1/* 2 * Generic address resolution entity 3 * 4 * Authors: 5 * Pedro Roque <roque@di.fc.ul.pt> 6 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License 10 * as published by the Free Software Foundation; either version 11 * 2 of the License, or (at your option) any later version. 12 * 13 * Fixes: 14 * Vitaly E. Lavrov releasing NULL neighbor in neigh_add. 15 * Harald Welte Add neighbour cache statistics like rtstat 16 */ 17 18#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 19 20#include <linux/slab.h> 21#include <linux/types.h> 22#include <linux/kernel.h> 23#include <linux/module.h> 24#include <linux/socket.h> 25#include <linux/netdevice.h> 26#include <linux/proc_fs.h> 27#ifdef CONFIG_SYSCTL 28#include <linux/sysctl.h> 29#endif 30#include <linux/times.h> 31#include <net/net_namespace.h> 32#include <net/neighbour.h> 33#include <net/dst.h> 34#include <net/sock.h> 35#include <net/netevent.h> 36#include <net/netlink.h> 37#include <linux/rtnetlink.h> 38#include <linux/random.h> 39#include <linux/string.h> 40#include <linux/log2.h> 41#include <linux/inetdevice.h> 42#include <net/addrconf.h> 43 44#define DEBUG 45#define NEIGH_DEBUG 1 46#define neigh_dbg(level, fmt, ...) \ 47do { \ 48 if (level <= NEIGH_DEBUG) \ 49 pr_debug(fmt, ##__VA_ARGS__); \ 50} while (0) 51 52#define PNEIGH_HASHMASK 0xF 53 54static void neigh_timer_handler(unsigned long arg); 55static void __neigh_notify(struct neighbour *n, int type, int flags); 56static void neigh_update_notify(struct neighbour *neigh); 57static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev); 58 59#ifdef CONFIG_PROC_FS 60static const struct file_operations neigh_stat_seq_fops; 61#endif 62 63/* 64 Neighbour hash table buckets are protected with rwlock tbl->lock. 65 66 - All the scans/updates to hash buckets MUST be made under this lock. 67 - NOTHING clever should be made under this lock: no callbacks 68 to protocol backends, no attempts to send something to network. 69 It will result in deadlocks, if backend/driver wants to use neighbour 70 cache. 71 - If the entry requires some non-trivial actions, increase 72 its reference count and release table lock. 73 74 Neighbour entries are protected: 75 - with reference count. 76 - with rwlock neigh->lock 77 78 Reference count prevents destruction. 79 80 neigh->lock mainly serializes ll address data and its validity state. 81 However, the same lock is used to protect another entry fields: 82 - timer 83 - resolution queue 84 85 Again, nothing clever shall be made under neigh->lock, 86 the most complicated procedure, which we allow is dev->hard_header. 87 It is supposed, that dev->hard_header is simplistic and does 88 not make callbacks to neighbour tables. 89 */ 90 91static int neigh_blackhole(struct neighbour *neigh, struct sk_buff *skb) 92{ 93 kfree_skb(skb); 94 return -ENETDOWN; 95} 96 97static void neigh_cleanup_and_release(struct neighbour *neigh) 98{ 99 if (neigh->parms->neigh_cleanup) 100 neigh->parms->neigh_cleanup(neigh); 101 102 __neigh_notify(neigh, RTM_DELNEIGH, 0); 103 neigh_release(neigh); 104} 105 106/* 107 * It is random distribution in the interval (1/2)*base...(3/2)*base. 108 * It corresponds to default IPv6 settings and is not overridable, 109 * because it is really reasonable choice. 110 */ 111 112unsigned long neigh_rand_reach_time(unsigned long base) 113{ 114 return base ? (prandom_u32() % base) + (base >> 1) : 0; 115} 116EXPORT_SYMBOL(neigh_rand_reach_time); 117 118 119static int neigh_forced_gc(struct neigh_table *tbl) 120{ 121 int shrunk = 0; 122 int i; 123 struct neigh_hash_table *nht; 124 125 NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs); 126 127 write_lock_bh(&tbl->lock); 128 nht = rcu_dereference_protected(tbl->nht, 129 lockdep_is_held(&tbl->lock)); 130 for (i = 0; i < (1 << nht->hash_shift); i++) { 131 struct neighbour *n; 132 struct neighbour __rcu **np; 133 134 np = &nht->hash_buckets[i]; 135 while ((n = rcu_dereference_protected(*np, 136 lockdep_is_held(&tbl->lock))) != NULL) { 137 /* Neighbour record may be discarded if: 138 * - nobody refers to it. 139 * - it is not permanent 140 */ 141 write_lock(&n->lock); 142 if (atomic_read(&n->refcnt) == 1 && 143 !(n->nud_state & NUD_PERMANENT)) { 144 rcu_assign_pointer(*np, 145 rcu_dereference_protected(n->next, 146 lockdep_is_held(&tbl->lock))); 147 n->dead = 1; 148 shrunk = 1; 149 write_unlock(&n->lock); 150 neigh_cleanup_and_release(n); 151 continue; 152 } 153 write_unlock(&n->lock); 154 np = &n->next; 155 } 156 } 157 158 tbl->last_flush = jiffies; 159 160 write_unlock_bh(&tbl->lock); 161 162 return shrunk; 163} 164 165static void neigh_add_timer(struct neighbour *n, unsigned long when) 166{ 167 neigh_hold(n); 168 if (unlikely(mod_timer(&n->timer, when))) { 169 printk("NEIGH: BUG, double timer add, state is %x\n", 170 n->nud_state); 171 dump_stack(); 172 } 173} 174 175static int neigh_del_timer(struct neighbour *n) 176{ 177 if ((n->nud_state & NUD_IN_TIMER) && 178 del_timer(&n->timer)) { 179 neigh_release(n); 180 return 1; 181 } 182 return 0; 183} 184 185static void pneigh_queue_purge(struct sk_buff_head *list) 186{ 187 struct sk_buff *skb; 188 189 while ((skb = skb_dequeue(list)) != NULL) { 190 dev_put(skb->dev); 191 kfree_skb(skb); 192 } 193} 194 195static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev) 196{ 197 int i; 198 struct neigh_hash_table *nht; 199 200 nht = rcu_dereference_protected(tbl->nht, 201 lockdep_is_held(&tbl->lock)); 202 203 for (i = 0; i < (1 << nht->hash_shift); i++) { 204 struct neighbour *n; 205 struct neighbour __rcu **np = &nht->hash_buckets[i]; 206 207 while ((n = rcu_dereference_protected(*np, 208 lockdep_is_held(&tbl->lock))) != NULL) { 209 if (dev && n->dev != dev) { 210 np = &n->next; 211 continue; 212 } 213 rcu_assign_pointer(*np, 214 rcu_dereference_protected(n->next, 215 lockdep_is_held(&tbl->lock))); 216 write_lock(&n->lock); 217 neigh_del_timer(n); 218 n->dead = 1; 219 220 if (atomic_read(&n->refcnt) != 1) { 221 /* The most unpleasant situation. 222 We must destroy neighbour entry, 223 but someone still uses it. 224 225 The destroy will be delayed until 226 the last user releases us, but 227 we must kill timers etc. and move 228 it to safe state. 229 */ 230 __skb_queue_purge(&n->arp_queue); 231 n->arp_queue_len_bytes = 0; 232 n->output = neigh_blackhole; 233 if (n->nud_state & NUD_VALID) 234 n->nud_state = NUD_NOARP; 235 else 236 n->nud_state = NUD_NONE; 237 neigh_dbg(2, "neigh %p is stray\n", n); 238 } 239 write_unlock(&n->lock); 240 neigh_cleanup_and_release(n); 241 } 242 } 243} 244 245void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev) 246{ 247 write_lock_bh(&tbl->lock); 248 neigh_flush_dev(tbl, dev); 249 write_unlock_bh(&tbl->lock); 250} 251EXPORT_SYMBOL(neigh_changeaddr); 252 253int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev) 254{ 255 write_lock_bh(&tbl->lock); 256 neigh_flush_dev(tbl, dev); 257 pneigh_ifdown(tbl, dev); 258 write_unlock_bh(&tbl->lock); 259 260 del_timer_sync(&tbl->proxy_timer); 261 pneigh_queue_purge(&tbl->proxy_queue); 262 return 0; 263} 264EXPORT_SYMBOL(neigh_ifdown); 265 266static struct neighbour *neigh_alloc(struct neigh_table *tbl, struct net_device *dev) 267{ 268 struct neighbour *n = NULL; 269 unsigned long now = jiffies; 270 int entries; 271 272 entries = atomic_inc_return(&tbl->entries) - 1; 273 if (entries >= tbl->gc_thresh3 || 274 (entries >= tbl->gc_thresh2 && 275 time_after(now, tbl->last_flush + 5 * HZ))) { 276 if (!neigh_forced_gc(tbl) && 277 entries >= tbl->gc_thresh3) { 278 net_info_ratelimited("%s: neighbor table overflow!