ip_frag.c revision 1.2.2.2
1 /* $NetBSD: ip_frag.c,v 1.2.2.2 2012/04/17 19:25:18 joerg Exp $ */ 2 3 /* 4 * Copyright (C) 2012 by Darren Reed. 5 * 6 * See the IPFILTER.LICENCE file for details on licencing. 7 */ 8 #if defined(KERNEL) || defined(_KERNEL) 9 # undef KERNEL 10 # undef _KERNEL 11 # define KERNEL 1 12 # define _KERNEL 1 13 #endif 14 #include <sys/errno.h> 15 #include <sys/types.h> 16 #include <sys/param.h> 17 #include <sys/time.h> 18 #include <sys/file.h> 19 #ifdef __hpux 20 # include <sys/timeout.h> 21 #endif 22 #if !defined(_KERNEL) 23 # include <stdio.h> 24 # include <string.h> 25 # include <stdlib.h> 26 # define _KERNEL 27 # ifdef __OpenBSD__ 28 struct file; 29 # endif 30 # include <sys/uio.h> 31 # undef _KERNEL 32 #endif 33 #if defined(_KERNEL) && \ 34 defined(__FreeBSD_version) && (__FreeBSD_version >= 220000) 35 # include <sys/filio.h> 36 # include <sys/fcntl.h> 37 #else 38 # include <sys/ioctl.h> 39 #endif 40 #if !defined(linux) 41 # include <sys/protosw.h> 42 #endif 43 #include <sys/socket.h> 44 #if defined(_KERNEL) 45 # include <sys/systm.h> 46 # if !defined(__SVR4) && !defined(__svr4__) 47 # include <sys/mbuf.h> 48 # endif 49 #endif 50 #if !defined(__SVR4) && !defined(__svr4__) 51 # if defined(_KERNEL) && !defined(__sgi) && !defined(AIX) 52 # include <sys/kernel.h> 53 # endif 54 #else 55 # include <sys/byteorder.h> 56 # ifdef _KERNEL 57 # include <sys/dditypes.h> 58 # endif 59 # include <sys/stream.h> 60 # include <sys/kmem.h> 61 #endif 62 #include <net/if.h> 63 #ifdef sun 64 # include <net/af.h> 65 #endif 66 #include <netinet/in.h> 67 #include <netinet/in_systm.h> 68 #include <netinet/ip.h> 69 #if !defined(linux) 70 # include <netinet/ip_var.h> 71 #endif 72 #include <netinet/tcp.h> 73 #include <netinet/udp.h> 74 #include <netinet/ip_icmp.h> 75 #include "netinet/ip_compat.h" 76 #include <netinet/tcpip.h> 77 #include "netinet/ip_fil.h" 78 #include "netinet/ip_nat.h" 79 #include "netinet/ip_frag.h" 80 #include "netinet/ip_state.h" 81 #include "netinet/ip_auth.h" 82 #include "netinet/ip_lookup.h" 83 #include "netinet/ip_proxy.h" 84 #include "netinet/ip_sync.h" 85 /* END OF INCLUDES */ 86 87 #if !defined(lint) 88 #if defined(__NetBSD__) 89 #include <sys/cdefs.h> 90 __KERNEL_RCSID(0, "$NetBSD: ip_frag.c,v 1.2.2.2 2012/04/17 19:25:18 joerg Exp $"); 91 #else 92 static const char sccsid[] = "@(#)ip_frag.c 1.11 3/24/96 (C) 1993-2000 Darren Reed"; 93 static const char rcsid[] = "@(#)Id: ip_frag.c,v 2.110.2.9 2012/01/29 05:30:36 darrenr Exp"; 94 #endif 95 #endif 96 97 98 typedef struct ipf_frag_softc_s { 99 ipfrwlock_t ipfr_ipidfrag; 100 ipfrwlock_t ipfr_frag; 101 ipfrwlock_t ipfr_natfrag; 102 int ipfr_size; 103 int ipfr_ttl; 104 int ipfr_lock; 105 int ipfr_inited; 106 ipfr_t *ipfr_list; 107 ipfr_t **ipfr_tail; 108 ipfr_t *ipfr_natlist; 109 ipfr_t **ipfr_nattail; 110 ipfr_t *ipfr_ipidlist; 111 ipfr_t **ipfr_ipidtail; 112 ipfr_t **ipfr_heads; 113 ipfr_t **ipfr_nattab; 114 ipfr_t **ipfr_ipidtab; 115 ipfrstat_t ipfr_stats; 116 } ipf_frag_softc_t; 117 118 119 #ifdef USE_MUTEXES 120 static ipfr_t *ipfr_frag_new(ipf_main_softc_t *, ipf_frag_softc_t *, 121 fr_info_t *, u_32_t, ipfr_t **, 122 ipfrwlock_t *); 123 static ipfr_t *ipf_frag_lookup(ipf_main_softc_t *, ipf_frag_softc_t *, fr_info_t *, ipfr_t **, ipfrwlock_t *); 124 static void ipf_frag_deref(void *, ipfr_t **, ipfrwlock_t *); 125 static int ipf_frag_next(ipf_main_softc_t *, ipftoken_t *, ipfgeniter_t *, 126 ipfr_t **, ipfrwlock_t *); 127 #else 128 static ipfr_t *ipfr_frag_new(ipf_main_softc_t *, ipf_frag_softc_t *, 129 fr_info_t *, u_32_t, ipfr_t **); 130 static ipfr_t *ipf_frag_lookup(ipf_main_softc_t *, ipf_frag_softc_t *, fr_info_t *, ipfr_t **); 131 static void ipf_frag_deref(void *, ipfr_t **); 132 static int ipf_frag_next(ipf_main_softc_t *, ipftoken_t *, ipfgeniter_t *, 133 ipfr_t **); 134 #endif 135 static void ipf_frag_delete(ipf_main_softc_t *, ipfr_t *, ipfr_t ***); 136 static void ipf_frag_free(ipf_frag_softc_t *, ipfr_t *); 137 138 static frentry_t ipfr_block; 139 140 ipftuneable_t ipf_tuneables[] = { 141 { { (void *)offsetof(ipf_frag_softc_t, ipfr_size) }, 142 "frag_size", 1, 0x7fffffff, 143 stsizeof(ipf_frag_softc_t, ipfr_size), 144 IPFT_WRDISABLED, NULL, NULL }, 145 { { (void *)offsetof(ipf_frag_softc_t, ipfr_ttl) }, 146 "frag_ttl", 1, 0x7fffffff, 147 stsizeof(ipf_frag_softc_t, ipfr_ttl), 148 0, NULL, NULL }, 149 { { NULL }, 150 NULL, 0, 0, 151 0, 152 0, NULL, NULL } 153 }; 154 155 #define FBUMP(x) softf->ipfr_stats.x++ 156 #define FBUMPD(x) do { softf->ipfr_stats.x++; DT(x); } while (0) 157 158 159 /* ------------------------------------------------------------------------ */ 160 /* Function: ipf_frag_main_load */ 161 /* Returns: int - 0 == success, -1 == error */ 162 /* Parameters: Nil */ 163 /* */ 164 /* Initialise the filter rule associted with blocked packets - everyone can */ 165 /* use it. */ 166 /* ------------------------------------------------------------------------ */ 167 int 168 ipf_frag_main_load(void) 169 { 170 bzero((char *)&ipfr_block, sizeof(ipfr_block)); 171 ipfr_block.fr_flags = FR_BLOCK|FR_QUICK; 172 ipfr_block.fr_ref = 1; 173 174 return 0; 175 } 176 177 178 /* ------------------------------------------------------------------------ */ 179 /* Function: ipf_frag_main_unload */ 180 /* Returns: int - 0 == success, -1 == error */ 181 /* Parameters: Nil */ 182 /* */ 183 /* A null-op function that exists as a placeholder so that the flow in */ 184 /* other functions is obvious. */ 185 /* ------------------------------------------------------------------------ */ 186 int 187 ipf_frag_main_unload(void) 188 { 189 return 0; 190 } 191 192 193 /* ------------------------------------------------------------------------ */ 194 /* Function: ipf_frag_soft_create */ 195 /* Returns: void * - NULL = failure, else pointer to local context */ 196 /* Parameters: softc(I) - pointer to soft context main structure */ 197 /* */ 198 /* Allocate a new soft context structure to track fragment related info. */ 199 /* ------------------------------------------------------------------------ */ 200 /*ARGSUSED*/ 201 void * 202 ipf_frag_soft_create(ipf_main_softc_t *softc) 203 { 204 ipf_frag_softc_t *softf; 205 206 KMALLOC(softf, ipf_frag_softc_t *); 207 if (softf == NULL) 208 return NULL; 209 210 bzero((char *)softf, sizeof(*softf)); 211 212 RWLOCK_INIT(&softf->ipfr_ipidfrag, "frag ipid lock"); 213 RWLOCK_INIT(&softf->ipfr_frag, "ipf fragment rwlock"); 214 RWLOCK_INIT(&softf->ipfr_natfrag, "ipf NAT fragment rwlock"); 215 216 softf->ipfr_size = IPFT_SIZE; 217 softf->ipfr_ttl = IPF_TTLVAL(60); 218 softf->ipfr_lock = 1; 219 softf->ipfr_tail = &softf->ipfr_list; 220 softf->ipfr_nattail = &softf->ipfr_natlist; 221 softf->ipfr_ipidtail = &softf->ipfr_ipidlist; 222 223 return softf; 224 } 225 226 227 /* ------------------------------------------------------------------------ */ 228 /* Function: ipf_frag_soft_destroy */ 229 /* Returns: Nil */ 230 /* Parameters: softc(I) - pointer to soft context main structure */ 231 /* arg(I) - pointer to local context to use */ 232 /* */ 233 /* Initialise the hash tables for the fragment cache lookups. */ 234 /* ------------------------------------------------------------------------ */ 235 void 236 ipf_frag_soft_destroy(ipf_main_softc_t *softc, void *arg) 237 { 238 ipf_frag_softc_t *softf = arg; 239 240 RW_DESTROY(&softf->ipfr_ipidfrag); 241 RW_DESTROY(&softf->ipfr_frag); 242 RW_DESTROY(&softf->ipfr_natfrag); 243 244 KFREE(softf); 245 } 246 247 248 /* ------------------------------------------------------------------------ */ 249 /* Function: ipf_frag_soft_init */ 250 /* Returns: int - 0 == success, -1 == error */ 251 /* Parameters: softc(I) - pointer to soft context main structure */ 252 /* arg(I) - pointer to local context to use */ 253 /* */ 254 /* Initialise the hash tables for the fragment cache lookups. */ 255 /* ------------------------------------------------------------------------ */ 256 /*ARGSUSED*/ 257 int 258 ipf_frag_soft_init(ipf_main_softc_t *softc, void *arg) 259 { 260 ipf_frag_softc_t *softf = arg; 261 262 KMALLOCS(softf->ipfr_heads, ipfr_t **, 263 softf->ipfr_size * sizeof(ipfr_t *)); 264 if (softf->ipfr_heads == NULL) 265 return -1; 266 267 bzero((char *)softf->ipfr_heads, softf->ipfr_size * sizeof(ipfr_t *)); 268 269 KMALLOCS(softf->ipfr_nattab, ipfr_t **, 270 softf->ipfr_size * sizeof(ipfr_t *)); 271 if (softf->ipfr_nattab == NULL) 272 return -2; 273 274 bzero((char *)softf->ipfr_nattab, softf->ipfr_size * sizeof(ipfr_t *)); 275 276 KMALLOCS(softf->ipfr_ipidtab, ipfr_t **, 277 softf->ipfr_size * sizeof(ipfr_t *)); 278 if (softf->ipfr_ipidtab == NULL) 279 return -3; 280 281 bzero((char *)softf->ipfr_ipidtab, 282 softf->ipfr_size * sizeof(ipfr_t *)); 283 284 softf->ipfr_lock = 0; 285 softf->ipfr_inited = 1; 286 287 return 0; 288 } 289 290 291 /* ------------------------------------------------------------------------ */ 292 /* Function: ipf_frag_soft_fini */ 293 /* Returns: int - 0 == success, -1 == error */ 294 /* Parameters: softc(I) - pointer to soft context main structure */ 295 /* arg(I) - pointer to local context to use */ 296 /* */ 297 /* Free all memory allocated whilst running and from initialisation. */ 298 /* ------------------------------------------------------------------------ */ 299 int 300 ipf_frag_soft_fini(ipf_main_softc_t *softc, void *arg) 301 { 302 ipf_frag_softc_t *softf = arg; 303 304 softf->ipfr_lock = 1; 305 306 if (softf->ipfr_inited == 1) { 307 ipf_frag_clear(softc); 308 309 softf->ipfr_inited = 0; 310 } 311 312 if (softf->ipfr_heads != NULL) 313 KFREES(softf->ipfr_heads, 314 softf->ipfr_size * sizeof(ipfr_t *)); 315 softf->ipfr_heads = NULL; 316 317 if (softf->ipfr_nattab != NULL) 318 KFREES(softf->ipfr_nattab, 319 softf->ipfr_size * sizeof(ipfr_t *)); 320 softf->ipfr_nattab = NULL; 321 322 if (softf->ipfr_ipidtab != NULL) 323 KFREES(softf->ipfr_ipidtab, 324 softf->ipfr_size * sizeof(ipfr_t *)); 325 softf->ipfr_ipidtab = NULL; 326 327 return 0; 328 } 329 330 331 /* ------------------------------------------------------------------------ */ 332 /* Function: ipf_frag_set_lock */ 333 /* Returns: Nil */ 334 /* Parameters: arg(I) - pointer to local context to use */ 335 /* tmp(I) - new value for lock */ 336 /* */ 337 /* Stub function that allows for external manipulation of ipfr_lock */ 338 /* ------------------------------------------------------------------------ */ 339 void 340 ipf_frag_setlock(void *arg, int tmp) 341 { 342 ipf_frag_softc_t *softf = arg; 343 344 softf->ipfr_lock = tmp; 345 } 346 347 348 /* ------------------------------------------------------------------------ */ 349 /* Function: ipf_frag_stats */ 350 /* Returns: ipfrstat_t* - pointer to struct with current frag stats */ 351 /* Parameters: arg(I) - pointer to local context to use */ 352 /* */ 353 /* Updates ipfr_stats with current information and returns a pointer to it */ 354 /* ------------------------------------------------------------------------ */ 355 ipfrstat_t * 356 ipf_frag_stats(void *arg) 357 { 358 ipf_frag_softc_t *softf = arg; 359 360 softf->ipfr_stats.ifs_table = softf->ipfr_heads; 361 softf->ipfr_stats.ifs_nattab = softf->ipfr_nattab; 362 return &softf->ipfr_stats; 363 } 364 365 366 /* ------------------------------------------------------------------------ */ 367 /* Function: ipfr_frag_new */ 368 /* Returns: ipfr_t * - pointer to fragment cache state info or NULL */ 369 /* Parameters: fin(I) - pointer to packet information */ 370 /* table(I) - pointer to frag table to add to */ 371 /* lock(I) - pointer to lock to get a write hold of */ 372 /* */ 373 /* Add a new entry to the fragment cache, registering it as having come */ 374 /* through this box, with the result of the filter operation. */ 375 /* */ 376 /* If this function succeeds, it returns with a write lock held on "lock". */ 377 /* If it fails, no lock is held on return. */ 378 /* ------------------------------------------------------------------------ */ 379 static ipfr_t * 380 ipfr_frag_new( 381 ipf_main_softc_t *softc, 382 ipf_frag_softc_t *softf, 383 fr_info_t *fin, 384 u_32_t pass, 385 ipfr_t *table[] 386 #ifdef USE_MUTEXES 387 , ipfrwlock_t *lock 388 #endif 389 ) 390 { 391 ipfr_t *fra, frag, *fran; 392 u_int idx, off; 393 frentry_t *fr; 394 395 if (softf->ipfr_stats.ifs_inuse >= softf->ipfr_size) { 396 FBUMPD(ifs_maximum); 397 return NULL; 398 } 399 400 if ((fin->fin_flx & (FI_FRAG|FI_BAD)) != FI_FRAG) { 401 FBUMPD(ifs_newbad); 402 return NULL; 403 } 404 405 if (pass & FR_FRSTRICT) { 406 if (fin->fin_off != 0) { 407 FBUMPD(ifs_newrestrictnot0); 408 return NULL; 409 } 410 } 411 412 frag.ipfr_v = fin->fin_v; 413 idx = fin->fin_v; 414 frag.ipfr_p = fin->fin_p; 415 idx += fin->fin_p; 416 frag.ipfr_id = fin->fin_id; 417 idx += fin->fin_id; 418 frag.ipfr_source = fin->fin_fi.fi_src; 419 idx += frag.ipfr_src.s_addr; 420 frag.ipfr_dest = fin->fin_fi.fi_dst; 421 idx += frag.ipfr_dst.s_addr; 422 frag.ipfr_ifp = fin->fin_ifp; 423 idx *= 127; 424 idx %= softf->ipfr_size; 425 426 frag.ipfr_optmsk = fin->fin_fi.fi_optmsk & IPF_OPTCOPY; 427 frag.ipfr_secmsk = fin->fin_fi.fi_secmsk; 428 frag.ipfr_auth = fin->fin_fi.fi_auth; 429 430 off = fin->fin_off >> 3; 431 #ifdef USE_INET6 432 if ((off == 0) && (fin->fin_v == 6)) { 433 char *ptr; 434 int end; 435 436 ptr = (char *)fin->fin_fraghdr + sizeof(struct ip6_frag); 437 end = fin->fin_plen - (ptr - (char *)fin->fin_ip); 438 frag.ipfr_firstend = end >> 3; 439 } else 440 #endif 441 frag.ipfr_firstend = 0; 442 443 /* 444 * allocate some memory, if possible, if not, just record that we 445 * failed to do so. 446 */ 447 KMALLOC(fran, ipfr_t *); 448 if (fran == NULL) { 449 FBUMPD(ifs_nomem); 450 return NULL; 451 } 452 453 WRITE_ENTER(lock); 454 455 /* 456 * first, make sure it isn't already there... 457 */ 458 for (fra = table[idx]; (fra != NULL); fra = fra->ipfr_hnext) 459 if (!bcmp((char *)&frag.ipfr_ifp, (char *)&fra->ipfr_ifp, 460 IPFR_CMPSZ)) { 461 RWLOCK_EXIT(lock); 462 FBUMPD(ifs_exists); 463 KFREE(fra); 464 return NULL; 465 } 466 467 fra = fran; 468 fran = NULL; 469 fr = fin->fin_fr; 470 fra->ipfr_rule = fr; 471 if (fr != NULL) { 472 MUTEX_ENTER(&fr->fr_lock); 473 fr->fr_ref++; 474 MUTEX_EXIT(&fr->fr_lock); 475 } 476 477 /* 478 * Insert the fragment into the fragment table, copy the struct used 479 * in the search using bcopy rather than reassign each field. 480 * Set the ttl to the default. 481 */ 482 if ((fra->ipfr_hnext = table[idx]) != NULL) 483 table[idx]->ipfr_hprev = &fra->ipfr_hnext; 484 fra->ipfr_hprev = table + idx; 485 fra->ipfr_data = NULL; 486 table[idx] = fra; 487 bcopy((char *)&frag.ipfr_ifp, (char *)&fra->ipfr_ifp, IPFR_CMPSZ); 488 fra->ipfr_v = fin->fin_v; 489 fra->ipfr_ttl = softc->ipf_ticks + softf->ipfr_ttl; 490 fra->ipfr_firstend = frag.ipfr_firstend; 491 492 /* 493 * Compute the offset of the expected start of the next packet. 