv; 1210 1211 if (is1->is_v == 4) { 1212 rv = ipf_state_matchipv4addrs(is1, is2); 1213 } 1214 else { 1215 rv = ipf_state_matchipv6addrs(is1, is2); 1216 } 1217 1218 return (rv); 1219 } 1220 1221 1222 /* ------------------------------------------------------------------------ */ 1223 /* Function: ipf_matchports */ 1224 /* Returns: int - 2 match, 1 rverse match, 0 no match */ 1225 /* Parameters: ppairs1, ppairs - src, dst ports we want to match */ 1226 /* */ 1227 /* performs the same match for isps members as for addresses */ 1228 /* ------------------------------------------------------------------------ */ 1229 static int 1230 ipf_state_matchports(udpinfo_t *ppairs1, udpinfo_t *ppairs2) 1231 { 1232 int rv; 1233 1234 if (ppairs1->us_sport == ppairs2->us_sport && 1235 ppairs1->us_dport == ppairs2->us_dport) 1236 rv = 2; 1237 else if (ppairs1->us_sport == ppairs2->us_dport && 1238 ppairs1->us_dport == ppairs2->us_sport) 1239 rv = 1; 1240 else 1241 rv = 0; 1242 1243 return (rv); 1244 } 1245 1246 1247 /* ------------------------------------------------------------------------ */ 1248 /* Function: ipf_matchisps */ 1249 /* Returns: int - nonzero if isps members match, 0 nomatch */ 1250 /* Parameters: is1, is2 - states we want to match */ 1251 /* */ 1252 /* performs the same match for isps members as for addresses */ 1253 /* ------------------------------------------------------------------------ */ 1254 static int 1255 ipf_state_matchisps(ipstate_t *is1, ipstate_t *is2) 1256 { 1257 int rv; 1258 1259 if (is1->is_p == is2->is_p) { 1260 switch (is1->is_p) 1261 { 1262 case IPPROTO_TCP : 1263 case IPPROTO_UDP : 1264 case IPPROTO_GRE : 1265 /* greinfo_t can be also interprted as port pair */ 1266 rv = ipf_state_matchports(&is1->is_ps.is_us, 1267 &is2->is_ps.is_us); 1268 break; 1269 1270 case IPPROTO_ICMP : 1271 case IPPROTO_ICMPV6 : 1272 /* force strong match for ICMP datagram. */ 1273 if (bcmp(&is1->is_ps, &is2->is_ps, 1274 sizeof(icmpinfo_t)) == 0) { 1275 rv = 2; 1276 } else { 1277 rv = 0; 1278 } 1279 break; 1280 1281 default: 1282 rv = 0; 1283 } 1284 } else { 1285 rv = 0; 1286 } 1287 1288 return (rv); 1289 } 1290 1291 1292 /* ------------------------------------------------------------------------ */ 1293 /* Function: ipf_state_match */ 1294 /* Returns: int - nonzero match, zero no match */ 1295 /* Parameters: is1, is2 - states we want to match */ 1296 /* */ 1297 /* ------------------------------------------------------------------------ */ 1298 static int 1299 ipf_state_match(ipstate_t *is1, ipstate_t *is2) 1300 { 1301 int rv; 1302 int amatch; 1303 int pomatch; 1304 1305 if (bcmp(&is1->is_pass, &is2->is_pass, 1306 offsetof(struct ipstate, is_authmsk) - 1307 offsetof(struct ipstate, is_pass)) == 0) { 1308 1309 pomatch = ipf_state_matchisps(is1, is2); 1310 amatch = ipf_state_matchaddresses(is1, is2); 1311 rv = (amatch != 0) && (amatch == pomatch); 1312 } else { 1313 rv = 0; 1314 } 1315 1316 return (rv); 1317 } 1318 1319 /* ------------------------------------------------------------------------ */ 1320 /* Function: ipf_state_add */ 1321 /* Returns: ipstate_t - 0 = success */ 1322 /* Parameters: softc(I) - pointer to soft context main structure */ 1323 /* fin(I) - pointer to packet information */ 1324 /* stsave(O) - pointer to place to save pointer to created */ 1325 /* state structure. */ 1326 /* flags(I) - flags to use when creating the structure */ 1327 /* */ 1328 /* Creates a new IP state structure from the packet information collected. */ 1329 /* Inserts it into the state table and appends to the bottom of the active */ 1330 /* list. If the capacity of the table has reached the maximum allowed then */ 1331 /* the call will fail and a flush is scheduled for the next timeout call. */ 1332 /* */ 1333 /* NOTE: The use of stsave to point to nat_state will result in memory */ 1334 /* corruption. It should only be used to point to objects that will */ 1335 /* either outlive this (not expired) or will deref the ip_state_t */ 1336 /* when they are deleted. */ 1337 /* ------------------------------------------------------------------------ */ 1338 int 1339 ipf_state_add(ipf_main_softc_t *softc, fr_info_t *fin, ipstate_t **stsave, 1340 u_int flags) 1341 { 1342 ipf_state_softc_t *softs = softc->ipf_state_soft; 1343 ipstate_t *is, ips; 1344 struct icmp *ic; 1345 u_int pass, hv; 1346 frentry_t *fr; 1347 tcphdr_t *tcp; 1348 frdest_t *fdp; 1349 int out; 1350 1351 /* 1352 * If a packet that was created locally is trying to go out but we 1353 * do not match here here because of this lock, it is likely that 1354 * the policy will block it and return network unreachable back up 1355 * the stack. To mitigate this error, EAGAIN is returned instead, 1356 * telling the IP stack to try sending this packet again later. 1357 */ 1358 if (softs->ipf_state_lock) { 1359 SBUMPD(ipf_state_stats, iss_add_locked); 1360 fin->fin_error = EAGAIN; 1361 return -1; 1362 } 1363 1364 if (fin->fin_flx & (FI_SHORT|FI_STATE|FI_FRAGBODY|FI_BAD)) { 1365 SBUMPD(ipf_state_stats, iss_add_bad); 1366 return -1; 1367 } 1368 1369 if ((fin->fin_flx & FI_OOW) && !(fin->fin_tcpf & TH_SYN)) { 1370 SBUMPD(ipf_state_stats, iss_add_oow); 1371 return -1; 1372 } 1373 1374 if ((softs->ipf_state_stats.iss_active * 100 / softs->ipf_state_max) > 1375 softs->ipf_state_wm_high) { 1376 softs->ipf_state_doflush = 1; 1377 } 1378 1379 /* 1380 * If a "keep state" rule has reached the maximum number of references 1381 * to it, then schedule an automatic flush in case we can clear out 1382 * some "dead old wood". Note that because the lock isn't held on 1383 * fr it is possible that we could overflow. The cost of overflowing 1384 * is being ignored here as the number by which it can overflow is 1385 * a product of the number of simultaneous threads that could be 1386 * executing in here, so a limit of 100 won't result in 200, but could 1387 * result in 101 or 102. 1388 */ 1389 fr = fin->fin_fr; 1390 if (fr != NULL) { 1391 if ((softs->ipf_state_stats.iss_active >= 1392 softs->ipf_state_max) && (fr->fr_statemax == 0)) { 1393 SBUMPD(ipf_state_stats, iss_max); 1394 return 1; 1395 } 1396 if ((fr->fr_statemax != 0) && 1397 (fr->fr_statecnt >= fr->fr_statemax)) { 1398 SBUMPD(ipf_state_stats, iss_max_ref); 1399 return 2; 1400 } 1401 } 1402 1403 is = &ips; 1404 if (fr == NULL) { 1405 pass = softc->ipf_flags; 1406 is->is_tag = FR_NOLOGTAG; 1407 } else { 1408 pass = fr->fr_flags; 1409 } 1410 1411 ic = NULL; 1412 tcp = NULL; 1413 out = fin->fin_out; 1414 bzero((char *)is, sizeof(*is)); 1415 is->is_die = 1 + softc->ipf_ticks; 1416 /* 1417 * We want to check everything that is a property of this packet, 1418 * but we don't (automatically) care about it's fragment status as 1419 * this may change. 1420 */ 1421 is->is_pass = pass; 1422 is->is_v = fin->fin_v; 1423 is->is_sec = fin->fin_secmsk; 1424 is->is_secmsk = 0xffff; 1425 is->is_auth = fin->fin_auth; 1426 is->is_authmsk = 0xffff; 1427 is->is_family = fin->fin_family; 1428 is->is_opt[0] = fin->fin_optmsk; 1429 is->is_optmsk[0] = 0xffffffff; 1430 if (is->is_v == 6) { 1431 is->is_opt[0] &= ~0x8; 1432 is->is_optmsk[0] &= ~0x8; 1433 } 1434 1435 /* 1436 * Copy and calculate... 1437 */ 1438 hv = (is->is_p = fin->fin_fi.fi_p); 1439 is->is_src = fin->fin_fi.fi_src; 1440 hv += is->is_saddr; 1441 is->is_dst = fin->fin_fi.fi_dst; 1442 hv += is->is_daddr; 1443 #ifdef USE_INET6 1444 if (fin->fin_v == 6) { 1445 /* 1446 * For ICMPv6, we check to see if the destination address is 1447 * a multicast address. If it is, do not include it in the 1448 * calculation of the hash because the correct reply will come 1449 * back from a real address, not a multicast address. 1450 */ 1451 if ((is->is_p == IPPROTO_ICMPV6) && 1452 IN6_IS_ADDR_MULTICAST(&is->is_dst.in6)) { 1453 /* 1454 * So you can do keep state with neighbour discovery. 1455 * 1456 * Here we could use the address from the neighbour 1457 * solicit message to put in the state structure and 1458 * we could use that without a wildcard flag too... 1459 */ 1460 flags |= SI_W_DADDR; 1461 hv -= is->is_daddr; 1462 } else { 1463 hv += is->is_dst.i6[1]; 1464 hv += is->is_dst.i6[2]; 1465 hv += is->is_dst.i6[3]; 1466 } 1467 hv += is->is_src.i6[1]; 1468 hv += is->is_src.i6[2]; 1469 hv += is->is_src.i6[3]; 1470 } 1471 #endif 1472 if ((fin->fin_v == 4) && 1473 (fin->fin_flx & (FI_MULTICAST|FI_BROADCAST|FI_MBCAST))) { 1474 flags |= SI_W_DADDR; 1475 hv -= is->is_daddr; 1476 } 1477 1478 switch (is->is_p) 1479 { 1480 #ifdef USE_INET6 1481 case IPPROTO_ICMPV6 : 1482 ic = fin->fin_dp; 1483 1484 switch (ic->icmp_type) 1485 { 1486 case ICMP6_ECHO_REQUEST : 1487 hv += (is->is_icmp.ici_id = ic->icmp_id); 1488 /*FALLTHROUGH*/ 1489 case ICMP6_MEMBERSHIP_QUERY : 1490 case ND_ROUTER_SOLICIT : 1491 case ND_NEIGHBOR_SOLICIT : 1492 case ICMP6_NI_QUERY : 1493 is->is_icmp.ici_type = ic->icmp_type; 1494 break; 1495 default : 1496 SBUMPD(ipf_state_stats, iss_icmp6_notquery); 1497 return -2; 1498 } 1499 break; 1500 #endif 1501 case IPPROTO_ICMP : 1502 ic = fin->fin_dp; 1503 1504 switch (ic->icmp_type) 1505 { 1506 case ICMP_ECHO : 1507 case ICMP_TSTAMP : 1508 case ICMP_IREQ : 1509 case ICMP_MASKREQ : 1510 is->is_icmp.ici_type = ic->icmp_type; 1511 hv += (is->is_icmp.ici_id = ic->icmp_id); 1512 break; 1513 default : 1514 SBUMPD(ipf_state_stats, iss_icmp_notquery); 1515 return -3; 1516 } 1517 break; 1518 1519 #if 0 1520 case IPPROTO_GRE : 1521 gre = fin->fin_dp; 1522 1523 is->is_gre.gs_flags = gre->gr_flags; 1524 is->is_gre.gs_ptype = gre->gr_ptype; 1525 if (GRE_REV(is->is_gre.gs_flags) == 1) { 1526 is->is_call[0] = fin->fin_data[0]; 1527 is->is_call[1] = fin->fin_data[1]; 1528 } 1529 break; 1530 #endif 1531 1532 case IPPROTO_TCP : 1533 tcp = fin->fin_dp; 1534 1535 if (tcp->th_flags & TH_RST) { 1536 SBUMPD(ipf_state_stats, iss_tcp_rstadd); 1537 return -4; 1538 } 1539 1540 /* TRACE is, flags, hv */ 1541 1542 /* 1543 * The endian of the ports doesn't matter, but the ack and 1544 * sequence numbers do as we do mathematics on them later. 1545 */ 1546 is->is_sport = htons(fin->fin_data[0]); 1547 is->is_dport = htons(fin->fin_data[1]); 1548 if ((flags & (SI_W_DPORT|SI_W_SPORT)) == 0) { 1549 hv += is->is_sport; 1550 hv += is->is_dport; 1551 } 1552 1553 /* TRACE is, flags, hv */ 1554 1555 /* 1556 * If this is a real packet then initialise fields in the 1557 * state information structure from the TCP header information. 1558 */ 1559 1560 is->is_maxdwin = 1; 1561 is->is_maxswin = ntohs(tcp->th_win); 1562 if (is->is_maxswin == 0) 1563 is->is_maxswin = 1; 1564 1565 if ((fin->fin_flx & FI_IGNORE) == 0) { 1566 is->is_send = ntohl(tcp->th_seq) + fin->fin_dlen - 1567 (TCP_OFF(tcp) << 2) + 1568 ((tcp->th_flags & TH_SYN) ? 1 : 0) + 1569 ((tcp->th_flags & TH_FIN) ? 1 : 0); 1570 is->is_maxsend = is->is_send; 1571 1572 /* 1573 * Window scale option is only present in 1574 * SYN/SYN-ACK packet. 1575 */ 1576 if ((tcp->th_flags & ~(TH_FIN|TH_ACK|TH_ECNALL)) == 1577 TH_SYN && 1578 (TCP_OFF(tcp) > (sizeof(tcphdr_t) >> 2))) { 1579 if (ipf_tcpoptions(softs, fin, tcp, 1580 &is->is_tcp.ts_data[0]) == -1) 1581 fin->fin_flx |= FI_BAD; 1582 } 1583 1584 if ((fin->fin_out != 0) && (pass & FR_NEWISN) != 0) { 1585 ipf_checknewisn(fin, is); 1586 ipf_fixoutisn(fin, is); 1587 } 1588 1589 if ((tcp->th_flags & TH_OPENING) == TH_SYN) 1590 flags |= IS_TCPFSM; 1591 else { 1592 is->is_maxdwin = is->is_maxswin * 2; 1593 is->is_dend = ntohl(tcp->th_ack); 1594 is->is_maxdend = ntohl(tcp->th_ack); 1595 is->is_maxdwin *= 2; 1596 } 1597 } 1598 1599 /* 1600 * If we're creating state for a starting connection, start 1601 * the timer on it as we'll never see an error if it fails 1602 * to connect. 1603 */ 1604 break; 1605 1606 case IPPROTO_UDP : 1607 tcp = fin->fin_dp; 1608 1609 is->is_sport = htons(fin->fin_data[0]); 1610 is->is_dport = htons(fin->fin_data[1]); 1611 if ((flags & (SI_W_DPORT|SI_W_SPORT)) == 0) { 1612 hv += tcp->th_dport; 1613 hv += tcp->th_sport; 1614 } 1615 break; 1616 1617 default : 1618 break; 1619 } 1620 hv = DOUBLE_HASH(hv); 1621 is->is_hv = hv; 1622 1623 /* 1624 * Look for identical state. 1625 */ 1626 for (is = softs->ipf_state_table[hv % softs->ipf_state_size]; 1627 is != NULL; is = is->is_hnext) { 1628 if (ipf_state_match(&ips, is) == 1) 1629 break; 1630 } 1631 if (is != NULL) { 1632 SBUMPD(ipf_state_stats, iss_add_dup); 1633 return 3; 1634 } 1635 1636 if (softs->ipf_state_stats.iss_bucketlen[hv] >= 1637 softs->ipf_state_maxbucket) { 1638 SBUMPD(ipf_state_stats, iss_bucket_full); 1639 return 4; 1640 } 1641 1642 /* 1643 * No existing state; create new 1644 */ 1645 KMALLOC(is, ipstate_t *); 1646 if (is == NULL) { 1647 SBUMPD(ipf_state_stats, iss_nomem); 1648 return 5; 1649 } 1650 bcopy((char *)&ips, (char *)is, sizeof(*is)); 1651 is->is_flags = flags & IS_INHERITED; 1652 is->is_rulen = fin->fin_rule; 1653 is->is_rule = fr; 1654 1655 /* 1656 * Do not do the modulus here, it is done in ipf_state_insert(). 1657 */ 1658 if (fr != NULL) { 1659 ipftq_t *tq; 1660 1661 (void) strncpy(is->is_group, FR_NAME(fr, fr_group), 1662 FR_GROUPLEN); 1663 if (fr->fr_age[0] != 0) { 1664 tq = ipf_addtimeoutqueue(softc, 1665 &softs->ipf_state_usertq, 1666 fr->fr_age[0]); 1667 is->is_tqehead[0] = tq; 1668 is->is_sti.tqe_flags |= TQE_RULEBASED; 1669 } 1670 if (fr->fr_age[1] != 0) { 1671 tq = ipf_addtimeoutqueue(softc, 1672 &softs->ipf_state_usertq, 1673 fr->fr_age[1]); 1674 is->is_tqehead[1] = tq; 1675 is->is_sti.tqe_flags |= TQE_RULEBASED; 1676 } 1677 1678 is->is_tag = fr->fr_logtag; 1679 } 1680 1681 /* 1682 * It may seem strange to set is_ref to 2, but if stsave is not NULL 1683 * then a copy of the pointer is being stored somewhere else and in 1684 * the end, it will expect to be able to do something with it. 1685 */ 1686 is->is_me = stsave; 1687 if (stsave != NULL) { 1688 *stsave = is; 1689 is->is_ref = 2; 1690 } else { 1691 is->is_ref = 1; 1692 } 1693 is->is_pkts[0] = 0, is->is_bytes[0] = 0; 1694 is->is_pkts[1] = 0, is->is_bytes[1] = 0; 1695 is->is_pkts[2] = 0, is->is_bytes[2] = 0; 1696 is->is_pkts[3] = 0, is->is_bytes[3] = 0; 1697 if ((fin->fin_flx & FI_IGNORE) == 0) { 1698 is->is_pkts[out] = 1; 1699 fin->fin_pktnum = 1; 1700 is->is_bytes[out] = fin->fin_plen; 1701 is->is_flx[out][0] = fin->fin_flx & FI_CMP; 1702 is->is_flx[out][0] &= ~FI_OOW; 1703 } 1704 1705 if (pass & FR_STLOOSE) 1706 is->is_flags |= IS_LOOSE; 1707 1708 if (pass & FR_STSTRICT) 1709 is->is_flags |= IS_STRICT; 1710 1711 if (pass & FR_STATESYNC) 1712 is->is_flags |= IS_STATESYNC; 1713 1714 if (pass & FR_LOGFIRST) 1715 is->is_pass &= ~(FR_LOGFIRST|FR_LOG); 1716 1717 READ_ENTER(&softc->ipf_state); 1718 1719 if (ipf_state_insert(softc, is, fin->fin_rev) == -1) { 1720 RWLOCK_EXIT(&softc->ipf_state); 1721 /* 1722 * This is a bit more manual than it should be but 1723 * ipf_state_del cannot be called. 1724 */ 1725 MUTEX_EXIT(&is->is_lock); 1726 MUTEX_DESTROY(&is->is_lock); 1727 if (is->is_tqehead[0] != NULL) { 1728 if (ipf_deletetimeoutqueue(is->is_tqehead[0]) == 0) 1729 ipf_freetimeoutqueue(softc, is->is_tqehead[0]); 1730 is->is_tqehead[0] = NULL; 1731 } 1732 if (is->is_tqehead[1] != NULL) { 1733 if (ipf_deletetimeoutqueue(is->is_tqehead[1]) == 0) 1734 ipf_freetimeoutqueue(softc, is->is_tqehead[1]); 1735 is->is_tqehead[1] = NULL; 1736 } 1737 KFREE(is); 1738 return -1; 1739 } 1740 1741 /* 1742 * Filling in the interface name is after the insert so that an 1743 * event (such as add/delete) of an interface that is referenced 1744 * by this rule will see this state entry. 