\n", 279 tbl->id); 280 NEIGH_CACHE_STAT_INC(tbl, table_fulls); 281 goto out_entries; 282 } 283 } 284 285 n = kzalloc(tbl->entry_size + dev->neigh_priv_len, GFP_ATOMIC); 286 if (!n) 287 goto out_entries; 288 289 __skb_queue_head_init(&n->arp_queue); 290 rwlock_init(&n->lock); 291 seqlock_init(&n->ha_lock); 292 n->updated = n->used = now; 293 n->nud_state = NUD_NONE; 294 n->output = neigh_blackhole; 295 seqlock_init(&n->hh.hh_lock); 296 n->parms = neigh_parms_clone(&tbl->parms); 297 setup_timer(&n->timer, neigh_timer_handler, (unsigned long)n); 298 299 NEIGH_CACHE_STAT_INC(tbl, allocs); 300 n->tbl = tbl; 301 atomic_set(&n->refcnt, 1); 302 n->dead = 1; 303out: 304 return n; 305 306out_entries: 307 atomic_dec(&tbl->entries); 308 goto out; 309} 310 311static void neigh_get_hash_rnd(u32 *x) 312{ 313 get_random_bytes(x, sizeof(*x)); 314 *x |= 1; 315} 316 317static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift) 318{ 319 size_t size = (1 << shift) * sizeof(struct neighbour *); 320 struct neigh_hash_table *ret; 321 struct neighbour __rcu **buckets; 322 int i; 323 324 ret = kmalloc(sizeof(*ret), GFP_ATOMIC); 325 if (!ret) 326 return NULL; 327 if (size <= PAGE_SIZE) 328 buckets = kzalloc(size, GFP_ATOMIC); 329 else 330 buckets = (struct neighbour __rcu **) 331 __get_free_pages(GFP_ATOMIC | __GFP_ZERO, 332 get_order(size)); 333 if (!buckets) { 334 kfree(ret); 335 return NULL; 336 } 337 ret->hash_buckets = buckets; 338 ret->hash_shift = shift; 339 for (i = 0; i < NEIGH_NUM_HASH_RND; i++) 340 neigh_get_hash_rnd(&ret->hash_rnd[i]); 341 return ret; 342} 343 344static void neigh_hash_free_rcu(struct rcu_head *head) 345{ 346 struct neigh_hash_table *nht = container_of(head, 347 struct neigh_hash_table, 348 rcu); 349 size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *); 350 struct neighbour __rcu **buckets = nht->hash_buckets; 351 352 if (size <= PAGE_SIZE) 353 kfree(buckets); 354 else 355 free_pages((unsigned long)buckets, get_order(size)); 356 kfree(nht); 357} 358 359static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl, 360 unsigned long new_shift) 361{ 362 unsigned int i, hash; 363 struct neigh_hash_table *new_nht, *old_nht; 364 365 NEIGH_CACHE_STAT_INC(tbl, hash_grows); 366 367 old_nht = rcu_dereference_protected(tbl->nht, 368 lockdep_is_held(&tbl->lock)); 369 new_nht = neigh_hash_alloc(new_shift); 370 if (!new_nht) 371 return old_nht; 372 373 for (i = 0; i < (1 << old_nht->hash_shift); i++) { 374 struct neighbour *n, *next; 375 376 for (n = rcu_dereference_protected(old_nht->hash_buckets[i], 377 lockdep_is_held(&tbl->lock)); 378 n != NULL; 379 n = next) { 380 hash = tbl->hash(n->primary_key, n->dev, 381 new_nht->hash_rnd); 382 383 hash >>= (32 - new_nht->hash_shift); 384 next = rcu_dereference_protected(n->next, 385 lockdep_is_held(&tbl->lock)); 386 387 rcu_assign_pointer(n->next, 388 rcu_dereference_protected( 389 new_nht->hash_buckets[hash], 390 lockdep_is_held(&tbl->lock))); 391 rcu_assign_pointer(new_nht->hash_buckets[hash], n); 392 } 393 } 394 395 rcu_assign_pointer(tbl->nht, new_nht); 396 call_rcu(&old_nht->rcu, neigh_hash_free_rcu); 397 return new_nht; 398} 399 400struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey, 401 struct net_device *dev) 402{ 403 struct neighbour *n; 404 405 NEIGH_CACHE_STAT_INC(tbl, lookups); 406 407 rcu_read_lock_bh(); 408 n = __neigh_lookup_noref(tbl, pkey, dev); 409 if (n) { 410 if (!atomic_inc_not_zero(&n->refcnt)) 411 n = NULL; 412 NEIGH_CACHE_STAT_INC(tbl, hits); 413 } 414 415 rcu_read_unlock_bh(); 416 return n; 417} 418EXPORT_SYMBOL(neigh_lookup); 419 420struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net, 421 const void *pkey) 422{ 423 struct neighbour *n; 424 int key_len = tbl->key_len; 425 u32 hash_val; 426 struct neigh_hash_table *nht; 427 428 NEIGH_CACHE_STAT_INC(tbl, lookups); 429 430 rcu_read_lock_bh(); 431 nht = rcu_dereference_bh(tbl->nht); 432 hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) >> (32 - nht->hash_shift); 433 434 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]); 435 n != NULL; 436 n = rcu_dereference_bh(n->next)) { 437 if (!memcmp(n->primary_key, pkey, key_len) && 438 net_eq(dev_net(n->dev), net)) { 439 if (!atomic_inc_not_zero(&n->refcnt)) 440 n = NULL; 441 NEIGH_CACHE_STAT_INC(tbl, hits); 442 break; 443 } 444 } 445 446 rcu_read_unlock_bh(); 447 return n; 448} 449EXPORT_SYMBOL(neigh_lookup_nodev); 450 451struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey, 452 struct net_device *dev, bool want_ref) 453{ 454 u32 hash_val; 455 int key_len = tbl->key_len; 456 int error; 457 struct neighbour *n1, *rc, *n = neigh_alloc(tbl, dev); 458 struct neigh_hash_table *nht; 459 460 if (!n) { 461 rc = ERR_PTR(-ENOBUFS); 462 goto out; 463 } 464 465 memcpy(n->primary_key, pkey, key_len); 466 n->dev = dev; 467 dev_hold(dev); 468 469 /* Protocol specific setup. */ 470 if (tbl->constructor && (error = tbl->constructor(n)) < 0) { 471 rc = ERR_PTR(error); 472 goto out_neigh_release; 473 } 474 475 if (dev->netdev_ops->ndo_neigh_construct) { 476 error = dev->netdev_ops->ndo_neigh_construct(n); 477 if (error < 0) { 478 rc = ERR_PTR(error); 479 goto out_neigh_release; 480 } 481 } 482 483 /* Device specific setup. */ 484 if (n->parms->neigh_setup && 485 (error = n->parms->neigh_setup(n)) < 0) { 486 rc = ERR_PTR(error); 487 goto out_neigh_release; 488 } 489 490 n->confirmed = jiffies - (NEIGH_VAR(n->parms, BASE_REACHABLE_TIME) << 1); 491 492 write_lock_bh(&tbl->lock); 493 nht = rcu_dereference_protected(tbl->nht, 494 lockdep_is_held(&tbl->lock)); 495 496 if (atomic_read(&tbl->entries) > (1 << nht->hash_shift)) 497 nht = neigh_hash_grow(tbl, nht->hash_shift + 1); 498 499 hash_val = tbl->hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift); 500 501 if (n->parms->dead) { 502 rc = ERR_PTR(-EINVAL); 503 goto out_tbl_unlock; 504 } 505 506 for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val], 507 lockdep_is_held(&tbl->lock)); 508 n1 != NULL; 509 n1 = rcu_dereference_protected(n1->next, 510 lockdep_is_held(&tbl->lock))) { 511 if (dev == n1->dev && !memcmp(n1->primary_key, pkey, key_len)) { 512 if (want_ref) 513 neigh_hold(n1); 514 rc = n1; 515 goto out_tbl_unlock; 516 } 517 } 518 519 n->dead = 0; 520 if (want_ref) 521 neigh_hold(n); 522 rcu_assign_pointer(n->next, 523 rcu_dereference_protected(nht->hash_buckets[hash_val], 524 lockdep_is_held(&tbl->lock))); 525 rcu_assign_pointer(nht->hash_buckets[hash_val], n); 