1 /* netfilter.c: look after the filters for various protocols. 2 * Heavily influenced by the old firewall.c by David Bonn and Alan Cox. 3 * 4 * Thanks to Rob `CmdrTaco' Malda for not influencing this code in any 5 * way. 6 * 7 * This code is GPL. 8 */ 9 #include <linux/kernel.h> 10 #include <linux/netfilter.h> 11 #include <net/protocol.h> 12 #include <linux/init.h> 13 #include <linux/skbuff.h> 14 #include <linux/wait.h> 15 #include <linux/module.h> 16 #include <linux/interrupt.h> 17 #include <linux/if.h> 18 #include <linux/netdevice.h> 19 #include <linux/netfilter_ipv6.h> 20 #include <linux/inetdevice.h> 21 #include <linux/proc_fs.h> 22 #include <linux/mutex.h> 23 #include <linux/mm.h> 24 #include <linux/rcupdate.h> 25 #include <net/net_namespace.h> 26 #include <net/netfilter/nf_queue.h> 27 #include <net/sock.h> 28 29 #include "nf_internals.h" 30 31 const struct nf_ipv6_ops __rcu *nf_ipv6_ops __read_mostly; 32 EXPORT_SYMBOL_GPL(nf_ipv6_ops); 33 34 DEFINE_PER_CPU(bool, nf_skb_duplicated); 35 EXPORT_SYMBOL_GPL(nf_skb_duplicated); 36 37 #ifdef CONFIG_JUMP_LABEL 38 struct static_key nf_hooks_needed[NFPROTO_NUMPROTO][NF_MAX_HOOKS]; 39 EXPORT_SYMBOL(nf_hooks_needed); 40 #endif 41 42 static DEFINE_MUTEX(nf_hook_mutex); 43 44 /* max hooks per family/hooknum */ 45 #define MAX_HOOK_COUNT 1024 46 47 #define nf_entry_dereference(e) \ 48 rcu_dereference_protected(e, lockdep_is_held(&nf_hook_mutex)) 49 50 static struct nf_hook_entries *allocate_hook_entries_size(u16 num) 51 { 52 struct nf_hook_entries *e; 53 size_t alloc = sizeof(*e) + 54 sizeof(struct nf_hook_entry) * num + 55 sizeof(struct nf_hook_ops *) * num + 56 sizeof(struct nf_hook_entries_rcu_head); 57 58 if (num == 0) 59 return NULL; 60 61 e = kvzalloc(alloc, GFP_KERNEL_ACCOUNT); 62 if (e) 63 e->num_hook_entries = num; 64 return e; 65 } 66 67 static void __nf_hook_entries_free(struct rcu_head *h) 68 { 69 struct nf_hook_entries_rcu_head *head; 70 71 head = container_of(h, struct nf_hook_entries_rcu_head, head); 72 kvfree(head->allocation); 73 } 74 75 static void nf_hook_entries_free(struct nf_hook_entries *e) 76 { 77 struct nf_hook_entries_rcu_head *head; 78 struct nf_hook_ops **ops; 79 unsigned int num; 80 81 if (!e) 82 return; 83 84 num = e->num_hook_entries; 85 ops = nf_hook_entries_get_hook_ops(e); 86 head = (void *)&ops[num]; 87 head->allocation = e; 88 call_rcu(&head->head, __nf_hook_entries_free); 89 } 90 91 static unsigned int accept_all(void *priv, 92 struct sk_buff *skb, 93 const struct nf_hook_state *state) 94 { 95 return NF_ACCEPT; /* ACCEPT makes nf_hook_slow call next hook */ 96 } 97 98 static const struct nf_hook_ops dummy_ops = { 99 .hook = accept_all, 100 .priority = INT_MIN, 101 }; 102 103 static struct nf_hook_entries * 104 nf_hook_entries_grow(const struct nf_hook_entries *old, 105 const struct nf_hook_ops *reg) 106 { 107 unsigned int i, alloc_entries, nhooks, old_entries; 108 struct nf_hook_ops **orig_ops = NULL; 109 struct nf_hook_ops **new_ops; 110 struct nf_hook_entries *new; 