nf_conntrack_core.c revision 9858a3ae1d4b390fbaa9c30b83cb66d861b76294
1/* Connection state tracking for netfilter. This is separated from, 2 but required by, the NAT layer; it can also be used by an iptables 3 extension. */ 4 5/* (C) 1999-2001 Paul `Rusty' Russell 6 * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org> 7 * (C) 2003,2004 USAGI/WIDE Project <http://www.linux-ipv6.org> 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License version 2 as 11 * published by the Free Software Foundation. 12 */ 13 14#include <linux/types.h> 15#include <linux/netfilter.h> 16#include <linux/module.h> 17#include <linux/skbuff.h> 18#include <linux/proc_fs.h> 19#include <linux/vmalloc.h> 20#include <linux/stddef.h> 21#include <linux/slab.h> 22#include <linux/random.h> 23#include <linux/jhash.h> 24#include <linux/err.h> 25#include <linux/percpu.h> 26#include <linux/moduleparam.h> 27#include <linux/notifier.h> 28#include <linux/kernel.h> 29#include <linux/netdevice.h> 30#include <linux/socket.h> 31#include <linux/mm.h> 32#include <linux/rculist_nulls.h> 33 34#include <net/netfilter/nf_conntrack.h> 35#include <net/netfilter/nf_conntrack_l3proto.h> 36#include <net/netfilter/nf_conntrack_l4proto.h> 37#include <net/netfilter/nf_conntrack_expect.h> 38#include <net/netfilter/nf_conntrack_helper.h> 39#include <net/netfilter/nf_conntrack_core.h> 40#include <net/netfilter/nf_conntrack_extend.h> 41#include <net/netfilter/nf_conntrack_acct.h> 42#include <net/netfilter/nf_conntrack_ecache.h> 43#include <net/netfilter/nf_nat.h> 44#include <net/netfilter/nf_nat_core.h> 45 46#define NF_CONNTRACK_VERSION "0.5.0" 47 48int (*nfnetlink_parse_nat_setup_hook)(struct nf_conn *ct, 49 enum nf_nat_manip_type manip, 50 struct nlattr *attr) __read_mostly; 51EXPORT_SYMBOL_GPL(nfnetlink_parse_nat_setup_hook); 52 53DEFINE_SPINLOCK(nf_conntrack_lock); 54EXPORT_SYMBOL_GPL(nf_conntrack_lock); 55 56unsigned int nf_conntrack_htable_size __read_mostly; 57EXPORT_SYMBOL_GPL(nf_conntrack_htable_size); 58 59unsigned int nf_conntrack_max __read_mostly; 60EXPORT_SYMBOL_GPL(nf_conntrack_max); 61 62struct nf_conn nf_conntrack_untracked __read_mostly; 63EXPORT_SYMBOL_GPL(nf_conntrack_untracked); 64 65static struct kmem_cache *nf_conntrack_cachep __read_mostly; 66 67static int nf_conntrack_hash_rnd_initted; 68static unsigned int nf_conntrack_hash_rnd; 69 70static u_int32_t __hash_conntrack(const struct nf_conntrack_tuple *tuple, 71 unsigned int size, unsigned int rnd) 72{ 73 unsigned int n; 74 u_int32_t h; 75 76 /* The direction must be ignored, so we hash everything up to the 77 * destination ports (which is a multiple of 4) and treat the last 78 * three bytes manually. 79 */ 80 n = (sizeof(tuple->src) + sizeof(tuple->dst.u3)) / sizeof(u32); 81 h = jhash2((u32 *)tuple, n, 82 rnd ^ (((__force __u16)tuple->dst.u.all << 16) | 83 tuple->dst.protonum)); 84 85 return ((u64)h * size) >> 32; 86} 87 88static inline u_int32_t hash_conntrack(const struct nf_conntrack_tuple *tuple) 89{ 90 return __hash_conntrack(tuple, nf_conntrack_htable_size, 91 nf_conntrack_hash_rnd); 92} 93 94bool 95nf_ct_get_tuple(const struct sk_buff *skb, 96 unsigned int nhoff, 97 unsigned int dataoff, 98 u_int16_t l3num, 99 u_int8_t protonum, 100 struct nf_conntrack_tuple *tuple, 101 const struct nf_conntrack_l3proto *l3proto, 102 const struct nf_conntrack_l4proto *l4proto) 103{ 104 memset(tuple, 0, sizeof(*tuple)); 105 106 tuple->src.l3num = l3num; 107 if (l3proto->pkt_to_tuple(skb, nhoff, tuple) == 0) 108 return false; 109 110 tuple->dst.protonum = protonum; 111 tuple->dst.dir = IP_CT_DIR_ORIGINAL; 112 113 return l4proto->pkt_to_tuple(skb, dataoff, tuple); 114} 115EXPORT_SYMBOL_GPL(nf_ct_get_tuple); 116 117bool nf_ct_get_tuplepr(const struct sk_buff *skb, unsigned int nhoff, 118 u_int16_t l3num, struct nf_conntrack_tuple *tuple) 119{ 120 struct nf_conntrack_l3proto *l3proto; 121 struct nf_conntrack_l4proto *l4proto; 122 unsigned int protoff; 123 u_int8_t protonum; 124 int ret; 125 126 rcu_read_lock(); 127 128 l3proto = __nf_ct_l3proto_find(l3num); 129 ret = l3proto->get_l4proto(skb, nhoff, &protoff, &protonum); 130 if (ret != NF_ACCEPT) { 131 rcu_read_unlock(); 132 return false; 133 } 134 135 l4proto = __nf_ct_l4proto_find(l3num, protonum); 136 137 ret = nf_ct_get_tuple(skb, nhoff, protoff, l3num, protonum, tuple, 138 l3proto, l4proto); 139 140 rcu_read_unlock(); 141 return ret; 142} 143EXPORT_SYMBOL_GPL(nf_ct_get_tuplepr); 144 145bool 146nf_ct_invert_tuple(struct nf_conntrack_tuple *inverse, 147 const struct nf_conntrack_tuple *orig, 148 const struct nf_conntrack_l3proto *l3proto, 149 const struct nf_conntrack_l4proto *l4proto) 150{ 151 memset(inverse, 0, sizeof(*inverse)); 152 153 inverse->src.l3num = orig->src.l3num; 154 if (l3proto->invert_tuple(inverse, orig) == 0) 155 return false; 156 157 inverse->dst.dir = !orig->dst.dir; 158 159 inverse->dst.protonum = orig->dst.protonum; 160 return l4proto->invert_tuple(inverse, orig); 161} 162EXPORT_SYMBOL_GPL(nf_ct_invert_tuple); 163 164static void 165clean_from_lists(struct nf_conn *ct) 166{ 167 pr_debug("clean_from_lists(%p)\n", ct); 168 hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode); 169 hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_REPLY].hnnode); 170 171 /* Destroy all pending expectations */ 172 nf_ct_remove_expectations(ct); 173} 174 175static void 176destroy_conntrack(struct nf_conntrack *nfct) 177{ 178 struct nf_conn *ct = (struct nf_conn *)nfct; 179 struct net *net = nf_ct_net(ct); 180 struct nf_conntrack_l4proto *l4proto; 181 182 pr_debug("destroy_conntrack(%p)\n", ct); 183 NF_CT_ASSERT(atomic_read(&nfct->use) == 0); 184 NF_CT_ASSERT(!timer_pending(&ct->timeout)); 185 186 if (!test_bit(IPS_DYING_BIT, &ct->status)) 187 nf_conntrack_event(IPCT_DESTROY, ct); 188 set_bit(IPS_DYING_BIT, &ct->status); 189 190 /* To make sure we don't get any weird locking issues here: 191 * destroy_conntrack() MUST NOT be called with a write lock 192 * to nf_conntrack_lock!!! -HW */ 193 rcu_read_lock(); 194 l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct)); 195 if (l4proto && l4proto->destroy) 196 l4proto->destroy(ct); 197 198 rcu_read_unlock(); 199 200 spin_lock_bh(&nf_conntrack_lock); 201 /* Expectations will have been removed in clean_from_lists, 202 * except TFTP can create an expectation on the first packet, 203 * before connection is in the list, so we need to clean here, 204 * too. */ 205 nf_ct_remove_expectations(ct); 206 207 /* We overload first tuple to link into unconfirmed list. */ 208 if (!nf_ct_is_confirmed(ct)) { 209 BUG_ON(hlist_nulls_unhashed(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode)); 210 hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode); 211 } 212 213 NF_CT_STAT_INC(net, delete); 214 spin_unlock_bh(&nf_conntrack_lock); 215 216 if (ct->master) 217 nf_ct_put(ct->master); 218 219 pr_debug("destroy_conntrack: returning ct=%p to slab\n", ct); 220 nf_conntrack_free(ct); 221} 222 223static void death_by_timeout(unsigned long ul_conntrack) 224{ 225 struct nf_conn *ct = (void *)ul_conntrack; 226 struct net *net = nf_ct_net(ct); 227 228 nf_ct_helper_destroy(ct); 229 spin_lock_bh(&nf_conntrack_lock); 230 /* Inside lock so preempt is disabled on module removal path. 231 * Otherwise we can get spurious warnings. */ 232 NF_CT_STAT_INC(net, delete_list); 233 clean_from_lists(ct); 234 spin_unlock_bh(&nf_conntrack_lock); 235 nf_ct_put(ct); 236} 237 238/* 239 * Warning : 240 * - Caller must take a reference on returned object 241 * and recheck nf_ct_tuple_equal(tuple, &h->tuple) 242 * OR 243 * - Caller must lock nf_conntrack_lock before calling this function 244 */ 245struct nf_conntrack_tuple_hash * 246__nf_conntrack_find(struct net *net, const struct nf_conntrack_tuple *tuple) 247{ 248 struct nf_conntrack_tuple_hash *h; 249 struct hlist_nulls_node *n; 250 unsigned int hash = hash_conntrack(tuple); 251 252 /* Disable BHs the entire time since we normally need to disable them 253 * at least once for the stats anyway. 254 */ 255 local_bh_disable(); 256begin: 257 hlist_nulls_for_each_entry_rcu(h, n, &net->ct.hash[hash], hnnode) { 258 if (nf_ct_tuple_equal(tuple, &h->tuple)) { 259 NF_CT_STAT_INC(net, found); 260 local_bh_enable(); 261 return h; 262 } 263 NF_CT_STAT_INC(net, searched); 264 } 265 /* 266 * if the nulls value we got at the end of this lookup is 267 * not the expected one, we must restart lookup. 268 * We probably met an item that was moved to another chain. 269 */ 270 if (get_nulls_value(n) != hash) 271 goto begin; 272 local_bh_enable(); 273 274 return NULL; 275} 276EXPORT_SYMBOL_GPL(__nf_conntrack_find); 277 278/* Find a connection corresponding to a tuple. */ 279struct nf_conntrack_tuple_hash * 280nf_conntrack_find_get(struct net *net, const struct nf_conntrack_tuple *tuple) 281{ 282 struct nf_conntrack_tuple_hash *h; 283 struct nf_conn *ct; 284 285 rcu_read_lock(); 286begin: 287 h = __nf_conntrack_find(net, tuple); 288 if (h) { 289 ct = nf_ct_tuplehash_to_ctrack(h); 290 if (unlikely(!atomic_inc_not_zero(&ct->ct_general.use))) 291 h = NULL; 292 else { 293 if (unlikely(!nf_ct_tuple_equal(tuple, &h->tuple))) { 294 nf_ct_put(ct); 295 goto begin; 296 } 297 } 298 } 299 rcu_read_unlock(); 300 301 return h; 302} 303EXPORT_SYMBOL_GPL(nf_conntrack_find_get); 304 305static void __nf_conntrack_hash_insert(struct nf_conn *ct, 306 unsigned int hash, 307 unsigned int repl_hash) 308{ 309 struct net *net = nf_ct_net(ct); 310 311 hlist_nulls_add_head_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode, 312 &net->ct.hash[hash]); 313 hlist_nulls_add_head_rcu(&ct->tuplehash[IP_CT_DIR_REPLY].hnnode, 314 &net->ct.hash[repl_hash]); 315} 316 