ip_state.c revision 287651
1/* $NetBSD: ip_state.c,v 1.4 2012/12/20 21:42:28 christos Exp $ */ 2 3/* 4 * Copyright (C) 2012 by Darren Reed. 5 * 6 * See the IPFILTER.LICENCE file for details on licencing. 7 * 8 * Copyright 2008 Sun Microsystems. 9 * 10 * $Id$ 11 */ 12#if defined(KERNEL) || defined(_KERNEL) 13# undef KERNEL 14# undef _KERNEL 15# define KERNEL 1 16# define _KERNEL 1 17#endif 18#include <sys/errno.h> 19#include <sys/types.h> 20#include <sys/param.h> 21#include <sys/file.h> 22#if defined(_KERNEL) && defined(__FreeBSD_version) && \ 23 (__FreeBSD_version >= 400000) && !defined(KLD_MODULE) 24#include "opt_inet6.h" 25#endif 26#if !defined(_KERNEL) && !defined(__KERNEL__) 27# include <stdio.h> 28# include <stdlib.h> 29# include <string.h> 30# define _KERNEL 31# ifdef __OpenBSD__ 32struct file; 33# endif 34# include <sys/uio.h> 35# undef _KERNEL 36#endif 37#if defined(_KERNEL) && (__FreeBSD_version >= 220000) 38# include <sys/filio.h> 39# include <sys/fcntl.h> 40#else 41# include <sys/ioctl.h> 42#endif 43#include <sys/time.h> 44#if !defined(linux) 45# include <sys/protosw.h> 46#endif 47#include <sys/socket.h> 48#if defined(_KERNEL) 49# include <sys/systm.h> 50# if !defined(__SVR4) && !defined(__svr4__) 51# include <sys/mbuf.h> 52# endif 53#endif 54#if defined(__SVR4) || defined(__svr4__) 55# include <sys/filio.h> 56# include <sys/byteorder.h> 57# ifdef _KERNEL 58# include <sys/dditypes.h> 59# endif 60# include <sys/stream.h> 61# include <sys/kmem.h> 62#endif 63 64#include <net/if.h> 65#ifdef sun 66# include <net/af.h> 67#endif 68#include <netinet/in.h> 69#include <netinet/in_systm.h> 70#include <netinet/ip.h> 71#include <netinet/tcp.h> 72#if !defined(__hpux) && !defined(linux) 73# include <netinet/tcp_fsm.h> 74#endif 75#include <netinet/udp.h> 76#include <netinet/ip_icmp.h> 77#if !defined(_KERNEL) 78# include "ipf.h" 79#endif 80#include "netinet/ip_compat.h" 81#include "netinet/ip_fil.h" 82#include "netinet/ip_nat.h" 83#include "netinet/ip_frag.h" 84#include "netinet/ip_state.h" 85#include "netinet/ip_proxy.h" 86#include "netinet/ip_lookup.h" 87#include "netinet/ip_dstlist.h" 88#include "netinet/ip_sync.h" 89#ifdef USE_INET6 90#include <netinet/icmp6.h> 91#endif 92#if FREEBSD_GE_REV(300000) 93# include <sys/malloc.h> 94# if defined(_KERNEL) && !defined(IPFILTER_LKM) 95# include <sys/libkern.h> 96# include <sys/systm.h> 97# endif 98#endif 99/* END OF INCLUDES */ 100 101 102#if !defined(lint) 103static const char sccsid[] = "@(#)ip_state.c 1.8 6/5/96 (C) 1993-2000 Darren Reed"; 104static const char rcsid[] = "@(#)$Id$"; 105#endif 106 107 108static ipftuneable_t ipf_state_tuneables[] = { 109 { { (void *)offsetof(ipf_state_softc_t, ipf_state_max) }, 110 "state_max", 1, 0x7fffffff, 111 stsizeof(ipf_state_softc_t, ipf_state_max), 112 0, NULL, NULL }, 113 { { (void *)offsetof(ipf_state_softc_t, ipf_state_size) }, 114 "state_size", 1, 0x7fffffff, 115 stsizeof(ipf_state_softc_t, ipf_state_size), 116 0, NULL, ipf_state_rehash }, 117 { { (void *)offsetof(ipf_state_softc_t, ipf_state_lock) }, 118 "state_lock", 0, 1, 119 stsizeof(ipf_state_softc_t, ipf_state_lock), 120 IPFT_RDONLY, NULL, NULL }, 121 { { (void *)offsetof(ipf_state_softc_t, ipf_state_maxbucket) }, 122 "state_maxbucket", 1, 0x7fffffff, 123 stsizeof(ipf_state_softc_t, ipf_state_maxbucket), 124 0, NULL, NULL }, 125 { { (void *)offsetof(ipf_state_softc_t, ipf_state_logging) }, 126 "state_logging",0, 1, 127 stsizeof(ipf_state_softc_t, ipf_state_logging), 128 0, NULL, NULL }, 129 { { (void *)offsetof(ipf_state_softc_t, ipf_state_wm_high) }, 130 "state_wm_high",2, 100, 131 stsizeof(ipf_state_softc_t, ipf_state_wm_high), 132 0, NULL, NULL }, 133 { { (void *)offsetof(ipf_state_softc_t, ipf_state_wm_low) }, 134 "state_wm_low", 1, 99, 135 stsizeof(ipf_state_softc_t, ipf_state_wm_low), 136 0, NULL, NULL }, 137 { { (void *)offsetof(ipf_state_softc_t, ipf_state_wm_freq) }, 138 "state_wm_freq",2, 999999, 139 stsizeof(ipf_state_softc_t, ipf_state_wm_freq), 140 0, NULL, NULL }, 141 { { NULL }, 142 NULL, 0, 0, 143 0, 144 0, NULL, NULL } 145}; 146 147#define SINCL(x) ATOMIC_INCL(softs->x) 148#define SBUMP(x) (softs->x)++ 149#define SBUMPD(x, y) do { (softs->x.y)++; DT(y); } while (0) 150#define SBUMPDX(x, y, z)do { (softs->x.y)++; DT(z); } while (0) 151 152#ifdef USE_INET6 153static ipstate_t *ipf_checkicmp6matchingstate __P((fr_info_t *)); 154#endif 155static int ipf_allowstateicmp __P((fr_info_t *, ipstate_t *, i6addr_t *)); 156static ipstate_t *ipf_matchsrcdst __P((fr_info_t *, ipstate_t *, i6addr_t *, 157 i6addr_t *, tcphdr_t *, u_32_t)); 158static ipstate_t *ipf_checkicmpmatchingstate __P((fr_info_t *)); 159static int ipf_state_flush_entry __P((ipf_main_softc_t *, void *)); 160static ips_stat_t *ipf_state_stats __P((ipf_main_softc_t *)); 161static int ipf_state_del __P((ipf_main_softc_t *, ipstate_t *, int)); 162static int ipf_state_remove __P((ipf_main_softc_t *, caddr_t)); 163static int ipf_state_match __P((ipstate_t *is1, ipstate_t *is2)); 164static int ipf_state_matchaddresses __P((ipstate_t *is1, ipstate_t *is2)); 165static int ipf_state_matchipv4addrs __P((ipstate_t *is1, ipstate_t *is2)); 166static int ipf_state_matchipv6addrs __P((ipstate_t *is1, ipstate_t *is2)); 167static int ipf_state_matchisps __P((ipstate_t *is1, ipstate_t *is2)); 168static int ipf_state_matchports __P((udpinfo_t *is1, udpinfo_t *is2)); 169static int ipf_state_matcharray __P((ipstate_t *, int *, u_long)); 170static void ipf_ipsmove __P((ipf_state_softc_t *, ipstate_t *, u_int)); 171static int ipf_state_tcp __P((ipf_main_softc_t *, ipf_state_softc_t *, 172 fr_info_t *, tcphdr_t *, ipstate_t *)); 173static int ipf_tcpoptions __P((ipf_state_softc_t *, fr_info_t *, 174 tcphdr_t *, tcpdata_t *)); 175static ipstate_t *ipf_state_clone __P((fr_info_t *, tcphdr_t *, ipstate_t *)); 176static void ipf_fixinisn __P((fr_info_t *, ipstate_t *)); 177static void ipf_fixoutisn __P((fr_info_t *, ipstate_t *)); 178static void ipf_checknewisn __P((fr_info_t *, ipstate_t *)); 179static int ipf_state_iter __P((ipf_main_softc_t *, ipftoken_t *, 180 ipfgeniter_t *, ipfobj_t *)); 181static int ipf_state_gettable __P((ipf_main_softc_t *, ipf_state_softc_t *, 182 char *)); 183static int ipf_state_tcpinwindow __P((struct fr_info *, struct tcpdata *, 184 struct tcpdata *, tcphdr_t *, int)); 185 186static int ipf_state_getent __P((ipf_main_softc_t *, ipf_state_softc_t *, 187 caddr_t)); 188static int ipf_state_putent __P((ipf_main_softc_t *, ipf_state_softc_t *, 189 caddr_t)); 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/* ------------------------------------------------------------------------ */ 205int 206ipf_state_main_load() 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/* ------------------------------------------------------------------------ */ 220int 221ipf_state_main_unload() 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/* ------------------------------------------------------------------------ */ 235void * 236ipf_state_soft_create(softc) 237 ipf_main_softc_t *softc; 238{ 239 ipf_state_softc_t *softs; 240 241 KMALLOC(softs, ipf_state_softc_t *); 242 if (softs == NULL) 243 return NULL; 244 245 bzero((char *)softs, sizeof(*softs)); 246 247 softs->ipf_state_tune = ipf_tune_array_copy(softs, 248 sizeof(ipf_state_tuneables), 249 ipf_state_tuneables); 250 if (softs->ipf_state_tune == NULL) { 251 ipf_state_soft_destroy(softc, softs); 252 return NULL; 253 } 254 if (ipf_tune_array_link(softc, softs->ipf_state_tune) == -1) { 255 ipf_state_soft_destroy(softc, softs); 256 return NULL; 257 } 258 259#ifdef IPFILTER_LOG 260 softs->ipf_state_logging = 1; 261#else 262 softs->ipf_state_logging = 0; 263#endif 264 softs->ipf_state_size = IPSTATE_SIZE, 265 softs->ipf_state_maxbucket = 0; 266 softs->ipf_state_wm_freq = IPF_TTLVAL(10); 267 softs->ipf_state_max = IPSTATE_MAX; 268 softs->ipf_state_wm_last = 0; 269 softs->ipf_state_wm_high = 99; 270 softs->ipf_state_wm_low = 90; 271 softs->ipf_state_inited = 0; 272 softs->ipf_state_lock = 0; 273 softs->ipf_state_doflush = 0; 274 275 return softs; 276} 277 278 279/* ------------------------------------------------------------------------ */ 280/* Function: ipf_state_soft_destroy */ 281/* Returns: Nil */ 282/* Parameters: softc(I) - pointer to soft context main structure */ 283/* arg(I) - pointer to local context to use */ 284/* */ 285/* Undo only what we did in soft create: unlink and free the tunables and */ 286/* free the soft context structure itself. */ 287/* ------------------------------------------------------------------------ */ 288void 289ipf_state_soft_destroy(softc, arg) 290 ipf_main_softc_t *softc; 291 void *arg; 292{ 293 ipf_state_softc_t *softs = arg; 294 295 if (softs->ipf_state_tune != NULL) { 296 ipf_tune_array_unlink(softc, softs->ipf_state_tune); 297 KFREES(softs->ipf_state_tune, sizeof(ipf_state_tuneables)); 298 softs->ipf_state_tune = NULL; 299 } 300 301 KFREE(softs); 302} 303 304 305/* ------------------------------------------------------------------------ */ 306/* Function: ipf_state_soft_init */ 307/* Returns: int - 0 == success, -1 == failure */ 308/* Parameters: softc(I) - pointer to soft context main structure */ 309/* arg(I) - pointer to local context to use */ 310/* */ 311/* Initialise the state soft context structure so it is ready for use. */ 312/* This involves: */ 313/* - allocating a hash table and zero'ing it out */ 314/* - building a secondary table of seeds for double hashing to make it more */ 315/* difficult to attempt to attack the hash table itself (for DoS) */ 316/* - initialise all of the timeout queues, including a table for TCP, some */ 317/* pairs of query/response for UDP and other IP protocols (typically the */ 318/* reply queue has a shorter timeout than the query) */ 319/* ------------------------------------------------------------------------ */ 320int 321ipf_state_soft_init(softc, arg) 322 ipf_main_softc_t *softc; 323 void *arg; 324{ 325 ipf_state_softc_t *softs = arg; 326 int i; 327 328 KMALLOCS(softs->ipf_state_table, 329 ipstate_t **, softs->ipf_state_size * sizeof(ipstate_t *)); 330 if (softs->ipf_state_table == NULL) 331 return -1; 332 333 bzero((char *)softs->ipf_state_table, 334 softs->ipf_state_size * sizeof(ipstate_t *)); 335 336 KMALLOCS(softs->ipf_state_seed, u_long *, 337 softs->ipf_state_size * sizeof(*softs->ipf_state_seed)); 338 if (softs->ipf_state_seed == NULL) 339 return -2; 340 341 for (i = 0; i < softs->ipf_state_size; i++) { 342 /* 343 * XXX - ipf_state_seed[X] should be a random number of sorts. 344 */ 345#if FREEBSD_GE_REV(400000) 346 softs->ipf_state_seed[i] = arc4random(); 347#else 348 softs->ipf_state_seed[i] = ((u_long)softs->ipf_state_seed + i) * 349 softs->ipf_state_size; 350 softs->ipf_state_seed[i] ^= 0xa5a55a5a; 351 softs->ipf_state_seed[i] *= (u_long)softs->ipf_state_seed; 352 softs->ipf_state_seed[i] ^= 0x5a5aa5a5; 353 softs->ipf_state_seed[i] *= softs->ipf_state_max; 354#endif 355 } 356 357 KMALLOCS(softs->ipf_state_stats.iss_bucketlen, u_int *, 358 softs->ipf_state_size * sizeof(u_int)); 359 if (softs->ipf_state_stats.iss_bucketlen == NULL) 360 return -3; 361 362 bzero((char *)softs->ipf_state_stats.iss_bucketlen, 363 softs->ipf_state_size * sizeof(u_int)); 364 365 if (softs->ipf_state_maxbucket == 0) { 366 for (i = softs->ipf_state_size; i > 0; i >>= 1) 367 softs->ipf_state_maxbucket++; 368 softs->ipf_state_maxbucket *= 2; 369 } 370 371 ipf_sttab_init(softc, softs->ipf_state_tcptq); 372 softs->ipf_state_stats.iss_tcptab = softs->ipf_state_tcptq; 373 softs->ipf_state_tcptq[IPF_TCP_NSTATES - 1].ifq_next = 374 &softs->ipf_state_udptq; 375 376 IPFTQ_INIT(&softs->ipf_state_udptq, softc->ipf_udptimeout, 377 "ipftq udp tab"); 378 softs->ipf_state_udptq.ifq_next = &softs->ipf_state_udpacktq; 379 380 IPFTQ_INIT(&softs->ipf_state_udpacktq, softc->ipf_udpacktimeout, 381 "ipftq udpack tab"); 382 softs->ipf_state_udpacktq.ifq_next = &softs->ipf_state_icmptq; 383 384 IPFTQ_INIT(&softs->ipf_state_icmptq, softc->ipf_icmptimeout, 385 "ipftq icmp tab"); 386 softs->ipf_state_icmptq.ifq_next = &softs->ipf_state_icmpacktq; 387 388 IPFTQ_INIT(&softs->ipf_state_icmpacktq, softc->ipf_icmpacktimeout, 389 "ipftq icmpack tab"); 390 softs->ipf_state_icmpacktq.ifq_next = &softs->ipf_state_iptq; 391 392 IPFTQ_INIT(&softs->ipf_state_iptq, softc->ipf_iptimeout, 393 "ipftq iptimeout tab"); 394 softs->ipf_state_iptq.ifq_next = &softs->ipf_state_pending; 395 396 IPFTQ_INIT(&softs->ipf_state_pending, IPF_HZ_DIVIDE, "ipftq pending"); 397 softs->ipf_state_pending.ifq_next = &softs->ipf_state_deletetq; 398 399 IPFTQ_INIT(&softs->ipf_state_deletetq, 1, "ipftq delete"); 400 softs->ipf_state_deletetq.ifq_next = NULL; 401 402 MUTEX_INIT(&softs->ipf_stinsert, "ipf state insert mutex"); 403 404 405 softs->ipf_state_wm_last = softc->ipf_ticks; 406 softs->ipf_state_inited = 1; 407 408 return 0; 409} 410 411 412/* ------------------------------------------------------------------------ */ 413/* Function: ipf_state_soft_fini */ 414/* Returns: int - 0 = success, -1 = failure */ 415/* Parameters: softc(I) - pointer to soft context main structure */ 416/* arg(I) - pointer to local context to use */ 417/* */ 418/* Release and destroy any resources acquired or initialised so that */ 419/* IPFilter can be unloaded or re-initialised. */ 420/* ------------------------------------------------------------------------ */ 421int 422ipf_state_soft_fini(softc, arg) 423 ipf_main_softc_t *softc; 424 void *arg; 425{ 426 ipf_state_softc_t *softs = arg; 427 ipftq_t *ifq, *ifqnext; 428 ipstate_t *is; 429 430 while ((is = softs->ipf_state_list) != NULL) 431 ipf_state_del(softc, is, ISL_UNLOAD); 432 433 /* 434 * Proxy timeout queues are not cleaned here because although they 435 * exist on the state list, appr_unload is called after 436 * ipf_state_unload and the proxies actually are responsible for them 437 * being created. Should the proxy timeouts have their own list? 438 * There's no real justification as this is the only complication. 439 */ 440 for (ifq = softs->ipf_state_usertq; ifq != NULL; ifq = ifqnext) { 441 ifqnext = ifq->ifq_next; 442 443 if (ipf_deletetimeoutqueue(ifq) == 0) 444 ipf_freetimeoutqueue(softc, ifq); 445 } 446 447 softs->ipf_state_stats.iss_inuse = 0; 448 softs->ipf_state_stats.iss_active = 0; 449 450 if (softs->ipf_state_inited == 1) { 451 softs->ipf_state_inited = 0; 452 ipf_sttab_destroy(softs->ipf_state_tcptq); 453 MUTEX_DESTROY(&softs->ipf_state_udptq.ifq_lock); 454 MUTEX_DESTROY(&softs->ipf_state_icmptq.ifq_lock); 455 MUTEX_DESTROY(&softs->ipf_state_udpacktq.ifq_lock); 456 MUTEX_DESTROY(&softs->ipf_state_icmpacktq.ifq_lock); 457 MUTEX_DESTROY(&softs->ipf_state_iptq.ifq_lock); 458 MUTEX_DESTROY(&softs->ipf_state_deletetq.ifq_lock); 459 MUTEX_DESTROY(&softs->ipf_state_pending.ifq_lock); 460 MUTEX_DESTROY(&softs->ipf_stinsert); 461 } 462 463 if (softs->ipf_state_table != NULL) { 464 KFREES(softs->ipf_state_table, 465 softs->ipf_state_size * sizeof(*softs->ipf_state_table)); 466 softs->ipf_state_table = NULL; 467 } 468 469 if (softs->ipf_state_seed != NULL) { 470 KFREES(softs->ipf_state_seed, 471 softs->ipf_state_size * sizeof(*softs->ipf_state_seed)); 472 softs->ipf_state_seed = NULL; 473 } 474 475 if (softs->ipf_state_stats.iss_bucketlen != NULL) { 476 KFREES(softs->ipf_state_stats.iss_bucketlen, 477 softs->ipf_state_size * sizeof(u_int)); 478 softs->ipf_state_stats.iss_bucketlen = NULL; 479 } 480 481 return 0; 482} 483 484 485/* ------------------------------------------------------------------------ */ 486/* Function: ipf_state_set_lock */ 487/* Returns: Nil */ 488/* Parameters: arg(I) - pointer to local context to use */ 489/* tmp(I) - new value for lock */ 490/* */ 491/* Stub function that allows for external manipulation of ipf_state_lock */ 492/* ------------------------------------------------------------------------ */ 493void 494ipf_state_setlock(arg, tmp) 495 void *arg; 496 int tmp; 497{ 498 ipf_state_softc_t *softs = arg; 499 500 softs->ipf_state_lock = tmp; 501} 502 503 504/* ------------------------------------------------------------------------ */ 505/* Function: ipf_state_stats */ 506/* Returns: ips_state_t* - pointer to state stats structure */ 507/* Parameters: softc(I) - pointer to soft context main structure */ 508/* */ 509/* Put all the current numbers and pointers into a single struct and return */ 510/* a pointer to it. */ 511/* ------------------------------------------------------------------------ */ 512static ips_stat_t * 513ipf_state_stats(softc) 514 ipf_main_softc_t *softc; 515{ 516 ipf_state_softc_t *softs = softc->ipf_state_soft; 517 ips_stat_t *issp = &softs->ipf_state_stats; 518 519 issp->iss_state_size = softs->ipf_state_size; 520 issp->iss_state_max = softs->ipf_state_max; 521 issp->iss_table = softs->ipf_state_table; 522 issp->iss_list = softs->ipf_state_list; 523 issp->iss_ticks = softc->ipf_ticks; 524 525#ifdef IPFILTER_LOGGING 526 issp->iss_log_ok = ipf_log_logok(softc, IPF_LOGSTATE); 527 issp->iss_log_fail = ipf_log_failures(softc, IPF_LOGSTATE); 528#else 529 issp->iss_log_ok = 0; 530 issp->iss_log_fail = 0; 531#endif 532 return issp; 533} 534 535/* ------------------------------------------------------------------------ */ 536/* Function: ipf_state_remove */ 537/* Returns: int - 0 == success, != 0 == failure */ 538/* Parameters: softc(I) - pointer to soft context main structure */ 539/* data(I) - pointer to state structure to delete from table */ 540/* */ 541/* Search for a state structure that matches the one passed, according to */ 542/* the IP addresses and other protocol specific information. */ 543/* ------------------------------------------------------------------------ */ 544static int 545ipf_state_remove(softc, data) 546 ipf_main_softc_t *softc; 547 caddr_t data; 548{ 549 ipf_state_softc_t *softs = softc->ipf_state_soft; 550 ipstate_t *sp, st; 551 int error; 552 553 sp = &st; 554 error = ipf_inobj(softc, data, NULL, &st, IPFOBJ_IPSTATE); 555 if (error) 556 return EFAULT; 557 558 WRITE_ENTER(&softc->ipf_state); 559 for (sp = softs->ipf_state_list; sp; sp = sp->is_next) 560 if ((sp->is_p == st.is_p) && (sp->is_v == st.is_v) && 561 !bcmp((caddr_t)&sp->is_src, (caddr_t)&st.is_src, 562 sizeof(st.is_src)) && 563 !bcmp((caddr_t)&sp->is_dst, (caddr_t)&st.is_dst, 564 sizeof(st.is_dst)) && 565 !bcmp((caddr_t)&sp->is_ps, (caddr_t)&st.is_ps, 566 sizeof(st.is_ps))) { 567 ipf_state_del(softc, sp, ISL_REMOVE); 568 RWLOCK_EXIT(&softc->ipf_state); 569 return 0; 570 } 571 RWLOCK_EXIT(&softc->ipf_state); 572 573 IPFERROR(100001); 574 return ESRCH; 575} 576 577 578/* ------------------------------------------------------------------------ */ 579/* Function: ipf_state_ioctl */ 580/* Returns: int - 0 == success, != 0 == failure */ 581/* Parameters: softc(I) - pointer to soft context main structure */ 582/* data(I) - pointer to ioctl data */ 583/* cmd(I) - ioctl command integer */ 584/* mode(I) - file mode bits used with open */ 585/* uid(I) - uid of process making the ioctl call */ 586/* ctx(I) - pointer specific to context of the call */ 587/* */ 588/* Processes an ioctl call made to operate on the IP Filter state device. */ 589/* ------------------------------------------------------------------------ */ 590int 591ipf_state_ioctl(softc, data, cmd, mode, uid, ctx) 592 ipf_main_softc_t *softc; 593 caddr_t data; 594 ioctlcmd_t cmd; 595 int mode, uid; 596 void *ctx; 597{ 598 ipf_state_softc_t *softs = softc->ipf_state_soft; 599 int arg, ret, error = 0; 600 SPL_INT(s); 601 602 switch (cmd) 603 { 604 /* 605 * Delete an entry from the state table. 