1 /* 2 * Copyright (C) 1995-2003 by Darren Reed. 3 * 4 * See the IPFILTER.LICENCE file for details on licencing. 5 * 6 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 7 * Use is subject to license terms. 8 */ 9 10 #pragma ident "%Z%%M% %I% %E% SMI" 11 12 #if defined(KERNEL) || defined(_KERNEL) 13 # undef KERNEL 14 # undef _KERNEL 15 # define KERNEL 1 16 # define _KERNEL 1 17 #endif 18 #include <sys/errno.h> 19 #include <sys/types.h> 20 #include <sys/param.h> 21 #include <sys/file.h> 22 #if defined(__NetBSD__) && (NetBSD >= 199905) && !defined(IPFILTER_LKM) && \ 23 defined(_KERNEL) 24 # include "opt_ipfilter_log.h" 25 #endif 26 #if defined(_KERNEL) && defined(__FreeBSD_version) && \ 27 (__FreeBSD_version >= 400000) && !defined(KLD_MODULE) 28 #include "opt_inet6.h" 29 #endif 30 #if !defined(_KERNEL) && !defined(__KERNEL__) 31 # include <stdio.h> 32 # include <stdlib.h> 33 # include <string.h> 34 # define _KERNEL 35 # ifdef __OpenBSD__ 36 struct file; 37 # endif 38 # include <sys/uio.h> 39 # undef _KERNEL 40 #endif 41 #if defined(_KERNEL) && (__FreeBSD_version >= 220000) 42 # include <sys/filio.h> 43 # include <sys/fcntl.h> 44 # if (__FreeBSD_version >= 300000) && !defined(IPFILTER_LKM) 45 # include "opt_ipfilter.h" 46 # endif 47 #else 48 # include <sys/ioctl.h> 49 #endif 50 #include <sys/time.h> 51 #if !defined(linux) 52 # include <sys/protosw.h> 53 #endif 54 #include <sys/socket.h> 55 #if defined(_KERNEL) 56 # include <sys/systm.h> 57 # if !defined(__SVR4) && !defined(__svr4__) 58 # include <sys/mbuf.h> 59 # endif 60 #endif 61 #if defined(__SVR4) || defined(__svr4__) 62 # include <sys/filio.h> 63 # include <sys/byteorder.h> 64 # ifdef _KERNEL 65 # include <sys/dditypes.h> 66 # endif 67 # include <sys/stream.h> 68 # include <sys/kmem.h> 69 #endif 70 71 #include <net/if.h> 72 #ifdef sun 73 # include <net/af.h> 74 #endif 75 #include <net/route.h> 76 #include <netinet/in.h> 77 #include <netinet/in_systm.h> 78 #include <netinet/ip.h> 79 #include <netinet/tcp.h> 80 #if !defined(linux) 81 # include <netinet/ip_var.h> 82 #endif 83 #if !defined(__hpux) && !defined(linux) 84 # include <netinet/tcp_fsm.h> 85 #endif 86 #include <netinet/udp.h> 87 #include <netinet/ip_icmp.h> 88 #include "netinet/ip_compat.h" 89 #include <netinet/tcpip.h> 90 #include "netinet/ip_fil.h" 91 #include "netinet/ip_nat.h" 92 #include "netinet/ip_frag.h" 93 #include "netinet/ip_state.h" 94 #include "netinet/ip_proxy.h" 95 #include "netinet/ipf_stack.h" 96 #ifdef IPFILTER_SYNC 97 #include "netinet/ip_sync.h" 98 #endif 99 #ifdef IPFILTER_SCAN 100 #include "netinet/ip_scan.h" 101 #endif 102 #ifdef USE_INET6 103 #include <netinet/icmp6.h> 104 #endif 105 #if (__FreeBSD_version >= 300000) 106 # include <sys/malloc.h> 107 # if defined(_KERNEL) && !defined(IPFILTER_LKM) 108 # include <sys/libkern.h> 109 # include <sys/systm.h> 110 # endif 111 #endif 112 /* END OF INCLUDES */ 113 114 115 #if !defined(lint) 116 static const char sccsid[] = "@(#)ip_state.c 1.8 6/5/96 (C) 1993-2000 Darren Reed"; 117 static const char rcsid[] = "@(#)$Id: ip_state.c,v 2.186.2.36 2005/08/11 19:58:03 darrenr Exp $"; 118 #endif 119 120 #ifdef USE_INET6 121 static ipstate_t *fr_checkicmp6matchingstate __P((fr_info_t *)); 122 #endif 123 static ipstate_t *fr_matchsrcdst __P((fr_info_t *, ipstate_t *, i6addr_t *, 124 i6addr_t *, tcphdr_t *, u_32_t)); 125 static ipstate_t *fr_checkicmpmatchingstate __P((fr_info_t *)); 126 static int fr_state_flush __P((int, int, ipf_stack_t *)); 127 static ips_stat_t *fr_statetstats __P((ipf_stack_t *)); 128 static void fr_delstate __P((ipstate_t *, int, ipf_stack_t *)); 129 static int fr_state_remove __P((caddr_t, ipf_stack_t *)); 130 static void fr_ipsmove __P((ipstate_t *, u_int, ipf_stack_t *)); 131 static int fr_tcpstate __P((fr_info_t *, tcphdr_t *, ipstate_t *)); 132 static int fr_tcpoptions __P((fr_info_t *, tcphdr_t *, tcpdata_t *)); 133 static ipstate_t *fr_stclone __P((fr_info_t *, tcphdr_t *, ipstate_t *)); 134 static void fr_fixinisn __P((fr_info_t *, ipstate_t *)); 135 static void fr_fixoutisn __P((fr_info_t *, ipstate_t *)); 136 static void fr_checknewisn __P((fr_info_t *, ipstate_t *)); 137 static int fr_stateiter __P((ipftoken_t *, ipfgeniter_t *, ipf_stack_t *)); 138 139 int fr_stputent __P((caddr_t, ipf_stack_t *)); 140 int fr_stgetent __P((caddr_t, ipf_stack_t *)); 141 142 #define ONE_DAY IPF_TTLVAL(1 * 86400) /* 1 day */ 143 #define FIVE_DAYS (5 * ONE_DAY) 144 #define DOUBLE_HASH(x, ifs) \ 145 (((x) + ifs->ifs_ips_seed[(x) % ifs->ifs_fr_statesize]) % ifs->ifs_fr_statesize) 146 147 148 149 /* ------------------------------------------------------------------------ */ 150 /* Function: fr_stateinit */ 151 /* Returns: int - 0 == success, -1 == failure */ 152 /* Parameters: Nil */ 153 /* */ 154 /* Initialise all the global variables used within the state code. */ 155 /* This action also includes initiailising locks. */ 156 /* ------------------------------------------------------------------------ */ 157 int fr_stateinit(ifs) 158 ipf_stack_t *ifs; 159 { 160 int i; 161 162 ifs->ifs_fr_tcpidletimeout = FIVE_DAYS; 163 ifs->ifs_fr_tcpclosewait = IPF_TTLVAL(TCP_MSL); 164 ifs->ifs_fr_tcplastack = IPF_TTLVAL(TCP_MSL); 165 ifs->ifs_fr_tcptimeout = IPF_TTLVAL(TCP_MSL); 166 ifs->ifs_fr_tcpclosed = IPF_TTLVAL(60); 167 ifs->ifs_fr_tcphalfclosed = IPF_TTLVAL(2 * 3600); /* 2 hours */ 168 ifs->ifs_fr_udptimeout = IPF_TTLVAL(120); 169 ifs->ifs_fr_udpacktimeout = IPF_TTLVAL(12); 170 ifs->ifs_fr_icmptimeout = IPF_TTLVAL(60); 171 ifs->ifs_fr_icmpacktimeout = IPF_TTLVAL(6); 172 ifs->ifs_fr_iptimeout = IPF_TTLVAL(60); 173 ifs->ifs_fr_statemax = IPSTATE_MAX; 174 ifs->ifs_fr_statesize = IPSTATE_SIZE; 175 ifs->ifs_fr_state_maxbucket_reset = 1; 176 #ifdef IPFILTER_LOG 177 ifs->ifs_ipstate_logging = 1; 178 #else 179 ifs->ifs_ipstate_logging = 0; 180 #endif 181 182 KMALLOCS(ifs->ifs_ips_table, ipstate_t **, 183 ifs->ifs_fr_statesize * sizeof(ipstate_t *)); 184 if (ifs->ifs_ips_table == NULL) 185 return -1; 186 bzero((char *)ifs->ifs_ips_table, 187 ifs->ifs_fr_statesize * sizeof(ipstate_t *)); 188 189 KMALLOCS(ifs->ifs_ips_seed, u_long *, 190 ifs->ifs_fr_statesize * sizeof(*ifs->ifs_ips_seed)); 191 if (ifs->ifs_ips_seed == NULL) 192 return -2; 193 for (i = 0; i < ifs->ifs_fr_statesize; i++) { 194 /* 195 * XXX - ips_seed[X] should be a random number of sorts. 196 */ 197 #if (__FreeBSD_version >= 400000) 198 ifs->ifs_ips_seed[i] = arc4random(); 199 #else 200 ifs->ifs_ips_seed[i] = ((u_long)ifs->ifs_ips_seed + i) * 201 ifs->ifs_fr_statesize; 202 ifs->ifs_ips_seed[i] ^= 0xa5a55a5a; 203 ifs->ifs_ips_seed[i] *= (u_long)ifs->ifs_ips_seed; 204 ifs->ifs_ips_seed[i] ^= 0x5a5aa5a5; 205 ifs->ifs_ips_seed[i] *= ifs->ifs_fr_statemax; 206 #endif 207 } 208 209 /* fill icmp reply type table */ 210 for (i = 0; i <= ICMP_MAXTYPE; i++) 211 icmpreplytype4[i] = -1; 212 icmpreplytype4[ICMP_ECHO] = ICMP_ECHOREPLY; 213 icmpreplytype4[ICMP_TSTAMP] = ICMP_TSTAMPREPLY; 214 icmpreplytype4[ICMP_IREQ] = ICMP_IREQREPLY; 215 icmpreplytype4[ICMP_MASKREQ] = ICMP_MASKREPLY; 216 #ifdef USE_INET6 217 /* fill icmp reply type table */ 218 for (i = 0; i <= ICMP6_MAXTYPE; i++) 219 icmpreplytype6[i] = -1; 220 icmpreplytype6[ICMP6_ECHO_REQUEST] = ICMP6_ECHO_REPLY; 221 icmpreplytype6[ICMP6_MEMBERSHIP_QUERY] = ICMP6_MEMBERSHIP_REPORT; 222 icmpreplytype6[ICMP6_NI_QUERY] = ICMP6_NI_REPLY; 223 icmpreplytype6[ND_ROUTER_SOLICIT] = ND_ROUTER_ADVERT; 224 icmpreplytype6[ND_NEIGHBOR_SOLICIT] = ND_NEIGHBOR_ADVERT; 225 #endif 226 227 KMALLOCS(ifs->ifs_ips_stats.iss_bucketlen, u_long *, 228 ifs->ifs_fr_statesize * sizeof(u_long)); 229 if (ifs->ifs_ips_stats.iss_bucketlen == NULL) 230 return -1; 231 bzero((char *)ifs->ifs_ips_stats.iss_bucketlen, 232 ifs->ifs_fr_statesize * sizeof(u_long)); 233 234 if (ifs->ifs_fr_state_maxbucket == 0) { 235 for (i = ifs->ifs_fr_statesize; i > 0; i >>= 1) 236 ifs->ifs_fr_state_maxbucket++; 237 ifs->ifs_fr_state_maxbucket *= 2; 238 } 239 240 fr_sttab_init(ifs->ifs_ips_tqtqb, ifs); 241 ifs->ifs_ips_tqtqb[IPF_TCP_NSTATES - 1].ifq_next = &ifs->ifs_ips_udptq; 242 ifs->ifs_ips_udptq.ifq_ttl = (u_long)ifs->ifs_fr_udptimeout; 243 ifs->ifs_ips_udptq.ifq_ref = 1; 244 ifs->ifs_ips_udptq.ifq_head = NULL; 245 ifs->ifs_ips_udptq.ifq_tail = &ifs->ifs_ips_udptq.ifq_head; 246 MUTEX_INIT(&ifs->ifs_ips_udptq.ifq_lock, "ipftq udp tab"); 247 ifs->ifs_ips_udptq.ifq_next = &ifs->ifs_ips_udpacktq; 248 ifs->ifs_ips_udpacktq.ifq_ttl = (u_long)ifs->ifs_fr_udpacktimeout; 249 ifs->ifs_ips_udpacktq.ifq_ref = 1; 250 ifs->ifs_ips_udpacktq.ifq_head = NULL; 251 ifs->ifs_ips_udpacktq.ifq_tail = &ifs->ifs_ips_udpacktq.ifq_head; 252 MUTEX_INIT(&ifs->ifs_ips_udpacktq.ifq_lock, "ipftq udpack tab"); 253 ifs->ifs_ips_udpacktq.ifq_next = &ifs->ifs_ips_icmptq; 254 ifs->ifs_ips_icmptq.ifq_ttl = (u_long)ifs->ifs_fr_icmptimeout; 255 ifs->ifs_ips_icmptq.ifq_ref = 1; 256 ifs->ifs_ips_icmptq.ifq_head = NULL; 257 ifs->ifs_ips_icmptq.ifq_tail = &ifs->ifs_ips_icmptq.ifq_head; 258 MUTEX_INIT(&ifs->ifs_ips_icmptq.ifq_lock, "ipftq icmp tab"); 259 ifs->ifs_ips_icmptq.ifq_next = &ifs->ifs_ips_icmpacktq; 260 ifs->ifs_ips_icmpacktq.ifq_ttl = (u_long)ifs->ifs_fr_icmpacktimeout; 261 ifs->ifs_ips_icmpacktq.ifq_ref = 1; 262 ifs->ifs_ips_icmpacktq.ifq_head = NULL; 263 ifs->ifs_ips_icmpacktq.ifq_tail = &ifs->ifs_ips_icmpacktq.ifq_head; 264 MUTEX_INIT(&ifs->ifs_ips_icmpacktq.ifq_lock, "ipftq icmpack tab"); 265 ifs->ifs_ips_icmpacktq.ifq_next = &ifs->ifs_ips_iptq; 266 ifs->ifs_ips_iptq.ifq_ttl = (u_long)ifs->ifs_fr_iptimeout; 267 ifs->ifs_ips_iptq.ifq_ref = 1; 268 ifs->ifs_ips_iptq.ifq_head = NULL; 269 ifs->ifs_ips_iptq.ifq_tail = &ifs->ifs_ips_iptq.ifq_head; 270 MUTEX_INIT(&ifs->ifs_ips_iptq.ifq_lock, "ipftq ip tab"); 271 ifs->ifs_ips_iptq.ifq_next = NULL; 272 273 RWLOCK_INIT(&ifs->ifs_ipf_state, "ipf IP state rwlock"); 274 MUTEX_INIT(&ifs->ifs_ipf_stinsert, "ipf state insert mutex"); 275 ifs->ifs_fr_state_init = 1; 276 277 ifs->ifs_ips_last_force_flush = ifs->ifs_fr_ticks; 278 return 0; 279 } 280 281 282 /* ------------------------------------------------------------------------ */ 283 /* Function: fr_stateunload */ 284 /* Returns: Nil */ 285 /* Parameters: Nil */ 286 /* */ 287 /* Release and destroy any resources acquired or initialised so that */ 288 /* IPFilter can be unloaded or re-initialised. */ 289 /* ------------------------------------------------------------------------ */ 290 void fr_stateunload(ifs) 291 ipf_stack_t *ifs; 292 { 293 ipftq_t *ifq, *ifqnext; 294 ipstate_t *is; 295 296 while ((is = ifs->ifs_ips_list) != NULL) 297 fr_delstate(is, 0, ifs); 298 299 /* 300 * Proxy timeout queues are not cleaned here because although they 301 * exist on the state list, appr_unload is called after fr_stateunload 302 * and the proxies actually are responsible for them being created. 303 * Should the proxy timeouts have their own list? There's no real 304 * justification as this is the only complicationA 305 */ 306 for (ifq = ifs->ifs_ips_utqe; ifq != NULL; ifq = ifqnext) { 307 ifqnext = ifq->ifq_next; 308 if (((ifq->ifq_flags & IFQF_PROXY) == 0) && 309 (fr_deletetimeoutqueue(ifq) == 0)) 310 fr_freetimeoutqueue(ifq, ifs); 311 } 312 313 ifs->ifs_ips_stats.iss_inuse = 0; 314 ifs->ifs_ips_num = 0; 315 316 if (ifs->ifs_fr_state_init == 1) { 317 fr_sttab_destroy(ifs->ifs_ips_tqtqb); 318 MUTEX_DESTROY(&ifs->ifs_ips_udptq.ifq_lock); 319 MUTEX_DESTROY(&ifs->ifs_ips_icmptq.ifq_lock); 320 MUTEX_DESTROY(&ifs->ifs_ips_udpacktq.ifq_lock); 321 MUTEX_DESTROY(&ifs->ifs_ips_icmpacktq.ifq_lock); 322 MUTEX_DESTROY(&ifs->ifs_ips_iptq.ifq_lock); 323 } 324 325 if (ifs->ifs_ips_table != NULL) { 326 KFREES(ifs->ifs_ips_table, 327 ifs->ifs_fr_statesize * sizeof(*ifs->ifs_ips_table)); 328 ifs->ifs_ips_table = NULL; 329 } 330 331 if (ifs->ifs_ips_seed != NULL) { 332 KFREES(ifs->ifs_ips_seed, 333 ifs->ifs_fr_statesize * sizeof(*ifs->ifs_ips_seed)); 334 ifs->ifs_ips_seed = NULL; 335 } 336 337 if (ifs->ifs_ips_stats.iss_bucketlen != NULL) { 338 KFREES(ifs->ifs_ips_stats.iss_bucketlen, 339 ifs->ifs_fr_statesize * sizeof(u_long)); 340 ifs->ifs_ips_stats.iss_bucketlen = NULL; 341 } 342 343 if (ifs->ifs_fr_state_maxbucket_reset == 1) 344 ifs->ifs_fr_state_maxbucket = 0; 345 346 if (ifs->ifs_fr_state_init == 1) { 347 ifs->ifs_fr_state_init = 0; 348 RW_DESTROY(&ifs->ifs_ipf_state); 349 MUTEX_DESTROY(&ifs->ifs_ipf_stinsert); 350 } 351 } 352 353 354 /* ------------------------------------------------------------------------ */ 355 /* Function: fr_statetstats */ 356 /* Returns: ips_state_t* - pointer to state stats structure */ 357 /* Parameters: Nil */ 358 /* */ 359 /* Put all the current numbers and pointers into a single struct and return */ 360 /* a pointer to it. */ 361 /* ------------------------------------------------------------------------ */ 362 static ips_stat_t *fr_statetstats(ifs) 363 ipf_stack_t *ifs; 364 { 365 ifs->ifs_ips_stats.iss_active = ifs->ifs_ips_num; 366 ifs->ifs_ips_stats.iss_statesize = ifs->ifs_fr_statesize; 367 ifs->ifs_ips_stats.iss_statemax = ifs->ifs_fr_statemax; 368 ifs->ifs_ips_stats.iss_table = ifs->ifs_ips_table; 369 ifs->ifs_ips_stats.iss_list = ifs->ifs_ips_list; 370 ifs->ifs_ips_stats.iss_ticks = ifs->ifs_fr_ticks; 371 return &ifs->ifs_ips_stats; 372 } 373 374 /* ------------------------------------------------------------------------ */ 375 /* Function: fr_state_remove */ 376 /* Returns: int - 0 == success, != 0 == failure */ 377 /* Parameters: data(I) - pointer to state structure to delete from table */ 378 /* */ 379 /* Search for a state structure that matches the one passed, according to */ 380 /* the IP addresses and other protocol specific information. */ 381 /* ------------------------------------------------------------------------ */ 382 static int fr_state_remove(data, ifs) 383 caddr_t data; 384 ipf_stack_t *ifs; 385 { 386 ipstate_t *sp, st; 387 int error; 388 389 sp = &st; 390 error = fr_inobj(data, &st, IPFOBJ_IPSTATE); 391 if (error) 392 return EFAULT; 393 394 WRITE_ENTER(&ifs->ifs_ipf_state); 395 for (sp = ifs->ifs_ips_list; sp; sp = sp->is_next) 396 if ((sp->is_p == st.is_p) && (sp->is_v == st.is_v) && 397 !bcmp((caddr_t)&sp->is_src, (caddr_t)&st.is_src, 398 sizeof(st.is_src)) && 399 !bcmp((caddr_t)&sp->is_dst, (caddr_t)&st.is_src, 400 sizeof(st.is_dst)) && 401 !bcmp((caddr_t)&sp->is_ps, (caddr_t)&st.is_ps, 402 sizeof(st.is_ps))) { 403 fr_delstate(sp, ISL_REMOVE, ifs); 404 RWLOCK_EXIT(&ifs->ifs_ipf_state); 405 return 0; 406 } 407 RWLOCK_EXIT(&ifs->ifs_ipf_state); 408 return ESRCH; 409 } 410 411 412 /* ------------------------------------------------------------------------ */ 413 /* Function: fr_state_ioctl */ 414 /* Returns: int - 0 == success, != 0 == failure */ 415 /* Parameters: data(I) - pointer to ioctl data */ 416 /* cmd(I) - ioctl command integer */ 417 /* mode(I) - file mode bits used with open */ 418 /* */ 419 /* Processes an ioctl call made to operate on the IP Filter state device. */ 420 /* ------------------------------------------------------------------------ */ 421 int fr_state_ioctl(data, cmd, mode, uid, ctx, ifs) 422 caddr_t data; 423 ioctlcmd_t cmd; 424 int mode, uid; 425 void *ctx; 426 ipf_stack_t *ifs; 427 { 428 int arg, ret, error = 0; 429 430 switch (cmd) 431 { 432 /* 433 * Delete an entry from the state table. 