494 */ 495 if (off == 0) 496 fra->ipfr_seen0 = 1; 497 fra->ipfr_off = off + (fin->fin_dlen >> 3); 498 fra->ipfr_pass = pass; 499 fra->ipfr_ref = 1; 500 fra->ipfr_pkts = 1; 501 fra->ipfr_bytes = fin->fin_plen; 502 FBUMP(ifs_inuse); 503 FBUMP(ifs_new); 504 return fra; 505 } 506 507 508 /* ------------------------------------------------------------------------ */ 509 /* Function: ipf_frag_new */ 510 /* Returns: int - 0 == success, -1 == error */ 511 /* Parameters: fin(I) - pointer to packet information */ 512 /* */ 513 /* Add a new entry to the fragment cache table based on the current packet */ 514 /* ------------------------------------------------------------------------ */ 515 int 516 ipf_frag_new(ipf_main_softc_t *softc, fr_info_t *fin, u_32_t pass) 517 { 518 ipf_frag_softc_t *softf = softc->ipf_frag_soft; 519 ipfr_t *fra; 520 521 if (softf->ipfr_lock != 0) 522 return -1; 523 524 #ifdef USE_MUTEXES 525 fra = ipfr_frag_new(softc, softf, fin, pass, softf->ipfr_heads, &softc->ipf_frag); 526 #else 527 fra = ipfr_frag_new(softc, softf, fin, pass, softf->ipfr_heads); 528 #endif 529 if (fra != NULL) { 530 *softf->ipfr_tail = fra; 531 fra->ipfr_prev = softf->ipfr_tail; 532 softf->ipfr_tail = &fra->ipfr_next; 533 fra->ipfr_next = NULL; 534 RWLOCK_EXIT(&softc->ipf_frag); 535 } 536 return fra ? 0 : -1; 537 } 538 539 540 /* ------------------------------------------------------------------------ */ 541 /* Function: ipf_frag_natnew */ 542 /* Returns: int - 0 == success, -1 == error */ 543 /* Parameters: fin(I) - pointer to packet information */ 544 /* nat(I) - pointer to NAT structure */ 545 /* */ 546 /* Create a new NAT fragment cache entry based on the current packet and */ 547 /* the NAT structure for this "session". */ 548 /* ------------------------------------------------------------------------ */ 549 int 550 ipf_frag_natnew(ipf_main_softc_t *softc, fr_info_t *fin, u_32_t pass, 551 nat_t *nat) 552 { 553 ipf_frag_softc_t *softf = softc->ipf_frag_soft; 554 ipfr_t *fra; 555 556 if ((fin->fin_v != 4) || (softf->ipfr_lock != 0)) 557 return 0; 558 559 #ifdef USE_MUTEXES 560 fra = ipfr_frag_new(softc, softf, fin, pass, softf->ipfr_nattab, 561 &softf->ipfr_natfrag); 562 #else 563 fra = ipfr_frag_new(softc, softf, fin, pass, softf->ipfr_nattab); 564 #endif 565 if (fra != NULL) { 566 fra->ipfr_data = nat; 567 nat->nat_data = fra; 568 *softf->ipfr_nattail = fra; 569 fra->ipfr_prev = softf->ipfr_nattail; 570 softf->ipfr_nattail = &fra->ipfr_next; 571 fra->ipfr_next = NULL; 572 RWLOCK_EXIT(&softf->ipfr_natfrag); 573 } 574 return fra ? 0 : -1; 575 } 576 577 578 /* ------------------------------------------------------------------------ */ 579 /* Function: ipf_frag_ipidnew */ 580 /* Returns: int - 0 == success, -1 == error */ 581 /* Parameters: fin(I) - pointer to packet information */ 582 /* ipid(I) - new IP ID for this fragmented packet */ 583 /* */ 584 /* Create a new fragment cache entry for this packet and store, as a data */ 585 /* pointer, the new IP ID value. */ 586 /* ------------------------------------------------------------------------ */ 587 int 588 ipf_frag_ipidnew(fr_info_t *fin, u_32_t ipid) 589 { 590 ipf_main_softc_t *softc = fin->fin_main_soft; 591 ipf_frag_softc_t *softf = softc->ipf_frag_soft; 592 ipfr_t *fra; 593 594 if (softf->ipfr_lock) 595 return 0; 596 597 #ifdef USE_MUTEXES 598 fra = ipfr_frag_new(softc, softf, fin, 0, softf->ipfr_ipidtab, &softf->ipfr_ipidfrag); 599 #else 600 fra = ipfr_frag_new(softc, softf, fin, 0, softf->ipfr_ipidtab); 601 #endif 602 if (fra != NULL) { 603 fra->ipfr_data = (void *)(intptr_t)ipid; 604 *softf->ipfr_ipidtail = fra; 605 fra->ipfr_prev = softf->ipfr_ipidtail; 606 softf->ipfr_ipidtail = &fra->ipfr_next; 607 fra->ipfr_next = NULL; 608 RWLOCK_EXIT(&softf->ipfr_ipidfrag); 609 } 610 return fra ? 0 : -1; 611 } 612 613 614 /* ------------------------------------------------------------------------ */ 615 /* Function: ipf_frag_lookup */ 616 /* Returns: ipfr_t * - pointer to ipfr_t structure if there's a */ 617 /* matching entry in the frag table, else NULL */ 618 /* Parameters: fin(I) - pointer to packet information */ 619 /* table(I) - pointer to fragment cache table to search */ 620 /* */ 621 /* Check the fragment cache to see if there is already a record of this */ 622 /* packet with its filter result known. */ 623 /* */ 624 /* If this function succeeds, it returns with a write lock held on "lock". */ 625 /* If it fails, no lock is held on return. */ 626 /* ------------------------------------------------------------------------ */ 627 static ipfr_t * 628 ipf_frag_lookup( 629 ipf_main_softc_t *softc, 630 ipf_frag_softc_t *softf, 631 fr_info_t *fin, 632 ipfr_t *table[] 633 #ifdef USE_MUTEXES 634 , ipfrwlock_t *lock 635 #endif 636 ) 637 { 638 ipfr_t *f, frag; 639 u_int idx; 640 641 /* 642 * We don't want to let short packets match because they could be 643 * compromising the security of other rules that want to match on 644 * layer 4 fields (and can't because they have been fragmented off.) 645 * Why do this check here? The counter acts as an indicator of this 646 * kind of attack, whereas if it was elsewhere, it wouldn't know if 647 * other matching packets had been seen. 648 */ 649 if (fin->fin_flx & FI_SHORT) { 650 FBUMPD(ifs_short); 651 return NULL; 652 } 653 654 if ((fin->fin_flx & FI_BAD) != 0) { 655 FBUMPD(ifs_bad); 656 return NULL; 657 } 658 659 /* 660 * For fragments, we record protocol, packet id, TOS and both IP#'s 661 * (these should all be the same for all fragments of a packet). 