526 write_unlock_bh(&tbl->lock); 527 neigh_dbg(2, "neigh %p is created\n", n); 528 rc = n; 529out: 530 return rc; 531out_tbl_unlock: 532 write_unlock_bh(&tbl->lock); 533out_neigh_release: 534 neigh_release(n); 535 goto out; 536} 537EXPORT_SYMBOL(__neigh_create); 538 539static u32 pneigh_hash(const void *pkey, int key_len) 540{ 541 u32 hash_val = *(u32 *)(pkey + key_len - 4); 542 hash_val ^= (hash_val >> 16); 543 hash_val ^= hash_val >> 8; 544 hash_val ^= hash_val >> 4; 545 hash_val &= PNEIGH_HASHMASK; 546 return hash_val; 547} 548 549static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n, 550 struct net *net, 551 const void *pkey, 552 int key_len, 553 struct net_device *dev) 554{ 555 while (n) { 556 if (!memcmp(n->key, pkey, key_len) && 557 net_eq(pneigh_net(n), net) && 558 (n->dev == dev || !n->dev)) 559 return n; 560 n = n->next; 561 } 562 return NULL; 563} 564 565struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl, 566 struct net *net, const void *pkey, struct net_device *dev) 567{ 568 int key_len = tbl->key_len; 569 u32 hash_val = pneigh_hash(pkey, key_len); 570 571 return __pneigh_lookup_1(tbl->phash_buckets[hash_val], 572 net, pkey, key_len, dev); 573} 574EXPORT_SYMBOL_GPL(__pneigh_lookup); 575 576struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl, 577 struct net *net, const void *pkey, 578 struct net_device *dev, int creat) 579{ 580 struct pneigh_entry *n; 581 int key_len = tbl->key_len; 582 u32 hash_val = pneigh_hash(pkey, key_len); 583 584 read_lock_bh(&tbl->lock); 585 n = __pneigh_lookup_1(tbl->phash_buckets[hash_val], 586 net, pkey, key_len, dev); 587 read_unlock_bh(&tbl->lock); 588 589 if (n || !creat) 590 goto out; 591 592 ASSERT_RTNL(); 593 594 n = kmalloc(sizeof(*n) + key_len, GFP_KERNEL); 595 if (!n) 596 goto out; 597 598 write_pnet(&n->net, net); 599 memcpy(n->key, pkey, key_len); 600 n->dev = dev; 601 if (dev) 602 dev_hold(dev); 603 604 if (tbl->pconstructor && tbl->pconstructor(n)) { 605 if (dev) 606 dev_put(dev); 607 kfree(n); 608 n = NULL; 609 goto out; 610 } 611 612 write_lock_bh(&tbl->lock); 613 n->next = tbl->phash_buckets[hash_val]; 614 tbl->phash_buckets[hash_val] = n; 615 write_unlock_bh(&tbl->lock); 616out: 617 return n; 618} 619EXPORT_SYMBOL(pneigh_lookup); 620 621 622int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey, 623 struct net_device *dev) 624{ 625 struct pneigh_entry *n, **np; 626 int key_len = tbl->key_len; 627 u32 hash_val = pneigh_hash(pkey, key_len); 628 629 write_lock_bh(&tbl->lock); 630 for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL; 631 np = &n->next) { 632 if (!memcmp(n->key, pkey, key_len) && n->dev == dev && 633 net_eq(pneigh_net(n), net)) { 634 *np = n->next; 635 write_unlock_bh(&tbl->lock); 636 if (tbl->pdestructor) 637 tbl->pdestructor(n); 638 if (n->dev) 639 dev_put(n->dev); 640 kfree(n); 641 return 0; 642 } 643 } 644 write_unlock_bh(&tbl->lock); 645 return -ENOENT; 646} 647 648static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev) 649{ 650 struct pneigh_entry *n, **np; 651 u32 h; 652 653 for (h = 0; h <= PNEIGH_HASHMASK; h++) { 654 np = &tbl->phash_buckets[h]; 655 while ((n = *np) != NULL) { 656 if (!dev || n->dev == dev) { 657 *np = n->next; 658 if (tbl->pdestructor) 659 tbl->pdestructor(n); 660 if (n->dev) 661 dev_put(n->dev); 662 kfree(n); 663 continue; 664 } 665 np = &n->next; 666 } 667 } 668 return -ENOENT; 669} 670 671static void neigh_parms_destroy(struct neigh_parms *parms); 672 673static inline void neigh_parms_put(struct neigh_parms *parms) 674{ 675 if (atomic_dec_and_test(&parms->refcnt)) 676 neigh_parms_destroy(parms); 677} 678 679/* 680 * neighbour must already be out of the table; 681 * 682 */ 683void neigh_destroy(struct neighbour *neigh) 684{ 685 struct net_device *dev = neigh->dev; 686 687 NEIGH_CACHE_STAT_INC(neigh->tbl, destroys); 688 689 if (!neigh->dead) { 690 pr_warn("Destroying alive neighbour %p\n", neigh); 691 dump_stack(); 692 return; 693 } 694 695 if (neigh_del_timer(neigh)) 696 pr_warn("Impossible event\n"); 697 698 write_lock_bh(&neigh->lock); 699 __skb_queue_purge(&neigh->arp_queue); 700 write_unlock_bh(&neigh->lock); 701 neigh->arp_queue_len_bytes = 0; 702 703 if (dev->netdev_ops->ndo_neigh_destroy) 704 dev->netdev_ops->ndo_neigh_destroy(neigh); 705 706 dev_put(dev); 707 neigh_parms_put(neigh->parms); 708 709 neigh_dbg(2, "neigh %p is destroyed\n", neigh); 710 711 atomic_dec(&neigh->tbl->entries); 712 kfree_rcu(neigh, rcu); 713} 714EXPORT_SYMBOL(neigh_destroy); 715 716/* Neighbour state is suspicious; 717 disable fast path. 718 719 Called with write_locked neigh. 720 */ 721static void neigh_suspect(struct neighbour *neigh) 722{ 723 neigh_dbg(2, "neigh %p is suspected\n", neigh); 724 725 neigh->output = neigh->ops->output; 726} 727 728/* Neighbour state is OK; 729 enable fast path. 730 731 Called with write_locked neigh. 732 */ 733static void neigh_connect(struct neighbour *neigh) 734{ 735 neigh_dbg(2, "neigh %p is connected\n", neigh); 736 737 neigh->output = neigh->ops->connected_output; 738} 739 740static void neigh_periodic_work(struct work_struct *work) 741{ 742 struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work); 743 struct neighbour *n; 744 struct neighbour __rcu **np; 745 unsigned int i; 746 struct neigh_hash_table *nht; 747 748 NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs); 749 750 write_lock_bh(&tbl->lock); 751 nht = rcu_dereference_protected(tbl->nht, 752 lockdep_is_held(&tbl->lock)); 753 754 /* 755 * periodically recompute ReachableTime from random function 756 */ 757 758 if (time_after(jiffies, tbl->last_rand + 300 * HZ)) { 759 struct neigh_parms *p; 760 tbl->last_rand = jiffies; 761 list_for_each_entry(p, &tbl->parms_list, list) 762 p->reachable_time = 763 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME)); 764 } 765 766 if (atomic_read(&tbl->entries) < tbl->gc_thresh1) 767 goto out; 768 769 for (i = 0 ; i < (1 << nht->hash_shift); i++) { 770 np = &nht->hash_buckets[i]; 771 772 while ((n = rcu_dereference_protected(*np, 773 lockdep_is_held(&tbl->lock))) != NULL) { 774 unsigned int state; 775 776 write_lock(&n->lock); 777 778 state = n->nud_state; 779 if (state & (NUD_PERMANENT | NUD_IN_TIMER)) { 780 write_unlock(&n->lock); 781 goto next_elt; 782 } 783 784 if (time_before(n->used, n->confirmed)) 785 n->used = n->confirmed; 786 787 if (atomic_read(&n->refcnt) == 1 && 788 (state == NUD_FAILED || 789 time_after(jiffies, n->used + NEIGH_VAR(n->parms, GC_STALETIME)))) { 790 *np = n->next; 791 n->dead = 1; 792 write_unlock(&n->lock); 793 neigh_cleanup_and_release(n); 794 continue; 795 } 796 write_unlock(&n->lock); 797 798next_elt: 799 np = &n->next; 800 } 801 /* 802 * It's fine to release lock here, even if hash table 803 * grows while we are preempted. 804 */ 805 write_unlock_bh(&tbl->lock); 806 cond_resched(); 807 write_lock_bh(&tbl->lock); 808 nht = rcu_dereference_protected(tbl->nht, 809 lockdep_is_held(&tbl->lock)); 810 } 811out: 812 /* Cycle through all hash buckets every BASE_REACHABLE_TIME/2 ticks. 