434 */ 435 case SIOCDELST : 436 error = fr_state_remove(data, ifs); 437 break; 438 /* 439 * Flush the state table 440 */ 441 case SIOCIPFFL : 442 BCOPYIN(data, (char *)&arg, sizeof(arg)); 443 if (arg == 0 || arg == 1) { 444 WRITE_ENTER(&ifs->ifs_ipf_state); 445 ret = fr_state_flush(arg, 4, ifs); 446 RWLOCK_EXIT(&ifs->ifs_ipf_state); 447 BCOPYOUT((char *)&ret, data, sizeof(ret)); 448 } else 449 error = EINVAL; 450 break; 451 #ifdef USE_INET6 452 case SIOCIPFL6 : 453 BCOPYIN(data, (char *)&arg, sizeof(arg)); 454 if (arg == 0 || arg == 1) { 455 WRITE_ENTER(&ifs->ifs_ipf_state); 456 ret = fr_state_flush(arg, 6, ifs); 457 RWLOCK_EXIT(&ifs->ifs_ipf_state); 458 BCOPYOUT((char *)&ret, data, sizeof(ret)); 459 } else 460 error = EINVAL; 461 break; 462 #endif 463 #ifdef IPFILTER_LOG 464 /* 465 * Flush the state log. 466 */ 467 case SIOCIPFFB : 468 if (!(mode & FWRITE)) 469 error = EPERM; 470 else { 471 int tmp; 472 473 tmp = ipflog_clear(IPL_LOGSTATE, ifs); 474 BCOPYOUT((char *)&tmp, data, sizeof(tmp)); 475 } 476 break; 477 /* 478 * Turn logging of state information on/off. 479 */ 480 case SIOCSETLG : 481 if (!(mode & FWRITE)) 482 error = EPERM; 483 else { 484 BCOPYIN((char *)data, 485 (char *)&ifs->ifs_ipstate_logging, 486 sizeof(ifs->ifs_ipstate_logging)); 487 } 488 break; 489 /* 490 * Return the current state of logging. 491 */ 492 case SIOCGETLG : 493 BCOPYOUT((char *)&ifs->ifs_ipstate_logging, (char *)data, 494 sizeof(ifs->ifs_ipstate_logging)); 495 break; 496 /* 497 * Return the number of bytes currently waiting to be read. 498 */ 499 case FIONREAD : 500 arg = ifs->ifs_iplused[IPL_LOGSTATE]; /* returned in an int */ 501 BCOPYOUT((char *)&arg, data, sizeof(arg)); 502 break; 503 #endif 504 /* 505 * Get the current state statistics. 506 */ 507 case SIOCGETFS : 508 error = fr_outobj(data, fr_statetstats(ifs), IPFOBJ_STATESTAT); 509 break; 510 /* 511 * Lock/Unlock the state table. (Locking prevents any changes, which 512 * means no packets match). 513 */ 514 case SIOCSTLCK : 515 if (!(mode & FWRITE)) { 516 error = EPERM; 517 } else { 518 fr_lock(data, &ifs->ifs_fr_state_lock); 519 } 520 break; 521 /* 522 * Add an entry to the current state table. 523 */ 524 case SIOCSTPUT : 525 if (!ifs->ifs_fr_state_lock || !(mode &FWRITE)) { 526 error = EACCES; 527 break; 528 } 529 error = fr_stputent(data, ifs); 530 break; 531 /* 532 * Get a state table entry. 533 */ 534 case SIOCSTGET : 535 if (!ifs->ifs_fr_state_lock) { 536 error = EACCES; 537 break; 538 } 539 error = fr_stgetent(data, ifs); 540 break; 541 542 case SIOCGENITER : 543 { 544 ipftoken_t *token; 545 ipfgeniter_t iter; 546 547 error = fr_inobj(data, &iter, IPFOBJ_GENITER); 548 if (error != 0) 549 break; 550 551 token = ipf_findtoken(IPFGENITER_STATE, uid, ctx, ifs); 552 if (token != NULL) 553 error = fr_stateiter(token, &iter, ifs); 554 else 555 error = ESRCH; 556 RWLOCK_EXIT(&ifs->ifs_ipf_tokens); 557 break; 558 } 559 560 case SIOCIPFDELTOK : 561 (void) BCOPYIN(data, (char *)&arg, sizeof(arg)); 562 error = ipf_deltoken(arg, uid, ctx, ifs); 563 break; 564 565 default : 566 error = EINVAL; 567 break; 568 } 569 return error; 570 } 571 572 573 /* ------------------------------------------------------------------------ */ 574 /* Function: fr_stgetent */ 575 /* Returns: int - 0 == success, != 0 == failure */ 576 /* Parameters: data(I) - pointer to state structure to retrieve from table */ 577 /* */ 578 /* Copy out state information from the kernel to a user space process. If */ 579 /* there is a filter rule associated with the state entry, copy that out */ 580 /* as well. The entry to copy out is taken from the value of "ips_next" in */ 581 /* the struct passed in and if not null and not found in the list of current*/ 582 /* state entries, the retrieval fails. */ 583 /* ------------------------------------------------------------------------ */ 584 int fr_stgetent(data, ifs) 585 caddr_t data; 586 ipf_stack_t *ifs; 587 { 588 ipstate_t *is, *isn; 589 ipstate_save_t ips; 590 int error; 591 592 error = fr_inobj(data, &ips, IPFOBJ_STATESAVE); 593 if (error) 594 return EFAULT; 595 596 isn = ips.ips_next; 597 if (isn == NULL) { 598 isn = ifs->ifs_ips_list; 599 if (isn == NULL) { 600 if (ips.ips_next == NULL) 601 return ENOENT; 602 return 0; 603 } 604 } else { 605 /* 606 * Make sure the pointer we're copying from exists in the 607 * current list of entries. Security precaution to prevent 608 * copying of random kernel data. 609 */ 610 for (is = ifs->ifs_ips_list; is; is = is->is_next) 611 if (is == isn) 612 break; 613 if (!is) 614 return ESRCH; 615 } 616 ips.ips_next = isn->is_next; 617 bcopy((char *)isn, (char *)&ips.ips_is, sizeof(ips.ips_is)); 618 ips.ips_rule = isn->is_rule; 619 if (isn->is_rule != NULL) 620 bcopy((char *)isn->is_rule, (char *)&ips.ips_fr, 621 sizeof(ips.ips_fr)); 622 error = fr_outobj(data, &ips, IPFOBJ_STATESAVE); 623 if (error) 624 return EFAULT; 625 return 0; 626 } 627 628 629 /* ------------------------------------------------------------------------ */ 630 /* Function: fr_stputent */ 631 /* Returns: int - 0 == success, != 0 == failure */ 632 /* Parameters: data(I) - pointer to state information struct */ 633 /* */ 634 /* This function implements the SIOCSTPUT ioctl: insert a state entry into */ 635 /* the state table. If the state info. includes a pointer to a filter rule */ 636 /* then also add in an orphaned rule (will not show up in any "ipfstat -io" */ 637 /* output. */ 638 /* ------------------------------------------------------------------------ */ 639 int fr_stputent(data, ifs) 640 caddr_t data; 641 ipf_stack_t *ifs; 642 { 643 ipstate_t *is, *isn; 644 ipstate_save_t ips; 645 int error, i; 646 frentry_t *fr; 647 char *name; 648 649 error = fr_inobj(data, &ips, IPFOBJ_STATESAVE); 650 if (error) 651 return EFAULT; 652 653 KMALLOC(isn, ipstate_t *); 654 if (isn == NULL) 655 return ENOMEM; 656 657 bcopy((char *)&ips.ips_is, (char *)isn, sizeof(*isn)); 658 bzero((char *)isn, offsetof(struct ipstate, is_pkts)); 659 isn->is_sti.tqe_pnext = NULL; 660 isn->is_sti.tqe_next = NULL; 661 isn->is_sti.tqe_ifq = NULL; 662 isn->is_sti.tqe_parent = isn; 663 isn->is_ifp[0] = NULL; 664 isn->is_ifp[1] = NULL; 665 isn->is_ifp[2] = NULL; 666 isn->is_ifp[3] = NULL; 667 isn->is_sync = NULL; 668 fr = ips.ips_rule; 669 670 if (fr == NULL) { 671 READ_ENTER(&ifs->ifs_ipf_state); 672 fr_stinsert(isn, 0, ifs); 673 MUTEX_EXIT(&isn->is_lock); 674 RWLOCK_EXIT(&ifs->ifs_ipf_state); 675 return 0; 676 } 677 678 if (isn->is_flags & SI_NEWFR) { 679 KMALLOC(fr, frentry_t *); 680 if (fr == NULL) { 681 KFREE(isn); 682 return ENOMEM; 683 } 684 bcopy((char *)&ips.ips_fr, (char *)fr, sizeof(*fr)); 685 isn->is_rule = fr; 686 ips.ips_is.is_rule = fr; 687 MUTEX_NUKE(&fr->fr_lock); 688 MUTEX_INIT(&fr->fr_lock, "state filter rule lock"); 689 690 /* 691 * Look up all the interface names in the rule. 692 */ 693 for (i = 0; i < 4; i++) { 694 name = fr->fr_ifnames[i]; 695 fr->fr_ifas[i] = fr_resolvenic(name, fr->fr_v, ifs); 696 name = isn->is_ifname[i]; 697 isn->is_ifp[i] = fr_resolvenic(name, isn->is_v, ifs); 698 } 699 700 fr->fr_ref = 0; 701 fr->fr_dsize = 0; 702 fr->fr_data = NULL; 703 704 fr_resolvedest(&fr->fr_tif, fr->fr_v, ifs); 705 fr_resolvedest(&fr->fr_dif, fr->fr_v, ifs); 706 707 /* 708 * send a copy back to userland of what we ended up 709 * to allow for verification. 710 */ 711 error = fr_outobj(data, &ips, IPFOBJ_STATESAVE); 712 if (error) { 713 KFREE(isn); 714 MUTEX_DESTROY(&fr->fr_lock); 715 KFREE(fr); 716 return EFAULT; 717 } 718 READ_ENTER(&ifs->ifs_ipf_state); 719 fr_stinsert(isn, 0, ifs); 720 MUTEX_EXIT(&isn->is_lock); 721 RWLOCK_EXIT(&ifs->ifs_ipf_state); 722 723 } else { 724 READ_ENTER(&ifs->ifs_ipf_state); 725 for (is = ifs->ifs_ips_list; is; is = is->is_next) 726 if (is->is_rule == fr) { 727 fr_stinsert(isn, 0, ifs); 728 MUTEX_EXIT(&isn->is_lock); 729 break; 730 } 731 732 if (is == NULL) { 733 KFREE(isn); 734 isn = NULL; 735 } 736 RWLOCK_EXIT(&ifs->ifs_ipf_state); 737 738 return (isn == NULL) ? ESRCH : 0; 739 } 740 741 return 0; 742 } 743 744 745 /* ------------------------------------------------------------------------ */ 746 /* Function: fr_stinsert */ 747 /* Returns: Nil */ 748 /* Parameters: is(I) - pointer to state structure */ 749 /* rev(I) - flag indicating forward/reverse direction of packet */ 750 /* */ 751 /* Inserts a state structure into the hash table (for lookups) and the list */ 752 /* of state entries (for enumeration). Resolves all of the interface names */ 753 /* to pointers and adjusts running stats for the hash table as appropriate. */ 754 /* */ 755 /* Locking: it is assumed that some kind of lock on ipf_state is held. */ 756 /* Exits with is_lock initialised and held. */ 757 /* ------------------------------------------------------------------------ */ 758 void fr_stinsert(is, rev, ifs) 759 ipstate_t *is; 760 int rev; 761 ipf_stack_t *ifs; 762 { 763 frentry_t *fr; 764 u_int hv; 765 int i; 766 767 MUTEX_INIT(&is->is_lock, "ipf state entry"); 768 769 fr = is->is_rule; 770 if (fr != NULL) { 771 MUTEX_ENTER(&fr->fr_lock); 772 fr->fr_ref++; 773 fr->fr_statecnt++; 774 MUTEX_EXIT(&fr->fr_lock); 775 } 776 777 /* 778 * Look up all the interface names in the state entry. 779 */ 780 for (i = 0; i < 4; i++) { 781 if (is->is_ifp[i] != NULL) 782 continue; 783 is->is_ifp[i] = fr_resolvenic(is->is_ifname[i], is->is_v, ifs); 784 } 785 786 /* 787 * If we could trust is_hv, then the modulous would not be needed, but 788 * when running with IPFILTER_SYNC, this stops bad values. 789 */ 790 hv = is->is_hv % ifs->ifs_fr_statesize; 791 is->is_hv = hv; 792 793 /* 794 * We need to get both of these locks...the first because it is 795 * possible that once the insert is complete another packet might 796 * come along, match the entry and want to update it. 797 */ 798 MUTEX_ENTER(&is->is_lock); 799 MUTEX_ENTER(&ifs->ifs_ipf_stinsert); 800 801 /* 802 * add into list table. 803 */ 804 if (ifs->ifs_ips_list != NULL) 805 ifs->ifs_ips_list->is_pnext = &is->is_next; 806 is->is_pnext = &ifs->ifs_ips_list; 807 is->is_next = ifs->ifs_ips_list; 808 ifs->ifs_ips_list = is; 809 810 if (ifs->ifs_ips_table[hv] != NULL) 811 ifs->ifs_ips_table[hv]->is_phnext = &is->is_hnext; 812 else 813 ifs->ifs_ips_stats.iss_inuse++; 814 is->is_phnext = ifs->ifs_ips_table + hv; 815 is->is_hnext = ifs->ifs_ips_table[hv]; 816 ifs->ifs_ips_table[hv] = is; 817 ifs->ifs_ips_stats.iss_bucketlen[hv]++; 818 ifs->ifs_ips_num++; 819 MUTEX_EXIT(&ifs->ifs_ipf_stinsert); 820 821 fr_setstatequeue(is, rev, ifs); 822 } 823 824 825 /* ------------------------------------------------------------------------ */ 826 /* Function: fr_addstate */ 827 /* Returns: ipstate_t* - NULL == failure, else pointer to new state */ 828 /* Parameters: fin(I) - pointer to packet information */ 829 /* stsave(O) - pointer to place to save pointer to created */ 830 /* state structure. */ 831 /* flags(I) - flags to use when creating the structure */ 832 /* */ 833 /* Creates a new IP state structure from the packet information collected. */ 834 /* Inserts it into the state table and appends to the bottom of the active */ 835 /* list. If the capacity of the table has reached the maximum allowed then */ 836 /* the call will fail and a flush is scheduled for the next timeout call. */ 837 /* ------------------------------------------------------------------------ */ 838 ipstate_t *fr_addstate(fin, stsave, flags) 839 fr_info_t *fin; 840 ipstate_t **stsave; 841 u_int flags; 842 { 843 ipstate_t *is, ips; 844 struct icmp *ic; 845 u_int pass, hv; 846 frentry_t *fr; 847 tcphdr_t *tcp; 848 grehdr_t *gre; 849 void *ifp; 850 int out; 851 ipf_stack_t *ifs = fin->fin_ifs; 852 853 if (ifs->ifs_fr_state_lock || 854 (fin->fin_flx & (FI_SHORT|FI_STATE|FI_FRAGBODY|FI_BAD))) 855 return NULL; 856 857 if ((fin->fin_flx & FI_OOW) && !(fin->fin_tcpf & TH_SYN)) 858 return NULL; 859 860 /* 861 * If a "keep state" rule has reached the maximum number of references 862 * to it, then schedule an automatic flush in case we can clear out 863 * some "dead old wood". Note that because the lock isn't held on 864 * fr it is possible that we could overflow. The cost of overflowing 865 * is being ignored here as the number by which it can overflow is 866 * a product of the number of simultaneous threads that could be 867 * executing in here, so a limit of 100 won't result in 200, but could 868 * result in 101 or 102. 869 */ 870 fr = fin->fin_fr; 871 if (fr != NULL) { 872 if ((ifs->ifs_ips_num == ifs->ifs_fr_statemax) && (fr->fr_statemax == 0)) { 873 ATOMIC_INCL(ifs->ifs_ips_stats.iss_max); 874 ifs->ifs_fr_state_doflush = 1; 875 return NULL; 876 } 877 if ((fr->fr_statemax != 0) && 878 (fr->fr_statecnt >= fr->fr_statemax)) { 879 ATOMIC_INCL(ifs->ifs_ips_stats.iss_maxref); 880 ifs->ifs_fr_state_doflush = 1; 881 return NULL; 882 } 883 } 884 885 pass = (fr == NULL) ? 0 : fr->fr_flags; 886 887 ic = NULL; 888 tcp = NULL; 889 out = fin->fin_out; 890 is = &ips; 891 bzero((char *)is, sizeof(*is)); 892 is->is_die = 1 + ifs->ifs_fr_ticks; 893 894 /* 895 * Copy and calculate... 896 */ 897 hv = (is->is_p = fin->fin_fi.fi_p); 898 is->is_src = fin->fin_fi.fi_src; 899 hv += is->is_saddr; 900 is->is_dst = fin->fin_fi.fi_dst; 901 hv += is->is_daddr; 902 #ifdef USE_INET6 903 if (fin->fin_v == 6) { 904 /* 905 * For ICMPv6, we check to see if the destination address is 906 * a multicast address. If it is, do not include it in the 907 * calculation of the hash because the correct reply will come 908 * back from a real address, not a multicast address. 909 */ 910 if ((is->is_p == IPPROTO_ICMPV6) && 911 IN6_IS_ADDR_MULTICAST(&is->is_dst.in6)) { 912 /* 913 * So you can do keep state with neighbour discovery. 914 * 915 * Here we could use the address from the neighbour 916 * solicit message to put in the state structure and 917 * we could use that without a wildcard flag too... 918 */ 919 is->is_flags |= SI_W_DADDR; 920 hv -= is->is_daddr; 921 } else { 922 hv += is->is_dst.i6[1]; 923 hv += is->is_dst.i6[2]; 924 hv += is->is_dst.i6[3]; 925 } 926 hv += is->is_src.i6[1]; 927 hv += is->is_src.i6[2]; 928 hv += is->is_src.i6[3]; 929 } 930 #endif 931 932 switch (is->is_p) 933 { 934 #ifdef USE_INET6 935 case IPPROTO_ICMPV6 : 936 ic = fin->fin_dp; 937 938 switch (ic->icmp_type) 939 { 940 case ICMP6_ECHO_REQUEST : 941 is->is_icmp.ici_type = ic->icmp_type; 942 hv += (is->is_icmp.ici_id = ic->icmp_id); 943 break; 944 case ICMP6_MEMBERSHIP_QUERY : 945 case ND_ROUTER_SOLICIT : 946 case ND_NEIGHBOR_SOLICIT : 947 case ICMP6_NI_QUERY : 948 is->is_icmp.ici_type = ic->icmp_type; 949 break; 950 default : 951 return NULL; 952 } 953 ATOMIC_INCL(ifs->ifs_ips_stats.iss_icmp); 954 break; 955 #endif 956 case IPPROTO_ICMP : 957 ic = fin->fin_dp; 958 959 switch (ic->icmp_type) 960 { 961 case ICMP_ECHO : 962 case ICMP_TSTAMP : 963 case ICMP_IREQ : 964 case ICMP_MASKREQ : 965 is->is_icmp.ici_type = ic->icmp_type; 966 hv += (is->is_icmp.ici_id = ic->icmp_id); 967 break; 968 default : 969 return NULL; 970 } 971 ATOMIC_INCL(ifs->ifs_ips_stats.iss_icmp); 972 break; 973 974 case IPPROTO_GRE : 975 gre = fin->fin_dp; 976 977 is->is_gre.gs_flags = gre->gr_flags; 978 is->is_gre.gs_ptype = gre->gr_ptype; 979 if (GRE_REV(is->is_gre.gs_flags) == 1) { 980 is->is_call[0] = fin->fin_data[0]; 981 is->is_call[1] = fin->fin_data[1]; 982 } 983 break; 984 985 case IPPROTO_TCP : 986 tcp = fin->fin_dp; 987 988 if (tcp->th_flags & TH_RST) 989 return NULL; 990 /* 991 * The endian of the ports doesn't matter, but the ack and 992 * sequence numbers do as we do mathematics on them later. 