1745 */ 1746 if (fr != NULL) { 1747 /* 1748 * The name '-' is special for network interfaces and causes 1749 * a NULL name to be present, always, allowing packets to 1750 * match it, regardless of their interface. 1751 */ 1752 if ((fin->fin_ifp == NULL) || 1753 (fr->fr_ifnames[out << 1] != -1 && 1754 fr->fr_names[fr->fr_ifnames[out << 1] + 0] == '-' && 1755 fr->fr_names[fr->fr_ifnames[out << 1] + 1] == '\0')) { 1756 is->is_ifp[out << 1] = fr->fr_ifas[0]; 1757 strncpy(is->is_ifname[out << 1], 1758 fr->fr_names + fr->fr_ifnames[0], 1759 sizeof(fr->fr_ifnames[0])); 1760 } else { 1761 is->is_ifp[out << 1] = fin->fin_ifp; 1762 COPYIFNAME(fin->fin_v, fin->fin_ifp, 1763 is->is_ifname[out << 1]); 1764 } 1765 1766 is->is_ifp[(out << 1) + 1] = fr->fr_ifas[1]; 1767 if (fr->fr_ifnames[1] != -1) { 1768 strncpy(is->is_ifname[(out << 1) + 1], 1769 fr->fr_names + fr->fr_ifnames[1], 1770 sizeof(fr->fr_ifnames[1])); 1771 } 1772 1773 is->is_ifp[(1 - out) << 1] = fr->fr_ifas[2]; 1774 if (fr->fr_ifnames[2] != -1) { 1775 strncpy(is->is_ifname[((1 - out) << 1)], 1776 fr->fr_names + fr->fr_ifnames[2], 1777 sizeof(fr->fr_ifnames[2])); 1778 } 1779 1780 is->is_ifp[((1 - out) << 1) + 1] = fr->fr_ifas[3]; 1781 if (fr->fr_ifnames[3] != -1) { 1782 strncpy(is->is_ifname[((1 - out) << 1) + 1], 1783 fr->fr_names + fr->fr_ifnames[3], 1784 sizeof(fr->fr_ifnames[3])); 1785 } 1786 } else { 1787 if (fin->fin_ifp != NULL) { 1788 is->is_ifp[out << 1] = fin->fin_ifp; 1789 COPYIFNAME(fin->fin_v, fin->fin_ifp, 1790 is->is_ifname[out << 1]); 1791 } 1792 } 1793 1794 if (fin->fin_p == IPPROTO_TCP) { 1795 /* 1796 * If we're creating state for a starting connection, start the 1797 * timer on it as we'll never see an error if it fails to 1798 * connect. 1799 */ 1800 (void) ipf_tcp_age(&is->is_sti, fin, softs->ipf_state_tcptq, 1801 is->is_flags, 2); 1802 } 1803 MUTEX_EXIT(&is->is_lock); 1804 if ((is->is_flags & IS_STATESYNC) && ((is->is_flags & SI_CLONE) == 0)) 1805 is->is_sync = ipf_sync_new(softc, SMC_STATE, fin, is); 1806 if (softs->ipf_state_logging) 1807 ipf_state_log(softc, is, ISL_NEW); 1808 1809 RWLOCK_EXIT(&softc->ipf_state); 1810 1811 fin->fin_flx |= FI_STATE; 1812 if (fin->fin_flx & FI_FRAG) 1813 (void) ipf_frag_new(softc, fin, pass); 1814 1815 fdp = &fr->fr_tifs[0]; 1816 if (fdp->fd_type == FRD_DSTLIST) { 1817 ipf_dstlist_select_node(fin, fdp->fd_ptr, NULL, 1818 &is->is_tifs[0]); 1819 } else { 1820 bcopy(fdp, &is->is_tifs[0], sizeof(*fdp)); 1821 } 1822 1823 fdp = &fr->fr_tifs[1]; 1824 if (fdp->fd_type == FRD_DSTLIST) { 1825 ipf_dstlist_select_node(fin, fdp->fd_ptr, NULL, 1826 &is->is_tifs[1]); 1827 } else { 1828 bcopy(fdp, &is->is_tifs[1], sizeof(*fdp)); 1829 } 1830 fin->fin_tif = &is->is_tifs[fin->fin_rev]; 1831 1832 fdp = &fr->fr_dif; 1833 if (fdp->fd_type == FRD_DSTLIST) { 1834 ipf_dstlist_select_node(fin, fdp->fd_ptr, NULL, 1835 &is->is_dif); 1836 } else { 1837 bcopy(fdp, &is->is_dif, sizeof(*fdp)); 1838 } 1839 fin->fin_dif = &is->is_dif; 1840 1841 return 0; 1842 } 1843 1844 1845 /* ------------------------------------------------------------------------ */ 1846 /* Function: ipf_tcpoptions */ 1847 /* Returns: int - 1 == packet matches state entry, 0 == it does not, */ 1848 /* -1 == packet has bad TCP options data */ 1849 /* Parameters: softs(I) - pointer to state context structure */ 1850 /* fin(I) - pointer to packet information */ 1851 /* tcp(I) - pointer to TCP packet header */ 1852 /* td(I) - pointer to TCP data held as part of the state */ 1853 /* */ 1854 /* Look after the TCP header for any options and deal with those that are */ 1855 /* present. Record details about those that we recogise. */ 1856 /* ------------------------------------------------------------------------ */ 1857 static int 1858 ipf_tcpoptions(ipf_state_softc_t *softs, fr_info_t *fin, tcphdr_t *tcp, 1859 tcpdata_t *td) 1860 { 1861 int off, mlen, ol, i, len, retval; 1862 char buf[64], *s, opt; 1863 mb_t *m = NULL; 1864 1865 len = (TCP_OFF(tcp) << 2); 1866 if (fin->fin_dlen < len) { 1867 SBUMPD(ipf_state_stats, iss_tcp_toosmall); 1868 return 0; 1869 } 1870 len -= sizeof(*tcp); 1871 1872 off = fin->fin_plen - fin->fin_dlen + sizeof(*tcp) + fin->fin_ipoff; 1873 1874 m = fin->fin_m; 1875 mlen = MSGDSIZE(m) - off; 1876 if (len > mlen) { 1877 len = mlen; 1878 retval = 0; 1879 } else { 1880 retval = 1; 1881 } 1882 1883 COPYDATA(m, off, len, buf); 1884 1885 for (s = buf; len > 0; ) { 1886 opt = *s; 1887 if (opt == TCPOPT_EOL) 1888 break; 1889 else if (opt == TCPOPT_NOP) 1890 ol = 1; 1891 else { 1892 if (len < 2) 1893 break; 1894 ol = (int)*(s + 1); 1895 if (ol < 2 || ol > len) 1896 break; 1897 1898 /* 1899 * Extract the TCP options we are interested in out of 1900 * the header and store them in the tcpdata struct. 1901 */ 1902 switch (opt) 1903 { 1904 case TCPOPT_WINDOW : 1905 if (ol == TCPOLEN_WINDOW) { 1906 i = (int)*(s + 2); 1907 if (i > TCP_WSCALE_MAX) 1908 i = TCP_WSCALE_MAX; 1909 else if (i < 0) 1910 i = 0; 1911 td->td_winscale = i; 1912 td->td_winflags |= TCP_WSCALE_SEEN| 1913 TCP_WSCALE_FIRST; 1914 } else 1915 retval = -1; 1916 break; 1917 case TCPOPT_MAXSEG : 1918 /* 1919 * So, if we wanted to set the TCP MAXSEG, 1920 * it should be done here... 1921 */ 1922 if (ol == TCPOLEN_MAXSEG) { 1923 i = (int)*(s + 2); 1924 i <<= 8; 1925 i += (int)*(s + 3); 1926 td->td_maxseg = i; 1927 } else 1928 retval = -1; 1929 break; 1930 case TCPOPT_SACK_PERMITTED : 1931 if (ol == TCPOLEN_SACK_PERMITTED) 1932 td->td_winflags |= TCP_SACK_PERMIT; 1933 else 1934 retval = -1; 1935 break; 1936 } 1937 } 1938 len -= ol; 1939 s += ol; 1940 } 1941 if (retval == -1) { 1942 SBUMPD(ipf_state_stats, iss_tcp_badopt); 1943 } 1944 return retval; 1945 } 1946 1947 1948 /* ------------------------------------------------------------------------ */ 1949 /* Function: ipf_state_tcp */ 1950 /* Returns: int - 1 == packet matches state entry, 0 == it does not */ 1951 /* Parameters: softc(I) - pointer to soft context main structure */ 1952 /* softs(I) - pointer to state context structure */ 1953 /* fin(I) - pointer to packet information */ 1954 /* tcp(I) - pointer to TCP packet header */ 1955 /* is(I) - pointer to master state structure */ 1956 /* */ 1957 /* Check to see if a packet with TCP headers fits within the TCP window. */ 1958 /* Change timeout depending on whether new packet is a SYN-ACK returning */ 1959 /* for a SYN or a RST or FIN which indicate time to close up shop. */ 1960 /* ------------------------------------------------------------------------ */ 1961 static int 1962 ipf_state_tcp(ipf_main_softc_t *softc, ipf_state_softc_t *softs, fr_info_t *fin, 1963 tcphdr_t *tcp, ipstate_t *is) 1964 { 1965 tcpdata_t *fdata, *tdata; 1966 int source, ret, flags; 1967 1968 source = !fin->fin_rev; 1969 if (((is->is_flags & IS_TCPFSM) != 0) && (source == 1) && 1970 (ntohs(is->is_sport) != fin->fin_data[0])) 1971 source = 0; 1972 fdata = &is->is_tcp.ts_data[!source]; 1973 tdata = &is->is_tcp.ts_data[source]; 1974 1975 MUTEX_ENTER(&is->is_lock); 1976 1977 /* 1978 * If a SYN packet is received for a connection that is on the way out 1979 * but hasn't yet departed then advance this session along the way. 1980 */ 1981 if ((tcp->th_flags & TH_OPENING) == TH_SYN) { 1982 if ((is->is_state[0] > IPF_TCPS_ESTABLISHED) && 1983 (is->is_state[1] > IPF_TCPS_ESTABLISHED)) { 1984 is->is_state[!source] = IPF_TCPS_CLOSED; 1985 ipf_movequeue(softc->ipf_ticks, &is->is_sti, 1986 is->is_sti.tqe_ifq, 1987 &softs->ipf_state_deletetq); 1988 MUTEX_EXIT(&is->is_lock); 1989 DT1(iss_tcp_closing, ipstate_t *, is); 1990 SBUMP(ipf_state_stats.iss_tcp_closing); 1991 return 0; 1992 } 1993 } 1994 1995 if (is->is_flags & IS_LOOSE) 1996 ret = 1; 1997 else 1998 ret = ipf_state_tcpinwindow(fin, fdata, tdata, tcp, 1999 is->is_flags); 2000 if (ret > 0) { 2001 /* 2002 * Nearing end of connection, start timeout. 2003 */ 2004 ret = ipf_tcp_age(&is->is_sti, fin, softs->ipf_state_tcptq, 2005 is->is_flags, ret); 2006 if (ret == 0) { 2007 MUTEX_EXIT(&is->is_lock); 2008 DT2(iss_tcp_fsm, fr_info_t *, fin, ipstate_t *, is); 2009 SBUMP(ipf_state_stats.iss_tcp_fsm); 2010 return 0; 2011 } 2012 2013 if (softs->ipf_state_logging > 4) 2014 ipf_state_log(softc, is, ISL_STATECHANGE); 2015 2016 /* 2017 * set s0's as appropriate. Use syn-ack packet as it 2018 * contains both pieces of required information. 2019 */ 2020 /* 2021 * Window scale option is only present in SYN/SYN-ACK packet. 2022 * Compare with ~TH_FIN to mask out T/TCP setups. 2023 */ 2024 flags = tcp->th_flags & ~(TH_FIN|TH_ECNALL); 2025 if (flags == (TH_SYN|TH_ACK)) { 2026 is->is_s0[source] = ntohl(tcp->th_ack); 2027 is->is_s0[!source] = ntohl(tcp->th_seq) + 1; 2028 if ((TCP_OFF(tcp) > (sizeof(tcphdr_t) >> 2))) { 2029 if (ipf_tcpoptions(softs, fin, tcp, 2030 fdata) == -1) 2031 fin->fin_flx |= FI_BAD; 2032 } 2033 if ((fin->fin_out != 0) && (is->is_pass & FR_NEWISN)) 2034 ipf_checknewisn(fin, is); 2035 } else if (flags == TH_SYN) { 2036 is->is_s0[source] = ntohl(tcp->th_seq) + 1; 2037 if ((TCP_OFF(tcp) > (sizeof(tcphdr_t) >> 2))) { 2038 if (ipf_tcpoptions(softs, fin, tcp, 2039 fdata) == -1) 2040 fin->fin_flx |= FI_BAD; 2041 } 2042 2043 if ((fin->fin_out != 0) && (is->is_pass & FR_NEWISN)) 2044 ipf_checknewisn(fin, is); 2045 2046 } 2047 ret = 1; 2048 } else { 2049 DT2(iss_tcp_oow, fr_info_t *, fin, ipstate_t *, is); 2050 SBUMP(ipf_state_stats.iss_tcp_oow); 2051 ret = 0; 2052 } 2053 MUTEX_EXIT(&is->is_lock); 2054 return ret; 2055 } 2056 2057 2058 /* ------------------------------------------------------------------------ */ 2059 /* Function: ipf_checknewisn */ 2060 /* Returns: Nil */ 2061 /* Parameters: fin(I) - pointer to packet information */ 2062 /* is(I) - pointer to master state structure */ 2063 /* */ 2064 /* Check to see if this TCP connection is expecting and needs a new */ 2065 /* sequence number for a particular direction of the connection. */ 2066 /* */ 2067 /* NOTE: This does not actually change the sequence numbers, only gets new */ 2068 /* one ready. */ 2069 /* ------------------------------------------------------------------------ */ 2070 static void 2071 ipf_checknewisn(fr_info_t *fin, ipstate_t *is) 2072 { 2073 u_32_t sumd, old, new; 2074 tcphdr_t *tcp; 2075 int i; 2076 2077 i = fin->fin_rev; 2078 tcp = fin->fin_dp; 2079 2080 if (((i == 0) && !(is->is_flags & IS_ISNSYN)) || 2081 ((i == 1) && !(is->is_flags & IS_ISNACK))) { 2082 old = ntohl(tcp->th_seq); 2083 new = ipf_newisn(fin); 2084 is->is_isninc[i] = new - old; 2085 CALC_SUMD(old, new, sumd); 2086 is->is_sumd[i] = (sumd & 0xffff) + (sumd >> 16); 2087 2088 is->is_flags |= ((i == 0) ? IS_ISNSYN : IS_ISNACK); 2089 } 2090 } 2091 2092 2093 /* ------------------------------------------------------------------------ */ 2094 /* Function: ipf_state_tcpinwindow */ 2095 /* Returns: int - 1 == packet inside TCP "window", 0 == not inside. */ 2096 /* Parameters: fin(I) - pointer to packet information */ 2097 /* fdata(I) - pointer to tcp state informatio (forward) */ 2098 /* tdata(I) - pointer to tcp state informatio (reverse) */ 2099 /* tcp(I) - pointer to TCP packet header */ 2100 /* */ 2101 /* Given a packet has matched addresses and ports, check to see if it is */ 2102 /* within the TCP data window. In a show of generosity, allow packets that */ 2103 /* are within the window space behind the current sequence # as well. */ 2104 /* ------------------------------------------------------------------------ */ 2105 static int 2106 ipf_state_tcpinwindow(fr_info_t *fin, tcpdata_t *fdata, tcpdata_t *tdata, 2107 tcphdr_t *tcp, int flags) 2108 { 2109 ipf_main_softc_t *softc = fin->fin_main_soft; 2110 ipf_state_softc_t *softs = softc->ipf_state_soft; 2111 tcp_seq seq, ack, end; 2112 int ackskew, tcpflags; 2113 u_32_t win, maxwin; 2114 int dsize, inseq; 2115 2116 /* 2117 * Find difference between last checked packet and this packet. 2118 */ 2119 tcpflags = tcp->th_flags; 2120 seq = ntohl(tcp->th_seq); 2121 ack = ntohl(tcp->th_ack); 2122 if (tcpflags & TH_SYN) 2123 win = ntohs(tcp->th_win); 2124 else 2125 win = ntohs(tcp->th_win) << fdata->td_winscale; 2126 2127 /* 2128 * A window of 0 produces undesirable behaviour from this function. 2129 */ 2130 if (win == 0) 2131 win = 1; 2132 2133 dsize = fin->fin_dlen - (TCP_OFF(tcp) << 2) + 2134 ((tcpflags & TH_SYN) ? 1 : 0) + ((tcpflags & TH_FIN) ? 1 : 0); 2135 2136 /* 2137 * if window scaling is present, the scaling is only allowed 2138 * for windows not in the first SYN packet. In that packet the 2139 * window is 65535 to specify the largest window possible 2140 * for receivers not implementing the window scale option. 2141 * Currently, we do not assume TTCP here. That means that 2142 * if we see a second packet from a host (after the initial 2143 * SYN), we can assume that the receiver of the SYN did 2144 * already send back the SYN/ACK (and thus that we know if 2145 * the receiver also does window scaling) 2146 */ 2147 if (!(tcpflags & TH_SYN) && (fdata->td_winflags & TCP_WSCALE_FIRST)) { 2148 fdata->td_winflags &= ~TCP_WSCALE_FIRST; 2149 fdata->td_maxwin = win; 2150 } 2151 2152 end = seq + dsize; 2153 2154 if ((fdata->td_end == 0) && 2155 (!(flags & IS_TCPFSM) || 2156 ((tcpflags & TH_OPENING) == TH_OPENING))) { 2157 /* 2158 * Must be a (outgoing) SYN-ACK in reply to a SYN. 2159 */ 2160 fdata->td_end = end - 1; 2161 fdata->td_maxwin = 1; 2162 fdata->td_maxend = end + win; 2163 } 2164 2165 if (!(tcpflags & TH_ACK)) { /* Pretend an ack was sent */ 2166 ack = tdata->td_end; 2167 } else if (((tcpflags & (TH_ACK|TH_RST)) == (TH_ACK|TH_RST)) && 2168 (ack == 0)) { 2169 /* gross hack to get around certain broken tcp stacks */ 2170 ack = tdata->td_end; 2171 } 2172 2173 maxwin = tdata->td_maxwin; 2174 ackskew = tdata->td_end - ack; 2175 2176 /* 2177 * Strict sequencing only allows in-order delivery. 2178 */ 2179 if ((flags & IS_STRICT) != 0) { 2180 if (seq != fdata->td_end) { 2181 DT2(iss_tcp_struct, tcpdata_t *, fdata, int, seq); 2182 SBUMP(ipf_state_stats.iss_tcp_strict); 2183 fin->fin_flx |= FI_OOW; 2184 return 0; 2185 } 2186 } 2187 2188 #define SEQ_GE(a,b) ((int)((a) - (b)) >= 0) 2189 #define SEQ_GT(a,b) ((int)((a) - (b)) > 0) 2190 inseq = 0; 2191 if ((SEQ_GE(fdata->td_maxend, end)) && 2192 (SEQ_GE(seq, fdata->td_end - maxwin)) && 2193 /* XXX what about big packets */ 2194 #define MAXACKWINDOW 66000 2195 (-ackskew <= (MAXACKWINDOW)) && 2196 ( ackskew <= (MAXACKWINDOW << fdata->td_winscale))) { 2197 inseq = 1; 2198 /* 2199 * Microsoft Windows will send the next packet to the right of the 2200 * window if SACK is in use. 2201 */ 2202 } else if ((seq == fdata->td_maxend) && (ackskew == 0) && 2203 (fdata->td_winflags & TCP_SACK_PERMIT) && 2204 (tdata->td_winflags & TCP_SACK_PERMIT)) { 2205 DT2(iss_sinsack, tcpdata_t *, fdata, int, seq); 2206 SBUMP(ipf_state_stats.iss_winsack); 2207 inseq = 1; 2208 /* 2209 * Sometimes a TCP RST will be generated with only the ACK field 2210 * set to non-zero. 2211 */ 2212 } else if ((seq == 0) && (tcpflags == (TH_RST|TH_ACK)) && 2213 (ackskew >= -1) && (ackskew <= 1)) { 2214 inseq = 1; 2215 } else if (!(flags & IS_TCPFSM)) { 2216 int i; 2217 2218 i = (fin->fin_rev << 1) + fin->fin_out; 2219 2220 #if 0 2221 if (is_pkts[i]0 == 0) { 2222 /* 2223 * Picking up a connection in the middle, the "next" 2224 * packet seen from a direction that is new should be 2225 * accepted, even if it appears out of sequence. 2226 */ 2227 inseq = 1; 2228 } else 2229 #endif 2230 if (!(fdata->td_winflags & 2231 (TCP_WSCALE_SEEN|TCP_WSCALE_FIRST))) { 2232 /* 2233 * No TCPFSM and no window scaling, so make some 2234 * extra guesses. 