813 * ARP entry timeouts range from 1/2 BASE_REACHABLE_TIME to 3/2 814 * BASE_REACHABLE_TIME. 815 */ 816 queue_delayed_work(system_power_efficient_wq, &tbl->gc_work, 817 NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME) >> 1); 818 write_unlock_bh(&tbl->lock); 819} 820 821static __inline__ int neigh_max_probes(struct neighbour *n) 822{ 823 struct neigh_parms *p = n->parms; 824 return NEIGH_VAR(p, UCAST_PROBES) + NEIGH_VAR(p, APP_PROBES) + 825 (n->nud_state & NUD_PROBE ? NEIGH_VAR(p, MCAST_REPROBES) : 826 NEIGH_VAR(p, MCAST_PROBES)); 827} 828 829static void neigh_invalidate(struct neighbour *neigh) 830 __releases(neigh->lock) 831 __acquires(neigh->lock) 832{ 833 struct sk_buff *skb; 834 835 NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed); 836 neigh_dbg(2, "neigh %p is failed\n", neigh); 837 neigh->updated = jiffies; 838 839 /* It is very thin place. report_unreachable is very complicated 840 routine. Particularly, it can hit the same neighbour entry! 841 842 So that, we try to be accurate and avoid dead loop. --ANK 843 */ 844 while (neigh->nud_state == NUD_FAILED && 845 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) { 846 write_unlock(&neigh->lock); 847 neigh->ops->error_report(neigh, skb); 848 write_lock(&neigh->lock); 849 } 850 __skb_queue_purge(&neigh->arp_queue); 851 neigh->arp_queue_len_bytes = 0; 852} 853 854static void neigh_probe(struct neighbour *neigh) 855 __releases(neigh->lock) 856{ 857 struct sk_buff *skb = skb_peek_tail(&neigh->arp_queue); 858 /* keep skb alive even if arp_queue overflows */ 859 if (skb) 860 skb = skb_clone(skb, GFP_ATOMIC); 861 write_unlock(&neigh->lock); 862 neigh->ops->solicit(neigh, skb); 863 atomic_inc(&neigh->probes); 864 kfree_skb(skb); 865} 866 867/* Called when a timer expires for a neighbour entry. */ 868 869static void neigh_timer_handler(unsigned long arg) 870{ 871 unsigned long now, next; 872 struct neighbour *neigh = (struct neighbour *)arg; 873 unsigned int state; 874 int notify = 0; 875 876 write_lock(&neigh->lock); 877 878 state = neigh->nud_state; 879 now = jiffies; 880 next = now + HZ; 881 882 if (!(state & NUD_IN_TIMER)) 883 goto out; 884 885 if (state & NUD_REACHABLE) { 886 if (time_before_eq(now, 887 neigh->confirmed + neigh->parms->reachable_time)) { 888 neigh_dbg(2, "neigh %p is still alive\n", neigh); 889 next = neigh->confirmed + neigh->parms->reachable_time; 890 } else if (time_before_eq(now, 891 neigh->used + 892 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) { 893 neigh_dbg(2, "neigh %p is delayed\n", neigh); 894 neigh->nud_state = NUD_DELAY; 895 neigh->updated = jiffies; 896 neigh_suspect(neigh); 897 next = now + NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME); 898 } else { 899 neigh_dbg(2, "neigh %p is suspected\n", neigh); 900 neigh->nud_state = NUD_STALE; 901 neigh->updated = jiffies; 902 neigh_suspect(neigh); 903 notify = 1; 904 } 905 } else if (state & NUD_DELAY) { 906 if (time_before_eq(now, 907 neigh->confirmed + 908 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) { 909 neigh_dbg(2, "neigh %p is now reachable\n", neigh); 910 neigh->nud_state = NUD_REACHABLE; 911 neigh->updated = jiffies; 912 neigh_connect(neigh); 913 notify = 1; 914 next = neigh->confirmed + neigh->parms->reachable_time; 915 } else { 916 neigh_dbg(2, "neigh %p is probed\n", neigh); 917 neigh->nud_state = NUD_PROBE; 918 neigh->updated = jiffies; 919 atomic_set(&neigh->probes, 0); 920 notify = 1; 921 next = now + NEIGH_VAR(neigh->parms, RETRANS_TIME); 922 } 923 } else { 924 /* NUD_PROBE|NUD_INCOMPLETE */ 925 next = now + NEIGH_VAR(neigh->parms, RETRANS_TIME); 926 } 927 928 if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) && 929 atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) { 930 neigh->nud_state = NUD_FAILED; 931 notify = 1; 932 neigh_invalidate(neigh); 933 goto out; 934 } 935 936 if (neigh->nud_state & NUD_IN_TIMER) { 937 if (time_before(next, jiffies + HZ/2)) 938 next = jiffies + HZ/2; 939 if (!mod_timer(&neigh->timer, next)) 940 neigh_hold(neigh); 941 } 942 if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) { 943 neigh_probe(neigh); 944 } else { 945out: 946 write_unlock(&neigh->lock); 947 } 948 949 if (notify) 950 neigh_update_notify(neigh); 951 952 neigh_release(neigh); 953} 954 955int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb) 956{ 957 int rc; 958 bool immediate_probe = false; 959 960 write_lock_bh(&neigh->lock); 961 962 rc = 0; 963 if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE)) 964 goto out_unlock_bh; 965 if (neigh->dead) 966 goto out_dead; 967 968 if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) { 969 if (NEIGH_VAR(neigh->parms, MCAST_PROBES) + 970 NEIGH_VAR(neigh->parms, APP_PROBES)) { 971 unsigned long next, now = jiffies; 972 973 atomic_set(&neigh->probes, 974 NEIGH_VAR(neigh->parms, UCAST_PROBES)); 975 neigh->nud_state = NUD_INCOMPLETE; 976 neigh->updated = now; 977 next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME), 978 HZ/2); 979 neigh_add_timer(neigh, next); 980 immediate_probe = true; 981 } else { 982 neigh->nud_state = NUD_FAILED; 983 neigh->updated = jiffies; 984 write_unlock_bh(&neigh->lock); 985 986 kfree_skb(skb); 987 return 1; 988 } 989 } else if (neigh->nud_state & NUD_STALE) { 990 neigh_dbg(2, "neigh %p is delayed\n", neigh); 991 neigh->nud_state = NUD_DELAY; 992 neigh->updated = jiffies; 993 neigh_add_timer(neigh, jiffies + 994 NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME)); 995 } 996 997 if (neigh->nud_state == NUD_INCOMPLETE) { 998 if (skb) { 999 while (neigh->arp_queue_len_bytes + skb->truesize > 1000 NEIGH_VAR(neigh->parms, QUEUE_LEN_BYTES)) { 1001 struct sk_buff *buff; 1002 1003 buff = __skb_dequeue(&neigh->arp_queue); 1004 if (!buff) 1005 break; 1006 neigh->arp_queue_len_bytes -= buff->truesize; 1007 kfree_skb(buff); 1008 NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards); 1009 } 1010 skb_dst_force(skb); 1011 __skb_queue_tail(&neigh->arp_queue, skb); 1012 neigh->arp_queue_len_bytes += skb->truesize; 1013 } 1014 rc = 1; 1015 } 1016out_unlock_bh: 1017 if (immediate_probe) 1018 neigh_probe(neigh); 1019 else 1020 write_unlock(&neigh->lock); 1021 local_bh_enable(); 1022 return rc; 1023 1024out_dead: 1025 if (neigh->nud_state & NUD_STALE) 1026 goto out_unlock_bh; 1027 write_unlock_bh(&neigh->lock); 1028 kfree_skb(skb); 1029 return 1; 1030} 1031EXPORT_SYMBOL(__neigh_event_send); 1032 1033static void neigh_update_hhs(struct neighbour *neigh) 1034{ 1035 struct hh_cache *hh; 1036 void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *) 1037 = NULL; 1038 1039 if (neigh->dev->header_ops) 1040 update = neigh->dev->header_ops->cache_update; 1041 1042 if (update) { 1043 hh = &neigh->hh; 1044 if (hh->hh_len) { 1045 write_seqlock_bh(&hh->hh_lock); 1046 update(hh, neigh->dev, neigh->ha); 1047 write_sequnlock_bh(&hh->hh_lock); 1048 } 1049 } 1050} 1051 1052 1053 1054/* Generic update routine. 1055 -- lladdr is new lladdr or NULL, if it is not supplied. 