993 */ 994 is->is_sport = htons(fin->fin_data[0]); 995 is->is_dport = htons(fin->fin_data[1]); 996 if ((flags & (SI_W_DPORT|SI_W_SPORT)) == 0) { 997 hv += is->is_sport; 998 hv += is->is_dport; 999 } 1000 1001 /* 1002 * If this is a real packet then initialise fields in the 1003 * state information structure from the TCP header information. 1004 */ 1005 1006 is->is_maxdwin = 1; 1007 is->is_maxswin = ntohs(tcp->th_win); 1008 if (is->is_maxswin == 0) 1009 is->is_maxswin = 1; 1010 1011 if ((fin->fin_flx & FI_IGNORE) == 0) { 1012 is->is_send = ntohl(tcp->th_seq) + fin->fin_dlen - 1013 (TCP_OFF(tcp) << 2) + 1014 ((tcp->th_flags & TH_SYN) ? 1 : 0) + 1015 ((tcp->th_flags & TH_FIN) ? 1 : 0); 1016 is->is_maxsend = is->is_send; 1017 1018 /* 1019 * Window scale option is only present in 1020 * SYN/SYN-ACK packet. 1021 */ 1022 if ((tcp->th_flags & ~(TH_FIN|TH_ACK|TH_ECNALL)) == 1023 TH_SYN && 1024 (TCP_OFF(tcp) > (sizeof(tcphdr_t) >> 2))) { 1025 if (fr_tcpoptions(fin, tcp, 1026 &is->is_tcp.ts_data[0])) 1027 is->is_swinflags = TCP_WSCALE_SEEN| 1028 TCP_WSCALE_FIRST; 1029 } 1030 1031 if ((fin->fin_out != 0) && (pass & FR_NEWISN) != 0) { 1032 fr_checknewisn(fin, is); 1033 fr_fixoutisn(fin, is); 1034 } 1035 1036 if ((tcp->th_flags & TH_OPENING) == TH_SYN) 1037 flags |= IS_TCPFSM; 1038 else { 1039 is->is_maxdwin = is->is_maxswin * 2; 1040 is->is_dend = ntohl(tcp->th_ack); 1041 is->is_maxdend = ntohl(tcp->th_ack); 1042 is->is_maxdwin *= 2; 1043 } 1044 } 1045 1046 /* 1047 * If we're creating state for a starting connection, start the 1048 * timer on it as we'll never see an error if it fails to 1049 * connect. 1050 */ 1051 ATOMIC_INCL(ifs->ifs_ips_stats.iss_tcp); 1052 break; 1053 1054 case IPPROTO_UDP : 1055 tcp = fin->fin_dp; 1056 1057 is->is_sport = htons(fin->fin_data[0]); 1058 is->is_dport = htons(fin->fin_data[1]); 1059 if ((flags & (SI_W_DPORT|SI_W_SPORT)) == 0) { 1060 hv += tcp->th_dport; 1061 hv += tcp->th_sport; 1062 } 1063 ATOMIC_INCL(ifs->ifs_ips_stats.iss_udp); 1064 break; 1065 1066 default : 1067 break; 1068 } 1069 hv = DOUBLE_HASH(hv, ifs); 1070 is->is_hv = hv; 1071 is->is_rule = fr; 1072 is->is_flags = flags & IS_INHERITED; 1073 1074 /* 1075 * Look for identical state. 1076 */ 1077 for (is = ifs->ifs_ips_table[is->is_hv % ifs->ifs_fr_statesize]; 1078 is != NULL; 1079 is = is->is_hnext) { 1080 if (bcmp(&ips.is_src, &is->is_src, 1081 offsetof(struct ipstate, is_ps) - 1082 offsetof(struct ipstate, is_src)) == 0) 1083 break; 1084 } 1085 if (is != NULL) 1086 return NULL; 1087 1088 if (ifs->ifs_ips_stats.iss_bucketlen[hv] >= ifs->ifs_fr_state_maxbucket) { 1089 ATOMIC_INCL(ifs->ifs_ips_stats.iss_bucketfull); 1090 return NULL; 1091 } 1092 KMALLOC(is, ipstate_t *); 1093 if (is == NULL) { 1094 ATOMIC_INCL(ifs->ifs_ips_stats.iss_nomem); 1095 return NULL; 1096 } 1097 bcopy((char *)&ips, (char *)is, sizeof(*is)); 1098 /* 1099 * Do not do the modulous here, it is done in fr_stinsert(). 1100 */ 1101 if (fr != NULL) { 1102 (void) strncpy(is->is_group, fr->fr_group, FR_GROUPLEN); 1103 if (fr->fr_age[0] != 0) { 1104 is->is_tqehead[0] = 1105 fr_addtimeoutqueue(&ifs->ifs_ips_utqe, 1106 fr->fr_age[0], ifs); 1107 is->is_sti.tqe_flags |= TQE_RULEBASED; 1108 } 1109 if (fr->fr_age[1] != 0) { 1110 is->is_tqehead[1] = 1111 fr_addtimeoutqueue(&ifs->ifs_ips_utqe, 1112 fr->fr_age[1], ifs); 1113 is->is_sti.tqe_flags |= TQE_RULEBASED; 1114 } 1115 is->is_tag = fr->fr_logtag; 1116 1117 is->is_ifp[(out << 1) + 1] = fr->fr_ifas[1]; 1118 is->is_ifp[(1 - out) << 1] = fr->fr_ifas[2]; 1119 is->is_ifp[((1 - out) << 1) + 1] = fr->fr_ifas[3]; 1120 1121 if (((ifp = fr->fr_ifas[1]) != NULL) && 1122 (ifp != (void *)-1)) { 1123 COPYIFNAME(ifp, is->is_ifname[(out << 1) + 1], fr->fr_v); 1124 } 1125 if (((ifp = fr->fr_ifas[2]) != NULL) && 1126 (ifp != (void *)-1)) { 1127 COPYIFNAME(ifp, is->is_ifname[(1 - out) << 1], fr->fr_v); 1128 } 1129 if (((ifp = fr->fr_ifas[3]) != NULL) && 1130 (ifp != (void *)-1)) { 1131 COPYIFNAME(ifp, is->is_ifname[((1 - out) << 1) + 1], fr->fr_v); 1132 } 1133 } else { 1134 pass = ifs->ifs_fr_flags; 1135 is->is_tag = FR_NOLOGTAG; 1136 } 1137 1138 is->is_ifp[out << 1] = fin->fin_ifp; 1139 if (fin->fin_ifp != NULL) { 1140 COPYIFNAME(fin->fin_ifp, is->is_ifname[out << 1], fr->fr_v); 1141 } 1142 1143 /* 1144 * It may seem strange to set is_ref to 2, but fr_check() will call 1145 * fr_statederef() after calling fr_addstate() and the idea is to 1146 * have it exist at the end of fr_check() with is_ref == 1. 1147 */ 1148 is->is_ref = 2; 1149 is->is_pass = pass; 1150 is->is_pkts[0] = 0, is->is_bytes[0] = 0; 1151 is->is_pkts[1] = 0, is->is_bytes[1] = 0; 1152 is->is_pkts[2] = 0, is->is_bytes[2] = 0; 1153 is->is_pkts[3] = 0, is->is_bytes[3] = 0; 1154 if ((fin->fin_flx & FI_IGNORE) == 0) { 1155 is->is_pkts[out] = 1; 1156 is->is_bytes[out] = fin->fin_plen; 1157 is->is_flx[out][0] = fin->fin_flx & FI_CMP; 1158 is->is_flx[out][0] &= ~FI_OOW; 1159 } 1160 1161 if (pass & FR_STSTRICT) 1162 is->is_flags |= IS_STRICT; 1163 1164 if (pass & FR_STATESYNC) 1165 is->is_flags |= IS_STATESYNC; 1166 1167 /* 1168 * We want to check everything that is a property of this packet, 1169 * but we don't (automatically) care about it's fragment status as 1170 * this may change. 1171 */ 1172 is->is_v = fin->fin_v; 1173 is->is_opt[0] = fin->fin_optmsk; 1174 is->is_optmsk[0] = 0xffffffff; 1175 is->is_optmsk[1] = 0xffffffff; 1176 if (is->is_v == 6) { 1177 is->is_opt[0] &= ~0x8; 1178 is->is_optmsk[0] &= ~0x8; 1179 is->is_optmsk[1] &= ~0x8; 1180 } 1181 is->is_sec = fin->fin_secmsk; 1182 is->is_secmsk = 0xffff; 1183 is->is_auth = fin->fin_auth; 1184 is->is_authmsk = 0xffff; 1185 if (flags & (SI_WILDP|SI_WILDA)) { 1186 ATOMIC_INCL(ifs->ifs_ips_stats.iss_wild); 1187 } 1188 is->is_rulen = fin->fin_rule; 1189 1190 1191 if (pass & FR_LOGFIRST) 1192 is->is_pass &= ~(FR_LOGFIRST|FR_LOG); 1193 1194 READ_ENTER(&ifs->ifs_ipf_state); 1195 is->is_me = stsave; 1196 1197 fr_stinsert(is, fin->fin_rev, ifs); 1198 1199 if (fin->fin_p == IPPROTO_TCP) { 1200 /* 1201 * If we're creating state for a starting connection, start the 1202 * timer on it as we'll never see an error if it fails to 1203 * connect. 1204 */ 1205 (void) fr_tcp_age(&is->is_sti, fin, ifs->ifs_ips_tqtqb, 1206 is->is_flags); 1207 MUTEX_EXIT(&is->is_lock); 1208 #ifdef IPFILTER_SCAN 1209 if ((is->is_flags & SI_CLONE) == 0) 1210 (void) ipsc_attachis(is); 1211 #endif 1212 } else { 1213 MUTEX_EXIT(&is->is_lock); 1214 } 1215 #ifdef IPFILTER_SYNC 1216 if ((is->is_flags & IS_STATESYNC) && ((is->is_flags & SI_CLONE) == 0)) 1217 is->is_sync = ipfsync_new(SMC_STATE, fin, is); 1218 #endif 1219 if (ifs->ifs_ipstate_logging) 1220 ipstate_log(is, ISL_NEW, ifs); 1221 1222 RWLOCK_EXIT(&ifs->ifs_ipf_state); 1223 fin->fin_state = is; 1224 fin->fin_rev = IP6_NEQ(&is->is_dst, &fin->fin_daddr); 1225 fin->fin_flx |= FI_STATE; 1226 if (fin->fin_flx & FI_FRAG) 1227 (void) fr_newfrag(fin, pass ^ FR_KEEPSTATE); 1228 1229 return is; 1230 } 1231 1232 1233 /* ------------------------------------------------------------------------ */ 1234 /* Function: fr_tcpoptions */ 1235 /* Returns: int - 1 == packet matches state entry, 0 == it does not */ 1236 /* Parameters: fin(I) - pointer to packet information */ 1237 /* tcp(I) - pointer to TCP packet header */ 1238 /* td(I) - pointer to TCP data held as part of the state */ 1239 /* */ 1240 /* Look after the TCP header for any options and deal with those that are */ 1241 /* present. Record details about those that we recogise. */ 1242 /* ------------------------------------------------------------------------ */ 1243 static int fr_tcpoptions(fin, tcp, td) 1244 fr_info_t *fin; 1245 tcphdr_t *tcp; 1246 tcpdata_t *td; 1247 { 1248 int off, mlen, ol, i, len, retval; 1249 char buf[64], *s, opt; 1250 mb_t *m = NULL; 1251 1252 len = (TCP_OFF(tcp) << 2); 1253 if (fin->fin_dlen < len) 1254 return 0; 1255 len -= sizeof(*tcp); 1256 1257 off = fin->fin_plen - fin->fin_dlen + sizeof(*tcp) + fin->fin_ipoff; 1258 1259 m = fin->fin_m; 1260 mlen = MSGDSIZE(m) - off; 1261 if (len > mlen) { 1262 len = mlen; 1263 retval = 0; 1264 } else { 1265 retval = 1; 1266 } 1267 1268 COPYDATA(m, off, len, buf); 1269 1270 for (s = buf; len > 0; ) { 1271 opt = *s; 1272 if (opt == TCPOPT_EOL) 1273 break; 1274 else if (opt == TCPOPT_NOP) 1275 ol = 1; 1276 else { 1277 if (len < 2) 1278 break; 1279 ol = (int)*(s + 1); 1280 if (ol < 2 || ol > len) 1281 break; 1282 1283 /* 1284 * Extract the TCP options we are interested in out of 1285 * the header and store them in the the tcpdata struct. 1286 */ 1287 switch (opt) 1288 { 1289 case TCPOPT_WINDOW : 1290 if (ol == TCPOLEN_WINDOW) { 1291 i = (int)*(s + 2); 1292 if (i > TCP_WSCALE_MAX) 1293 i = TCP_WSCALE_MAX; 1294 else if (i < 0) 1295 i = 0; 1296 td->td_winscale = i; 1297 } 1298 break; 1299 case TCPOPT_MAXSEG : 1300 /* 1301 * So, if we wanted to set the TCP MAXSEG, 1302 * it should be done here... 1303 */ 1304 if (ol == TCPOLEN_MAXSEG) { 1305 i = (int)*(s + 2); 1306 i <<= 8; 1307 i += (int)*(s + 3); 1308 td->td_maxseg = i; 1309 } 1310 break; 1311 } 1312 } 1313 len -= ol; 1314 s += ol; 1315 } 1316 return retval; 1317 } 1318 1319 1320 /* ------------------------------------------------------------------------ */ 1321 /* Function: fr_tcpstate */ 1322 /* Returns: int - 1 == packet matches state entry, 0 == it does not */ 1323 /* Parameters: fin(I) - pointer to packet information */ 1324 /* tcp(I) - pointer to TCP packet header */ 1325 /* is(I) - pointer to master state structure */ 1326 /* */ 1327 /* Check to see if a packet with TCP headers fits within the TCP window. */ 1328 /* Change timeout depending on whether new packet is a SYN-ACK returning */ 1329 /* for a SYN or a RST or FIN which indicate time to close up shop. */ 1330 /* ------------------------------------------------------------------------ */ 1331 static int fr_tcpstate(fin, tcp, is) 1332 fr_info_t *fin; 1333 tcphdr_t *tcp; 1334 ipstate_t *is; 1335 { 1336 int source, ret = 0, flags; 1337 tcpdata_t *fdata, *tdata; 1338 ipf_stack_t *ifs = fin->fin_ifs; 1339 1340 source = !fin->fin_rev; 1341 if (((is->is_flags & IS_TCPFSM) != 0) && (source == 1) && 1342 (ntohs(is->is_sport) != fin->fin_data[0])) 1343 source = 0; 1344 fdata = &is->is_tcp.ts_data[!source]; 1345 tdata = &is->is_tcp.ts_data[source]; 1346 1347 MUTEX_ENTER(&is->is_lock); 1348 if (fr_tcpinwindow(fin, fdata, tdata, tcp, is->is_flags)) { 1349 #ifdef IPFILTER_SCAN 1350 if (is->is_flags & (IS_SC_CLIENT|IS_SC_SERVER)) { 1351 ipsc_packet(fin, is); 1352 if (FR_ISBLOCK(is->is_pass)) { 1353 MUTEX_EXIT(&is->is_lock); 1354 return 1; 1355 } 1356 } 1357 #endif 1358 1359 /* 1360 * Nearing end of connection, start timeout. 1361 */ 1362 ret = fr_tcp_age(&is->is_sti, fin, ifs->ifs_ips_tqtqb, 1363 is->is_flags); 1364 if (ret == 0) { 1365 MUTEX_EXIT(&is->is_lock); 1366 return 0; 1367 } 1368 1369 /* 1370 * set s0's as appropriate. Use syn-ack packet as it 1371 * contains both pieces of required information. 1372 */ 1373 /* 1374 * Window scale option is only present in SYN/SYN-ACK packet. 1375 * Compare with ~TH_FIN to mask out T/TCP setups. 1376 */ 1377 flags = tcp->th_flags & ~(TH_FIN|TH_ECNALL); 1378 if (flags == (TH_SYN|TH_ACK)) { 1379 is->is_s0[source] = ntohl(tcp->th_ack); 1380 is->is_s0[!source] = ntohl(tcp->th_seq) + 1; 1381 if ((TCP_OFF(tcp) > (sizeof(tcphdr_t) >> 2)) && 1382 tdata->td_winscale) { 1383 if (fr_tcpoptions(fin, tcp, fdata)) { 1384 fdata->td_winflags = TCP_WSCALE_SEEN| 1385 TCP_WSCALE_FIRST; 1386 } else { 1387 if (!fdata->td_winscale) 1388 tdata->td_winscale = 0; 1389 } 1390 } 1391 if ((fin->fin_out != 0) && (is->is_pass & FR_NEWISN)) 1392 fr_checknewisn(fin, is); 1393 } else if (flags == TH_SYN) { 1394 is->is_s0[source] = ntohl(tcp->th_seq) + 1; 1395 if ((TCP_OFF(tcp) > (sizeof(tcphdr_t) >> 2))) 1396 if (fr_tcpoptions(fin, tcp, tdata)) { 1397 tdata->td_winflags = TCP_WSCALE_SEEN| 1398 TCP_WSCALE_FIRST; 1399 } 1400 1401 if ((fin->fin_out != 0) && (is->is_pass & FR_NEWISN)) 1402 fr_checknewisn(fin, is); 1403 1404 } 1405 ret = 1; 1406 } else 1407 fin->fin_flx |= FI_OOW; 1408 MUTEX_EXIT(&is->is_lock); 1409 return ret; 1410 } 1411 1412 1413 /* ------------------------------------------------------------------------ */ 1414 /* Function: fr_checknewisn */ 1415 /* Returns: Nil */ 1416 /* Parameters: fin(I) - pointer to packet information */ 1417 /* is(I) - pointer to master state structure */ 1418 /* */ 1419 /* Check to see if this TCP connection is expecting and needs a new */ 1420 /* sequence number for a particular direction of the connection. */ 1421 /* */ 1422 /* NOTE: This does not actually change the sequence numbers, only gets new */ 1423 /* one ready. */ 1424 /* ------------------------------------------------------------------------ */ 1425 static void fr_checknewisn(fin, is) 1426 fr_info_t *fin; 1427 ipstate_t *is; 1428 { 1429 u_32_t sumd, old, new; 1430 tcphdr_t *tcp; 1431 int i; 1432 1433 i = fin->fin_rev; 1434 tcp = fin->fin_dp; 1435 1436 if (((i == 0) && !(is->is_flags & IS_ISNSYN)) || 1437 ((i == 1) && !(is->is_flags & IS_ISNACK))) { 1438 old = ntohl(tcp->th_seq); 1439 new = fr_newisn(fin); 1440 is->is_isninc[i] = new - old; 1441 CALC_SUMD(old, new, sumd); 1442 is->is_sumd[i] = (sumd & 0xffff) + (sumd >> 16); 1443 1444 is->is_flags |= ((i == 0) ? IS_ISNSYN : IS_ISNACK); 1445 } 1446 } 1447 1448 1449 /* ------------------------------------------------------------------------ */ 1450 /* Function: fr_tcpinwindow */ 1451 /* Returns: int - 1 == packet inside TCP "window", 0 == not inside. */ 1452 /* Parameters: fin(I) - pointer to packet information */ 1453 /* fdata(I) - pointer to tcp state informatio (forward) */ 1454 /* tdata(I) - pointer to tcp state informatio (reverse) */ 1455 /* tcp(I) - pointer to TCP packet header */ 1456 /* */ 1457 /* Given a packet has matched addresses and ports, check to see if it is */ 1458 /* within the TCP data window. In a show of generosity, allow packets that */ 1459 /* are within the window space behind the current sequence # as well. */ 1460 /* ------------------------------------------------------------------------ */ 1461 int fr_tcpinwindow(fin, fdata, tdata, tcp, flags) 1462 fr_info_t *fin; 1463 tcpdata_t *fdata, *tdata; 1464 tcphdr_t *tcp; 1465 int flags; 1466 { 1467 tcp_seq seq, ack, end; 1468 int ackskew, tcpflags; 1469 u_32_t win, maxwin; 1470 1471 /* 1472 * Find difference between last checked packet and this packet. 