2235 */ 2236 if ((seq == fdata->td_maxend) && (ackskew == 0)) 2237 inseq = 1; 2238 else if (SEQ_GE(seq + maxwin, fdata->td_end - maxwin)) 2239 inseq = 1; 2240 } 2241 } 2242 2243 /* TRACE(inseq, fdata, tdata, seq, end, ack, ackskew, win, maxwin) */ 2244 2245 if (inseq) { 2246 /* if ackskew < 0 then this should be due to fragmented 2247 * packets. There is no way to know the length of the 2248 * total packet in advance. 2249 * We do know the total length from the fragment cache though. 2250 * Note however that there might be more sessions with 2251 * exactly the same source and destination parameters in the 2252 * state cache (and source and destination is the only stuff 2253 * that is saved in the fragment cache). Note further that 2254 * some TCP connections in the state cache are hashed with 2255 * sport and dport as well which makes it not worthwhile to 2256 * look for them. 2257 * Thus, when ackskew is negative but still seems to belong 2258 * to this session, we bump up the destinations end value. 2259 */ 2260 if (ackskew < 0) 2261 tdata->td_end = ack; 2262 2263 /* update max window seen */ 2264 if (fdata->td_maxwin < win) 2265 fdata->td_maxwin = win; 2266 if (SEQ_GT(end, fdata->td_end)) 2267 fdata->td_end = end; 2268 if (SEQ_GE(ack + win, tdata->td_maxend)) 2269 tdata->td_maxend = ack + win; 2270 return 1; 2271 } 2272 SBUMP(ipf_state_stats.iss_oow); 2273 fin->fin_flx |= FI_OOW; 2274 return 0; 2275 } 2276 2277 2278 /* ------------------------------------------------------------------------ */ 2279 /* Function: ipf_state_clone */ 2280 /* Returns: ipstate_t* - NULL == cloning failed, */ 2281 /* else pointer to new state structure */ 2282 /* Parameters: fin(I) - pointer to packet information */ 2283 /* tcp(I) - pointer to TCP/UDP header */ 2284 /* is(I) - pointer to master state structure */ 2285 /* */ 2286 /* Create a "duplcate" state table entry from the master. */ 2287 /* ------------------------------------------------------------------------ */ 2288 static ipstate_t * 2289 ipf_state_clone(fr_info_t *fin, tcphdr_t *tcp, ipstate_t *is) 2290 { 2291 ipf_main_softc_t *softc = fin->fin_main_soft; 2292 ipf_state_softc_t *softs = softc->ipf_state_soft; 2293 ipstate_t *clone; 2294 u_32_t send; 2295 2296 if (softs->ipf_state_stats.iss_active == softs->ipf_state_max) { 2297 SBUMPD(ipf_state_stats, iss_max); 2298 softs->ipf_state_doflush = 1; 2299 return NULL; 2300 } 2301 KMALLOC(clone, ipstate_t *); 2302 if (clone == NULL) { 2303 SBUMPD(ipf_state_stats, iss_clone_nomem); 2304 return NULL; 2305 } 2306 bcopy((char *)is, (char *)clone, sizeof(*clone)); 2307 2308 MUTEX_NUKE(&clone->is_lock); 2309 /* 2310 * It has not yet been placed on any timeout queue, so make sure 2311 * all of that data is zero'd out. 2312 */ 2313 clone->is_sti.tqe_pnext = NULL; 2314 clone->is_sti.tqe_next = NULL; 2315 clone->is_sti.tqe_ifq = NULL; 2316 clone->is_sti.tqe_parent = clone; 2317 2318 clone->is_die = ONE_DAY + softc->ipf_ticks; 2319 clone->is_state[0] = 0; 2320 clone->is_state[1] = 0; 2321 send = ntohl(tcp->th_seq) + fin->fin_dlen - (TCP_OFF(tcp) << 2) + 2322 ((tcp->th_flags & TH_SYN) ? 1 : 0) + 2323 ((tcp->th_flags & TH_FIN) ? 1 : 0); 2324 2325 if (fin->fin_rev == 1) { 2326 clone->is_dend = send; 2327 clone->is_maxdend = send; 2328 clone->is_send = 0; 2329 clone->is_maxswin = 1; 2330 clone->is_maxdwin = ntohs(tcp->th_win); 2331 if (clone->is_maxdwin == 0) 2332 clone->is_maxdwin = 1; 2333 } else { 2334 clone->is_send = send; 2335 clone->is_maxsend = send; 2336 clone->is_dend = 0; 2337 clone->is_maxdwin = 1; 2338 clone->is_maxswin = ntohs(tcp->th_win); 2339 if (clone->is_maxswin == 0) 2340 clone->is_maxswin = 1; 2341 } 2342 2343 clone->is_flags &= ~SI_CLONE; 2344 clone->is_flags |= SI_CLONED; 2345 if (ipf_state_insert(softc, clone, fin->fin_rev) == -1) { 2346 KFREE(clone); 2347 return NULL; 2348 } 2349 2350 clone->is_ref = 1; 2351 if (clone->is_p == IPPROTO_TCP) { 2352 (void) ipf_tcp_age(&clone->is_sti, fin, softs->ipf_state_tcptq, 2353 clone->is_flags, 2); 2354 } 2355 MUTEX_EXIT(&clone->is_lock); 2356 if (is->is_flags & IS_STATESYNC) 2357 clone->is_sync = ipf_sync_new(softc, SMC_STATE, fin, clone); 2358 DT2(iss_clone, ipstate_t *, is, ipstate_t *, clone); 2359 SBUMP(ipf_state_stats.iss_cloned); 2360 return clone; 2361 } 2362 2363 2364 /* ------------------------------------------------------------------------ */ 2365 /* Function: ipf_matchsrcdst */ 2366 /* Returns: Nil */ 2367 /* Parameters: fin(I) - pointer to packet information */ 2368 /* is(I) - pointer to state structure */ 2369 /* src(I) - pointer to source address */ 2370 /* dst(I) - pointer to destination address */ 2371 /* tcp(I) - pointer to TCP/UDP header */ 2372 /* cmask(I) - mask of FI_* bits to check */ 2373 /* */ 2374 /* Match a state table entry against an IP packet. The logic below is that */ 2375 /* ret gets set to one if the match succeeds, else remains 0. If it is */ 2376 /* still 0 after the test. no match. */ 2377 /* ------------------------------------------------------------------------ */ 2378 static ipstate_t * 2379 ipf_matchsrcdst(fr_info_t *fin, ipstate_t *is, i6addr_t *src, i6addr_t *dst, 2380 tcphdr_t *tcp, u_32_t cmask) 2381 { 2382 ipf_main_softc_t *softc = fin->fin_main_soft; 2383 ipf_state_softc_t *softs = softc->ipf_state_soft; 2384 int ret = 0, rev, out, flags, flx = 0, idx; 2385 u_short sp, dp; 2386 u_32_t cflx; 2387 void *ifp; 2388 2389 /* 2390 * If a connection is about to be deleted, no packets 2391 * are allowed to match it. 2392 */ 2393 if (is->is_sti.tqe_ifq == &softs->ipf_state_deletetq) 2394 return NULL; 2395 2396 rev = IP6_NEQ(&is->is_dst, dst); 2397 ifp = fin->fin_ifp; 2398 out = fin->fin_out; 2399 flags = is->is_flags; 2400 sp = 0; 2401 dp = 0; 2402 2403 if (tcp != NULL) { 2404 sp = htons(fin->fin_sport); 2405 dp = ntohs(fin->fin_dport); 2406 } 2407 if (!rev) { 2408 if (tcp != NULL) { 2409 if (!(flags & SI_W_SPORT) && (sp != is->is_sport)) 2410 rev = 1; 2411 else if (!(flags & SI_W_DPORT) && (dp != is->is_dport)) 2412 rev = 1; 2413 } 2414 } 2415 2416 idx = (out << 1) + rev; 2417 2418 /* 2419 * If the interface for this 'direction' is set, make sure it matches. 2420 * An interface name that is not set matches any, as does a name of *. 2421 */ 2422 if ((is->is_ifp[idx] == ifp) || (is->is_ifp[idx] == NULL && 2423 (*is->is_ifname[idx] == '\0' || *is->is_ifname[idx] == '-' || 2424 *is->is_ifname[idx] == '*'))) 2425 ret = 1; 2426 2427 if (ret == 0) { 2428 DT2(iss_lookup_badifp, fr_info_t *, fin, ipstate_t *, is); 2429 SBUMP(ipf_state_stats.iss_lookup_badifp); 2430 /* TRACE is, out, rev, idx */ 2431 return NULL; 2432 } 2433 ret = 0; 2434 2435 /* 2436 * Match addresses and ports. 2437 */ 2438 if (rev == 0) { 2439 if ((IP6_EQ(&is->is_dst, dst) || (flags & SI_W_DADDR)) && 2440 (IP6_EQ(&is->is_src, src) || (flags & SI_W_SADDR))) { 2441 if (tcp) { 2442 if ((sp == is->is_sport || flags & SI_W_SPORT) 2443 && 2444 (dp == is->is_dport || flags & SI_W_DPORT)) 2445 ret = 1; 2446 } else { 2447 ret = 1; 2448 } 2449 } 2450 } else { 2451 if ((IP6_EQ(&is->is_dst, src) || (flags & SI_W_DADDR)) && 2452 (IP6_EQ(&is->is_src, dst) || (flags & SI_W_SADDR))) { 2453 if (tcp) { 2454 if ((dp == is->is_sport || flags & SI_W_SPORT) 2455 && 2456 (sp == is->is_dport || flags & SI_W_DPORT)) 2457 ret = 1; 2458 } else { 2459 ret = 1; 2460 } 2461 } 2462 } 2463 2464 if (ret == 0) { 2465 SBUMP(ipf_state_stats.iss_lookup_badport); 2466 DT2(iss_lookup_badport, fr_info_t *, fin, ipstate_t *, is); 2467 /* TRACE rev, is, sp, dp, src, dst */ 2468 return NULL; 2469 } 2470 2471 /* 2472 * Whether or not this should be here, is questionable, but the aim 2473 * is to get this out of the main line. 2474 */ 2475 if (tcp == NULL) 2476 flags = is->is_flags & ~(SI_WILDP|SI_NEWFR|SI_CLONE|SI_CLONED); 2477 2478 /* 2479 * Only one of the source or destination address can be flaged as a 2480 * wildcard. Fill in the missing address, if set. 2481 * For IPv6, if the address being copied in is multicast, then 2482 * don't reset the wild flag - multicast causes it to be set in the 2483 * first place! 2484 */ 2485 if ((flags & (SI_W_SADDR|SI_W_DADDR))) { 2486 fr_ip_t *fi = &fin->fin_fi; 2487 2488 if ((flags & SI_W_SADDR) != 0) { 2489 if (rev == 0) { 2490 is->is_src = fi->fi_src; 2491 is->is_flags &= ~SI_W_SADDR; 2492 } else { 2493 if (!(fin->fin_flx & (FI_MULTICAST|FI_MBCAST))){ 2494 is->is_src = fi->fi_dst; 2495 is->is_flags &= ~SI_W_SADDR; 2496 } 2497 } 2498 } else if ((flags & SI_W_DADDR) != 0) { 2499 if (rev == 0) { 2500 if (!(fin->fin_flx & (FI_MULTICAST|FI_MBCAST))){ 2501 is->is_dst = fi->fi_dst; 2502 is->is_flags &= ~SI_W_DADDR; 2503 } 2504 } else { 2505 is->is_dst = fi->fi_src; 2506 is->is_flags &= ~SI_W_DADDR; 2507 } 2508 } 2509 if ((is->is_flags & (SI_WILDA|SI_WILDP)) == 0) { 2510 ATOMIC_DECL(softs->ipf_state_stats.iss_wild); 2511 } 2512 } 2513 2514 flx = fin->fin_flx & cmask; 2515 cflx = is->is_flx[out][rev]; 2516 2517 /* 2518 * Match up any flags set from IP options. 2519 */ 2520 if ((cflx && (flx != (cflx & cmask))) || 2521 ((fin->fin_optmsk & is->is_optmsk[rev]) != is->is_opt[rev]) || 2522 ((fin->fin_secmsk & is->is_secmsk) != is->is_sec) || 2523 ((fin->fin_auth & is->is_authmsk) != is->is_auth)) { 2524 SBUMPD(ipf_state_stats, iss_miss_mask); 2525 return NULL; 2526 } 2527 2528 if ((fin->fin_flx & FI_IGNORE) != 0) { 2529 fin->fin_rev = rev; 2530 return is; 2531 } 2532 2533 /* 2534 * Only one of the source or destination port can be flagged as a 2535 * wildcard. When filling it in, fill in a copy of the matched entry 2536 * if it has the cloning flag set. 2537 */ 2538 if ((flags & (SI_W_SPORT|SI_W_DPORT))) { 2539 if ((flags & SI_CLONE) != 0) { 2540 ipstate_t *clone; 2541 2542 clone = ipf_state_clone(fin, tcp, is); 2543 if (clone == NULL) 2544 return NULL; 2545 is = clone; 2546 } else { 2547 ATOMIC_DECL(softs->ipf_state_stats.iss_wild); 2548 } 2549 2550 if ((flags & SI_W_SPORT) != 0) { 2551 if (rev == 0) { 2552 is->is_sport = sp; 2553 is->is_send = ntohl(tcp->th_seq); 2554 } else { 2555 is->is_sport = dp; 2556 is->is_send = ntohl(tcp->th_ack); 2557 } 2558 is->is_maxsend = is->is_send + 1; 2559 } else if ((flags & SI_W_DPORT) != 0) { 2560 if (rev == 0) { 2561 is->is_dport = dp; 2562 is->is_dend = ntohl(tcp->th_ack); 2563 } else { 2564 is->is_dport = sp; 2565 is->is_dend = ntohl(tcp->th_seq); 2566 } 2567 is->is_maxdend = is->is_dend + 1; 2568 } 2569 is->is_flags &= ~(SI_W_SPORT|SI_W_DPORT); 2570 if ((flags & SI_CLONED) && softs->ipf_state_logging) 2571 ipf_state_log(softc, is, ISL_CLONE); 2572 } 2573 2574 ret = -1; 2575 2576 if (is->is_flx[out][rev] == 0) { 2577 is->is_flx[out][rev] = flx; 2578 if (rev == 1 && is->is_optmsk[1] == 0) { 2579 is->is_opt[1] = fin->fin_optmsk; 2580 is->is_optmsk[1] = 0xffffffff; 2581 if (is->is_v == 6) { 2582 is->is_opt[1] &= ~0x8; 2583 is->is_optmsk[1] &= ~0x8; 2584 } 2585 } 2586 } 2587 2588 /* 2589 * Check if the interface name for this "direction" is set and if not, 2590 * fill it in. 2591 */ 2592 if (is->is_ifp[idx] == NULL && 2593 (*is->is_ifname[idx] == '\0' || *is->is_ifname[idx] == '*')) { 2594 is->is_ifp[idx] = ifp; 2595 COPYIFNAME(fin->fin_v, ifp, is->is_ifname[idx]); 2596 } 2597 fin->fin_rev = rev; 2598 return is; 2599 } 2600 2601 2602 /* ------------------------------------------------------------------------ */ 2603 /* Function: ipf_checkicmpmatchingstate */ 2604 /* Returns: Nil */ 2605 /* Parameters: fin(I) - pointer to packet information */ 2606 /* */ 2607 /* If we've got an ICMP error message, using the information stored in the */ 2608 /* ICMP packet, look for a matching state table entry. */ 2609 /* */ 2610 /* If we return NULL then no lock on ipf_state is held. */ 2611 /* If we return non-null then a read-lock on ipf_state is held. */ 2612 /* ------------------------------------------------------------------------ */ 2613 static ipstate_t * 2614 ipf_checkicmpmatchingstate(fr_info_t *fin) 2615 { 2616 ipf_main_softc_t *softc = fin->fin_main_soft; 2617 ipf_state_softc_t *softs = softc->ipf_state_soft; 2618 ipstate_t *is, **isp; 2619 i6addr_t dst, src; 2620 struct icmp *ic; 2621 u_short savelen; 2622 icmphdr_t *icmp; 2623 fr_info_t ofin; 2624 tcphdr_t *tcp; 2625 int type, len; 2626 u_char pr; 2627 ip_t *oip; 2628 u_int hv; 2629 2630 /* 2631 * Does it at least have the return (basic) IP header ? 2632 * Is it an actual recognised ICMP error type? 2633 * Only a basic IP header (no options) should be with 2634 * an ICMP error header. 2635 */ 2636 if ((fin->fin_v != 4) || (fin->fin_hlen != sizeof(ip_t)) || 2637 (fin->fin_plen < ICMPERR_MINPKTLEN) || 2638 !(fin->fin_flx & FI_ICMPERR)) { 2639 SBUMPD(ipf_state_stats, iss_icmp_bad); 2640 return NULL; 2641 } 2642 ic = fin->fin_dp; 2643 type = ic->icmp_type; 2644 2645 oip = (ip_t *)((char *)ic + ICMPERR_ICMPHLEN); 2646 /* 2647 * Check if the at least the old IP header (with options) and 2648 * 8 bytes of payload is present. 2649 */ 2650 if (fin->fin_plen < ICMPERR_MAXPKTLEN + ((IP_HL(oip) - 5) << 2)) { 2651 SBUMPDX(ipf_state_stats, iss_icmp_short, iss_icmp_short_1); 2652 return NULL; 2653 } 2654 2655 /* 2656 * Sanity Checks. 2657 */ 2658 len = fin->fin_dlen - ICMPERR_ICMPHLEN; 2659 if ((len <= 0) || ((IP_HL(oip) << 2) > len)) { 2660 DT2(iss_icmp_len, fr_info_t *, fin, struct ip*, oip); 2661 SBUMPDX(ipf_state_stats, iss_icmp_short, iss_icmp_short_1); 2662 return NULL; 2663 } 2664 2665 /* 2666 * Is the buffer big enough for all of it ? It's the size of the IP 2667 * header claimed in the encapsulated part which is of concern. It 2668 * may be too big to be in this buffer but not so big that it's 2669 * outside the ICMP packet, leading to TCP deref's causing problems. 2670 * This is possible because we don't know how big oip_hl is when we 2671 * do the pullup early in ipf_check() and thus can't guarantee it is 2672 * all here now. 2673 */ 2674 #ifdef _KERNEL 2675 { 2676 mb_t *m; 2677 2678 m = fin->fin_m; 2679 # if defined(MENTAT) 2680 if ((char *)oip + len > (char *)m->b_wptr) { 2681 SBUMPDX(ipf_state_stats, iss_icmp_short, iss_icmp_short_2); 2682 return NULL; 2683 } 2684 # else 2685 if ((char *)oip + len > (char *)fin->fin_ip + m->m_len) { 2686 SBUMPDX(ipf_state_stats, iss_icmp_short, iss_icmp_short_3); 2687 return NULL; 2688 } 2689 # endif 2690 } 2691 #endif 2692 2693 bcopy((char *)fin, (char *)&ofin, sizeof(*fin)); 2694 2695 /* 2696 * in the IPv4 case we must zero the i6addr union otherwise 2697 * the IP6_EQ and IP6_NEQ macros produce the wrong results because 2698 * of the 'junk' in the unused part of the union 2699 */ 2700 bzero((char *)&src, sizeof(src)); 2701 bzero((char *)&dst, sizeof(dst)); 2702 2703 /* 2704 * we make an fin entry to be able to feed it to 2705 * matchsrcdst note that not all fields are encessary 2706 * but this is the cleanest way. Note further we fill 2707 * in fin_mp such that if someone uses it we'll get 2708 * a kernel panic. ipf_matchsrcdst does not use this. 2709 * 2710 * watch out here, as ip is in host order and oip in network 2711 * order. Any change we make must be undone afterwards, like 2712 * oip->ip_len. 2713 */ 2714 savelen = oip->ip_len; 2715 oip->ip_len = htons(len); 2716 2717 ofin.fin_flx = FI_NOCKSUM; 2718 ofin.fin_v = 4; 2719 ofin.fin_ip = oip; 2720 ofin.fin_m = NULL; /* if dereferenced, panic XXX */ 2721 ofin.fin_mp = NULL; /* if dereferenced, panic XXX */ 2722 (void) ipf_makefrip(IP_HL(oip) << 2, oip, &ofin); 2723 ofin.fin_ifp = fin->fin_ifp; 2724 ofin.fin_out = !fin->fin_out; 2725 2726 hv = (pr = oip->ip_p); 2727 src.in4 = oip->ip_src; 2728 hv += src.in4.s_addr; 2729 dst.in4 = oip->ip_dst; 2730 hv += dst.in4.s_addr; 2731 2732 /* 2733 * Reset the short and bad flag here because in ipf_matchsrcdst() 2734 * the flags for the current packet (fin_flx) are compared against 2735 * those for the existing session. 