317void nf_conntrack_hash_insert(struct nf_conn *ct) 318{ 319 unsigned int hash, repl_hash; 320 321 hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); 322 repl_hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_REPLY].tuple); 323 324 __nf_conntrack_hash_insert(ct, hash, repl_hash); 325} 326EXPORT_SYMBOL_GPL(nf_conntrack_hash_insert); 327 328/* Confirm a connection given skb; places it in hash table */ 329int 330__nf_conntrack_confirm(struct sk_buff *skb) 331{ 332 unsigned int hash, repl_hash; 333 struct nf_conntrack_tuple_hash *h; 334 struct nf_conn *ct; 335 struct nf_conn_help *help; 336 struct hlist_nulls_node *n; 337 enum ip_conntrack_info ctinfo; 338 struct net *net; 339 340 ct = nf_ct_get(skb, &ctinfo); 341 net = nf_ct_net(ct); 342 343 /* ipt_REJECT uses nf_conntrack_attach to attach related 344 ICMP/TCP RST packets in other direction. Actual packet 345 which created connection will be IP_CT_NEW or for an 346 expected connection, IP_CT_RELATED. */ 347 if (CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) 348 return NF_ACCEPT; 349 350 hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); 351 repl_hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_REPLY].tuple); 352 353 /* We're not in hash table, and we refuse to set up related 354 connections for unconfirmed conns. But packet copies and 355 REJECT will give spurious warnings here. */ 356 /* NF_CT_ASSERT(atomic_read(&ct->ct_general.use) == 1); */ 357 358 /* No external references means noone else could have 359 confirmed us. */ 360 NF_CT_ASSERT(!nf_ct_is_confirmed(ct)); 361 pr_debug("Confirming conntrack %p\n", ct); 362 363 spin_lock_bh(&nf_conntrack_lock); 364 365 /* See if there's one in the list already, including reverse: 366 NAT could have grabbed it without realizing, since we're 367 not in the hash. If there is, we lost race. */ 368 hlist_nulls_for_each_entry(h, n, &net->ct.hash[hash], hnnode) 369 if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple, 370 &h->tuple)) 371 goto out; 372 hlist_nulls_for_each_entry(h, n, &net->ct.hash[repl_hash], hnnode) 373 if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_REPLY].tuple, 374 &h->tuple)) 375 goto out; 376 377 /* Remove from unconfirmed list */ 378 hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode); 379 380 __nf_conntrack_hash_insert(ct, hash, repl_hash); 381 /* Timer relative to confirmation time, not original 382 setting time, otherwise we'd get timer wrap in 383 weird delay cases. */ 384 ct->timeout.expires += jiffies; 385 add_timer(&ct->timeout); 386 atomic_inc(&ct->ct_general.use); 387 set_bit(IPS_CONFIRMED_BIT, &ct->status); 388 NF_CT_STAT_INC(net, insert); 389 spin_unlock_bh(&nf_conntrack_lock); 390 help = nfct_help(ct); 391 if (help && help->helper) 392 nf_conntrack_event_cache(IPCT_HELPER, ct); 393 394 nf_conntrack_event_cache(master_ct(ct) ? 395 IPCT_RELATED : IPCT_NEW, ct); 396 return NF_ACCEPT; 397 398out: 399 NF_CT_STAT_INC(net, insert_failed); 400 spin_unlock_bh(&nf_conntrack_lock); 401 return NF_DROP; 402} 403EXPORT_SYMBOL_GPL(__nf_conntrack_confirm); 404 405/* Returns true if a connection correspondings to the tuple (required 406 for NAT). */ 407int 408nf_conntrack_tuple_taken(const struct nf_conntrack_tuple *tuple, 409 const struct nf_conn *ignored_conntrack) 410{ 411 struct net *net = nf_ct_net(ignored_conntrack); 412 struct nf_conntrack_tuple_hash *h; 413 struct hlist_nulls_node *n; 414 unsigned int hash = hash_conntrack(tuple); 415 416 /* Disable BHs the entire time since we need to disable them at 417 * least once for the stats anyway. 418 */ 419 rcu_read_lock_bh(); 420 hlist_nulls_for_each_entry_rcu(h, n, &net->ct.hash[hash], hnnode) { 421 if (nf_ct_tuplehash_to_ctrack(h) != ignored_conntrack && 422 nf_ct_tuple_equal(tuple, &h->tuple)) { 423 NF_CT_STAT_INC(net, found); 424 rcu_read_unlock_bh(); 425 return 1; 426 } 427 NF_CT_STAT_INC(net, searched); 428 } 429 rcu_read_unlock_bh(); 430 431 return 0; 432} 433EXPORT_SYMBOL_GPL(nf_conntrack_tuple_taken); 434 435#define NF_CT_EVICTION_RANGE 8 436 437/* There's a small race here where we may free a just-assured 438 connection. Too bad: we're in trouble anyway. */ 439static noinline int early_drop(struct net *net, unsigned int hash) 440{ 441 /* Use oldest entry, which is roughly LRU */ 442 struct nf_conntrack_tuple_hash *h; 443 struct nf_conn *ct = NULL, *tmp; 444 struct hlist_nulls_node *n; 445 unsigned int i, cnt = 0; 446 int dropped = 0; 447 448 rcu_read_lock(); 449 for (i = 0; i < nf_conntrack_htable_size; i++) { 450 hlist_nulls_for_each_entry_rcu(h, n, &net->ct.hash[hash], 451 hnnode) { 452 tmp = nf_ct_tuplehash_to_ctrack(h); 453 if (!test_bit(IPS_ASSURED_BIT, &tmp->status)) 454 ct = tmp; 455 cnt++; 456 } 457 458 if (ct && unlikely(!atomic_inc_not_zero(&ct->ct_general.use))) 459 ct = NULL; 460 if (ct || cnt >= NF_CT_EVICTION_RANGE) 461 break; 462 hash = (hash + 1) % nf_conntrack_htable_size; 463 } 464 rcu_read_unlock(); 465 466 if (!ct) 467 return dropped; 468 469 if (del_timer(&ct->timeout)) { 470 death_by_timeout((unsigned long)ct); 471 dropped = 1; 472 NF_CT_STAT_INC_ATOMIC(net, early_drop); 473 } 474 nf_ct_put(ct); 475 return dropped; 476} 477 478struct nf_conn *nf_conntrack_alloc(struct net *net, 479 const struct nf_conntrack_tuple *orig, 480 const struct nf_conntrack_tuple *repl, 481 gfp_t gfp) 482{ 483 struct nf_conn *ct; 484 485 if (unlikely(!nf_conntrack_hash_rnd_initted)) { 486 get_random_bytes(&nf_conntrack_hash_rnd, 487 sizeof(nf_conntrack_hash_rnd)); 488 nf_conntrack_hash_rnd_initted = 1; 489 } 490 491 /* We don't want any race condition at early drop stage */ 492 atomic_inc(&net->ct.count); 493 494 if (nf_conntrack_max && 495 unlikely(atomic_read(&net->ct.count) > nf_conntrack_max)) { 496 unsigned int hash = hash_conntrack(orig); 497 if (!early_drop(net, hash)) { 498 atomic_dec(&net->ct.count); 499 if (net_ratelimit()) 500 printk(KERN_WARNING 501 "nf_conntrack: table full, dropping" 502 " packet.\n"); 503 return ERR_PTR(-ENOMEM); 504 } 505 } 506 507 ct = kmem_cache_zalloc(nf_conntrack_cachep, gfp); 508 if (ct == NULL) { 509 pr_debug("nf_conntrack_alloc: Can't alloc conntrack.\n"); 510 atomic_dec(&net->ct.count); 511 return ERR_PTR(-ENOMEM); 512 } 513 514 spin_lock_init(&ct->lock); 515 atomic_set(&ct->ct_general.use, 1); 516 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple = *orig; 517 ct->tuplehash[IP_CT_DIR_REPLY].tuple = *repl; 518 /* Don't set timer yet: wait for confirmation */ 519 setup_timer(&ct->timeout, death_by_timeout, (unsigned long)ct); 520#ifdef CONFIG_NET_NS 521 ct->ct_net = net; 522#endif 523 524 return ct; 525} 526EXPORT_SYMBOL_GPL(nf_conntrack_alloc); 527 528void nf_conntrack_free(struct nf_conn *ct) 529{ 530 struct net *net = nf_ct_net(ct); 531 532 nf_ct_ext_destroy(ct); 533 atomic_dec(&net->ct.count); 534 nf_ct_ext_free(ct); 535 kmem_cache_free(nf_conntrack_cachep, ct); 536} 537EXPORT_SYMBOL_GPL(nf_conntrack_free); 538 539/* Allocate a new conntrack: we return -ENOMEM if classification 540 failed due to stress. Otherwise it really is unclassifiable. */ 541static struct nf_conntrack_tuple_hash * 542init_conntrack(struct net *net, 543 const struct nf_conntrack_tuple *tuple, 544 struct nf_conntrack_l3proto *l3proto, 545 struct nf_conntrack_l4proto *l4proto, 546 struct sk_buff *skb, 547 unsigned int dataoff) 548{ 549 struct nf_conn *ct; 550 struct nf_conn_help *help; 551 struct nf_conntrack_tuple repl_tuple; 552 struct nf_conntrack_expect *exp; 553 554 if (!nf_ct_invert_tuple(&repl_tuple, tuple, l3proto, l4proto)) { 555 pr_debug("Can't invert tuple.\n"); 556 return NULL; 557 } 558 559 ct = nf_conntrack_alloc(net, tuple, &repl_tuple, GFP_ATOMIC); 560 if (IS_ERR(ct)) { 561 pr_debug("Can't allocate conntrack.\n"); 562 return (struct nf_conntrack_tuple_hash *)ct; 563 } 564 565 if (!l4proto->new(ct, skb, dataoff)) { 566 nf_conntrack_free(ct); 567 pr_debug("init conntrack: can't track with proto module\n"); 568 return NULL; 569 } 570 571 nf_ct_acct_ext_add(ct, GFP_ATOMIC); 572 nf_ct_ecache_ext_add(ct, GFP_ATOMIC); 573 574 spin_lock_bh(&nf_conntrack_lock); 575 exp = nf_ct_find_expectation(net, tuple); 576 if (exp) { 577 pr_debug("conntrack: expectation arrives ct=%p exp=%p\n", 578 ct, exp); 579 /* Welcome, Mr. Bond. We've been expecting you... */ 580 __set_bit(IPS_EXPECTED_BIT, &ct->status); 581 ct->master = exp->master; 582 if (exp->helper) { 583 help = nf_ct_helper_ext_add(ct, GFP_ATOMIC); 584 if (help) 585 rcu_assign_pointer(help->helper, exp->helper); 586 } 587 588#ifdef CONFIG_NF_CONNTRACK_MARK 589 ct->mark = exp->master->mark; 590#endif 591#ifdef CONFIG_NF_CONNTRACK_SECMARK 592 ct->secmark = exp->master->secmark; 593#endif 594 nf_conntrack_get(&ct->master->ct_general); 595 NF_CT_STAT_INC(net, expect_new); 596 } else { 597 __nf_ct_try_assign_helper(ct, GFP_ATOMIC); 598 NF_CT_STAT_INC(net, new); 599 } 600 601 /* Overload tuple linked list to put us in unconfirmed list. */ 602 hlist_nulls_add_head_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode, 603 &net->ct.unconfirmed); 604 605 spin_unlock_bh(&nf_conntrack_lock); 606 607 if (exp) { 608 if (exp->expectfn) 609 exp->expectfn(ct, exp); 610 nf_ct_expect_put(exp); 611 } 612 613 return &ct->tuplehash[IP_CT_DIR_ORIGINAL]; 614} 615 616/* On success, returns conntrack ptr, sets skb->nfct and ctinfo */ 617static inline struct nf_conn * 618resolve_normal_ct(struct net *net, 619 struct sk_buff *skb, 620 unsigned int dataoff, 621 u_int16_t l3num, 622 u_int8_t protonum, 623 struct nf_conntrack_l3proto *l3proto, 624 struct nf_conntrack_l4proto *l4proto, 625 int *set_reply, 626 enum ip_conntrack_info *ctinfo) 627{ 628 struct nf_conntrack_tuple tuple; 629 