1473 */ 1474 tcpflags = tcp->th_flags; 1475 seq = ntohl(tcp->th_seq); 1476 ack = ntohl(tcp->th_ack); 1477 if (tcpflags & TH_SYN) 1478 win = ntohs(tcp->th_win); 1479 else 1480 win = ntohs(tcp->th_win) << fdata->td_winscale; 1481 if (win == 0) 1482 win = 1; 1483 1484 /* 1485 * if window scaling is present, the scaling is only allowed 1486 * for windows not in the first SYN packet. In that packet the 1487 * window is 65535 to specify the largest window possible 1488 * for receivers not implementing the window scale option. 1489 * Currently, we do not assume TTCP here. That means that 1490 * if we see a second packet from a host (after the initial 1491 * SYN), we can assume that the receiver of the SYN did 1492 * already send back the SYN/ACK (and thus that we know if 1493 * the receiver also does window scaling) 1494 */ 1495 if (!(tcpflags & TH_SYN) && (fdata->td_winflags & TCP_WSCALE_FIRST)) { 1496 if (tdata->td_winflags & TCP_WSCALE_SEEN) { 1497 fdata->td_winflags &= ~TCP_WSCALE_FIRST; 1498 fdata->td_maxwin = win; 1499 } else { 1500 fdata->td_winscale = 0; 1501 fdata->td_winflags = 0; 1502 tdata->td_winscale = 0; 1503 tdata->td_winflags = 0; 1504 } 1505 } 1506 1507 end = seq + fin->fin_dlen - (TCP_OFF(tcp) << 2) + 1508 ((tcpflags & TH_SYN) ? 1 : 0) + ((tcpflags & TH_FIN) ? 1 : 0); 1509 1510 if ((fdata->td_end == 0) && 1511 (!(flags & IS_TCPFSM) || 1512 ((tcpflags & TH_OPENING) == TH_OPENING))) { 1513 /* 1514 * Must be a (outgoing) SYN-ACK in reply to a SYN. 1515 */ 1516 fdata->td_end = end; 1517 fdata->td_maxwin = 1; 1518 fdata->td_maxend = end + win; 1519 } 1520 1521 if (!(tcpflags & TH_ACK)) { /* Pretend an ack was sent */ 1522 ack = tdata->td_end; 1523 } else if (((tcpflags & (TH_ACK|TH_RST)) == (TH_ACK|TH_RST)) && 1524 (ack == 0)) { 1525 /* gross hack to get around certain broken tcp stacks */ 1526 ack = tdata->td_end; 1527 } 1528 1529 if (seq == end) 1530 seq = end = fdata->td_end; 1531 1532 maxwin = tdata->td_maxwin; 1533 ackskew = tdata->td_end - ack; 1534 1535 /* 1536 * Strict sequencing only allows in-order delivery. 1537 */ 1538 if ((flags & IS_STRICT) != 0) { 1539 if (seq != fdata->td_end) { 1540 return 0; 1541 } 1542 } 1543 1544 #define SEQ_GE(a,b) ((int)((a) - (b)) >= 0) 1545 #define SEQ_GT(a,b) ((int)((a) - (b)) > 0) 1546 if ( 1547 #if defined(_KERNEL) 1548 (SEQ_GE(fdata->td_maxend, end)) && 1549 (SEQ_GE(seq, fdata->td_end - maxwin)) && 1550 #endif 1551 /* XXX what about big packets */ 1552 #define MAXACKWINDOW 66000 1553 (-ackskew <= (MAXACKWINDOW << fdata->td_winscale)) && 1554 ( ackskew <= (MAXACKWINDOW << fdata->td_winscale))) { 1555 1556 /* if ackskew < 0 then this should be due to fragmented 1557 * packets. There is no way to know the length of the 1558 * total packet in advance. 1559 * We do know the total length from the fragment cache though. 1560 * Note however that there might be more sessions with 1561 * exactly the same source and destination parameters in the 1562 * state cache (and source and destination is the only stuff 1563 * that is saved in the fragment cache). Note further that 1564 * some TCP connections in the state cache are hashed with 1565 * sport and dport as well which makes it not worthwhile to 1566 * look for them. 1567 * Thus, when ackskew is negative but still seems to belong 1568 * to this session, we bump up the destinations end value. 1569 */ 1570 if (ackskew < 0) 1571 tdata->td_end = ack; 1572 1573 /* update max window seen */ 1574 if (fdata->td_maxwin < win) 1575 fdata->td_maxwin = win; 1576 if (SEQ_GT(end, fdata->td_end)) 1577 fdata->td_end = end; 1578 if (SEQ_GE(ack + win, tdata->td_maxend)) 1579 tdata->td_maxend = ack + win; 1580 return 1; 1581 } 1582 return 0; 1583 } 1584 1585 1586 /* ------------------------------------------------------------------------ */ 1587 /* Function: fr_stclone */ 1588 /* Returns: ipstate_t* - NULL == cloning failed, */ 1589 /* else pointer to new state structure */ 1590 /* Parameters: fin(I) - pointer to packet information */ 1591 /* tcp(I) - pointer to TCP/UDP header */ 1592 /* is(I) - pointer to master state structure */ 1593 /* */ 1594 /* Create a "duplcate" state table entry from the master. */ 1595 /* ------------------------------------------------------------------------ */ 1596 static ipstate_t *fr_stclone(fin, tcp, is) 1597 fr_info_t *fin; 1598 tcphdr_t *tcp; 1599 ipstate_t *is; 1600 { 1601 ipstate_t *clone; 1602 u_32_t send; 1603 ipf_stack_t *ifs = fin->fin_ifs; 1604 1605 if (ifs->ifs_ips_num == ifs->ifs_fr_statemax) { 1606 ATOMIC_INCL(ifs->ifs_ips_stats.iss_max); 1607 ifs->ifs_fr_state_doflush = 1; 1608 return NULL; 1609 } 1610 KMALLOC(clone, ipstate_t *); 1611 if (clone == NULL) 1612 return NULL; 1613 bcopy((char *)is, (char *)clone, sizeof(*clone)); 1614 1615 MUTEX_NUKE(&clone->is_lock); 1616 1617 clone->is_die = ONE_DAY + ifs->ifs_fr_ticks; 1618 clone->is_state[0] = 0; 1619 clone->is_state[1] = 0; 1620 send = ntohl(tcp->th_seq) + fin->fin_dlen - (TCP_OFF(tcp) << 2) + 1621 ((tcp->th_flags & TH_SYN) ? 1 : 0) + 1622 ((tcp->th_flags & TH_FIN) ? 1 : 0); 1623 1624 if (fin->fin_rev == 1) { 1625 clone->is_dend = send; 1626 clone->is_maxdend = send; 1627 clone->is_send = 0; 1628 clone->is_maxswin = 1; 1629 clone->is_maxdwin = ntohs(tcp->th_win); 1630 if (clone->is_maxdwin == 0) 1631 clone->is_maxdwin = 1; 1632 } else { 1633 clone->is_send = send; 1634 clone->is_maxsend = send; 1635 clone->is_dend = 0; 1636 clone->is_maxdwin = 1; 1637 clone->is_maxswin = ntohs(tcp->th_win); 1638 if (clone->is_maxswin == 0) 1639 clone->is_maxswin = 1; 1640 } 1641 1642 clone->is_flags &= ~SI_CLONE; 1643 clone->is_flags |= SI_CLONED; 1644 fr_stinsert(clone, fin->fin_rev, ifs); 1645 clone->is_ref = 2; 1646 if (clone->is_p == IPPROTO_TCP) { 1647 (void) fr_tcp_age(&clone->is_sti, fin, ifs->ifs_ips_tqtqb, 1648 clone->is_flags); 1649 } 1650 MUTEX_EXIT(&clone->is_lock); 1651 #ifdef IPFILTER_SCAN 1652 (void) ipsc_attachis(is); 1653 #endif 1654 #ifdef IPFILTER_SYNC 1655 if (is->is_flags & IS_STATESYNC) 1656 clone->is_sync = ipfsync_new(SMC_STATE, fin, clone); 1657 #endif 1658 return clone; 1659 } 1660 1661 1662 /* ------------------------------------------------------------------------ */ 1663 /* Function: fr_matchsrcdst */ 1664 /* Returns: Nil */ 1665 /* Parameters: fin(I) - pointer to packet information */ 1666 /* is(I) - pointer to state structure */ 1667 /* src(I) - pointer to source address */ 1668 /* dst(I) - pointer to destination address */ 1669 /* tcp(I) - pointer to TCP/UDP header */ 1670 /* */ 1671 /* Match a state table entry against an IP packet. The logic below is that */ 1672 /* ret gets set to one if the match succeeds, else remains 0. If it is */ 1673 /* still 0 after the test. no match. */ 1674 /* ------------------------------------------------------------------------ */ 1675 static ipstate_t *fr_matchsrcdst(fin, is, src, dst, tcp, cmask) 1676 fr_info_t *fin; 1677 ipstate_t *is; 1678 i6addr_t *src, *dst; 1679 tcphdr_t *tcp; 1680 u_32_t cmask; 1681 { 1682 int ret = 0, rev, out, flags, flx = 0, idx; 1683 u_short sp, dp; 1684 u_32_t cflx; 1685 void *ifp; 1686 ipf_stack_t *ifs = fin->fin_ifs; 1687 1688 rev = IP6_NEQ(&is->is_dst, dst); 1689 ifp = fin->fin_ifp; 1690 out = fin->fin_out; 1691 flags = is->is_flags; 1692 sp = 0; 1693 dp = 0; 1694 1695 if (tcp != NULL) { 1696 sp = htons(fin->fin_sport); 1697 dp = ntohs(fin->fin_dport); 1698 } 1699 if (!rev) { 1700 if (tcp != NULL) { 1701 if (!(flags & SI_W_SPORT) && (sp != is->is_sport)) 1702 rev = 1; 1703 else if (!(flags & SI_W_DPORT) && (dp != is->is_dport)) 1704 rev = 1; 1705 } 1706 } 1707 1708 idx = (out << 1) + rev; 1709 1710 /* 1711 * If the interface for this 'direction' is set, make sure it matches. 1712 * An interface name that is not set matches any, as does a name of *. 1713 */ 1714 if ((is->is_ifp[idx] == NULL && 1715 (*is->is_ifname[idx] == '\0' || *is->is_ifname[idx] == '*')) || 1716 is->is_ifp[idx] == ifp) 1717 ret = 1; 1718 1719 if (ret == 0) 1720 return NULL; 1721 ret = 0; 1722 1723 /* 1724 * Match addresses and ports. 1725 */ 1726 if (rev == 0) { 1727 if ((IP6_EQ(&is->is_dst, dst) || (flags & SI_W_DADDR)) && 1728 (IP6_EQ(&is->is_src, src) || (flags & SI_W_SADDR))) { 1729 if (tcp) { 1730 if ((sp == is->is_sport || flags & SI_W_SPORT)&& 1731 (dp == is->is_dport || flags & SI_W_DPORT)) 1732 ret = 1; 1733 } else { 1734 ret = 1; 1735 } 1736 } 1737 } else { 1738 if ((IP6_EQ(&is->is_dst, src) || (flags & SI_W_DADDR)) && 1739 (IP6_EQ(&is->is_src, dst) || (flags & SI_W_SADDR))) { 1740 if (tcp) { 1741 if ((dp == is->is_sport || flags & SI_W_SPORT)&& 1742 (sp == is->is_dport || flags & SI_W_DPORT)) 1743 ret = 1; 1744 } else { 1745 ret = 1; 1746 } 1747 } 1748 } 1749 1750 if (ret == 0) 1751 return NULL; 1752 1753 /* 1754 * Whether or not this should be here, is questionable, but the aim 1755 * is to get this out of the main line. 1756 */ 1757 if (tcp == NULL) 1758 flags = is->is_flags & ~(SI_WILDP|SI_NEWFR|SI_CLONE|SI_CLONED); 1759 1760 /* 1761 * Only one of the source or destination address can be flaged as a 1762 * wildcard. Fill in the missing address, if set. 1763 * For IPv6, if the address being copied in is multicast, then 1764 * don't reset the wild flag - multicast causes it to be set in the 1765 * first place! 1766 */ 1767 if ((flags & (SI_W_SADDR|SI_W_DADDR))) { 1768 fr_ip_t *fi = &fin->fin_fi; 1769 1770 if ((flags & SI_W_SADDR) != 0) { 1771 if (rev == 0) { 1772 #ifdef USE_INET6 1773 if (is->is_v == 6 && 1774 IN6_IS_ADDR_MULTICAST(&fi->fi_src.in6)) 1775 /*EMPTY*/; 1776 else 1777 #endif 1778 { 1779 is->is_src = fi->fi_src; 1780 is->is_flags &= ~SI_W_SADDR; 1781 } 1782 } else { 1783 #ifdef USE_INET6 1784 if (is->is_v == 6 && 1785 IN6_IS_ADDR_MULTICAST(&fi->fi_dst.in6)) 1786 /*EMPTY*/; 1787 else 1788 #endif 1789 { 1790 is->is_src = fi->fi_dst; 1791 is->is_flags &= ~SI_W_SADDR; 1792 } 1793 } 1794 } else if ((flags & SI_W_DADDR) != 0) { 1795 if (rev == 0) { 1796 #ifdef USE_INET6 1797 if (is->is_v == 6 && 1798 IN6_IS_ADDR_MULTICAST(&fi->fi_dst.in6)) 1799 /*EMPTY*/; 1800 else 1801 #endif 1802 { 1803 is->is_dst = fi->fi_dst; 1804 is->is_flags &= ~SI_W_DADDR; 1805 } 1806 } else { 1807 #ifdef USE_INET6 1808 if (is->is_v == 6 && 1809 IN6_IS_ADDR_MULTICAST(&fi->fi_src.in6)) 1810 /*EMPTY*/; 1811 else 1812 #endif 1813 { 1814 is->is_dst = fi->fi_src; 1815 is->is_flags &= ~SI_W_DADDR; 1816 } 1817 } 1818 } 1819 if ((is->is_flags & (SI_WILDA|SI_WILDP)) == 0) { 1820 ATOMIC_DECL(ifs->ifs_ips_stats.iss_wild); 1821 } 1822 } 1823 1824 flx = fin->fin_flx & cmask; 1825 cflx = is->is_flx[out][rev]; 1826 1827 /* 1828 * Match up any flags set from IP options. 1829 */ 1830 if ((cflx && (flx != (cflx & cmask))) || 1831 ((fin->fin_optmsk & is->is_optmsk[rev]) != is->is_opt[rev]) || 1832 ((fin->fin_secmsk & is->is_secmsk) != is->is_sec) || 1833 ((fin->fin_auth & is->is_authmsk) != is->is_auth)) 1834 return NULL; 1835 1836 /* 1837 * Only one of the source or destination port can be flagged as a 1838 * wildcard. When filling it in, fill in a copy of the matched entry 1839 * if it has the cloning flag set. 1840 */ 1841 if ((fin->fin_flx & FI_IGNORE) != 0) { 1842 fin->fin_rev = rev; 1843 return is; 1844 } 1845 1846 if ((flags & (SI_W_SPORT|SI_W_DPORT))) { 1847 if ((flags & SI_CLONE) != 0) { 1848 ipstate_t *clone; 1849 1850 clone = fr_stclone(fin, tcp, is); 1851 if (clone == NULL) 1852 return NULL; 1853 is = clone; 1854 } else { 1855 ATOMIC_DECL(ifs->ifs_ips_stats.iss_wild); 1856 } 1857 1858 if ((flags & SI_W_SPORT) != 0) { 1859 if (rev == 0) { 1860 is->is_sport = sp; 1861 is->is_send = ntohl(tcp->th_seq); 1862 } else { 1863 is->is_sport = dp; 1864 is->is_send = ntohl(tcp->th_ack); 1865 } 1866 is->is_maxsend = is->is_send + 1; 1867 } else if ((flags & SI_W_DPORT) != 0) { 1868 if (rev == 0) { 1869 is->is_dport = dp; 1870 is->is_dend = ntohl(tcp->th_ack); 1871 } else { 1872 is->is_dport = sp; 1873 is->is_dend = ntohl(tcp->th_seq); 1874 } 1875 is->is_maxdend = is->is_dend + 1; 1876 } 1877 is->is_flags &= ~(SI_W_SPORT|SI_W_DPORT); 1878 if ((flags & SI_CLONED) && ifs->ifs_ipstate_logging) 1879 ipstate_log(is, ISL_CLONE, ifs); 1880 } 1881 1882 ret = -1; 1883 1884 if (is->is_flx[out][rev] == 0) { 1885 is->is_flx[out][rev] = flx; 1886 is->is_opt[rev] = fin->fin_optmsk; 1887 if (is->is_v == 6) { 1888 is->is_opt[rev] &= ~0x8; 1889 is->is_optmsk[rev] &= ~0x8; 1890 } 1891 } 1892 1893 /* 1894 * Check if the interface name for this "direction" is set and if not, 1895 * fill it in. 1896 */ 1897 if (is->is_ifp[idx] == NULL && 1898 (*is->is_ifname[idx] == '\0' || *is->is_ifname[idx] == '*')) { 1899 is->is_ifp[idx] = ifp; 1900 COPYIFNAME(ifp, is->is_ifname[idx], fin->fin_v); 1901 } 1902 fin->fin_rev = rev; 1903 return is; 1904 } 1905 1906 1907 /* ------------------------------------------------------------------------ */ 1908 /* Function: fr_checkicmpmatchingstate */ 1909 /* Returns: Nil */ 1910 /* Parameters: fin(I) - pointer to packet information */ 1911 /* */ 1912 /* If we've got an ICMP error message, using the information stored in the */ 1913 /* ICMP packet, look for a matching state table entry. */ 1914 /* */ 1915 /* If we return NULL then no lock on ipf_state is held. */ 1916 /* If we return non-null then a read-lock on ipf_state is held. */ 1917 /* ------------------------------------------------------------------------ */ 1918 static ipstate_t *fr_checkicmpmatchingstate(fin) 1919 fr_info_t *fin; 1920 { 1921 ipstate_t *is, **isp; 1922 u_short sport, dport; 1923 u_char pr; 1924 int backward, i, oi; 1925 i6addr_t dst, src; 1926 struct icmp *ic; 1927 u_short savelen; 1928 icmphdr_t *icmp; 1929 fr_info_t ofin; 1930 tcphdr_t *tcp; 1931 int len; 1932 ip_t *oip; 1933 u_int hv; 1934 ipf_stack_t *ifs = fin->fin_ifs; 1935 1936 /* 1937 * Does it at least have the return (basic) IP header ? 1938 * Is it an actual recognised ICMP error type? 1939 * Only a basic IP header (no options) should be with 1940 * an ICMP error header. 1941 */ 1942 if ((fin->fin_v != 4) || (fin->fin_hlen != sizeof(ip_t)) || 1943 (fin->fin_plen < ICMPERR_MINPKTLEN) || 1944 !(fin->fin_flx & FI_ICMPERR)) 1945 return NULL; 1946 ic = fin->fin_dp; 1947 1948 oip = (ip_t *)((char *)ic + ICMPERR_ICMPHLEN); 1949 /* 1950 * Check if the at least the old IP header (with options) and 1951 * 8 bytes of payload is present. 1952 */ 1953 if (fin->fin_plen < ICMPERR_MAXPKTLEN + ((IP_HL(oip) - 5) << 2)) 1954 return NULL; 1955 1956 /* 1957 * Sanity Checks. 1958 */ 1959 len = fin->fin_dlen - ICMPERR_ICMPHLEN; 1960 if ((len <= 0) || ((IP_HL(oip) << 2) > len)) 1961 return NULL; 1962 1963 /* 1964 * Is the buffer big enough for all of it ? It's the size of the IP 1965 * header claimed in the encapsulated part which is of concern. It 1966 * may be too big to be in this buffer but not so big that it's 1967 * outside the ICMP packet, leading to TCP deref's causing problems. 