111 bool inserted = false; 112 113 alloc_entries = 1; 114 old_entries = old ? old->num_hook_entries : 0; 115 116 if (old) { 117 orig_ops = nf_hook_entries_get_hook_ops(old); 118 119 for (i = 0; i < old_entries; i++) { 120 if (orig_ops[i] != &dummy_ops) 121 alloc_entries++; 122 } 123 } 124 125 if (alloc_entries > MAX_HOOK_COUNT) 126 return ERR_PTR(-E2BIG); 127 128 new = allocate_hook_entries_size(alloc_entries); 129 if (!new) 130 return ERR_PTR(-ENOMEM); 131 132 new_ops = nf_hook_entries_get_hook_ops(new); 133 134 i = 0; 135 nhooks = 0; 136 while (i < old_entries) { 137 if (orig_ops[i] == &dummy_ops) { 138 ++i; 139 continue; 140 } 141 142 if (inserted || reg->priority > orig_ops[i]->priority) { 143 new_ops[nhooks] = (void *)orig_ops[i]; 144 new->hooks[nhooks] = old->hooks[i]; 145 i++; 146 } else { 147 new_ops[nhooks] = (void *)reg; 148 new->hooks[nhooks].hook = reg->hook; 149 new->hooks[nhooks].priv = reg->priv; 150 inserted = true; 151 } 152 nhooks++; 153 } 154 155 if (!inserted) { 156 new_ops[nhooks] = (void *)reg; 157 new->hooks[nhooks].hook = reg->hook; 158 new->hooks[nhooks].priv = reg->priv; 159 } 160 161 return new; 162 } 163 164 static void hooks_validate(const struct nf_hook_entries *hooks) 165 { 166 #ifdef CONFIG_DEBUG_MISC 167 struct nf_hook_ops **orig_ops; 168 int prio = INT_MIN; 169 size_t i = 0; 170 171 orig_ops = nf_hook_entries_get_hook_ops(hooks); 172 173 for (i = 0; i < hooks->num_hook_entries; i++) { 174 if (orig_ops[i] == &dummy_ops) 175 continue; 176 177 WARN_ON(orig_ops[i]->priority < prio); 178 179 if (orig_ops[i]->priority > prio) 180 prio = orig_ops[i]->priority; 181 } 182 #endif 183 } 184 185 int nf_hook_entries_insert_raw(struct nf_hook_entries __rcu **pp, 186 const struct nf_hook_ops *reg) 187 { 188 struct nf_hook_entries *new_hooks; 189 struct nf_hook_entries *p; 190 191 p = rcu_dereference_raw(*pp); 192 new_hooks = nf_hook_entries_grow(p, reg); 193 if (IS_ERR(new_hooks)) 194 return PTR_ERR(new_hooks); 195 196 hooks_validate(new_hooks); 197 198 rcu_assign_pointer(*pp, new_hooks); 199 200 BUG_ON(p == new_hooks); 201 nf_hook_entries_free(p); 202 return 0; 203 } 204 EXPORT_SYMBOL_GPL(nf_hook_entries_insert_raw); 205 206 /* 207 * __nf_hook_entries_try_shrink - try to shrink hook array 208 * 209 * @old -- current hook blob at @pp 210 * @pp -- location of hook blob 211 * 212 * Hook unregistration must always succeed, so to-be-removed hooks 213 * are replaced by a dummy one that will just move to next hook. 214 * 215 * This counts the current dummy hooks, attempts to allocate new blob, 216 * copies the live hooks, then replaces and discards old one. 217 * 218 * return values: 219 * 220 * Returns address to free, or NULL. 221 */ 222 static void *__nf_hook_entries_try_shrink(struct nf_hook_entries *old, 223 struct nf_hook_entries __rcu **pp) 224 { 225 unsigned int i, j, skip = 0, hook_entries; 226 struct nf_hook_entries *new = NULL; 227 struct nf_hook_ops **orig_ops; 228 struct nf_hook_ops **new_ops; 229 230 if (WARN_ON_ONCE(!old)) 