struct nf_conntrack_tuple_hash *h; 630 struct nf_conn *ct; 631 632 if (!nf_ct_get_tuple(skb, skb_network_offset(skb), 633 dataoff, l3num, protonum, &tuple, l3proto, 634 l4proto)) { 635 pr_debug("resolve_normal_ct: Can't get tuple\n"); 636 return NULL; 637 } 638 639 /* look for tuple match */ 640 h = nf_conntrack_find_get(net, &tuple); 641 if (!h) { 642 h = init_conntrack(net, &tuple, l3proto, l4proto, skb, dataoff); 643 if (!h) 644 return NULL; 645 if (IS_ERR(h)) 646 return (void *)h; 647 } 648 ct = nf_ct_tuplehash_to_ctrack(h); 649 650 /* It exists; we have (non-exclusive) reference. */ 651 if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) { 652 *ctinfo = IP_CT_ESTABLISHED + IP_CT_IS_REPLY; 653 /* Please set reply bit if this packet OK */ 654 *set_reply = 1; 655 } else { 656 /* Once we've had two way comms, always ESTABLISHED. */ 657 if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) { 658 pr_debug("nf_conntrack_in: normal packet for %p\n", ct); 659 *ctinfo = IP_CT_ESTABLISHED; 660 } else if (test_bit(IPS_EXPECTED_BIT, &ct->status)) { 661 pr_debug("nf_conntrack_in: related packet for %p\n", 662 ct); 663 *ctinfo = IP_CT_RELATED; 664 } else { 665 pr_debug("nf_conntrack_in: new packet for %p\n", ct); 666 *ctinfo = IP_CT_NEW; 667 } 668 *set_reply = 0; 669 } 670 skb->nfct = &ct->ct_general; 671 skb->nfctinfo = *ctinfo; 672 return ct; 673} 674 675unsigned int 676nf_conntrack_in(struct net *net, u_int8_t pf, unsigned int hooknum, 677 struct sk_buff *skb) 678{ 679 struct nf_conn *ct; 680 enum ip_conntrack_info ctinfo; 681 struct nf_conntrack_l3proto *l3proto; 682 struct nf_conntrack_l4proto *l4proto; 683 unsigned int dataoff; 684 u_int8_t protonum; 685 int set_reply = 0; 686 int ret; 687 688 /* Previously seen (loopback or untracked)? Ignore. */ 689 if (skb->nfct) { 690 NF_CT_STAT_INC_ATOMIC(net, ignore); 691 return NF_ACCEPT; 692 } 693 694 /* rcu_read_lock()ed by nf_hook_slow */ 695 l3proto = __nf_ct_l3proto_find(pf); 696 ret = l3proto->get_l4proto(skb, skb_network_offset(skb), 697 &dataoff, &protonum); 698 if (ret <= 0) { 699 pr_debug("not prepared to track yet or error occured\n"); 700 NF_CT_STAT_INC_ATOMIC(net, error); 701 NF_CT_STAT_INC_ATOMIC(net, invalid); 702 return -ret; 703 } 704 705 l4proto = __nf_ct_l4proto_find(pf, protonum); 706 707 /* It may be an special packet, error, unclean... 708 * inverse of the return code tells to the netfilter 709 * core what to do with the packet. */ 710 if (l4proto->error != NULL) { 711 ret = l4proto->error(net, skb, dataoff, &ctinfo, pf, hooknum); 712 if (ret <= 0) { 713 NF_CT_STAT_INC_ATOMIC(net, error); 714 NF_CT_STAT_INC_ATOMIC(net, invalid); 715 return -ret; 716 } 717 } 718 719 ct = resolve_normal_ct(net, skb, dataoff, pf, protonum, 720 l3proto, l4proto, &set_reply, &ctinfo); 721 if (!ct) { 722 /* Not valid part of a connection */ 723 NF_CT_STAT_INC_ATOMIC(net, invalid); 724 return NF_ACCEPT; 725 } 726 727 if (IS_ERR(ct)) { 728 /* Too stressed to deal. */ 729 NF_CT_STAT_INC_ATOMIC(net, drop); 730 return NF_DROP; 731 } 732 733 NF_CT_ASSERT(skb->nfct); 734 735 ret = l4proto->packet(ct, skb, dataoff, ctinfo, pf, hooknum); 736 if (ret <= 0) { 737 /* Invalid: inverse of the return code tells 738 * the netfilter core what to do */ 739 pr_debug("nf_conntrack_in: Can't track with proto module\n"); 740 nf_conntrack_put(skb->nfct); 741 skb->nfct = NULL; 742 NF_CT_STAT_INC_ATOMIC(net, invalid); 743 if (ret == -NF_DROP) 744 NF_CT_STAT_INC_ATOMIC(net, drop); 745 return -ret; 746 } 747 748 if (set_reply && !test_and_set_bit(IPS_SEEN_REPLY_BIT, &ct->status)) 749 nf_conntrack_event_cache(IPCT_STATUS, ct); 750 751 return ret; 752} 753EXPORT_SYMBOL_GPL(nf_conntrack_in); 754 755bool nf_ct_invert_tuplepr(struct nf_conntrack_tuple *inverse, 756 const struct nf_conntrack_tuple *orig) 757{ 758 bool ret; 759 760 rcu_read_lock(); 761 ret = nf_ct_invert_tuple(inverse, orig, 762 __nf_ct_l3proto_find(orig->src.l3num), 763 __nf_ct_l4proto_find(orig->src.l3num, 764 orig->dst.protonum)); 765 rcu_read_unlock(); 766 return ret; 767} 768EXPORT_SYMBOL_GPL(nf_ct_invert_tuplepr); 769 770/* Alter reply tuple (maybe alter helper). This is for NAT, and is 771 implicitly racy: see __nf_conntrack_confirm */ 772void nf_conntrack_alter_reply(struct nf_conn *ct, 773 const struct nf_conntrack_tuple *newreply) 774{ 775 struct nf_conn_help *help = nfct_help(ct); 776 777 /* Should be unconfirmed, so not in hash table yet */ 778 NF_CT_ASSERT(!nf_ct_is_confirmed(ct)); 779 780 pr_debug("Altering reply tuple of %p to ", ct); 781 nf_ct_dump_tuple(newreply); 782 783 ct->tuplehash[IP_CT_DIR_REPLY].tuple = *newreply; 784 if (ct->master || (help && !hlist_empty(&help->expectations))) 785 return; 786 787 rcu_read_lock(); 788 __nf_ct_try_assign_helper(ct, GFP_ATOMIC); 789 rcu_read_unlock(); 790} 791EXPORT_SYMBOL_GPL(nf_conntrack_alter_reply); 