662 * 663 * build up a hash value to index the table with. 664 */ 665 frag.ipfr_v = fin->fin_v; 666 idx = fin->fin_v; 667 frag.ipfr_p = fin->fin_p; 668 idx += fin->fin_p; 669 frag.ipfr_id = fin->fin_id; 670 idx += fin->fin_id; 671 frag.ipfr_source = fin->fin_fi.fi_src; 672 idx += frag.ipfr_src.s_addr; 673 frag.ipfr_dest = fin->fin_fi.fi_dst; 674 idx += frag.ipfr_dst.s_addr; 675 frag.ipfr_ifp = fin->fin_ifp; 676 idx *= 127; 677 idx %= softf->ipfr_size; 678 679 frag.ipfr_optmsk = fin->fin_fi.fi_optmsk & IPF_OPTCOPY; 680 frag.ipfr_secmsk = fin->fin_fi.fi_secmsk; 681 frag.ipfr_auth = fin->fin_fi.fi_auth; 682 683 READ_ENTER(lock); 684 685 /* 686 * check the table, careful to only compare the right amount of data 687 */ 688 for (f = table[idx]; f; f = f->ipfr_hnext) { 689 if (!bcmp((char *)&frag.ipfr_ifp, (char *)&f->ipfr_ifp, 690 IPFR_CMPSZ)) { 691 u_short off; 692 693 /* 694 * XXX - We really need to be guarding against the 695 * retransmission of (src,dst,id,offset-range) here 696 * because a fragmented packet is never resent with 697 * the same IP ID# (or shouldn't). 698 */ 699 off = fin->fin_off >> 3; 700 if (f->ipfr_seen0) { 701 if (off == 0) { 702 FBUMPD(ifs_retrans0); 703 continue; 704 } 705 706 /* 707 * Case 3. See comment for frpr_fragment6. 708 */ 709 if ((f->ipfr_firstend != 0) && 710 (off < f->ipfr_firstend)) { 711 FBUMPD(ifs_overlap); 712 fin->fin_flx |= FI_BAD; 713 break; 714 } 715 } else if (off == 0) 716 f->ipfr_seen0 = 1; 717 718 if (f != table[idx]) { 719 ipfr_t **fp; 720 721 /* 722 * Move fragment info. to the top of the list 723 * to speed up searches. First, delink... 724 */ 725 fp = f->ipfr_hprev; 726 (*fp) = f->ipfr_hnext; 727 if (f->ipfr_hnext != NULL) 728 f->ipfr_hnext->ipfr_hprev = fp; 729 /* 730 * Then put back at the top of the chain. 731 */ 732 f->ipfr_hnext = table[idx]; 733 table[idx]->ipfr_hprev = &f->ipfr_hnext; 734 f->ipfr_hprev = table + idx; 735 table[idx] = f; 736 } 737 738 /* 739 * If we've follwed the fragments, and this is the 740 * last (in order), shrink expiration time. 741 */ 742 if (off == f->ipfr_off) { 743 f->ipfr_off = (fin->fin_dlen >> 3) + off; 744 745 /* 746 * Well, we could shrink the expiration time 747 * but only if every fragment has been seen 748 * in order upto this, the last. ipfr_badorder 749 * is used here to count those out of order 750 * and if it equals 0 when we get to the last 751 * fragment then we can assume all of the 752 * fragments have been seen and in order. 753 */ 754 #if 0 755 /* 756 * Doing this properly requires moving it to 757 * the head of the list which is infesible. 758 */ 759 if ((more == 0) && (f->ipfr_badorder == 0)) 760 f->ipfr_ttl = softc->ipf_ticks + 1; 761 #endif 762 } else { 763 f->ipfr_badorder++; 764 FBUMPD(ifs_unordered); 765 if (f->ipfr_pass & FR_FRSTRICT) { 766 FBUMPD(ifs_strict); 767 continue; 768 } 769 } 770 f->ipfr_pkts++; 771 f->ipfr_bytes += fin->fin_plen; 772 FBUMP(ifs_hits); 773 return f; 774 } 775 } 776 777 RWLOCK_EXIT(lock); 778 FBUMP(ifs_miss); 779 return NULL; 780 } 781 782 783 /* ------------------------------------------------------------------------ */ 784 /* Function: ipf_frag_natknown */ 785 /* Returns: nat_t* - pointer to 'parent' NAT structure if frag table */ 786 /* match found, else NULL */ 787 /* Parameters: fin(I) - pointer to packet information */ 788 /* */ 789 /* Functional interface for NAT lookups of the NAT fragment cache */ 790 /* ------------------------------------------------------------------------ */ 791 nat_t * 792 ipf_frag_natknown(fr_info_t *fin) 793 { 794 ipf_main_softc_t *softc = fin->fin_main_soft; 795 ipf_frag_softc_t *softf = softc->ipf_frag_soft; 796 nat_t *nat; 797 ipfr_t *ipf; 798 799 if ((softf->ipfr_lock) || !softf->ipfr_natlist) 800 return NULL; 801 #ifdef USE_MUTEXES 802 ipf = ipf_frag_lookup(softc, softf, fin, softf->ipfr_nattab, 803 &softf->ipfr_natfrag); 804 #else 805 ipf = ipf_frag_lookup(softc, softf, fin, softf->ipfr_nattab); 806 #endif 807 if (ipf != NULL) { 808 nat = ipf->ipfr_data; 809 /* 810 * This is the last fragment for this packet. 