231 return NULL; 232 233 orig_ops = nf_hook_entries_get_hook_ops(old); 234 for (i = 0; i < old->num_hook_entries; i++) { 235 if (orig_ops[i] == &dummy_ops) 236 skip++; 237 } 238 239 /* if skip == hook_entries all hooks have been removed */ 240 hook_entries = old->num_hook_entries; 241 if (skip == hook_entries) 242 goto out_assign; 243 244 if (skip == 0) 245 return NULL; 246 247 hook_entries -= skip; 248 new = allocate_hook_entries_size(hook_entries); 249 if (!new) 250 return NULL; 251 252 new_ops = nf_hook_entries_get_hook_ops(new); 253 for (i = 0, j = 0; i < old->num_hook_entries; i++) { 254 if (orig_ops[i] == &dummy_ops) 255 continue; 256 new->hooks[j] = old->hooks[i]; 257 new_ops[j] = (void *)orig_ops[i]; 258 j++; 259 } 260 hooks_validate(new); 261 out_assign: 262 rcu_assign_pointer(*pp, new); 263 return old; 264 } 265 266 static struct nf_hook_entries __rcu ** 267 nf_hook_entry_head(struct net *net, int pf, unsigned int hooknum, 268 struct net_device *dev) 269 { 270 switch (pf) { 271 case NFPROTO_NETDEV: 272 break; 273 #ifdef CONFIG_NETFILTER_FAMILY_ARP 274 case NFPROTO_ARP: 275 if (WARN_ON_ONCE(ARRAY_SIZE(net->nf.hooks_arp) <= hooknum)) 276 return NULL; 277 return net->nf.hooks_arp + hooknum; 278 #endif 279 #ifdef CONFIG_NETFILTER_FAMILY_BRIDGE 280 case NFPROTO_BRIDGE: 281 if (WARN_ON_ONCE(ARRAY_SIZE(net->nf.hooks_bridge) <= hooknum)) 282 return NULL; 283 return net->nf.hooks_bridge + hooknum; 284 #endif 285 #ifdef CONFIG_NETFILTER_INGRESS 286 case NFPROTO_INET: 287 if (WARN_ON_ONCE(hooknum != NF_INET_INGRESS)) 288 return NULL; 289 if (!dev || dev_net(dev) != net) { 290 WARN_ON_ONCE(1); 291 return NULL; 292 } 293 return &dev->nf_hooks_ingress; 294 #endif 295 case NFPROTO_IPV4: 296 if (WARN_ON_ONCE(ARRAY_SIZE(net->nf.hooks_ipv4) <= hooknum)) 297 return NULL; 298 return net->nf.hooks_ipv4 + hooknum; 299 case NFPROTO_IPV6: 300 if (WARN_ON_ONCE(ARRAY_SIZE(net->nf.hooks_ipv6) <= hooknum)) 301 return NULL; 302 return net->nf.hooks_ipv6 + hooknum; 303 default: 304 WARN_ON_ONCE(1); 305 return NULL; 306 } 307 308 #ifdef CONFIG_NETFILTER_INGRESS 309 if (hooknum == NF_NETDEV_INGRESS) { 310 if (dev && dev_net(dev) == net) 311 return &dev->nf_hooks_ingress; 312 } 313 #endif 314 #ifdef CONFIG_NETFILTER_EGRESS 315 if (hooknum == NF_NETDEV_EGRESS) { 316 if (dev && dev_net(dev) == net) 317 return &dev->nf_hooks_egress; 318 } 319 #endif 320 WARN_ON_ONCE(1); 321 return NULL; 322 } 323 324 static int nf_ingress_check(struct net *net, const struct nf_hook_ops *reg, 325 int hooknum) 326 { 327 #ifndef CONFIG_NETFILTER_INGRESS 328 if (reg->hooknum == hooknum) 329 return -EOPNOTSUPP; 330 #endif 331 if (reg->hooknum != hooknum || 332 !reg->dev || dev_net(reg->dev) != net) 333 return -EINVAL; 334 335 return 0; 336 } 337 338 static inline bool __maybe_unused nf_ingress_hook(const struct nf_hook_ops *reg, 339 int pf) 340 { 341 if ((pf == NFPROTO_NETDEV && reg->hooknum == NF_NETDEV_INGRESS) || 342 (pf == NFPROTO_INET && reg->hooknum == NF_INET_INGRESS)) 343 return