606 */ 607 case SIOCDELST : 608 error = ipf_state_remove(softc, data); 609 break; 610 611 /* 612 * Flush the state table 613 */ 614 case SIOCIPFFL : 615 error = BCOPYIN(data, &arg, sizeof(arg)); 616 if (error != 0) { 617 IPFERROR(100002); 618 error = EFAULT; 619 620 } else { 621 WRITE_ENTER(&softc->ipf_state); 622 ret = ipf_state_flush(softc, arg, 4); 623 RWLOCK_EXIT(&softc->ipf_state); 624 625 error = BCOPYOUT(&ret, data, sizeof(ret)); 626 if (error != 0) { 627 IPFERROR(100003); 628 error = EFAULT; 629 } 630 } 631 break; 632 633#ifdef USE_INET6 634 case SIOCIPFL6 : 635 error = BCOPYIN(data, &arg, sizeof(arg)); 636 if (error != 0) { 637 IPFERROR(100004); 638 error = EFAULT; 639 640 } else { 641 WRITE_ENTER(&softc->ipf_state); 642 ret = ipf_state_flush(softc, arg, 6); 643 RWLOCK_EXIT(&softc->ipf_state); 644 645 error = BCOPYOUT(&ret, data, sizeof(ret)); 646 if (error != 0) { 647 IPFERROR(100005); 648 error = EFAULT; 649 } 650 } 651 break; 652#endif 653 654 case SIOCMATCHFLUSH : 655 WRITE_ENTER(&softc->ipf_state); 656 error = ipf_state_matchflush(softc, data); 657 RWLOCK_EXIT(&softc->ipf_state); 658 break; 659 660#ifdef IPFILTER_LOG 661 /* 662 * Flush the state log. 663 */ 664 case SIOCIPFFB : 665 if (!(mode & FWRITE)) { 666 IPFERROR(100008); 667 error = EPERM; 668 } else { 669 int tmp; 670 671 tmp = ipf_log_clear(softc, IPL_LOGSTATE); 672 error = BCOPYOUT(&tmp, data, sizeof(tmp)); 673 if (error != 0) { 674 IPFERROR(100009); 675 error = EFAULT; 676 } 677 } 678 break; 679 680 /* 681 * Turn logging of state information on/off. 682 */ 683 case SIOCSETLG : 684 if (!(mode & FWRITE)) { 685 IPFERROR(100010); 686 error = EPERM; 687 } else { 688 error = BCOPYIN(data, &softs->ipf_state_logging, 689 sizeof(softs->ipf_state_logging)); 690 if (error != 0) { 691 IPFERROR(100011); 692 error = EFAULT; 693 } 694 } 695 break; 696 697 /* 698 * Return the current state of logging. 699 */ 700 case SIOCGETLG : 701 error = BCOPYOUT(&softs->ipf_state_logging, data, 702 sizeof(softs->ipf_state_logging)); 703 if (error != 0) { 704 IPFERROR(100012); 705 error = EFAULT; 706 } 707 break; 708 709 /* 710 * Return the number of bytes currently waiting to be read. 711 */ 712 case FIONREAD : 713 arg = ipf_log_bytesused(softc, IPL_LOGSTATE); 714 error = BCOPYOUT(&arg, data, sizeof(arg)); 715 if (error != 0) { 716 IPFERROR(100013); 717 error = EFAULT; 718 } 719 break; 720#endif 721 722 /* 723 * Get the current state statistics. 724 */ 725 case SIOCGETFS : 726 error = ipf_outobj(softc, data, ipf_state_stats(softc), 727 IPFOBJ_STATESTAT); 728 break; 729 730 /* 731 * Lock/Unlock the state table. (Locking prevents any changes, which 732 * means no packets match). 733 */ 734 case SIOCSTLCK : 735 if (!(mode & FWRITE)) { 736 IPFERROR(100014); 737 error = EPERM; 738 } else { 739 error = ipf_lock(data, &softs->ipf_state_lock); 740 } 741 break; 742 743 /* 744 * Add an entry to the current state table. 745 */ 746 case SIOCSTPUT : 747 if (!softs->ipf_state_lock || !(mode &FWRITE)) { 748 IPFERROR(100015); 749 error = EACCES; 750 break; 751 } 752 error = ipf_state_putent(softc, softs, data); 753 break; 754 755 /* 756 * Get a state table entry. 757 */ 758 case SIOCSTGET : 759 if (!softs->ipf_state_lock) { 760 IPFERROR(100016); 761 error = EACCES; 762 break; 763 } 764 error = ipf_state_getent(softc, softs, data); 765 break; 766 767 /* 768 * Return a copy of the hash table bucket lengths 769 */ 770 case SIOCSTAT1 : 771 error = BCOPYOUT(softs->ipf_state_stats.iss_bucketlen, data, 772 softs->ipf_state_size * sizeof(u_int)); 773 if (error != 0) { 774 IPFERROR(100017); 775 error = EFAULT; 776 } 777 break; 778 779 case SIOCGENITER : 780 { 781 ipftoken_t *token; 782 ipfgeniter_t iter; 783 ipfobj_t obj; 784 785 error = ipf_inobj(softc, data, &obj, &iter, IPFOBJ_GENITER); 786 if (error != 0) 787 break; 788 789 SPL_SCHED(s); 790 token = ipf_token_find(softc, IPFGENITER_STATE, uid, ctx); 791 if (token != NULL) { 792 error = ipf_state_iter(softc, token, &iter, &obj); 793 WRITE_ENTER(&softc->ipf_tokens); 794 ipf_token_deref(softc, token); 795 RWLOCK_EXIT(&softc->ipf_tokens); 796 } else { 797 IPFERROR(100018); 798 error = ESRCH; 799 } 800 SPL_X(s); 801 break; 802 } 803 804 case SIOCGTABL : 805 error = ipf_state_gettable(softc, softs, data); 806 break; 807 808 case SIOCIPFDELTOK : 809 error = BCOPYIN(data, &arg, sizeof(arg)); 810 if (error != 0) { 811 IPFERROR(100019); 812 error = EFAULT; 813 } else { 814 SPL_SCHED(s); 815 error = ipf_token_del(softc, arg, uid, ctx); 816 SPL_X(s); 817 } 818 break; 819 820 case SIOCGTQTAB : 821 error = ipf_outobj(softc, data, softs->ipf_state_tcptq, 822 IPFOBJ_STATETQTAB); 823 break; 824 825 default : 826 IPFERROR(100020); 827 error = EINVAL; 828 break; 829 } 830 return error; 831} 832 833 834/* ------------------------------------------------------------------------ */ 835/* Function: ipf_state_getent */ 836/* Returns: int - 0 == success, != 0 == failure */ 837/* Parameters: softc(I) - pointer to soft context main structure */ 838/* softs(I) - pointer to state context structure */ 839/* data(I) - pointer to state structure to retrieve from table*/ 840/* */ 841/* Copy out state information from the kernel to a user space process. If */ 842/* there is a filter rule associated with the state entry, copy that out */ 843/* as well. The entry to copy out is taken from the value of "ips_next" in */ 844/* the struct passed in and if not null and not found in the list of current*/ 845/* state entries, the retrieval fails. */ 846/* ------------------------------------------------------------------------ */ 847static int 848ipf_state_getent(softc, softs, data) 849 ipf_main_softc_t *softc; 850 ipf_state_softc_t *softs; 851 caddr_t data; 852{ 853 ipstate_t *is, *isn; 854 ipstate_save_t ips; 855 int error; 856 857 error = ipf_inobj(softc, data, NULL, &ips, IPFOBJ_STATESAVE); 858 if (error) 859 return EFAULT; 860 861 READ_ENTER(&softc->ipf_state); 862 isn = ips.ips_next; 863 if (isn == NULL) { 864 isn = softs->ipf_state_list; 865 if (isn == NULL) { 866 if (ips.ips_next == NULL) { 867 RWLOCK_EXIT(&softc->ipf_state); 868 IPFERROR(100021); 869 return ENOENT; 870 } 871 return 0; 872 } 873 } else { 874 /* 875 * Make sure the pointer we're copying from exists in the 876 * current list of entries. Security precaution to prevent 877 * copying of random kernel data. 878 */ 879 for (is = softs->ipf_state_list; is; is = is->is_next) 880 if (is == isn) 881 break; 882 if (!is) { 883 RWLOCK_EXIT(&softc->ipf_state); 884 IPFERROR(100022); 885 return ESRCH; 886 } 887 } 888 ips.ips_next = isn->is_next; 889 bcopy((char *)isn, (char *)&ips.ips_is, sizeof(ips.ips_is)); 890 ips.ips_rule = isn->is_rule; 891 if (isn->is_rule != NULL) 892 bcopy((char *)isn->is_rule, (char *)&ips.ips_fr, 893 sizeof(ips.ips_fr)); 894 RWLOCK_EXIT(&softc->ipf_state); 895 error = ipf_outobj(softc, data, &ips, IPFOBJ_STATESAVE); 896 return error; 897} 898 899 900/* ------------------------------------------------------------------------ */ 901/* Function: ipf_state_putent */ 902/* Returns: int - 0 == success, != 0 == failure */ 903/* Parameters: softc(I) - pointer to soft context main structure */ 904/* softs(I) - pointer to state context structure */ 905/* data(I) - pointer to state information struct */ 906/* */ 907/* This function implements the SIOCSTPUT ioctl: insert a state entry into */ 908/* the state table. If the state info. includes a pointer to a filter rule */ 909/* then also add in an orphaned rule (will not show up in any "ipfstat -io" */ 910/* output. */ 911/* ------------------------------------------------------------------------ */ 912int 913ipf_state_putent(softc, softs, data) 914 ipf_main_softc_t *softc; 915 ipf_state_softc_t *softs; 916 caddr_t data; 917{ 918 ipstate_t *is, *isn; 919 ipstate_save_t ips; 920 int error, out, i; 921 frentry_t *fr; 922 char *name; 923 924 error = ipf_inobj(softc, data, NULL, &ips, IPFOBJ_STATESAVE); 925 if (error != 0) 926 return error; 927 928 KMALLOC(isn, ipstate_t *); 929 if (isn == NULL) { 930 IPFERROR(100023); 931 return ENOMEM; 932 } 933 934 bcopy((char *)&ips.ips_is, (char *)isn, sizeof(*isn)); 935 bzero((char *)isn, offsetof(struct ipstate, is_pkts)); 936 isn->is_sti.tqe_pnext = NULL; 937 isn->is_sti.tqe_next = NULL; 938 isn->is_sti.tqe_ifq = NULL; 939 isn->is_sti.tqe_parent = isn; 940 isn->is_ifp[0] = NULL; 941 isn->is_ifp[1] = NULL; 942 isn->is_ifp[2] = NULL; 943 isn->is_ifp[3] = NULL; 944 isn->is_sync = NULL; 945 fr = ips.ips_rule; 946 947 if (fr == NULL) { 948 int inserr; 949 950 READ_ENTER(&softc->ipf_state); 951 inserr = ipf_state_insert(softc, isn, 0); 952 MUTEX_EXIT(&isn->is_lock); 953 RWLOCK_EXIT(&softc->ipf_state); 954 955 return inserr; 956 } 957 958 if (isn->is_flags & SI_NEWFR) { 959 KMALLOC(fr, frentry_t *); 960 if (fr == NULL) { 961 KFREE(isn); 962 IPFERROR(100024); 963 return ENOMEM; 964 } 965 bcopy((char *)&ips.ips_fr, (char *)fr, sizeof(*fr)); 966 out = fr->fr_flags & FR_OUTQUE ? 1 : 0; 967 isn->is_rule = fr; 968 ips.ips_is.is_rule = fr; 969 MUTEX_NUKE(&fr->fr_lock); 970 MUTEX_INIT(&fr->fr_lock, "state filter rule lock"); 971 972 /* 973 * Look up all the interface names in the rule. 974 */ 975 for (i = 0; i < 4; i++) { 976 if (fr->fr_ifnames[i] == -1) { 977 fr->fr_ifas[i] = NULL; 978 continue; 979 } 980 name = fr->fr_names + fr->fr_ifnames[i]; 981 fr->fr_ifas[i] = ipf_resolvenic(softc, name, 982 fr->fr_family); 983 } 984 985 for (i = 0; i < 4; i++) { 986 name = isn->is_ifname[i]; 987 isn->is_ifp[i] = ipf_resolvenic(softc, name, 988 isn->is_v); 989 } 990 991 fr->fr_ref = 0; 992 fr->fr_dsize = 0; 993 fr->fr_data = NULL; 994 fr->fr_type = FR_T_NONE; 995 996 (void) ipf_resolvedest(softc, fr->fr_names, &fr->fr_tifs[0], 997 fr->fr_family); 998 (void) ipf_resolvedest(softc, fr->fr_names, &fr->fr_tifs[1], 999 fr->fr_family); 1000 (void) ipf_resolvedest(softc, fr->fr_names, &fr->fr_dif, 1001 fr->fr_family); 1002 1003 /* 1004 * send a copy back to userland of what we ended up 1005 * to allow for verification. 1006 */ 1007 error = ipf_outobj(softc, data, &ips, IPFOBJ_STATESAVE); 1008 if (error != 0) { 1009 KFREE(isn); 1010 MUTEX_DESTROY(&fr->fr_lock); 1011 KFREE(fr); 1012 IPFERROR(100025); 1013 return EFAULT; 1014 } 1015 READ_ENTER(&softc->ipf_state); 1016 error = ipf_state_insert(softc, isn, 0); 1017 MUTEX_EXIT(&isn->is_lock); 1018 RWLOCK_EXIT(&softc->ipf_state); 1019 1020 } else { 1021 READ_ENTER(&softc->ipf_state); 1022 for (is = softs->ipf_state_list; is; is = is->is_next) 1023 if (is->is_rule == fr) { 1024 error = ipf_state_insert(softc, isn, 0); 1025 MUTEX_EXIT(&isn->is_lock); 1026 break; 1027 } 1028 1029 if (is == NULL) { 1030 KFREE(isn); 1031 isn = NULL; 1032 } 1033 RWLOCK_EXIT(&softc->ipf_state); 1034 1035 if (isn == NULL) { 1036 IPFERROR(100033); 1037 error = ESRCH; 1038 } 1039 } 1040 1041 return error; 1042} 1043 1044 1045/* ------------------------------------------------------------------------ */ 1046/* Function: ipf_state_insert */ 1047/* Returns: int - 0 == success, -1 == failure */ 1048/* Parameters: softc(I) - pointer to soft context main structure */ 1049/* Parameters: is(I) - pointer to state structure */ 1050/* rev(I) - flag indicating direction of packet */ 1051/* */ 1052/* Inserts a state structure into the hash table (for lookups) and the list */ 1053/* of state entries (for enumeration). Resolves all of the interface names */ 1054/* to pointers and adjusts running stats for the hash table as appropriate. */ 1055/* */ 1056/* This function can fail if the filter rule has had a population policy of */ 1057/* IP addresses used with stateful filtering assigned to it. */ 1058/* */ 1059/* Locking: it is assumed that some kind of lock on ipf_state is held. */ 1060/* Exits with is_lock initialised and held - *EVEN IF ERROR*. */ 1061/* ------------------------------------------------------------------------ */ 1062int 1063ipf_state_insert(softc, is, rev) 1064 ipf_main_softc_t *softc; 1065 ipstate_t *is; 1066 int rev; 1067{ 1068 ipf_state_softc_t *softs = softc->ipf_state_soft; 1069 frentry_t *fr; 1070 u_int hv; 1071 int i; 1072 1073 /* 1074 * Look up all the interface names in the state entry. 1075 */ 1076 for (i = 0; i < 4; i++) { 1077 if (is->is_ifp[i] != NULL) 1078 continue; 1079 is->is_ifp[i] = ipf_resolvenic(softc, is->is_ifname[i], 1080 is->is_v); 1081 } 1082 1083 /* 1084 * If we could trust is_hv, then the modulus would not be needed, 1085 * but when running with IPFILTER_SYNC, this stops bad values. 1086 */ 1087 hv = is->is_hv % softs->ipf_state_size; 1088 /* TRACE is, hv */ 1089 is->is_hv = hv; 1090 1091 /* 1092 * We need to get both of these locks...the first because it is 1093 * possible that once the insert is complete another packet might 1094 * come along, match the entry and want to update it. 1095 */ 1096 MUTEX_INIT(&is->is_lock, "ipf state entry"); 1097 MUTEX_ENTER(&is->is_lock); 1098 MUTEX_ENTER(&softs->ipf_stinsert); 1099 1100 fr = is->is_rule; 1101 if (fr != NULL) { 1102 if ((fr->fr_srctrack.ht_max_nodes != 0) && 1103 (ipf_ht_node_add(softc, &fr->fr_srctrack, 1104 is->is_family, &is->is_src) == -1)) { 1105 SBUMPD(ipf_state_stats, iss_max_track); 1106 MUTEX_EXIT(&softs->ipf_stinsert); 1107 return -1; 1108 } 1109 1110 MUTEX_ENTER(&fr->fr_lock); 1111 fr->fr_ref++; 1112 MUTEX_EXIT(&fr->fr_lock); 1113 fr->fr_statecnt++; 1114 } 1115 1116 if (is->is_flags & (SI_WILDP|SI_WILDA)) { 1117 DT(iss_wild_plus_one); 1118 SINCL(ipf_state_stats.iss_wild); 1119 } 1120 1121 SBUMP(ipf_state_stats.iss_proto[is->is_p]); 1122 SBUMP(ipf_state_stats.iss_active_proto[is->is_p]); 1123 1124 /* 1125 * add into list table. 1126 */ 1127 if (softs->ipf_state_list != NULL) 1128 softs->ipf_state_list->is_pnext = &is->is_next; 1129 is->is_pnext = &softs->ipf_state_list; 1130 is->is_next = softs->ipf_state_list; 1131 softs->ipf_state_list = is; 1132 1133 if (softs->ipf_state_table[hv] != NULL) 1134 softs->ipf_state_table[hv]->is_phnext = &is->is_hnext; 1135 else 1136 softs->ipf_state_stats.iss_inuse++; 1137 is->is_phnext = softs->ipf_state_table + hv; 1138 is->is_hnext = softs->ipf_state_table[hv]; 1139 softs->ipf_state_table[hv] = is; 1140 softs->ipf_state_stats.iss_bucketlen[hv]++; 1141 softs->ipf_state_stats.iss_active++; 1142 MUTEX_EXIT(&softs->ipf_stinsert); 1143 1144 ipf_state_setqueue(softc, is, rev); 1145 1146 return 0; 1147} 1148 1149 1150/* ------------------------------------------------------------------------ */ 1151/* Function: ipf_state_matchipv4addrs */ 1152/* Returns: int - 2 addresses match (strong match), 1 reverse match, */ 1153/* 0 no match */ 1154/* Parameters: is1, is2 pointers to states we are checking */ 1155/* */ 1156/* Function matches IPv4 addresses it returns strong match for ICMP proto */ 1157/* even there is only reverse match */ 1158/* ------------------------------------------------------------------------ */ 1159static int 1160ipf_state_matchipv4addrs(is1, is2) 1161 ipstate_t *is1, *is2; 1162{ 1163 int rv; 1164 1165 if (is1->is_saddr == is2->is_saddr && is1->is_daddr == is2->is_daddr) 1166 rv = 2; 1167 else if (is1->is_saddr == is2->is_daddr && 1168 is1->is_daddr == is2->is_saddr) { 1169 /* force strong match for ICMP protocol */ 1170 rv = (is1->is_p == IPPROTO_ICMP) ? 2 : 1; 1171 } 1172 else 1173 rv = 0; 1174 1175 return (rv); 1176} 1177 1178 1179/* ------------------------------------------------------------------------ */ 1180/* Function: ipf_state_matchipv6addrs */ 1181/* Returns: int - 2 addresses match (strong match), 1 reverse match, */ 1182/* 0 no match */ 1183/* Parameters: is1, is2 pointers to states we are checking */ 1184/* */ 1185/* Function matches IPv6 addresses it returns strong match for ICMP proto */ 1186/* even there is only reverse match */ 1187/* ------------------------------------------------------------------------ */ 1188static int 1189ipf_state_matchipv6addrs(is1, is2) 1190 ipstate_t *is1, *is2; 1191{ 1192 int rv; 1193 1194 if (IP6_EQ(&is1->is_src, &is2->is_src) && 1195 IP6_EQ(&is1->is_dst, &is2->is_dst)) 1196 rv = 2; 1197 else if (IP6_EQ(&is1->is_src, &is2->is_dst) && 1198 IP6_EQ(&is1->is_dst, &is2->is_src)) { 1199 /* force strong match for ICMPv6 protocol */ 1200 rv = (is1->is_p == IPPROTO_ICMPV6) ? 2 : 1; 1201 } 1202 else 1203 rv = 0; 1204 1205 return (rv); 1206} 1207 1208 1209/* ------------------------------------------------------------------------ */ 1210/* Function: ipf_state_matchaddresses */ 1211/* Returns: int - 2 addresses match, 1 reverse match, zero no match */ 1212/* Parameters: is1, is2 pointers to states we are checking */ 1213/* */ 1214/* function retruns true if two pairs of addresses belong to single */ 1215/* connection. suppose there are two endpoints: */ 1216/* endpoint1 1.1.1.1 */ 1217/* endpoint2 1.1.1.2 */ 1218/* */ 1219/* the state is established by packet flying from .1 to .2 so we see: */ 1220/* is1->src = 1.1.1.1 */ 1221/* is1->dst = 1.1.1.2 */ 1222/* now endpoint 1.1.1.2 sends answer */ 1223/* retreives is1 record created by first packat and compares it with is2 */ 1224/* temporal record, is2 is initialized as follows: */ 1225/* is2->src = 1.1.1.2 */ 1226/* is2->dst = 1.1.1.1 */ 1227/* in this case 1 will be returned */ 1228/* */ 1229/* the ipf_matchaddresses() assumes those two records to be same. of course */ 1230/* the ipf_matchaddresses() also assume records are same in case you pass */ 1231/* identical arguments (i.e. ipf_matchaddress(is1, is1) would return 2 */ 1232/* ------------------------------------------------------------------------ */ 1233static int 1234ipf_state_matchaddresses(is1, is2) 1235 ipstate_t *is1, *is2; 1236{ 1237 int rv; 1238 1239 if (is1->is_v == 4) { 1240 rv = ipf_state_matchipv4addrs(is1, is2); 1241 } 1242 else { 1243 rv = ipf_state_matchipv6addrs(is1, is2); 1244 } 1245 1246 return (rv); 1247} 1248 1249 1250/* ------------------------------------------------------------------------ */ 1251/* Function: ipf_matchports */ 1252/* Returns: int - 2 match, 1 rverse match, 0 no match */ 1253/* Parameters: ppairs1, ppairs - src, dst ports we want to match */ 1254/* */ 1255/* performs the same match for isps members as for addresses */ 1256/* ------------------------------------------------------------------------ */ 1257static int 1258ipf_state_matchports(ppairs1, ppairs2) 1259 udpinfo_t *ppairs1, *ppairs2; 1260{ 1261 int rv; 1262 1263 if (ppairs1->us_sport == ppairs2->us_sport && 1264 ppairs1->us_dport == ppairs2->us_dport) 1265 rv = 2; 1266 else if (ppairs1->us_sport == ppairs2->us_dport && 1267 ppairs1->us_dport == ppairs2->us_sport) 1268 rv = 1; 1269 else 1270 rv = 0; 1271 1272 return (rv); 1273} 1274 1275 1276/* ------------------------------------------------------------------------ */ 1277/* Function: ipf_matchisps */ 1278/* Returns: int - nonzero if isps members match, 0 nomatch */ 1279/* Parameters: is1, is2 - states we want to match */ 1280/* */ 1281/* performs the same match for isps members as for addresses */ 1282/* ------------------------------------------------------------------------ */ 1283static int 1284ipf_state_matchisps(is1, is2) 1285 ipstate_t *is1, *is2; 1286{ 1287 int rv; 1288 1289 if (is1->is_p == is2->is_p) { 1290 switch (is1->is_p) 1291 { 1292 case IPPROTO_TCP : 1293 case IPPROTO_UDP : 1294 case IPPROTO_GRE : 1295 /* greinfo_t can be also interprted as port pair */ 1296 rv = ipf_state_matchports(&is1->is_ps.is_us, 1297 &is2->is_ps.is_us); 1298 break; 1299 1300 case IPPROTO_ICMP : 1301 case IPPROTO_ICMPV6 : 1302 /* force strong match for ICMP datagram. */ 1303 if (bcmp(&is1->is_ps, &is2->is_ps, 1304 sizeof(icmpinfo_t)) == 0) { 1305 rv = 2; 1306 } else { 1307 rv = 0; 1308 } 1309 break; 1310 1311 default: 1312 rv = 0; 1313 } 1314 } else { 1315 rv = 0; 1316 } 1317 1318 return (rv); 1319} 1320 1321 1322/* ------------------------------------------------------------------------ */ 1323/* Function: ipf_state_match */ 1324/* Returns: int - nonzero match, zero no match */ 1325/* Parameters: is1, is2 - states we want to match */ 1326/* */ 1327/* ------------------------------------------------------------------------ */ 1328static int 1329ipf_state_match(is1, is2) 1330 ipstate_t *is1, *is2; 1331{ 1332 int rv; 1333 int amatch; 1334 int pomatch; 1335 1336 if (bcmp(&is1->is_pass, &is2->is_pass, 1337 offsetof(struct ipstate, is_authmsk) - 1338 offsetof(struct ipstate, is_pass)) == 0) { 1339 1340 pomatch = ipf_state_matchisps(is1, is2); 1341 amatch = ipf_state_matchaddresses(is1, is2); 1342 rv = (amatch != 0) && (amatch == pomatch); 1343 } else { 1344 rv = 0; 1345 } 1346 1347 return (rv); 1348} 1349 1350/* ------------------------------------------------------------------------ */ 1351/* Function: ipf_state_add */ 1352/* Returns: ipstate_t - 0 = success */ 1353/* Parameters: softc(I) - pointer to soft context main structure */ 1354/* fin(I) - pointer to packet information */ 1355/* stsave(O) - pointer to place to save pointer to created */ 1356/* state structure. */ 1357/* flags(I) - flags to use when creating the structure */ 1358/* */ 1359/* Creates a new IP state structure from the packet information collected. */ 1360/* Inserts it into the state table and appends to the bottom of the active */ 1361/* list. If the capacity of the table has reached the maximum allowed then */ 1362/* the call will fail and a flush is scheduled for the next timeout call. */ 1363/* */ 1364/* NOTE: The use of stsave to point to nat_state will result in memory */ 1365/* corruption. It should only be used to point to objects that will */ 1366/* either outlive this (not expired) or will deref the ip_state_t */ 1367/* when they are deleted. */ 1368/* ------------------------------------------------------------------------ */ 1369int 1370ipf_state_add(softc, fin, stsave, flags) 1371 ipf_main_softc_t *softc; 1372 fr_info_t *fin; 1373 ipstate_t **stsave; 1374 u_int flags; 1375{ 1376 ipf_state_softc_t *softs = softc->ipf_state_soft; 1377 ipstate_t *is, ips; 1378 struct icmp *ic; 1379 u_int pass, hv; 1380 frentry_t *fr; 1381 tcphdr_t *tcp; 1382 frdest_t *fdp; 1383 int out; 1384 1385 /* 1386 * If a packet that was created locally is trying to go out but we 1387 * do not match here here because of this lock, it is likely that 1388 * the policy will block it and return network unreachable back up 1389 * the stack. To mitigate this error, EAGAIN is returned instead, 1390 * telling the IP stack to try sending this packet again later. 