2736 */ 2737 ofin.fin_flx &= ~(FI_BAD|FI_SHORT); 2738 2739 /* 2740 * Put old values of ip_len back as we don't know 2741 * if we have to forward the packet or process it again. 2742 */ 2743 oip->ip_len = savelen; 2744 2745 switch (oip->ip_p) 2746 { 2747 case IPPROTO_ICMP : 2748 /* 2749 * an ICMP error can only be generated as a result of an 2750 * ICMP query, not as the response on an ICMP error 2751 * 2752 * XXX theoretically ICMP_ECHOREP and the other reply's are 2753 * ICMP query's as well, but adding them here seems strange XXX 2754 */ 2755 if ((ofin.fin_flx & FI_ICMPERR) != 0) { 2756 DT1(iss_icmp_icmperr, fr_info_t *, &ofin); 2757 SBUMP(ipf_state_stats.iss_icmp_icmperr); 2758 return NULL; 2759 } 2760 2761 /* 2762 * perform a lookup of the ICMP packet in the state table 2763 */ 2764 icmp = (icmphdr_t *)((char *)oip + (IP_HL(oip) << 2)); 2765 hv += icmp->icmp_id; 2766 hv = DOUBLE_HASH(hv); 2767 2768 READ_ENTER(&softc->ipf_state); 2769 for (isp = &softs->ipf_state_table[hv]; 2770 ((is = *isp) != NULL); ) { 2771 isp = &is->is_hnext; 2772 if ((is->is_p != pr) || (is->is_v != 4)) 2773 continue; 2774 if (is->is_pass & FR_NOICMPERR) 2775 continue; 2776 2777 is = ipf_matchsrcdst(&ofin, is, &src, &dst, 2778 NULL, FI_ICMPCMP); 2779 if ((is != NULL) && !ipf_allowstateicmp(fin, is, &src)) 2780 return is; 2781 } 2782 RWLOCK_EXIT(&softc->ipf_state); 2783 SBUMPDX(ipf_state_stats, iss_icmp_miss, iss_icmp_miss_1); 2784 return NULL; 2785 case IPPROTO_TCP : 2786 case IPPROTO_UDP : 2787 break; 2788 default : 2789 SBUMPDX(ipf_state_stats, iss_icmp_miss, iss_icmp_miss_2); 2790 return NULL; 2791 } 2792 2793 tcp = (tcphdr_t *)((char *)oip + (IP_HL(oip) << 2)); 2794 2795 hv += tcp->th_dport;; 2796 hv += tcp->th_sport;; 2797 hv = DOUBLE_HASH(hv); 2798 2799 READ_ENTER(&softc->ipf_state); 2800 for (isp = &softs->ipf_state_table[hv]; ((is = *isp) != NULL); ) { 2801 isp = &is->is_hnext; 2802 /* 2803 * Only allow this icmp though if the 2804 * encapsulated packet was allowed through the 2805 * other way around. Note that the minimal amount 2806 * of info present does not allow for checking against 2807 * tcp internals such as seq and ack numbers. Only the 2808 * ports are known to be present and can be even if the 2809 * short flag is set. 2810 */ 2811 if ((is->is_p == pr) && (is->is_v == 4) && 2812 (is = ipf_matchsrcdst(&ofin, is, &src, &dst, 2813 tcp, FI_ICMPCMP))) { 2814 if (ipf_allowstateicmp(fin, is, &src) == 0) 2815 return is; 2816 } 2817 } 2818 RWLOCK_EXIT(&softc->ipf_state); 2819 SBUMPDX(ipf_state_stats, iss_icmp_miss, iss_icmp_miss_3); 2820 return NULL; 2821 } 2822 2823 2824 /* ------------------------------------------------------------------------ */ 2825 /* Function: ipf_allowstateicmp */ 2826 /* Returns: int - 1 = packet denied, 0 = packet allowed */ 2827 /* Parameters: fin(I) - pointer to packet information */ 2828 /* is(I) - pointer to state table entry */ 2829 /* src(I) - source address to check permission for */ 2830 /* */ 2831 /* For an ICMP packet that has so far matched a state table entry, check if */ 2832 /* there are any further refinements that might mean we want to block this */ 2833 /* packet. This code isn't specific to either IPv4 or IPv6. */ 2834 /* ------------------------------------------------------------------------ */ 2835 static int 2836 ipf_allowstateicmp(fr_info_t *fin, ipstate_t *is, i6addr_t *src) 2837 { 2838 ipf_main_softc_t *softc = fin->fin_main_soft; 2839 ipf_state_softc_t *softs = softc->ipf_state_soft; 2840 frentry_t *savefr; 2841 frentry_t *fr; 2842 u_32_t ipass; 2843 int backward; 2844 int oi; 2845 int i; 2846 2847 fr = is->is_rule; 2848 if (fr != NULL && fr->fr_icmpgrp != NULL) { 2849 savefr = fin->fin_fr; 2850 fin->fin_fr = fr->fr_icmpgrp->fg_start; 2851 2852 ipass = ipf_scanlist(fin, softc->ipf_pass); 2853 fin->fin_fr = savefr; 2854 if (FR_ISBLOCK(ipass)) { 2855 SBUMPD(ipf_state_stats, iss_icmp_headblock); 2856 return 1; 2857 } 2858 } 2859 2860 /* 2861 * i : the index of this packet (the icmp unreachable) 2862 * oi : the index of the original packet found in the 2863 * icmp header (i.e. the packet causing this icmp) 2864 * backward : original packet was backward compared to 2865 * the state 2866 */ 2867 backward = IP6_NEQ(&is->is_src, src); 2868 fin->fin_rev = !backward; 2869 i = (!backward << 1) + fin->fin_out; 2870 oi = (backward << 1) + !fin->fin_out; 2871 2872 if (is->is_pass & FR_NOICMPERR) { 2873 SBUMPD(ipf_state_stats, iss_icmp_banned); 2874 return 1; 2875 } 2876 if (is->is_icmppkts[i] > is->is_pkts[oi]) { 2877 SBUMPD(ipf_state_stats, iss_icmp_toomany); 2878 return 1; 2879 } 2880 2881 DT2(iss_icmp_hits, fr_info_t *, fin, ipstate_t *, is); 2882 SBUMP(ipf_state_stats.iss_icmp_hits); 2883 is->is_icmppkts[i]++; 2884 2885 /* 2886 * we deliberately do not touch the timeouts 2887 * for the accompanying state table entry. 2888 * It remains to be seen if that is correct. XXX 2889 */ 2890 return 0; 2891 } 2892 2893 2894 /* ------------------------------------------------------------------------ */ 2895 /* Function: ipf_ipsmove */ 2896 /* Returns: Nil */ 2897 /* Parameters: is(I) - pointer to state table entry */ 2898 /* hv(I) - new hash value for state table entry */ 2899 /* Write Locks: ipf_state */ 2900 /* */ 2901 /* Move a state entry from one position in the hash table to another. */ 2902 /* ------------------------------------------------------------------------ */ 2903 static void 2904 ipf_ipsmove(ipf_state_softc_t *softs, ipstate_t *is, u_int hv) 2905 { 2906 ipstate_t **isp; 2907 u_int hvm; 2908 2909 hvm = is->is_hv; 2910 2911 /* TRACE is, is_hv, hvm */ 2912 2913 /* 2914 * Remove the hash from the old location... 2915 */ 2916 isp = is->is_phnext; 2917 if (is->is_hnext) 2918 is->is_hnext->is_phnext = isp; 2919 *isp = is->is_hnext; 2920 if (softs->ipf_state_table[hvm] == NULL) 2921 softs->ipf_state_stats.iss_inuse--; 2922 softs->ipf_state_stats.iss_bucketlen[hvm]--; 2923 2924 /* 2925 * ...and put the hash in the new one. 2926 */ 2927 hvm = DOUBLE_HASH(hv); 2928 is->is_hv = hvm; 2929 2930 /* TRACE is, hv, is_hv, hvm */ 2931 2932 isp = &softs->ipf_state_table[hvm]; 2933 if (*isp) 2934 (*isp)->is_phnext = &is->is_hnext; 2935 else 2936 softs->ipf_state_stats.iss_inuse++; 2937 softs->ipf_state_stats.iss_bucketlen[hvm]++; 2938 is->is_phnext = isp; 2939 is->is_hnext = *isp; 2940 *isp = is; 2941 } 2942 2943 2944 /* ------------------------------------------------------------------------ */ 2945 /* Function: ipf_state_lookup */ 2946 /* Returns: ipstate_t* - NULL == no matching state found, */ 2947 /* else pointer to state information is returned */ 2948 /* Parameters: fin(I) - pointer to packet information */ 2949 /* tcp(I) - pointer to TCP/UDP header. */ 2950 /* ifqp(O) - pointer for storing tailq timeout */ 2951 /* */ 2952 /* Search the state table for a matching entry to the packet described by */ 2953 /* the contents of *fin. For certain protocols, when a match is found the */ 2954 /* timeout queue is also selected and stored in ifpq if it is non-NULL. */ 2955 /* */ 2956 /* If we return NULL then no lock on ipf_state is held. */ 2957 /* If we return non-null then a read-lock on ipf_state is held. */ 2958 /* ------------------------------------------------------------------------ */ 2959 ipstate_t * 2960 ipf_state_lookup(fr_info_t *fin, tcphdr_t *tcp, ipftq_t **ifqp) 2961 { 2962 ipf_main_softc_t *softc = fin->fin_main_soft; 2963 ipf_state_softc_t *softs = softc->ipf_state_soft; 2964 u_int hv, hvm, pr, v, tryagain; 2965 ipstate_t *is, **isp; 2966 u_short dport, sport; 2967 i6addr_t src, dst; 2968 struct icmp *ic; 2969 ipftq_t *ifq; 2970 int oow; 2971 2972 is = NULL; 2973 ifq = NULL; 2974 tcp = fin->fin_dp; 2975 ic = (struct icmp *)tcp; 2976 hv = (pr = fin->fin_fi.fi_p); 2977 src = fin->fin_fi.fi_src; 2978 dst = fin->fin_fi.fi_dst; 2979 hv += src.in4.s_addr; 2980 hv += dst.in4.s_addr; 2981 2982 v = fin->fin_fi.fi_v; 2983 #ifdef USE_INET6 2984 if (v == 6) { 2985 hv += fin->fin_fi.fi_src.i6[1]; 2986 hv += fin->fin_fi.fi_src.i6[2]; 2987 hv += fin->fin_fi.fi_src.i6[3]; 2988 2989 if ((fin->fin_p == IPPROTO_ICMPV6) && 2990 IN6_IS_ADDR_MULTICAST(&fin->fin_fi.fi_dst.in6)) { 2991 hv -= dst.in4.s_addr; 2992 } else { 2993 hv += fin->fin_fi.fi_dst.i6[1]; 2994 hv += fin->fin_fi.fi_dst.i6[2]; 2995 hv += fin->fin_fi.fi_dst.i6[3]; 2996 } 2997 } 2998 #endif 2999 if ((v == 4) && 3000 (fin->fin_flx & (FI_MULTICAST|FI_BROADCAST|FI_MBCAST))) { 3001 if (fin->fin_out == 0) { 3002 hv -= src.in4.s_addr; 3003 } else { 3004 hv -= dst.in4.s_addr; 3005 } 3006 } 3007 3008 /* TRACE fin_saddr, fin_daddr, hv */ 3009 3010 /* 3011 * Search the hash table for matching packet header info. 3012 */ 3013 switch (pr) 3014 { 3015 #ifdef USE_INET6 3016 case IPPROTO_ICMPV6 : 3017 tryagain = 0; 3018 if (v == 6) { 3019 if ((ic->icmp_type == ICMP6_ECHO_REQUEST) || 3020 (ic->icmp_type == ICMP6_ECHO_REPLY)) { 3021 hv += ic->icmp_id; 3022 } 3023 } 3024 READ_ENTER(&softc->ipf_state); 3025 icmp6again: 3026 hvm = DOUBLE_HASH(hv); 3027 for (isp = &softs->ipf_state_table[hvm]; 3028 ((is = *isp) != NULL); ) { 3029 isp = &is->is_hnext; 3030 if ((is->is_p != pr) || (is->is_v != v)) 3031 continue; 3032 is = ipf_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP); 3033 if (is != NULL && 3034 ipf_matchicmpqueryreply(v, &is->is_icmp, 3035 ic, fin->fin_rev)) { 3036 if (fin->fin_rev) 3037 ifq = &softs->ipf_state_icmpacktq; 3038 else 3039 ifq = &softs->ipf_state_icmptq; 3040 break; 3041 } 3042 } 3043 3044 if (is != NULL) { 3045 if ((tryagain != 0) && !(is->is_flags & SI_W_DADDR)) { 3046 hv += fin->fin_fi.fi_src.i6[0]; 3047 hv += fin->fin_fi.fi_src.i6[1]; 3048 hv += fin->fin_fi.fi_src.i6[2]; 3049 hv += fin->fin_fi.fi_src.i6[3]; 3050 ipf_ipsmove(softs, is, hv); 3051 MUTEX_DOWNGRADE(&softc->ipf_state); 3052 } 3053 break; 3054 } 3055 RWLOCK_EXIT(&softc->ipf_state); 3056 3057 /* 3058 * No matching icmp state entry. Perhaps this is a 3059 * response to another state entry. 3060 * 3061 * XXX With some ICMP6 packets, the "other" address is already 3062 * in the packet, after the ICMP6 header, and this could be 3063 * used in place of the multicast address. However, taking 3064 * advantage of this requires some significant code changes 3065 * to handle the specific types where that is the case. 3066 */ 3067 if ((softs->ipf_state_stats.iss_wild != 0) && 3068 ((fin->fin_flx & FI_NOWILD) == 0) && 3069 (v == 6) && (tryagain == 0)) { 3070 hv -= fin->fin_fi.fi_src.i6[0]; 3071 hv -= fin->fin_fi.fi_src.i6[1]; 3072 hv -= fin->fin_fi.fi_src.i6[2]; 3073 hv -= fin->fin_fi.fi_src.i6[3]; 3074 tryagain = 1; 3075 WRITE_ENTER(&softc->ipf_state); 3076 goto icmp6again; 3077 } 3078 3079 is = ipf_checkicmp6matchingstate(fin); 3080 if (is != NULL) 3081 return is; 3082 break; 3083 #endif 3084 3085 case IPPROTO_ICMP : 3086 if (v == 4) { 3087 hv += ic->icmp_id; 3088 } 3089 hv = DOUBLE_HASH(hv); 3090 READ_ENTER(&softc->ipf_state); 3091 for (isp = &softs->ipf_state_table[hv]; 3092 ((is = *isp) != NULL); ) { 3093 isp = &is->is_hnext; 3094 if ((is->is_p != pr) || (is->is_v != v)) 3095 continue; 3096 is = ipf_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP); 3097 if ((is != NULL) && 3098 (ic->icmp_id == is->is_icmp.ici_id) && 3099 ipf_matchicmpqueryreply(v, &is->is_icmp, 3100 ic, fin->fin_rev)) { 3101 if (fin->fin_rev) 3102 ifq = &softs->ipf_state_icmpacktq; 3103 else 3104 ifq = &softs->ipf_state_icmptq; 3105 break; 3106 } 3107 } 3108 if (is == NULL) { 3109 RWLOCK_EXIT(&softc->ipf_state); 3110 } 3111 break; 3112 3113 case IPPROTO_TCP : 3114 case IPPROTO_UDP : 3115 ifqp = NULL; 3116 sport = htons(fin->fin_data[0]); 3117 hv += sport; 3118 dport = htons(fin->fin_data[1]); 3119 hv += dport; 3120 oow = 0; 3121 tryagain = 0; 3122 READ_ENTER(&softc->ipf_state); 3123 retry_tcpudp: 3124 hvm = DOUBLE_HASH(hv); 3125 3126 /* TRACE hv, hvm */ 3127 3128 for (isp = &softs->ipf_state_table[hvm]; 3129 ((is = *isp) != NULL); ) { 3130 isp = &is->is_hnext; 3131 if ((is->is_p != pr) || (is->is_v != v)) 3132 continue; 3133 fin->fin_flx &= ~FI_OOW; 3134 is = ipf_matchsrcdst(fin, is, &src, &dst, tcp, FI_CMP); 3135 if (is != NULL) { 3136 if (pr == IPPROTO_TCP) { 3137 if (!ipf_state_tcp(softc, softs, fin, 3138 tcp, is)) { 3139 oow |= fin->fin_flx & FI_OOW; 3140 continue; 3141 } 3142 } 3143 break; 3144 } 3145 } 3146 if (is != NULL) { 3147 if (tryagain && 3148 !(is->is_flags & (SI_CLONE|SI_WILDP|SI_WILDA))) { 3149 hv += dport; 3150 hv += sport; 3151 ipf_ipsmove(softs, is, hv); 3152 MUTEX_DOWNGRADE(&softc->ipf_state); 3153 } 3154 break; 3155 } 3156 RWLOCK_EXIT(&softc->ipf_state); 3157 3158 if ((softs->ipf_state_stats.iss_wild != 0) && 3159 ((fin->fin_flx & FI_NOWILD) == 0)) { 3160 if (tryagain == 0) { 3161 hv -= dport; 3162 hv -= sport; 3163 } else if (tryagain == 1) { 3164 hv = fin->fin_fi.fi_p; 3165 /* 3166 * If we try to pretend this is a reply to a 3167 * multicast/broadcast packet then we need to 3168 * exclude part of the address from the hash 3169 * calculation. 3170 */ 3171 if (fin->fin_out == 0) { 3172 hv += src.in4.s_addr; 3173 } else { 3174 hv += dst.in4.s_addr; 3175 } 3176 hv += dport; 3177 hv += sport; 3178 } 3179 tryagain++; 3180 if (tryagain <= 2) { 3181 WRITE_ENTER(&softc->ipf_state); 3182 goto retry_tcpudp; 3183 } 3184 } 3185 fin->fin_flx |= oow; 3186 break; 3187 3188 #if 0 3189 case IPPROTO_GRE : 3190 gre = fin->fin_dp; 3191 if (GRE_REV(gre->gr_flags) == 1) { 3192 hv += gre->gr_call; 3193 } 3194 /* FALLTHROUGH */ 3195 #endif 3196 default : 3197 ifqp = NULL; 3198 hvm = DOUBLE_HASH(hv); 3199 READ_ENTER(&softc->ipf_state); 3200 for (isp = &softs->ipf_state_table[hvm]; 3201 ((is = *isp) != NULL); ) { 3202 isp = &is->is_hnext; 3203 if ((is->is_p != pr) || (is->is_v != v)) 3204 continue; 3205 is = ipf_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP); 3206 if (is != NULL) { 3207 ifq = &softs->ipf_state_iptq; 3208 break; 3209 } 3210 } 3211 if (is == NULL) { 3212 RWLOCK_EXIT(&softc->ipf_state); 3213 } 3214 break; 3215 } 3216 3217 if (is != NULL) { 3218 if (((is->is_sti.tqe_flags & TQE_RULEBASED) != 0) && 3219 (is->is_tqehead[fin->fin_rev] != NULL)) 3220 ifq = is->is_tqehead[fin->fin_rev]; 3221 if (ifq != NULL && ifqp != NULL) 3222 *ifqp = ifq; 3223 } else { 3224 SBUMP(ipf_state_stats.iss_lookup_miss); 3225 } 3226 return is; 3227 } 3228 3229 3230 /* ------------------------------------------------------------------------ */ 3231 /* Function: ipf_state_check */ 3232 /* Returns: frentry_t* - NULL == search failed, */ 3233 /* else pointer to rule for matching state */ 3234 /* Parameters: fin(I) - pointer to packet information */ 3235 /* passp(I) - pointer to filtering result flags */ 3236 /* */ 3237 /* Check if a packet is associated with an entry in the state table. */ 3238 /* ------------------------------------------------------------------------ */ 3239 frentry_t * 3240 ipf_state_check(fr_info_t *fin, u_32_t *passp) 3241 { 3242 ipf_main_softc_t *softc = fin->fin_main_soft; 3243 ipf_state_softc_t *softs = softc->ipf_state_soft; 3244 ipftqent_t *tqe; 3245 ipstate_t *is; 3246 frentry_t *fr; 3247 tcphdr_t *tcp; 3248 ipftq_t *ifq; 3249 u_int pass; 3250 int inout; 3251 3252 if (softs->ipf_state_lock || (softs->ipf_state_list == NULL)) 3253 return NULL; 3254 3255 if (fin->fin_flx & (FI_SHORT|FI_FRAGBODY|FI_BAD)) { 3256 SBUMPD(ipf_state_stats, iss_check_bad); 3257 return NULL; 3258 } 3259 3260 if ((fin->fin_flx & FI_TCPUDP) || 3261 (fin->fin_fi.fi_p == IPPROTO_ICMP) 3262 #ifdef USE_INET6 3263 || (fin->fin_fi.fi_p == IPPROTO_ICMPV6) 3264 #endif 3265 ) 3266 tcp = fin->fin_dp; 3267 else 3268 tcp = NULL; 3269 3270 ifq = NULL; 3271 /* 3272 * Search the hash table for matching packet header info. 3273 */ 3274 is = ipf_state_lookup(fin, tcp, &ifq); 3275 3276 switch (fin->fin_p) 3277 { 3278 #ifdef USE_INET6 3279 case IPPROTO_ICMPV6 : 3280 if (is != NULL) 3281 break; 3282 if (fin->fin_v == 6) { 3283 is = ipf_checkicmp6matchingstate(fin); 3284 } 3285 break; 3286 #endif 3287 case IPPROTO_ICMP : 3288 if (is != NULL) 3289 break; 3290 /* 3291 * No matching icmp state entry. Perhaps this is a 3292 * response to another state entry. 