true; 344 345 return false; 346 } 347 348 static inline bool __maybe_unused nf_egress_hook(const struct nf_hook_ops *reg, 349 int pf) 350 { 351 return pf == NFPROTO_NETDEV && reg->hooknum == NF_NETDEV_EGRESS; 352 } 353 354 static void nf_static_key_inc(const struct nf_hook_ops *reg, int pf) 355 { 356 #ifdef CONFIG_JUMP_LABEL 357 int hooknum; 358 359 if (pf == NFPROTO_INET && reg->hooknum == NF_INET_INGRESS) { 360 pf = NFPROTO_NETDEV; 361 hooknum = NF_NETDEV_INGRESS; 362 } else { 363 hooknum = reg->hooknum; 364 } 365 static_key_slow_inc(&nf_hooks_needed[pf][hooknum]); 366 #endif 367 } 368 369 static void nf_static_key_dec(const struct nf_hook_ops *reg, int pf) 370 { 371 #ifdef CONFIG_JUMP_LABEL 372 int hooknum; 373 374 if (pf == NFPROTO_INET && reg->hooknum == NF_INET_INGRESS) { 375 pf = NFPROTO_NETDEV; 376 hooknum = NF_NETDEV_INGRESS; 377 } else { 378 hooknum = reg->hooknum; 379 } 380 static_key_slow_dec(&nf_hooks_needed[pf][hooknum]); 381 #endif 382 } 383 384 static int __nf_register_net_hook(struct net *net, int pf, 385 const struct nf_hook_ops *reg) 386 { 387 struct nf_hook_entries *p, *new_hooks; 388 struct nf_hook_entries __rcu **pp; 389 int err; 390 391 switch (pf) { 392 case NFPROTO_NETDEV: 393 #ifndef CONFIG_NETFILTER_INGRESS 394 if (reg->hooknum == NF_NETDEV_INGRESS) 395 return -EOPNOTSUPP; 396 #endif 397 #ifndef CONFIG_NETFILTER_EGRESS 398 if (reg->hooknum == NF_NETDEV_EGRESS) 399 return -EOPNOTSUPP; 400 #endif 401 if ((reg->hooknum != NF_NETDEV_INGRESS && 402 reg->hooknum != NF_NETDEV_EGRESS) || 403 !reg->dev || dev_net(reg->dev) != net) 404 return -EINVAL; 405 break; 406 case NFPROTO_INET: 407 if (reg->hooknum != NF_INET_INGRESS) 408 break; 409 410 err = nf_ingress_check(net, reg, NF_INET_INGRESS); 411 if (err < 0) 412 return err; 413 break; 414 } 415 416 pp = nf_hook_entry_head(net, pf, reg->hooknum, reg->dev); 417 if (!pp) 418 return -EINVAL; 419 420 mutex_lock(&nf_hook_mutex); 421 422 p = nf_entry_dereference(*pp); 423 new_hooks = nf_hook_entries_grow(p, reg); 424 425 if (!IS_ERR(new_hooks)) { 426 hooks_validate(new_hooks); 427 rcu_assign_pointer(*pp, new_hooks); 428 } 429 430 mutex_unlock(&nf_hook_mutex); 431 if (IS_ERR(new_hooks)) 432 return PTR_ERR(new_hooks); 433 434 #ifdef CONFIG_NETFILTER_INGRESS 435 if (nf_ingress_hook(reg, pf)) 436 net_inc_ingress_queue(); 437 #endif 438 #ifdef CONFIG_NETFILTER_EGRESS 439 if (nf_egress_hook(reg, pf)) 440 net_inc_egress_queue(); 441 #endif 442 nf_static_key_inc(reg, pf); 443 444 BUG_ON(p == new_hooks); 445 nf_hook_entries_free(p); 446 return 0; 447 } 448 449 /* 450 * nf_remove_net_hook - remove a hook from blob 451 * 452 * @oldp: current address of hook blob 453 * @unreg: hook to unregister 454 * 455 * This cannot fail, hook unregistration must always succeed. 