811 */ 812 if ((ipf->ipfr_ttl == softc->ipf_ticks + 1) && (nat != NULL)) { 813 nat->nat_data = NULL; 814 ipf->ipfr_data = NULL; 815 } 816 RWLOCK_EXIT(&softf->ipfr_natfrag); 817 } else 818 nat = NULL; 819 return nat; 820 } 821 822 823 /* ------------------------------------------------------------------------ */ 824 /* Function: ipf_frag_ipidknown */ 825 /* Returns: u_32_t - IPv4 ID for this packet if match found, else */ 826 /* return 0xfffffff to indicate no match. */ 827 /* Parameters: fin(I) - pointer to packet information */ 828 /* */ 829 /* Functional interface for IP ID lookups of the IP ID fragment cache */ 830 /* ------------------------------------------------------------------------ */ 831 u_32_t 832 ipf_frag_ipidknown(fr_info_t *fin) 833 { 834 ipf_main_softc_t *softc = fin->fin_main_soft; 835 ipf_frag_softc_t *softf = softc->ipf_frag_soft; 836 ipfr_t *ipf; 837 u_32_t id; 838 839 if ((fin->fin_v != 4) || (softf->ipfr_lock) || 840 !softf->ipfr_ipidlist) 841 return 0xffffffff; 842 843 #ifdef USE_MUTEXES 844 ipf = ipf_frag_lookup(softc, softf, fin, softf->ipfr_ipidtab, 845 &softf->ipfr_ipidfrag); 846 #else 847 ipf = ipf_frag_lookup(softc, softf, fin, softf->ipfr_ipidtab); 848 #endif 849 if (ipf != NULL) { 850 id = (u_32_t)(intptr_t)ipf->ipfr_data; 851 RWLOCK_EXIT(&softf->ipfr_ipidfrag); 852 } else 853 id = 0xffffffff; 854 return id; 855 } 856 857 858 /* ------------------------------------------------------------------------ */ 859 /* Function: ipf_frag_known */ 860 /* Returns: frentry_t* - pointer to filter rule if a match is found in */ 861 /* the frag cache table, else NULL. */ 862 /* Parameters: fin(I) - pointer to packet information */ 863 /* passp(O) - pointer to where to store rule flags resturned */ 864 /* */ 865 /* Functional interface for normal lookups of the fragment cache. If a */ 866 /* match is found, return the rule pointer and flags from the rule, except */ 867 /* that if FR_LOGFIRST is set, reset FR_LOG. */ 868 /* ------------------------------------------------------------------------ */ 869 frentry_t * 870 ipf_frag_known(fr_info_t *fin, u_32_t *passp) 871 { 872 ipf_main_softc_t *softc = fin->fin_main_soft; 873 ipf_frag_softc_t *softf = softc->ipf_frag_soft; 874 frentry_t *fr = NULL; 875 ipfr_t *fra; 876 u_32_t pass; 877 878 if ((softf->ipfr_lock) || (softf->ipfr_list == NULL)) 879 return NULL; 880 881 #ifdef USE_MUTEXES 882 fra = ipf_frag_lookup(softc, softf, fin, softf->ipfr_heads, 883 &softc->ipf_frag); 884 #else 885 fra = ipf_frag_lookup(softc, softf, fin, softf->ipfr_heads); 886 #endif 887 if (fra != NULL) { 888 if (fin->fin_flx & FI_BAD) { 889 fr = &ipfr_block; 890 fin->fin_reason = FRB_BADFRAG; 891 } else { 892 fr = fra->ipfr_rule; 893 } 894 fin->fin_fr = fr; 895 if (fr != NULL) { 896 pass = fr->fr_flags; 897 if ((pass & FR_KEEPSTATE) != 0) { 898 fin->fin_flx |= FI_STATE; 899 /* 900 * Reset the keep state flag here so that we 901 * don't try and add a new state entry because 902 * of a match here. That leads to blocking of 903 * the packet later because the add fails. 904 */ 905 pass &= ~FR_KEEPSTATE; 906 } 907 if ((pass & FR_LOGFIRST) != 0) 908 pass &= ~(FR_LOGFIRST|FR_LOG); 909 *passp = pass; 910 } 911 RWLOCK_EXIT(&softc->ipf_frag); 912 } 913 return fr; 914 } 915 916 917 /* ------------------------------------------------------------------------ */ 918 /* Function: ipf_frag_natforget */ 919 /* Returns: Nil */ 920 /* Parameters: ptr(I) - pointer to data structure */ 921 /* */ 922 /* Search through all of the fragment cache entries for NAT and wherever a */ 923 /* pointer is found to match ptr, reset it to NULL. */ 924 /* ------------------------------------------------------------------------ */ 925 void 926 ipf_frag_natforget(ipf_main_softc_t *softc, void *ptr) 927 { 928 ipf_frag_softc_t *softf = softc->ipf_frag_soft; 929 ipfr_t *fr; 930 931 WRITE_ENTER(&softf->ipfr_natfrag); 932 for (fr = softf->ipfr_natlist; fr; fr = fr->ipfr_next) 933 if (fr->ipfr_data == ptr) 934 fr->ipfr_data = NULL; 935 RWLOCK_EXIT(&softf->ipfr_natfrag); 936 } 937 938 939 /* ------------------------------------------------------------------------ */ 940 /* Function: ipf_frag_delete */ 941 /* Returns: Nil */ 942 /* Parameters: fra(I) - pointer to fragment structure to delete */ 943 /* tail(IO) - pointer to the pointer to the tail of the frag */ 944 /* list */ 945 /* */ 946 /* Remove a fragment cache table entry from the table & list. Also free */ 947 /* the filter rule it is associated with it if it is no longer used as a */ 948 /* result of decreasing the reference count. */ 949 /* ------------------------------------------------------------------------ */ 950 static void 951 ipf_frag_delete(ipf_main_softc_t *softc, ipfr_t *fra, ipfr_t ***tail) 952 { 953 ipf_frag_softc_t *softf = softc->ipf_frag_soft; 954 955 if (fra->ipfr_next) 956 fra->ipfr_next->ipfr_prev = fra->ipfr_prev; 957 *fra->ipfr_prev = fra->ipfr_next; 958 if (*tail == &fra->ipfr_next) 959 *tail = fra->ipfr_prev; 960 961 if (fra->ipfr_hnext) 962 fra->ipfr_hnext->ipfr_hprev = fra->ipfr_hprev; 