3293 */ 3294 is = ipf_checkicmpmatchingstate(fin); 3295 break; 3296 3297 case IPPROTO_TCP : 3298 if (is == NULL) 3299 break; 3300 3301 if (is->is_pass & FR_NEWISN) { 3302 if (fin->fin_out == 0) 3303 ipf_fixinisn(fin, is); 3304 else if (fin->fin_out == 1) 3305 ipf_fixoutisn(fin, is); 3306 } 3307 break; 3308 default : 3309 if (fin->fin_rev) 3310 ifq = &softs->ipf_state_udpacktq; 3311 else 3312 ifq = &softs->ipf_state_udptq; 3313 break; 3314 } 3315 if (is == NULL) { 3316 SBUMP(ipf_state_stats.iss_check_miss); 3317 return NULL; 3318 } 3319 3320 fr = is->is_rule; 3321 if (fr != NULL) { 3322 if ((fin->fin_out == 0) && (fr->fr_nattag.ipt_num[0] != 0)) { 3323 if (fin->fin_nattag == NULL) { 3324 RWLOCK_EXIT(&softc->ipf_state); 3325 SBUMPD(ipf_state_stats, iss_check_notag); 3326 return NULL; 3327 } 3328 if (ipf_matchtag(&fr->fr_nattag, fin->fin_nattag)!=0) { 3329 RWLOCK_EXIT(&softc->ipf_state); 3330 SBUMPD(ipf_state_stats, iss_check_nattag); 3331 return NULL; 3332 } 3333 } 3334 (void) strncpy(fin->fin_group, FR_NAME(fr, fr_group), 3335 FR_GROUPLEN); 3336 fin->fin_icode = fr->fr_icode; 3337 } 3338 3339 fin->fin_rule = is->is_rulen; 3340 fin->fin_fr = fr; 3341 3342 /* 3343 * If this packet is a fragment and the rule says to track fragments, 3344 * then create a new fragment cache entry. 3345 */ 3346 if ((fin->fin_flx & FI_FRAG) && FR_ISPASS(is->is_pass)) 3347 (void) ipf_frag_new(softc, fin, is->is_pass); 3348 3349 /* 3350 * For TCP packets, ifq == NULL. For all others, check if this new 3351 * queue is different to the last one it was on and move it if so. 3352 */ 3353 tqe = &is->is_sti; 3354 if ((tqe->tqe_flags & TQE_RULEBASED) != 0) 3355 ifq = is->is_tqehead[fin->fin_rev]; 3356 3357 MUTEX_ENTER(&is->is_lock); 3358 3359 if (ifq != NULL) 3360 ipf_movequeue(softc->ipf_ticks, tqe, tqe->tqe_ifq, ifq); 3361 3362 inout = (fin->fin_rev << 1) + fin->fin_out; 3363 is->is_pkts[inout]++; 3364 is->is_bytes[inout] += fin->fin_plen; 3365 fin->fin_pktnum = is->is_pkts[inout] + is->is_icmppkts[inout]; 3366 3367 MUTEX_EXIT(&is->is_lock); 3368 3369 pass = is->is_pass; 3370 3371 if (is->is_flags & IS_STATESYNC) 3372 ipf_sync_update(softc, SMC_STATE, fin, is->is_sync); 3373 3374 RWLOCK_EXIT(&softc->ipf_state); 3375 3376 SBUMP(ipf_state_stats.iss_hits); 3377 3378 fin->fin_dif = &is->is_dif; 3379 fin->fin_tif = &is->is_tifs[fin->fin_rev]; 3380 fin->fin_flx |= FI_STATE; 3381 if ((pass & FR_LOGFIRST) != 0) 3382 pass &= ~(FR_LOGFIRST|FR_LOG); 3383 *passp = pass; 3384 return fr; 3385 } 3386 3387 3388 /* ------------------------------------------------------------------------ */ 3389 /* Function: ipf_fixoutisn */ 3390 /* Returns: Nil */ 3391 /* Parameters: fin(I) - pointer to packet information */ 3392 /* is(I) - pointer to master state structure */ 3393 /* */ 3394 /* Called only for outbound packets, adjusts the sequence number and the */ 3395 /* TCP checksum to match that change. */ 3396 /* ------------------------------------------------------------------------ */ 3397 static void 3398 ipf_fixoutisn(fr_info_t *fin, ipstate_t *is) 3399 { 3400 tcphdr_t *tcp; 3401 int rev; 3402 u_32_t seq; 3403 3404 tcp = fin->fin_dp; 3405 rev = fin->fin_rev; 3406 if ((is->is_flags & IS_ISNSYN) != 0) { 3407 if ((rev == 0) && (fin->fin_cksum < FI_CK_L4PART)) { 3408 seq = ntohl(tcp->th_seq); 3409 seq += is->is_isninc[0]; 3410 tcp->th_seq = htonl(seq); 3411 ipf_fix_outcksum(0, &tcp->th_sum, is->is_sumd[0], 0); 3412 } 3413 } 3414 if ((is->is_flags & IS_ISNACK) != 0) { 3415 if ((rev == 1) && (fin->fin_cksum < FI_CK_L4PART)) { 3416 seq = ntohl(tcp->th_seq); 3417 seq += is->is_isninc[1]; 3418 tcp->th_seq = htonl(seq); 3419 ipf_fix_outcksum(0, &tcp->th_sum, is->is_sumd[1], 0); 3420 } 3421 } 3422 } 3423 3424 3425 /* ------------------------------------------------------------------------ */ 3426 /* Function: ipf_fixinisn */ 3427 /* Returns: Nil */ 3428 /* Parameters: fin(I) - pointer to packet information */ 3429 /* is(I) - pointer to master state structure */ 3430 /* */ 3431 /* Called only for inbound packets, adjusts the acknowledge number and the */ 3432 /* TCP checksum to match that change. */ 3433 /* ------------------------------------------------------------------------ */ 3434 static void 3435 ipf_fixinisn(fr_info_t *fin, ipstate_t *is) 3436 { 3437 tcphdr_t *tcp; 3438 int rev; 3439 u_32_t ack; 3440 3441 tcp = fin->fin_dp; 3442 rev = fin->fin_rev; 3443 if ((is->is_flags & IS_ISNSYN) != 0) { 3444 if ((rev == 1) && (fin->fin_cksum < FI_CK_L4PART)) { 3445 ack = ntohl(tcp->th_ack); 3446 ack -= is->is_isninc[0]; 3447 tcp->th_ack = htonl(ack); 3448 ipf_fix_incksum(0, &tcp->th_sum, is->is_sumd[0], 0); 3449 } 3450 } 3451 if ((is->is_flags & IS_ISNACK) != 0) { 3452 if ((rev == 0) && (fin->fin_cksum < FI_CK_L4PART)) { 3453 ack = ntohl(tcp->th_ack); 3454 ack -= is->is_isninc[1]; 3455 tcp->th_ack = htonl(ack); 3456 ipf_fix_incksum(0, &tcp->th_sum, is->is_sumd[1], 0); 3457 } 3458 } 3459 } 3460 3461 3462 /* ------------------------------------------------------------------------ */ 3463 /* Function: ipf_state_sync */ 3464 /* Returns: Nil */ 3465 /* Parameters: softc(I) - pointer to soft context main structure */ 3466 /* ifp(I) - pointer to interface */ 3467 /* */ 3468 /* Walk through all state entries and if an interface pointer match is */ 3469 /* found then look it up again, based on its name in case the pointer has */ 3470 /* changed since last time. */ 3471 /* */ 3472 /* If ifp is passed in as being non-null then we are only doing updates for */ 3473 /* existing, matching, uses of it. */ 3474 /* ------------------------------------------------------------------------ */ 3475 void 3476 ipf_state_sync(ipf_main_softc_t *softc, void *ifp) 3477 { 3478 ipf_state_softc_t *softs = softc->ipf_state_soft; 3479 ipstate_t *is; 3480 int i; 3481 3482 if (softc->ipf_running <= 0) 3483 return; 3484 3485 WRITE_ENTER(&softc->ipf_state); 3486 3487 if (softc->ipf_running <= 0) { 3488 RWLOCK_EXIT(&softc->ipf_state); 3489 return; 3490 } 3491 3492 for (is = softs->ipf_state_list; is; is = is->is_next) { 3493 /* 3494 * Look up all the interface names in the state entry. 3495 */ 3496 for (i = 0; i < 4; i++) { 3497 if (ifp == NULL || ifp == is->is_ifp[i]) 3498 is->is_ifp[i] = ipf_resolvenic(softc, 3499 is->is_ifname[i], 3500 is->is_v); 3501 } 3502 } 3503 RWLOCK_EXIT(&softc->ipf_state); 3504 } 3505 3506 3507 /* ------------------------------------------------------------------------ */ 3508 /* Function: ipf_state_del */ 3509 /* Returns: int - 0 = deleted, else refernce count on active struct */ 3510 /* Parameters: softc(I) - pointer to soft context main structure */ 3511 /* is(I) - pointer to state structure to delete */ 3512 /* why(I) - if not 0, log reason why it was deleted */ 3513 /* Write Locks: ipf_state */ 3514 /* */ 3515 /* Deletes a state entry from the enumerated list as well as the hash table */ 3516 /* and timeout queue lists. Make adjustments to hash table statistics and */ 3517 /* global counters as required. */ 3518 /* ------------------------------------------------------------------------ */ 3519 static int 3520 ipf_state_del(ipf_main_softc_t *softc, ipstate_t *is, int why) 3521 { 3522 ipf_state_softc_t *softs = softc->ipf_state_soft; 3523 int orphan = 1; 3524 frentry_t *fr; 3525 3526 /* 3527 * Since we want to delete this, remove it from the state table, 3528 * where it can be found & used, first. 3529 */ 3530 if (is->is_phnext != NULL) { 3531 *is->is_phnext = is->is_hnext; 3532 if (is->is_hnext != NULL) 3533 is->is_hnext->is_phnext = is->is_phnext; 3534 if (softs->ipf_state_table[is->is_hv] == NULL) 3535 softs->ipf_state_stats.iss_inuse--; 3536 softs->ipf_state_stats.iss_bucketlen[is->is_hv]--; 3537 3538 is->is_phnext = NULL; 3539 is->is_hnext = NULL; 3540 orphan = 0; 3541 } 3542 3543 /* 3544 * Because ipf_state_stats.iss_wild is a count of entries in the state 3545 * table that have wildcard flags set, only decerement it once 3546 * and do it here. 3547 */ 3548 if (is->is_flags & (SI_WILDP|SI_WILDA)) { 3549 if (!(is->is_flags & SI_CLONED)) { 3550 ATOMIC_DECL(softs->ipf_state_stats.iss_wild); 3551 } 3552 is->is_flags &= ~(SI_WILDP|SI_WILDA); 3553 } 3554 3555 /* 3556 * Next, remove it from the timeout queue it is in. 3557 */ 3558 if (is->is_sti.tqe_ifq != NULL) 3559 ipf_deletequeueentry(&is->is_sti); 3560 3561 /* 3562 * If it is still in use by something else, do not go any further, 3563 * but note that at this point it is now an orphan. How can this 3564 * be? ipf_state_flush() calls ipf_delete() directly because it wants 3565 * to empty the table out and if something has a hold on a state 3566 * entry (such as ipfstat), it'll do the deref path that'll bring 3567 * us back here to do the real delete & free. 3568 */ 3569 MUTEX_ENTER(&is->is_lock); 3570 if (is->is_me != NULL) { 3571 *is->is_me = NULL; 3572 is->is_me = NULL; 3573 is->is_ref--; 3574 } 3575 is->is_ref--; 3576 if (is->is_ref > 0) { 3577 int refs; 3578 3579 refs = is->is_ref; 3580 MUTEX_EXIT(&is->is_lock); 3581 if (!orphan) 3582 softs->ipf_state_stats.iss_orphan++; 3583 return refs; 3584 } 3585 3586 fr = is->is_rule; 3587 is->is_rule = NULL; 3588 if (fr != NULL) { 3589 if (fr->fr_srctrack.ht_max_nodes != 0) { 3590 (void) ipf_ht_node_del(&fr->fr_srctrack, 3591 is->is_family, &is->is_src); 3592 } 3593 } 3594 3595 ASSERT(is->is_ref == 0); 3596 MUTEX_EXIT(&is->is_lock); 3597 3598 if (is->is_tqehead[0] != NULL) { 3599 if (ipf_deletetimeoutqueue(is->is_tqehead[0]) == 0) 3600 ipf_freetimeoutqueue(softc, is->is_tqehead[0]); 3601 } 3602 if (is->is_tqehead[1] != NULL) { 3603 if (ipf_deletetimeoutqueue(is->is_tqehead[1]) == 0) 3604 ipf_freetimeoutqueue(softc, is->is_tqehead[1]); 3605 } 3606 3607 if (is->is_sync) 3608 ipf_sync_del_state(softc->ipf_sync_soft, is->is_sync); 3609 3610 /* 3611 * Now remove it from the linked list of known states 3612 */ 3613 if (is->is_pnext != NULL) { 3614 *is->is_pnext = is->is_next; 3615 3616 if (is->is_next != NULL) 3617 is->is_next->is_pnext = is->is_pnext; 3618 3619 is->is_pnext = NULL; 3620 is->is_next = NULL; 3621 } 3622 3623 if (softs->ipf_state_logging != 0 && why != 0) 3624 ipf_state_log(softc, is, why); 3625 3626 if (is->is_p == IPPROTO_TCP) 3627 softs->ipf_state_stats.iss_fin++; 3628 else 3629 softs->ipf_state_stats.iss_expire++; 3630 if (orphan) 3631 softs->ipf_state_stats.iss_orphan--; 3632 3633 if (fr != NULL) { 3634 fr->fr_statecnt--; 3635 (void) ipf_derefrule(softc, &fr); 3636 } 3637 3638 softs->ipf_state_stats.iss_active_proto[is->is_p]--; 3639 3640 MUTEX_DESTROY(&is->is_lock); 3641 KFREE(is); 3642 softs->ipf_state_stats.iss_active--; 3643 3644 return 0; 3645 } 3646 3647 3648 /* ------------------------------------------------------------------------ */ 3649 /* Function: ipf_state_expire */ 3650 /* Returns: Nil */ 3651 /* Parameters: softc(I) - pointer to soft context main structure */ 3652 /* */ 3653 /* Slowly expire held state for thingslike UDP and ICMP. The algorithm */ 3654 /* used here is to keep the queue sorted with the oldest things at the top */ 3655 /* and the youngest at the bottom. So if the top one doesn't need to be */ 3656 /* expired then neither will any under it. */ 3657 /* ------------------------------------------------------------------------ */ 3658 void 3659 ipf_state_expire(ipf_main_softc_t *softc) 3660 { 3661 ipf_state_softc_t *softs = softc->ipf_state_soft; 3662 ipftq_t *ifq, *ifqnext; 3663 ipftqent_t *tqe, *tqn; 3664 ipstate_t *is; 3665 SPL_INT(s); 3666 3667 SPL_NET(s); 3668 WRITE_ENTER(&softc->ipf_state); 3669 for (ifq = softs->ipf_state_tcptq; ifq != NULL; ifq = ifq->ifq_next) 3670 for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) { 3671 if (tqe->tqe_die > softc->ipf_ticks) 3672 break; 3673 tqn = tqe->tqe_next; 3674 is = tqe->tqe_parent; 3675 ipf_state_del(softc, is, ISL_EXPIRE); 3676 } 3677 3678 for (ifq = softs->ipf_state_usertq; ifq != NULL; ifq = ifqnext) { 3679 ifqnext = ifq->ifq_next; 3680 3681 for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) { 3682 if (tqe->tqe_die > softc->ipf_ticks) 3683 break; 3684 tqn = tqe->tqe_next; 3685 is = tqe->tqe_parent; 3686 ipf_state_del(softc, is, ISL_EXPIRE); 3687 } 3688 } 3689 3690 for (ifq = softs->ipf_state_usertq; ifq != NULL; ifq = ifqnext) { 3691 ifqnext = ifq->ifq_next; 3692 3693 if (((ifq->ifq_flags & IFQF_DELETE) != 0) && 3694 (ifq->ifq_ref == 0)) { 3695 ipf_freetimeoutqueue(softc, ifq); 3696 } 3697 } 3698 3699 if (softs->ipf_state_doflush) { 3700 (void) ipf_state_flush(softc, 2, 0); 3701 softs->ipf_state_doflush = 0; 3702 softs->ipf_state_wm_last = softc->ipf_ticks; 3703 } 3704 3705 RWLOCK_EXIT(&softc->ipf_state); 3706 SPL_X(s); 3707 } 3708 3709 3710 /* ------------------------------------------------------------------------ */ 3711 /* Function: ipf_state_flush */ 3712 /* Returns: int - 0 == success, -1 == failure */ 3713 /* Parameters: softc(I) - pointer to soft context main structure */ 3714 /* which(I) - which flush action to perform */ 3715 /* proto(I) - which protocol to flush (0 == ALL) */ 3716 /* Write Locks: ipf_state */ 3717 /* */ 3718 /* Flush state tables. Three actions currently defined: */ 3719 /* which == 0 : flush all state table entries */ 3720 /* which == 1 : flush TCP connections which have started to close but are */ 3721 /* stuck for some reason. */ 3722 /* which == 2 : flush TCP connections which have been idle for a long time, */ 3723 /* starting at > 4 days idle and working back in successive half-*/ 3724 /* days to at most 12 hours old. If this fails to free enough */ 3725 /* slots then work backwards in half hour slots to 30 minutes. */ 3726 /* If that too fails, then work backwards in 30 second intervals */ 3727 /* for the last 30 minutes to at worst 30 seconds idle. */ 3728 /* ------------------------------------------------------------------------ */ 3729 int 3730 ipf_state_flush(ipf_main_softc_t *softc, int which, int proto) 3731 { 3732 ipf_state_softc_t *softs = softc->ipf_state_soft; 3733 ipftqent_t *tqe, *tqn; 3734 ipstate_t *is, **isp; 3735 ipftq_t *ifq; 3736 int removed; 3737 SPL_INT(s); 3738 3739 removed = 0; 3740 3741 SPL_NET(s); 3742 3743 switch (which) 3744 { 3745 case 0 : 3746 SBUMP(ipf_state_stats.iss_flush_all); 3747 /* 3748 * Style 0 flush removes everything... 3749 */ 3750 for (isp = &softs->ipf_state_list; ((is = *isp) != NULL); ) { 3751 if ((proto != 0) && (is->is_v != proto)) { 3752 isp = &is->is_next; 3753 continue; 3754 } 3755 if (ipf_state_del(softc, is, ISL_FLUSH) == 0) 3756 removed++; 3757 else 3758 isp = &is->is_next; 3759 } 3760 break; 3761 3762 case 1 : 3763 SBUMP(ipf_state_stats.iss_flush_closing); 3764 /* 3765 * Since we're only interested in things that are closing, 3766 * we can start with the appropriate timeout queue. 