1968 * This is possible because we don't know how big oip_hl is when we 1969 * do the pullup early in fr_check() and thus can't guarantee it is 1970 * all here now. 1971 */ 1972 #ifdef _KERNEL 1973 { 1974 mb_t *m; 1975 1976 m = fin->fin_m; 1977 # if defined(MENTAT) 1978 if ((char *)oip + len > (char *)m->b_wptr) 1979 return NULL; 1980 # else 1981 if ((char *)oip + len > (char *)fin->fin_ip + m->m_len) 1982 return NULL; 1983 # endif 1984 } 1985 #endif 1986 bcopy((char *)fin, (char *)&ofin, sizeof(*fin)); 1987 1988 /* 1989 * in the IPv4 case we must zero the i6addr union otherwise 1990 * the IP6_EQ and IP6_NEQ macros produce the wrong results because 1991 * of the 'junk' in the unused part of the union 1992 */ 1993 bzero((char *)&src, sizeof(src)); 1994 bzero((char *)&dst, sizeof(dst)); 1995 1996 /* 1997 * we make an fin entry to be able to feed it to 1998 * matchsrcdst note that not all fields are encessary 1999 * but this is the cleanest way. Note further we fill 2000 * in fin_mp such that if someone uses it we'll get 2001 * a kernel panic. fr_matchsrcdst does not use this. 2002 * 2003 * watch out here, as ip is in host order and oip in network 2004 * order. Any change we make must be undone afterwards, like 2005 * oip->ip_off - it is still in network byte order so fix it. 2006 */ 2007 savelen = oip->ip_len; 2008 oip->ip_len = len; 2009 oip->ip_off = ntohs(oip->ip_off); 2010 2011 ofin.fin_flx = FI_NOCKSUM; 2012 ofin.fin_v = 4; 2013 ofin.fin_ip = oip; 2014 ofin.fin_m = NULL; /* if dereferenced, panic XXX */ 2015 ofin.fin_mp = NULL; /* if dereferenced, panic XXX */ 2016 ofin.fin_plen = fin->fin_dlen - ICMPERR_ICMPHLEN; 2017 (void) fr_makefrip(IP_HL(oip) << 2, oip, &ofin); 2018 ofin.fin_ifp = fin->fin_ifp; 2019 ofin.fin_out = !fin->fin_out; 2020 /* 2021 * Reset the short and bad flag here because in fr_matchsrcdst() 2022 * the flags for the current packet (fin_flx) are compared against 2023 * those for the existing session. 2024 */ 2025 ofin.fin_flx &= ~(FI_BAD|FI_SHORT); 2026 2027 /* 2028 * Put old values of ip_len and ip_off back as we don't know 2029 * if we have to forward the packet (or process it again. 2030 */ 2031 oip->ip_len = savelen; 2032 oip->ip_off = htons(oip->ip_off); 2033 2034 switch (oip->ip_p) 2035 { 2036 case IPPROTO_ICMP : 2037 /* 2038 * an ICMP error can only be generated as a result of an 2039 * ICMP query, not as the response on an ICMP error 2040 * 2041 * XXX theoretically ICMP_ECHOREP and the other reply's are 2042 * ICMP query's as well, but adding them here seems strange XXX 2043 */ 2044 if ((ofin.fin_flx & FI_ICMPERR) != 0) 2045 return NULL; 2046 2047 /* 2048 * perform a lookup of the ICMP packet in the state table 2049 */ 2050 icmp = (icmphdr_t *)((char *)oip + (IP_HL(oip) << 2)); 2051 hv = (pr = oip->ip_p); 2052 src.in4 = oip->ip_src; 2053 hv += src.in4.s_addr; 2054 dst.in4 = oip->ip_dst; 2055 hv += dst.in4.s_addr; 2056 hv += icmp->icmp_id; 2057 hv = DOUBLE_HASH(hv, ifs); 2058 2059 READ_ENTER(&ifs->ifs_ipf_state); 2060 for (isp = &ifs->ifs_ips_table[hv]; ((is = *isp) != NULL); ) { 2061 isp = &is->is_hnext; 2062 if ((is->is_p != pr) || (is->is_v != 4)) 2063 continue; 2064 if (is->is_pass & FR_NOICMPERR) 2065 continue; 2066 is = fr_matchsrcdst(&ofin, is, &src, &dst, 2067 NULL, FI_ICMPCMP); 2068 if (is != NULL) { 2069 if ((is->is_pass & FR_NOICMPERR) != 0) { 2070 RWLOCK_EXIT(&ifs->ifs_ipf_state); 2071 return NULL; 2072 } 2073 /* 2074 * i : the index of this packet (the icmp 2075 * unreachable) 2076 * oi : the index of the original packet found 2077 * in the icmp header (i.e. the packet 2078 * causing this icmp) 2079 * backward : original packet was backward 2080 * compared to the state 2081 */ 2082 backward = IP6_NEQ(&is->is_src, &src); 2083 fin->fin_rev = !backward; 2084 i = (!backward << 1) + fin->fin_out; 2085 oi = (backward << 1) + ofin.fin_out; 2086 if (is->is_icmppkts[i] > is->is_pkts[oi]) 2087 continue; 2088 ifs->ifs_ips_stats.iss_hits++; 2089 is->is_icmppkts[i]++; 2090 return is; 2091 } 2092 } 2093 RWLOCK_EXIT(&ifs->ifs_ipf_state); 2094 return NULL; 2095 case IPPROTO_TCP : 2096 case IPPROTO_UDP : 2097 break; 2098 default : 2099 return NULL; 2100 } 2101 2102 tcp = (tcphdr_t *)((char *)oip + (IP_HL(oip) << 2)); 2103 dport = tcp->th_dport; 2104 sport = tcp->th_sport; 2105 2106 hv = (pr = oip->ip_p); 2107 src.in4 = oip->ip_src; 2108 hv += src.in4.s_addr; 2109 dst.in4 = oip->ip_dst; 2110 hv += dst.in4.s_addr; 2111 hv += dport; 2112 hv += sport; 2113 hv = DOUBLE_HASH(hv, ifs); 2114 2115 READ_ENTER(&ifs->ifs_ipf_state); 2116 for (isp = &ifs->ifs_ips_table[hv]; ((is = *isp) != NULL); ) { 2117 isp = &is->is_hnext; 2118 /* 2119 * Only allow this icmp though if the 2120 * encapsulated packet was allowed through the 2121 * other way around. Note that the minimal amount 2122 * of info present does not allow for checking against 2123 * tcp internals such as seq and ack numbers. Only the 2124 * ports are known to be present and can be even if the 2125 * short flag is set. 2126 */ 2127 if ((is->is_p == pr) && (is->is_v == 4) && 2128 (is = fr_matchsrcdst(&ofin, is, &src, &dst, 2129 tcp, FI_ICMPCMP))) { 2130 /* 2131 * i : the index of this packet (the icmp unreachable) 2132 * oi : the index of the original packet found in the 2133 * icmp header (i.e. the packet causing this icmp) 2134 * backward : original packet was backward compared to 2135 * the state 2136 */ 2137 backward = IP6_NEQ(&is->is_src, &src); 2138 fin->fin_rev = !backward; 2139 i = (!backward << 1) + fin->fin_out; 2140 oi = (backward << 1) + ofin.fin_out; 2141 2142 if (((is->is_pass & FR_NOICMPERR) != 0) || 2143 (is->is_icmppkts[i] > is->is_pkts[oi])) 2144 break; 2145 ifs->ifs_ips_stats.iss_hits++; 2146 is->is_icmppkts[i]++; 2147 /* 2148 * we deliberately do not touch the timeouts 2149 * for the accompanying state table entry. 2150 * It remains to be seen if that is correct. XXX 2151 */ 2152 return is; 2153 } 2154 } 2155 RWLOCK_EXIT(&ifs->ifs_ipf_state); 2156 return NULL; 2157 } 2158 2159 2160 /* ------------------------------------------------------------------------ */ 2161 /* Function: fr_ipsmove */ 2162 /* Returns: Nil */ 2163 /* Parameters: is(I) - pointer to state table entry */ 2164 /* hv(I) - new hash value for state table entry */ 2165 /* Write Locks: ipf_state */ 2166 /* */ 2167 /* Move a state entry from one position in the hash table to another. */ 2168 /* ------------------------------------------------------------------------ */ 2169 static void fr_ipsmove(is, hv, ifs) 2170 ipstate_t *is; 2171 u_int hv; 2172 ipf_stack_t *ifs; 2173 { 2174 ipstate_t **isp; 2175 u_int hvm; 2176 2177 ASSERT(rw_read_locked(&ifs->ifs_ipf_state.ipf_lk) == 0); 2178 2179 hvm = is->is_hv; 2180 /* 2181 * Remove the hash from the old location... 2182 */ 2183 isp = is->is_phnext; 2184 if (is->is_hnext) 2185 is->is_hnext->is_phnext = isp; 2186 *isp = is->is_hnext; 2187 if (ifs->ifs_ips_table[hvm] == NULL) 2188 ifs->ifs_ips_stats.iss_inuse--; 2189 ifs->ifs_ips_stats.iss_bucketlen[hvm]--; 2190 2191 /* 2192 * ...and put the hash in the new one. 2193 */ 2194 hvm = DOUBLE_HASH(hv, ifs); 2195 is->is_hv = hvm; 2196 isp = &ifs->ifs_ips_table[hvm]; 2197 if (*isp) 2198 (*isp)->is_phnext = &is->is_hnext; 2199 else 2200 ifs->ifs_ips_stats.iss_inuse++; 2201 ifs->ifs_ips_stats.iss_bucketlen[hvm]++; 2202 is->is_phnext = isp; 2203 is->is_hnext = *isp; 2204 *isp = is; 2205 } 2206 2207 2208 /* ------------------------------------------------------------------------ */ 2209 /* Function: fr_stlookup */ 2210 /* Returns: ipstate_t* - NULL == no matching state found, */ 2211 /* else pointer to state information is returned */ 2212 /* Parameters: fin(I) - pointer to packet information */ 2213 /* tcp(I) - pointer to TCP/UDP header. */ 2214 /* */ 2215 /* Search the state table for a matching entry to the packet described by */ 2216 /* the contents of *fin. */ 2217 /* */ 2218 /* If we return NULL then no lock on ipf_state is held. */ 2219 /* If we return non-null then a read-lock on ipf_state is held. */ 2220 /* ------------------------------------------------------------------------ */ 2221 ipstate_t *fr_stlookup(fin, tcp, ifqp) 2222 fr_info_t *fin; 2223 tcphdr_t *tcp; 2224 ipftq_t **ifqp; 2225 { 2226 u_int hv, hvm, pr, v, tryagain; 2227 ipstate_t *is, **isp; 2228 u_short dport, sport; 2229 i6addr_t src, dst; 2230 struct icmp *ic; 2231 ipftq_t *ifq; 2232 int oow; 2233 ipf_stack_t *ifs = fin->fin_ifs; 2234 2235 is = NULL; 2236 ifq = NULL; 2237 tcp = fin->fin_dp; 2238 ic = (struct icmp *)tcp; 2239 hv = (pr = fin->fin_fi.fi_p); 2240 src = fin->fin_fi.fi_src; 2241 dst = fin->fin_fi.fi_dst; 2242 hv += src.in4.s_addr; 2243 hv += dst.in4.s_addr; 2244 2245 v = fin->fin_fi.fi_v; 2246 #ifdef USE_INET6 2247 if (v == 6) { 2248 hv += fin->fin_fi.fi_src.i6[1]; 2249 hv += fin->fin_fi.fi_src.i6[2]; 2250 hv += fin->fin_fi.fi_src.i6[3]; 2251 2252 if ((fin->fin_p == IPPROTO_ICMPV6) && 2253 IN6_IS_ADDR_MULTICAST(&fin->fin_fi.fi_dst.in6)) { 2254 hv -= dst.in4.s_addr; 2255 } else { 2256 hv += fin->fin_fi.fi_dst.i6[1]; 2257 hv += fin->fin_fi.fi_dst.i6[2]; 2258 hv += fin->fin_fi.fi_dst.i6[3]; 2259 } 2260 } 2261 #endif 2262 2263 /* 2264 * Search the hash table for matching packet header info. 2265 */ 2266 switch (pr) 2267 { 2268 #ifdef USE_INET6 2269 case IPPROTO_ICMPV6 : 2270 tryagain = 0; 2271 if (v == 6) { 2272 if ((ic->icmp_type == ICMP6_ECHO_REQUEST) || 2273 (ic->icmp_type == ICMP6_ECHO_REPLY)) { 2274 hv += ic->icmp_id; 2275 } 2276 } 2277 READ_ENTER(&ifs->ifs_ipf_state); 2278 icmp6again: 2279 hvm = DOUBLE_HASH(hv, ifs); 2280 for (isp = &ifs->ifs_ips_table[hvm]; ((is = *isp) != NULL); ) { 2281 isp = &is->is_hnext; 2282 if ((is->is_p != pr) || (is->is_v != v)) 2283 continue; 2284 is = fr_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP); 2285 if (is != NULL && 2286 fr_matchicmpqueryreply(v, &is->is_icmp, 2287 ic, fin->fin_rev)) { 2288 if (fin->fin_rev) 2289 ifq = &ifs->ifs_ips_icmpacktq; 2290 else 2291 ifq = &ifs->ifs_ips_icmptq; 2292 break; 2293 } 2294 } 2295 2296 if (is != NULL) { 2297 if ((tryagain != 0) && !(is->is_flags & SI_W_DADDR)) { 2298 hv += fin->fin_fi.fi_src.i6[0]; 2299 hv += fin->fin_fi.fi_src.i6[1]; 2300 hv += fin->fin_fi.fi_src.i6[2]; 2301 hv += fin->fin_fi.fi_src.i6[3]; 2302 fr_ipsmove(is, hv, ifs); 2303 MUTEX_DOWNGRADE(&ifs->ifs_ipf_state); 2304 } 2305 break; 2306 } 2307 RWLOCK_EXIT(&ifs->ifs_ipf_state); 2308 2309 /* 2310 * No matching icmp state entry. Perhaps this is a 2311 * response to another state entry. 2312 * 2313 * XXX With some ICMP6 packets, the "other" address is already 2314 * in the packet, after the ICMP6 header, and this could be 2315 * used in place of the multicast address. However, taking 2316 * advantage of this requires some significant code changes 2317 * to handle the specific types where that is the case. 2318 */ 2319 if ((ifs->ifs_ips_stats.iss_wild != 0) && (v == 6) && (tryagain == 0) && 2320 !IN6_IS_ADDR_MULTICAST(&fin->fin_fi.fi_src.in6)) { 2321 hv -= fin->fin_fi.fi_src.i6[0]; 2322 hv -= fin->fin_fi.fi_src.i6[1]; 2323 hv -= fin->fin_fi.fi_src.i6[2]; 2324 hv -= fin->fin_fi.fi_src.i6[3]; 2325 tryagain = 1; 2326 WRITE_ENTER(&ifs->ifs_ipf_state); 2327 goto icmp6again; 2328 } 2329 2330 is = fr_checkicmp6matchingstate(fin); 2331 if (is != NULL) 2332 return is; 2333 break; 2334 #endif 2335 2336 case IPPROTO_ICMP : 2337 if (v == 4) { 2338 hv += ic->icmp_id; 2339 } 2340 hv = DOUBLE_HASH(hv, ifs); 2341 READ_ENTER(&ifs->ifs_ipf_state); 2342 for (isp = &ifs->ifs_ips_table[hv]; ((is = *isp) != NULL); ) { 2343 isp = &is->is_hnext; 2344 if ((is->is_p != pr) || (is->is_v != v)) 2345 continue; 2346 is = fr_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP); 2347 if (is != NULL && 2348 fr_matchicmpqueryreply(v, &is->is_icmp, 2349 ic, fin->fin_rev)) { 2350 if (fin->fin_rev) 2351 ifq = &ifs->ifs_ips_icmpacktq; 2352 else 2353 ifq = &ifs->ifs_ips_icmptq; 2354 break; 2355 } 2356 } 2357 if (is == NULL) { 2358 RWLOCK_EXIT(&ifs->ifs_ipf_state); 2359 } 2360 break; 2361 2362 case IPPROTO_TCP : 2363 case IPPROTO_UDP : 2364 ifqp = NULL; 2365 sport = htons(fin->fin_data[0]); 2366 hv += sport; 2367 dport = htons(fin->fin_data[1]); 2368 hv += dport; 2369 oow = 0; 2370 tryagain = 0; 2371 READ_ENTER(&ifs->ifs_ipf_state); 2372 retry_tcpudp: 2373 hvm = DOUBLE_HASH(hv, ifs); 2374 for (isp = &ifs->ifs_ips_table[hvm]; ((is = *isp) != NULL); ) { 2375 isp = &is->is_hnext; 2376 if ((is->is_p != pr) || (is->is_v != v)) 2377 continue; 2378 fin->fin_flx &= ~FI_OOW; 2379 is = fr_matchsrcdst(fin, is, &src, &dst, tcp, FI_CMP); 2380 if (is != NULL) { 2381 if (pr == IPPROTO_TCP) { 2382 if (!fr_tcpstate(fin, tcp, is)) { 2383 oow |= fin->fin_flx & FI_OOW; 2384 continue; 2385 } 2386 } 2387 break; 2388 } 2389 } 2390 if (is != NULL) { 2391 if (tryagain && 2392 !(is->is_flags & (SI_CLONE|SI_WILDP|SI_WILDA))) { 2393 hv += dport; 2394 hv += sport; 2395 fr_ipsmove(is, hv, ifs); 2396 MUTEX_DOWNGRADE(&ifs->ifs_ipf_state); 2397 } 2398 break; 2399 } 2400 RWLOCK_EXIT(&ifs->ifs_ipf_state); 2401 2402 if (!tryagain && ifs->ifs_ips_stats.iss_wild) { 2403 hv -= dport; 2404 hv -= sport; 2405 tryagain = 1; 2406 WRITE_ENTER(&ifs->ifs_ipf_state); 2407 goto retry_tcpudp; 2408 } 2409 fin->fin_flx |= oow; 2410 break; 2411 2412 #if 0 2413 case IPPROTO_GRE : 2414 gre = fin->fin_dp; 2415 if (GRE_REV(gre->gr_flags) == 1) { 2416 hv += gre->gr_call; 2417 } 2418 /* FALLTHROUGH */ 2419 #endif 2420 default : 2421 ifqp = NULL; 2422 hvm = DOUBLE_HASH(hv, ifs); 2423 READ_ENTER(&ifs->ifs_ipf_state); 2424 for (isp = &ifs->ifs_ips_table[hvm]; ((is = *isp) != NULL); ) { 2425 isp = &is->is_hnext; 2426 if ((is->is_p != pr) || (is->is_v != v)) 2427 continue; 2428 is = fr_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP); 2429 if (is != NULL) { 2430 ifq = &ifs->ifs_ips_iptq; 2431 break; 2432 } 2433 } 2434 if (is == NULL) { 2435 RWLOCK_EXIT(&ifs->ifs_ipf_state); 2436 } 2437 break; 2438 } 2439 2440 if ((is != NULL) && ((is->is_sti.tqe_flags & TQE_RULEBASED) != 0) && 2441 (is->is_tqehead[fin->fin_rev] != NULL)) 2442 ifq = is->is_tqehead[fin->fin_rev]; 2443 if (ifq != NULL && ifqp != NULL) 2444 *ifqp = ifq; 2445 return is; 2446 } 2447 2448 2449 /* ------------------------------------------------------------------------ */ 2450 /* Function: fr_updatestate */ 2451 /* Returns: Nil */ 2452 /* Parameters: fin(I) - pointer to packet information */ 2453 /* is(I) - pointer to state table entry */ 2454 /* Read Locks: ipf_state */ 2455 /* */ 2456 /* Updates packet and byte counters for a newly received packet. Seeds the */ 2457 /* fragment cache with a new entry as required. */ 2458 /* ------------------------------------------------------------------------ */ 2459 void fr_updatestate(fin, is, ifq) 2460 fr_info_t *fin; 2461 ipstate_t *is; 2462 ipftq_t *ifq; 2463 { 2464 ipftqent_t *tqe; 2465 int i, pass; 2466 ipf_stack_t *ifs = fin->fin_ifs; 2467 2468 i = (fin->fin_rev << 1) + fin->fin_out; 2469 2470 /* 2471 * For TCP packets, ifq == NULL. For all others, check if this new 2472 * queue is different to the last one it was on and move it if so. 2473 */ 2474 tqe = &is->is_sti; 2475 MUTEX_ENTER(&is->is_lock); 2476 if ((tqe->tqe_flags & TQE_RULEBASED) != 0) 2477 ifq = is->is_tqehead[fin->fin_rev]; 2478 2479 if (ifq != NULL) 2480 fr_movequeue(tqe, tqe->tqe_ifq, ifq, ifs); 2481 2482 is->is_pkts[i]++; 2483 is->is_bytes[i] += fin->fin_plen; 2484 MUTEX_EXIT(&is->is_lock); 2485 2486 #ifdef IPFILTER_SYNC 2487 if (is->is_flags & IS_STATESYNC) 2488 ipfsync_update(SMC_STATE, fin, is->is_sync); 2489 #endif 2490 2491 ATOMIC_INCL(ifs->ifs_ips_stats.iss_hits); 2492 2493 fin->fin_fr = is->is_rule; 2494 2495 /* 2496 * If this packet is a fragment and the rule says to track fragments, 2497 * then create a new fragment cache entry. 