1056 -- new is new state. 1057 -- flags 1058 NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr, 1059 if it is different. 1060 NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected" 1061 lladdr instead of overriding it 1062 if it is different. 1063 It also allows to retain current state 1064 if lladdr is unchanged. 1065 NEIGH_UPDATE_F_ADMIN means that the change is administrative. 1066 1067 NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing 1068 NTF_ROUTER flag. 1069 NEIGH_UPDATE_F_ISROUTER indicates if the neighbour is known as 1070 a router. 1071 1072 Caller MUST hold reference count on the entry. 1073 */ 1074 1075int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, 1076 u32 flags) 1077{ 1078 u8 old; 1079 int err; 1080 int notify = 0; 1081 struct net_device *dev; 1082 int update_isrouter = 0; 1083 1084 write_lock_bh(&neigh->lock); 1085 1086 dev = neigh->dev; 1087 old = neigh->nud_state; 1088 err = -EPERM; 1089 1090 if (!(flags & NEIGH_UPDATE_F_ADMIN) && 1091 (old & (NUD_NOARP | NUD_PERMANENT))) 1092 goto out; 1093 if (neigh->dead) 1094 goto out; 1095 1096 if (!(new & NUD_VALID)) { 1097 neigh_del_timer(neigh); 1098 if (old & NUD_CONNECTED) 1099 neigh_suspect(neigh); 1100 neigh->nud_state = new; 1101 err = 0; 1102 notify = old & NUD_VALID; 1103 if ((old & (NUD_INCOMPLETE | NUD_PROBE)) && 1104 (new & NUD_FAILED)) { 1105 neigh_invalidate(neigh); 1106 notify = 1; 1107 } 1108 goto out; 1109 } 1110 1111 /* Compare new lladdr with cached one */ 1112 if (!dev->addr_len) { 1113 /* First case: device needs no address. */ 1114 lladdr = neigh->ha; 1115 } else if (lladdr) { 1116 /* The second case: if something is already cached 1117 and a new address is proposed: 1118 - compare new & old 1119 - if they are different, check override flag 1120 */ 1121 if ((old & NUD_VALID) && 1122 !memcmp(lladdr, neigh->ha, dev->addr_len)) 1123 lladdr = neigh->ha; 1124 } else { 1125 /* No address is supplied; if we know something, 1126 use it, otherwise discard the request. 1127 */ 1128 err = -EINVAL; 1129 if (!(old & NUD_VALID)) 1130 goto out; 1131 lladdr = neigh->ha; 1132 } 1133 1134 if (new & NUD_CONNECTED) 1135 neigh->confirmed = jiffies; 1136 neigh->updated = jiffies; 1137 1138 /* If entry was valid and address is not changed, 1139 do not change entry state, if new one is STALE. 1140 */ 1141 err = 0; 1142 update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER; 1143 if (old & NUD_VALID) { 1144 if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) { 1145 update_isrouter = 0; 1146 if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) && 1147 (old & NUD_CONNECTED)) { 1148 lladdr = neigh->ha; 1149 new = NUD_STALE; 1150 } else 1151 goto out; 1152 } else { 1153 if (lladdr == neigh->ha && new == NUD_STALE && 1154 ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) || 1155 (old & NUD_CONNECTED)) 1156 ) 1157 new = old; 1158 } 1159 } 1160 1161 if (new != old) { 1162 neigh_del_timer(neigh); 1163 if (new & NUD_PROBE) 1164 atomic_set(&neigh->probes, 0); 1165 if (new & NUD_IN_TIMER) 1166 neigh_add_timer(neigh, (jiffies + 1167 ((new & NUD_REACHABLE) ? 1168 neigh->parms->reachable_time : 1169 0))); 1170 neigh->nud_state = new; 1171 notify = 1; 1172 } 1173 1174 if (lladdr != neigh->ha) { 1175 write_seqlock(&neigh->ha_lock); 1176 memcpy(&neigh->ha, lladdr, dev->addr_len); 1177 write_sequnlock(&neigh->ha_lock); 1178 neigh_update_hhs(neigh); 1179 if (!(new & NUD_CONNECTED)) 1180 neigh->confirmed = jiffies - 1181 (NEIGH_VAR(neigh->parms, BASE_REACHABLE_TIME) << 1); 1182 notify = 1; 1183 } 1184 if (new == old) 1185 goto out; 1186 if (new & NUD_CONNECTED) 1187 neigh_connect(neigh); 1188 else 1189 neigh_suspect(neigh); 1190 if (!(old & NUD_VALID)) { 1191 struct sk_buff *skb; 1192 1193 /* Again: avoid dead loop if something went wrong */ 1194 1195 while (neigh->nud_state & NUD_VALID && 1196 (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) { 1197 struct dst_entry *dst = skb_dst(skb); 1198 struct neighbour *n2, *n1 = neigh; 1199 write_unlock_bh(&neigh->lock); 1200 1201 rcu_read_lock(); 1202 1203 /* Why not just use 'neigh' as-is? The problem is that 1204 * things such as shaper, eql, and sch_teql can end up 1205 * using alternative, different, neigh objects to output 1206 * the packet in the output path. So what we need to do 1207 * here is re-lookup the top-level neigh in the path so 1208 * we can reinject the packet there. 1209 */ 1210 n2 = NULL; 1211 if (dst) { 1212 n2 = dst_neigh_lookup_skb(dst, skb); 1213 if (n2) 1214 n1 = n2; 1215 } 1216 n1->output(n1, skb); 1217 if (n2) 1218 neigh_release(n2); 1219 rcu_read_unlock(); 1220 1221 write_lock_bh(&neigh->lock); 1222 } 1223 __skb_queue_purge(&neigh->arp_queue); 1224 neigh->arp_queue_len_bytes = 0; 1225 } 1226out: 1227 if (update_isrouter) { 1228 neigh->flags = (flags & NEIGH_UPDATE_F_ISROUTER) ? 1229 (neigh->flags | NTF_ROUTER) : 1230 (neigh->flags & ~NTF_ROUTER); 1231 } 1232 write_unlock_bh(&neigh->lock); 1233 1234 if (notify) 1235 neigh_update_notify(neigh); 1236 1237 return err; 1238} 1239EXPORT_SYMBOL(neigh_update); 1240 1241/* Update the neigh to listen temporarily for probe responses, even if it is 1242 * in a NUD_FAILED state. The caller has to hold neigh->lock for writing. 1243 */ 1244void __neigh_set_probe_once(struct neighbour *neigh) 1245{ 1246 if (neigh->dead) 1247 return; 1248 neigh->updated = jiffies; 1249 if (!(neigh->nud_state & NUD_FAILED)) 1250 return; 1251 neigh->nud_state = NUD_INCOMPLETE; 1252 atomic_set(&neigh->probes, neigh_max_probes(neigh)); 1253 neigh_add_timer(neigh, 1254 jiffies + NEIGH_VAR(neigh->parms, RETRANS_TIME)); 1255} 1256EXPORT_SYMBOL(__neigh_set_probe_once); 1257 1258struct neighbour *neigh_event_ns(struct neigh_table *tbl, 1259 u8 *lladdr, void *saddr, 1260 struct net_device *dev) 1261{ 1262 struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev, 1263 lladdr || !dev->addr_len); 1264 if (neigh) 1265 neigh_update(neigh, lladdr, NUD_STALE, 1266 NEIGH_UPDATE_F_OVERRIDE); 1267 return neigh; 1268} 1269EXPORT_SYMBOL(neigh_event_ns); 1270 1271/* called with read_lock_bh(&n->lock); */ 1272static void neigh_hh_init(struct neighbour *n) 1273{ 1274 struct net_device *dev = n->dev; 1275 __be16 prot = n->tbl->protocol; 1276 struct hh_cache *hh = &n->hh; 1277 1278 write_lock_bh(&n->lock); 1279 1280 /* Only one thread can come in here and initialize the 1281 * hh_cache entry. 