456 * Therefore replace the to-be-removed hook with a dummy hook. 457 */ 458 static bool nf_remove_net_hook(struct nf_hook_entries *old, 459 const struct nf_hook_ops *unreg) 460 { 461 struct nf_hook_ops **orig_ops; 462 unsigned int i; 463 464 orig_ops = nf_hook_entries_get_hook_ops(old); 465 for (i = 0; i < old->num_hook_entries; i++) { 466 if (orig_ops[i] != unreg) 467 continue; 468 WRITE_ONCE(old->hooks[i].hook, accept_all); 469 WRITE_ONCE(orig_ops[i], (void *)&dummy_ops); 470 return true; 471 } 472 473 return false; 474 } 475 476 static void __nf_unregister_net_hook(struct net *net, int pf, 477 const struct nf_hook_ops *reg) 478 { 479 struct nf_hook_entries __rcu **pp; 480 struct nf_hook_entries *p; 481 482 pp = nf_hook_entry_head(net, pf, reg->hooknum, reg->dev); 483 if (!pp) 484 return; 485 486 mutex_lock(&nf_hook_mutex); 487 488 p = nf_entry_dereference(*pp); 489 if (WARN_ON_ONCE(!p)) { 490 mutex_unlock(&nf_hook_mutex); 491 return; 492 } 493 494 if (nf_remove_net_hook(p, reg)) { 495 #ifdef CONFIG_NETFILTER_INGRESS 496 if (nf_ingress_hook(reg, pf)) 497 net_dec_ingress_queue(); 498 #endif 499 #ifdef CONFIG_NETFILTER_EGRESS 500 if (nf_egress_hook(reg, pf)) 501 net_dec_egress_queue(); 502 #endif 503 nf_static_key_dec(reg, pf); 504 } else { 505 WARN_ONCE(1, "hook not found, pf %d num %d", pf, reg->hooknum); 506 } 507 508 p = __nf_hook_entries_try_shrink(p, pp); 509 mutex_unlock(&nf_hook_mutex); 510 if (!p) 511 return; 512 513 nf_queue_nf_hook_drop(net); 514 nf_hook_entries_free(p); 515 } 516 517 void nf_unregister_net_hook(struct net *net, const struct nf_hook_ops *reg) 518 { 519 if (reg->pf == NFPROTO_INET) { 520 if (reg->hooknum == NF_INET_INGRESS) { 521 __nf_unregister_net_hook(net, NFPROTO_INET, reg); 522 } else { 523 __nf_unregister_net_hook(net, NFPROTO_IPV4, reg); 524 __nf_unregister_net_hook(net, NFPROTO_IPV6, reg); 525 } 526 } else { 527 __nf_unregister_net_hook(net, reg->pf, reg); 528 } 529 } 530 EXPORT_SYMBOL(nf_unregister_net_hook); 531 532 void nf_hook_entries_delete_raw(struct nf_hook_entries __rcu **pp, 533 const struct nf_hook_ops *reg) 534 { 535 struct nf_hook_entries *p; 536 537 p = rcu_dereference_raw(*pp); 538 if (nf_remove_net_hook(p, reg)) { 539 p = __nf_hook_entries_try_shrink(p, pp); 540 nf_hook_entries_free(p); 541 } 542 } 543 EXPORT_SYMBOL_GPL(nf_hook_entries_delete_raw); 544 545 int nf_register_net_hook(struct net *net, const struct nf_hook_ops *reg) 546 { 547 int err; 548 549 if (reg->pf == NFPROTO_INET) { 550 if (reg->hooknum == NF_INET_INGRESS) { 551 err = __nf_register_net_hook(net, NFPROTO_INET, reg); 552 if (err < 0) 553 return err; 554 } else { 555 err = __nf_register_net_hook(net, NFPROTO_IPV4, reg); 556 if (err < 0) 557 return err; 558 559 err = __nf_register_net_hook(net, NFPROTO_IPV6, reg); 560 if (err < 0) { 561 __nf_unregister_net_hook(net, NFPROTO_IPV4, reg); 562 return err; 563 } 564 } 565 } else { 566 err = __nf_register_net_hook(net, reg->pf, reg); 567 if (err < 0) 568 return err; 569 } 570 571 return 0; 572 } 573 EXPORT_SYMBOL(nf_register_net_hook); 574 575 int nf_register_net_hooks(struct net *net, const struct nf_hook_ops *reg, 576 unsigned int n) 577 { 578 unsigned int i; 579 int err = 0; 580 581 for (i = 0; i < n; i++) { 582 