2498 */ 2499 pass = is->is_pass; 2500 if ((fin->fin_flx & FI_FRAG) && FR_ISPASS(pass)) 2501 (void) fr_newfrag(fin, pass ^ FR_KEEPSTATE); 2502 } 2503 2504 2505 /* ------------------------------------------------------------------------ */ 2506 /* Function: fr_checkstate */ 2507 /* Returns: frentry_t* - NULL == search failed, */ 2508 /* else pointer to rule for matching state */ 2509 /* Parameters: ifp(I) - pointer to interface */ 2510 /* passp(I) - pointer to filtering result flags */ 2511 /* */ 2512 /* Check if a packet is associated with an entry in the state table. */ 2513 /* ------------------------------------------------------------------------ */ 2514 frentry_t *fr_checkstate(fin, passp) 2515 fr_info_t *fin; 2516 u_32_t *passp; 2517 { 2518 ipstate_t *is; 2519 frentry_t *fr; 2520 tcphdr_t *tcp; 2521 ipftq_t *ifq; 2522 u_int pass; 2523 ipf_stack_t *ifs = fin->fin_ifs; 2524 2525 if (ifs->ifs_fr_state_lock || (ifs->ifs_ips_list == NULL) || 2526 (fin->fin_flx & (FI_SHORT|FI_STATE|FI_FRAGBODY|FI_BAD))) 2527 return NULL; 2528 2529 is = NULL; 2530 if ((fin->fin_flx & FI_TCPUDP) || 2531 (fin->fin_fi.fi_p == IPPROTO_ICMP) 2532 #ifdef USE_INET6 2533 || (fin->fin_fi.fi_p == IPPROTO_ICMPV6) 2534 #endif 2535 ) 2536 tcp = fin->fin_dp; 2537 else 2538 tcp = NULL; 2539 2540 /* 2541 * Search the hash table for matching packet header info. 2542 */ 2543 ifq = NULL; 2544 is = fin->fin_state; 2545 if (is == NULL) 2546 is = fr_stlookup(fin, tcp, &ifq); 2547 switch (fin->fin_p) 2548 { 2549 #ifdef USE_INET6 2550 case IPPROTO_ICMPV6 : 2551 if (is != NULL) 2552 break; 2553 if (fin->fin_v == 6) { 2554 is = fr_checkicmp6matchingstate(fin); 2555 if (is != NULL) 2556 goto matched; 2557 } 2558 break; 2559 #endif 2560 case IPPROTO_ICMP : 2561 if (is != NULL) 2562 break; 2563 /* 2564 * No matching icmp state entry. Perhaps this is a 2565 * response to another state entry. 2566 */ 2567 is = fr_checkicmpmatchingstate(fin); 2568 if (is != NULL) 2569 goto matched; 2570 break; 2571 case IPPROTO_TCP : 2572 if (is == NULL) 2573 break; 2574 2575 if (is->is_pass & FR_NEWISN) { 2576 if (fin->fin_out == 0) 2577 fr_fixinisn(fin, is); 2578 else if (fin->fin_out == 1) 2579 fr_fixoutisn(fin, is); 2580 } 2581 break; 2582 default : 2583 if (fin->fin_rev) 2584 ifq = &ifs->ifs_ips_udpacktq; 2585 else 2586 ifq = &ifs->ifs_ips_udptq; 2587 break; 2588 } 2589 if (is == NULL) { 2590 ATOMIC_INCL(ifs->ifs_ips_stats.iss_miss); 2591 return NULL; 2592 } 2593 2594 matched: 2595 fr = is->is_rule; 2596 if (fr != NULL) { 2597 if ((fin->fin_out == 0) && (fr->fr_nattag.ipt_num[0] != 0)) { 2598 if (fin->fin_nattag == NULL) 2599 return NULL; 2600 if (fr_matchtag(&fr->fr_nattag, fin->fin_nattag) != 0) 2601 return NULL; 2602 } 2603 (void) strncpy(fin->fin_group, fr->fr_group, FR_GROUPLEN); 2604 fin->fin_icode = fr->fr_icode; 2605 } 2606 2607 fin->fin_rule = is->is_rulen; 2608 pass = is->is_pass; 2609 fr_updatestate(fin, is, ifq); 2610 if (fin->fin_out == 1) 2611 fin->fin_nat = is->is_nat[fin->fin_rev]; 2612 2613 fin->fin_state = is; 2614 is->is_touched = ifs->ifs_fr_ticks; 2615 MUTEX_ENTER(&is->is_lock); 2616 is->is_ref++; 2617 MUTEX_EXIT(&is->is_lock); 2618 RWLOCK_EXIT(&ifs->ifs_ipf_state); 2619 fin->fin_flx |= FI_STATE; 2620 if ((pass & FR_LOGFIRST) != 0) 2621 pass &= ~(FR_LOGFIRST|FR_LOG); 2622 *passp = pass; 2623 return fr; 2624 } 2625 2626 2627 /* ------------------------------------------------------------------------ */ 2628 /* Function: fr_fixoutisn */ 2629 /* Returns: Nil */ 2630 /* Parameters: fin(I) - pointer to packet information */ 2631 /* is(I) - pointer to master state structure */ 2632 /* */ 2633 /* Called only for outbound packets, adjusts the sequence number and the */ 2634 /* TCP checksum to match that change. */ 2635 /* ------------------------------------------------------------------------ */ 2636 static void fr_fixoutisn(fin, is) 2637 fr_info_t *fin; 2638 ipstate_t *is; 2639 { 2640 tcphdr_t *tcp; 2641 int rev; 2642 u_32_t seq; 2643 2644 tcp = fin->fin_dp; 2645 rev = fin->fin_rev; 2646 if ((is->is_flags & IS_ISNSYN) != 0) { 2647 if (rev == 0) { 2648 seq = ntohl(tcp->th_seq); 2649 seq += is->is_isninc[0]; 2650 tcp->th_seq = htonl(seq); 2651 fix_outcksum(&tcp->th_sum, is->is_sumd[0]); 2652 } 2653 } 2654 if ((is->is_flags & IS_ISNACK) != 0) { 2655 if (rev == 1) { 2656 seq = ntohl(tcp->th_seq); 2657 seq += is->is_isninc[1]; 2658 tcp->th_seq = htonl(seq); 2659 fix_outcksum(&tcp->th_sum, is->is_sumd[1]); 2660 } 2661 } 2662 } 2663 2664 2665 /* ------------------------------------------------------------------------ */ 2666 /* Function: fr_fixinisn */ 2667 /* Returns: Nil */ 2668 /* Parameters: fin(I) - pointer to packet information */ 2669 /* is(I) - pointer to master state structure */ 2670 /* */ 2671 /* Called only for inbound packets, adjusts the acknowledge number and the */ 2672 /* TCP checksum to match that change. */ 2673 /* ------------------------------------------------------------------------ */ 2674 static void fr_fixinisn(fin, is) 2675 fr_info_t *fin; 2676 ipstate_t *is; 2677 { 2678 tcphdr_t *tcp; 2679 int rev; 2680 u_32_t ack; 2681 2682 tcp = fin->fin_dp; 2683 rev = fin->fin_rev; 2684 if ((is->is_flags & IS_ISNSYN) != 0) { 2685 if (rev == 1) { 2686 ack = ntohl(tcp->th_ack); 2687 ack -= is->is_isninc[0]; 2688 tcp->th_ack = htonl(ack); 2689 fix_incksum(&tcp->th_sum, is->is_sumd[0]); 2690 } 2691 } 2692 if ((is->is_flags & IS_ISNACK) != 0) { 2693 if (rev == 0) { 2694 ack = ntohl(tcp->th_ack); 2695 ack -= is->is_isninc[1]; 2696 tcp->th_ack = htonl(ack); 2697 fix_incksum(&tcp->th_sum, is->is_sumd[1]); 2698 } 2699 } 2700 } 2701 2702 2703 /* ------------------------------------------------------------------------ */ 2704 /* Function: fr_statesync */ 2705 /* Returns: Nil */ 2706 /* Parameters: action(I) - type of synchronisation to do */ 2707 /* v(I) - IP version being sync'd (v4 or v6) */ 2708 /* ifp(I) - interface identifier associated with action */ 2709 /* name(I) - name associated with ifp parameter */ 2710 /* */ 2711 /* Walk through all state entries and if an interface pointer match is */ 2712 /* found then look it up again, based on its name in case the pointer has */ 2713 /* changed since last time. */ 2714 /* */ 2715 /* If ifp is passed in as being non-null then we are only doing updates for */ 2716 /* existing, matching, uses of it. */ 2717 /* ------------------------------------------------------------------------ */ 2718 void fr_statesync(action, v, ifp, name, ifs) 2719 int action, v; 2720 void *ifp; 2721 char *name; 2722 ipf_stack_t *ifs; 2723 { 2724 ipstate_t *is; 2725 int i; 2726 2727 if (ifs->ifs_fr_running <= 0) 2728 return; 2729 2730 WRITE_ENTER(&ifs->ifs_ipf_state); 2731 2732 if (ifs->ifs_fr_running <= 0) { 2733 RWLOCK_EXIT(&ifs->ifs_ipf_state); 2734 return; 2735 } 2736 2737 switch (action) 2738 { 2739 case IPFSYNC_RESYNC : 2740 for (is = ifs->ifs_ips_list; is; is = is->is_next) { 2741 if (v != 0 && is->is_v != v) 2742 continue; 2743 /* 2744 * Look up all the interface names in the state entry. 2745 */ 2746 for (i = 0; i < 4; i++) { 2747 is->is_ifp[i] = fr_resolvenic(is->is_ifname[i], 2748 is->is_v, ifs); 2749 } 2750 } 2751 break; 2752 case IPFSYNC_NEWIFP : 2753 for (is = ifs->ifs_ips_list; is; is = is->is_next) { 2754 if (v != 0 && is->is_v != v) 2755 continue; 2756 /* 2757 * Look up all the interface names in the state entry. 2758 */ 2759 for (i = 0; i < 4; i++) { 2760 if (!strncmp(is->is_ifname[i], name, 2761 sizeof(is->is_ifname[i]))) 2762 is->is_ifp[i] = ifp; 2763 } 2764 } 2765 break; 2766 case IPFSYNC_OLDIFP : 2767 for (is = ifs->ifs_ips_list; is; is = is->is_next) { 2768 if (v != 0 && is->is_v != v) 2769 continue; 2770 /* 2771 * Look up all the interface names in the state entry. 2772 */ 2773 for (i = 0; i < 4; i++) { 2774 if (is->is_ifp[i] == ifp) 2775 is->is_ifp[i] = (void *)-1; 2776 } 2777 } 2778 break; 2779 } 2780 RWLOCK_EXIT(&ifs->ifs_ipf_state); 2781 } 2782 2783 2784 /* ------------------------------------------------------------------------ */ 2785 /* Function: fr_delstate */ 2786 /* Returns: Nil */ 2787 /* Parameters: is(I) - pointer to state structure to delete */ 2788 /* why(I) - if not 0, log reason why it was deleted */ 2789 /* Write Locks: ipf_state/ipf_global */ 2790 /* */ 2791 /* Deletes a state entry from the enumerated list as well as the hash table */ 2792 /* and timeout queue lists. Make adjustments to hash table statistics and */ 2793 /* global counters as required. */ 2794 /* ------------------------------------------------------------------------ */ 2795 static void fr_delstate(is, why, ifs) 2796 ipstate_t *is; 2797 int why; 2798 ipf_stack_t *ifs; 2799 { 2800 2801 ASSERT(rw_write_held(&ifs->ifs_ipf_global.ipf_lk) == 0 || 2802 rw_write_held(&ifs->ifs_ipf_state.ipf_lk) == 0); 2803 2804 /* 2805 * Since we want to delete this, remove it from the state table, 2806 * where it can be found & used, first. 2807 */ 2808 if (is->is_pnext != NULL) { 2809 *is->is_pnext = is->is_next; 2810 2811 if (is->is_next != NULL) 2812 is->is_next->is_pnext = is->is_pnext; 2813 2814 is->is_pnext = NULL; 2815 is->is_next = NULL; 2816 } 2817 2818 if (is->is_phnext != NULL) { 2819 *is->is_phnext = is->is_hnext; 2820 if (is->is_hnext != NULL) 2821 is->is_hnext->is_phnext = is->is_phnext; 2822 if (ifs->ifs_ips_table[is->is_hv] == NULL) 2823 ifs->ifs_ips_stats.iss_inuse--; 2824 ifs->ifs_ips_stats.iss_bucketlen[is->is_hv]--; 2825 2826 is->is_phnext = NULL; 2827 is->is_hnext = NULL; 2828 } 2829 2830 /* 2831 * Because ifs->ifs_ips_stats.iss_wild is a count of entries in the state 2832 * table that have wildcard flags set, only decerement it once 2833 * and do it here. 2834 */ 2835 if (is->is_flags & (SI_WILDP|SI_WILDA)) { 2836 if (!(is->is_flags & SI_CLONED)) { 2837 ATOMIC_DECL(ifs->ifs_ips_stats.iss_wild); 2838 } 2839 is->is_flags &= ~(SI_WILDP|SI_WILDA); 2840 } 2841 2842 /* 2843 * Next, remove it from the timeout queue it is in. 2844 */ 2845 fr_deletequeueentry(&is->is_sti); 2846 2847 is->is_me = NULL; 2848 2849 /* 2850 * If it is still in use by something else, do not go any further, 2851 * but note that at this point it is now an orphan. 2852 */ 2853 is->is_ref--; 2854 if (is->is_ref > 0) 2855 return; 2856 2857 if (is->is_tqehead[0] != NULL) { 2858 if (fr_deletetimeoutqueue(is->is_tqehead[0]) == 0) 2859 fr_freetimeoutqueue(is->is_tqehead[0], ifs); 2860 } 2861 if (is->is_tqehead[1] != NULL) { 2862 if (fr_deletetimeoutqueue(is->is_tqehead[1]) == 0) 2863 fr_freetimeoutqueue(is->is_tqehead[1], ifs); 2864 } 2865 2866 #ifdef IPFILTER_SYNC 2867 if (is->is_sync) 2868 ipfsync_del(is->is_sync); 2869 #endif 2870 #ifdef IPFILTER_SCAN 2871 (void) ipsc_detachis(is); 2872 #endif 2873 2874 if (ifs->ifs_ipstate_logging != 0 && why != 0) 2875 ipstate_log(is, why, ifs); 2876 2877 if (is->is_rule != NULL) { 2878 is->is_rule->fr_statecnt--; 2879 (void)fr_derefrule(&is->is_rule, ifs); 2880 } 2881 2882 MUTEX_DESTROY(&is->is_lock); 2883 KFREE(is); 2884 ifs->ifs_ips_num--; 2885 } 2886 2887 2888 /* ------------------------------------------------------------------------ */ 2889 /* Function: fr_timeoutstate */ 2890 /* Returns: Nil */ 2891 /* Parameters: Nil */ 2892 /* */ 2893 /* Slowly expire held state for thingslike UDP and ICMP. The algorithm */ 2894 /* used here is to keep the queue sorted with the oldest things at the top */ 2895 /* and the youngest at the bottom. So if the top one doesn't need to be */ 2896 /* expired then neither will any under it. */ 2897 /* ------------------------------------------------------------------------ */ 2898 void fr_timeoutstate(ifs) 2899 ipf_stack_t *ifs; 2900 { 2901 ipftq_t *ifq, *ifqnext; 2902 ipftqent_t *tqe, *tqn; 2903 ipstate_t *is; 2904 SPL_INT(s); 2905 2906 SPL_NET(s); 2907 WRITE_ENTER(&ifs->ifs_ipf_state); 2908 for (ifq = ifs->ifs_ips_tqtqb; ifq != NULL; ifq = ifq->ifq_next) 2909 for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) { 2910 if (tqe->tqe_die > ifs->ifs_fr_ticks) 2911 break; 2912 tqn = tqe->tqe_next; 2913 is = tqe->tqe_parent; 2914 fr_delstate(is, ISL_EXPIRE, ifs); 2915 } 2916 2917 for (ifq = ifs->ifs_ips_utqe; ifq != NULL; ifq = ifqnext) { 2918 ifqnext = ifq->ifq_next; 2919 2920 for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) { 2921 if (tqe->tqe_die > ifs->ifs_fr_ticks) 2922 break; 2923 tqn = tqe->tqe_next; 2924 is = tqe->tqe_parent; 2925 fr_delstate(is, ISL_EXPIRE, ifs); 2926 } 2927 } 2928 2929 for (ifq = ifs->ifs_ips_utqe; ifq != NULL; ifq = ifqnext) { 2930 ifqnext = ifq->ifq_next; 2931 2932 if (((ifq->ifq_flags & IFQF_DELETE) != 0) && 2933 (ifq->ifq_ref == 0)) { 2934 fr_freetimeoutqueue(ifq, ifs); 2935 } 2936 } 2937 2938 if (ifs->ifs_fr_state_doflush) { 2939 (void) fr_state_flush(2, 0, ifs); 2940 ifs->ifs_fr_state_doflush = 0; 2941 } 2942 RWLOCK_EXIT(&ifs->ifs_ipf_state); 2943 SPL_X(s); 2944 } 2945 2946 2947 /* ------------------------------------------------------------------------ */ 2948 /* Function: fr_state_flush */ 2949 /* Returns: int - 0 == success, -1 == failure */ 2950 /* Parameters: Nil */ 2951 /* Write Locks: ipf_state */ 2952 /* */ 2953 /* Flush state tables. Three actions currently defined: */ 2954 /* which == 0 : flush all state table entries */ 2955 /* which == 1 : flush TCP connections which have started to close but are */ 2956 /* stuck for some reason. */ 2957 /* which == 2 : flush TCP connections which have been idle for a long time, */ 2958 /* starting at > 4 days idle and working back in successive half-*/ 2959 /* days to at most 12 hours old. If this fails to free enough */ 2960 /* slots then work backwards in half hour slots to 30 minutes. */ 2961 /* If that too fails, then work backwards in 30 second intervals */ 2962 /* for the last 30 minutes to at worst 30 seconds idle. */ 2963 /* ------------------------------------------------------------------------ */ 2964 static int fr_state_flush(which, proto, ifs) 2965 int which, proto; 2966 ipf_stack_t *ifs; 2967 { 2968 ipftq_t *ifq, *ifqnext; 2969 ipftqent_t *tqe, *tqn; 2970 ipstate_t *is, **isp; 2971 int delete, removed; 2972 long try, maxtick; 2973 u_long interval; 2974 SPL_INT(s); 2975 2976 removed = 0; 2977 2978 SPL_NET(s); 2979 for (isp = &ifs->ifs_ips_list; ((is = *isp) != NULL); ) { 2980 delete = 0; 2981 2982 