963 *fra->ipfr_hprev = fra->ipfr_hnext; 964 965 if (fra->ipfr_rule != NULL) { 966 (void) ipf_derefrule(softc, &fra->ipfr_rule); 967 } 968 969 if (fra->ipfr_ref <= 0) 970 ipf_frag_free(softf, fra); 971 } 972 973 974 /* ------------------------------------------------------------------------ */ 975 /* Function: ipf_frag_free */ 976 /* Returns: Nil */ 977 /* */ 978 /* ------------------------------------------------------------------------ */ 979 static void 980 ipf_frag_free(ipf_frag_softc_t *softf, ipfr_t *fra) 981 { 982 KFREE(fra); 983 FBUMP(ifs_expire); 984 softf->ipfr_stats.ifs_inuse--; 985 } 986 987 988 /* ------------------------------------------------------------------------ */ 989 /* Function: ipf_frag_clear */ 990 /* Returns: Nil */ 991 /* Parameters: Nil */ 992 /* */ 993 /* Free memory in use by fragment state information kept. Do the normal */ 994 /* fragment state stuff first and then the NAT-fragment table. */ 995 /* ------------------------------------------------------------------------ */ 996 void 997 ipf_frag_clear(ipf_main_softc_t *softc) 998 { 999 ipf_frag_softc_t *softf = softc->ipf_frag_soft; 1000 ipfr_t *fra; 1001 nat_t *nat; 1002 1003 WRITE_ENTER(&softc->ipf_frag); 1004 while ((fra = softf->ipfr_list) != NULL) { 1005 fra->ipfr_ref--; 1006 ipf_frag_delete(softc, fra, &softf->ipfr_tail); 1007 } 1008 softf->ipfr_tail = &softf->ipfr_list; 1009 RWLOCK_EXIT(&softc->ipf_frag); 1010 1011 WRITE_ENTER(&softc->ipf_nat); 1012 WRITE_ENTER(&softf->ipfr_natfrag); 1013 while ((fra = softf->ipfr_natlist) != NULL) { 1014 nat = fra->ipfr_data; 1015 if (nat != NULL) { 1016 if (nat->nat_data == fra) 1017 nat->nat_data = NULL; 1018 } 1019 fra->ipfr_ref--; 1020 ipf_frag_delete(softc, fra, &softf->ipfr_nattail); 1021 } 1022 softf->ipfr_nattail = &softf->ipfr_natlist; 1023 RWLOCK_EXIT(&softf->ipfr_natfrag); 1024 RWLOCK_EXIT(&softc->ipf_nat); 1025 } 1026 1027 1028 /* ------------------------------------------------------------------------ */ 1029 /* Function: ipf_frag_expire */ 1030 /* Returns: Nil */ 1031 /* Parameters: Nil */ 1032 /* */ 1033 /* Expire entries in the fragment cache table that have been there too long */ 1034 /* ------------------------------------------------------------------------ */ 1035 void 1036 ipf_frag_expire(ipf_main_softc_t *softc) 1037 { 1038 ipf_frag_softc_t *softf = softc->ipf_frag_soft; 1039 ipfr_t **fp, *fra; 1040 nat_t *nat; 1041 SPL_INT(s); 1042 1043 if (softf->ipfr_lock) 1044 return; 1045 1046 SPL_NET(s); 1047 WRITE_ENTER(&softc->ipf_frag); 1048 /* 1049 * Go through the entire table, looking for entries to expire, 1050 * which is indicated by the ttl being less than or equal to ipf_ticks. 1051 */ 1052 for (fp = &softf->ipfr_list; ((fra = *fp) != NULL); ) { 1053 if (fra->ipfr_ttl > softc->ipf_ticks) 1054 break; 1055 fra->ipfr_ref--; 1056 ipf_frag_delete(softc, fra, &softf->ipfr_tail); 1057 } 1058 RWLOCK_EXIT(&softc->ipf_frag); 1059 1060 WRITE_ENTER(&softf->ipfr_ipidfrag); 1061 for (fp = &softf->ipfr_ipidlist; ((fra = *fp) != NULL); ) { 1062 if (fra->ipfr_ttl > softc->ipf_ticks) 1063 break; 1064 fra->ipfr_ref--; 1065 ipf_frag_delete(softc, fra, &softf->ipfr_ipidtail); 1066 } 1067 RWLOCK_EXIT(&softf->ipfr_ipidfrag); 1068 1069 /* 1070 * Same again for the NAT table, except that if the structure also 1071 * still points to a NAT structure, and the NAT structure points back 1072 * at the one to be free'd, NULL the reference from the NAT struct. 1073 * NOTE: We need to grab both mutex's early, and in this order so as 1074 * to prevent a deadlock if both try to expire at the same time. 1075 * The extra if() statement here is because it locks out all NAT 1076 * operations - no need to do that if there are no entries in this 1077 * list, right? 1078 */ 1079 if (softf->ipfr_natlist != NULL) { 1080 WRITE_ENTER(&softc->ipf_nat); 1081 WRITE_ENTER(&softf->ipfr_natfrag); 1082 for (fp = &softf->ipfr_natlist; ((fra = *fp) != NULL); ) { 1083 if (fra->ipfr_ttl > softc->ipf_ticks) 1084 break; 1085 nat = fra->ipfr_data; 1086 if (nat != NULL) { 1087 if (nat->nat_data == fra) 1088 nat->nat_data = NULL; 1089 } 1090 fra->ipfr_ref--; 1091 ipf_frag_delete(softc, fra, &softf->ipfr_nattail); 1092 } 1093 RWLOCK_EXIT(&softf->ipfr_natfrag); 1094 RWLOCK_EXIT(&softc->ipf_nat); 1095 } 1096 SPL_X(s); 1097 } 1098 1099 1100 /* ------------------------------------------------------------------------ */ 1101 /* Function: ipf_frag_pkt_next */ 1102 /* ------------------------------------------------------------------------ */ 1103 int 1104 ipf_frag_pkt_next(ipf_main_softc_t *softc, ipftoken_t *token, ipfgeniter_t *itp) 1105 { 1106 ipf_frag_softc_t *softf = softc->ipf_frag_soft; 1107 1108 #ifdef USE_MUTEXES 1109 return ipf_frag_next(softc, token, itp, &softf->ipfr_list, 1110 &softf->ipfr_frag); 1111 #else 1112 return ipf_frag_next(softc, token, itp, &softf->ipfr_list); 1113 #endif 1114 } 1115 1116 1117 /* ------------------------------------------------------------------------ */ 1118 /* Function: ipf_frag_nat_next */ 1119 /* ------------------------------------------------------------------------ */ 1120 int 1121 ipf_frag_nat_next(ipf_main_softc_t *softc, ipftoken_t *token, ipfgeniter_t *itp) 1122 { 1123 ipf_frag_softc_t *softf = softc->ipf_frag_soft;; 1124 1125 #ifdef USE_MUTEXES 1126 return ipf_frag_next(softc, token, itp, &softf->ipfr_natlist, 1127 &softf->ipfr_natfrag); 1128 #else 1129 return ipf_frag_next(softc, token, itp, &softf->ipfr_natlist); 1130 #endif 1131 } 1132 1133 /* ------------------------------------------------------------------------ */ 1134 /* Function: ipf_frag_next */ 1135 /* Returns: int - 0 == success, else error */ 1136 /* Parameters: token(I) - pointer to token information for this caller */ 1137 /* itp(I) - pointer to generic iterator from caller */ 1138 /* top(I) - top of the fragment list */ 1139 /* lock(I) - fragment cache lock */ 1140 /* */ 1141 /* This function is used to interate through the list of entries in the */ 1142 /* fragment cache. It increases the reference count on the one currently */ 1143 /* being returned so that the caller can come back and resume from it later.*/ 1144 /* */ 1145 /* This function is used for both the NAT fragment cache as well as the ipf */ 1146 /* fragment cache - hence the reason for passing in top and lock. */ 1147 /* ------------------------------------------------------------------------ */ 1148 static int 1149 ipf_frag_next( 1150 ipf_main_softc_t *softc, 1151 ipftoken_t *token, 1152 ipfgeniter_t *itp, 1153 ipfr_t **top 1154 #ifdef USE_MUTEXES 1155 , ipfrwlock_t *lock 1156 #endif 1157 ) 1158 { 1159 ipfr_t *frag, *next, zero; 1160 int error = 0; 1161 1162 if (itp->igi_data == NULL) { 1163 IPFERROR(20001); 1164 return EFAULT; 1165 } 1166 1167 if (itp->igi_nitems != 1) { 1168 IPFERROR(20003); 1169 return EFAULT; 1170 } 1171 1172 frag = token->ipt_data; 1173 1174 READ_ENTER(lock); 1175 1176 if (frag == NULL) 1177 next = *top; 1178 else 1179 next = frag->ipfr_next; 1180 1181 if (next != NULL) { 1182 ATOMIC_INC(next->ipfr_ref); 1183 token->ipt_data = next; 1184 } else { 1185 bzero(&zero, sizeof(zero)); 1186 next = &zero; 1187 token->ipt_data = NULL; 1188 } 1189 if (next->ipfr_next == NULL) 1190 ipf_token_mark_complete(token); 1191 1192 RWLOCK_EXIT(lock); 1193 1194 error = COPYOUT(next, itp->igi_data, sizeof(*next)); 1195 if (error != 0) 1196 IPFERROR(20002); 1197 1198 if (frag != NULL) { 1199 #ifdef USE_MUTEXES 1200 ipf_frag_deref(softc, &frag, lock); 1201 #else 1202 ipf_frag_deref(softc, &frag); 1203 #endif 1204 } 1205 return error; 1206 } 1207 1208 1209 /* ------------------------------------------------------------------------ */ 1210 /* Function: ipf_frag_pkt_deref */ 1211 /* Returns: Nil */ 1212 /* */ 1213 /* ------------------------------------------------------------------------ */ 1214 void 1215 ipf_frag_pkt_deref(ipf_main_softc_t *softc, void *data) 1216 { 1217 ipfr_t **frp = data; 1218 1219 #ifdef USE_MUTEXES 1220 ipf_frag_softc_t *softf = softc->ipf_frag_soft; 1221 1222 ipf_frag_deref(softc->ipf_frag_soft, frp, &softf->ipfr_frag); 1223 #else 1224 ipf_frag_deref(softc->ipf_frag_soft, frp); 1225 #endif 1226 } 1227 1228 1229 /* ------------------------------------------------------------------------ */ 1230 /* Function: ipf_frag_nat_deref */ 1231 /* Returns: Nil */ 1232 /* */ 1233 /* ------------------------------------------------------------------------ */ 1234 void 1235 ipf_frag_nat_deref(ipf_main_softc_t *softc, void *data) 1236 { 1237 ipfr_t **frp = data; 1238 1239 #ifdef USE_MUTEXES 1240 ipf_frag_softc_t *softf = softc->ipf_frag_soft; 1241 1242 ipf_frag_deref(softc->ipf_frag_soft, frp, &softf->ipfr_natfrag); 1243 #else 1244 ipf_frag_deref(softc->ipf_frag_soft, frp); 1245 #endif 1246 } 1247 1248 1249 /* ------------------------------------------------------------------------ */ 1250 /* Function: ipf_frag_deref */ 1251 /* Returns: Nil */ 1252 /* Parameters: frp(IO) - pointer to fragment structure to deference */ 1253 /* lock(I) - lock associated with the fragment */ 1254 /* */ 1255 /* This function dereferences a fragment structure (ipfr_t). The pointer */ 1256 /* passed in will always be reset back to NULL, even if the structure is */ 1257 /* not freed, to enforce the notion that the caller is no longer entitled */ 1258 /* to use the pointer it is dropping the reference to. */ 1259 /* ------------------------------------------------------------------------ */ 1260 static void 1261 ipf_frag_deref(void *arg, ipfr_t **frp 1262 #ifdef USE_MUTEXES 1263 , ipfrwlock_t *lock 1264 #endif 1265 ) 1266 { 1267 ipf_frag_softc_t *softf = arg; 1268 ipfr_t *fra; 1269 1270 fra = *frp; 1271 *frp = NULL; 1272 1273 WRITE_ENTER(lock); 1274 fra->ipfr_ref--; 1275 if (fra->ipfr_ref <= 0) 1276 ipf_frag_free(softf, fra); 1277 RWLOCK_EXIT(lock); 1278 } 1279
Indexes created Wed Oct 15 16:09:53 GMT 2025