3767 */ 3768 for (ifq = softs->ipf_state_tcptq + IPF_TCPS_CLOSE_WAIT; 3769 ifq != NULL; ifq = ifq->ifq_next) { 3770 3771 for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) { 3772 tqn = tqe->tqe_next; 3773 is = tqe->tqe_parent; 3774 if (is->is_p != IPPROTO_TCP) 3775 break; 3776 if (ipf_state_del(softc, is, ISL_FLUSH) == 0) 3777 removed++; 3778 } 3779 } 3780 3781 /* 3782 * Also need to look through the user defined queues. 3783 */ 3784 for (ifq = softs->ipf_state_usertq; ifq != NULL; 3785 ifq = ifq->ifq_next) { 3786 for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) { 3787 tqn = tqe->tqe_next; 3788 is = tqe->tqe_parent; 3789 if (is->is_p != IPPROTO_TCP) 3790 continue; 3791 3792 if ((is->is_state[0] > IPF_TCPS_ESTABLISHED) && 3793 (is->is_state[1] > IPF_TCPS_ESTABLISHED)) { 3794 if (ipf_state_del(softc, is, 3795 ISL_FLUSH) == 0) 3796 removed++; 3797 } 3798 } 3799 } 3800 break; 3801 3802 case 2 : 3803 break; 3804 3805 /* 3806 * Args 5-11 correspond to flushing those particular states 3807 * for TCP connections. 3808 */ 3809 case IPF_TCPS_CLOSE_WAIT : 3810 case IPF_TCPS_FIN_WAIT_1 : 3811 case IPF_TCPS_CLOSING : 3812 case IPF_TCPS_LAST_ACK : 3813 case IPF_TCPS_FIN_WAIT_2 : 3814 case IPF_TCPS_TIME_WAIT : 3815 case IPF_TCPS_CLOSED : 3816 SBUMP(ipf_state_stats.iss_flush_queue); 3817 tqn = softs->ipf_state_tcptq[which].ifq_head; 3818 while (tqn != NULL) { 3819 tqe = tqn; 3820 tqn = tqe->tqe_next; 3821 is = tqe->tqe_parent; 3822 if (ipf_state_del(softc, is, ISL_FLUSH) == 0) 3823 removed++; 3824 } 3825 break; 3826 3827 default : 3828 if (which < 30) 3829 break; 3830 3831 SBUMP(ipf_state_stats.iss_flush_state); 3832 /* 3833 * Take a large arbitrary number to mean the number of seconds 3834 * for which which consider to be the maximum value we'll allow 3835 * the expiration to be. 3836 */ 3837 which = IPF_TTLVAL(which); 3838 for (isp = &softs->ipf_state_list; ((is = *isp) != NULL); ) { 3839 if ((proto == 0) || (is->is_v == proto)) { 3840 if (softc->ipf_ticks - is->is_touched > which) { 3841 if (ipf_state_del(softc, is, 3842 ISL_FLUSH) == 0) { 3843 removed++; 3844 continue; 3845 } 3846 } 3847 } 3848 isp = &is->is_next; 3849 } 3850 break; 3851 } 3852 3853 if (which != 2) { 3854 SPL_X(s); 3855 return removed; 3856 } 3857 3858 SBUMP(ipf_state_stats.iss_flush_timeout); 3859 /* 3860 * Asked to remove inactive entries because the table is full, try 3861 * again, 3 times, if first attempt failed with a different criteria 3862 * each time. The order tried in must be in decreasing age. 3863 * Another alternative is to implement random drop and drop N entries 3864 * at random until N have been freed up. 3865 */ 3866 if (softc->ipf_ticks - softs->ipf_state_wm_last > 3867 softs->ipf_state_wm_freq) { 3868 removed = ipf_queueflush(softc, ipf_state_flush_entry, 3869 softs->ipf_state_tcptq, 3870 softs->ipf_state_usertq, 3871 &softs->ipf_state_stats.iss_active, 3872 softs->ipf_state_size, 3873 softs->ipf_state_wm_low); 3874 softs->ipf_state_wm_last = softc->ipf_ticks; 3875 } 3876 3877 SPL_X(s); 3878 return removed; 3879 } 3880 3881 3882 /* ------------------------------------------------------------------------ */ 3883 /* Function: ipf_state_flush_entry */ 3884 /* Returns: int - 0 = entry deleted, else not deleted */ 3885 /* Parameters: softc(I) - pointer to soft context main structure */ 3886 /* entry(I) - pointer to state structure to delete */ 3887 /* Write Locks: ipf_state */ 3888 /* */ 3889 /* This function is a stepping stone between ipf_queueflush() and */ 3890 /* ipf_state_del(). It is used so we can provide a uniform interface via */ 3891 /* the ipf_queueflush() function. */ 3892 /* ------------------------------------------------------------------------ */ 3893 static int 3894 ipf_state_flush_entry(ipf_main_softc_t *softc, void *entry) 3895 { 3896 return ipf_state_del(softc, entry, ISL_FLUSH); 3897 } 3898 3899 3900 /* ------------------------------------------------------------------------ */ 3901 /* Function: ipf_tcp_age */ 3902 /* Returns: int - 1 == state transition made, 0 == no change (rejected) */ 3903 /* Parameters: tqe(I) - pointer to timeout queue information */ 3904 /* fin(I) - pointer to packet information */ 3905 /* tqtab(I) - TCP timeout queue table this is in */ 3906 /* flags(I) - flags from state/NAT entry */ 3907 /* ok(I) - can we advance state */ 3908 /* */ 3909 /* Rewritten by Arjan de Vet <Arjan.deVet@adv.iae.nl>, 2000-07-29: */ 3910 /* */ 3911 /* - (try to) base state transitions on real evidence only, */ 3912 /* i.e. packets that are sent and have been received by ipfilter; */ 3913 /* diagram 18.12 of TCP/IP volume 1 by W. Richard Stevens was used. */ 3914 /* */ 3915 /* - deal with half-closed connections correctly; */ 3916 /* */ 3917 /* - store the state of the source in state[0] such that ipfstat */ 3918 /* displays the state as source/dest instead of dest/source; the calls */ 3919 /* to ipf_tcp_age have been changed accordingly. */ 3920 /* */ 3921 /* Internal Parameters: */ 3922 /* */ 3923 /* state[0] = state of source (host that initiated connection) */ 3924 /* state[1] = state of dest (host that accepted the connection) */ 3925 /* */ 3926 /* dir == 0 : a packet from source to dest */ 3927 /* dir == 1 : a packet from dest to source */ 3928 /* */ 3929 /* A typical procession for a connection is as follows: */ 3930 /* */ 3931 /* +--------------+-------------------+ */ 3932 /* | Side '0' | Side '1' | */ 3933 /* +--------------+-------------------+ */ 3934 /* | 0 -> 1 (SYN) | | */ 3935 /* | | 0 -> 2 (SYN-ACK) | */ 3936 /* | 1 -> 3 (ACK) | | */ 3937 /* | | 2 -> 4 (ACK-PUSH) | */ 3938 /* | 3 -> 4 (ACK) | | */ 3939 /* | ... | ... | */ 3940 /* | | 4 -> 6 (FIN-ACK) | */ 3941 /* | 4 -> 5 (ACK) | | */ 3942 /* | | 6 -> 6 (ACK-PUSH) | */ 3943 /* | 5 -> 5 (ACK) | | */ 3944 /* | 5 -> 8 (FIN) | | */ 3945 /* | | 6 -> 10 (ACK) | */ 3946 /* +--------------+-------------------+ */ 3947 /* */ 3948 /* Locking: it is assumed that the parent of the tqe structure is locked. */ 3949 /* ------------------------------------------------------------------------ */ 3950 int 3951 ipf_tcp_age(ipftqent_t *tqe, fr_info_t *fin, ipftq_t *tqtab, int flags, int ok) 3952 { 3953 ipf_main_softc_t *softc = fin->fin_main_soft; 3954 int dlen, ostate, nstate, rval, dir; 3955 u_char tcpflags; 3956 tcphdr_t *tcp; 3957 3958 tcp = fin->fin_dp; 3959 3960 rval = 0; 3961 dir = fin->fin_rev; 3962 tcpflags = tcp->th_flags; 3963 dlen = fin->fin_dlen - (TCP_OFF(tcp) << 2); 3964 ostate = tqe->tqe_state[1 - dir]; 3965 nstate = tqe->tqe_state[dir]; 3966 3967 if (tcpflags & TH_RST) { 3968 if (!(tcpflags & TH_PUSH) && !dlen) 3969 nstate = IPF_TCPS_CLOSED; 3970 else 3971 nstate = IPF_TCPS_CLOSE_WAIT; 3972 3973 if (ostate <= IPF_TCPS_ESTABLISHED) { 3974 tqe->tqe_state[1 - dir] = IPF_TCPS_CLOSE_WAIT; 3975 } 3976 rval = 1; 3977 } else { 3978 switch (nstate) 3979 { 3980 case IPF_TCPS_LISTEN: /* 0 */ 3981 if ((tcpflags & TH_OPENING) == TH_OPENING) { 3982 /* 3983 * 'dir' received an S and sends SA in 3984 * response, LISTEN -> SYN_RECEIVED 3985 */ 3986 nstate = IPF_TCPS_SYN_RECEIVED; 3987 rval = 1; 3988 } else if ((tcpflags & TH_OPENING) == TH_SYN) { 3989 /* 'dir' sent S, LISTEN -> SYN_SENT */ 3990 nstate = IPF_TCPS_SYN_SENT; 3991 rval = 1; 3992 } 3993 /* 3994 * the next piece of code makes it possible to get 3995 * already established connections into the state table 3996 * after a restart or reload of the filter rules; this 3997 * does not work when a strict 'flags S keep state' is 3998 * used for tcp connections of course 3999 */ 4000 if (((flags & IS_TCPFSM) == 0) && 4001 ((tcpflags & TH_ACKMASK) == TH_ACK)) { 4002 /* 4003 * we saw an A, guess 'dir' is in ESTABLISHED 4004 * mode 4005 */ 4006 switch (ostate) 4007 { 4008 case IPF_TCPS_LISTEN : 4009 case IPF_TCPS_SYN_RECEIVED : 4010 nstate = IPF_TCPS_HALF_ESTAB; 4011 rval = 1; 4012 break; 4013 case IPF_TCPS_HALF_ESTAB : 4014 case IPF_TCPS_ESTABLISHED : 4015 nstate = IPF_TCPS_ESTABLISHED; 4016 rval = 1; 4017 break; 4018 default : 4019 break; 4020 } 4021 } 4022 /* 4023 * TODO: besides regular ACK packets we can have other 4024 * packets as well; it is yet to be determined how we 4025 * should initialize the states in those cases 4026 */ 4027 break; 4028 4029 case IPF_TCPS_SYN_SENT: /* 1 */ 4030 if ((tcpflags & ~(TH_ECN|TH_CWR)) == TH_SYN) { 4031 /* 4032 * A retransmitted SYN packet. We do not reset 4033 * the timeout here to ipf_tcptimeout because a 4034 * connection connect timeout does not renew 4035 * after every packet that is sent. We need to 4036 * set rval so as to indicate the packet has 4037 * passed the check for its flags being valid 4038 * in the TCP FSM. Setting rval to 2 has the 4039 * result of not resetting the timeout. 4040 */ 4041 rval = 2; 4042 } else if ((tcpflags & (TH_SYN|TH_FIN|TH_ACK)) == 4043 TH_ACK) { 4044 /* 4045 * we see an A from 'dir' which is in SYN_SENT 4046 * state: 'dir' sent an A in response to an SA 4047 * which it received, SYN_SENT -> ESTABLISHED 4048 */ 4049 nstate = IPF_TCPS_ESTABLISHED; 4050 rval = 1; 4051 } else if (tcpflags & TH_FIN) { 4052 /* 4053 * we see an F from 'dir' which is in SYN_SENT 4054 * state and wants to close its side of the 4055 * connection; SYN_SENT -> FIN_WAIT_1 4056 */ 4057 nstate = IPF_TCPS_FIN_WAIT_1; 4058 rval = 1; 4059 } else if ((tcpflags & TH_OPENING) == TH_OPENING) { 4060 /* 4061 * we see an SA from 'dir' which is already in 4062 * SYN_SENT state, this means we have a 4063 * simultaneous open; SYN_SENT -> SYN_RECEIVED 4064 */ 4065 nstate = IPF_TCPS_SYN_RECEIVED; 4066 rval = 1; 4067 } 4068 break; 4069 4070 case IPF_TCPS_SYN_RECEIVED: /* 2 */ 4071 if ((tcpflags & (TH_SYN|TH_FIN|TH_ACK)) == TH_ACK) { 4072 /* 4073 * we see an A from 'dir' which was in 4074 * SYN_RECEIVED state so it must now be in 4075 * established state, SYN_RECEIVED -> 4076 * ESTABLISHED 4077 */ 4078 nstate = IPF_TCPS_ESTABLISHED; 4079 rval = 1; 4080 } else if ((tcpflags & ~(TH_ECN|TH_CWR)) == 4081 TH_OPENING) { 4082 /* 4083 * We see an SA from 'dir' which is already in 4084 * SYN_RECEIVED state. 4085 */ 4086 rval = 2; 4087 } else if (tcpflags & TH_FIN) { 4088 /* 4089 * we see an F from 'dir' which is in 4090 * SYN_RECEIVED state and wants to close its 4091 * side of the connection; SYN_RECEIVED -> 4092 * FIN_WAIT_1 4093 */ 4094 nstate = IPF_TCPS_FIN_WAIT_1; 4095 rval = 1; 4096 } 4097 break; 4098 4099 case IPF_TCPS_HALF_ESTAB: /* 3 */ 4100 if (tcpflags & TH_FIN) { 4101 nstate = IPF_TCPS_FIN_WAIT_1; 4102 rval = 1; 4103 } else if ((tcpflags & TH_ACKMASK) == TH_ACK) { 4104 /* 4105 * If we've picked up a connection in mid 4106 * flight, we could be looking at a follow on 4107 * packet from the same direction as the one 4108 * that created this state. Recognise it but 4109 * do not advance the entire connection's 4110 * state. 4111 */ 4112 switch (ostate) 4113 { 4114 case IPF_TCPS_LISTEN : 4115 case IPF_TCPS_SYN_SENT : 4116 case IPF_TCPS_SYN_RECEIVED : 4117 rval = 1; 4118 break; 4119 case IPF_TCPS_HALF_ESTAB : 4120 case IPF_TCPS_ESTABLISHED : 4121 nstate = IPF_TCPS_ESTABLISHED; 4122 rval = 1; 4123 break; 4124 default : 4125 break; 4126 } 4127 } 4128 break; 4129 4130 case IPF_TCPS_ESTABLISHED: /* 4 */ 4131 rval = 1; 4132 if (tcpflags & TH_FIN) { 4133 /* 4134 * 'dir' closed its side of the connection; 4135 * this gives us a half-closed connection; 4136 * ESTABLISHED -> FIN_WAIT_1 4137 */ 4138 if (ostate == IPF_TCPS_FIN_WAIT_1) { 4139 nstate = IPF_TCPS_CLOSING; 4140 } else { 4141 nstate = IPF_TCPS_FIN_WAIT_1; 4142 } 4143 } else if (tcpflags & TH_ACK) { 4144 /* 4145 * an ACK, should we exclude other flags here? 4146 */ 4147 if (ostate == IPF_TCPS_FIN_WAIT_1) { 4148 /* 4149 * We know the other side did an active 4150 * close, so we are ACKing the recvd 4151 * FIN packet (does the window matching 4152 * code guarantee this?) and go into 4153 * CLOSE_WAIT state; this gives us a 4154 * half-closed connection 4155 */ 4156 nstate = IPF_TCPS_CLOSE_WAIT; 4157 } else if (ostate < IPF_TCPS_CLOSE_WAIT) { 4158 /* 4159 * still a fully established 4160 * connection reset timeout 4161 */ 4162 nstate = IPF_TCPS_ESTABLISHED; 4163 } 4164 } 4165 break; 4166 4167 case IPF_TCPS_CLOSE_WAIT: /* 5 */ 4168 rval = 1; 4169 if (tcpflags & TH_FIN) { 4170 /* 4171 * application closed and 'dir' sent a FIN, 4172 * we're now going into LAST_ACK state 4173 */ 4174 nstate = IPF_TCPS_LAST_ACK; 4175 } else { 4176 /* 4177 * we remain in CLOSE_WAIT because the other 4178 * side has closed already and we did not 4179 * close our side yet; reset timeout 4180 */ 4181 nstate = IPF_TCPS_CLOSE_WAIT; 4182 } 4183 break; 4184 4185 case IPF_TCPS_FIN_WAIT_1: /* 6 */ 4186 rval = 1; 4187 if ((tcpflags & TH_ACK) && 4188 ostate > IPF_TCPS_CLOSE_WAIT) { 4189 /* 4190 * if the other side is not active anymore 4191 * it has sent us a FIN packet that we are 4192 * ack'ing now with an ACK; this means both 4193 * sides have now closed the connection and 4194 * we go into TIME_WAIT 4195 */ 4196 /* 4197 * XXX: how do we know we really are ACKing 4198 * the FIN packet here? does the window code 4199 * guarantee that? 4200 */ 4201 nstate = IPF_TCPS_LAST_ACK; 4202 } else { 4203 /* 4204 * we closed our side of the connection 4205 * already but the other side is still active 4206 * (ESTABLISHED/CLOSE_WAIT); continue with 4207 * this half-closed connection 4208 */ 4209 nstate = IPF_TCPS_FIN_WAIT_1; 4210 } 4211 break; 4212 4213 case IPF_TCPS_CLOSING: /* 7 */ 4214 if ((tcpflags & (TH_FIN|TH_ACK)) == TH_ACK) { 4215 nstate = IPF_TCPS_TIME_WAIT; 4216 } 4217 rval = 1; 4218 break; 4219 4220 case IPF_TCPS_LAST_ACK: /* 8 */ 4221 if (tcpflags & TH_ACK) { 4222 rval = 1; 4223 } 4224 /* 4225 * we cannot detect when we go out of LAST_ACK state 4226 * to CLOSED because that is based on the reception 4227 * of ACK packets; ipfilter can only detect that a 4228 * packet has been sent by a host 4229 */ 4230 break; 4231 4232 case IPF_TCPS_FIN_WAIT_2: /* 9 */ 4233 /* NOT USED */ 4234 break; 4235 4236 case IPF_TCPS_TIME_WAIT: /* 10 */ 4237 /* we're in 2MSL timeout now */ 4238 if (ostate == IPF_TCPS_LAST_ACK) { 4239 nstate = IPF_TCPS_CLOSED; 4240 rval = 1; 4241 } else { 4242 rval = 2; 4243 } 4244 break; 4245 4246 case IPF_TCPS_CLOSED: /* 11 */ 4247 rval = 2; 4248 break; 4249 4250 default : 4251 #if !defined(_KERNEL) 4252 abort(); 4253 #endif 4254 break; 4255 } 4256 } 4257 4258 /* 4259 * If rval == 2 then do not update the queue position, but treat the 4260 * packet as being ok. 4261 */ 4262 if (rval == 2) 4263 rval = 1; 4264 else if (rval == 1) { 4265 if (ok) 4266 tqe->tqe_state[dir] = nstate; 4267 if ((tqe->tqe_flags & TQE_RULEBASED) == 0) 4268 ipf_movequeue(softc->ipf_ticks, tqe, tqe->tqe_ifq, 4269 tqtab + nstate); 4270 } 4271 4272 return rval; 4273 } 4274 4275 4276 /* ------------------------------------------------------------------------ */ 4277 /* Function: ipf_state_log */ 4278 /* Returns: Nil */ 4279 /* Parameters: softc(I) - pointer to soft context main structure */ 4280 /* is(I) - pointer to state structure */ 4281 /* type(I) - type of log entry to create */ 4282 /* */ 4283 /* Creates a state table log entry using the state structure and type info. */ 4284 /* passed in. Log packet/byte counts, source/destination address and other */ 4285 /* protocol specific information. */ 4286 /* ------------------------------------------------------------------------ */ 4287 void 4288 ipf_state_log(ipf_main_softc_t *softc, struct ipstate *is, u_int type) 4289 { 4290 #ifdef IPFILTER_LOG 4291 struct ipslog ipsl; 4292 size_t sizes[1]; 4293 void *items[1]; 4294 int types[1]; 4295 4296 /* 4297 * Copy information out of the ipstate_t structure and into the 4298 * structure used for logging. 