1391 */ 1392 if (softs->ipf_state_lock) { 1393 SBUMPD(ipf_state_stats, iss_add_locked); 1394 fin->fin_error = EAGAIN; 1395 return -1; 1396 } 1397 1398 if (fin->fin_flx & (FI_SHORT|FI_STATE|FI_FRAGBODY|FI_BAD)) { 1399 SBUMPD(ipf_state_stats, iss_add_bad); 1400 return -1; 1401 } 1402 1403 if ((fin->fin_flx & FI_OOW) && !(fin->fin_tcpf & TH_SYN)) { 1404 SBUMPD(ipf_state_stats, iss_add_oow); 1405 return -1; 1406 } 1407 1408 if ((softs->ipf_state_stats.iss_active * 100 / softs->ipf_state_max) > 1409 softs->ipf_state_wm_high) { 1410 softs->ipf_state_doflush = 1; 1411 } 1412 1413 /* 1414 * If a "keep state" rule has reached the maximum number of references 1415 * to it, then schedule an automatic flush in case we can clear out 1416 * some "dead old wood". Note that because the lock isn't held on 1417 * fr it is possible that we could overflow. The cost of overflowing 1418 * is being ignored here as the number by which it can overflow is 1419 * a product of the number of simultaneous threads that could be 1420 * executing in here, so a limit of 100 won't result in 200, but could 1421 * result in 101 or 102. 1422 */ 1423 fr = fin->fin_fr; 1424 if (fr != NULL) { 1425 if ((softs->ipf_state_stats.iss_active >= 1426 softs->ipf_state_max) && (fr->fr_statemax == 0)) { 1427 SBUMPD(ipf_state_stats, iss_max); 1428 return 1; 1429 } 1430 if ((fr->fr_statemax != 0) && 1431 (fr->fr_statecnt >= fr->fr_statemax)) { 1432 SBUMPD(ipf_state_stats, iss_max_ref); 1433 return 2; 1434 } 1435 } 1436 1437 is = &ips; 1438 if (fr == NULL) { 1439 pass = softc->ipf_flags; 1440 is->is_tag = FR_NOLOGTAG; 1441 } else { 1442 pass = fr->fr_flags; 1443 } 1444 1445 ic = NULL; 1446 tcp = NULL; 1447 out = fin->fin_out; 1448 bzero((char *)is, sizeof(*is)); 1449 is->is_die = 1 + softc->ipf_ticks; 1450 /* 1451 * We want to check everything that is a property of this packet, 1452 * but we don't (automatically) care about it's fragment status as 1453 * this may change. 1454 */ 1455 is->is_pass = pass; 1456 is->is_v = fin->fin_v; 1457 is->is_sec = fin->fin_secmsk; 1458 is->is_secmsk = 0xffff; 1459 is->is_auth = fin->fin_auth; 1460 is->is_authmsk = 0xffff; 1461 is->is_family = fin->fin_family; 1462 is->is_opt[0] = fin->fin_optmsk; 1463 is->is_optmsk[0] = 0xffffffff; 1464 if (is->is_v == 6) { 1465 is->is_opt[0] &= ~0x8; 1466 is->is_optmsk[0] &= ~0x8; 1467 } 1468 1469 /* 1470 * Copy and calculate... 1471 */ 1472 hv = (is->is_p = fin->fin_fi.fi_p); 1473 is->is_src = fin->fin_fi.fi_src; 1474 hv += is->is_saddr; 1475 is->is_dst = fin->fin_fi.fi_dst; 1476 hv += is->is_daddr; 1477#ifdef USE_INET6 1478 if (fin->fin_v == 6) { 1479 /* 1480 * For ICMPv6, we check to see if the destination address is 1481 * a multicast address. If it is, do not include it in the 1482 * calculation of the hash because the correct reply will come 1483 * back from a real address, not a multicast address. 1484 */ 1485 if ((is->is_p == IPPROTO_ICMPV6) && 1486 IN6_IS_ADDR_MULTICAST(&is->is_dst.in6)) { 1487 /* 1488 * So you can do keep state with neighbour discovery. 1489 * 1490 * Here we could use the address from the neighbour 1491 * solicit message to put in the state structure and 1492 * we could use that without a wildcard flag too... 1493 */ 1494 flags |= SI_W_DADDR; 1495 hv -= is->is_daddr; 1496 } else { 1497 hv += is->is_dst.i6[1]; 1498 hv += is->is_dst.i6[2]; 1499 hv += is->is_dst.i6[3]; 1500 } 1501 hv += is->is_src.i6[1]; 1502 hv += is->is_src.i6[2]; 1503 hv += is->is_src.i6[3]; 1504 } 1505#endif 1506 if ((fin->fin_v == 4) && 1507 (fin->fin_flx & (FI_MULTICAST|FI_BROADCAST|FI_MBCAST))) { 1508 flags |= SI_W_DADDR; 1509 hv -= is->is_daddr; 1510 } 1511 1512 switch (is->is_p) 1513 { 1514#ifdef USE_INET6 1515 case IPPROTO_ICMPV6 : 1516 ic = fin->fin_dp; 1517 1518 switch (ic->icmp_type) 1519 { 1520 case ICMP6_ECHO_REQUEST : 1521 hv += (is->is_icmp.ici_id = ic->icmp_id); 1522 /*FALLTHROUGH*/ 1523 case ICMP6_MEMBERSHIP_QUERY : 1524 case ND_ROUTER_SOLICIT : 1525 case ND_NEIGHBOR_SOLICIT : 1526 case ICMP6_NI_QUERY : 1527 is->is_icmp.ici_type = ic->icmp_type; 1528 break; 1529 default : 1530 SBUMPD(ipf_state_stats, iss_icmp6_notquery); 1531 return -2; 1532 } 1533 break; 1534#endif 1535 case IPPROTO_ICMP : 1536 ic = fin->fin_dp; 1537 1538 switch (ic->icmp_type) 1539 { 1540 case ICMP_ECHO : 1541 case ICMP_TSTAMP : 1542 case ICMP_IREQ : 1543 case ICMP_MASKREQ : 1544 is->is_icmp.ici_type = ic->icmp_type; 1545 hv += (is->is_icmp.ici_id = ic->icmp_id); 1546 break; 1547 default : 1548 SBUMPD(ipf_state_stats, iss_icmp_notquery); 1549 return -3; 1550 } 1551 break; 1552 1553#if 0 1554 case IPPROTO_GRE : 1555 gre = fin->fin_dp; 1556 1557 is->is_gre.gs_flags = gre->gr_flags; 1558 is->is_gre.gs_ptype = gre->gr_ptype; 1559 if (GRE_REV(is->is_gre.gs_flags) == 1) { 1560 is->is_call[0] = fin->fin_data[0]; 1561 is->is_call[1] = fin->fin_data[1]; 1562 } 1563 break; 1564#endif 1565 1566 case IPPROTO_TCP : 1567 tcp = fin->fin_dp; 1568 1569 if (tcp->th_flags & TH_RST) { 1570 SBUMPD(ipf_state_stats, iss_tcp_rstadd); 1571 return -4; 1572 } 1573 1574 /* TRACE is, flags, hv */ 1575 1576 /* 1577 * The endian of the ports doesn't matter, but the ack and 1578 * sequence numbers do as we do mathematics on them later. 1579 */ 1580 is->is_sport = htons(fin->fin_data[0]); 1581 is->is_dport = htons(fin->fin_data[1]); 1582 if ((flags & (SI_W_DPORT|SI_W_SPORT)) == 0) { 1583 hv += is->is_sport; 1584 hv += is->is_dport; 1585 } 1586 1587 /* TRACE is, flags, hv */ 1588 1589 /* 1590 * If this is a real packet then initialise fields in the 1591 * state information structure from the TCP header information. 1592 */ 1593 1594 is->is_maxdwin = 1; 1595 is->is_maxswin = ntohs(tcp->th_win); 1596 if (is->is_maxswin == 0) 1597 is->is_maxswin = 1; 1598 1599 if ((fin->fin_flx & FI_IGNORE) == 0) { 1600 is->is_send = ntohl(tcp->th_seq) + fin->fin_dlen - 1601 (TCP_OFF(tcp) << 2) + 1602 ((tcp->th_flags & TH_SYN) ? 1 : 0) + 1603 ((tcp->th_flags & TH_FIN) ? 1 : 0); 1604 is->is_maxsend = is->is_send; 1605 1606 /* 1607 * Window scale option is only present in 1608 * SYN/SYN-ACK packet. 1609 */ 1610 if ((tcp->th_flags & ~(TH_FIN|TH_ACK|TH_ECNALL)) == 1611 TH_SYN && 1612 (TCP_OFF(tcp) > (sizeof(tcphdr_t) >> 2))) { 1613 if (ipf_tcpoptions(softs, fin, tcp, 1614 &is->is_tcp.ts_data[0]) == -1) 1615 fin->fin_flx |= FI_BAD; 1616 } 1617 1618 if ((fin->fin_out != 0) && (pass & FR_NEWISN) != 0) { 1619 ipf_checknewisn(fin, is); 1620 ipf_fixoutisn(fin, is); 1621 } 1622 1623 if ((tcp->th_flags & TH_OPENING) == TH_SYN) 1624 flags |= IS_TCPFSM; 1625 else { 1626 is->is_maxdwin = is->is_maxswin * 2; 1627 is->is_dend = ntohl(tcp->th_ack); 1628 is->is_maxdend = ntohl(tcp->th_ack); 1629 is->is_maxdwin *= 2; 1630 } 1631 } 1632 1633 /* 1634 * If we're creating state for a starting connection, start 1635 * the timer on it as we'll never see an error if it fails 1636 * to connect. 1637 */ 1638 break; 1639 1640 case IPPROTO_UDP : 1641 tcp = fin->fin_dp; 1642 1643 is->is_sport = htons(fin->fin_data[0]); 1644 is->is_dport = htons(fin->fin_data[1]); 1645 if ((flags & (SI_W_DPORT|SI_W_SPORT)) == 0) { 1646 hv += tcp->th_dport; 1647 hv += tcp->th_sport; 1648 } 1649 break; 1650 1651 default : 1652 break; 1653 } 1654 hv = DOUBLE_HASH(hv); 1655 is->is_hv = hv; 1656 1657 /* 1658 * Look for identical state. 1659 */ 1660 for (is = softs->ipf_state_table[hv % softs->ipf_state_size]; 1661 is != NULL; is = is->is_hnext) { 1662 if (ipf_state_match(&ips, is) == 1) 1663 break; 1664 } 1665 if (is != NULL) { 1666 SBUMPD(ipf_state_stats, iss_add_dup); 1667 return 3; 1668 } 1669 1670 if (softs->ipf_state_stats.iss_bucketlen[hv] >= 1671 softs->ipf_state_maxbucket) { 1672 SBUMPD(ipf_state_stats, iss_bucket_full); 1673 return 4; 1674 } 1675 1676 /* 1677 * No existing state; create new 1678 */ 1679 KMALLOC(is, ipstate_t *); 1680 if (is == NULL) { 1681 SBUMPD(ipf_state_stats, iss_nomem); 1682 return 5; 1683 } 1684 bcopy((char *)&ips, (char *)is, sizeof(*is)); 1685 is->is_flags = flags & IS_INHERITED; 1686 is->is_rulen = fin->fin_rule; 1687 is->is_rule = fr; 1688 1689 /* 1690 * Do not do the modulus here, it is done in ipf_state_insert(). 1691 */ 1692 if (fr != NULL) { 1693 ipftq_t *tq; 1694 1695 (void) strncpy(is->is_group, FR_NAME(fr, fr_group), 1696 FR_GROUPLEN); 1697 if (fr->fr_age[0] != 0) { 1698 tq = ipf_addtimeoutqueue(softc, 1699 &softs->ipf_state_usertq, 1700 fr->fr_age[0]); 1701 is->is_tqehead[0] = tq; 1702 is->is_sti.tqe_flags |= TQE_RULEBASED; 1703 } 1704 if (fr->fr_age[1] != 0) { 1705 tq = ipf_addtimeoutqueue(softc, 1706 &softs->ipf_state_usertq, 1707 fr->fr_age[1]); 1708 is->is_tqehead[1] = tq; 1709 is->is_sti.tqe_flags |= TQE_RULEBASED; 1710 } 1711 1712 is->is_tag = fr->fr_logtag; 1713 } 1714 1715 /* 1716 * It may seem strange to set is_ref to 2, but if stsave is not NULL 1717 * then a copy of the pointer is being stored somewhere else and in 1718 * the end, it will expect to be able to do something with it. 1719 */ 1720 is->is_me = stsave; 1721 if (stsave != NULL) { 1722 *stsave = is; 1723 is->is_ref = 2; 1724 } else { 1725 is->is_ref = 1; 1726 } 1727 is->is_pkts[0] = 0, is->is_bytes[0] = 0; 1728 is->is_pkts[1] = 0, is->is_bytes[1] = 0; 1729 is->is_pkts[2] = 0, is->is_bytes[2] = 0; 1730 is->is_pkts[3] = 0, is->is_bytes[3] = 0; 1731 if ((fin->fin_flx & FI_IGNORE) == 0) { 1732 is->is_pkts[out] = 1; 1733 fin->fin_pktnum = 1; 1734 is->is_bytes[out] = fin->fin_plen; 1735 is->is_flx[out][0] = fin->fin_flx & FI_CMP; 1736 is->is_flx[out][0] &= ~FI_OOW; 1737 } 1738 1739 if (pass & FR_STLOOSE) 1740 is->is_flags |= IS_LOOSE; 1741 1742 if (pass & FR_STSTRICT) 1743 is->is_flags |= IS_STRICT; 1744 1745 if (pass & FR_STATESYNC) 1746 is->is_flags |= IS_STATESYNC; 1747 1748 if (pass & FR_LOGFIRST) 1749 is->is_pass &= ~(FR_LOGFIRST|FR_LOG); 1750 1751 READ_ENTER(&softc->ipf_state); 1752 1753 if (ipf_state_insert(softc, is, fin->fin_rev) == -1) { 1754 RWLOCK_EXIT(&softc->ipf_state); 1755 /* 1756 * This is a bit more manual than it should be but 1757 * ipf_state_del cannot be called. 1758 */ 1759 MUTEX_EXIT(&is->is_lock); 1760 MUTEX_DESTROY(&is->is_lock); 1761 if (is->is_tqehead[0] != NULL) { 1762 if (ipf_deletetimeoutqueue(is->is_tqehead[0]) == 0) 1763 ipf_freetimeoutqueue(softc, is->is_tqehead[0]); 1764 is->is_tqehead[0] = NULL; 1765 } 1766 if (is->is_tqehead[1] != NULL) { 1767 if (ipf_deletetimeoutqueue(is->is_tqehead[1]) == 0) 1768 ipf_freetimeoutqueue(softc, is->is_tqehead[1]); 1769 is->is_tqehead[1] = NULL; 1770 } 1771 KFREE(is); 1772 return -1; 1773 } 1774 1775 /* 1776 * Filling in the interface name is after the insert so that an 1777 * event (such as add/delete) of an interface that is referenced 1778 * by this rule will see this state entry. 1779 */ 1780 if (fr != NULL) { 1781 /* 1782 * The name '-' is special for network interfaces and causes 1783 * a NULL name to be present, always, allowing packets to 1784 * match it, regardless of their interface. 1785 */ 1786 if ((fin->fin_ifp == NULL) || 1787 (fr->fr_ifnames[out << 1] != -1 && 1788 fr->fr_names[fr->fr_ifnames[out << 1] + 0] == '-' && 1789 fr->fr_names[fr->fr_ifnames[out << 1] + 1] == '\0')) { 1790 is->is_ifp[out << 1] = fr->fr_ifas[0]; 1791 strncpy(is->is_ifname[out << 1], 1792 fr->fr_names + fr->fr_ifnames[0], 1793 sizeof(fr->fr_ifnames[0])); 1794 } else { 1795 is->is_ifp[out << 1] = fin->fin_ifp; 1796 COPYIFNAME(fin->fin_v, fin->fin_ifp, 1797 is->is_ifname[out << 1]); 1798 } 1799 1800 is->is_ifp[(out << 1) + 1] = fr->fr_ifas[1]; 1801 if (fr->fr_ifnames[1] != -1) { 1802 strncpy(is->is_ifname[(out << 1) + 1], 1803 fr->fr_names + fr->fr_ifnames[1], 1804 sizeof(fr->fr_ifnames[1])); 1805 } 1806 1807 is->is_ifp[(1 - out) << 1] = fr->fr_ifas[2]; 1808 if (fr->fr_ifnames[2] != -1) { 1809 strncpy(is->is_ifname[((1 - out) << 1)], 1810 fr->fr_names + fr->fr_ifnames[2], 1811 sizeof(fr->fr_ifnames[2])); 1812 } 1813 1814 is->is_ifp[((1 - out) << 1) + 1] = fr->fr_ifas[3]; 1815 if (fr->fr_ifnames[3] != -1) { 1816 strncpy(is->is_ifname[((1 - out) << 1) + 1], 1817 fr->fr_names + fr->fr_ifnames[3], 1818 sizeof(fr->fr_ifnames[3])); 1819 } 1820 } else { 1821 if (fin->fin_ifp != NULL) { 1822 is->is_ifp[out << 1] = fin->fin_ifp; 1823 COPYIFNAME(fin->fin_v, fin->fin_ifp, 1824 is->is_ifname[out << 1]); 1825 } 1826 } 1827 1828 if (fin->fin_p == IPPROTO_TCP) { 1829 /* 1830 * If we're creating state for a starting connection, start the 1831 * timer on it as we'll never see an error if it fails to 1832 * connect. 1833 */ 1834 (void) ipf_tcp_age(&is->is_sti, fin, softs->ipf_state_tcptq, 1835 is->is_flags, 2); 1836 } 1837 MUTEX_EXIT(&is->is_lock); 1838 if ((is->is_flags & IS_STATESYNC) && ((is->is_flags & SI_CLONE) == 0)) 1839 is->is_sync = ipf_sync_new(softc, SMC_STATE, fin, is); 1840 if (softs->ipf_state_logging) 1841 ipf_state_log(softc, is, ISL_NEW); 1842 1843 RWLOCK_EXIT(&softc->ipf_state); 1844 1845 fin->fin_flx |= FI_STATE; 1846 if (fin->fin_flx & FI_FRAG) 1847 (void) ipf_frag_new(softc, fin, pass); 1848 1849 fdp = &fr->fr_tifs[0]; 1850 if (fdp->fd_type == FRD_DSTLIST) { 1851 ipf_dstlist_select_node(fin, fdp->fd_ptr, NULL, 1852 &is->is_tifs[0]); 1853 } else { 1854 bcopy(fdp, &is->is_tifs[0], sizeof(*fdp)); 1855 } 1856 1857 fdp = &fr->fr_tifs[1]; 1858 if (fdp->fd_type == FRD_DSTLIST) { 1859 ipf_dstlist_select_node(fin, fdp->fd_ptr, NULL, 1860 &is->is_tifs[1]); 1861 } else { 1862 bcopy(fdp, &is->is_tifs[1], sizeof(*fdp)); 1863 } 1864 fin->fin_tif = &is->is_tifs[fin->fin_rev]; 1865 1866 fdp = &fr->fr_dif; 1867 if (fdp->fd_type == FRD_DSTLIST) { 1868 ipf_dstlist_select_node(fin, fdp->fd_ptr, NULL, 1869 &is->is_dif); 1870 } else { 1871 bcopy(fdp, &is->is_dif, sizeof(*fdp)); 1872 } 1873 fin->fin_dif = &is->is_dif; 1874 1875 return 0; 1876} 1877 1878 1879/* ------------------------------------------------------------------------ */ 1880/* Function: ipf_tcpoptions */ 1881/* Returns: int - 1 == packet matches state entry, 0 == it does not, */ 1882/* -1 == packet has bad TCP options data */ 1883/* Parameters: softs(I) - pointer to state context structure */ 1884/* fin(I) - pointer to packet information */ 1885/* tcp(I) - pointer to TCP packet header */ 1886/* td(I) - pointer to TCP data held as part of the state */ 1887/* */ 1888/* Look after the TCP header for any options and deal with those that are */ 1889/* present. Record details about those that we recogise. */ 1890/* ------------------------------------------------------------------------ */ 1891static int 1892ipf_tcpoptions(softs, fin, tcp, td) 1893 ipf_state_softc_t *softs; 1894 fr_info_t *fin; 1895 tcphdr_t *tcp; 1896 tcpdata_t *td; 1897{ 1898 int off, mlen, ol, i, len, retval; 1899 char buf[64], *s, opt; 1900 mb_t *m = NULL; 1901 1902 len = (TCP_OFF(tcp) << 2); 1903 if (fin->fin_dlen < len) { 1904 SBUMPD(ipf_state_stats, iss_tcp_toosmall); 1905 return 0; 1906 } 1907 len -= sizeof(*tcp); 1908 1909 off = fin->fin_plen - fin->fin_dlen + sizeof(*tcp) + fin->fin_ipoff; 1910 1911 m = fin->fin_m; 1912 mlen = MSGDSIZE(m) - off; 1913 if (len > mlen) { 1914 len = mlen; 1915 retval = 0; 1916 } else { 1917 retval = 1; 1918 } 1919 1920 COPYDATA(m, off, len, buf); 1921 1922 for (s = buf; len > 0; ) { 1923 opt = *s; 1924 if (opt == TCPOPT_EOL) 1925 break; 1926 else if (opt == TCPOPT_NOP) 1927 ol = 1; 1928 else { 1929 if (len < 2) 1930 break; 1931 ol = (int)*(s + 1); 1932 if (ol < 2 || ol > len) 1933 break; 1934 1935 /* 1936 * Extract the TCP options we are interested in out of 1937 * the header and store them in the the tcpdata struct. 1938 */ 1939 switch (opt) 1940 { 1941 case TCPOPT_WINDOW : 1942 if (ol == TCPOLEN_WINDOW) { 1943 i = (int)*(s + 2); 1944 if (i > TCP_WSCALE_MAX) 1945 i = TCP_WSCALE_MAX; 1946 else if (i < 0) 1947 i = 0; 1948 td->td_winscale = i; 1949 td->td_winflags |= TCP_WSCALE_SEEN| 1950 TCP_WSCALE_FIRST; 1951 } else 1952 retval = -1; 1953 break; 1954 case TCPOPT_MAXSEG : 1955 /* 1956 * So, if we wanted to set the TCP MAXSEG, 1957 * it should be done here... 1958 */ 1959 if (ol == TCPOLEN_MAXSEG) { 1960 i = (int)*(s + 2); 1961 i <<= 8; 1962 i += (int)*(s + 3); 1963 td->td_maxseg = i; 1964 } else 1965 retval = -1; 1966 break; 1967 case TCPOPT_SACK_PERMITTED : 1968 if (ol == TCPOLEN_SACK_PERMITTED) 1969 td->td_winflags |= TCP_SACK_PERMIT; 1970 else 1971 retval = -1; 1972 break; 1973 } 1974 } 1975 len -= ol; 1976 s += ol; 1977 } 1978 if (retval == -1) { 1979 SBUMPD(ipf_state_stats, iss_tcp_badopt); 1980 } 1981 return retval; 1982} 1983 1984 1985/* ------------------------------------------------------------------------ */ 1986/* Function: ipf_state_tcp */ 1987/* Returns: int - 1 == packet matches state entry, 0 == it does not */ 1988/* Parameters: softc(I) - pointer to soft context main structure */ 1989/* softs(I) - pointer to state context structure */ 1990/* fin(I) - pointer to packet information */ 1991/* tcp(I) - pointer to TCP packet header */ 1992/* is(I) - pointer to master state structure */ 1993/* */ 1994/* Check to see if a packet with TCP headers fits within the TCP window. */ 1995/* Change timeout depending on whether new packet is a SYN-ACK returning */ 1996/* for a SYN or a RST or FIN which indicate time to close up shop. */ 1997/* ------------------------------------------------------------------------ */ 1998static int 1999ipf_state_tcp(softc, softs, fin, tcp, is) 2000 ipf_main_softc_t *softc; 2001 ipf_state_softc_t *softs; 2002 fr_info_t *fin; 2003 tcphdr_t *tcp; 2004 ipstate_t *is; 2005{ 2006 tcpdata_t *fdata, *tdata; 2007 int source, ret, flags; 2008 2009 source = !fin->fin_rev; 2010 if (((is->is_flags & IS_TCPFSM) != 0) && (source == 1) && 2011 (ntohs(is->is_sport) != fin->fin_data[0])) 2012 source = 0; 2013 fdata = &is->is_tcp.ts_data[!source]; 2014 tdata = &is->is_tcp.ts_data[source]; 2015 2016 MUTEX_ENTER(&is->is_lock); 2017 2018 /* 2019 * If a SYN packet is received for a connection that is on the way out 2020 * but hasn't yet departed then advance this session along the way. 2021 */ 2022 if ((tcp->th_flags & TH_OPENING) == TH_SYN) { 2023 if ((is->is_state[0] > IPF_TCPS_ESTABLISHED) && 2024 (is->is_state[1] > IPF_TCPS_ESTABLISHED)) { 2025 is->is_state[!source] = IPF_TCPS_CLOSED; 2026 ipf_movequeue(softc->ipf_ticks, &is->is_sti, 2027 is->is_sti.tqe_ifq, 2028 &softs->ipf_state_deletetq); 2029 MUTEX_EXIT(&is->is_lock); 2030 DT1(iss_tcp_closing, ipstate_t *, is); 2031 SBUMP(ipf_state_stats.iss_tcp_closing); 2032 return 0; 2033 } 2034 } 2035 2036 if (is->is_flags & IS_LOOSE) 2037 ret = 1; 2038 else 2039 ret = ipf_state_tcpinwindow(fin, fdata, tdata, tcp, 2040 is->is_flags); 2041 if (ret > 0) { 2042 /* 2043 * Nearing end of connection, start timeout. 