792 793/* Refresh conntrack for this many jiffies and do accounting if do_acct is 1 */ 794void __nf_ct_refresh_acct(struct nf_conn *ct, 795 enum ip_conntrack_info ctinfo, 796 const struct sk_buff *skb, 797 unsigned long extra_jiffies, 798 int do_acct) 799{ 800 NF_CT_ASSERT(ct->timeout.data == (unsigned long)ct); 801 NF_CT_ASSERT(skb); 802 803 /* Only update if this is not a fixed timeout */ 804 if (test_bit(IPS_FIXED_TIMEOUT_BIT, &ct->status)) 805 goto acct; 806 807 /* If not in hash table, timer will not be active yet */ 808 if (!nf_ct_is_confirmed(ct)) { 809 ct->timeout.expires = extra_jiffies; 810 } else { 811 unsigned long newtime = jiffies + extra_jiffies; 812 813 /* Only update the timeout if the new timeout is at least 814 HZ jiffies from the old timeout. Need del_timer for race 815 avoidance (may already be dying). */ 816 if (newtime - ct->timeout.expires >= HZ) 817 mod_timer_pending(&ct->timeout, newtime); 818 } 819 820acct: 821 if (do_acct) { 822 struct nf_conn_counter *acct; 823 824 acct = nf_conn_acct_find(ct); 825 if (acct) { 826 spin_lock_bh(&ct->lock); 827 acct[CTINFO2DIR(ctinfo)].packets++; 828 acct[CTINFO2DIR(ctinfo)].bytes += 829 skb->len - skb_network_offset(skb); 830 spin_unlock_bh(&ct->lock); 831 } 832 } 833} 834EXPORT_SYMBOL_GPL(__nf_ct_refresh_acct); 835 836bool __nf_ct_kill_acct(struct nf_conn *ct, 837 enum ip_conntrack_info ctinfo, 838 const struct sk_buff *skb, 839 int do_acct) 840{ 841 if (do_acct) { 842 struct nf_conn_counter *acct; 843 844 acct = nf_conn_acct_find(ct); 845 if (acct) { 846 spin_lock_bh(&ct->lock); 847 acct[CTINFO2DIR(ctinfo)].packets++; 848 acct[CTINFO2DIR(ctinfo)].bytes += 849 skb->len - skb_network_offset(skb); 850 spin_unlock_bh(&ct->lock); 851 } 852 } 853 854 if (del_timer(&ct->timeout)) { 855 ct->timeout.function((unsigned long)ct); 856 return true; 857 } 858 return false; 859} 860EXPORT_SYMBOL_GPL(__nf_ct_kill_acct); 861 862#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE) 863 864#include <linux/netfilter/nfnetlink.h> 865#include <linux/netfilter/nfnetlink_conntrack.h> 866#include <linux/mutex.h> 867 868/* Generic function for tcp/udp/sctp/dccp and alike. This needs to be 869 * in ip_conntrack_core, since we don't want the protocols to autoload 870 * or depend on ctnetlink */ 871int nf_ct_port_tuple_to_nlattr(struct sk_buff *skb, 872 const struct nf_conntrack_tuple *tuple) 873{ 874 NLA_PUT_BE16(skb, CTA_PROTO_SRC_PORT, tuple->src.u.tcp.port); 875 NLA_PUT_BE16(skb, CTA_PROTO_DST_PORT, tuple->dst.u.tcp.port); 876 return 0; 877 878nla_put_failure: 879 return -1; 880} 881EXPORT_SYMBOL_GPL(nf_ct_port_tuple_to_nlattr); 882 883const struct nla_policy nf_ct_port_nla_policy[CTA_PROTO_MAX+1] = { 884 [CTA_PROTO_SRC_PORT] = { .type = NLA_U16 }, 885 [CTA_PROTO_DST_PORT] = { .type = NLA_U16 }, 886}; 887EXPORT_SYMBOL_GPL(nf_ct_port_nla_policy); 888 889int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[], 890 struct nf_conntrack_tuple *t) 891{ 892 if (!tb[CTA_PROTO_SRC_PORT] || !tb[CTA_PROTO_DST_PORT]) 893 return -EINVAL; 894 895 t->src.u.tcp.port = nla_get_be16(tb[CTA_PROTO_SRC_PORT]); 896 t->dst.u.tcp.port = nla_get_be16(tb[CTA_PROTO_DST_PORT]); 897 898 return 0; 899} 900EXPORT_SYMBOL_GPL(nf_ct_port_nlattr_to_tuple); 901 902int nf_ct_port_nlattr_tuple_size(void) 903{ 904 return nla_policy_len(nf_ct_port_nla_policy, CTA_PROTO_MAX + 1); 905} 906EXPORT_SYMBOL_GPL(nf_ct_port_nlattr_tuple_size); 907#endif 908 909/* Used by ipt_REJECT and ip6t_REJECT. */ 910static void nf_conntrack_attach(struct sk_buff *nskb, struct sk_buff *skb) 911{ 912 struct nf_conn *ct; 913 enum ip_conntrack_info ctinfo; 914 915 /* This ICMP is in reverse direction to the packet which caused it */ 916 ct = nf_ct_get(skb, &ctinfo); 917 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) 918 ctinfo = IP_CT_RELATED + IP_CT_IS_REPLY; 919 else 920 ctinfo = IP_CT_RELATED; 921 922 /* Attach to new skbuff, and increment count */ 923 nskb->nfct = &ct->ct_general; 924 nskb->nfctinfo = ctinfo; 925 nf_conntrack_get(nskb->nfct); 926} 927 928/* Bring out ya dead! */ 929static struct nf_conn * 930get_next_corpse(struct net *net, int (*iter)(struct nf_conn *i, void *data), 931 void *data, unsigned int *bucket) 932{ 933 struct nf_conntrack_tuple_hash *h; 934 struct nf_conn *ct; 935 struct hlist_nulls_node *n; 936 937 spin_lock_bh(&nf_conntrack_lock); 938 for (; *bucket < nf_conntrack_htable_size; (*bucket)++) { 939 hlist_nulls_for_each_entry(h, n, &net->ct.hash[*bucket], hnnode) { 940 ct = nf_ct_tuplehash_to_ctrack(h); 941 if (iter(ct, data)) 942 goto found; 943 } 944 } 945 hlist_nulls_for_each_entry(h, n, &net->ct.unconfirmed, hnnode) { 946 ct = nf_ct_tuplehash_to_ctrack(h); 947 if (iter(ct, data)) 948 set_bit(IPS_DYING_BIT, &ct->status); 949 } 950 spin_unlock_bh(&nf_conntrack_lock); 951 return NULL; 952found: 