if ((proto != 0) && (is->is_v != proto)) { 2983 isp = &is->is_next; 2984 continue; 2985 } 2986 2987 switch (which) 2988 { 2989 case 0 : 2990 delete = 1; 2991 break; 2992 case 1 : 2993 case 2 : 2994 if (is->is_p != IPPROTO_TCP) 2995 break; 2996 if ((is->is_state[0] != IPF_TCPS_ESTABLISHED) || 2997 (is->is_state[1] != IPF_TCPS_ESTABLISHED)) 2998 delete = 1; 2999 break; 3000 } 3001 3002 if (delete) { 3003 if (is->is_p == IPPROTO_TCP) 3004 ifs->ifs_ips_stats.iss_fin++; 3005 else 3006 ifs->ifs_ips_stats.iss_expire++; 3007 fr_delstate(is, ISL_FLUSH, ifs); 3008 removed++; 3009 } else 3010 isp = &is->is_next; 3011 } 3012 3013 if (which != 2) { 3014 SPL_X(s); 3015 return removed; 3016 } 3017 3018 /* 3019 * Asked to remove inactive entries because the table is full, try 3020 * again, 3 times, if first attempt failed with a different criteria 3021 * each time. The order tried in must be in decreasing age. 3022 * Another alternative is to implement random drop and drop N entries 3023 * at random until N have been freed up. 3024 */ 3025 if (ifs->ifs_fr_ticks - ifs->ifs_ips_last_force_flush < IPF_TTLVAL(5)) 3026 goto force_flush_skipped; 3027 ifs->ifs_ips_last_force_flush = ifs->ifs_fr_ticks; 3028 3029 if (ifs->ifs_fr_ticks > IPF_TTLVAL(43200)) 3030 interval = IPF_TTLVAL(43200); 3031 else if (ifs->ifs_fr_ticks > IPF_TTLVAL(1800)) 3032 interval = IPF_TTLVAL(1800); 3033 else if (ifs->ifs_fr_ticks > IPF_TTLVAL(30)) 3034 interval = IPF_TTLVAL(30); 3035 else 3036 interval = IPF_TTLVAL(10); 3037 try = ifs->ifs_fr_ticks - (ifs->ifs_fr_ticks - interval); 3038 if (try < 0) 3039 goto force_flush_skipped; 3040 3041 while (removed == 0) { 3042 maxtick = ifs->ifs_fr_ticks - interval; 3043 if (maxtick < 0) 3044 break; 3045 3046 while (try < maxtick) { 3047 for (ifq = ifs->ifs_ips_tqtqb; ifq != NULL; 3048 ifq = ifq->ifq_next) { 3049 for (tqn = ifq->ifq_head; 3050 ((tqe = tqn) != NULL); ) { 3051 if (tqe->tqe_die > try) 3052 break; 3053 tqn = tqe->tqe_next; 3054 is = tqe->tqe_parent; 3055 fr_delstate(is, ISL_EXPIRE, ifs); 3056 removed++; 3057 } 3058 } 3059 3060 for (ifq = ifs->ifs_ips_utqe; ifq != NULL; ifq = ifqnext) { 3061 ifqnext = ifq->ifq_next; 3062 3063 for (tqn = ifq->ifq_head; 3064 ((tqe = tqn) != NULL); ) { 3065 if (tqe->tqe_die > try) 3066 break; 3067 tqn = tqe->tqe_next; 3068 is = tqe->tqe_parent; 3069 fr_delstate(is, ISL_EXPIRE, ifs); 3070 removed++; 3071 } 3072 } 3073 if (try + interval > maxtick) 3074 break; 3075 try += interval; 3076 } 3077 3078 if (removed == 0) { 3079 if (interval == IPF_TTLVAL(43200)) { 3080 interval = IPF_TTLVAL(1800); 3081 } else if (interval == IPF_TTLVAL(1800)) { 3082 interval = IPF_TTLVAL(30); 3083 } else if (interval == IPF_TTLVAL(30)) { 3084 interval = IPF_TTLVAL(10); 3085 } else { 3086 break; 3087 } 3088 } 3089 } 3090 force_flush_skipped: 3091 SPL_X(s); 3092 return removed; 3093 } 3094 3095 3096 3097 /* ------------------------------------------------------------------------ */ 3098 /* Function: fr_tcp_age */ 3099 /* Returns: int - 1 == state transition made, 0 == no change (rejected) */ 3100 /* Parameters: tq(I) - pointer to timeout queue information */ 3101 /* fin(I) - pointer to packet information */ 3102 /* tqtab(I) - TCP timeout queue table this is in */ 3103 /* flags(I) - flags from state/NAT entry */ 3104 /* */ 3105 /* Rewritten by Arjan de Vet <Arjan.deVet@adv.iae.nl>, 2000-07-29: */ 3106 /* */ 3107 /* - (try to) base state transitions on real evidence only, */ 3108 /* i.e. packets that are sent and have been received by ipfilter; */ 3109 /* diagram 18.12 of TCP/IP volume 1 by W. Richard Stevens was used. */ 3110 /* */ 3111 /* - deal with half-closed connections correctly; */ 3112 /* */ 3113 /* - store the state of the source in state[0] such that ipfstat */ 3114 /* displays the state as source/dest instead of dest/source; the calls */ 3115 /* to fr_tcp_age have been changed accordingly. */ 3116 /* */ 3117 /* Internal Parameters: */ 3118 /* */ 3119 /* state[0] = state of source (host that initiated connection) */ 3120 /* state[1] = state of dest (host that accepted the connection) */ 3121 /* */ 3122 /* dir == 0 : a packet from source to dest */ 3123 /* dir == 1 : a packet from dest to source */ 3124 /* */ 3125 /* Locking: it is assumed that the parent of the tqe structure is locked. */ 3126 /* ------------------------------------------------------------------------ */ 3127 int fr_tcp_age(tqe, fin, tqtab, flags) 3128 ipftqent_t *tqe; 3129 fr_info_t *fin; 3130 ipftq_t *tqtab; 3131 int flags; 3132 { 3133 int dlen, ostate, nstate, rval, dir; 3134 u_char tcpflags; 3135 tcphdr_t *tcp; 3136 ipf_stack_t *ifs = fin->fin_ifs; 3137 3138 tcp = fin->fin_dp; 3139 3140 rval = 0; 3141 dir = fin->fin_rev; 3142 tcpflags = tcp->th_flags; 3143 dlen = fin->fin_dlen - (TCP_OFF(tcp) << 2); 3144 3145 if (tcpflags & TH_RST) { 3146 if (!(tcpflags & TH_PUSH) && !dlen) 3147 nstate = IPF_TCPS_CLOSED; 3148 else 3149 nstate = IPF_TCPS_CLOSE_WAIT; 3150 rval = 1; 3151 } else { 3152 ostate = tqe->tqe_state[1 - dir]; 3153 nstate = tqe->tqe_state[dir]; 3154 3155 switch (nstate) 3156 { 3157 case IPF_TCPS_CLOSED: /* 0 */ 3158 if ((tcpflags & TH_OPENING) == TH_OPENING) { 3159 /* 3160 * 'dir' received an S and sends SA in 3161 * response, CLOSED -> SYN_RECEIVED 3162 */ 3163 nstate = IPF_TCPS_SYN_RECEIVED; 3164 rval = 1; 3165 } else if ((tcpflags & TH_OPENING) == TH_SYN) { 3166 /* 'dir' sent S, CLOSED -> SYN_SENT */ 3167 nstate = IPF_TCPS_SYN_SENT; 3168 rval = 1; 3169 } 3170 /* 3171 * the next piece of code makes it possible to get 3172 * already established connections into the state table 3173 * after a restart or reload of the filter rules; this 3174 * does not work when a strict 'flags S keep state' is 3175 * used for tcp connections of course 3176 */ 3177 if (((flags & IS_TCPFSM) == 0) && 3178 ((tcpflags & TH_ACKMASK) == TH_ACK)) { 3179 /* 3180 * we saw an A, guess 'dir' is in ESTABLISHED 3181 * mode 3182 */ 3183 switch (ostate) 3184 { 3185 case IPF_TCPS_CLOSED : 3186 case IPF_TCPS_SYN_RECEIVED : 3187 nstate = IPF_TCPS_HALF_ESTAB; 3188 rval = 1; 3189 break; 3190 case IPF_TCPS_HALF_ESTAB : 3191 case IPF_TCPS_ESTABLISHED : 3192 nstate = IPF_TCPS_ESTABLISHED; 3193 rval = 1; 3194 break; 3195 default : 3196 break; 3197 } 3198 } 3199 /* 3200 * TODO: besides regular ACK packets we can have other 3201 * packets as well; it is yet to be determined how we 3202 * should initialize the states in those cases 3203 */ 3204 break; 3205 3206 case IPF_TCPS_LISTEN: /* 1 */ 3207 /* NOT USED */ 3208 break; 3209 3210 case IPF_TCPS_SYN_SENT: /* 2 */ 3211 if ((tcpflags & ~(TH_ECN|TH_CWR)) == TH_SYN) { 3212 /* 3213 * A retransmitted SYN packet. We do not reset 3214 * the timeout here to fr_tcptimeout because a 3215 * connection connect timeout does not renew 3216 * after every packet that is sent. We need to 3217 * set rval so as to indicate the packet has 3218 * passed the check for its flags being valid 3219 * in the TCP FSM. Setting rval to 2 has the 3220 * result of not resetting the timeout. 3221 */ 3222 rval = 2; 3223 } else if ((tcpflags & (TH_SYN|TH_FIN|TH_ACK)) == 3224 TH_ACK) { 3225 /* 3226 * we see an A from 'dir' which is in SYN_SENT 3227 * state: 'dir' sent an A in response to an SA 3228 * which it received, SYN_SENT -> ESTABLISHED 3229 */ 3230 nstate = IPF_TCPS_ESTABLISHED; 3231 rval = 1; 3232 } else if (tcpflags & TH_FIN) { 3233 /* 3234 * we see an F from 'dir' which is in SYN_SENT 3235 * state and wants to close its side of the 3236 * connection; SYN_SENT -> FIN_WAIT_1 3237 */ 3238 nstate = IPF_TCPS_FIN_WAIT_1; 3239 rval = 1; 3240 } else if ((tcpflags & TH_OPENING) == TH_OPENING) { 3241 /* 3242 * we see an SA from 'dir' which is already in 3243 * SYN_SENT state, this means we have a 3244 * simultaneous open; SYN_SENT -> SYN_RECEIVED 3245 */ 3246 nstate = IPF_TCPS_SYN_RECEIVED; 3247 rval = 1; 3248 } 3249 break; 3250 3251 case IPF_TCPS_SYN_RECEIVED: /* 3 */ 3252 if ((tcpflags & (TH_SYN|TH_FIN|TH_ACK)) == TH_ACK) { 3253 /* 3254 * we see an A from 'dir' which was in 3255 * SYN_RECEIVED state so it must now be in 3256 * established state, SYN_RECEIVED -> 3257 * ESTABLISHED 3258 */ 3259 nstate = IPF_TCPS_ESTABLISHED; 3260 rval = 1; 3261 } else if ((tcpflags & ~(TH_ECN|TH_CWR)) == 3262 TH_OPENING) { 3263 /* 3264 * We see an SA from 'dir' which is already in 3265 * SYN_RECEIVED state. 3266 */ 3267 rval = 2; 3268 } else if (tcpflags & TH_FIN) { 3269 /* 3270 * we see an F from 'dir' which is in 3271 * SYN_RECEIVED state and wants to close its 3272 * side of the connection; SYN_RECEIVED -> 3273 * FIN_WAIT_1 3274 */ 3275 nstate = IPF_TCPS_FIN_WAIT_1; 3276 rval = 1; 3277 } 3278 break; 3279 3280 case IPF_TCPS_HALF_ESTAB: /* 4 */ 3281 if (ostate >= IPF_TCPS_HALF_ESTAB) { 3282 if ((tcpflags & TH_ACKMASK) == TH_ACK) { 3283 nstate = IPF_TCPS_ESTABLISHED; 3284 rval = 1; 3285 } 3286 } 3287 3288 break; 3289 3290 case IPF_TCPS_ESTABLISHED: /* 5 */ 3291 rval = 1; 3292 if (tcpflags & TH_FIN) { 3293 /* 3294 * 'dir' closed its side of the connection; 3295 * this gives us a half-closed connection; 3296 * ESTABLISHED -> FIN_WAIT_1 3297 */ 3298 nstate = IPF_TCPS_FIN_WAIT_1; 3299 } else if (tcpflags & TH_ACK) { 3300 /* 3301 * an ACK, should we exclude other flags here? 3302 */ 3303 if (ostate == IPF_TCPS_FIN_WAIT_1) { 3304 /* 3305 * We know the other side did an active 3306 * close, so we are ACKing the recvd 3307 * FIN packet (does the window matching 3308 * code guarantee this?) and go into 3309 * CLOSE_WAIT state; this gives us a 3310 * half-closed connection 3311 */ 3312 nstate = IPF_TCPS_CLOSE_WAIT; 3313 } else if (ostate < IPF_TCPS_CLOSE_WAIT) { 3314 /* 3315 * still a fully established 3316 * connection reset timeout 3317 */ 3318 nstate = IPF_TCPS_ESTABLISHED; 3319 } 3320 } 3321 break; 3322 3323 case IPF_TCPS_CLOSE_WAIT: /* 6 */ 3324 rval = 1; 3325 if (tcpflags & TH_FIN) { 3326 /* 3327 * application closed and 'dir' sent a FIN, 3328 * we're now going into LAST_ACK state 3329 */ 3330 nstate = IPF_TCPS_LAST_ACK; 3331 } else { 3332 /* 3333 * we remain in CLOSE_WAIT because the other 3334 * side has closed already and we did not 3335 * close our side yet; reset timeout 3336 */ 3337 nstate = IPF_TCPS_CLOSE_WAIT; 3338 } 3339 break; 3340 3341 case IPF_TCPS_FIN_WAIT_1: /* 7 */ 3342 rval = 1; 3343 if ((tcpflags & TH_ACK) && 3344 ostate > IPF_TCPS_CLOSE_WAIT) { 3345 /* 3346 * if the other side is not active anymore 3347 * it has sent us a FIN packet that we are 3348 * ack'ing now with an ACK; this means both 3349 * sides have now closed the connection and 3350 * we go into TIME_WAIT 3351 */ 3352 /* 3353 * XXX: how do we know we really are ACKing 3354 * the FIN packet here? does the window code 3355 * guarantee that? 3356 */ 3357 nstate = IPF_TCPS_TIME_WAIT; 3358 } else { 3359 /* 3360 * we closed our side of the connection 3361 * already but the other side is still active 3362 * (ESTABLISHED/CLOSE_WAIT); continue with 3363 * this half-closed connection 3364 */ 3365 nstate = IPF_TCPS_FIN_WAIT_1; 3366 } 3367 break; 3368 3369 case IPF_TCPS_CLOSING: /* 8 */ 3370 /* NOT USED */ 3371 break; 3372 3373 case IPF_TCPS_LAST_ACK: /* 9 */ 3374 if (tcpflags & TH_ACK) { 3375 if ((tcpflags & TH_PUSH) || dlen) 3376 /* 3377 * there is still data to be delivered, 3378 * reset timeout 3379 */ 3380 rval = 1; 3381 else 3382 rval = 2; 3383 } 3384 /* 3385 * we cannot detect when we go out of LAST_ACK state to 3386 * CLOSED because that is based on the reception of ACK 3387 * packets; ipfilter can only detect that a packet 3388 * has been sent by a host 3389 */ 3390 break; 3391 3392 case IPF_TCPS_FIN_WAIT_2: /* 10 */ 3393 rval = 1; 3394 if ((tcpflags & TH_OPENING) == TH_OPENING) 3395 nstate = IPF_TCPS_SYN_RECEIVED; 3396 else if (tcpflags & TH_SYN) 3397 nstate = IPF_TCPS_SYN_SENT; 3398 break; 3399 3400 case IPF_TCPS_TIME_WAIT: /* 11 */ 3401 /* we're in 2MSL timeout now */ 3402 rval = 1; 3403 break; 3404 3405 default : 3406 #if defined(_KERNEL) 3407 # if SOLARIS 3408 cmn_err(CE_NOTE, 3409 "tcp %lx flags %x si %lx nstate %d ostate %d\n", 3410 (u_long)tcp, tcpflags, (u_long)tqe, 3411 nstate, ostate); 3412 # else 3413 printf("tcp %lx flags %x si %lx nstate %d ostate %d\n", 3414 (u_long)tcp, tcpflags, (u_long)tqe, 3415 nstate, ostate); 3416 # endif 3417 #else 3418 abort(); 3419 #endif 3420 break; 3421 } 3422 } 3423 3424 /* 3425 * If rval == 2 then do not update the queue position, but treat the 3426 * packet as being ok. 3427 */ 3428 if (rval == 2) 3429 rval = 1; 3430 else if (rval == 1) { 3431 tqe->tqe_state[dir] = nstate; 3432 if ((tqe->tqe_flags & TQE_RULEBASED) == 0) 3433 fr_movequeue(tqe, tqe->tqe_ifq, tqtab + nstate, ifs); 3434 } 3435 3436 return rval; 3437 } 3438 3439 3440 /* ------------------------------------------------------------------------ */ 3441 /* Function: ipstate_log */ 3442 /* Returns: Nil */ 3443 /* Parameters: is(I) - pointer to state structure */ 3444 /* type(I) - type of log entry to create */ 3445 /* */ 3446 /* Creates a state table log entry using the state structure and type info. */ 3447 /* passed in. Log packet/byte counts, source/destination address and other */ 3448 /* protocol specific information. */ 3449 /* ------------------------------------------------------------------------ */ 3450 void ipstate_log(is, type, ifs) 3451 struct ipstate *is; 3452 u_int type; 3453 ipf_stack_t *ifs; 3454 { 3455 #ifdef IPFILTER_LOG 3456 struct ipslog ipsl; 3457 size_t sizes[1]; 3458 void *items[1]; 3459 int types[1]; 3460 3461 /* 3462 * Copy information out of the ipstate_t structure and into the 3463 * structure used for logging. 3464 */ 3465 ipsl.isl_type = type; 3466 ipsl.isl_pkts[0] = is->is_pkts[0] + is->is_icmppkts[0]; 3467 ipsl.isl_bytes[0] = is->is_bytes[0]; 3468 ipsl.isl_pkts[1] = is->is_pkts[1] + is->is_icmppkts[1]; 3469 ipsl.isl_bytes[1] = is->is_bytes[1]; 3470 ipsl.isl_pkts[2] = is->is_pkts[2] + is->is_icmppkts[2]; 3471 ipsl.isl_bytes[2] = is->is_bytes[2]; 3472 ipsl.isl_pkts[3] = is->is_pkts[3] + is->is_icmppkts[3]; 3473 ipsl.isl_bytes[3] = is->is_bytes[3]; 3474 ipsl.isl_src = is->is_src; 3475 ipsl.isl_dst = is->is_dst; 3476 ipsl.isl_p = is->is_p; 3477 ipsl.isl_v = is->is_v; 3478 ipsl.isl_flags = is->is_flags; 3479 ipsl.isl_tag = is->is_tag; 3480 ipsl.isl_rulen = is->is_rulen; 3481 (void) strncpy(ipsl.isl_group, is->is_group, FR_GROUPLEN); 3482 3483 if (ipsl.isl_p == IPPROTO_TCP || ipsl.isl_p == IPPROTO_UDP) { 3484 ipsl.isl_sport = is->is_sport; 3485 ipsl.isl_dport = is->is_dport; 3486 if (ipsl.isl_p == IPPROTO_TCP) { 3487 ipsl.isl_state[0] = is->is_state[0]; 3488 ipsl.isl_state[1] = is->is_state[1]; 3489 } 3490 } else if (ipsl.isl_p == IPPROTO_ICMP) { 3491 ipsl.isl_itype = is->is_icmp.ici_type; 3492 } else if (ipsl.isl_p == IPPROTO_ICMPV6) { 3493 ipsl.isl_itype = is->is_icmp.ici_type; 3494 } else { 3495 ipsl.isl_ps.isl_filler[0] = 0; 3496 ipsl.isl_ps.isl_filler[1] = 0; 3497 } 3498 3499 items[0] = &ipsl; 3500 sizes[0] = sizeof(ipsl); 3501 types[0] = 0; 3502 3503 if (ipllog(IPL_LOGSTATE, NULL, items, sizes, types, 1, ifs)) { 3504 ATOMIC_INCL(ifs->ifs_ips_stats.iss_logged); 3505 } else { 3506 ATOMIC_INCL(ifs->ifs_ips_stats.iss_logfail); 3507 } 3508 #endif 3509 } 3510 3511 3512 #ifdef USE_INET6 3513 /* ------------------------------------------------------------------------ */ 3514 /* Function: fr_checkicmp6matchingstate */ 3515 /* Returns: ipstate_t* - NULL == no match found, */ 3516 /* else pointer to matching state entry */ 3517 /* Parameters: fin(I) - pointer to packet information */ 3518 /* Locks: NULL == no locks, else Read Lock on ipf_state */ 3519 /* */ 3520 /* If we've got an ICMPv6 error message, using the information stored in */ 3521 /* the ICMPv6 packet, look for a matching state table entry. */ 3522 /* ------------------------------------------------------------------------ */ 3523 static ipstate_t *fr_checkicmp6matchingstate(fin) 3524 fr_info_t *fin; 3525 { 3526 struct icmp6_hdr *ic6, *oic; 3527 int backward, i; 3528 ipstate_t *is, **isp; 3529 u_short sport, dport; 3530 i6addr_t dst, src; 3531 u_short savelen; 3532 icmpinfo_t *ic; 3533 fr_info_t ofin; 3534 tcphdr_t *tcp; 3535 ip6_t *oip6; 3536 u_char pr; 3537 u_int hv; 3538 ipf_stack_t *ifs = fin->fin_ifs; 3539 3540 /* 3541 * Does it at least have the return (basic) IP header ? 