2044 */ 2045 ret = ipf_tcp_age(&is->is_sti, fin, softs->ipf_state_tcptq, 2046 is->is_flags, ret); 2047 if (ret == 0) { 2048 MUTEX_EXIT(&is->is_lock); 2049 DT2(iss_tcp_fsm, fr_info_t *, fin, ipstate_t *, is); 2050 SBUMP(ipf_state_stats.iss_tcp_fsm); 2051 return 0; 2052 } 2053 2054 if (softs->ipf_state_logging > 4) 2055 ipf_state_log(softc, is, ISL_STATECHANGE); 2056 2057 /* 2058 * set s0's as appropriate. Use syn-ack packet as it 2059 * contains both pieces of required information. 2060 */ 2061 /* 2062 * Window scale option is only present in SYN/SYN-ACK packet. 2063 * Compare with ~TH_FIN to mask out T/TCP setups. 2064 */ 2065 flags = tcp->th_flags & ~(TH_FIN|TH_ECNALL); 2066 if (flags == (TH_SYN|TH_ACK)) { 2067 is->is_s0[source] = ntohl(tcp->th_ack); 2068 is->is_s0[!source] = ntohl(tcp->th_seq) + 1; 2069 if ((TCP_OFF(tcp) > (sizeof(tcphdr_t) >> 2))) { 2070 if (ipf_tcpoptions(softs, fin, tcp, 2071 fdata) == -1) 2072 fin->fin_flx |= FI_BAD; 2073 } 2074 if ((fin->fin_out != 0) && (is->is_pass & FR_NEWISN)) 2075 ipf_checknewisn(fin, is); 2076 } else if (flags == TH_SYN) { 2077 is->is_s0[source] = ntohl(tcp->th_seq) + 1; 2078 if ((TCP_OFF(tcp) > (sizeof(tcphdr_t) >> 2))) { 2079 if (ipf_tcpoptions(softs, fin, tcp, 2080 fdata) == -1) 2081 fin->fin_flx |= FI_BAD; 2082 } 2083 2084 if ((fin->fin_out != 0) && (is->is_pass & FR_NEWISN)) 2085 ipf_checknewisn(fin, is); 2086 2087 } 2088 ret = 1; 2089 } else { 2090 DT2(iss_tcp_oow, fr_info_t *, fin, ipstate_t *, is); 2091 SBUMP(ipf_state_stats.iss_tcp_oow); 2092 ret = 0; 2093 } 2094 MUTEX_EXIT(&is->is_lock); 2095 return ret; 2096} 2097 2098 2099/* ------------------------------------------------------------------------ */ 2100/* Function: ipf_checknewisn */ 2101/* Returns: Nil */ 2102/* Parameters: fin(I) - pointer to packet information */ 2103/* is(I) - pointer to master state structure */ 2104/* */ 2105/* Check to see if this TCP connection is expecting and needs a new */ 2106/* sequence number for a particular direction of the connection. */ 2107/* */ 2108/* NOTE: This does not actually change the sequence numbers, only gets new */ 2109/* one ready. */ 2110/* ------------------------------------------------------------------------ */ 2111static void 2112ipf_checknewisn(fin, is) 2113 fr_info_t *fin; 2114 ipstate_t *is; 2115{ 2116 u_32_t sumd, old, new; 2117 tcphdr_t *tcp; 2118 int i; 2119 2120 i = fin->fin_rev; 2121 tcp = fin->fin_dp; 2122 2123 if (((i == 0) && !(is->is_flags & IS_ISNSYN)) || 2124 ((i == 1) && !(is->is_flags & IS_ISNACK))) { 2125 old = ntohl(tcp->th_seq); 2126 new = ipf_newisn(fin); 2127 is->is_isninc[i] = new - old; 2128 CALC_SUMD(old, new, sumd); 2129 is->is_sumd[i] = (sumd & 0xffff) + (sumd >> 16); 2130 2131 is->is_flags |= ((i == 0) ? IS_ISNSYN : IS_ISNACK); 2132 } 2133} 2134 2135 2136/* ------------------------------------------------------------------------ */ 2137/* Function: ipf_state_tcpinwindow */ 2138/* Returns: int - 1 == packet inside TCP "window", 0 == not inside. */ 2139/* Parameters: fin(I) - pointer to packet information */ 2140/* fdata(I) - pointer to tcp state informatio (forward) */ 2141/* tdata(I) - pointer to tcp state informatio (reverse) */ 2142/* tcp(I) - pointer to TCP packet header */ 2143/* */ 2144/* Given a packet has matched addresses and ports, check to see if it is */ 2145/* within the TCP data window. In a show of generosity, allow packets that */ 2146/* are within the window space behind the current sequence # as well. */ 2147/* ------------------------------------------------------------------------ */ 2148static int 2149ipf_state_tcpinwindow(fin, fdata, tdata, tcp, flags) 2150 fr_info_t *fin; 2151 tcpdata_t *fdata, *tdata; 2152 tcphdr_t *tcp; 2153 int flags; 2154{ 2155 ipf_main_softc_t *softc = fin->fin_main_soft; 2156 ipf_state_softc_t *softs = softc->ipf_state_soft; 2157 tcp_seq seq, ack, end; 2158 int ackskew, tcpflags; 2159 u_32_t win, maxwin; 2160 int dsize, inseq; 2161 2162 /* 2163 * Find difference between last checked packet and this packet. 2164 */ 2165 tcpflags = tcp->th_flags; 2166 seq = ntohl(tcp->th_seq); 2167 ack = ntohl(tcp->th_ack); 2168 if (tcpflags & TH_SYN) 2169 win = ntohs(tcp->th_win); 2170 else 2171 win = ntohs(tcp->th_win) << fdata->td_winscale; 2172 2173 /* 2174 * A window of 0 produces undesirable behaviour from this function. 2175 */ 2176 if (win == 0) 2177 win = 1; 2178 2179 dsize = fin->fin_dlen - (TCP_OFF(tcp) << 2) + 2180 ((tcpflags & TH_SYN) ? 1 : 0) + ((tcpflags & TH_FIN) ? 1 : 0); 2181 2182 /* 2183 * if window scaling is present, the scaling is only allowed 2184 * for windows not in the first SYN packet. In that packet the 2185 * window is 65535 to specify the largest window possible 2186 * for receivers not implementing the window scale option. 2187 * Currently, we do not assume TTCP here. That means that 2188 * if we see a second packet from a host (after the initial 2189 * SYN), we can assume that the receiver of the SYN did 2190 * already send back the SYN/ACK (and thus that we know if 2191 * the receiver also does window scaling) 2192 */ 2193 if (!(tcpflags & TH_SYN) && (fdata->td_winflags & TCP_WSCALE_FIRST)) { 2194 fdata->td_winflags &= ~TCP_WSCALE_FIRST; 2195 fdata->td_maxwin = win; 2196 } 2197 2198 end = seq + dsize; 2199 2200 if ((fdata->td_end == 0) && 2201 (!(flags & IS_TCPFSM) || 2202 ((tcpflags & TH_OPENING) == TH_OPENING))) { 2203 /* 2204 * Must be a (outgoing) SYN-ACK in reply to a SYN. 2205 */ 2206 fdata->td_end = end - 1; 2207 fdata->td_maxwin = 1; 2208 fdata->td_maxend = end + win; 2209 } 2210 2211 if (!(tcpflags & TH_ACK)) { /* Pretend an ack was sent */ 2212 ack = tdata->td_end; 2213 } else if (((tcpflags & (TH_ACK|TH_RST)) == (TH_ACK|TH_RST)) && 2214 (ack == 0)) { 2215 /* gross hack to get around certain broken tcp stacks */ 2216 ack = tdata->td_end; 2217 } 2218 2219 maxwin = tdata->td_maxwin; 2220 ackskew = tdata->td_end - ack; 2221 2222 /* 2223 * Strict sequencing only allows in-order delivery. 2224 */ 2225 if ((flags & IS_STRICT) != 0) { 2226 if (seq != fdata->td_end) { 2227 DT2(iss_tcp_struct, tcpdata_t *, fdata, int, seq); 2228 SBUMP(ipf_state_stats.iss_tcp_strict); 2229 fin->fin_flx |= FI_OOW; 2230 return 0; 2231 } 2232 } 2233 2234#define SEQ_GE(a,b) ((int)((a) - (b)) >= 0) 2235#define SEQ_GT(a,b) ((int)((a) - (b)) > 0) 2236 inseq = 0; 2237 if ((SEQ_GE(fdata->td_maxend, end)) && 2238 (SEQ_GE(seq, fdata->td_end - maxwin)) && 2239/* XXX what about big packets */ 2240#define MAXACKWINDOW 66000 2241 (-ackskew <= (MAXACKWINDOW)) && 2242 ( ackskew <= (MAXACKWINDOW << fdata->td_winscale))) { 2243 inseq = 1; 2244 /* 2245 * Microsoft Windows will send the next packet to the right of the 2246 * window if SACK is in use. 2247 */ 2248 } else if ((seq == fdata->td_maxend) && (ackskew == 0) && 2249 (fdata->td_winflags & TCP_SACK_PERMIT) && 2250 (tdata->td_winflags & TCP_SACK_PERMIT)) { 2251 DT2(iss_sinsack, tcpdata_t *, fdata, int, seq); 2252 SBUMP(ipf_state_stats.iss_winsack); 2253 inseq = 1; 2254 /* 2255 * Sometimes a TCP RST will be generated with only the ACK field 2256 * set to non-zero. 2257 */ 2258 } else if ((seq == 0) && (tcpflags == (TH_RST|TH_ACK)) && 2259 (ackskew >= -1) && (ackskew <= 1)) { 2260 inseq = 1; 2261 } else if (!(flags & IS_TCPFSM)) { 2262 int i; 2263 2264 i = (fin->fin_rev << 1) + fin->fin_out; 2265 2266#if 0 2267 if (is_pkts[i]0 == 0) { 2268 /* 2269 * Picking up a connection in the middle, the "next" 2270 * packet seen from a direction that is new should be 2271 * accepted, even if it appears out of sequence. 2272 */ 2273 inseq = 1; 2274 } else 2275#endif 2276 if (!(fdata->td_winflags & 2277 (TCP_WSCALE_SEEN|TCP_WSCALE_FIRST))) { 2278 /* 2279 * No TCPFSM and no window scaling, so make some 2280 * extra guesses. 2281 */ 2282 if ((seq == fdata->td_maxend) && (ackskew == 0)) 2283 inseq = 1; 2284 else if (SEQ_GE(seq + maxwin, fdata->td_end - maxwin)) 2285 inseq = 1; 2286 } 2287 } 2288 2289 /* TRACE(inseq, fdata, tdata, seq, end, ack, ackskew, win, maxwin) */ 2290 2291 if (inseq) { 2292 /* if ackskew < 0 then this should be due to fragmented 2293 * packets. There is no way to know the length of the 2294 * total packet in advance. 2295 * We do know the total length from the fragment cache though. 2296 * Note however that there might be more sessions with 2297 * exactly the same source and destination parameters in the 2298 * state cache (and source and destination is the only stuff 2299 * that is saved in the fragment cache). Note further that 2300 * some TCP connections in the state cache are hashed with 2301 * sport and dport as well which makes it not worthwhile to 2302 * look for them. 2303 * Thus, when ackskew is negative but still seems to belong 2304 * to this session, we bump up the destinations end value. 2305 */ 2306 if (ackskew < 0) 2307 tdata->td_end = ack; 2308 2309 /* update max window seen */ 2310 if (fdata->td_maxwin < win) 2311 fdata->td_maxwin = win; 2312 if (SEQ_GT(end, fdata->td_end)) 2313 fdata->td_end = end; 2314 if (SEQ_GE(ack + win, tdata->td_maxend)) 2315 tdata->td_maxend = ack + win; 2316 return 1; 2317 } 2318 SBUMP(ipf_state_stats.iss_oow); 2319 fin->fin_flx |= FI_OOW; 2320 return 0; 2321} 2322 2323 2324/* ------------------------------------------------------------------------ */ 2325/* Function: ipf_state_clone */ 2326/* Returns: ipstate_t* - NULL == cloning failed, */ 2327/* else pointer to new state structure */ 2328/* Parameters: fin(I) - pointer to packet information */ 2329/* tcp(I) - pointer to TCP/UDP header */ 2330/* is(I) - pointer to master state structure */ 2331/* */ 2332/* Create a "duplcate" state table entry from the master. */ 2333/* ------------------------------------------------------------------------ */ 2334static ipstate_t * 2335ipf_state_clone(fin, tcp, is) 2336 fr_info_t *fin; 2337 tcphdr_t *tcp; 2338 ipstate_t *is; 2339{ 2340 ipf_main_softc_t *softc = fin->fin_main_soft; 2341 ipf_state_softc_t *softs = softc->ipf_state_soft; 2342 ipstate_t *clone; 2343 u_32_t send; 2344 2345 if (softs->ipf_state_stats.iss_active == softs->ipf_state_max) { 2346 SBUMPD(ipf_state_stats, iss_max); 2347 softs->ipf_state_doflush = 1; 2348 return NULL; 2349 } 2350 KMALLOC(clone, ipstate_t *); 2351 if (clone == NULL) { 2352 SBUMPD(ipf_state_stats, iss_clone_nomem); 2353 return NULL; 2354 } 2355 bcopy((char *)is, (char *)clone, sizeof(*clone)); 2356 2357 MUTEX_NUKE(&clone->is_lock); 2358 /* 2359 * It has not yet been placed on any timeout queue, so make sure 2360 * all of that data is zero'd out. 2361 */ 2362 clone->is_sti.tqe_pnext = NULL; 2363 clone->is_sti.tqe_next = NULL; 2364 clone->is_sti.tqe_ifq = NULL; 2365 clone->is_sti.tqe_parent = clone; 2366 2367 clone->is_die = ONE_DAY + softc->ipf_ticks; 2368 clone->is_state[0] = 0; 2369 clone->is_state[1] = 0; 2370 send = ntohl(tcp->th_seq) + fin->fin_dlen - (TCP_OFF(tcp) << 2) + 2371 ((tcp->th_flags & TH_SYN) ? 1 : 0) + 2372 ((tcp->th_flags & TH_FIN) ? 1 : 0); 2373 2374 if (fin->fin_rev == 1) { 2375 clone->is_dend = send; 2376 clone->is_maxdend = send; 2377 clone->is_send = 0; 2378 clone->is_maxswin = 1; 2379 clone->is_maxdwin = ntohs(tcp->th_win); 2380 if (clone->is_maxdwin == 0) 2381 clone->is_maxdwin = 1; 2382 } else { 2383 clone->is_send = send; 2384 clone->is_maxsend = send; 2385 clone->is_dend = 0; 2386 clone->is_maxdwin = 1; 2387 clone->is_maxswin = ntohs(tcp->th_win); 2388 if (clone->is_maxswin == 0) 2389 clone->is_maxswin = 1; 2390 } 2391 2392 clone->is_flags &= ~SI_CLONE; 2393 clone->is_flags |= SI_CLONED; 2394 if (ipf_state_insert(softc, clone, fin->fin_rev) == -1) { 2395 KFREE(clone); 2396 return NULL; 2397 } 2398 2399 clone->is_ref = 1; 2400 if (clone->is_p == IPPROTO_TCP) { 2401 (void) ipf_tcp_age(&clone->is_sti, fin, softs->ipf_state_tcptq, 2402 clone->is_flags, 2); 2403 } 2404 MUTEX_EXIT(&clone->is_lock); 2405 if (is->is_flags & IS_STATESYNC) 2406 clone->is_sync = ipf_sync_new(softc, SMC_STATE, fin, clone); 2407 DT2(iss_clone, ipstate_t *, is, ipstate_t *, clone); 2408 SBUMP(ipf_state_stats.iss_cloned); 2409 return clone; 2410} 2411 2412 2413/* ------------------------------------------------------------------------ */ 2414/* Function: ipf_matchsrcdst */ 2415/* Returns: Nil */ 2416/* Parameters: fin(I) - pointer to packet information */ 2417/* is(I) - pointer to state structure */ 2418/* src(I) - pointer to source address */ 2419/* dst(I) - pointer to destination address */ 2420/* tcp(I) - pointer to TCP/UDP header */ 2421/* cmask(I) - mask of FI_* bits to check */ 2422/* */ 2423/* Match a state table entry against an IP packet. The logic below is that */ 2424/* ret gets set to one if the match succeeds, else remains 0. If it is */ 2425/* still 0 after the test. no match. */ 2426/* ------------------------------------------------------------------------ */ 2427static ipstate_t * 2428ipf_matchsrcdst(fin, is, src, dst, tcp, cmask) 2429 fr_info_t *fin; 2430 ipstate_t *is; 2431 i6addr_t *src, *dst; 2432 tcphdr_t *tcp; 2433 u_32_t cmask; 2434{ 2435 ipf_main_softc_t *softc = fin->fin_main_soft; 2436 ipf_state_softc_t *softs = softc->ipf_state_soft; 2437 int ret = 0, rev, out, flags, flx = 0, idx; 2438 u_short sp, dp; 2439 u_32_t cflx; 2440 void *ifp; 2441 2442 /* 2443 * If a connection is about to be deleted, no packets 2444 * are allowed to match it. 2445 */ 2446 if (is->is_sti.tqe_ifq == &softs->ipf_state_deletetq) 2447 return NULL; 2448 2449 rev = IP6_NEQ(&is->is_dst, dst); 2450 ifp = fin->fin_ifp; 2451 out = fin->fin_out; 2452 flags = is->is_flags; 2453 sp = 0; 2454 dp = 0; 2455 2456 if (tcp != NULL) { 2457 sp = htons(fin->fin_sport); 2458 dp = ntohs(fin->fin_dport); 2459 } 2460 if (!rev) { 2461 if (tcp != NULL) { 2462 if (!(flags & SI_W_SPORT) && (sp != is->is_sport)) 2463 rev = 1; 2464 else if (!(flags & SI_W_DPORT) && (dp != is->is_dport)) 2465 rev = 1; 2466 } 2467 } 2468 2469 idx = (out << 1) + rev; 2470 2471 /* 2472 * If the interface for this 'direction' is set, make sure it matches. 2473 * An interface name that is not set matches any, as does a name of *. 2474 */ 2475 if ((is->is_ifp[idx] == ifp) || (is->is_ifp[idx] == NULL && 2476 (*is->is_ifname[idx] == '\0' || *is->is_ifname[idx] == '-' || 2477 *is->is_ifname[idx] == '*'))) 2478 ret = 1; 2479 2480 if (ret == 0) { 2481 DT2(iss_lookup_badifp, fr_info_t *, fin, ipstate_t *, is); 2482 SBUMP(ipf_state_stats.iss_lookup_badifp); 2483 /* TRACE is, out, rev, idx */ 2484 return NULL; 2485 } 2486 ret = 0; 2487 2488 /* 2489 * Match addresses and ports. 2490 */ 2491 if (rev == 0) { 2492 if ((IP6_EQ(&is->is_dst, dst) || (flags & SI_W_DADDR)) && 2493 (IP6_EQ(&is->is_src, src) || (flags & SI_W_SADDR))) { 2494 if (tcp) { 2495 if ((sp == is->is_sport || flags & SI_W_SPORT) 2496 && 2497 (dp == is->is_dport || flags & SI_W_DPORT)) 2498 ret = 1; 2499 } else { 2500 ret = 1; 2501 } 2502 } 2503 } else { 2504 if ((IP6_EQ(&is->is_dst, src) || (flags & SI_W_DADDR)) && 2505 (IP6_EQ(&is->is_src, dst) || (flags & SI_W_SADDR))) { 2506 if (tcp) { 2507 if ((dp == is->is_sport || flags & SI_W_SPORT) 2508 && 2509 (sp == is->is_dport || flags & SI_W_DPORT)) 2510 ret = 1; 2511 } else { 2512 ret = 1; 2513 } 2514 } 2515 } 2516 2517 if (ret == 0) { 2518 SBUMP(ipf_state_stats.iss_lookup_badport); 2519 DT2(iss_lookup_badport, fr_info_t *, fin, ipstate_t *, is); 2520 /* TRACE rev, is, sp, dp, src, dst */ 2521 return NULL; 2522 } 2523 2524 /* 2525 * Whether or not this should be here, is questionable, but the aim 2526 * is to get this out of the main line. 2527 */ 2528 if (tcp == NULL) 2529 flags = is->is_flags & ~(SI_WILDP|SI_NEWFR|SI_CLONE|SI_CLONED); 2530 2531 /* 2532 * Only one of the source or destination address can be flaged as a 2533 * wildcard. Fill in the missing address, if set. 2534 * For IPv6, if the address being copied in is multicast, then 2535 * don't reset the wild flag - multicast causes it to be set in the 2536 * first place! 2537 */ 2538 if ((flags & (SI_W_SADDR|SI_W_DADDR))) { 2539 fr_ip_t *fi = &fin->fin_fi; 2540 2541 if ((flags & SI_W_SADDR) != 0) { 2542 if (rev == 0) { 2543 is->is_src = fi->fi_src; 2544 is->is_flags &= ~SI_W_SADDR; 2545 } else { 2546 if (!(fin->fin_flx & (FI_MULTICAST|FI_MBCAST))){ 2547 is->is_src = fi->fi_dst; 2548 is->is_flags &= ~SI_W_SADDR; 2549 } 2550 } 2551 } else if ((flags & SI_W_DADDR) != 0) { 2552 if (rev == 0) { 2553 if (!(fin->fin_flx & (FI_MULTICAST|FI_MBCAST))){ 2554 is->is_dst = fi->fi_dst; 2555 is->is_flags &= ~SI_W_DADDR; 2556 } 2557 } else { 2558 is->is_dst = fi->fi_src; 2559 is->is_flags &= ~SI_W_DADDR; 2560 } 2561 } 2562 if ((is->is_flags & (SI_WILDA|SI_WILDP)) == 0) { 2563 ATOMIC_DECL(softs->ipf_state_stats.iss_wild); 2564 } 2565 } 2566 2567 flx = fin->fin_flx & cmask; 2568 cflx = is->is_flx[out][rev]; 2569 2570 /* 2571 * Match up any flags set from IP options. 2572 */ 2573 if ((cflx && (flx != (cflx & cmask))) || 2574 ((fin->fin_optmsk & is->is_optmsk[rev]) != is->is_opt[rev]) || 2575 ((fin->fin_secmsk & is->is_secmsk) != is->is_sec) || 2576 ((fin->fin_auth & is->is_authmsk) != is->is_auth)) { 2577 SBUMPD(ipf_state_stats, iss_miss_mask); 2578 return NULL; 2579 } 2580 2581 if ((fin->fin_flx & FI_IGNORE) != 0) { 2582 fin->fin_rev = rev; 2583 return is; 2584 } 2585 2586 /* 2587 * Only one of the source or destination port can be flagged as a 2588 * wildcard. When filling it in, fill in a copy of the matched entry 2589 * if it has the cloning flag set. 2590 */ 2591 if ((flags & (SI_W_SPORT|SI_W_DPORT))) { 2592 if ((flags & SI_CLONE) != 0) { 2593 ipstate_t *clone; 2594 2595 clone = ipf_state_clone(fin, tcp, is); 2596 if (clone == NULL) 2597 return NULL; 2598 is = clone; 2599 } else { 2600 ATOMIC_DECL(softs->ipf_state_stats.iss_wild); 2601 } 2602 2603 if ((flags & SI_W_SPORT) != 0) { 2604 if (rev == 0) { 2605 is->is_sport = sp; 2606 is->is_send = ntohl(tcp->th_seq); 2607 } else { 2608 is->is_sport = dp; 2609 is->is_send = ntohl(tcp->th_ack); 2610 } 2611 is->is_maxsend = is->is_send + 1; 2612 } else if ((flags & SI_W_DPORT) != 0) { 2613 if (rev == 0) { 2614 is->is_dport = dp; 2615 is->is_dend = ntohl(tcp->th_ack); 2616 } else { 2617 is->is_dport = sp; 2618 is->is_dend = ntohl(tcp->th_seq); 2619 } 2620 is->is_maxdend = is->is_dend + 1; 2621 } 2622 is->is_flags &= ~(SI_W_SPORT|SI_W_DPORT); 2623 if ((flags & SI_CLONED) && softs->ipf_state_logging) 2624 ipf_state_log(softc, is, ISL_CLONE); 2625 } 2626 2627 ret = -1; 2628 2629 if (is->is_flx[out][rev] == 0) { 2630 is->is_flx[out][rev] = flx; 2631 if (rev == 1 && is->is_optmsk[1] == 0) { 2632 is->is_opt[1] = fin->fin_optmsk; 2633 is->is_optmsk[1] = 0xffffffff; 2634 if (is->is_v == 6) { 2635 is->is_opt[1] &= ~0x8; 2636 is->is_optmsk[1] &= ~0x8; 2637 } 2638 } 2639 } 2640 2641 /* 2642 * Check if the interface name for this "direction" is set and if not, 2643 * fill it in. 2644 */ 2645 if (is->is_ifp[idx] == NULL && 2646 (*is->is_ifname[idx] == '\0' || *is->is_ifname[idx] == '*')) { 2647 is->is_ifp[idx] = ifp; 2648 COPYIFNAME(fin->fin_v, ifp, is->is_ifname[idx]); 2649 } 2650 fin->fin_rev = rev; 2651 return is; 2652} 2653 2654 2655/* ------------------------------------------------------------------------ */ 2656/* Function: ipf_checkicmpmatchingstate */ 2657/* Returns: Nil */ 2658/* Parameters: fin(I) - pointer to packet information */ 2659/* */ 2660/* If we've got an ICMP error message, using the information stored in the */ 2661/* ICMP packet, look for a matching state table entry. */ 2662/* */ 2663/* If we return NULL then no lock on ipf_state is held. */ 2664/* If we return non-null then a read-lock on ipf_state is held. */ 2665/* ------------------------------------------------------------------------ */ 2666static ipstate_t * 2667ipf_checkicmpmatchingstate(fin) 2668 fr_info_t *fin; 2669{ 2670 ipf_main_softc_t *softc = fin->fin_main_soft; 2671 ipf_state_softc_t *softs = softc->ipf_state_soft; 2672 ipstate_t *is, **isp; 2673 i6addr_t dst, src; 2674 struct icmp *ic; 2675 u_short savelen; 2676 icmphdr_t *icmp; 2677 fr_info_t ofin; 2678 tcphdr_t *tcp; 2679 int type, len; 2680 u_char pr; 2681 ip_t *oip; 2682 u_int hv; 2683 2684 /* 2685 * Does it at least have the return (basic) IP header ? 2686 * Is it an actual recognised ICMP error type? 2687 * Only a basic IP header (no options) should be with 2688 * an ICMP error header. 