953 atomic_inc(&ct->ct_general.use); 954 spin_unlock_bh(&nf_conntrack_lock); 955 return ct; 956} 957 958void nf_ct_iterate_cleanup(struct net *net, 959 int (*iter)(struct nf_conn *i, void *data), 960 void *data) 961{ 962 struct nf_conn *ct; 963 unsigned int bucket = 0; 964 965 while ((ct = get_next_corpse(net, iter, data, &bucket)) != NULL) { 966 /* Time to push up daises... */ 967 if (del_timer(&ct->timeout)) 968 death_by_timeout((unsigned long)ct); 969 /* ... else the timer will get him soon. */ 970 971 nf_ct_put(ct); 972 } 973} 974EXPORT_SYMBOL_GPL(nf_ct_iterate_cleanup); 975 976struct __nf_ct_flush_report { 977 u32 pid; 978 int report; 979}; 980 981static int kill_report(struct nf_conn *i, void *data) 982{ 983 struct __nf_ct_flush_report *fr = (struct __nf_ct_flush_report *)data; 984 985 /* get_next_corpse sets the dying bit for us */ 986 nf_conntrack_event_report(IPCT_DESTROY, 987 i, 988 fr->pid, 989 fr->report); 990 return 1; 991} 992 993static int kill_all(struct nf_conn *i, void *data) 994{ 995 return 1; 996} 997 998void nf_ct_free_hashtable(void *hash, int vmalloced, unsigned int size) 999{ 1000 if (vmalloced) 1001 vfree(hash); 1002 else 1003 free_pages((unsigned long)hash, 1004 get_order(sizeof(struct hlist_head) * size)); 1005} 1006EXPORT_SYMBOL_GPL(nf_ct_free_hashtable); 1007 1008void nf_conntrack_flush_report(struct net *net, u32 pid, int report) 1009{ 1010 struct __nf_ct_flush_report fr = { 1011 .pid = pid, 1012 .report = report, 1013 }; 1014 nf_ct_iterate_cleanup(net, kill_report, &fr); 1015} 1016EXPORT_SYMBOL_GPL(nf_conntrack_flush_report); 1017 1018static void nf_conntrack_cleanup_init_net(void) 1019{ 1020 nf_conntrack_helper_fini(); 1021 nf_conntrack_proto_fini(); 1022 kmem_cache_destroy(nf_conntrack_cachep); 1023} 1024 1025static void nf_conntrack_cleanup_net(struct net *net) 1026{ 1027 i_see_dead_people: 1028 nf_ct_iterate_cleanup(net, kill_all, NULL); 1029 if (atomic_read(&net->ct.count) != 0) { 1030 schedule(); 1031 goto i_see_dead_people; 1032 } 1033 /* wait until all references to nf_conntrack_untracked are dropped */ 1034 while (atomic_read(&nf_conntrack_untracked.ct_general.use) > 1) 1035 schedule(); 1036 1037 nf_ct_free_hashtable(net->ct.hash, net->ct.hash_vmalloc, 1038 nf_conntrack_htable_size); 1039 nf_conntrack_ecache_fini(net); 1040 nf_conntrack_acct_fini(net); 1041 nf_conntrack_expect_fini(net); 1042 free_percpu(net->ct.stat); 1043} 1044 1045/* Mishearing the voices in his head, our hero wonders how he's 1046 supposed to kill the mall. */ 1047void nf_conntrack_cleanup(struct net *net) 1048{ 1049 if (net_eq(net, &init_net)) 1050 rcu_assign_pointer(ip_ct_attach, NULL); 1051 1052 /* This makes sure all current packets have passed through 1053 netfilter framework. Roll on, two-stage module 1054 delete... */ 1055 synchronize_net(); 1056 1057 nf_conntrack_cleanup_net(net); 1058 1059 if (net_eq(net, &init_net)) { 1060 rcu_assign_pointer(nf_ct_destroy, NULL); 1061 nf_conntrack_cleanup_init_net(); 1062 } 1063} 1064 1065void *nf_ct_alloc_hashtable(unsigned int *sizep, int *vmalloced, int nulls) 1066{ 1067 struct hlist_nulls_head *hash; 1068 unsigned int nr_slots, i; 1069 size_t sz; 1070 1071 *vmalloced = 0; 1072 1073 BUILD_BUG_ON(sizeof(struct hlist_nulls_head) != sizeof(struct hlist_head)); 1074 nr_slots = *sizep = roundup(*sizep, PAGE_SIZE / sizeof(struct hlist_nulls_head)); 1075 sz = nr_slots * sizeof(struct hlist_nulls_head); 1076 hash = (void *)__get_free_pages(GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO, 1077 get_order(sz)); 1078 if (!hash) { 1079 *vmalloced = 1; 1080 printk(KERN_WARNING "nf_conntrack: falling back to vmalloc.\n"); 1081 hash = __vmalloc(sz, GFP_KERNEL | __GFP_ZERO, PAGE_KERNEL); 1082 } 1083 1084 if (hash && nulls) 1085 for (i = 0; i < nr_slots; i++) 1086 INIT_HLIST_NULLS_HEAD(&hash[i], i); 1087 1088 return hash; 1089} 1090EXPORT_SYMBOL_GPL(nf_ct_alloc_hashtable); 1091 1092int nf_conntrack_set_hashsize(const char *val, struct kernel_param *kp) 1093{ 1094 int i, bucket, vmalloced, old_vmalloced; 1095 unsigned int hashsize, old_size; 1096 int rnd; 1097 struct hlist_nulls_head *hash, *old_hash; 1098 struct nf_conntrack_tuple_hash *h; 1099 1100 /* On boot, we can set this without any fancy locking. */ 1101 if (!nf_conntrack_htable_size) 1102 return param_set_uint(val, kp); 1103 1104 hashsize = simple_strtoul(val, NULL, 0); 1105 if (!hashsize) 1106 return -EINVAL; 1107 1108 hash = nf_ct_alloc_hashtable(&hashsize, &vmalloced, 1); 1109 if (!hash) 1110 return -ENOMEM; 1111 1112 /* We have to rehahs for the new table anyway, so we also can 1113 * use a newrandom seed */ 1114 get_random_bytes(&rnd, sizeof(rnd)); 1115 1116 /* Lookups in the old hash might happen in parallel, which means we 1117 * might get false negatives during connection lookup. New connections 1118 * created