4299 */ 4300 ipsl.isl_type = type; 4301 ipsl.isl_pkts[0] = is->is_pkts[0] + is->is_icmppkts[0]; 4302 ipsl.isl_bytes[0] = is->is_bytes[0]; 4303 ipsl.isl_pkts[1] = is->is_pkts[1] + is->is_icmppkts[1]; 4304 ipsl.isl_bytes[1] = is->is_bytes[1]; 4305 ipsl.isl_pkts[2] = is->is_pkts[2] + is->is_icmppkts[2]; 4306 ipsl.isl_bytes[2] = is->is_bytes[2]; 4307 ipsl.isl_pkts[3] = is->is_pkts[3] + is->is_icmppkts[3]; 4308 ipsl.isl_bytes[3] = is->is_bytes[3]; 4309 ipsl.isl_src = is->is_src; 4310 ipsl.isl_dst = is->is_dst; 4311 ipsl.isl_p = is->is_p; 4312 ipsl.isl_v = is->is_v; 4313 ipsl.isl_flags = is->is_flags; 4314 ipsl.isl_tag = is->is_tag; 4315 ipsl.isl_rulen = is->is_rulen; 4316 (void) strncpy(ipsl.isl_group, is->is_group, FR_GROUPLEN); 4317 4318 if (ipsl.isl_p == IPPROTO_TCP || ipsl.isl_p == IPPROTO_UDP) { 4319 ipsl.isl_sport = is->is_sport; 4320 ipsl.isl_dport = is->is_dport; 4321 if (ipsl.isl_p == IPPROTO_TCP) { 4322 ipsl.isl_state[0] = is->is_state[0]; 4323 ipsl.isl_state[1] = is->is_state[1]; 4324 } 4325 } else if (ipsl.isl_p == IPPROTO_ICMP) { 4326 ipsl.isl_itype = is->is_icmp.ici_type; 4327 } else if (ipsl.isl_p == IPPROTO_ICMPV6) { 4328 ipsl.isl_itype = is->is_icmp.ici_type; 4329 } else { 4330 ipsl.isl_ps.isl_filler[0] = 0; 4331 ipsl.isl_ps.isl_filler[1] = 0; 4332 } 4333 4334 items[0] = &ipsl; 4335 sizes[0] = sizeof(ipsl); 4336 types[0] = 0; 4337 4338 (void) ipf_log_items(softc, IPL_LOGSTATE, NULL, items, sizes, types, 1); 4339 #endif 4340 } 4341 4342 4343 #ifdef USE_INET6 4344 /* ------------------------------------------------------------------------ */ 4345 /* Function: ipf_checkicmp6matchingstate */ 4346 /* Returns: ipstate_t* - NULL == no match found, */ 4347 /* else pointer to matching state entry */ 4348 /* Parameters: fin(I) - pointer to packet information */ 4349 /* Locks: NULL == no locks, else Read Lock on ipf_state */ 4350 /* */ 4351 /* If we've got an ICMPv6 error message, using the information stored in */ 4352 /* the ICMPv6 packet, look for a matching state table entry. */ 4353 /* ------------------------------------------------------------------------ */ 4354 static ipstate_t * 4355 ipf_checkicmp6matchingstate(fr_info_t *fin) 4356 { 4357 ipf_main_softc_t *softc = fin->fin_main_soft; 4358 ipf_state_softc_t *softs = softc->ipf_state_soft; 4359 struct icmp6_hdr *ic6, *oic; 4360 ipstate_t *is, **isp; 4361 u_short sport, dport; 4362 i6addr_t dst, src; 4363 u_short savelen; 4364 icmpinfo_t *ic; 4365 fr_info_t ofin; 4366 tcphdr_t *tcp; 4367 ip6_t *oip6; 4368 u_char pr; 4369 u_int hv; 4370 int type; 4371 4372 /* 4373 * Does it at least have the return (basic) IP header ? 4374 * Is it an actual recognised ICMP error type? 4375 * Only a basic IP header (no options) should be with 4376 * an ICMP error header. 4377 */ 4378 if ((fin->fin_v != 6) || (fin->fin_plen < ICMP6ERR_MINPKTLEN) || 4379 !(fin->fin_flx & FI_ICMPERR)) { 4380 SBUMPD(ipf_state_stats, iss_icmp_bad); 4381 return NULL; 4382 } 4383 4384 ic6 = fin->fin_dp; 4385 type = ic6->icmp6_type; 4386 4387 oip6 = (ip6_t *)((char *)ic6 + ICMPERR_ICMPHLEN); 4388 if (fin->fin_plen < sizeof(*oip6)) { 4389 SBUMPD(ipf_state_stats, iss_icmp_short); 4390 return NULL; 4391 } 4392 4393 bcopy((char *)fin, (char *)&ofin, sizeof(*fin)); 4394 ofin.fin_v = 6; 4395 ofin.fin_ifp = fin->fin_ifp; 4396 ofin.fin_out = !fin->fin_out; 4397 ofin.fin_m = NULL; /* if dereferenced, panic XXX */ 4398 ofin.fin_mp = NULL; /* if dereferenced, panic XXX */ 4399 4400 /* 4401 * We make a fin entry to be able to feed it to 4402 * matchsrcdst. Note that not all fields are necessary 4403 * but this is the cleanest way. Note further we fill 4404 * in fin_mp such that if someone uses it we'll get 4405 * a kernel panic. ipf_matchsrcdst does not use this. 4406 * 4407 * watch out here, as ip is in host order and oip6 in network 4408 * order. Any change we make must be undone afterwards. 4409 */ 4410 savelen = oip6->ip6_plen; 4411 oip6->ip6_plen = htons(fin->fin_dlen - ICMPERR_ICMPHLEN); 4412 ofin.fin_flx = FI_NOCKSUM; 4413 ofin.fin_ip = (ip_t *)oip6; 4414 (void) ipf_makefrip(sizeof(*oip6), (ip_t *)oip6, &ofin); 4415 ofin.fin_flx &= ~(FI_BAD|FI_SHORT); 4416 oip6->ip6_plen = savelen; 4417 pr = ofin.fin_p; 4418 4419 /* 4420 * an ICMP error can never generate an ICMP error in response. 4421 */ 4422 if (ofin.fin_flx & FI_ICMPERR) { 4423 DT1(iss_icmp6_icmperr, fr_info_t *, &ofin); 4424 SBUMP(ipf_state_stats.iss_icmp6_icmperr); 4425 return NULL; 4426 } 4427 4428 if (oip6->ip6_nxt == IPPROTO_ICMPV6) { 4429 oic = ofin.fin_dp; 4430 /* 4431 * an ICMP error can only be generated as a result of an 4432 * ICMP query, not as the response on an ICMP error 4433 * 4434 * XXX theoretically ICMP_ECHOREP and the other reply's are 4435 * ICMP query's as well, but adding them here seems strange XXX 4436 */ 4437 if (!(oic->icmp6_type & ICMP6_INFOMSG_MASK)) { 4438 DT1(iss_icmp6_notinfo, fr_info_t *, &ofin); 4439 SBUMP(ipf_state_stats.iss_icmp6_notinfo); 4440 return NULL; 4441 } 4442 4443 /* 4444 * perform a lookup of the ICMP packet in the state table 4445 */ 4446 hv = (pr = oip6->ip6_nxt); 4447 src.in6 = oip6->ip6_src; 4448 hv += src.in4.s_addr; 4449 dst.in6 = oip6->ip6_dst; 4450 hv += dst.in4.s_addr; 4451 hv += oic->icmp6_id; 4452 hv += oic->icmp6_seq; 4453 hv = DOUBLE_HASH(hv); 4454 4455 READ_ENTER(&softc->ipf_state); 4456 for (isp = &softs->ipf_state_table[hv]; 4457 ((is = *isp) != NULL); ) { 4458 ic = &is->is_icmp; 4459 isp = &is->is_hnext; 4460 if ((is->is_p == pr) && 4461 !(is->is_pass & FR_NOICMPERR) && 4462 (oic->icmp6_id == ic->ici_id) && 4463 (oic->icmp6_seq == ic->ici_seq) && 4464 (is = ipf_matchsrcdst(&ofin, is, &src, 4465 &dst, NULL, FI_ICMPCMP))) { 4466 /* 4467 * in the state table ICMP query's are stored 4468 * with the type of the corresponding ICMP 4469 * response. Correct here 4470 */ 4471 if (((ic->ici_type == ICMP6_ECHO_REPLY) && 4472 (oic->icmp6_type == ICMP6_ECHO_REQUEST)) || 4473 (ic->ici_type - 1 == oic->icmp6_type )) { 4474 if (!ipf_allowstateicmp(fin, is, &src)) 4475 return is; 4476 } 4477 } 4478 } 4479 RWLOCK_EXIT(&softc->ipf_state); 4480 SBUMPD(ipf_state_stats, iss_icmp6_miss); 4481 return NULL; 4482 } 4483 4484 hv = (pr = oip6->ip6_nxt); 4485 src.in6 = oip6->ip6_src; 4486 hv += src.i6[0]; 4487 hv += src.i6[1]; 4488 hv += src.i6[2]; 4489 hv += src.i6[3]; 4490 dst.in6 = oip6->ip6_dst; 4491 hv += dst.i6[0]; 4492 hv += dst.i6[1]; 4493 hv += dst.i6[2]; 4494 hv += dst.i6[3]; 4495 4496 tcp = NULL; 4497 4498 switch (oip6->ip6_nxt) 4499 { 4500 case IPPROTO_TCP : 4501 case IPPROTO_UDP : 4502 tcp = (tcphdr_t *)(oip6 + 1); 4503 dport = tcp->th_dport; 4504 sport = tcp->th_sport; 4505 hv += dport; 4506 hv += sport; 4507 break; 4508 4509 case IPPROTO_ICMPV6 : 4510 oic = (struct icmp6_hdr *)(oip6 + 1); 4511 hv += oic->icmp6_id; 4512 hv += oic->icmp6_seq; 4513 break; 4514 4515 default : 4516 break; 4517 } 4518 4519 hv = DOUBLE_HASH(hv); 4520 4521 READ_ENTER(&softc->ipf_state); 4522 for (isp = &softs->ipf_state_table[hv]; ((is = *isp) != NULL); ) { 4523 isp = &is->is_hnext; 4524 /* 4525 * Only allow this icmp though if the 4526 * encapsulated packet was allowed through the 4527 * other way around. Note that the minimal amount 4528 * of info present does not allow for checking against 4529 * tcp internals such as seq and ack numbers. 4530 */ 4531 if ((is->is_p != pr) || (is->is_v != 6) || 4532 (is->is_pass & FR_NOICMPERR)) 4533 continue; 4534 is = ipf_matchsrcdst(&ofin, is, &src, &dst, tcp, FI_ICMPCMP); 4535 if ((is != NULL) && (ipf_allowstateicmp(fin, is, &src) == 0)) 4536 return is; 4537 } 4538 RWLOCK_EXIT(&softc->ipf_state); 4539 SBUMPD(ipf_state_stats, iss_icmp_miss); 4540 return NULL; 4541 } 4542 #endif 4543 4544 4545 /* ------------------------------------------------------------------------ */ 4546 /* Function: ipf_sttab_init */ 4547 /* Returns: Nil */ 4548 /* Parameters: softc(I) - pointer to soft context main structure */ 4549 /* tqp(I) - pointer to an array of timeout queues for TCP */ 4550 /* */ 4551 /* Initialise the array of timeout queues for TCP. */ 4552 /* ------------------------------------------------------------------------ */ 4553 void 4554 ipf_sttab_init(ipf_main_softc_t *softc, ipftq_t *tqp) 4555 { 4556 int i; 4557 4558 for (i = IPF_TCP_NSTATES - 1; i >= 0; i--) { 4559 IPFTQ_INIT(&tqp[i], 0, "ipftq tcp tab"); 4560 tqp[i].ifq_next = tqp + i + 1; 4561 } 4562 tqp[IPF_TCP_NSTATES - 1].ifq_next = NULL; 4563 tqp[IPF_TCPS_CLOSED].ifq_ttl = softc->ipf_tcpclosed; 4564 tqp[IPF_TCPS_LISTEN].ifq_ttl = softc->ipf_tcptimeout; 4565 tqp[IPF_TCPS_SYN_SENT].ifq_ttl = softc->ipf_tcpsynsent; 4566 tqp[IPF_TCPS_SYN_RECEIVED].ifq_ttl = softc->ipf_tcpsynrecv; 4567 tqp[IPF_TCPS_ESTABLISHED].ifq_ttl = softc->ipf_tcpidletimeout; 4568 tqp[IPF_TCPS_CLOSE_WAIT].ifq_ttl = softc->ipf_tcphalfclosed; 4569 tqp[IPF_TCPS_FIN_WAIT_1].ifq_ttl = softc->ipf_tcphalfclosed; 4570 tqp[IPF_TCPS_CLOSING].ifq_ttl = softc->ipf_tcptimeout; 4571 tqp[IPF_TCPS_LAST_ACK].ifq_ttl = softc->ipf_tcplastack; 4572 tqp[IPF_TCPS_FIN_WAIT_2].ifq_ttl = softc->ipf_tcpclosewait; 4573 tqp[IPF_TCPS_TIME_WAIT].ifq_ttl = softc->ipf_tcptimewait; 4574 tqp[IPF_TCPS_HALF_ESTAB].ifq_ttl = softc->ipf_tcptimeout; 4575 } 4576 4577 4578 /* ------------------------------------------------------------------------ */ 4579 /* Function: ipf_sttab_destroy */ 4580 /* Returns: Nil */ 4581 /* Parameters: tqp(I) - pointer to an array of timeout queues for TCP */ 4582 /* */ 4583 /* Do whatever is necessary to "destroy" each of the entries in the array */ 4584 /* of timeout queues for TCP. */ 4585 /* ------------------------------------------------------------------------ */ 4586 void 4587 ipf_sttab_destroy(ipftq_t *tqp) 4588 { 4589 int i; 4590 4591 for (i = IPF_TCP_NSTATES - 1; i >= 0; i--) 4592 MUTEX_DESTROY(&tqp[i].ifq_lock); 4593 } 4594 4595 4596 /* ------------------------------------------------------------------------ */ 4597 /* Function: ipf_state_deref */ 4598 /* Returns: Nil */ 4599 /* Parameters: softc(I) - pointer to soft context main structure */ 4600 /* isp(I) - pointer to pointer to state table entry */ 4601 /* */ 4602 /* Decrement the reference counter for this state table entry and free it */ 4603 /* if there are no more things using it. */ 4604 /* */ 4605 /* This function is only called when cleaning up after increasing is_ref by */ 4606 /* one earlier in the 'code path' so if is_ref is 1 when entering, we do */ 4607 /* have an orphan, otherwise not. However there is a possible race between */ 4608 /* the entry being deleted via flushing with an ioctl call (that calls the */ 4609 /* delete function directly) and the tail end of packet processing so we */ 4610 /* need to grab is_lock before doing the check to synchronise the two code */ 4611 /* paths. */ 4612 /* */ 4613 /* When operating in userland (ipftest), we have no timers to clear a state */ 4614 /* entry. Therefore, we make a few simple tests before deleting an entry */ 4615 /* outright. We compare states on each side looking for a combination of */ 4616 /* TIME_WAIT (should really be FIN_WAIT_2?) and LAST_ACK. Then we factor */ 4617 /* in packet direction with the interface list to make sure we don't */ 4618 /* prematurely delete an entry on a final inbound packet that's we're also */ 4619 /* supposed to route elsewhere. */ 4620 /* */ 4621 /* Internal parameters: */ 4622 /* state[0] = state of source (host that initiated connection) */ 4623 /* state[1] = state of dest (host that accepted the connection) */ 4624 /* */ 4625 /* dir == 0 : a packet from source to dest */ 4626 /* dir == 1 : a packet from dest to source */ 4627 /* ------------------------------------------------------------------------ */ 4628 void 4629 ipf_state_deref(ipf_main_softc_t *softc, ipstate_t **isp) 4630 { 4631 ipstate_t *is = *isp; 4632 4633 is = *isp; 4634 *isp = NULL; 4635 4636 MUTEX_ENTER(&is->is_lock); 4637 if (is->is_ref > 1) { 4638 is->is_ref--; 4639 MUTEX_EXIT(&is->is_lock); 4640 #ifndef _KERNEL 4641 if ((is->is_sti.tqe_state[0] > IPF_TCPS_ESTABLISHED) || 4642 (is->is_sti.tqe_state[1] > IPF_TCPS_ESTABLISHED)) { 4643 ipf_state_del(softc, is, ISL_EXPIRE); 4644 } 4645 #endif 4646 return; 4647 } 4648 MUTEX_EXIT(&is->is_lock); 4649 4650 WRITE_ENTER(&softc->ipf_state); 4651 ipf_state_del(softc, is, ISL_ORPHAN); 4652 RWLOCK_EXIT(&softc->ipf_state); 4653 } 4654 4655 4656 /* ------------------------------------------------------------------------ */ 4657 /* Function: ipf_state_setqueue */ 4658 /* Returns: Nil */ 4659 /* Parameters: softc(I) - pointer to soft context main structure */ 4660 /* is(I) - pointer to state structure */ 4661 /* rev(I) - forward(0) or reverse(1) direction */ 4662 /* Locks: ipf_state (read or write) */ 4663 /* */ 4664 /* Put the state entry on its default queue entry, using rev as a helped in */ 4665 /* determining which queue it should be placed on. */ 4666 /* ------------------------------------------------------------------------ */ 4667 void 4668 ipf_state_setqueue(ipf_main_softc_t *softc, ipstate_t *is, int rev) 4669 { 4670 ipf_state_softc_t *softs = softc->ipf_state_soft; 4671 ipftq_t *oifq, *nifq; 4672 4673 if ((is->is_sti.tqe_flags & TQE_RULEBASED) != 0) 4674 nifq = is->is_tqehead[rev]; 4675 else 4676 nifq = NULL; 4677 4678 if (nifq == NULL) { 4679 switch (is->is_p) 4680 { 4681 #ifdef USE_INET6 4682 case IPPROTO_ICMPV6 : 4683 if (rev == 1) 4684 nifq = &softs->ipf_state_icmpacktq; 4685 else 4686 nifq = &softs->ipf_state_icmptq; 4687 break; 4688 #endif 4689 case IPPROTO_ICMP : 4690 if (rev == 1) 4691 nifq = &softs->ipf_state_icmpacktq; 4692 else 4693 nifq = &softs->ipf_state_icmptq; 4694 break; 4695 case IPPROTO_TCP : 4696 nifq = softs->ipf_state_tcptq + is->is_state[rev]; 4697 break; 4698 4699 case IPPROTO_UDP : 4700 if (rev == 1) 4701 nifq = &softs->ipf_state_udpacktq; 4702 else 4703 nifq = &softs->ipf_state_udptq; 4704 break; 4705 4706 default : 4707 nifq = &softs->ipf_state_iptq; 4708 break; 4709 } 4710 } 4711 4712 oifq = is->is_sti.tqe_ifq; 4713 /* 4714 * If it's currently on a timeout queue, move it from one queue to 4715 * another, else put it on the end of the newly determined queue. 