err = nf_register_net_hook(net, ®[i]); 583 if (err) 584 goto err; 585 } 586 return err; 587 588 err: 589 if (i > 0) 590 nf_unregister_net_hooks(net, reg, i); 591 return err; 592 } 593 EXPORT_SYMBOL(nf_register_net_hooks); 594 595 void nf_unregister_net_hooks(struct net *net, const struct nf_hook_ops *reg, 596 unsigned int hookcount) 597 { 598 unsigned int i; 599 600 for (i = 0; i < hookcount; i++) 601 nf_unregister_net_hook(net, ®[i]); 602 } 603 EXPORT_SYMBOL(nf_unregister_net_hooks); 604 605 /* Returns 1 if okfn() needs to be executed by the caller, 606 * -EPERM for NF_DROP, 0 otherwise. Caller must hold rcu_read_lock. */ 607 int nf_hook_slow(struct sk_buff *skb, struct nf_hook_state *state, 608 const struct nf_hook_entries *e, unsigned int s) 609 { 610 unsigned int verdict; 611 int ret; 612 613 for (; s < e->num_hook_entries; s++) { 614 verdict = nf_hook_entry_hookfn(&e->hooks[s], skb, state); 615 switch (verdict & NF_VERDICT_MASK) { 616 case NF_ACCEPT: 617 break; 618 case NF_DROP: 619 kfree_skb_reason(skb, 620 SKB_DROP_REASON_NETFILTER_DROP); 621 ret = NF_DROP_GETERR(verdict); 622 if (ret == 0) 623 ret = -EPERM; 624 return ret; 625 case NF_QUEUE: 626 ret = nf_queue(skb, state, s, verdict); 627 if (ret == 1) 628 continue; 629 return ret; 630 default: 631 /* Implicit handling for NF_STOLEN, as well as any other 632 * non conventional verdicts. 633 */ 634 return 0; 635 } 636 } 637 638 return 1; 639 } 640 EXPORT_SYMBOL(nf_hook_slow); 641 642 void nf_hook_slow_list(struct list_head *head, struct nf_hook_state *state, 643 const struct nf_hook_entries *e) 644 { 645 struct sk_buff *skb, *next; 646 struct list_head sublist; 647 int ret; 648 649 INIT_LIST_HEAD(&sublist); 650 651 list_for_each_entry_safe(skb, next, head, list) { 652 skb_list_del_init(skb); 653 ret = nf_hook_slow(skb, state, e, 0); 654 if (ret == 1) 655 list_add_tail(&skb->list, &sublist); 656 } 657 /* Put passed packets back on main list */ 658 list_splice(&sublist, head); 659 } 660 EXPORT_SYMBOL(nf_hook_slow_list); 661 662 /* This needs to be compiled in any case to avoid dependencies between the 663 * nfnetlink_queue code and nf_conntrack. 664 */ 665 const struct nfnl_ct_hook __rcu *nfnl_ct_hook __read_mostly; 666 EXPORT_SYMBOL_GPL(nfnl_ct_hook); 667 668 const struct nf_ct_hook __rcu *nf_ct_hook __read_mostly; 669 EXPORT_SYMBOL_GPL(nf_ct_hook); 670 671 #if IS_ENABLED(CONFIG_NF_CONNTRACK) 672 u8 nf_ctnetlink_has_listener; 673 EXPORT_SYMBOL_GPL(nf_ctnetlink_has_listener); 674 675 const struct nf_nat_hook __rcu *nf_nat_hook __read_mostly; 676 EXPORT_SYMBOL_GPL(nf_nat_hook); 677 678 /* This does not belong here, but locally generated errors need it if connection 679 * tracking in use: without this, connection may not be in hash table, and hence 680 * manufactured ICMP or RST packets will not be associated with it. 681 */ 682 void nf_ct_attach(struct sk_buff *new, const struct sk_buff *skb) 683 { 684 const struct nf_ct_hook *ct_hook; 685 686 if (skb->_nfct) { 687 rcu_read_lock(); 688 ct_hook = rcu_dereference(nf_ct_hook); 689 if (ct_hook) 690 ct_hook->attach(new, skb); 691 rcu_read_unlock(); 692 } 693 } 694 EXPORT_SYMBOL(nf_ct_attach); 695 696 void nf_conntrack_destroy(struct nf_conntrack *nfct) 697 { 698 const struct nf_ct_hook *ct_hook; 699 700 rcu_read_lock(); 701 ct_hook = rcu_dereference(nf_ct_hook); 702 BUG_ON(ct_hook == NULL); 703 ct_hook->destroy(nfct); 704 rcu_read_unlock(); 705 } 706 EXPORT_SYMBOL(nf_conntrack_destroy); 707 708 void nf_ct_set_closing(struct nf_conntrack *nfct) 709 { 710 const struct nf_ct_hook *ct_hook; 711 712 if (!nfct) 713 return; 714 715 rcu_read_lock(); 716 ct_hook = rcu_dereference(nf_ct_hook); 717 if (ct_hook) 718 ct_hook->set_closing(nfct); 719 720 rcu_read_unlock(); 721 } 722 EXPORT_SYMBOL_GPL(nf_ct_set_closing); 723 724 bool nf_ct_get_tuple_skb(struct nf_conntrack_tuple *dst_tuple, 725 const struct sk_buff *skb) 726 { 727 const struct nf_ct_hook *ct_hook; 728 bool ret = false; 729 730 rcu_read_lock(); 731 ct_hook = rcu_dereference(nf_ct_hook); 732 if (ct_hook) 733 ret = ct_hook->get_tuple_skb(dst_tuple, skb); 734 rcu_read_unlock(); 735 return ret; 736 } 737 EXPORT_SYMBOL(nf_ct_get_tuple_skb); 738 739 /* Built-in default zone used e.g. by modules. */ 740 const struct nf_conntrack_zone nf_ct_zone_dflt = { 741 .id = NF_CT_DEFAULT_ZONE_ID, 742 .dir = NF_CT_DEFAULT_ZONE_DIR, 743 }; 744 EXPORT_SYMBOL_GPL(nf_ct_zone_dflt); 745 #endif /* CONFIG_NF_CONNTRACK */ 746 747 static void __net_init 748 __netfilter_net_init(struct nf_hook_entries __rcu **e, int max) 749 { 750 int h; 751 752 for (h = 0; h < max; h++) 753 RCU_INIT_POINTER(e[h], NULL); 754 } 755 756 static int __net_init netfilter_net_init(struct net *net) 757 { 758 __netfilter_net_init(net->nf.hooks_ipv4, ARRAY_SIZE(net->nf.hooks_ipv4)); 759 __netfilter_net_init(net->nf.hooks_ipv6, ARRAY_SIZE(net->nf.hooks_ipv6)); 760 #ifdef CONFIG_NETFILTER_FAMILY_ARP 761 __netfilter_net_init(net->nf.hooks_arp, ARRAY_SIZE(net->nf.hooks_arp)); 762 #endif 763 #ifdef CONFIG_NETFILTER_FAMILY_BRIDGE 764 __netfilter_net_init(net->nf.hooks_bridge, ARRAY_SIZE(net->nf.hooks_bridge)); 765 #endif 766 #ifdef CONFIG_PROC_FS 767 net->nf.proc_netfilter = proc_net_mkdir(net, "netfilter", 768 net->proc_net); 769 if (!net->nf.proc_netfilter) { 770 if (!net_eq(net, &init_net)) 771 pr_err("cannot create netfilter proc entry"); 772 773 return -ENOMEM; 774 } 775 #endif 776 777 return 0; 778 } 779 780 static void __net_exit netfilter_net_exit(struct net *net) 781 { 782 remove_proc_entry("netfilter", net->proc_net); 783 } 784 785 static struct pernet_operations netfilter_net_ops = { 786 .init = netfilter_net_init, 787 .exit = netfilter_net_exit, 788 }; 789 790 int __init netfilter_init(void) 791 { 792 int ret; 793 794 ret = register_pernet_subsys(&netfilter_net_ops); 795 if (ret < 0) 796 goto err; 797 798 ret = netfilter_log_init(); 799 if (ret < 0) 800 goto err_pernet; 801 802 return 0; 803 err_pernet: 804 unregister_pernet_subsys(&netfilter_net_ops); 805 err: 806 return ret; 807 } 808