2689 */ 2690 if ((fin->fin_v != 4) || (fin->fin_hlen != sizeof(ip_t)) || 2691 (fin->fin_plen < ICMPERR_MINPKTLEN) || 2692 !(fin->fin_flx & FI_ICMPERR)) { 2693 SBUMPD(ipf_state_stats, iss_icmp_bad); 2694 return NULL; 2695 } 2696 ic = fin->fin_dp; 2697 type = ic->icmp_type; 2698 2699 oip = (ip_t *)((char *)ic + ICMPERR_ICMPHLEN); 2700 /* 2701 * Check if the at least the old IP header (with options) and 2702 * 8 bytes of payload is present. 2703 */ 2704 if (fin->fin_plen < ICMPERR_MAXPKTLEN + ((IP_HL(oip) - 5) << 2)) { 2705 SBUMPDX(ipf_state_stats, iss_icmp_short, iss_icmp_short_1); 2706 return NULL; 2707 } 2708 2709 /* 2710 * Sanity Checks. 2711 */ 2712 len = fin->fin_dlen - ICMPERR_ICMPHLEN; 2713 if ((len <= 0) || ((IP_HL(oip) << 2) > len)) { 2714 DT2(iss_icmp_len, fr_info_t *, fin, struct ip*, oip); 2715 SBUMPDX(ipf_state_stats, iss_icmp_short, iss_icmp_short_1); 2716 return NULL; 2717 } 2718 2719 /* 2720 * Is the buffer big enough for all of it ? It's the size of the IP 2721 * header claimed in the encapsulated part which is of concern. It 2722 * may be too big to be in this buffer but not so big that it's 2723 * outside the ICMP packet, leading to TCP deref's causing problems. 2724 * This is possible because we don't know how big oip_hl is when we 2725 * do the pullup early in ipf_check() and thus can't guarantee it is 2726 * all here now. 2727 */ 2728#ifdef _KERNEL 2729 { 2730 mb_t *m; 2731 2732 m = fin->fin_m; 2733# if defined(MENTAT) 2734 if ((char *)oip + len > (char *)m->b_wptr) { 2735 SBUMPDX(ipf_state_stats, iss_icmp_short, iss_icmp_short_2); 2736 return NULL; 2737 } 2738# else 2739 if ((char *)oip + len > (char *)fin->fin_ip + m->m_len) { 2740 SBUMPDX(ipf_state_stats, iss_icmp_short, iss_icmp_short_3); 2741 return NULL; 2742 } 2743# endif 2744 } 2745#endif 2746 2747 bcopy((char *)fin, (char *)&ofin, sizeof(*fin)); 2748 2749 /* 2750 * in the IPv4 case we must zero the i6addr union otherwise 2751 * the IP6_EQ and IP6_NEQ macros produce the wrong results because 2752 * of the 'junk' in the unused part of the union 2753 */ 2754 bzero((char *)&src, sizeof(src)); 2755 bzero((char *)&dst, sizeof(dst)); 2756 2757 /* 2758 * we make an fin entry to be able to feed it to 2759 * matchsrcdst note that not all fields are encessary 2760 * but this is the cleanest way. Note further we fill 2761 * in fin_mp such that if someone uses it we'll get 2762 * a kernel panic. ipf_matchsrcdst does not use this. 2763 * 2764 * watch out here, as ip is in host order and oip in network 2765 * order. Any change we make must be undone afterwards, like 2766 * oip->ip_len. 2767 */ 2768 savelen = oip->ip_len; 2769 oip->ip_len = htons(len); 2770 2771 ofin.fin_flx = FI_NOCKSUM; 2772 ofin.fin_v = 4; 2773 ofin.fin_ip = oip; 2774 ofin.fin_m = NULL; /* if dereferenced, panic XXX */ 2775 ofin.fin_mp = NULL; /* if dereferenced, panic XXX */ 2776 (void) ipf_makefrip(IP_HL(oip) << 2, oip, &ofin); 2777 ofin.fin_ifp = fin->fin_ifp; 2778 ofin.fin_out = !fin->fin_out; 2779 2780 hv = (pr = oip->ip_p); 2781 src.in4 = oip->ip_src; 2782 hv += src.in4.s_addr; 2783 dst.in4 = oip->ip_dst; 2784 hv += dst.in4.s_addr; 2785 2786 /* 2787 * Reset the short and bad flag here because in ipf_matchsrcdst() 2788 * the flags for the current packet (fin_flx) are compared against 2789 * those for the existing session. 2790 */ 2791 ofin.fin_flx &= ~(FI_BAD|FI_SHORT); 2792 2793 /* 2794 * Put old values of ip_len back as we don't know 2795 * if we have to forward the packet or process it again. 2796 */ 2797 oip->ip_len = savelen; 2798 2799 switch (oip->ip_p) 2800 { 2801 case IPPROTO_ICMP : 2802 /* 2803 * an ICMP error can only be generated as a result of an 2804 * ICMP query, not as the response on an ICMP error 2805 * 2806 * XXX theoretically ICMP_ECHOREP and the other reply's are 2807 * ICMP query's as well, but adding them here seems strange XXX 2808 */ 2809 if ((ofin.fin_flx & FI_ICMPERR) != 0) { 2810 DT1(iss_icmp_icmperr, fr_info_t *, &ofin); 2811 SBUMP(ipf_state_stats.iss_icmp_icmperr); 2812 return NULL; 2813 } 2814 2815 /* 2816 * perform a lookup of the ICMP packet in the state table 2817 */ 2818 icmp = (icmphdr_t *)((char *)oip + (IP_HL(oip) << 2)); 2819 hv += icmp->icmp_id; 2820 hv = DOUBLE_HASH(hv); 2821 2822 READ_ENTER(&softc->ipf_state); 2823 for (isp = &softs->ipf_state_table[hv]; 2824 ((is = *isp) != NULL); ) { 2825 isp = &is->is_hnext; 2826 if ((is->is_p != pr) || (is->is_v != 4)) 2827 continue; 2828 if (is->is_pass & FR_NOICMPERR) 2829 continue; 2830 2831 is = ipf_matchsrcdst(&ofin, is, &src, &dst, 2832 NULL, FI_ICMPCMP); 2833 if ((is != NULL) && !ipf_allowstateicmp(fin, is, &src)) 2834 return is; 2835 } 2836 RWLOCK_EXIT(&softc->ipf_state); 2837 SBUMPDX(ipf_state_stats, iss_icmp_miss, iss_icmp_miss_1); 2838 return NULL; 2839 case IPPROTO_TCP : 2840 case IPPROTO_UDP : 2841 break; 2842 default : 2843 SBUMPDX(ipf_state_stats, iss_icmp_miss, iss_icmp_miss_2); 2844 return NULL; 2845 } 2846 2847 tcp = (tcphdr_t *)((char *)oip + (IP_HL(oip) << 2)); 2848 2849 hv += tcp->th_dport;; 2850 hv += tcp->th_sport;; 2851 hv = DOUBLE_HASH(hv); 2852 2853 READ_ENTER(&softc->ipf_state); 2854 for (isp = &softs->ipf_state_table[hv]; ((is = *isp) != NULL); ) { 2855 isp = &is->is_hnext; 2856 /* 2857 * Only allow this icmp though if the 2858 * encapsulated packet was allowed through the 2859 * other way around. Note that the minimal amount 2860 * of info present does not allow for checking against 2861 * tcp internals such as seq and ack numbers. Only the 2862 * ports are known to be present and can be even if the 2863 * short flag is set. 2864 */ 2865 if ((is->is_p == pr) && (is->is_v == 4) && 2866 (is = ipf_matchsrcdst(&ofin, is, &src, &dst, 2867 tcp, FI_ICMPCMP))) { 2868 if (ipf_allowstateicmp(fin, is, &src) == 0) 2869 return is; 2870 } 2871 } 2872 RWLOCK_EXIT(&softc->ipf_state); 2873 SBUMPDX(ipf_state_stats, iss_icmp_miss, iss_icmp_miss_3); 2874 return NULL; 2875} 2876 2877 2878/* ------------------------------------------------------------------------ */ 2879/* Function: ipf_allowstateicmp */ 2880/* Returns: int - 1 = packet denied, 0 = packet allowed */ 2881/* Parameters: fin(I) - pointer to packet information */ 2882/* is(I) - pointer to state table entry */ 2883/* src(I) - source address to check permission for */ 2884/* */ 2885/* For an ICMP packet that has so far matched a state table entry, check if */ 2886/* there are any further refinements that might mean we want to block this */ 2887/* packet. This code isn't specific to either IPv4 or IPv6. */ 2888/* ------------------------------------------------------------------------ */ 2889static int 2890ipf_allowstateicmp(fin, is, src) 2891 fr_info_t *fin; 2892 ipstate_t *is; 2893 i6addr_t *src; 2894{ 2895 ipf_main_softc_t *softc = fin->fin_main_soft; 2896 ipf_state_softc_t *softs = softc->ipf_state_soft; 2897 frentry_t *savefr; 2898 frentry_t *fr; 2899 u_32_t ipass; 2900 int backward; 2901 int oi; 2902 int i; 2903 2904 fr = is->is_rule; 2905 if (fr != NULL && fr->fr_icmpgrp != NULL) { 2906 savefr = fin->fin_fr; 2907 fin->fin_fr = fr->fr_icmpgrp->fg_start; 2908 2909 ipass = ipf_scanlist(fin, softc->ipf_pass); 2910 fin->fin_fr = savefr; 2911 if (FR_ISBLOCK(ipass)) { 2912 SBUMPD(ipf_state_stats, iss_icmp_headblock); 2913 return 1; 2914 } 2915 } 2916 2917 /* 2918 * i : the index of this packet (the icmp unreachable) 2919 * oi : the index of the original packet found in the 2920 * icmp header (i.e. the packet causing this icmp) 2921 * backward : original packet was backward compared to 2922 * the state 2923 */ 2924 backward = IP6_NEQ(&is->is_src, src); 2925 fin->fin_rev = !backward; 2926 i = (!backward << 1) + fin->fin_out; 2927 oi = (backward << 1) + !fin->fin_out; 2928 2929 if (is->is_pass & FR_NOICMPERR) { 2930 SBUMPD(ipf_state_stats, iss_icmp_banned); 2931 return 1; 2932 } 2933 if (is->is_icmppkts[i] > is->is_pkts[oi]) { 2934 SBUMPD(ipf_state_stats, iss_icmp_toomany); 2935 return 1; 2936 } 2937 2938 DT2(iss_icmp_hits, fr_info_t *, fin, ipstate_t *, is); 2939 SBUMP(ipf_state_stats.iss_icmp_hits); 2940 is->is_icmppkts[i]++; 2941 2942 /* 2943 * we deliberately do not touch the timeouts 2944 * for the accompanying state table entry. 2945 * It remains to be seen if that is correct. XXX 2946 */ 2947 return 0; 2948} 2949 2950 2951/* ------------------------------------------------------------------------ */ 2952/* Function: ipf_ipsmove */ 2953/* Returns: Nil */ 2954/* Parameters: is(I) - pointer to state table entry */ 2955/* hv(I) - new hash value for state table entry */ 2956/* Write Locks: ipf_state */ 2957/* */ 2958/* Move a state entry from one position in the hash table to another. */ 2959/* ------------------------------------------------------------------------ */ 2960static void 2961ipf_ipsmove(softs, is, hv) 2962 ipf_state_softc_t *softs; 2963 ipstate_t *is; 2964 u_int hv; 2965{ 2966 ipstate_t **isp; 2967 u_int hvm; 2968 2969 hvm = is->is_hv; 2970 2971 /* TRACE is, is_hv, hvm */ 2972 2973 /* 2974 * Remove the hash from the old location... 2975 */ 2976 isp = is->is_phnext; 2977 if (is->is_hnext) 2978 is->is_hnext->is_phnext = isp; 2979 *isp = is->is_hnext; 2980 if (softs->ipf_state_table[hvm] == NULL) 2981 softs->ipf_state_stats.iss_inuse--; 2982 softs->ipf_state_stats.iss_bucketlen[hvm]--; 2983 2984 /* 2985 * ...and put the hash in the new one. 2986 */ 2987 hvm = DOUBLE_HASH(hv); 2988 is->is_hv = hvm; 2989 2990 /* TRACE is, hv, is_hv, hvm */ 2991 2992 isp = &softs->ipf_state_table[hvm]; 2993 if (*isp) 2994 (*isp)->is_phnext = &is->is_hnext; 2995 else 2996 softs->ipf_state_stats.iss_inuse++; 2997 softs->ipf_state_stats.iss_bucketlen[hvm]++; 2998 is->is_phnext = isp; 2999 is->is_hnext = *isp; 3000 *isp = is; 3001} 3002 3003 3004/* ------------------------------------------------------------------------ */ 3005/* Function: ipf_state_lookup */ 3006/* Returns: ipstate_t* - NULL == no matching state found, */ 3007/* else pointer to state information is returned */ 3008/* Parameters: fin(I) - pointer to packet information */ 3009/* tcp(I) - pointer to TCP/UDP header. */ 3010/* ifqp(O) - pointer for storing tailq timeout */ 3011/* */ 3012/* Search the state table for a matching entry to the packet described by */ 3013/* the contents of *fin. For certain protocols, when a match is found the */ 3014/* timeout queue is also selected and stored in ifpq if it is non-NULL. */ 3015/* */ 3016/* If we return NULL then no lock on ipf_state is held. */ 3017/* If we return non-null then a read-lock on ipf_state is held. */ 3018/* ------------------------------------------------------------------------ */ 3019ipstate_t * 3020ipf_state_lookup(fin, tcp, ifqp) 3021 fr_info_t *fin; 3022 tcphdr_t *tcp; 3023 ipftq_t **ifqp; 3024{ 3025 ipf_main_softc_t *softc = fin->fin_main_soft; 3026 ipf_state_softc_t *softs = softc->ipf_state_soft; 3027 u_int hv, hvm, pr, v, tryagain; 3028 ipstate_t *is, **isp; 3029 u_short dport, sport; 3030 i6addr_t src, dst; 3031 struct icmp *ic; 3032 ipftq_t *ifq; 3033 int oow; 3034 3035 is = NULL; 3036 ifq = NULL; 3037 tcp = fin->fin_dp; 3038 ic = (struct icmp *)tcp; 3039 hv = (pr = fin->fin_fi.fi_p); 3040 src = fin->fin_fi.fi_src; 3041 dst = fin->fin_fi.fi_dst; 3042 hv += src.in4.s_addr; 3043 hv += dst.in4.s_addr; 3044 3045 v = fin->fin_fi.fi_v; 3046#ifdef USE_INET6 3047 if (v == 6) { 3048 hv += fin->fin_fi.fi_src.i6[1]; 3049 hv += fin->fin_fi.fi_src.i6[2]; 3050 hv += fin->fin_fi.fi_src.i6[3]; 3051 3052 if ((fin->fin_p == IPPROTO_ICMPV6) && 3053 IN6_IS_ADDR_MULTICAST(&fin->fin_fi.fi_dst.in6)) { 3054 hv -= dst.in4.s_addr; 3055 } else { 3056 hv += fin->fin_fi.fi_dst.i6[1]; 3057 hv += fin->fin_fi.fi_dst.i6[2]; 3058 hv += fin->fin_fi.fi_dst.i6[3]; 3059 } 3060 } 3061#endif 3062 if ((v == 4) && 3063 (fin->fin_flx & (FI_MULTICAST|FI_BROADCAST|FI_MBCAST))) { 3064 if (fin->fin_out == 0) { 3065 hv -= src.in4.s_addr; 3066 } else { 3067 hv -= dst.in4.s_addr; 3068 } 3069 } 3070 3071 /* TRACE fin_saddr, fin_daddr, hv */ 3072 3073 /* 3074 * Search the hash table for matching packet header info. 3075 */ 3076 switch (pr) 3077 { 3078#ifdef USE_INET6 3079 case IPPROTO_ICMPV6 : 3080 tryagain = 0; 3081 if (v == 6) { 3082 if ((ic->icmp_type == ICMP6_ECHO_REQUEST) || 3083 (ic->icmp_type == ICMP6_ECHO_REPLY)) { 3084 hv += ic->icmp_id; 3085 } 3086 } 3087 READ_ENTER(&softc->ipf_state); 3088icmp6again: 3089 hvm = DOUBLE_HASH(hv); 3090 for (isp = &softs->ipf_state_table[hvm]; 3091 ((is = *isp) != NULL); ) { 3092 isp = &is->is_hnext; 3093 if ((is->is_p != pr) || (is->is_v != v)) 3094 continue; 3095 is = ipf_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP); 3096 if (is != NULL && 3097 ipf_matchicmpqueryreply(v, &is->is_icmp, 3098 ic, fin->fin_rev)) { 3099 if (fin->fin_rev) 3100 ifq = &softs->ipf_state_icmpacktq; 3101 else 3102 ifq = &softs->ipf_state_icmptq; 3103 break; 3104 } 3105 } 3106 3107 if (is != NULL) { 3108 if ((tryagain != 0) && !(is->is_flags & SI_W_DADDR)) { 3109 hv += fin->fin_fi.fi_src.i6[0]; 3110 hv += fin->fin_fi.fi_src.i6[1]; 3111 hv += fin->fin_fi.fi_src.i6[2]; 3112 hv += fin->fin_fi.fi_src.i6[3]; 3113 ipf_ipsmove(softs, is, hv); 3114 MUTEX_DOWNGRADE(&softc->ipf_state); 3115 } 3116 break; 3117 } 3118 RWLOCK_EXIT(&softc->ipf_state); 3119 3120 /* 3121 * No matching icmp state entry. Perhaps this is a 3122 * response to another state entry. 3123 * 3124 * XXX With some ICMP6 packets, the "other" address is already 3125 * in the packet, after the ICMP6 header, and this could be 3126 * used in place of the multicast address. However, taking 3127 * advantage of this requires some significant code changes 3128 * to handle the specific types where that is the case. 3129 */ 3130 if ((softs->ipf_state_stats.iss_wild != 0) && 3131 ((fin->fin_flx & FI_NOWILD) == 0) && 3132 (v == 6) && (tryagain == 0)) { 3133 hv -= fin->fin_fi.fi_src.i6[0]; 3134 hv -= fin->fin_fi.fi_src.i6[1]; 3135 hv -= fin->fin_fi.fi_src.i6[2]; 3136 hv -= fin->fin_fi.fi_src.i6[3]; 3137 tryagain = 1; 3138 WRITE_ENTER(&softc->ipf_state); 3139 goto icmp6again; 3140 } 3141 3142 is = ipf_checkicmp6matchingstate(fin); 3143 if (is != NULL) 3144 return is; 3145 break; 3146#endif 3147 3148 case IPPROTO_ICMP : 3149 if (v == 4) { 3150 hv += ic->icmp_id; 3151 } 3152 hv = DOUBLE_HASH(hv); 3153 READ_ENTER(&softc->ipf_state); 3154 for (isp = &softs->ipf_state_table[hv]; 3155 ((is = *isp) != NULL); ) { 3156 isp = &is->is_hnext; 3157 if ((is->is_p != pr) || (is->is_v != v)) 3158 continue; 3159 is = ipf_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP); 3160 if ((is != NULL) && 3161 (ic->icmp_id == is->is_icmp.ici_id) && 3162 ipf_matchicmpqueryreply(v, &is->is_icmp, 3163 ic, fin->fin_rev)) { 3164 if (fin->fin_rev) 3165 ifq = &softs->ipf_state_icmpacktq; 3166 else 3167 ifq = &softs->ipf_state_icmptq; 3168 break; 3169 } 3170 } 3171 if (is == NULL) { 3172 RWLOCK_EXIT(&softc->ipf_state); 3173 } 3174 break; 3175 3176 case IPPROTO_TCP : 3177 case IPPROTO_UDP : 3178 ifqp = NULL; 3179 sport = htons(fin->fin_data[0]); 3180 hv += sport; 3181 dport = htons(fin->fin_data[1]); 3182 hv += dport; 3183 oow = 0; 3184 tryagain = 0; 3185 READ_ENTER(&softc->ipf_state); 3186retry_tcpudp: 3187 hvm = DOUBLE_HASH(hv); 3188 3189 /* TRACE hv, hvm */ 3190 3191 for (isp = &softs->ipf_state_table[hvm]; 3192 ((is = *isp) != NULL); ) { 3193 isp = &is->is_hnext; 3194 if ((is->is_p != pr) || (is->is_v != v)) 3195 continue; 3196 fin->fin_flx &= ~FI_OOW; 3197 is = ipf_matchsrcdst(fin, is, &src, &dst, tcp, FI_CMP); 3198 if (is != NULL) { 3199 if (pr == IPPROTO_TCP) { 3200 if (!ipf_state_tcp(softc, softs, fin, 3201 tcp, is)) { 3202 oow |= fin->fin_flx & FI_OOW; 3203 continue; 3204 } 3205 } 3206 break; 3207 } 3208 } 3209 if (is != NULL) { 3210 if (tryagain && 3211 !(is->is_flags & (SI_CLONE|SI_WILDP|SI_WILDA))) { 3212 hv += dport; 3213 hv += sport; 3214 ipf_ipsmove(softs, is, hv); 3215 MUTEX_DOWNGRADE(&softc->ipf_state); 3216 } 3217 break; 3218 } 3219 RWLOCK_EXIT(&softc->ipf_state); 3220 3221 if ((softs->ipf_state_stats.iss_wild != 0) && 3222 ((fin->fin_flx & FI_NOWILD) == 0)) { 3223 if (tryagain == 0) { 3224 hv -= dport; 3225 hv -= sport; 3226 } else if (tryagain == 1) { 3227 hv = fin->fin_fi.fi_p; 3228 /* 3229 * If we try to pretend this is a reply to a 3230 * multicast/broadcast packet then we need to 3231 * exclude part of the address from the hash 3232 * calculation. 3233 */ 3234 if (fin->fin_out == 0) { 3235 hv += src.in4.s_addr; 3236 } else { 3237 hv += dst.in4.s_addr; 3238 } 3239 hv += dport; 3240 hv += sport; 3241 } 3242 tryagain++; 3243 if (tryagain <= 2) { 3244 WRITE_ENTER(&softc->ipf_state); 3245 goto retry_tcpudp; 3246 } 3247 } 3248 fin->fin_flx |= oow; 3249 break; 3250 3251#if 0 3252 case IPPROTO_GRE : 3253 gre = fin->fin_dp; 3254 if (GRE_REV(gre->gr_flags) == 1) { 3255 hv += gre->gr_call; 3256 } 3257 /* FALLTHROUGH */ 3258#endif 3259 default : 3260 ifqp = NULL; 3261 hvm = DOUBLE_HASH(hv); 3262 READ_ENTER(&softc->ipf_state); 3263 for (isp = &softs->ipf_state_table[hvm]; 3264 ((is = *isp) != NULL); ) { 3265 isp = &is->is_hnext; 3266 if ((is->is_p != pr) || (is->is_v != v)) 3267 continue; 3268 is = ipf_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP); 3269 if (is != NULL) { 3270 ifq = &softs->ipf_state_iptq; 3271 break; 3272 } 3273 } 3274 if (is == NULL) { 3275 RWLOCK_EXIT(&softc->ipf_state); 3276 } 3277 break; 3278 } 3279 3280 if (is != NULL) { 3281 if (((is->is_sti.tqe_flags & TQE_RULEBASED) != 0) && 3282 (is->is_tqehead[fin->fin_rev] != NULL)) 3283 ifq = is->is_tqehead[fin->fin_rev]; 3284 if (ifq != NULL && ifqp != NULL) 3285 *ifqp = ifq; 3286 } else { 3287 SBUMP(ipf_state_stats.iss_lookup_miss); 3288 } 3289 return is; 3290} 3291 3292 3293/* ------------------------------------------------------------------------ */ 3294/* Function: ipf_state_check */ 3295/* Returns: frentry_t* - NULL == search failed, */ 3296/* else pointer to rule for matching state */ 3297/* Parameters: fin(I) - pointer to packet information */ 3298/* passp(I) - pointer to filtering result flags */ 3299/* */ 3300/* Check if a packet is associated with an entry in the state table. */ 3301/* ------------------------------------------------------------------------ */ 3302frentry_t * 3303ipf_state_check(fin, passp) 3304 fr_info_t *fin; 3305 u_32_t *passp; 3306{ 3307 ipf_main_softc_t *softc = fin->fin_main_soft; 3308 ipf_state_softc_t *softs = softc->ipf_state_soft; 3309 ipftqent_t *tqe; 3310 ipstate_t *is; 3311 frentry_t *fr; 3312 tcphdr_t *tcp; 3313 ipftq_t *ifq; 3314 u_int pass; 3315 int inout; 3316 3317 if (softs->ipf_state_lock || (softs->ipf_state_list == NULL)) 3318 return NULL; 3319 3320 if (fin->fin_flx & (FI_SHORT|FI_FRAGBODY|FI_BAD)) { 3321 SBUMPD(ipf_state_stats, iss_check_bad); 3322 return NULL; 3323 } 3324 3325 if ((fin->fin_flx & FI_TCPUDP) || 3326 (fin->fin_fi.fi_p == IPPROTO_ICMP) 3327#ifdef USE_INET6 3328 || (fin->fin_fi.fi_p == IPPROTO_ICMPV6) 3329#endif 3330 ) 3331 tcp = fin->fin_dp; 3332 else 3333 tcp = NULL; 3334 3335 ifq = NULL; 3336 /* 3337 * Search the hash table for matching packet header info. 3338 */ 3339 is = ipf_state_lookup(fin, tcp, &ifq); 3340 3341 switch (fin->fin_p) 3342 { 3343#ifdef USE_INET6 3344 case IPPROTO_ICMPV6 : 3345 if (is != NULL) 3346 break; 3347 if (fin->fin_v == 6) { 3348 is = ipf_checkicmp6matchingstate(fin); 3349 } 3350 break; 3351#endif 3352 case IPPROTO_ICMP : 3353 if (is != NULL) 3354 break; 3355 /* 3356 * No matching icmp state entry. Perhaps this is a 3357 * response to another state entry. 3358 */ 3359 is = ipf_checkicmpmatchingstate(fin); 3360 break; 3361 3362 case IPPROTO_TCP : 3363 if (is == NULL) 3364 break; 3365 3366 if (is->is_pass & FR_NEWISN) { 3367 if (fin->fin_out == 0) 3368 ipf_fixinisn(fin, is); 3369 else if (fin->fin_out == 1) 3370 ipf_fixoutisn(fin, is); 3371 } 3372 break; 3373 default : 3374 if (fin->fin_rev) 3375 ifq = &softs->ipf_state_udpacktq; 3376 else 3377 ifq = &softs->ipf_state_udptq; 3378 break; 3379 } 3380 if (is == NULL) { 3381 SBUMP(ipf_state_stats.iss_check_miss); 3382 return NULL; 3383 } 3384 3385 fr = is->is_rule; 3386 if (fr != NULL) { 3387 if ((fin->fin_out == 0) && (fr->fr_nattag.ipt_num[0] != 0)) { 3388 if (fin->fin_nattag == NULL) { 3389 RWLOCK_EXIT(&softc->ipf_state); 3390 SBUMPD(ipf_state_stats, iss_check_notag); 3391 return NULL; 3392 } 3393 if (ipf_matchtag(&fr->fr_nattag, fin->fin_nattag)!