1282 */ 1283 if (!hh->hh_len) 1284 dev->header_ops->cache(n, hh, prot); 1285 1286 write_unlock_bh(&n->lock); 1287} 1288 1289/* Slow and careful. */ 1290 1291int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb) 1292{ 1293 int rc = 0; 1294 1295 if (!neigh_event_send(neigh, skb)) { 1296 int err; 1297 struct net_device *dev = neigh->dev; 1298 unsigned int seq; 1299 1300 if (dev->header_ops->cache && !neigh->hh.hh_len) 1301 neigh_hh_init(neigh); 1302 1303 do { 1304 __skb_pull(skb, skb_network_offset(skb)); 1305 seq = read_seqbegin(&neigh->ha_lock); 1306 err = dev_hard_header(skb, dev, ntohs(skb->protocol), 1307 neigh->ha, NULL, skb->len); 1308 } while (read_seqretry(&neigh->ha_lock, seq)); 1309 1310 if (err >= 0) 1311 rc = dev_queue_xmit(skb); 1312 else 1313 goto out_kfree_skb; 1314 } 1315out: 1316 return rc; 1317out_kfree_skb: 1318 rc = -EINVAL; 1319 kfree_skb(skb); 1320 goto out; 1321} 1322EXPORT_SYMBOL(neigh_resolve_output); 1323 1324/* As fast as possible without hh cache */ 1325 1326int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb) 1327{ 1328 struct net_device *dev = neigh->dev; 1329 unsigned int seq; 1330 int err; 1331 1332 do { 1333 __skb_pull(skb, skb_network_offset(skb)); 1334 seq = read_seqbegin(&neigh->ha_lock); 1335 err = dev_hard_header(skb, dev, ntohs(skb->protocol), 1336 neigh->ha, NULL, skb->len); 1337 } while (read_seqretry(&neigh->ha_lock, seq)); 1338 1339 if (err >= 0) 1340 err = dev_queue_xmit(skb); 1341 else { 1342 err = -EINVAL; 1343 kfree_skb(skb); 1344 } 1345 return err; 1346} 1347EXPORT_SYMBOL(neigh_connected_output); 1348 1349int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb) 1350{ 1351 return dev_queue_xmit(skb); 1352} 1353EXPORT_SYMBOL(neigh_direct_output); 1354 1355static void neigh_proxy_process(unsigned long arg) 1356{ 1357 struct neigh_table *tbl = (struct neigh_table *)arg; 1358 long sched_next = 0; 1359 unsigned long now = jiffies; 1360 struct sk_buff *skb, *n; 1361 1362 spin_lock(&tbl->proxy_queue.lock); 1363 1364 skb_queue_walk_safe(&tbl->proxy_queue, skb, n) { 1365 long tdif = NEIGH_CB(skb)->sched_next - now; 1366 1367 if (tdif <= 0) { 1368 struct net_device *dev = skb->dev; 1369 1370 __skb_unlink(skb, &tbl->proxy_queue); 1371 if (tbl->proxy_redo && netif_running(dev)) { 1372 rcu_read_lock(); 1373 tbl->proxy_redo(skb); 1374 rcu_read_unlock(); 1375 } else { 1376 kfree_skb(skb); 1377 } 1378 1379 dev_put(dev); 1380 } else if (!sched_next || tdif < sched_next) 1381 sched_next = tdif; 1382 } 1383 del_timer(&tbl->proxy_timer); 1384 if (sched_next) 1385 mod_timer(&tbl->proxy_timer, jiffies + sched_next); 1386 spin_unlock(&tbl->proxy_queue.lock); 1387} 1388 1389void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p, 1390 struct sk_buff *skb) 1391{ 1392 unsigned long now = jiffies; 1393 1394 unsigned long sched_next = now + (prandom_u32() % 1395 NEIGH_VAR(p, PROXY_DELAY)); 1396 1397 if (tbl->proxy_queue.qlen > NEIGH_VAR(p, PROXY_QLEN)) { 1398 kfree_skb(skb); 1399 return; 1400 } 1401 1402 NEIGH_CB(skb)->sched_next = sched_next; 1403 NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED; 1404 1405 spin_lock(&tbl->proxy_queue.lock); 1406 if (del_timer(&tbl->proxy_timer)) { 1407 if (time_before(tbl->proxy_timer.expires, sched_next)) 1408 sched_next = tbl->proxy_timer.expires; 1409 } 1410 skb_dst_drop(skb); 1411 dev_hold(skb->dev); 1412 __skb_queue_tail(&tbl->proxy_queue, skb); 1413 mod_timer(&tbl->proxy_timer, sched_next); 1414 spin_unlock(&tbl->proxy_queue.lock); 1415} 1416EXPORT_SYMBOL(pneigh_enqueue); 1417 1418static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl, 1419 struct net *net, int ifindex) 1420{ 1421 struct neigh_parms *p; 1422 1423 list_for_each_entry(p, &tbl->parms_list, list) { 1424 if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) || 1425 (!p->dev && !ifindex && net_eq(net, &init_net))) 1426 return p; 1427 } 1428 1429 return NULL; 1430} 1431 1432struct neigh_parms *neigh_parms_alloc(struct net_device *dev, 1433 struct neigh_table *tbl) 1434{ 1435 struct neigh_parms *p; 1436 struct net *net = dev_net(dev); 1437 const struct net_device_ops *ops = dev->netdev_ops; 1438 1439 p = kmemdup(&tbl->parms, sizeof(*p), GFP_KERNEL); 1440 if (p) { 1441 p->tbl = tbl; 1442 atomic_set(&p->refcnt, 1); 1443 p->reachable_time = 1444 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME)); 1445 dev_hold(dev); 1446 p->dev = dev; 1447 write_pnet(&p->net, net); 1448 p->sysctl_table = NULL; 1449 1450 if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) { 1451 dev_put(dev); 1452 kfree(p); 1453 return NULL; 1454 } 1455 1456 write_lock_bh(&tbl->lock); 1457 list_add(&p->list, &tbl->parms.list); 1458 write_unlock_bh(&tbl->lock); 1459 1460 neigh_parms_data_state_cleanall(p); 1461 } 1462 return p; 1463} 1464EXPORT_SYMBOL(neigh_parms_alloc); 1465 1466static void neigh_rcu_free_parms(struct rcu_head *head) 1467{ 1468 struct neigh_parms *parms = 1469 container_of(head, struct neigh_parms, rcu_head); 1470 1471 neigh_parms_put(parms); 1472} 1473 1474void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms) 1475{ 1476 if (!parms || parms == &tbl->parms) 1477 return; 1478 write_lock_bh(&tbl->lock); 1479 list_del(&parms->list); 1480 parms->dead = 1; 1481 write_unlock_bh(&tbl->lock); 1482 if (parms->dev) 1483 dev_put(parms->dev); 1484 call_rcu(&parms->rcu_head, neigh_rcu_free_parms); 1485} 1486EXPORT_SYMBOL(neigh_parms_release); 1487 1488static void neigh_parms_destroy(struct neigh_parms *parms) 1489{ 1490 kfree(parms); 1491} 1492 1493static struct lock_class_key neigh_table_proxy_queue_class; 1494 1495static struct neigh_table *neigh_tables[NEIGH_NR_TABLES] __read_mostly; 1496 1497void neigh_table_init(int index, struct neigh_table *tbl) 1498{ 1499 unsigned long now = jiffies; 1500 unsigned long phsize; 1501 1502 INIT_LIST_HEAD(&tbl->parms_list); 1503 list_add(&tbl->parms.list, &tbl->parms_list); 1504 write_pnet(&tbl->parms.net, &init_net); 1505 atomic_set(&tbl->parms.refcnt, 1); 1506 tbl->parms.reachable_time = 1507 neigh_rand_reach_time(NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME)); 1508 1509 tbl->stats = alloc_percpu(struct neigh_statistics); 1510 if (!tbl->stats) 1511 panic("cannot create neighbour cache statistics"); 1512 1513#ifdef CONFIG_PROC_FS 1514 if (!proc_create_data(tbl->id, 0, init_net.proc_net_stat, 1515 &neigh_stat_seq_fops, tbl)) 1516 panic("cannot create neighbour proc dir entry"); 1517#endif 1518 1519 RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3)); 1520 1521 phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *); 1522 tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL); 1523 1524 if (!tbl->nht || !tbl->phash_buckets) 1525 panic("cannot allocate neighbour cache hashes"); 1526 1527 if (!tbl->entry_size) 1528 tbl->entry_size = ALIGN(offsetof(struct neighbour, primary_key) + 1529 tbl->key_len, NEIGH_PRIV_ALIGN); 1530 else 1531 WARN_ON(tbl->entry_size % NEIGH_PRIV_ALIGN); 1532 1533 rwlock_init(&tbl->lock); 1534 INIT_DEFERRABLE_WORK(&tbl->gc_work, neigh_periodic_work); 1535 queue_delayed_work(system_power_efficient_wq, &tbl->gc_work, 1536 tbl->parms.reachable_time); 1537 setup_timer(&tbl->proxy_timer, neigh_proxy_process, (unsigned long)tbl); 1538 skb_queue_head_init_class(&tbl->proxy_queue, 1539 &neigh_table_proxy_queue_class); 1540 1541 tbl->last_flush = now; 1542 tbl->last_rand = now + tbl->parms.reachable_time * 20; 1543 1544 neigh_tables[index] = tbl; 1545} 1546EXPORT_SYMBOL(neigh_table_init); 1547 1548int neigh_table_clear(int index, struct neigh_table *tbl) 1549{ 1550 neigh_tables[index] = NULL; 1551 /* It is not clean... Fix