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