because of a false negative won't make it into the hash 1119 * though since that required taking the lock. 1120 */ 1121 spin_lock_bh(&nf_conntrack_lock); 1122 for (i = 0; i < nf_conntrack_htable_size; i++) { 1123 while (!hlist_nulls_empty(&init_net.ct.hash[i])) { 1124 h = hlist_nulls_entry(init_net.ct.hash[i].first, 1125 struct nf_conntrack_tuple_hash, hnnode); 1126 hlist_nulls_del_rcu(&h->hnnode); 1127 bucket = __hash_conntrack(&h->tuple, hashsize, rnd); 1128 hlist_nulls_add_head_rcu(&h->hnnode, &hash[bucket]); 1129 } 1130 } 1131 old_size = nf_conntrack_htable_size; 1132 old_vmalloced = init_net.ct.hash_vmalloc; 1133 old_hash = init_net.ct.hash; 1134 1135 nf_conntrack_htable_size = hashsize; 1136 init_net.ct.hash_vmalloc = vmalloced; 1137 init_net.ct.hash = hash; 1138 nf_conntrack_hash_rnd = rnd; 1139 spin_unlock_bh(&nf_conntrack_lock); 1140 1141 nf_ct_free_hashtable(old_hash, old_vmalloced, old_size); 1142 return 0; 1143} 1144EXPORT_SYMBOL_GPL(nf_conntrack_set_hashsize); 1145 1146module_param_call(hashsize, nf_conntrack_set_hashsize, param_get_uint, 1147 &nf_conntrack_htable_size, 0600); 1148 1149static int nf_conntrack_init_init_net(void) 1150{ 1151 int max_factor = 8; 1152 int ret; 1153 1154 /* Idea from tcp.c: use 1/16384 of memory. On i386: 32MB 1155 * machine has 512 buckets. >= 1GB machines have 16384 buckets. */ 1156 if (!nf_conntrack_htable_size) { 1157 nf_conntrack_htable_size 1158 = (((num_physpages << PAGE_SHIFT) / 16384) 1159 / sizeof(struct hlist_head)); 1160 if (num_physpages > (1024 * 1024 * 1024 / PAGE_SIZE)) 1161 nf_conntrack_htable_size = 16384; 1162 if (nf_conntrack_htable_size < 32) 1163 nf_conntrack_htable_size = 32; 1164 1165 /* Use a max. factor of four by default to get the same max as 1166 * with the old struct list_heads. When a table size is given 1167 * we use the old value of 8 to avoid reducing the max. 1168 * entries. */ 1169 max_factor = 4; 1170 } 1171 nf_conntrack_max = max_factor * nf_conntrack_htable_size; 1172 1173 printk("nf_conntrack version %s (%u buckets, %d max)\n", 1174 NF_CONNTRACK_VERSION, nf_conntrack_htable_size, 1175 nf_conntrack_max); 1176 1177 nf_conntrack_cachep = kmem_cache_create("nf_conntrack", 1178 sizeof(struct nf_conn), 1179 0, SLAB_DESTROY_BY_RCU, NULL); 1180 if (!nf_conntrack_cachep) { 1181 printk(KERN_ERR "Unable to create nf_conn slab cache\n"); 1182 ret = -ENOMEM; 1183 goto err_cache; 1184 } 1185 1186 ret = nf_conntrack_proto_init(); 1187 if (ret < 0) 1188 goto err_proto; 1189 1190 ret = nf_conntrack_helper_init(); 1191 if (ret < 0) 1192 goto err_helper; 1193 1194 return 0; 1195 1196err_helper: 1197 nf_conntrack_proto_fini(); 1198err_proto: 1199 kmem_cache_destroy(nf_conntrack_cachep); 1200err_cache: 1201 return ret; 1202} 1203 1204static int nf_conntrack_init_net(struct net *net) 1205{ 1206 int ret; 1207 1208 atomic_set(&net->ct.count, 0); 1209 INIT_HLIST_NULLS_HEAD(&net->ct.unconfirmed, 0); 1210 net->ct.stat = alloc_percpu(struct ip_conntrack_stat); 1211 if (!net->ct.stat) { 1212 ret = -ENOMEM; 1213 goto err_stat; 1214 } 1215 net->ct.hash = nf_ct_alloc_hashtable(&nf_conntrack_htable_size, 1216 &net->ct.hash_vmalloc, 1); 1217 if (!net->ct.hash) { 1218 ret = -ENOMEM; 1219 printk(KERN_ERR "Unable to create nf_conntrack_hash\n"); 1220 goto err_hash; 1221 } 1222 ret = nf_conntrack_expect_init(net); 1223 if (ret < 0) 1224 goto err_expect; 1225 ret = nf_conntrack_acct_init(net); 1226 if (ret < 0) 1227 goto err_acct; 1228 ret = nf_conntrack_ecache_init(net); 1229 if (ret < 0) 1230 goto err_ecache; 1231 1232 /* Set up fake conntrack: 1233 - to never be deleted, not in any hashes */ 1234#ifdef CONFIG_NET_NS 1235 nf_conntrack_untracked.ct_net = &init_net; 1236#endif 1237 atomic_set(&nf_conntrack_untracked.ct_general.use, 1); 1238 /* - and look it like as a confirmed connection */ 1239 set_bit(IPS_CONFIRMED_BIT, &nf_conntrack_untracked.status); 1240 1241 return 0; 1242 1243err_ecache: 1244 nf_conntrack_acct_fini(net); 1245err_acct: 1246 nf_conntrack_expect_fini(net); 1247err_expect: 1248 nf_ct_free_hashtable(net->ct.hash, net->ct.hash_vmalloc, 1249 nf_conntrack_htable_size); 1250err_hash: 1251 free_percpu(net->ct.stat); 1252err_stat: 1253 return ret; 1254} 1255 1256int nf_conntrack_init(struct net *net) 1257{ 1258 int ret; 1259 1260 if (net_eq(net, &init_net)) { 1261 ret = nf_conntrack_init_init_net(); 1262 if (ret < 0) 1263 goto out_init_net; 1264 } 1265 ret = nf_conntrack_init_net(net); 1266 if (ret < 0) 1267 goto out_net; 1268 1269 if (net_eq(net, &init_net)) { 1270 /* For use by REJECT target */ 1271 rcu_assign_pointer(ip_ct_attach, nf_conntrack_attach); 1272 rcu_assign_pointer(nf_ct_destroy, destroy_conntrack); 1273 } 1274 return 0; 1275 1276out_net: 1277 if (net_eq(net, &init_net)) 1278 nf_conntrack_cleanup_init_net(); 1279out_init_net: 1280 return ret; 1281} 1282