it to unload IPv6 module safely */ 1552 cancel_delayed_work_sync(&tbl->gc_work); 1553 del_timer_sync(&tbl->proxy_timer); 1554 pneigh_queue_purge(&tbl->proxy_queue); 1555 neigh_ifdown(tbl, NULL); 1556 if (atomic_read(&tbl->entries)) 1557 pr_crit("neighbour leakage\n"); 1558 1559 call_rcu(&rcu_dereference_protected(tbl->nht, 1)->rcu, 1560 neigh_hash_free_rcu); 1561 tbl->nht = NULL; 1562 1563 kfree(tbl->phash_buckets); 1564 tbl->phash_buckets = NULL; 1565 1566 remove_proc_entry(tbl->id, init_net.proc_net_stat); 1567 1568 free_percpu(tbl->stats); 1569 tbl->stats = NULL; 1570 1571 return 0; 1572} 1573EXPORT_SYMBOL(neigh_table_clear); 1574 1575static struct neigh_table *neigh_find_table(int family) 1576{ 1577 struct neigh_table *tbl = NULL; 1578 1579 switch (family) { 1580 case AF_INET: 1581 tbl = neigh_tables[NEIGH_ARP_TABLE]; 1582 break; 1583 case AF_INET6: 1584 tbl = neigh_tables[NEIGH_ND_TABLE]; 1585 break; 1586 case AF_DECnet: 1587 tbl = neigh_tables[NEIGH_DN_TABLE]; 1588 break; 1589 } 1590 1591 return tbl; 1592} 1593 1594static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh) 1595{ 1596 struct net *net = sock_net(skb->sk); 1597 struct ndmsg *ndm; 1598 struct nlattr *dst_attr; 1599 struct neigh_table *tbl; 1600 struct neighbour *neigh; 1601 struct net_device *dev = NULL; 1602 int err = -EINVAL; 1603 1604 ASSERT_RTNL(); 1605 if (nlmsg_len(nlh) < sizeof(*ndm)) 1606 goto out; 1607 1608 dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST); 1609 if (dst_attr == NULL) 1610 goto out; 1611 1612 ndm = nlmsg_data(nlh); 1613 if (ndm->ndm_ifindex) { 1614 dev = __dev_get_by_index(net, ndm->ndm_ifindex); 1615 if (dev == NULL) { 1616 err = -ENODEV; 1617 goto out; 1618 } 1619 } 1620 1621 tbl = neigh_find_table(ndm->ndm_family); 1622 if (tbl == NULL) 1623 return -EAFNOSUPPORT; 1624 1625 if (nla_len(dst_attr) < tbl->key_len) 1626 goto out; 1627 1628 if (ndm->ndm_flags & NTF_PROXY) { 1629 err = pneigh_delete(tbl, net, nla_data(dst_attr), dev); 1630 goto out; 1631 } 1632 1633 if (dev == NULL) 1634 goto out; 1635 1636 neigh = neigh_lookup(tbl, nla_data(dst_attr), dev); 1637 if (neigh == NULL) { 1638 err = -ENOENT; 1639 goto out; 1640 } 1641 1642 err = neigh_update(neigh, NULL, NUD_FAILED, 1643 NEIGH_UPDATE_F_OVERRIDE | 1644 NEIGH_UPDATE_F_ADMIN); 1645 neigh_release(neigh); 1646 1647out: 1648 return err; 1649} 1650 1651static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh) 1652{ 1653 int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE; 1654 struct net *net = sock_net(skb->sk); 1655 struct ndmsg *ndm; 1656 struct nlattr *tb[NDA_MAX+1]; 1657 struct neigh_table *tbl; 1658 struct net_device *dev = NULL; 1659 struct neighbour *neigh; 1660 void *dst, *lladdr; 1661 int err; 1662 1663 ASSERT_RTNL(); 1664 err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, NULL); 1665 if (err < 0) 1666 goto out; 1667 1668 err = -EINVAL; 1669 if (tb[NDA_DST] == NULL) 1670 goto out; 1671 1672 ndm = nlmsg_data(nlh); 1673 if (ndm->ndm_ifindex) { 1674 dev = __dev_get_by_index(net, ndm->ndm_ifindex); 1675 if (dev == NULL) { 1676 err = -ENODEV; 1677 goto out; 1678 } 1679 1680 if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len) 1681 goto out; 1682 } 1683 1684 tbl = neigh_find_table(ndm->ndm_family); 1685 if (tbl == NULL) 1686 return -EAFNOSUPPORT; 1687 1688 if (nla_len(tb[NDA_DST]) < tbl->key_len) 1689 goto out; 1690 dst = nla_data(tb[NDA_DST]); 1691 lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL; 1692 1693 if (ndm->ndm_flags & NTF_PROXY) { 1694 struct pneigh_entry *pn; 1695 1696 err = -ENOBUFS; 1697 pn = pneigh_lookup(tbl, net, dst, dev, 1); 1698 if (pn) { 1699 pn->flags = ndm->ndm_flags; 1700 err = 0; 1701 } 1702 goto out; 1703 } 1704 1705 if (dev == NULL) 1706 goto out; 1707 1708 neigh = neigh_lookup(tbl, dst, dev); 1709 if (neigh == NULL) { 1710 if (!(nlh->nlmsg_flags & NLM_F_CREATE)) { 1711 err = -ENOENT; 1712 goto out; 1713 } 1714 1715 neigh = __neigh_lookup_errno(tbl, dst, dev); 1716 if (IS_ERR(neigh)) { 1717 err = PTR_ERR(neigh); 1718 goto out; 1719 } 1720 } else { 1721 if (nlh->nlmsg_flags & NLM_F_EXCL) { 1722 err = -EEXIST; 1723 neigh_release(neigh); 1724 goto out; 1725 } 1726 1727 if (!(nlh->nlmsg_flags & NLM_F_REPLACE)) 1728 flags &= ~NEIGH_UPDATE_F_OVERRIDE; 1729 } 1730 1731 if (ndm->ndm_flags & NTF_USE) { 1732 neigh_event_send(neigh, NULL); 1733 err = 0; 1734 } else 1735 err = neigh_update(neigh, lladdr, ndm->ndm_state, flags); 1736 neigh_release(neigh); 1737 1738out: 1739 return err; 1740} 1741 1742static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms) 1743{ 1744 struct nlattr *nest; 1745 1746 nest = nla_nest_start(skb, NDTA_PARMS); 1747 if (nest == NULL) 1748 return -ENOBUFS; 1749 1750 if ((parms->dev && 1751 nla_put_u32(skb, NDTPA_IFINDEX, parms->dev->ifindex)) || 1752 nla_put_u32(skb, NDTPA_REFCNT, atomic_read(&parms->refcnt)) || 1753 nla_put_u32(skb, NDTPA_QUEUE_LENBYTES, 1754 NEIGH_VAR(parms, QUEUE_LEN_BYTES)) || 1755 /* approximative value for deprecated QUEUE_LEN (in packets) */ 1756 nla_put_u32(skb, NDTPA_QUEUE_LEN, 1757 NEIGH_VAR(parms, QUEUE_LEN_BYTES) / SKB_TRUESIZE(ETH_FRAME_LEN)) || 1758 nla_put_u32(skb, NDTPA_PROXY_QLEN, NEIGH_VAR(parms, PROXY_QLEN)) || 1759 nla_put_u32(skb, NDTPA_APP_PROBES, NEIGH_VAR(parms, APP_PROBES)) || 1760 nla_put_u32(skb, NDTPA_UCAST_PROBES, 1761 NEIGH_VAR(parms, UCAST_PROBES)) || 1762 nla_put_u32(skb, NDTPA_MCAST_PROBES, 1763 NEIGH_VAR(parms, MCAST_PROBES)) || 1764 nla_put_u32(skb, NDTPA_MCAST_REPROBES, 1765 NEIGH_VAR(parms, MCAST_REPROBES)) || 1766 nla_put_msecs(skb, NDTPA_REACHABLE_TIME, parms->reachable_time) || 1767 nla_put_msecs(skb, NDTPA_BASE_REACHABLE_TIME, 1768 NEIGH_VAR(parms, BASE_REACHABLE_TIME)) || 1769 nla_put_msecs(skb, NDTPA_GC_STALETIME, 1770 NEIGH_VAR(parms, GC_STALETIME)) || 1771 nla_put_msecs(skb, NDTPA_DELAY_PROBE_TIME, 1772 NEIGH_VAR(parms, DELAY_PROBE_TIME)) || 1773 nla_put_msecs(skb, NDTPA_RETRANS_TIME, 1774 NEIGH_VAR(parms, RETRANS_TIME)) || 1775 nla_put_msecs(skb, NDTPA_ANYCAST_DELAY, 1776 NEIGH_VAR(parms, ANYCAST_DELAY)) || 1777 nla_put_msecs(skb, NDTPA_PROXY_DELAY, 1778 NEIGH_VAR(parms, PROXY_DELAY)) || 1779 nla_put_msecs(skb, NDTPA_LOCKTIME, 1780 NEIGH_VAR(parms, LOCKTIME))) 1781 goto nla_put_failure; 1782 return nla_nest_end(skb, nest); 1783 1784nla_put_failure: 1785 nla_nest_cancel(skb, nest); 1786 return -EMSGSIZE; 1787} 1788 1789static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl, 1790 u32 pid, u32 seq, int type, int flags) 1791{ 1792 struct nlmsghdr *nlh; 1793 struct ndtmsg *ndtmsg; 1794 1795 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags); 1796 if (nlh == NULL) 1797 return -EMSGSIZE; 1798 1799 ndtmsg = nlmsg_data(nlh); 1800 1801 read_lock_bh(&tbl->lock); 1802 ndtmsg->ndtm_family = tbl->family; 1803 ndtmsg->ndtm_pad1 = 0; 1804 ndtmsg->ndtm_pad2 = 0; 1805 1806 if (nla_put_string(skb, NDTA_NAME, tbl->id) || 1807 nla_put_msecs(skb, NDTA_GC_INTERVAL, tbl->gc_interval) || 1808 nla_put_u32(skb, NDTA_THRESH1, tbl->gc_thresh1) || 1809 