=0) { 3394 RWLOCK_EXIT(&softc->ipf_state); 3395 SBUMPD(ipf_state_stats, iss_check_nattag); 3396 return NULL; 3397 } 3398 } 3399 (void) strncpy(fin->fin_group, FR_NAME(fr, fr_group), 3400 FR_GROUPLEN); 3401 fin->fin_icode = fr->fr_icode; 3402 } 3403 3404 fin->fin_rule = is->is_rulen; 3405 fin->fin_fr = fr; 3406 3407 /* 3408 * If this packet is a fragment and the rule says to track fragments, 3409 * then create a new fragment cache entry. 3410 */ 3411 if ((fin->fin_flx & FI_FRAG) && FR_ISPASS(is->is_pass)) 3412 (void) ipf_frag_new(softc, fin, is->is_pass); 3413 3414 /* 3415 * For TCP packets, ifq == NULL. For all others, check if this new 3416 * queue is different to the last one it was on and move it if so. 3417 */ 3418 tqe = &is->is_sti; 3419 if ((tqe->tqe_flags & TQE_RULEBASED) != 0) 3420 ifq = is->is_tqehead[fin->fin_rev]; 3421 3422 MUTEX_ENTER(&is->is_lock); 3423 3424 if (ifq != NULL) 3425 ipf_movequeue(softc->ipf_ticks, tqe, tqe->tqe_ifq, ifq); 3426 3427 inout = (fin->fin_rev << 1) + fin->fin_out; 3428 is->is_pkts[inout]++; 3429 is->is_bytes[inout] += fin->fin_plen; 3430 fin->fin_pktnum = is->is_pkts[inout] + is->is_icmppkts[inout]; 3431 3432 MUTEX_EXIT(&is->is_lock); 3433 3434 pass = is->is_pass; 3435 3436 if (is->is_flags & IS_STATESYNC) 3437 ipf_sync_update(softc, SMC_STATE, fin, is->is_sync); 3438 3439 RWLOCK_EXIT(&softc->ipf_state); 3440 3441 SBUMP(ipf_state_stats.iss_hits); 3442 3443 fin->fin_dif = &is->is_dif; 3444 fin->fin_tif = &is->is_tifs[fin->fin_rev]; 3445 fin->fin_flx |= FI_STATE; 3446 if ((pass & FR_LOGFIRST) != 0) 3447 pass &= ~(FR_LOGFIRST|FR_LOG); 3448 *passp = pass; 3449 return fr; 3450} 3451 3452 3453/* ------------------------------------------------------------------------ */ 3454/* Function: ipf_fixoutisn */ 3455/* Returns: Nil */ 3456/* Parameters: fin(I) - pointer to packet information */ 3457/* is(I) - pointer to master state structure */ 3458/* */ 3459/* Called only for outbound packets, adjusts the sequence number and the */ 3460/* TCP checksum to match that change. */ 3461/* ------------------------------------------------------------------------ */ 3462static void 3463ipf_fixoutisn(fin, is) 3464 fr_info_t *fin; 3465 ipstate_t *is; 3466{ 3467 tcphdr_t *tcp; 3468 int rev; 3469 u_32_t seq; 3470 3471 tcp = fin->fin_dp; 3472 rev = fin->fin_rev; 3473 if ((is->is_flags & IS_ISNSYN) != 0) { 3474 if ((rev == 0) && (fin->fin_cksum < FI_CK_L4PART)) { 3475 seq = ntohl(tcp->th_seq); 3476 seq += is->is_isninc[0]; 3477 tcp->th_seq = htonl(seq); 3478 ipf_fix_outcksum(0, &tcp->th_sum, is->is_sumd[0], 0); 3479 } 3480 } 3481 if ((is->is_flags & IS_ISNACK) != 0) { 3482 if ((rev == 1) && (fin->fin_cksum < FI_CK_L4PART)) { 3483 seq = ntohl(tcp->th_seq); 3484 seq += is->is_isninc[1]; 3485 tcp->th_seq = htonl(seq); 3486 ipf_fix_outcksum(0, &tcp->th_sum, is->is_sumd[1], 0); 3487 } 3488 } 3489} 3490 3491 3492/* ------------------------------------------------------------------------ */ 3493/* Function: ipf_fixinisn */ 3494/* Returns: Nil */ 3495/* Parameters: fin(I) - pointer to packet information */ 3496/* is(I) - pointer to master state structure */ 3497/* */ 3498/* Called only for inbound packets, adjusts the acknowledge number and the */ 3499/* TCP checksum to match that change. */ 3500/* ------------------------------------------------------------------------ */ 3501static void 3502ipf_fixinisn(fin, is) 3503 fr_info_t *fin; 3504 ipstate_t *is; 3505{ 3506 tcphdr_t *tcp; 3507 int rev; 3508 u_32_t ack; 3509 3510 tcp = fin->fin_dp; 3511 rev = fin->fin_rev; 3512 if ((is->is_flags & IS_ISNSYN) != 0) { 3513 if ((rev == 1) && (fin->fin_cksum < FI_CK_L4PART)) { 3514 ack = ntohl(tcp->th_ack); 3515 ack -= is->is_isninc[0]; 3516 tcp->th_ack = htonl(ack); 3517 ipf_fix_incksum(0, &tcp->th_sum, is->is_sumd[0], 0); 3518 } 3519 } 3520 if ((is->is_flags & IS_ISNACK) != 0) { 3521 if ((rev == 0) && (fin->fin_cksum < FI_CK_L4PART)) { 3522 ack = ntohl(tcp->th_ack); 3523 ack -= is->is_isninc[1]; 3524 tcp->th_ack = htonl(ack); 3525 ipf_fix_incksum(0, &tcp->th_sum, is->is_sumd[1], 0); 3526 } 3527 } 3528} 3529 3530 3531/* ------------------------------------------------------------------------ */ 3532/* Function: ipf_state_sync */ 3533/* Returns: Nil */ 3534/* Parameters: softc(I) - pointer to soft context main structure */ 3535/* ifp(I) - pointer to interface */ 3536/* */ 3537/* Walk through all state entries and if an interface pointer match is */ 3538/* found then look it up again, based on its name in case the pointer has */ 3539/* changed since last time. */ 3540/* */ 3541/* If ifp is passed in as being non-null then we are only doing updates for */ 3542/* existing, matching, uses of it. */ 3543/* ------------------------------------------------------------------------ */ 3544void 3545ipf_state_sync(softc, ifp) 3546 ipf_main_softc_t *softc; 3547 void *ifp; 3548{ 3549 ipf_state_softc_t *softs = softc->ipf_state_soft; 3550 ipstate_t *is; 3551 int i; 3552 3553 if (softc->ipf_running <= 0) 3554 return; 3555 3556 WRITE_ENTER(&softc->ipf_state); 3557 3558 if (softc->ipf_running <= 0) { 3559 RWLOCK_EXIT(&softc->ipf_state); 3560 return; 3561 } 3562 3563 for (is = softs->ipf_state_list; is; is = is->is_next) { 3564 /* 3565 * Look up all the interface names in the state entry. 3566 */ 3567 for (i = 0; i < 4; i++) { 3568 if (ifp == NULL || ifp == is->is_ifp[i]) 3569 is->is_ifp[i] = ipf_resolvenic(softc, 3570 is->is_ifname[i], 3571 is->is_v); 3572 } 3573 } 3574 RWLOCK_EXIT(&softc->ipf_state); 3575} 3576 3577 3578/* ------------------------------------------------------------------------ */ 3579/* Function: ipf_state_del */ 3580/* Returns: int - 0 = deleted, else refernce count on active struct */ 3581/* Parameters: softc(I) - pointer to soft context main structure */ 3582/* is(I) - pointer to state structure to delete */ 3583/* why(I) - if not 0, log reason why it was deleted */ 3584/* Write Locks: ipf_state */ 3585/* */ 3586/* Deletes a state entry from the enumerated list as well as the hash table */ 3587/* and timeout queue lists. Make adjustments to hash table statistics and */ 3588/* global counters as required. */ 3589/* ------------------------------------------------------------------------ */ 3590static int 3591ipf_state_del(softc, is, why) 3592 ipf_main_softc_t *softc; 3593 ipstate_t *is; 3594 int why; 3595{ 3596 ipf_state_softc_t *softs = softc->ipf_state_soft; 3597 int orphan = 1; 3598 frentry_t *fr; 3599 3600 /* 3601 * Since we want to delete this, remove it from the state table, 3602 * where it can be found & used, first. 3603 */ 3604 if (is->is_phnext != NULL) { 3605 *is->is_phnext = is->is_hnext; 3606 if (is->is_hnext != NULL) 3607 is->is_hnext->is_phnext = is->is_phnext; 3608 if (softs->ipf_state_table[is->is_hv] == NULL) 3609 softs->ipf_state_stats.iss_inuse--; 3610 softs->ipf_state_stats.iss_bucketlen[is->is_hv]--; 3611 3612 is->is_phnext = NULL; 3613 is->is_hnext = NULL; 3614 orphan = 0; 3615 } 3616 3617 /* 3618 * Because ipf_state_stats.iss_wild is a count of entries in the state 3619 * table that have wildcard flags set, only decerement it once 3620 * and do it here. 3621 */ 3622 if (is->is_flags & (SI_WILDP|SI_WILDA)) { 3623 if (!(is->is_flags & SI_CLONED)) { 3624 ATOMIC_DECL(softs->ipf_state_stats.iss_wild); 3625 } 3626 is->is_flags &= ~(SI_WILDP|SI_WILDA); 3627 } 3628 3629 /* 3630 * Next, remove it from the timeout queue it is in. 3631 */ 3632 if (is->is_sti.tqe_ifq != NULL) 3633 ipf_deletequeueentry(&is->is_sti); 3634 3635 /* 3636 * If it is still in use by something else, do not go any further, 3637 * but note that at this point it is now an orphan. How can this 3638 * be? ipf_state_flush() calls ipf_delete() directly because it wants 3639 * to empty the table out and if something has a hold on a state 3640 * entry (such as ipfstat), it'll do the deref path that'll bring 3641 * us back here to do the real delete & free. 3642 */ 3643 MUTEX_ENTER(&is->is_lock); 3644 if (is->is_me != NULL) { 3645 *is->is_me = NULL; 3646 is->is_me = NULL; 3647 is->is_ref--; 3648 } 3649 if (is->is_ref > 1) { 3650 int refs; 3651 3652 is->is_ref--; 3653 refs = is->is_ref; 3654 MUTEX_EXIT(&is->is_lock); 3655 if (!orphan) 3656 softs->ipf_state_stats.iss_orphan++; 3657 return refs; 3658 } 3659 MUTEX_EXIT(&is->is_lock); 3660 3661 fr = is->is_rule; 3662 is->is_rule = NULL; 3663 if (fr != NULL) { 3664 if (fr->fr_srctrack.ht_max_nodes != 0) { 3665 (void) ipf_ht_node_del(&fr->fr_srctrack, 3666 is->is_family, &is->is_src); 3667 } 3668 } 3669 3670 is->is_ref = 0; 3671 3672 if (is->is_tqehead[0] != NULL) { 3673 if (ipf_deletetimeoutqueue(is->is_tqehead[0]) == 0) 3674 ipf_freetimeoutqueue(softc, is->is_tqehead[0]); 3675 } 3676 if (is->is_tqehead[1] != NULL) { 3677 if (ipf_deletetimeoutqueue(is->is_tqehead[1]) == 0) 3678 ipf_freetimeoutqueue(softc, is->is_tqehead[1]); 3679 } 3680 3681 if (is->is_sync) 3682 ipf_sync_del_state(softc->ipf_sync_soft, is->is_sync); 3683 3684 /* 3685 * Now remove it from the linked list of known states 3686 */ 3687 if (is->is_pnext != NULL) { 3688 *is->is_pnext = is->is_next; 3689 3690 if (is->is_next != NULL) 3691 is->is_next->is_pnext = is->is_pnext; 3692 3693 is->is_pnext = NULL; 3694 is->is_next = NULL; 3695 } 3696 3697 if (softs->ipf_state_logging != 0 && why != 0) 3698 ipf_state_log(softc, is, why); 3699 3700 if (is->is_p == IPPROTO_TCP) 3701 softs->ipf_state_stats.iss_fin++; 3702 else 3703 softs->ipf_state_stats.iss_expire++; 3704 if (orphan) 3705 softs->ipf_state_stats.iss_orphan--; 3706 3707 if (fr != NULL) { 3708 fr->fr_statecnt--; 3709 (void) ipf_derefrule(softc, &fr); 3710 } 3711 3712 softs->ipf_state_stats.iss_active_proto[is->is_p]--; 3713 3714 MUTEX_DESTROY(&is->is_lock); 3715 KFREE(is); 3716 softs->ipf_state_stats.iss_active--; 3717 3718 return 0; 3719} 3720 3721 3722/* ------------------------------------------------------------------------ */ 3723/* Function: ipf_state_expire */ 3724/* Returns: Nil */ 3725/* Parameters: softc(I) - pointer to soft context main structure */ 3726/* */ 3727/* Slowly expire held state for thingslike UDP and ICMP. The algorithm */ 3728/* used here is to keep the queue sorted with the oldest things at the top */ 3729/* and the youngest at the bottom. So if the top one doesn't need to be */ 3730/* expired then neither will any under it. */ 3731/* ------------------------------------------------------------------------ */ 3732void 3733ipf_state_expire(softc) 3734 ipf_main_softc_t *softc; 3735{ 3736 ipf_state_softc_t *softs = softc->ipf_state_soft; 3737 ipftq_t *ifq, *ifqnext; 3738 ipftqent_t *tqe, *tqn; 3739 ipstate_t *is; 3740 SPL_INT(s); 3741 3742 SPL_NET(s); 3743 WRITE_ENTER(&softc->ipf_state); 3744 for (ifq = softs->ipf_state_tcptq; ifq != NULL; ifq = ifq->ifq_next) 3745 for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) { 3746 if (tqe->tqe_die > softc->ipf_ticks) 3747 break; 3748 tqn = tqe->tqe_next; 3749 is = tqe->tqe_parent; 3750 ipf_state_del(softc, is, ISL_EXPIRE); 3751 } 3752 3753 for (ifq = softs->ipf_state_usertq; ifq != NULL; ifq = ifqnext) { 3754 ifqnext = ifq->ifq_next; 3755 3756 for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) { 3757 if (tqe->tqe_die > softc->ipf_ticks) 3758 break; 3759 tqn = tqe->tqe_next; 3760 is = tqe->tqe_parent; 3761 ipf_state_del(softc, is, ISL_EXPIRE); 3762 } 3763 } 3764 3765 for (ifq = softs->ipf_state_usertq; ifq != NULL; ifq = ifqnext) { 3766 ifqnext = ifq->ifq_next; 3767 3768 if (((ifq->ifq_flags & IFQF_DELETE) != 0) && 3769 (ifq->ifq_ref == 0)) { 3770 ipf_freetimeoutqueue(softc, ifq); 3771 } 3772 } 3773 3774 if (softs->ipf_state_doflush) { 3775 (void) ipf_state_flush(softc, 2, 0); 3776 softs->ipf_state_doflush = 0; 3777 softs->ipf_state_wm_last = softc->ipf_ticks; 3778 } 3779 3780 RWLOCK_EXIT(&softc->ipf_state); 3781 SPL_X(s); 3782} 3783 3784 3785/* ------------------------------------------------------------------------ */ 3786/* Function: ipf_state_flush */ 3787/* Returns: int - 0 == success, -1 == failure */ 3788/* Parameters: softc(I) - pointer to soft context main structure */ 3789/* which(I) - which flush action to perform */ 3790/* proto(I) - which protocol to flush (0 == ALL) */ 3791/* Write Locks: ipf_state */ 3792/* */ 3793/* Flush state tables. Three actions currently defined: */ 3794/* which == 0 : flush all state table entries */ 3795/* which == 1 : flush TCP connections which have started to close but are */ 3796/* stuck for some reason. */ 3797/* which == 2 : flush TCP connections which have been idle for a long time, */ 3798/* starting at > 4 days idle and working back in successive half-*/ 3799/* days to at most 12 hours old. If this fails to free enough */ 3800/* slots then work backwards in half hour slots to 30 minutes. */ 3801/* If that too fails, then work backwards in 30 second intervals */ 3802/* for the last 30 minutes to at worst 30 seconds idle. */ 3803/* ------------------------------------------------------------------------ */ 3804int 3805ipf_state_flush(softc, which, proto) 3806 ipf_main_softc_t *softc; 3807 int which, proto; 3808{ 3809 ipf_state_softc_t *softs = softc->ipf_state_soft; 3810 ipftqent_t *tqe, *tqn; 3811 ipstate_t *is, **isp; 3812 ipftq_t *ifq; 3813 int removed; 3814 SPL_INT(s); 3815 3816 removed = 0; 3817 3818 SPL_NET(s); 3819 3820 switch (which) 3821 { 3822 case 0 : 3823 SBUMP(ipf_state_stats.iss_flush_all); 3824 /* 3825 * Style 0 flush removes everything... 3826 */ 3827 for (isp = &softs->ipf_state_list; ((is = *isp) != NULL); ) { 3828 if ((proto != 0) && (is->is_v != proto)) { 3829 isp = &is->is_next; 3830 continue; 3831 } 3832 if (ipf_state_del(softc, is, ISL_FLUSH) == 0) 3833 removed++; 3834 else 3835 isp = &is->is_next; 3836 } 3837 break; 3838 3839 case 1 : 3840 SBUMP(ipf_state_stats.iss_flush_closing); 3841 /* 3842 * Since we're only interested in things that are closing, 3843 * we can start with the appropriate timeout queue. 3844 */ 3845 for (ifq = softs->ipf_state_tcptq + IPF_TCPS_CLOSE_WAIT; 3846 ifq != NULL; ifq = ifq->ifq_next) { 3847 3848 for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) { 3849 tqn = tqe->tqe_next; 3850 is = tqe->tqe_parent; 3851 if (is->is_p != IPPROTO_TCP) 3852 break; 3853 if (ipf_state_del(softc, is, ISL_FLUSH) == 0) 3854 removed++; 3855 } 3856 } 3857 3858 /* 3859 * Also need to look through the user defined queues. 3860 */ 3861 for (ifq = softs->ipf_state_usertq; ifq != NULL; 3862 ifq = ifq->ifq_next) { 3863 for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) { 3864 tqn = tqe->tqe_next; 3865 is = tqe->tqe_parent; 3866 if (is->is_p != IPPROTO_TCP) 3867 continue; 3868 3869 if ((is->is_state[0] > IPF_TCPS_ESTABLISHED) && 3870 (is->is_state[1] > IPF_TCPS_ESTABLISHED)) { 3871 if (ipf_state_del(softc, is, 3872 ISL_FLUSH) == 0) 3873 removed++; 3874 } 3875 } 3876 } 3877 break; 3878 3879 case 2 : 3880 break; 3881 3882 /* 3883 * Args 5-11 correspond to flushing those particular states 3884 * for TCP connections. 3885 */ 3886 case IPF_TCPS_CLOSE_WAIT : 3887 case IPF_TCPS_FIN_WAIT_1 : 3888 case IPF_TCPS_CLOSING : 3889 case IPF_TCPS_LAST_ACK : 3890 case IPF_TCPS_FIN_WAIT_2 : 3891 case IPF_TCPS_TIME_WAIT : 3892 case IPF_TCPS_CLOSED : 3893 SBUMP(ipf_state_stats.iss_flush_queue); 3894 tqn = softs->ipf_state_tcptq[which].ifq_head; 3895 while (tqn != NULL) { 3896 tqe = tqn; 3897 tqn = tqe->tqe_next; 3898 is = tqe->tqe_parent; 3899 if (ipf_state_del(softc, is, ISL_FLUSH) == 0) 3900 removed++; 3901 } 3902 break; 3903 3904 default : 3905 if (which < 30) 3906 break; 3907 3908 SBUMP(ipf_state_stats.iss_flush_state); 3909 /* 3910 * Take a large arbitrary number to mean the number of seconds 3911 * for which which consider to be the maximum value we'll allow 3912 * the expiration to be. 3913 */ 3914 which = IPF_TTLVAL(which); 3915 for (isp = &softs->ipf_state_list; ((is = *isp) != NULL); ) { 3916 if ((proto == 0) || (is->is_v == proto)) { 3917 if (softc->ipf_ticks - is->is_touched > which) { 3918 if (ipf_state_del(softc, is, 3919 ISL_FLUSH) == 0) { 3920 removed++; 3921 continue; 3922 } 3923 } 3924 } 3925 isp = &is->is_next; 3926 } 3927 break; 3928 } 3929 3930 if (which != 2) { 3931 SPL_X(s); 3932 return removed; 3933 } 3934 3935 SBUMP(ipf_state_stats.iss_flush_timeout); 3936 /* 3937 * Asked to remove inactive entries because the table is full, try 3938 * again, 3 times, if first attempt failed with a different criteria 3939 * each time. The order tried in must be in decreasing age. 3940 * Another alternative is to implement random drop and drop N entries 3941 * at random until N have been freed up. 3942 */ 3943 if (softc->ipf_ticks - softs->ipf_state_wm_last > 3944 softs->ipf_state_wm_freq) { 3945 removed = ipf_queueflush(softc, ipf_state_flush_entry, 3946 softs->ipf_state_tcptq, 3947 softs->ipf_state_usertq, 3948 &softs->ipf_state_stats.iss_active, 3949 softs->ipf_state_size, 3950 softs->ipf_state_wm_low); 3951 softs->ipf_state_wm_last = softc->ipf_ticks; 3952 } 3953 3954 SPL_X(s); 3955 return removed; 3956} 3957 3958 3959/* ------------------------------------------------------------------------ */ 3960/* Function: ipf_state_flush_entry */ 3961/* Returns: int - 0 = entry deleted, else not deleted */ 3962/* Parameters: softc(I) - pointer to soft context main structure */ 3963/* entry(I) - pointer to state structure to delete */ 3964/* Write Locks: ipf_state */ 3965/* */ 3966/* This function is a stepping stone between ipf_queueflush() and */ 3967/* ipf_state_del(). It is used so we can provide a uniform interface via */ 3968/* the ipf_queueflush() function. */ 3969/* ------------------------------------------------------------------------ */ 3970static int 3971ipf_state_flush_entry(softc, entry) 3972 ipf_main_softc_t *softc; 3973 void *entry; 3974{ 3975 return ipf_state_del(softc, entry, ISL_FLUSH); 3976} 3977 3978 3979/* ------------------------------------------------------------------------ */ 3980/* Function: ipf_tcp_age */ 3981/* Returns: int - 1 == state transition made, 0 == no change (rejected) */ 3982/* Parameters: tqe(I) - pointer to timeout queue information */ 3983/* fin(I) - pointer to packet information */ 3984/* tqtab(I) - TCP timeout queue table this is in */ 3985/* flags(I) - flags from state/NAT entry */ 3986/* ok(I) - can we advance state */ 3987/* */ 3988/* Rewritten by Arjan de Vet <Arjan.deVet@adv.iae.nl>, 2000-07-29: */ 3989/* */ 3990/* - (try to) base state transitions on real evidence only, */ 3991/* i.e. packets that are sent and have been received by ipfilter; */ 3992/* diagram 18.12 of TCP/IP volume 1 by W. Richard Stevens was used. */ 3993/* */ 3994/* - deal with half-closed connections correctly; */ 3995/* */ 3996/* - store the state of the source in state[0] such that ipfstat */ 3997/* displays the state as source/dest instead of dest/source; the calls */ 3998/* to ipf_tcp_age have been changed accordingly. */ 3999/* */ 4000/* Internal Parameters: */ 4001/* */ 4002/* state[0] = state of source (host that initiated connection) */ 4003/* state[1] = state of dest (host that accepted the connection) */ 4004/* */ 4005/* dir == 0 : a packet from source to dest */ 4006/* dir == 1 : a packet from dest to source */ 4007/* */ 4008/* A typical procession for a connection is as follows: */ 4009/* */ 4010/* +--------------+-------------------+ */ 4011/* | Side '0' | Side '1' | */ 4012/* +--------------+-------------------+ */ 4013/* | 0 -> 1 (SYN) | | */ 4014/* | | 0 -> 2 (SYN-ACK) | */ 4015/* | 1 -> 3 (ACK) | | */ 4016/* | | 2 -> 4 (ACK-PUSH) | */ 4017/* | 3 -> 4 (ACK) | | */ 4018/* | ... | ... | */ 4019/* | | 4 -> 6 (FIN-ACK) | */ 4020/* | 4 -> 5 (ACK) | | */ 4021/* | | 6 -> 6 (ACK-PUSH) | */ 4022/* | 5 -> 5 (ACK) | | */ 4023/* | 5 -> 8 (FIN) | | */ 4024/* | | 6 -> 10 (ACK) | */ 4025/* +--------------+-------------------+ */ 4026/* */ 4027/* Locking: it is assumed that the parent of the tqe structure is locked. */ 4028/* ------------------------------------------------------------------------ */ 4029int 4030ipf_tcp_age(tqe, fin, tqtab, flags, ok) 4031 ipftqent_t *tqe; 4032 fr_info_t *fin; 4033 ipftq_t *tqtab; 4034 int flags, ok; 4035{ 4036 ipf_main_softc_t *softc = fin->fin_main_soft; 4037 int dlen, ostate, nstate, rval, dir; 4038 u_char tcpflags; 4039 tcphdr_t *tcp; 4040 4041 tcp = fin->fin_dp; 4042 4043 rval = 0; 4044 dir = fin->fin_rev; 4045 tcpflags = tcp->th_flags; 4046 dlen = fin->fin_dlen - (TCP_OFF(tcp) << 2); 4047 ostate = tqe->tqe_state[1 - dir]; 4048 nstate = tqe->tqe_state[dir]; 4049 4050 if (tcpflags & TH_RST) { 4051 if (!