3542 * Is it an actual recognised ICMP error type? 3543 * Only a basic IP header (no options) should be with 3544 * an ICMP error header. 3545 */ 3546 if ((fin->fin_v != 6) || (fin->fin_plen < ICMP6ERR_MINPKTLEN) || 3547 !(fin->fin_flx & FI_ICMPERR)) 3548 return NULL; 3549 3550 ic6 = fin->fin_dp; 3551 3552 oip6 = (ip6_t *)((char *)ic6 + ICMPERR_ICMPHLEN); 3553 if (fin->fin_plen < sizeof(*oip6)) 3554 return NULL; 3555 3556 bcopy((char *)fin, (char *)&ofin, sizeof(*fin)); 3557 ofin.fin_v = 6; 3558 ofin.fin_ifp = fin->fin_ifp; 3559 ofin.fin_out = !fin->fin_out; 3560 ofin.fin_m = NULL; /* if dereferenced, panic XXX */ 3561 ofin.fin_mp = NULL; /* if dereferenced, panic XXX */ 3562 3563 /* 3564 * We make a fin entry to be able to feed it to 3565 * matchsrcdst. Note that not all fields are necessary 3566 * but this is the cleanest way. Note further we fill 3567 * in fin_mp such that if someone uses it we'll get 3568 * a kernel panic. fr_matchsrcdst does not use this. 3569 * 3570 * watch out here, as ip is in host order and oip6 in network 3571 * order. Any change we make must be undone afterwards. 3572 */ 3573 savelen = oip6->ip6_plen; 3574 oip6->ip6_plen = fin->fin_dlen - ICMPERR_ICMPHLEN; 3575 ofin.fin_flx = FI_NOCKSUM; 3576 ofin.fin_ip = (ip_t *)oip6; 3577 ofin.fin_plen = oip6->ip6_plen; 3578 (void) fr_makefrip(sizeof(*oip6), (ip_t *)oip6, &ofin); 3579 ofin.fin_flx &= ~(FI_BAD|FI_SHORT); 3580 oip6->ip6_plen = savelen; 3581 3582 if (oip6->ip6_nxt == IPPROTO_ICMPV6) { 3583 oic = (struct icmp6_hdr *)(oip6 + 1); 3584 /* 3585 * an ICMP error can only be generated as a result of an 3586 * ICMP query, not as the response on an ICMP error 3587 * 3588 * XXX theoretically ICMP_ECHOREP and the other reply's are 3589 * ICMP query's as well, but adding them here seems strange XXX 3590 */ 3591 if (!(oic->icmp6_type & ICMP6_INFOMSG_MASK)) 3592 return NULL; 3593 3594 /* 3595 * perform a lookup of the ICMP packet in the state table 3596 */ 3597 hv = (pr = oip6->ip6_nxt); 3598 src.in6 = oip6->ip6_src; 3599 hv += src.in4.s_addr; 3600 dst.in6 = oip6->ip6_dst; 3601 hv += dst.in4.s_addr; 3602 hv += oic->icmp6_id; 3603 hv += oic->icmp6_seq; 3604 hv = DOUBLE_HASH(hv, ifs); 3605 3606 READ_ENTER(&ifs->ifs_ipf_state); 3607 for (isp = &ifs->ifs_ips_table[hv]; ((is = *isp) != NULL); ) { 3608 ic = &is->is_icmp; 3609 isp = &is->is_hnext; 3610 if ((is->is_p == pr) && 3611 !(is->is_pass & FR_NOICMPERR) && 3612 (oic->icmp6_id == ic->ici_id) && 3613 (oic->icmp6_seq == ic->ici_seq) && 3614 (is = fr_matchsrcdst(&ofin, is, &src, 3615 &dst, NULL, FI_ICMPCMP))) { 3616 /* 3617 * in the state table ICMP query's are stored 3618 * with the type of the corresponding ICMP 3619 * response. Correct here 3620 */ 3621 if (((ic->ici_type == ICMP6_ECHO_REPLY) && 3622 (oic->icmp6_type == ICMP6_ECHO_REQUEST)) || 3623 (ic->ici_type - 1 == oic->icmp6_type )) { 3624 ifs->ifs_ips_stats.iss_hits++; 3625 backward = IP6_NEQ(&is->is_dst, &src); 3626 fin->fin_rev = !backward; 3627 i = (backward << 1) + fin->fin_out; 3628 is->is_icmppkts[i]++; 3629 return is; 3630 } 3631 } 3632 } 3633 RWLOCK_EXIT(&ifs->ifs_ipf_state); 3634 return NULL; 3635 } 3636 3637 hv = (pr = oip6->ip6_nxt); 3638 src.in6 = oip6->ip6_src; 3639 hv += src.i6[0]; 3640 hv += src.i6[1]; 3641 hv += src.i6[2]; 3642 hv += src.i6[3]; 3643 dst.in6 = oip6->ip6_dst; 3644 hv += dst.i6[0]; 3645 hv += dst.i6[1]; 3646 hv += dst.i6[2]; 3647 hv += dst.i6[3]; 3648 3649 if ((oip6->ip6_nxt == IPPROTO_TCP) || (oip6->ip6_nxt == IPPROTO_UDP)) { 3650 tcp = (tcphdr_t *)(oip6 + 1); 3651 dport = tcp->th_dport; 3652 sport = tcp->th_sport; 3653 hv += dport; 3654 hv += sport; 3655 } else 3656 tcp = NULL; 3657 hv = DOUBLE_HASH(hv, ifs); 3658 3659 READ_ENTER(&ifs->ifs_ipf_state); 3660 for (isp = &ifs->ifs_ips_table[hv]; ((is = *isp) != NULL); ) { 3661 isp = &is->is_hnext; 3662 /* 3663 * Only allow this icmp though if the 3664 * encapsulated packet was allowed through the 3665 * other way around. Note that the minimal amount 3666 * of info present does not allow for checking against 3667 * tcp internals such as seq and ack numbers. 3668 */ 3669 if ((is->is_p != pr) || (is->is_v != 6) || 3670 (is->is_pass & FR_NOICMPERR)) 3671 continue; 3672 is = fr_matchsrcdst(&ofin, is, &src, &dst, tcp, FI_ICMPCMP); 3673 if (is != NULL) { 3674 ifs->ifs_ips_stats.iss_hits++; 3675 backward = IP6_NEQ(&is->is_dst, &src); 3676 fin->fin_rev = !backward; 3677 i = (backward << 1) + fin->fin_out; 3678 is->is_icmppkts[i]++; 3679 /* 3680 * we deliberately do not touch the timeouts 3681 * for the accompanying state table entry. 3682 * It remains to be seen if that is correct. XXX 3683 */ 3684 return is; 3685 } 3686 } 3687 RWLOCK_EXIT(&ifs->ifs_ipf_state); 3688 return NULL; 3689 } 3690 #endif 3691 3692 3693 /* ------------------------------------------------------------------------ */ 3694 /* Function: fr_sttab_init */ 3695 /* Returns: Nil */ 3696 /* Parameters: tqp(I) - pointer to an array of timeout queues for TCP */ 3697 /* */ 3698 /* Initialise the array of timeout queues for TCP. */ 3699 /* ------------------------------------------------------------------------ */ 3700 void fr_sttab_init(tqp, ifs) 3701 ipftq_t *tqp; 3702 ipf_stack_t *ifs; 3703 { 3704 int i; 3705 3706 for (i = IPF_TCP_NSTATES - 1; i >= 0; i--) { 3707 tqp[i].ifq_ttl = 0; 3708 tqp[i].ifq_ref = 1; 3709 tqp[i].ifq_head = NULL; 3710 tqp[i].ifq_tail = &tqp[i].ifq_head; 3711 tqp[i].ifq_next = tqp + i + 1; 3712 MUTEX_INIT(&tqp[i].ifq_lock, "ipftq tcp tab"); 3713 } 3714 tqp[IPF_TCP_NSTATES - 1].ifq_next = NULL; 3715 tqp[IPF_TCPS_CLOSED].ifq_ttl = ifs->ifs_fr_tcpclosed; 3716 tqp[IPF_TCPS_LISTEN].ifq_ttl = ifs->ifs_fr_tcptimeout; 3717 tqp[IPF_TCPS_SYN_SENT].ifq_ttl = ifs->ifs_fr_tcptimeout; 3718 tqp[IPF_TCPS_SYN_RECEIVED].ifq_ttl = ifs->ifs_fr_tcptimeout; 3719 tqp[IPF_TCPS_ESTABLISHED].ifq_ttl = ifs->ifs_fr_tcpidletimeout; 3720 tqp[IPF_TCPS_CLOSE_WAIT].ifq_ttl = ifs->ifs_fr_tcphalfclosed; 3721 tqp[IPF_TCPS_FIN_WAIT_1].ifq_ttl = ifs->ifs_fr_tcphalfclosed; 3722 tqp[IPF_TCPS_CLOSING].ifq_ttl = ifs->ifs_fr_tcptimeout; 3723 tqp[IPF_TCPS_LAST_ACK].ifq_ttl = ifs->ifs_fr_tcplastack; 3724 tqp[IPF_TCPS_FIN_WAIT_2].ifq_ttl = ifs->ifs_fr_tcpclosewait; 3725 tqp[IPF_TCPS_TIME_WAIT].ifq_ttl = ifs->ifs_fr_tcptimeout; 3726 tqp[IPF_TCPS_HALF_ESTAB].ifq_ttl = ifs->ifs_fr_tcptimeout; 3727 } 3728 3729 3730 /* ------------------------------------------------------------------------ */ 3731 /* Function: fr_sttab_destroy */ 3732 /* Returns: Nil */ 3733 /* Parameters: tqp(I) - pointer to an array of timeout queues for TCP */ 3734 /* */ 3735 /* Do whatever is necessary to "destroy" each of the entries in the array */ 3736 /* of timeout queues for TCP. */ 3737 /* ------------------------------------------------------------------------ */ 3738 void fr_sttab_destroy(tqp) 3739 ipftq_t *tqp; 3740 { 3741 int i; 3742 3743 for (i = IPF_TCP_NSTATES - 1; i >= 0; i--) 3744 MUTEX_DESTROY(&tqp[i].ifq_lock); 3745 } 3746 3747 3748 /* ------------------------------------------------------------------------ */ 3749 /* Function: fr_statederef */ 3750 /* Returns: Nil */ 3751 /* Parameters: isp(I) - pointer to pointer to state table entry */ 3752 /* */ 3753 /* Decrement the reference counter for this state table entry and free it */ 3754 /* if there are no more things using it. */ 3755 /* */ 3756 /* When operating in userland (ipftest), we have no timers to clear a state */ 3757 /* entry. Therefore, we make a few simple tests before deleting an entry */ 3758 /* outright. We compare states on each side looking for a combination of */ 3759 /* TIME_WAIT (should really be FIN_WAIT_2?) and LAST_ACK. Then we factor */ 3760 /* in packet direction with the interface list to make sure we don't */ 3761 /* prematurely delete an entry on a final inbound packet that's we're also */ 3762 /* supposed to route elsewhere. */ 3763 /* */ 3764 /* Internal parameters: */ 3765 /* state[0] = state of source (host that initiated connection) */ 3766 /* state[1] = state of dest (host that accepted the connection) */ 3767 /* */ 3768 /* dir == 0 : a packet from source to dest */ 3769 /* dir == 1 : a packet from dest to source */ 3770 /* ------------------------------------------------------------------------ */ 3771 void fr_statederef(fin, isp, ifs) 3772 fr_info_t *fin; 3773 ipstate_t **isp; 3774 ipf_stack_t *ifs; 3775 { 3776 ipstate_t *is = *isp; 3777 #if 0 3778 int nstate, ostate, dir, eol; 3779 3780 eol = 0; /* End-of-the-line flag. */ 3781 dir = fin->fin_rev; 3782 ostate = is->is_state[1 - dir]; 3783 nstate = is->is_state[dir]; 3784 /* 3785 * Determine whether this packet is local or routed. State entries 3786 * with us as the destination will have an interface list of 3787 * int1,-,-,int1. Entries with us as the origin run as -,int1,int1,-. 3788 */ 3789 if ((fin->fin_p == IPPROTO_TCP) && (fin->fin_out == 0)) { 3790 if ((strcmp(is->is_ifname[0], is->is_ifname[3]) == 0) && 3791 (strcmp(is->is_ifname[1], is->is_ifname[2]) == 0)) { 3792 if ((dir == 0) && 3793 (strcmp(is->is_ifname[1], "-") == 0) && 3794 (strcmp(is->is_ifname[0], "-") != 0)) { 3795 eol = 1; 3796 } else if ((dir == 1) && 3797 (strcmp(is->is_ifname[0], "-") == 0) && 3798 (strcmp(is->is_ifname[1], "-") != 0)) { 3799 eol = 1; 3800 } 3801 } 3802 } 3803 #endif 3804 3805 fin = fin; /* LINT */ 3806 is = *isp; 3807 *isp = NULL; 3808 WRITE_ENTER(&ifs->ifs_ipf_state); 3809 is->is_ref--; 3810 if (is->is_ref == 0) { 3811 is->is_ref++; /* To counter ref-- in fr_delstate() */ 3812 fr_delstate(is, ISL_EXPIRE, ifs); 3813 #ifndef _KERNEL 3814 #if 0 3815 } else if (((fin->fin_out == 1) || (eol == 1)) && 3816 ((ostate == IPF_TCPS_LAST_ACK) && 3817 (nstate == IPF_TCPS_TIME_WAIT))) { 3818 ; 3819 #else 3820 } else if ((is->is_sti.tqe_state[0] > IPF_TCPS_ESTABLISHED) || 3821 (is->is_sti.tqe_state[1] > IPF_TCPS_ESTABLISHED)) { 3822 #endif 3823 fr_delstate(is, ISL_ORPHAN, ifs); 3824 #endif 3825 } 3826 RWLOCK_EXIT(&ifs->ifs_ipf_state); 3827 } 3828 3829 3830 /* ------------------------------------------------------------------------ */ 3831 /* Function: fr_setstatequeue */ 3832 /* Returns: Nil */ 3833 /* Parameters: is(I) - pointer to state structure */ 3834 /* rev(I) - forward(0) or reverse(1) direction */ 3835 /* Locks: ipf_state (read or write) */ 3836 /* */ 3837 /* Put the state entry on its default queue entry, using rev as a helped in */ 3838 /* determining which queue it should be placed on. */ 3839 /* ------------------------------------------------------------------------ */ 3840 void fr_setstatequeue(is, rev, ifs) 3841 ipstate_t *is; 3842 int rev; 3843 ipf_stack_t *ifs; 3844 { 3845 ipftq_t *oifq, *nifq; 3846 3847 3848 if ((is->is_sti.tqe_flags & TQE_RULEBASED) != 0) 3849 nifq = is->is_tqehead[rev]; 3850 else 3851 nifq = NULL; 3852 3853 if (nifq == NULL) { 3854 switch (is->is_p) 3855 { 3856 #ifdef USE_INET6 3857 case IPPROTO_ICMPV6 : 3858 if (rev == 1) 3859 nifq = &ifs->ifs_ips_icmpacktq; 3860 else 3861 nifq = &ifs->ifs_ips_icmptq; 3862 break; 3863 #endif 3864 case IPPROTO_ICMP : 3865 if (rev == 1) 3866 nifq = &ifs->ifs_ips_icmpacktq; 3867 else 3868 nifq = &ifs->ifs_ips_icmptq; 3869 break; 3870 case IPPROTO_TCP : 3871 nifq = ifs->ifs_ips_tqtqb + is->is_state[rev]; 3872 break; 3873 3874 case IPPROTO_UDP : 3875 if (rev == 1) 3876 nifq = &ifs->ifs_ips_udpacktq; 3877 else 3878 nifq = &ifs->ifs_ips_udptq; 3879 break; 3880 3881 default : 3882 nifq = &ifs->ifs_ips_iptq; 3883 break; 3884 } 3885 } 3886 3887 oifq = is->is_sti.tqe_ifq; 3888 /* 3889 * If it's currently on a timeout queue, move it from one queue to 3890 * another, else put it on the end of the newly determined queue. 3891 */ 3892 if (oifq != NULL) 3893 fr_movequeue(&is->is_sti, oifq, nifq, ifs); 3894 else 3895 fr_queueappend(&is->is_sti, nifq, is, ifs); 3896 return; 3897 } 3898 3899 3900 /* ------------------------------------------------------------------------ */ 3901 /* Function: fr_stateiter */ 3902 /* Returns: int - 0 == success, else error */ 3903 /* Parameters: token(I) - pointer to ipftoken structure */ 3904 /* itp(I) - pointer to ipfgeniter structure */ 3905 /* */ 3906 /* This function handles the SIOCGENITER ioctl for the state tables and */ 3907 /* walks through the list of entries in the state table list (ips_list.) */ 3908 /* ------------------------------------------------------------------------ */ 3909 static int fr_stateiter(token, itp, ifs) 3910 ipftoken_t *token; 3911 ipfgeniter_t *itp; 3912 ipf_stack_t *ifs; 3913 { 3914 ipstate_t *is, *next, zero; 3915 int error; 3916 3917 if (itp->igi_data == NULL) 3918 return EFAULT; 3919 3920 if (itp->igi_type != IPFGENITER_STATE) 3921 return EINVAL; 3922 3923 is = token->ipt_data; 3924 if (is == (void *)-1) { 3925 ipf_freetoken(token, ifs); 3926 return ESRCH; 3927 } 3928 3929 READ_ENTER(&ifs->ifs_ipf_state); 3930 if (is == NULL) { 3931 next = ifs->ifs_ips_list; 3932 } else { 3933 next = is->is_next; 3934 } 3935 3936 if (next != NULL) { 3937 /* 3938 * If we find a state entry to use, bump its reference count 3939 * so that it can be used for is_next when we come back. 3940 */ 3941 MUTEX_ENTER(&next->is_lock); 3942 next->is_ref++; 3943 MUTEX_EXIT(&next->is_lock); 3944 token->ipt_data = next; 3945 } else { 3946 bzero(&zero, sizeof(zero)); 3947 next = &zero; 3948 token->ipt_data = (void *)-1; 3949 } 3950 RWLOCK_EXIT(&ifs->ifs_ipf_state); 3951 3952 /* 3953 * If we had a prior pointer to a state entry, release it. 3954 */ 3955 if (is != NULL) { 3956 fr_statederef(NULL, &is, ifs); 3957 } 3958 3959 /* 3960 * This should arguably be via fr_outobj() so that the state 3961 * structure can (if required) be massaged going out. 3962 */ 3963 error = COPYOUT(next, itp->igi_data, sizeof(*next)); 3964 if (error != 0) 3965 error = EFAULT; 3966 3967 return error; 3968 } 3969 3970