4716 */ 4717 if (oifq != NULL) 4718 ipf_movequeue(softc->ipf_ticks, &is->is_sti, oifq, nifq); 4719 else 4720 ipf_queueappend(softc->ipf_ticks, &is->is_sti, nifq, is); 4721 return; 4722 } 4723 4724 4725 /* ------------------------------------------------------------------------ */ 4726 /* Function: ipf_state_iter */ 4727 /* Returns: int - 0 == success, else error */ 4728 /* Parameters: softc(I) - pointer to main soft context */ 4729 /* token(I) - pointer to ipftoken structure */ 4730 /* itp(I) - pointer to ipfgeniter structure */ 4731 /* obj(I) - pointer to data description structure */ 4732 /* */ 4733 /* This function handles the SIOCGENITER ioctl for the state tables and */ 4734 /* walks through the list of entries in the state table list (softs->ipf_state_list.) */ 4735 /* ------------------------------------------------------------------------ */ 4736 static int 4737 ipf_state_iter(ipf_main_softc_t *softc, ipftoken_t *token, ipfgeniter_t *itp, 4738 ipfobj_t *obj) 4739 { 4740 ipf_state_softc_t *softs = softc->ipf_state_soft; 4741 ipstate_t *is, *next, zero; 4742 int error; 4743 4744 if (itp->igi_data == NULL) { 4745 IPFERROR(100026); 4746 return EFAULT; 4747 } 4748 4749 if (itp->igi_nitems < 1) { 4750 IPFERROR(100027); 4751 return ENOSPC; 4752 } 4753 4754 if (itp->igi_type != IPFGENITER_STATE) { 4755 IPFERROR(100028); 4756 return EINVAL; 4757 } 4758 4759 is = token->ipt_data; 4760 if (is == (void *)-1) { 4761 IPFERROR(100029); 4762 return ESRCH; 4763 } 4764 4765 error = 0; 4766 obj->ipfo_type = IPFOBJ_IPSTATE; 4767 obj->ipfo_size = sizeof(ipstate_t); 4768 4769 READ_ENTER(&softc->ipf_state); 4770 4771 is = token->ipt_data; 4772 if (is == NULL) { 4773 next = softs->ipf_state_list; 4774 } else { 4775 next = is->is_next; 4776 } 4777 4778 /* 4779 * If we find a state entry to use, bump its reference count so that 4780 * it can be used for is_next when we come back. 4781 */ 4782 if (next != NULL) { 4783 MUTEX_ENTER(&next->is_lock); 4784 next->is_ref++; 4785 MUTEX_EXIT(&next->is_lock); 4786 token->ipt_data = next; 4787 } else { 4788 bzero(&zero, sizeof(zero)); 4789 next = &zero; 4790 token->ipt_data = NULL; 4791 } 4792 if (next->is_next == NULL) 4793 ipf_token_mark_complete(token); 4794 4795 RWLOCK_EXIT(&softc->ipf_state); 4796 4797 obj->ipfo_ptr = itp->igi_data; 4798 error = ipf_outobjk(softc, obj, next); 4799 if (is != NULL) 4800 ipf_state_deref(softc, &is); 4801 4802 return error; 4803 } 4804 4805 4806 /* ------------------------------------------------------------------------ */ 4807 /* Function: ipf_state_gettable */ 4808 /* Returns: int - 0 = success, else error */ 4809 /* Parameters: softc(I) - pointer to main soft context */ 4810 /* softs(I) - pointer to state context structure */ 4811 /* data(I) - pointer to ioctl data */ 4812 /* */ 4813 /* This function handles ioctl requests for tables of state information. */ 4814 /* At present the only table it deals with is the hash bucket statistics. */ 4815 /* ------------------------------------------------------------------------ */ 4816 static int 4817 ipf_state_gettable(ipf_main_softc_t *softc, ipf_state_softc_t *softs, 4818 char *data) 4819 { 4820 ipftable_t table; 4821 int error; 4822 4823 error = ipf_inobj(softc, data, NULL, &table, IPFOBJ_GTABLE); 4824 if (error != 0) 4825 return error; 4826 4827 if (table.ita_type != IPFTABLE_BUCKETS) { 4828 IPFERROR(100031); 4829 return EINVAL; 4830 } 4831 4832 error = COPYOUT(softs->ipf_state_stats.iss_bucketlen, table.ita_table, 4833 softs->ipf_state_size * sizeof(u_int)); 4834 if (error != 0) { 4835 IPFERROR(100032); 4836 error = EFAULT; 4837 } 4838 return error; 4839 } 4840 4841 4842 /* ------------------------------------------------------------------------ */ 4843 /* Function: ipf_state_setpending */ 4844 /* Returns: Nil */ 4845 /* Parameters: softc(I) - pointer to main soft context */ 4846 /* is(I) - pointer to state structure */ 4847 /* Locks: ipf_state (read or write) */ 4848 /* */ 4849 /* Put the state entry on to the pending queue - this queue has a very */ 4850 /* short lifetime where items are put that can't be deleted straight away */ 4851 /* because of locking issues but we want to delete them ASAP, anyway. */ 4852 /* ------------------------------------------------------------------------ */ 4853 void 4854 ipf_state_setpending(ipf_main_softc_t *softc, ipstate_t *is) 4855 { 4856 ipf_state_softc_t *softs = softc->ipf_state_soft; 4857 ipftq_t *oifq; 4858 4859 oifq = is->is_sti.tqe_ifq; 4860 if (oifq != NULL) 4861 ipf_movequeue(softc->ipf_ticks, &is->is_sti, oifq, 4862 &softs->ipf_state_pending); 4863 else 4864 ipf_queueappend(softc->ipf_ticks, &is->is_sti, 4865 &softs->ipf_state_pending, is); 4866 4867 MUTEX_ENTER(&is->is_lock); 4868 if (is->is_me != NULL) { 4869 *is->is_me = NULL; 4870 is->is_me = NULL; 4871 is->is_ref--; 4872 } 4873 MUTEX_EXIT(&is->is_lock); 4874 } 4875 4876 4877 /* ------------------------------------------------------------------------ */ 4878 /* Function: ipf_state_matchflush */ 4879 /* Returns: Nil */ 4880 /* Parameters: softc(I) - pointer to main soft context */ 4881 /* data(I) - pointer to state structure */ 4882 /* Locks: ipf_state (read or write) */ 4883 /* */ 4884 /* Flush all entries from the list of state entries that match the */ 4885 /* properties in the array loaded. */ 4886 /* ------------------------------------------------------------------------ */ 4887 int 4888 ipf_state_matchflush(ipf_main_softc_t *softc, void *data) 4889 { 4890 ipf_state_softc_t *softs = softc->ipf_state_soft; 4891 int *array, flushed, error; 4892 ipstate_t *state, *statenext; 4893 ipfobj_t obj; 4894 4895 error = ipf_matcharray_load(softc, data, &obj, &array); 4896 if (error != 0) 4897 return error; 4898 4899 flushed = 0; 4900 4901 for (state = softs->ipf_state_list; state != NULL; state = statenext) { 4902 statenext = state->is_next; 4903 if (ipf_state_matcharray(state, array, softc->ipf_ticks) == 0) { 4904 ipf_state_del(softc, state, ISL_FLUSH); 4905 flushed++; 4906 } 4907 } 4908 4909 obj.ipfo_retval = flushed; 4910 error = BCOPYOUT(&obj, data, sizeof(obj)); 4911 4912 KFREES(array, array[0] * sizeof(*array)); 4913 4914 return error; 4915 } 4916 4917 4918 /* ------------------------------------------------------------------------ */ 4919 /* Function: ipf_state_matcharray */ 4920 /* Returns: int - 0 = no match, 1 = match */ 4921 /* Parameters: state(I) - pointer to state structure */ 4922 /* array(I) - pointer to ipf matching expression */ 4923 /* ticks(I) - current value of ipfilter tick timer */ 4924 /* Locks: ipf_state (read or write) */ 4925 /* */ 4926 /* Compare a state entry with the match array passed in and return a value */ 4927 /* to indicate whether or not the matching was successful. */ 4928 /* ------------------------------------------------------------------------ */ 4929 static int 4930 ipf_state_matcharray(ipstate_t *state, int *array, u_long ticks) 4931 { 4932 int i, n, *x, rv, p; 4933 ipfexp_t *e; 4934 4935 rv = 0; 4936 n = array[0]; 4937 x = array + 1; 4938 4939 for (; n > 0; x += 3 + x[3], rv = 0) { 4940 e = (ipfexp_t *)x; 4941 n -= e->ipfe_size; 4942 if (x[0] == IPF_EXP_END) 4943 break; 4944 4945 /* 4946 * If we need to match the protocol and that doesn't match, 4947 * don't even both with the instruction array. 4948 */ 4949 p = e->ipfe_cmd >> 16; 4950 if ((p != 0) && (p != state->is_p)) 4951 break; 4952 4953 switch (e->ipfe_cmd) 4954 { 4955 case IPF_EXP_IP_PR : 4956 for (i = 0; !rv && i < e->ipfe_narg; i++) { 4957 rv |= (state->is_p == e->ipfe_arg0[i]); 4958 } 4959 break; 4960 4961 case IPF_EXP_IP_SRCADDR : 4962 if (state->is_v != 4) 4963 break; 4964 for (i = 0; !rv && i < e->ipfe_narg; i++) { 4965 rv |= ((state->is_saddr & 4966 e->ipfe_arg0[i * 2 + 1]) == 4967 e->ipfe_arg0[i * 2]); 4968 } 4969 break; 4970 4971 case IPF_EXP_IP_DSTADDR : 4972 if (state->is_v != 4) 4973 break; 4974 for (i = 0; !rv && i < e->ipfe_narg; i++) { 4975 rv |= ((state->is_daddr & 4976 e->ipfe_arg0[i * 2 + 1]) == 4977 e->ipfe_arg0[i * 2]); 4978 } 4979 break; 4980 4981 case IPF_EXP_IP_ADDR : 4982 if (state->is_v != 4) 4983 break; 4984 for (i = 0; !rv && i < e->ipfe_narg; i++) { 4985 rv |= ((state->is_saddr & 4986 e->ipfe_arg0[i * 2 + 1]) == 4987 e->ipfe_arg0[i * 2]) || 4988 ((state->is_daddr & 4989 e->ipfe_arg0[i * 2 + 1]) == 4990 e->ipfe_arg0[i * 2]); 4991 } 4992 break; 4993 4994 #ifdef USE_INET6 4995 case IPF_EXP_IP6_SRCADDR : 4996 if (state->is_v != 6) 4997 break; 4998 for (i = 0; !rv && i < x[3]; i++) { 4999 rv |= IP6_MASKEQ(&state->is_src.in6, 5000 &e->ipfe_arg0[i * 8 + 4], 5001 &e->ipfe_arg0[i * 8]); 5002 } 5003 break; 5004 5005 case IPF_EXP_IP6_DSTADDR : 5006 if (state->is_v != 6) 5007 break; 5008 for (i = 0; !rv && i < x[3]; i++) { 5009 rv |= IP6_MASKEQ(&state->is_dst.in6, 5010 &e->ipfe_arg0[i * 8 + 4], 5011 &e->ipfe_arg0[i * 8]); 5012 } 5013 break; 5014 5015 case IPF_EXP_IP6_ADDR : 5016 if (state->is_v != 6) 5017 break; 5018 for (i = 0; !rv && i < x[3]; i++) { 5019 rv |= IP6_MASKEQ(&state->is_src.in6, 5020 &e->ipfe_arg0[i * 8 + 4], 5021 &e->ipfe_arg0[i * 8]) || 5022 IP6_MASKEQ(&state->is_dst.in6, 5023 &e->ipfe_arg0[i * 8 + 4], 5024 &e->ipfe_arg0[i * 8]); 5025 } 5026 break; 5027 #endif 5028 5029 case IPF_EXP_UDP_PORT : 5030 case IPF_EXP_TCP_PORT : 5031 for (i = 0; !rv && i < e->ipfe_narg; i++) { 5032 rv |= (state->is_sport == e->ipfe_arg0[i]) || 5033 (state->is_dport == e->ipfe_arg0[i]); 5034 } 5035 break; 5036 5037 case IPF_EXP_UDP_SPORT : 5038 case IPF_EXP_TCP_SPORT : 5039 for (i = 0; !rv && i < e->ipfe_narg; i++) { 5040 rv |= (state->is_sport == e->ipfe_arg0[i]); 5041 } 5042 break; 5043 5044 case IPF_EXP_UDP_DPORT : 5045 case IPF_EXP_TCP_DPORT : 5046 for (i = 0; !rv && i < e->ipfe_narg; i++) { 5047 rv |= (state->is_dport == e->ipfe_arg0[i]); 5048 } 5049 break; 5050 5051 case IPF_EXP_TCP_STATE : 5052 for (i = 0; !rv && i < e->ipfe_narg; i++) { 5053 rv |= (state->is_state[0] == e->ipfe_arg0[i]) || 5054 (state->is_state[1] == e->ipfe_arg0[i]); 5055 } 5056 break; 5057 5058 case IPF_EXP_IDLE_GT : 5059 rv |= (ticks - state->is_touched > e->ipfe_arg0[0]); 5060 break; 5061 } 5062 5063 /* 5064 * Factor in doing a negative match. 5065 */ 5066 rv ^= e->ipfe_not; 5067 5068 if (rv == 0) 5069 break; 5070 } 5071 5072 return rv; 5073 } 5074 5075 5076 /* ------------------------------------------------------------------------ */ 5077 /* Function: ipf_state_settimeout */ 5078 /* Returns: int 0 = success, else failure */ 5079 /* Parameters: softc(I) - pointer to main soft context */ 5080 /* t(I) - pointer to tuneable being changed */ 5081 /* p(I) - pointer to the new value */ 5082 /* */ 5083 /* Sets a timeout value for one of the many timeout queues. We find the */ 5084 /* correct queue using a somewhat manual process of comparing the timeout */ 5085 /* names for each specific value available and calling ipf_apply_timeout on */ 5086 /* that queue so that all of the items on it are updated accordingly. */ 5087 /* ------------------------------------------------------------------------ */ 5088 int 5089 ipf_state_settimeout(struct ipf_main_softc_s *softc, ipftuneable_t *t, 5090 ipftuneval_t *p) 5091 { 5092 ipf_state_softc_t *softs = softc->ipf_state_soft; 5093 5094 /* 5095 * In case there is nothing to do... 5096 */ 5097 if (*t->ipft_pint == p->ipftu_int) 5098 return 0; 5099 5100 if (!strncmp(t->ipft_name, "tcp_", 4)) 5101 return ipf_settimeout_tcp(t, p, softs->ipf_state_tcptq); 5102 5103 if (!strcmp(t->ipft_name, "udp_timeout")) { 5104 ipf_apply_timeout(&softs->ipf_state_udptq, p->ipftu_int); 5105 } else if (!strcmp(t->ipft_name, "udp_ack_timeout")) { 5106 ipf_apply_timeout(&softs->ipf_state_udpacktq, p->ipftu_int); 5107 } else if (!strcmp(t->ipft_name, "icmp_timeout")) { 5108 ipf_apply_timeout(&softs->ipf_state_icmptq, p->ipftu_int); 5109 } else if (!strcmp(t->ipft_name, "icmp_ack_timeout")) { 5110 ipf_apply_timeout(&softs->ipf_state_icmpacktq, p->ipftu_int); 5111 } else if (!strcmp(t->ipft_name, "ip_timeout")) { 5112 ipf_apply_timeout(&softs->ipf_state_iptq, p->ipftu_int); 5113 } else { 5114 IPFERROR(100034); 5115 return ESRCH; 5116 } 5117 5118 /* 5119 * Update the tuneable being set. 5120 */ 5121 *t->ipft_pint = p->ipftu_int; 5122 5123 return 0; 5124 } 5125 5126 5127 /* ------------------------------------------------------------------------ */ 5128 /* Function: ipf_state_rehash */ 5129 /* Returns: int 0 = success, else failure */ 5130 /* Parameters: softc(I) - pointer to main soft context */ 5131 /* t(I) - pointer to tuneable being changed */ 5132 /* p(I) - pointer to the new value */ 5133 /* */ 5134 /* To change the size of the state hash table at runtime, a new table has */ 5135 /* to be allocated and then all of the existing entries put in it, bumping */ 5136 /* up the bucketlength for it as we go along. */ 5137 /* ------------------------------------------------------------------------ */ 5138 int 5139 ipf_state_rehash(ipf_main_softc_t *softc, ipftuneable_t *t, ipftuneval_t *p) 5140 { 5141 ipf_state_softc_t *softs = softc->ipf_state_soft; 5142 ipstate_t **newtab, *is; 5143 u_int *bucketlens; 5144 u_int maxbucket; 5145 u_int newsize; 5146 u_int hv; 5147 int i; 5148 5149 newsize = p->ipftu_int; 5150 /* 5151 * In case there is nothing to do... 5152 */ 5153 if (newsize == softs->ipf_state_size) 5154 return 0; 5155 5156 KMALLOCS(newtab, ipstate_t **, newsize * sizeof(ipstate_t *)); 5157 if (newtab == NULL) { 5158 IPFERROR(100035); 5159 return ENOMEM; 5160 } 5161 5162 KMALLOCS(bucketlens, u_int *, newsize * sizeof(u_int)); 5163 if (bucketlens == NULL) { 5164 KFREES(newtab, newsize * sizeof(*softs->ipf_state_table)); 5165 IPFERROR(100036); 5166 return ENOMEM; 5167 } 5168 5169 for (maxbucket = 0, i = newsize; i > 0; i >>= 1) 5170 maxbucket++; 5171 maxbucket *= 2; 5172 5173 bzero((char *)newtab, newsize * sizeof(ipstate_t *)); 5174 bzero((char *)bucketlens, newsize * sizeof(u_int)); 5175 5176 WRITE_ENTER(&softc->ipf_state); 5177 5178 if (softs->ipf_state_table != NULL) { 5179 KFREES(softs->ipf_state_table, 5180 softs->ipf_state_size * sizeof(*softs->ipf_state_table)); 5181 } 5182 softs->ipf_state_table = newtab; 5183 5184 if (softs->ipf_state_stats.iss_bucketlen != NULL) { 5185 KFREES(softs->ipf_state_stats.iss_bucketlen, 5186 softs->ipf_state_size * sizeof(u_int)); 5187 } 5188 softs->ipf_state_stats.iss_bucketlen = bucketlens; 5189 softs->ipf_state_maxbucket = maxbucket; 5190 softs->ipf_state_size = newsize; 5191 5192 /* 5193 * Walk through the entire list of state table entries and put them 5194 * in the new state table, somewhere. Because we have a new table, 5195 * we need to restart the counter of how many chains are in use. 5196 */ 5197 softs->ipf_state_stats.iss_inuse = 0; 5198 for (is = softs->ipf_state_list; is != NULL; is = is->is_next) { 5199 is->is_hnext = NULL; 5200 is->is_phnext = NULL; 5201 hv = is->is_hv % softs->ipf_state_size; 5202 5203 if (softs->ipf_state_table[hv] != NULL) 5204 softs->ipf_state_table[hv]->is_phnext = &is->is_hnext; 5205 else 5206 softs->ipf_state_stats.iss_inuse++; 5207 is->is_phnext = softs->ipf_state_table + hv; 5208 is->is_hnext = softs->ipf_state_table[hv]; 5209 softs->ipf_state_table[hv] = is; 5210 softs->ipf_state_stats.iss_bucketlen[hv]++; 5211 } 5212 RWLOCK_EXIT(&softc->ipf_state); 5213 5214 return 0; 5215 } 5216 5217 5218 /* ------------------------------------------------------------------------ */ 5219 /* Function: ipf_state_add_tq */ 5220 /* Returns: ipftq_t * - NULL = failure, else pointer to new timeout */ 5221 /* queue */ 5222 /* Parameters: softc(I) - pointer to main soft context */ 5223 /* ttl(I) - pointer to the ttl for the new queue */ 5224 /* */ 5225 /* Request a pointer to a timeout queue that has a ttl as given by the */ 5226 /* value being passed in. The timeout queue is added tot the list of those */ 5227 /* used internally for stateful filtering. */ 5228 /* ------------------------------------------------------------------------ */ 5229 ipftq_t * 5230 ipf_state_add_tq(ipf_main_softc_t *softc, int ttl) 5231 { 5232 ipf_state_softc_t *softs = softc->ipf_state_soft; 5233 5234 return ipf_addtimeoutqueue(softc, &softs->ipf_state_usertq, ttl); 5235 } 5236 5237 5238 #ifndef _KERNEL 5239 /* 5240 * Display the built up state table rules and mapping entries. 5241 */ 5242 void 5243 ipf_state_dump(ipf_main_softc_t *softc, void *arg) 5244 { 5245 ipf_state_softc_t *softs = arg; 5246 ipstate_t *ips; 5247 5248 printf("List of active state sessions:\n"); 5249 for (ips = softs->ipf_state_list; ips != NULL; ) 5250 ips = printstate(ips, opts & (OPT_DEBUG|OPT_VERBOSE), 5251 softc->ipf_ticks); 5252 } 5253 #endif 5254