(tcpflags & TH_PUSH) && !dlen) 4052 nstate = IPF_TCPS_CLOSED; 4053 else 4054 nstate = IPF_TCPS_CLOSE_WAIT; 4055 4056 if (ostate <= IPF_TCPS_ESTABLISHED) { 4057 tqe->tqe_state[1 - dir] = IPF_TCPS_CLOSE_WAIT; 4058 } 4059 rval = 1; 4060 } else { 4061 switch (nstate) 4062 { 4063 case IPF_TCPS_LISTEN: /* 0 */ 4064 if ((tcpflags & TH_OPENING) == TH_OPENING) { 4065 /* 4066 * 'dir' received an S and sends SA in 4067 * response, LISTEN -> SYN_RECEIVED 4068 */ 4069 nstate = IPF_TCPS_SYN_RECEIVED; 4070 rval = 1; 4071 } else if ((tcpflags & TH_OPENING) == TH_SYN) { 4072 /* 'dir' sent S, LISTEN -> SYN_SENT */ 4073 nstate = IPF_TCPS_SYN_SENT; 4074 rval = 1; 4075 } 4076 /* 4077 * the next piece of code makes it possible to get 4078 * already established connections into the state table 4079 * after a restart or reload of the filter rules; this 4080 * does not work when a strict 'flags S keep state' is 4081 * used for tcp connections of course 4082 */ 4083 if (((flags & IS_TCPFSM) == 0) && 4084 ((tcpflags & TH_ACKMASK) == TH_ACK)) { 4085 /* 4086 * we saw an A, guess 'dir' is in ESTABLISHED 4087 * mode 4088 */ 4089 switch (ostate) 4090 { 4091 case IPF_TCPS_LISTEN : 4092 case IPF_TCPS_SYN_RECEIVED : 4093 nstate = IPF_TCPS_HALF_ESTAB; 4094 rval = 1; 4095 break; 4096 case IPF_TCPS_HALF_ESTAB : 4097 case IPF_TCPS_ESTABLISHED : 4098 nstate = IPF_TCPS_ESTABLISHED; 4099 rval = 1; 4100 break; 4101 default : 4102 break; 4103 } 4104 } 4105 /* 4106 * TODO: besides regular ACK packets we can have other 4107 * packets as well; it is yet to be determined how we 4108 * should initialize the states in those cases 4109 */ 4110 break; 4111 4112 case IPF_TCPS_SYN_SENT: /* 1 */ 4113 if ((tcpflags & ~(TH_ECN|TH_CWR)) == TH_SYN) { 4114 /* 4115 * A retransmitted SYN packet. We do not reset 4116 * the timeout here to ipf_tcptimeout because a 4117 * connection connect timeout does not renew 4118 * after every packet that is sent. We need to 4119 * set rval so as to indicate the packet has 4120 * passed the check for its flags being valid 4121 * in the TCP FSM. Setting rval to 2 has the 4122 * result of not resetting the timeout. 4123 */ 4124 rval = 2; 4125 } else if ((tcpflags & (TH_SYN|TH_FIN|TH_ACK)) == 4126 TH_ACK) { 4127 /* 4128 * we see an A from 'dir' which is in SYN_SENT 4129 * state: 'dir' sent an A in response to an SA 4130 * which it received, SYN_SENT -> ESTABLISHED 4131 */ 4132 nstate = IPF_TCPS_ESTABLISHED; 4133 rval = 1; 4134 } else if (tcpflags & TH_FIN) { 4135 /* 4136 * we see an F from 'dir' which is in SYN_SENT 4137 * state and wants to close its side of the 4138 * connection; SYN_SENT -> FIN_WAIT_1 4139 */ 4140 nstate = IPF_TCPS_FIN_WAIT_1; 4141 rval = 1; 4142 } else if ((tcpflags & TH_OPENING) == TH_OPENING) { 4143 /* 4144 * we see an SA from 'dir' which is already in 4145 * SYN_SENT state, this means we have a 4146 * simultaneous open; SYN_SENT -> SYN_RECEIVED 4147 */ 4148 nstate = IPF_TCPS_SYN_RECEIVED; 4149 rval = 1; 4150 } 4151 break; 4152 4153 case IPF_TCPS_SYN_RECEIVED: /* 2 */ 4154 if ((tcpflags & (TH_SYN|TH_FIN|TH_ACK)) == TH_ACK) { 4155 /* 4156 * we see an A from 'dir' which was in 4157 * SYN_RECEIVED state so it must now be in 4158 * established state, SYN_RECEIVED -> 4159 * ESTABLISHED 4160 */ 4161 nstate = IPF_TCPS_ESTABLISHED; 4162 rval = 1; 4163 } else if ((tcpflags & ~(TH_ECN|TH_CWR)) == 4164 TH_OPENING) { 4165 /* 4166 * We see an SA from 'dir' which is already in 4167 * SYN_RECEIVED state. 4168 */ 4169 rval = 2; 4170 } else if (tcpflags & TH_FIN) { 4171 /* 4172 * we see an F from 'dir' which is in 4173 * SYN_RECEIVED state and wants to close its 4174 * side of the connection; SYN_RECEIVED -> 4175 * FIN_WAIT_1 4176 */ 4177 nstate = IPF_TCPS_FIN_WAIT_1; 4178 rval = 1; 4179 } 4180 break; 4181 4182 case IPF_TCPS_HALF_ESTAB: /* 3 */ 4183 if (tcpflags & TH_FIN) { 4184 nstate = IPF_TCPS_FIN_WAIT_1; 4185 rval = 1; 4186 } else if ((tcpflags & TH_ACKMASK) == TH_ACK) { 4187 /* 4188 * If we've picked up a connection in mid 4189 * flight, we could be looking at a follow on 4190 * packet from the same direction as the one 4191 * that created this state. Recognise it but 4192 * do not advance the entire connection's 4193 * state. 4194 */ 4195 switch (ostate) 4196 { 4197 case IPF_TCPS_LISTEN : 4198 case IPF_TCPS_SYN_SENT : 4199 case IPF_TCPS_SYN_RECEIVED : 4200 rval = 1; 4201 break; 4202 case IPF_TCPS_HALF_ESTAB : 4203 case IPF_TCPS_ESTABLISHED : 4204 nstate = IPF_TCPS_ESTABLISHED; 4205 rval = 1; 4206 break; 4207 default : 4208 break; 4209 } 4210 } 4211 break; 4212 4213 case IPF_TCPS_ESTABLISHED: /* 4 */ 4214 rval = 1; 4215 if (tcpflags & TH_FIN) { 4216 /* 4217 * 'dir' closed its side of the connection; 4218 * this gives us a half-closed connection; 4219 * ESTABLISHED -> FIN_WAIT_1 4220 */ 4221 if (ostate == IPF_TCPS_FIN_WAIT_1) { 4222 nstate = IPF_TCPS_CLOSING; 4223 } else { 4224 nstate = IPF_TCPS_FIN_WAIT_1; 4225 } 4226 } else if (tcpflags & TH_ACK) { 4227 /* 4228 * an ACK, should we exclude other flags here? 4229 */ 4230 if (ostate == IPF_TCPS_FIN_WAIT_1) { 4231 /* 4232 * We know the other side did an active 4233 * close, so we are ACKing the recvd 4234 * FIN packet (does the window matching 4235 * code guarantee this?) and go into 4236 * CLOSE_WAIT state; this gives us a 4237 * half-closed connection 4238 */ 4239 nstate = IPF_TCPS_CLOSE_WAIT; 4240 } else if (ostate < IPF_TCPS_CLOSE_WAIT) { 4241 /* 4242 * still a fully established 4243 * connection reset timeout 4244 */ 4245 nstate = IPF_TCPS_ESTABLISHED; 4246 } 4247 } 4248 break; 4249 4250 case IPF_TCPS_CLOSE_WAIT: /* 5 */ 4251 rval = 1; 4252 if (tcpflags & TH_FIN) { 4253 /* 4254 * application closed and 'dir' sent a FIN, 4255 * we're now going into LAST_ACK state 4256 */ 4257 nstate = IPF_TCPS_LAST_ACK; 4258 } else { 4259 /* 4260 * we remain in CLOSE_WAIT because the other 4261 * side has closed already and we did not 4262 * close our side yet; reset timeout 4263 */ 4264 nstate = IPF_TCPS_CLOSE_WAIT; 4265 } 4266 break; 4267 4268 case IPF_TCPS_FIN_WAIT_1: /* 6 */ 4269 rval = 1; 4270 if ((tcpflags & TH_ACK) && 4271 ostate > IPF_TCPS_CLOSE_WAIT) { 4272 /* 4273 * if the other side is not active anymore 4274 * it has sent us a FIN packet that we are 4275 * ack'ing now with an ACK; this means both 4276 * sides have now closed the connection and 4277 * we go into TIME_WAIT 4278 */ 4279 /* 4280 * XXX: how do we know we really are ACKing 4281 * the FIN packet here? does the window code 4282 * guarantee that? 4283 */ 4284 nstate = IPF_TCPS_LAST_ACK; 4285 } else { 4286 /* 4287 * we closed our side of the connection 4288 * already but the other side is still active 4289 * (ESTABLISHED/CLOSE_WAIT); continue with 4290 * this half-closed connection 4291 */ 4292 nstate = IPF_TCPS_FIN_WAIT_1; 4293 } 4294 break; 4295 4296 case IPF_TCPS_CLOSING: /* 7 */ 4297 if ((tcpflags & (TH_FIN|TH_ACK)) == TH_ACK) { 4298 nstate = IPF_TCPS_TIME_WAIT; 4299 } 4300 rval = 1; 4301 break; 4302 4303 case IPF_TCPS_LAST_ACK: /* 8 */ 4304 if (tcpflags & TH_ACK) { 4305 rval = 1; 4306 } 4307 /* 4308 * we cannot detect when we go out of LAST_ACK state 4309 * to CLOSED because that is based on the reception 4310 * of ACK packets; ipfilter can only detect that a 4311 * packet has been sent by a host 4312 */ 4313 break; 4314 4315 case IPF_TCPS_FIN_WAIT_2: /* 9 */ 4316 /* NOT USED */ 4317 break; 4318 4319 case IPF_TCPS_TIME_WAIT: /* 10 */ 4320 /* we're in 2MSL timeout now */ 4321 if (ostate == IPF_TCPS_LAST_ACK) { 4322 nstate = IPF_TCPS_CLOSED; 4323 rval = 1; 4324 } else { 4325 rval = 2; 4326 } 4327 break; 4328 4329 case IPF_TCPS_CLOSED: /* 11 */ 4330 rval = 2; 4331 break; 4332 4333 default : 4334#if !defined(_KERNEL) 4335 abort(); 4336#endif 4337 break; 4338 } 4339 } 4340 4341 /* 4342 * If rval == 2 then do not update the queue position, but treat the 4343 * packet as being ok. 4344 */ 4345 if (rval == 2) 4346 rval = 1; 4347 else if (rval == 1) { 4348 if (ok) 4349 tqe->tqe_state[dir] = nstate; 4350 if ((tqe->tqe_flags & TQE_RULEBASED) == 0) 4351 ipf_movequeue(softc->ipf_ticks, tqe, tqe->tqe_ifq, 4352 tqtab + nstate); 4353 } 4354 4355 return rval; 4356} 4357 4358 4359/* ------------------------------------------------------------------------ */ 4360/* Function: ipf_state_log */ 4361/* Returns: Nil */ 4362/* Parameters: softc(I) - pointer to soft context main structure */ 4363/* is(I) - pointer to state structure */ 4364/* type(I) - type of log entry to create */ 4365/* */ 4366/* Creates a state table log entry using the state structure and type info. */ 4367/* passed in. Log packet/byte counts, source/destination address and other */ 4368/* protocol specific information. */ 4369/* ------------------------------------------------------------------------ */ 4370void 4371ipf_state_log(softc, is, type) 4372 ipf_main_softc_t *softc; 4373 struct ipstate *is; 4374 u_int type; 4375{ 4376#ifdef IPFILTER_LOG 4377 struct ipslog ipsl; 4378 size_t sizes[1]; 4379 void *items[1]; 4380 int types[1]; 4381 4382 /* 4383 * Copy information out of the ipstate_t structure and into the 4384 * structure used for logging. 4385 */ 4386 ipsl.isl_type = type; 4387 ipsl.isl_pkts[0] = is->is_pkts[0] + is->is_icmppkts[0]; 4388 ipsl.isl_bytes[0] = is->is_bytes[0]; 4389 ipsl.isl_pkts[1] = is->is_pkts[1] + is->is_icmppkts[1]; 4390 ipsl.isl_bytes[1] = is->is_bytes[1]; 4391 ipsl.isl_pkts[2] = is->is_pkts[2] + is->is_icmppkts[2]; 4392 ipsl.isl_bytes[2] = is->is_bytes[2]; 4393 ipsl.isl_pkts[3] = is->is_pkts[3] + is->is_icmppkts[3]; 4394 ipsl.isl_bytes[3] = is->is_bytes[3]; 4395 ipsl.isl_src = is->is_src; 4396 ipsl.isl_dst = is->is_dst; 4397 ipsl.isl_p = is->is_p; 4398 ipsl.isl_v = is->is_v; 4399 ipsl.isl_flags = is->is_flags; 4400 ipsl.isl_tag = is->is_tag; 4401 ipsl.isl_rulen = is->is_rulen; 4402 (void) strncpy(ipsl.isl_group, is->is_group, FR_GROUPLEN); 4403 4404 if (ipsl.isl_p == IPPROTO_TCP || ipsl.isl_p == IPPROTO_UDP) { 4405 ipsl.isl_sport = is->is_sport; 4406 ipsl.isl_dport = is->is_dport; 4407 if (ipsl.isl_p == IPPROTO_TCP) { 4408 ipsl.isl_state[0] = is->is_state[0]; 4409 ipsl.isl_state[1] = is->is_state[1]; 4410 } 4411 } else if (ipsl.isl_p == IPPROTO_ICMP) { 4412 ipsl.isl_itype = is->is_icmp.ici_type; 4413 } else if (ipsl.isl_p == IPPROTO_ICMPV6) { 4414 ipsl.isl_itype = is->is_icmp.ici_type; 4415 } else { 4416 ipsl.isl_ps.isl_filler[0] = 0; 4417 ipsl.isl_ps.isl_filler[1] = 0; 4418 } 4419 4420 items[0] = &ipsl; 4421 sizes[0] = sizeof(ipsl); 4422 types[0] = 0; 4423 4424 (void) ipf_log_items(softc, IPL_LOGSTATE, NULL, items, sizes, types, 1); 4425#endif 4426} 4427 4428 4429#ifdef USE_INET6 4430/* ------------------------------------------------------------------------ */ 4431/* Function: ipf_checkicmp6matchingstate */ 4432/* Returns: ipstate_t* - NULL == no match found, */ 4433/* else pointer to matching state entry */ 4434/* Parameters: fin(I) - pointer to packet information */ 4435/* Locks: NULL == no locks, else Read Lock on ipf_state */ 4436/* */ 4437/* If we've got an ICMPv6 error message, using the information stored in */ 4438/* the ICMPv6 packet, look for a matching state table entry. */ 4439/* ------------------------------------------------------------------------ */ 4440static ipstate_t * 4441ipf_checkicmp6matchingstate(fin) 4442 fr_info_t *fin; 4443{ 4444 ipf_main_softc_t *softc = fin->fin_main_soft; 4445 ipf_state_softc_t *softs = softc->ipf_state_soft; 4446 struct icmp6_hdr *ic6, *oic; 4447 ipstate_t *is, **isp; 4448 u_short sport, dport; 4449 i6addr_t dst, src; 4450 u_short savelen; 4451 icmpinfo_t *ic; 4452 fr_info_t ofin; 4453 tcphdr_t *tcp; 4454 ip6_t *oip6; 4455 u_char pr; 4456 u_int hv; 4457 int type; 4458 4459 /* 4460 * Does it at least have the return (basic) IP header ? 4461 * Is it an actual recognised ICMP error type? 4462 * Only a basic IP header (no options) should be with 4463 * an ICMP error header. 4464 */ 4465 if ((fin->fin_v != 6) || (fin->fin_plen < ICMP6ERR_MINPKTLEN) || 4466 !(fin->fin_flx & FI_ICMPERR)) { 4467 SBUMPD(ipf_state_stats, iss_icmp_bad); 4468 return NULL; 4469 } 4470 4471 ic6 = fin->fin_dp; 4472 type = ic6->icmp6_type; 4473 4474 oip6 = (ip6_t *)((char *)ic6 + ICMPERR_ICMPHLEN); 4475 if (fin->fin_plen < sizeof(*oip6)) { 4476 SBUMPD(ipf_state_stats, iss_icmp_short); 4477 return NULL; 4478 } 4479 4480 bcopy((char *)fin, (char *)&ofin, sizeof(*fin)); 4481 ofin.fin_v = 6; 4482 ofin.fin_ifp = fin->fin_ifp; 4483 ofin.fin_out = !fin->fin_out; 4484 ofin.fin_m = NULL; /* if dereferenced, panic XXX */ 4485 ofin.fin_mp = NULL; /* if dereferenced, panic XXX */ 4486 4487 /* 4488 * We make a fin entry to be able to feed it to 4489 * matchsrcdst. Note that not all fields are necessary 4490 * but this is the cleanest way. Note further we fill 4491 * in fin_mp such that if someone uses it we'll get 4492 * a kernel panic. ipf_matchsrcdst does not use this. 4493 * 4494 * watch out here, as ip is in host order and oip6 in network 4495 * order. Any change we make must be undone afterwards. 4496 */ 4497 savelen = oip6->ip6_plen; 4498 oip6->ip6_plen = htons(fin->fin_dlen - ICMPERR_ICMPHLEN); 4499 ofin.fin_flx = FI_NOCKSUM; 4500 ofin.fin_ip = (ip_t *)oip6; 4501 (void) ipf_makefrip(sizeof(*oip6), (ip_t *)oip6, &ofin); 4502 ofin.fin_flx &= ~(FI_BAD|FI_SHORT); 4503 oip6->ip6_plen = savelen; 4504 pr = ofin.fin_p; 4505 4506 /* 4507 * an ICMP error can never generate an ICMP error in response. 4508 */ 4509 if (ofin.fin_flx & FI_ICMPERR) { 4510 DT1(iss_icmp6_icmperr, fr_info_t *, &ofin); 4511 SBUMP(ipf_state_stats.iss_icmp6_icmperr); 4512 return NULL; 4513 } 4514 4515 if (oip6->ip6_nxt == IPPROTO_ICMPV6) { 4516 oic = ofin.fin_dp; 4517 /* 4518 * an ICMP error can only be generated as a result of an 4519 * ICMP query, not as the response on an ICMP error 4520 * 4521 * XXX theoretically ICMP_ECHOREP and the other reply's are 4522 * ICMP query's as well, but adding them here seems strange XXX 4523 */ 4524 if (!(oic->icmp6_type & ICMP6_INFOMSG_MASK)) { 4525 DT1(iss_icmp6_notinfo, fr_info_t *, &ofin); 4526 SBUMP(ipf_state_stats.iss_icmp6_notinfo); 4527 return NULL; 4528 } 4529 4530 /* 4531 * perform a lookup of the ICMP packet in the state table 4532 */ 4533 hv = (pr = oip6->ip6_nxt); 4534 src.in6 = oip6->ip6_src; 4535 hv += src.in4.s_addr; 4536 dst.in6 = oip6->ip6_dst; 4537 hv += dst.in4.s_addr; 4538 hv += oic->icmp6_id; 4539 hv += oic->icmp6_seq; 4540 hv = DOUBLE_HASH(hv); 4541 4542 READ_ENTER(&softc->ipf_state); 4543 for (isp = &softs->ipf_state_table[hv]; 4544 ((is = *isp) != NULL); ) { 4545 ic = &is->is_icmp; 4546 isp = &is->is_hnext; 4547 if ((is->is_p == pr) && 4548 !(is->is_pass & FR_NOICMPERR) && 4549 (oic->icmp6_id == ic->ici_id) && 4550 (oic->icmp6_seq == ic->ici_seq) && 4551 (is = ipf_matchsrcdst(&ofin, is, &src, 4552 &dst, NULL, FI_ICMPCMP))) { 4553 /* 4554 * in the state table ICMP query's are stored 4555 * with the type of the corresponding ICMP 4556 * response. Correct here 4557 */ 4558 if (((ic->ici_type == ICMP6_ECHO_REPLY) && 4559 (oic->icmp6_type == ICMP6_ECHO_REQUEST)) || 4560 (ic->ici_type - 1 == oic->icmp6_type )) { 4561 if (!ipf_allowstateicmp(fin, is, &src)) 4562 return is; 4563 } 4564 } 4565 } 4566 RWLOCK_EXIT(&softc->ipf_state); 4567 SBUMPD(ipf_state_stats, iss_icmp6_miss); 4568 return NULL; 4569 } 4570 4571 hv = (pr = oip6->ip6_nxt); 4572 src.in6 = oip6->ip6_src; 4573 hv += src.i6[0]; 4574 hv += src.i6[1]; 4575 hv += src.i6[2]; 4576 hv += src.i6[3]; 4577 dst.in6 = oip6->ip6_dst; 4578 hv += dst.i6[0]; 4579 hv += dst.i6[1]; 4580 hv += dst.i6[2]; 4581 hv += dst.i6[3]; 4582 4583 tcp = NULL; 4584 4585 switch (oip6->ip6_nxt) 4586 { 4587 case IPPROTO_TCP : 4588 case IPPROTO_UDP : 4589 tcp = (tcphdr_t *)(oip6 + 1); 4590 dport = tcp->th_dport; 4591 sport = tcp->th_sport; 4592 hv += dport; 4593 hv += sport; 4594 break; 4595 4596 case IPPROTO_ICMPV6 : 4597 oic = (struct icmp6_hdr *)(oip6 + 1); 4598 hv += oic->icmp6_id; 4599 hv += oic->icmp6_seq; 4600 break; 4601 4602 default : 4603 break; 4604 } 4605 4606 hv = DOUBLE_HASH(hv); 4607 4608 READ_ENTER(&softc->ipf_state); 4609 for (isp = &softs->ipf_state_table[hv]; ((is = *isp) != NULL); ) { 4610 isp = &is->is_hnext; 4611 /* 4612 * Only allow this icmp though if the 4613 * encapsulated packet was allowed through the 4614 * other way around. Note that the minimal amount 4615 * of info present does not allow for checking against 4616 * tcp internals such as seq and ack numbers. 4617 */ 4618 if ((is->is_p != pr) || (is->is_v != 6) || 4619 (is->is_pass & FR_NOICMPERR)) 4620 continue; 4621 is = ipf_matchsrcdst(&ofin, is, &src, &dst, tcp, FI_ICMPCMP); 4622 if ((is != NULL) && (ipf_allowstateicmp(fin, is, &src) == 0)) 4623 return is; 4624 } 4625 RWLOCK_EXIT(&softc->ipf_state); 4626 SBUMPD(ipf_state_stats, iss_icmp_miss); 4627 return NULL; 4628} 4629#endif 4630 4631 4632/* ------------------------------------------------------------------------ */ 4633/* Function: ipf_sttab_init */ 4634/* Returns: Nil */ 4635/* Parameters: softc(I) - pointer to soft context main structure */ 4636/* tqp(I) - pointer to an array of timeout queues for TCP */ 4637/* */ 4638/* Initialise the array of timeout queues for TCP. */ 4639/* ------------------------------------------------------------------------ */ 4640void 4641ipf_sttab_init(softc, tqp) 4642 ipf_main_softc_t *softc; 4643 ipftq_t *tqp; 4644{ 4645 int i; 4646 4647 for (i = IPF_TCP_NSTATES - 1; i >= 0; i--) { 4648 IPFTQ_INIT(&tqp[i], 0, "ipftq tcp tab"); 4649 tqp[i].ifq_next = tqp + i + 1; 4650 } 4651 tqp[IPF_TCP_NSTATES - 1].ifq_next = NULL; 4652 tqp[IPF_TCPS_CLOSED].ifq_ttl = softc->ipf_tcpclosed; 4653 tqp[IPF_TCPS_LISTEN].ifq_ttl = softc->ipf_tcptimeout; 4654 tqp[IPF_TCPS_SYN_SENT].ifq_ttl = softc->ipf_tcpsynsent; 4655 tqp[IPF_TCPS_SYN_RECEIVED].ifq_ttl = softc->ipf_tcpsynrecv; 4656 tqp[IPF_TCPS_ESTABLISHED].ifq_ttl = softc->ipf_tcpidletimeout; 4657 tqp[IPF_TCPS_CLOSE_WAIT].ifq_ttl = softc->ipf_tcphalfclosed; 4658 tqp[IPF_TCPS_FIN_WAIT_1].ifq_ttl = softc->ipf_tcphalfclosed; 4659 tqp[IPF_TCPS_CLOSING].ifq_ttl = softc->ipf_tcptimeout; 4660 tqp[IPF_TCPS_LAST_ACK].ifq_ttl = softc->ipf_tcplastack; 4661 tqp[IPF_TCPS_FIN_WAIT_2].ifq_ttl = softc->ipf_tcpclosewait; 4662 tqp[IPF_TCPS_TIME_WAIT].ifq_ttl = softc->ipf_tcptimewait; 4663 tqp[IPF_TCPS_HALF_ESTAB].ifq_ttl = softc->ipf_tcptimeout; 4664} 4665 4666 4667/* ------------------------------------------------------------------------ */ 4668/* Function: ipf_sttab_destroy */ 4669/* Returns: Nil */ 4670/* Parameters: tqp(I) - pointer to an array of timeout queues for TCP */ 4671/* */ 4672/* Do whatever is necessary to "destroy" each of the entries in the array */ 4673/* of timeout queues for TCP. */ 4674/* ------------------------------------------------------------------------ */ 4675void 4676ipf_sttab_destroy(tqp) 4677 ipftq_t *tqp; 4678{ 4679 int i; 4680 4681 for (i = IPF_TCP_NSTATES - 1; i >= 0; i--) 4682 MUTEX_DESTROY(&tqp[i].ifq_lock); 4683} 4684 4685 4686/* ------------------------------------------------------------------------ */ 4687/* Function: ipf_state_deref */ 4688/* Returns: Nil */ 4689/* Parameters: softc(I) - pointer to soft context main structure */ 4690/* isp(I) - pointer to pointer to state table entry */ 4691/* */ 4692/* Decrement the reference counter for this state table entry and free it */ 4693/* if there are no more things using it. */ 4694/* */ 4695/* This function is only called when cleaning up after increasing is_ref by */ 4696/* one earlier in the 'code path' so if is_ref is 1 when entering, we do */ 4697/* have an orphan, otherwise not. However there is a possible race between */ 4698/* the entry being deleted via flushing with an ioctl call (that calls the */ 4699/* delete function directly) and the tail end of packet processing so we */ 4700/* need to grab is_lock before doing the check to synchronise the two code */ 4701/* paths. */ 4702/* */ 4703/* When operating in userland (ipftest), we have no timers to clear a state */ 4704/* entry. Therefore, we make a few simple tests before deleting an entry */ 4705/* outright. We compare states on each side looking for a combination of */ 4706/* TIME_WAIT (should really be FIN_WAIT_2?) and LAST_ACK. Then we factor */ 4707/* in packet direction with the interface list to make sure we don't */ 4708/* prematurely delete an entry on a final inbound packet that's we're also */ 4709/* supposed to route elsewhere. */ 4710/* */ 4711/* Internal parameters: */ 4712/* state[0] = state of source (host that initiated connection) */ 4713/* state[1] = state of dest (host that accepted the connection) */ 4714/* */ 4715/* dir == 0 : a packet from source to dest */ 4716/* dir == 1 : a packet from dest to source */ 4717/* ------------------------------------------------------------------------ */ 4718void 4719ipf_state_deref(softc, isp) 4720 ipf_main_softc_t *softc; 4721 ipstate_t **isp; 4722{ 4723 ipstate_t *is = *isp; 4724 4725 is = *isp; 4726 *isp = NULL; 4727 4728 MUTEX_ENTER(&is->is_lock); 4729 if (is->is_ref > 1) { 4730 is->is_ref--; 4731 MUTEX_EXIT(&is->is_lock); 4732#ifndef _KERNEL 4733 if ((is->is_sti.tqe_state[0] > IPF_TCPS_ESTABLISHED) || 4734 (is->is_sti.tqe_state[1] > IPF_TCPS_ESTABLISHED)) { 4735 ipf_state_del(softc, is, ISL_EXPIRE); 4736 } 4737#endif 4738 return; 4739 } 4740 MUTEX_EXIT(&is->is_lock); 4741 4742 WRITE_ENTER(&softc->ipf_state); 4743 ipf_state_del(softc, is, ISL_ORPHAN); 4744 RWLOCK_EXIT(&softc->ipf_state); 4745} 4746 4747 4748/* ------------------------------------------------------------------------ */ 4749/* Function: ipf_state_setqueue */ 4750/* Returns: Nil */ 4751/* Parameters: softc(I) - pointer to soft context main structure */ 4752/* is(I) - pointer to state structure */ 4753/* rev(I) - forward(0) or reverse(1) direction */ 4754/* Locks: ipf_state (read or write) */ 4755/* */ 4756/* Put the state entry on its default queue entry, using rev as a helped in */ 4757/* determining which queue it should be placed on. */ 4758/* ------------------------------------------------------------------------ */ 4759void 4760ipf_state_setqueue(softc, is, rev) 4761 ipf_main_softc_t *softc; 4762 ipstate_t *is; 4763 int rev; 4764{ 4765 ipf_state_softc_t *softs = softc->ipf_state_soft; 4766 ipftq_t *oifq, *nifq; 4767 4768 if ((is->is_sti.tqe_flags & TQE_RULEBASED) != 0) 4769 nifq = is->is_tqehead[rev]; 4770 else 4771 nifq = NULL; 4772 4773 if (nifq == NULL) { 4774 switch (is->is_p) 4775 { 4776#ifdef USE_INET6 4777 case IPPROTO_ICMPV6 : 4778 if (rev == 1) 4779 nifq = &softs->ipf_state_icmpacktq; 4780 else 4781 nifq = &softs->ipf_state_icmptq; 4782 break; 4783#endif 4784 case IPPROTO_ICMP : 4785 if (rev == 1) 4786 nifq = &softs->ipf_state_icmpacktq; 4787 else 4788 nifq = &softs->ipf_state_icmptq; 4789 break; 4790 case IPPROTO_TCP : 4791 nifq = softs->ipf_state_tcptq + is->is_state[rev]; 4792 break; 4793 4794 case IPPROTO_UDP : 4795 if (rev == 1) 4796 nifq = &softs->ipf_state_udpacktq; 4797 else 4798 nifq = &softs->ipf_state_udptq; 4799 break; 4800 4801 default : 4802 nifq = &softs->ipf_state_iptq; 4803 break; 4804 } 4805 } 4806 4807 oifq = is->is_sti.tqe_ifq; 4808 /* 4809 * If it's currently on a timeout queue, move it from one queue to 4810 * another, else put it on the end of the newly determined queue. 4811 */ 4812 if (oifq != NULL) 4813 ipf_movequeue(softc->ipf_ticks, &is->is_sti, oifq, nifq); 4814 else 4815 ipf_queueappend(softc->ipf_ticks, &is->is_sti, nifq, is); 4816 return; 4817} 4818 4819 4820/* ------------------------------------------------------------------------ */ 4821/* Function: ipf_state_iter */ 4822/* Returns: int - 0 == success, else error */ 4823/* Parameters: softc(I) - pointer to main soft context */ 4824/* token(I) - pointer to ipftoken structure */ 4825/* itp(I) - pointer to ipfgeniter structure */ 4826/* obj(I) - pointer to data description structure */ 4827/* */ 4828/* This function handles the SIOCGENITER ioctl for the state tables and */ 4829/* walks through the list of entries in the state table list (softs->ipf_state_list.) */ 4830/* ------------------------------------------------------------------------ */ 4831static int 4832ipf_state_iter(softc, token, itp, obj) 4833 ipf_main_softc_t *softc; 4834 ipftoken_t *token; 4835 ipfgeniter_t *itp; 4836 ipfobj_t *obj; 4837{ 4838 ipf_state_softc_t *softs = softc->ipf_state_soft; 4839 ipstate_t *is, *next, zero; 4840 int error; 4841 4842 if (itp->igi_data == NULL) { 4843 IPFERROR(100026); 4844 return EFAULT; 4845 } 4846 4847 if (itp->igi_nitems < 1) { 4848 IPFERROR(100027); 4849 return ENOSPC; 4850 } 4851 4852 if (itp->igi_type != IPFGENITER_STATE) { 4853 IPFERROR(100028); 4854 return EINVAL; 4855 } 4856 4857 is = token->ipt_data; 4858 if (is == (void *)-1) { 4859 IPFERROR(100029); 4860 return ESRCH; 4861 } 4862 4863 error = 0; 4864 obj->ipfo_type = IPFOBJ_IPSTATE; 4865 obj->ipfo_size = sizeof(ipstate_t); 4866 4867 READ_ENTER(&softc->ipf_state); 4868 4869 is = token->ipt_data; 4870 if (is == NULL) { 4871 next = softs->ipf_state_list; 4872 } else { 4873 next = is->is_next; 4874 } 4875 4876 /* 4877 * If we find a state entry to use, bump its reference count so that 4878 * it can be used for is_next when we come back. 4879 */ 4880 if (next != NULL) { 4881 MUTEX_ENTER(&next->is_lock); 4882 next->is_ref++; 4883 MUTEX_EXIT(&next->is_lock); 4884 token->ipt_data = next; 4885 } else { 4886 bzero(&zero, sizeof(zero)); 4887 next = &zero; 4888 token->ipt_data = NULL; 4889 } 4890 if (next->is_next == NULL) 4891 ipf_token_mark_complete(token); 4892 4893 RWLOCK_EXIT(&softc->ipf_state); 4894 4895 obj->ipfo_ptr = itp->igi_data; 4896 error = ipf_outobjk(softc, obj, next); 4897 if (is != NULL) 4898 ipf_state_deref(softc, &is); 4899 4900 return error; 4901} 4902 4903 4904/* ------------------------------------------------------------------------ */ 4905/* Function: ipf_state_gettable */ 4906/* Returns: int - 0 = success, else error */ 4907/* Parameters: softc(I) - pointer to main soft context */ 4908/* softs(I) - pointer to state context structure */ 4909/* data(I) - pointer to ioctl data */ 4910/* */ 4911/* This function handles ioctl requests for tables of state information. */ 4912/* At present the only table it deals with is the hash bucket statistics. */ 4913/* ------------------------------------------------------------------------ */ 4914static int 4915ipf_state_gettable(softc, softs, data) 4916 ipf_main_softc_t *softc; 4917 ipf_state_softc_t *softs; 4918 char *data; 4919{ 4920 ipftable_t table; 4921 int error; 4922 4923 error = ipf_inobj(softc, data, NULL, &table, IPFOBJ_GTABLE); 4924 if (error != 0) 4925 return error; 4926 4927 if (table.ita_type != IPFTABLE_BUCKETS) { 4928 IPFERROR(100031); 4929 return EINVAL; 4930 } 4931 4932 error = COPYOUT(softs->ipf_state_stats.iss_bucketlen, table.ita_table, 4933 softs->ipf_state_size * sizeof(u_int)); 4934 if (error != 0) { 4935 IPFERROR(100032); 4936 error = EFAULT; 4937 } 4938 return error; 4939} 4940 4941 4942/* ------------------------------------------------------------------------ */ 4943/* Function: ipf_state_setpending */ 4944/* Returns: Nil */ 4945/* Parameters: softc(I) - pointer to main soft context */ 4946/* is(I) - pointer to state structure */ 4947/* Locks: ipf_state (read or write) */ 4948/* */ 4949/* Put the state entry on to the pending queue - this queue has a very */ 4950/* short lifetime where items are put that can't be deleted straight away */ 4951/* because of locking issues but we want to delete them ASAP, anyway. */ 4952/* ------------------------------------------------------------------------ */ 4953void 4954ipf_state_setpending(softc, is) 4955 ipf_main_softc_t *softc; 4956 ipstate_t *is; 4957{ 4958 ipf_state_softc_t *softs = softc->ipf_state_soft; 4959 ipftq_t *oifq; 4960 4961 oifq = is->is_sti.tqe_ifq; 4962 if (oifq != NULL) 4963 ipf_movequeue(softc->ipf_ticks, &is->is_sti, oifq, 4964 &softs->ipf_state_pending); 4965 else 4966 ipf_queueappend(softc->ipf_ticks, &is->is_sti, 4967 &softs->ipf_state_pending, is); 4968 4969 MUTEX_ENTER(&is->is_lock); 4970 if (is->is_me != NULL) { 4971 *is->is_me = NULL; 4972 is->is_me = NULL; 4973 is->is_ref--; 4974 } 4975 MUTEX_EXIT(&is->is_lock); 4976} 4977 4978 4979/* ------------------------------------------------------------------------ */ 4980/* Function: ipf_state_matchflush */ 4981/* Returns: Nil */ 4982/* Parameters: softc(I) - pointer to main soft context */ 4983/* data(I) - pointer to state structure */ 4984/* Locks: ipf_state (read or write) */ 4985/* */ 4986/* Flush all entries from the list of state entries that match the */ 4987/* properties in the array loaded. */ 4988/* ------------------------------------------------------------------------ */ 4989int 4990ipf_state_matchflush(softc, data) 4991 ipf_main_softc_t *softc; 4992 caddr_t data; 4993{ 4994 ipf_state_softc_t *softs = softc->ipf_state_soft; 4995 int *array, flushed, error; 4996 ipstate_t *state, *statenext; 4997 ipfobj_t obj; 4998 4999 error = ipf_matcharray_load(softc, data, &obj, &array); 5000 if (error != 0) 5001 return error; 5002 5003 flushed = 0; 5004 5005 for (state = softs->ipf_state_list; state != NULL; state = statenext) { 5006 statenext = state->is_next; 5007 if (ipf_state_matcharray(state, array, softc->ipf_ticks) == 0) { 5008 ipf_state_del(softc, state, ISL_FLUSH); 5009 flushed++; 5010 } 5011 } 5012 5013 obj.ipfo_retval = flushed; 5014 error = BCOPYOUT(&obj, data, sizeof(obj)); 5015 5016 KFREES(array, array[0] * sizeof(*array)); 5017 5018 return error; 5019} 5020 5021 5022/* ------------------------------------------------------------------------ */ 5023/* Function: ipf_state_matcharray */ 5024/* Returns: int - 0 = no match, 1 = match */ 5025/* Parameters: state(I) - pointer to state structure */ 5026/* array(I) - pointer to ipf matching expression */ 5027/* ticks(I) - current value of ipfilter tick timer */ 5028/* Locks: ipf_state (read or write) */ 5029/* */ 5030/* Compare a state entry with the match array passed in and return a value */ 5031/* to indicate whether or not the matching was successful. */ 5032/* ------------------------------------------------------------------------ */ 5033static int 5034ipf_state_matcharray(state, array, ticks) 5035 ipstate_t *state; 5036 int *array; 5037 u_long ticks; 5038{ 5039 int i, n, *x, rv, p; 5040 ipfexp_t *e; 5041 5042 rv = 0; 5043 n = array[0]; 5044 x = array + 1; 5045 5046 for (; n > 0; x += 3 + x[3], rv = 0) { 5047 e = (ipfexp_t *)x; 5048 n -= e->ipfe_size; 5049 if (x[0] == IPF_EXP_END) 5050 break; 5051 5052 /* 5053 * If we need to match the protocol and that doesn't match, 5054 * don't even both with the instruction array. 5055 */ 5056 p = e->ipfe_cmd >> 16; 5057 if ((p != 0) && (p != state->is_p)) 5058 break; 5059 5060 switch (e->ipfe_cmd) 5061 { 5062 case IPF_EXP_IP_PR : 5063 for (i = 0; !rv && i < e->ipfe_narg; i++) { 5064 rv |= (state->is_p == e->ipfe_arg0[i]); 5065 } 5066 break; 5067 5068 case IPF_EXP_IP_SRCADDR : 5069 if (state->is_v != 4) 5070 break; 5071 for (i = 0; !rv && i < e->ipfe_narg; i++) { 5072 rv |= ((state->is_saddr & 5073 e->ipfe_arg0[i * 2 + 1]) == 5074 e->ipfe_arg0[i * 2]); 5075 } 5076 break; 5077 5078 case IPF_EXP_IP_DSTADDR : 5079 if (state->is_v != 4) 5080 break; 5081 for (i = 0; !rv && i < e->ipfe_narg; i++) { 5082 rv |= ((state->is_daddr & 5083 e->ipfe_arg0[i * 2 + 1]) == 5084 e->ipfe_arg0[i * 2]); 5085 } 5086 break; 5087 5088 case IPF_EXP_IP_ADDR : 5089 if (state->is_v != 4) 5090 break; 5091 for (i = 0; !rv && i < e->ipfe_narg; i++) { 5092 rv |= ((state->is_saddr & 5093 e->ipfe_arg0[i * 2 + 1]) == 5094 e->ipfe_arg0[i * 2]) || 5095 ((state->is_daddr & 5096 e->ipfe_arg0[i * 2 + 1]) == 5097 e->ipfe_arg0[i * 2]); 5098 } 5099 break; 5100 5101#ifdef USE_INET6 5102 case IPF_EXP_IP6_SRCADDR : 5103 if (state->is_v != 6) 5104 break; 5105 for (i = 0; !rv && i < x[3]; i++) { 5106 rv |= IP6_MASKEQ(&state->is_src.in6, 5107 &e->ipfe_arg0[i * 8 + 4], 5108 &e->ipfe_arg0[i * 8]); 5109 } 5110 break; 5111 5112 case IPF_EXP_IP6_DSTADDR : 5113 if (state->is_v != 6) 5114 break; 5115 for (i = 0; !rv && i < x[3]; i++) { 5116 rv |= IP6_MASKEQ(&state->is_dst.in6, 5117 &e->ipfe_arg0[i * 8 + 4], 5118 &e->ipfe_arg0[i * 8]); 5119 } 5120 break; 5121 5122 case IPF_EXP_IP6_ADDR : 5123 if (state->is_v != 6) 5124 break; 5125 for (i = 0; !rv && i < x[3]; i++) { 5126 rv |= IP6_MASKEQ(&state->is_src.in6, 5127 &e->ipfe_arg0[i * 8 + 4], 5128 &e->ipfe_arg0[i * 8]) || 5129 IP6_MASKEQ(&state->is_dst.in6, 5130 &e->ipfe_arg0[i * 8 + 4], 5131 &e->ipfe_arg0[i * 8]); 5132 } 5133 break; 5134#endif 5135 5136 case IPF_EXP_UDP_PORT : 5137 case IPF_EXP_TCP_PORT : 5138 for (i = 0; !rv && i < e->ipfe_narg; i++) { 5139 rv |= (state->is_sport == e->ipfe_arg0[i]) || 5140 (state->is_dport == e->ipfe_arg0[i]); 5141 } 5142 break; 5143 5144 case IPF_EXP_UDP_SPORT : 5145 case IPF_EXP_TCP_SPORT : 5146 for (i = 0; !rv && i < e->ipfe_narg; i++) { 5147 rv |= (state->is_sport == e->ipfe_arg0[i]); 5148 } 5149 break; 5150 5151 case IPF_EXP_UDP_DPORT : 5152 case IPF_EXP_TCP_DPORT : 5153 for (i = 0; !rv && i < e->ipfe_narg; i++) { 5154 rv |= (state->is_dport == e->ipfe_arg0[i]); 5155 } 5156 break; 5157 5158 case IPF_EXP_TCP_STATE : 5159 for (i = 0; !rv && i < e->ipfe_narg; i++) { 5160 rv |= (state->is_state[0] == e->ipfe_arg0[i]) || 5161 (state->is_state[1] == e->ipfe_arg0[i]); 5162 } 5163 break; 5164 5165 case IPF_EXP_IDLE_GT : 5166 rv |= (ticks - state->is_touched > e->ipfe_arg0[0]); 5167 break; 5168 } 5169 5170 /* 5171 * Factor in doing a negative match. 5172 */ 5173 rv ^= e->ipfe_not; 5174 5175 if (rv == 0) 5176 break; 5177 } 5178 5179 return rv; 5180} 5181 5182 5183/* ------------------------------------------------------------------------ */ 5184/* Function: ipf_state_settimeout */ 5185/* Returns: int 0 = success, else failure */ 5186/* Parameters: softc(I) - pointer to main soft context */ 5187/* t(I) - pointer to tuneable being changed */ 5188/* p(I) - pointer to the new value */ 5189/* */ 5190/* Sets a timeout value for one of the many timeout queues. We find the */ 5191/* correct queue using a somewhat manual process of comparing the timeout */ 5192/* names for each specific value available and calling ipf_apply_timeout on */ 5193/* that queue so that all of the items on it are updated accordingly. */ 5194/* ------------------------------------------------------------------------ */ 5195int 5196ipf_state_settimeout(softc, t, p) 5197 struct ipf_main_softc_s *softc; 5198 ipftuneable_t *t; 5199 ipftuneval_t *p; 5200{ 5201 ipf_state_softc_t *softs = softc->ipf_state_soft; 5202 5203 /* 5204 * In case there is nothing to do... 5205 */ 5206 if (*t->ipft_pint == p->ipftu_int) 5207 return 0; 5208 5209 if (!strncmp(t->ipft_name, "tcp_", 4)) 5210 return ipf_settimeout_tcp(t, p, softs->ipf_state_tcptq); 5211 5212 if (!strcmp(t->ipft_name, "udp_timeout")) { 5213 ipf_apply_timeout(&softs->ipf_state_udptq, p->ipftu_int); 5214 } else if (!strcmp(t->ipft_name, "udp_ack_timeout")) { 5215 ipf_apply_timeout(&softs->ipf_state_udpacktq, p->ipftu_int); 5216 } else if (!strcmp(t->ipft_name, "icmp_timeout")) { 5217 ipf_apply_timeout(&softs->ipf_state_icmptq, p->ipftu_int); 5218 } else if (!strcmp(t->ipft_name, "icmp_ack_timeout")) { 5219 ipf_apply_timeout(&softs->ipf_state_icmpacktq, p->ipftu_int); 5220 } else if (!strcmp(t->ipft_name, "ip_timeout")) { 5221 ipf_apply_timeout(&softs->ipf_state_iptq, p->ipftu_int); 5222 } else { 5223 IPFERROR(100034); 5224 return ESRCH; 5225 } 5226 5227 /* 5228 * Update the tuneable being set. 5229 */ 5230 *t->ipft_pint = p->ipftu_int; 5231 5232 return 0; 5233} 5234 5235 5236/* ------------------------------------------------------------------------ */ 5237/* Function: ipf_state_rehash */ 5238/* Returns: int 0 = success, else failure */ 5239/* Parameters: softc(I) - pointer to main soft context */ 5240/* t(I) - pointer to tuneable being changed */ 5241/* p(I) - pointer to the new value */ 5242/* */ 5243/* To change the size of the state hash table at runtime, a new table has */ 5244/* to be allocated and then all of the existing entries put in it, bumping */ 5245/* up the bucketlength for it as we go along. */ 5246/* ------------------------------------------------------------------------ */ 5247int 5248ipf_state_rehash(softc, t, p) 5249 ipf_main_softc_t *softc; 5250 ipftuneable_t *t; 5251 ipftuneval_t *p; 5252{ 5253 ipf_state_softc_t *softs = softc->ipf_state_soft; 5254 ipstate_t **newtab, *is; 5255 u_int *bucketlens; 5256 u_int maxbucket; 5257 u_int newsize; 5258 u_int hv; 5259 int i; 5260 5261 newsize = p->ipftu_int; 5262 /* 5263 * In case there is nothing to do... 5264 */ 5265 if (newsize == softs->ipf_state_size) 5266 return 0; 5267 5268 KMALLOCS(newtab, ipstate_t **, newsize * sizeof(ipstate_t *)); 5269 if (newtab == NULL) { 5270 IPFERROR(100035); 5271 return ENOMEM; 5272 } 5273 5274 KMALLOCS(bucketlens, u_int *, newsize * sizeof(u_int)); 5275 if (bucketlens == NULL) { 5276 KFREES(newtab, newsize * sizeof(*softs->ipf_state_table)); 5277 IPFERROR(100036); 5278 return ENOMEM; 5279 } 5280 5281 for (maxbucket = 0, i = newsize; i > 0; i >>= 1) 5282 maxbucket++; 5283 maxbucket *= 2; 5284 5285 bzero((char *)newtab, newsize * sizeof(ipstate_t *)); 5286 bzero((char *)bucketlens, newsize * sizeof(u_int)); 5287 5288 WRITE_ENTER(&softc->ipf_state); 5289 5290 if (softs->ipf_state_table != NULL) { 5291 KFREES(softs->ipf_state_table, 5292 softs->ipf_state_size * sizeof(*softs->ipf_state_table)); 5293 } 5294 softs->ipf_state_table = newtab; 5295 5296 if (softs->ipf_state_stats.iss_bucketlen != NULL) { 5297 KFREES(softs->ipf_state_stats.iss_bucketlen, 5298 softs->ipf_state_size * sizeof(u_int)); 5299 } 5300 softs->ipf_state_stats.iss_bucketlen = bucketlens; 5301 softs->ipf_state_maxbucket = maxbucket; 5302 softs->ipf_state_size = newsize; 5303 5304 /* 5305 * Walk through the entire list of state table entries and put them 5306 * in the new state table, somewhere. Because we have a new table, 5307 * we need to restart the counter of how many chains are in use. 5308 */ 5309 softs->ipf_state_stats.iss_inuse = 0; 5310 for (is = softs->ipf_state_list; is != NULL; is = is->is_next) { 5311 is->is_hnext = NULL; 5312 is->is_phnext = NULL; 5313 hv = is->is_hv % softs->ipf_state_size; 5314 5315 if (softs->ipf_state_table[hv] != NULL) 5316 softs->ipf_state_table[hv]->is_phnext = &is->is_hnext; 5317 else 5318 softs->ipf_state_stats.iss_inuse++; 5319 is->is_phnext = softs->ipf_state_table + hv; 5320 is->is_hnext = softs->ipf_state_table[hv]; 5321 softs->ipf_state_table[hv] = is; 5322 softs->ipf_state_stats.iss_bucketlen[hv]++; 5323 } 5324 RWLOCK_EXIT(&softc->ipf_state); 5325 5326 return 0; 5327} 5328 5329 5330/* ------------------------------------------------------------------------ */ 5331/* Function: ipf_state_add_tq */ 5332/* Returns: ipftq_t * - NULL = failure, else pointer to new timeout */ 5333/* queue */ 5334/* Parameters: softc(I) - pointer to main soft context */ 5335/* ttl(I) - pointer to the ttl for the new queue */ 5336/* */ 5337/* Request a pointer to a timeout queue that has a ttl as given by the */ 5338/* value being passed in. The timeout queue is added tot the list of those */ 5339/* used internally for stateful filtering. */ 5340/* ------------------------------------------------------------------------ */ 5341ipftq_t * 5342ipf_state_add_tq(softc, ttl) 5343 ipf_main_softc_t *softc; 5344 int ttl; 5345{ 5346 ipf_state_softc_t *softs = softc->ipf_state_soft; 5347 5348 return ipf_addtimeoutqueue(softc, &softs->ipf_state_usertq, ttl); 5349} 5350 5351 5352#ifndef _KERNEL 5353/* 5354 * Display the built up state table rules and mapping entries. 5355 */ 5356void 5357ipf_state_dump(softc, arg) 5358 ipf_main_softc_t *softc; 5359 void *arg; 5360{ 5361 ipf_state_softc_t *softs = arg; 5362 ipstate_t *ips; 5363 5364 printf("List of active state sessions:\n"); 5365 for (ips = softs->ipf_state_list; ips != NULL; ) 5366 ips = printstate(ips, opts & (OPT_DEBUG|OPT_VERBOSE), 5367 softc->ipf_ticks); 5368} 5369#endif 5370