nla_put_u32(skb, NDTA_THRESH2, tbl->gc_thresh2) || 1810 nla_put_u32(skb, NDTA_THRESH3, tbl->gc_thresh3)) 1811 goto nla_put_failure; 1812 { 1813 unsigned long now = jiffies; 1814 unsigned int flush_delta = now - tbl->last_flush; 1815 unsigned int rand_delta = now - tbl->last_rand; 1816 struct neigh_hash_table *nht; 1817 struct ndt_config ndc = { 1818 .ndtc_key_len = tbl->key_len, 1819 .ndtc_entry_size = tbl->entry_size, 1820 .ndtc_entries = atomic_read(&tbl->entries), 1821 .ndtc_last_flush = jiffies_to_msecs(flush_delta), 1822 .ndtc_last_rand = jiffies_to_msecs(rand_delta), 1823 .ndtc_proxy_qlen = tbl->proxy_queue.qlen, 1824 }; 1825 1826 rcu_read_lock_bh(); 1827 nht = rcu_dereference_bh(tbl->nht); 1828 ndc.ndtc_hash_rnd = nht->hash_rnd[0]; 1829 ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1); 1830 rcu_read_unlock_bh(); 1831 1832 if (nla_put(skb, NDTA_CONFIG, sizeof(ndc), &ndc)) 1833 goto nla_put_failure; 1834 } 1835 1836 { 1837 int cpu; 1838 struct ndt_stats ndst; 1839 1840 memset(&ndst, 0, sizeof(ndst)); 1841 1842 for_each_possible_cpu(cpu) { 1843 struct neigh_statistics *st; 1844 1845 st = per_cpu_ptr(tbl->stats, cpu); 1846 ndst.ndts_allocs += st->allocs; 1847 ndst.ndts_destroys += st->destroys; 1848 ndst.ndts_hash_grows += st->hash_grows; 1849 ndst.ndts_res_failed += st->res_failed; 1850 ndst.ndts_lookups += st->lookups; 1851 ndst.ndts_hits += st->hits; 1852 ndst.ndts_rcv_probes_mcast += st->rcv_probes_mcast; 1853 ndst.ndts_rcv_probes_ucast += st->rcv_probes_ucast; 1854 ndst.ndts_periodic_gc_runs += st->periodic_gc_runs; 1855 ndst.ndts_forced_gc_runs += st->forced_gc_runs; 1856 ndst.ndts_table_fulls += st->table_fulls; 1857 } 1858 1859 if (nla_put(skb, NDTA_STATS, sizeof(ndst), &ndst)) 1860 goto nla_put_failure; 1861 } 1862 1863 BUG_ON(tbl->parms.dev); 1864 if (neightbl_fill_parms(skb, &tbl->parms) < 0) 1865 goto nla_put_failure; 1866 1867 read_unlock_bh(&tbl->lock); 1868 nlmsg_end(skb, nlh); 1869 return 0; 1870 1871nla_put_failure: 1872 read_unlock_bh(&tbl->lock); 1873 nlmsg_cancel(skb, nlh); 1874 return -EMSGSIZE; 1875} 1876 1877static int neightbl_fill_param_info(struct sk_buff *skb, 1878 struct neigh_table *tbl, 1879 struct neigh_parms *parms, 1880 u32 pid, u32 seq, int type, 1881 unsigned int flags) 1882{ 1883 struct ndtmsg *ndtmsg; 1884 struct nlmsghdr *nlh; 1885 1886 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags); 1887 if (nlh == NULL) 1888 return -EMSGSIZE; 1889 1890 ndtmsg = nlmsg_data(nlh); 1891 1892 read_lock_bh(&tbl->lock); 1893 ndtmsg->ndtm_family = tbl->family; 1894 ndtmsg->ndtm_pad1 = 0; 1895 ndtmsg->ndtm_pad2 = 0; 1896 1897 if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 || 1898 neightbl_fill_parms(skb, parms) < 0) 1899 goto errout; 1900 1901 read_unlock_bh(&tbl->lock); 1902 nlmsg_end(skb, nlh); 1903 return 0; 1904errout: 1905 read_unlock_bh(&tbl->lock); 1906 nlmsg_cancel(skb, nlh); 1907 return -EMSGSIZE; 1908} 1909 1910static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = { 1911 [NDTA_NAME] = { .type = NLA_STRING }, 1912 [NDTA_THRESH1] = { .type = NLA_U32 }, 1913 [NDTA_THRESH2] = { .type = NLA_U32 }, 1914 [NDTA_THRESH3] = { .type = NLA_U32 }, 1915 [NDTA_GC_INTERVAL] = { .type = NLA_U64 }, 1916 [NDTA_PARMS] = { .type = NLA_NESTED }, 1917}; 1918 1919static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = { 1920 [NDTPA_IFINDEX] = { .type = NLA_U32 }, 1921 [NDTPA_QUEUE_LEN] = { .type = NLA_U32 }, 1922 [NDTPA_PROXY_QLEN] = { .type = NLA_U32 }, 1923 [NDTPA_APP_PROBES] = { .type = NLA_U32 }, 1924 [NDTPA_UCAST_PROBES] = { .type = NLA_U32 }, 1925 [NDTPA_MCAST_PROBES] = { .type = NLA_U32 }, 1926 [NDTPA_MCAST_REPROBES] = { .type = NLA_U32 }, 1927 [NDTPA_BASE_REACHABLE_TIME] = { .type = NLA_U64 }, 1928 [NDTPA_GC_STALETIME] = { .type = NLA_U64 }, 1929 [NDTPA_DELAY_PROBE_TIME] = { .type = NLA_U64 }, 1930 [NDTPA_RETRANS_TIME] = { .type = NLA_U64 }, 1931 [NDTPA_ANYCAST_DELAY] = { .type = NLA_U64 }, 1932 [NDTPA_PROXY_DELAY] = { .type = NLA_U64 }, 1933 [NDTPA_LOCKTIME] = { .type = NLA_U64 }, 1934}; 1935 1936static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh) 1937{ 1938 struct net *net = sock_net(skb->sk); 1939 struct neigh_table *tbl; 1940 struct ndtmsg *ndtmsg; 1941 struct nlattr *tb[NDTA_MAX+1]; 1942 bool found = false; 1943 int err, tidx; 1944 1945 err = nlmsg_parse(nlh, sizeof(*ndtmsg), tb, NDTA_MAX, 1946 nl_neightbl_policy); 1947 if (err < 0) 1948 goto errout; 1949 1950 if (tb[NDTA_NAME] == NULL) { 1951 err = -EINVAL; 1952 goto errout; 1953 } 1954 1955 ndtmsg = nlmsg_data(nlh); 1956 1957 for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) { 1958 tbl = neigh_tables[tidx]; 1959 if (!tbl) 1960 continue; 1961 if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family) 1962 continue; 1963 if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0) { 1964 found = true; 1965 break; 1966 } 1967 } 1968 1969 if (!found) 1970 return -ENOENT; 1971 1972 /* 1973 * We acquire tbl->lock to be nice to the periodic timers and 1974 * make sure they always see a consistent set of values. 1975 */ 1976 write_lock_bh(&tbl->lock); 1977 1978 if (tb[NDTA_PARMS]) { 1979 struct nlattr *tbp[NDTPA_MAX+1]; 1980 struct neigh_parms *p; 1981 int i, ifindex = 0; 1982 1983 err = nla_parse_nested(tbp, NDTPA_MAX, tb[NDTA_PARMS], 1984 nl_ntbl_parm_policy); 1985 if (err < 0) 1986 goto errout_tbl_lock; 1987 1988 if (tbp[NDTPA_IFINDEX]) 1989 ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]); 1990 1991 p = lookup_neigh_parms(tbl, net, ifindex); 1992 if (p == NULL) { 1993 err = -ENOENT; 1994 goto errout_tbl_lock; 1995 } 1996 1997 for (i = 1; i <= NDTPA_MAX; i++) { 1998 if (tbp[i] == NULL) 1999 continue; 2000 2001 switch (i) { 2002 case NDTPA_QUEUE_LEN: 2003 NEIGH_VAR_SET(p, QUEUE_LEN_BYTES, 2004 nla_get_u32(tbp[i]) * 2005 SKB_TRUESIZE(ETH_FRAME_LEN)); 2006 break; 2007 case NDTPA_QUEUE_LENBYTES: 2008 NEIGH_VAR_SET(p, QUEUE_LEN_BYTES, 2009 nla_get_u32(tbp[i])); 2010 break; 2011 case NDTPA_PROXY_QLEN: 2012 NEIGH_VAR_SET(p, PROXY_QLEN, 2013 nla_get_u32(tbp[i])); 2014 break; 2015 case NDTPA_APP_PROBES: 2016 NEIGH_VAR_SET(p, APP_PROBES, 2017 nla_get_u32(tbp[i])); 2018 break; 2019 case NDTPA_UCAST_PROBES: 2020 NEIGH_VAR_SET(p, UCAST_PROBES, 2021 nla_get_u32(tbp[i])); 2022 break; 2023 case NDTPA_MCAST_PROBES: 2024 NEIGH_VAR_SET(p, MCAST_PROBES, 2025 nla_get_u32(tbp[i])); 2026 break; 2027 case NDTPA_MCAST_REPROBES: 2028 NEIGH_VAR_SET(p, MCAST_REPROBES, 2029 nla_get_u32(tbp[i])); 2030 break; 2031 case NDTPA_BASE_REACHABLE_TIME: 2032 NEIGH_VAR_SET(p, BASE_REACHABLE_TIME, 2033 nla_get_msecs(tbp[i])); 2034 /* update reachable_time as well, otherwise, the change will 2035 * only be effective after the next time neigh_periodic_work 2036 * decides to recompute it (can be multiple minutes) 2037 */ 2038 p->reachable_time = 2039 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME)); 2040 break; 2041 case NDTPA_GC_STALETIME: 2042 NEIGH_VAR_SET(p, GC_STALETIME, 2043 nla_get_msecs(tbp[i])); 2044 break; 2045 case NDTPA_DELAY_PROBE_TIME: 2046 NEIGH_VAR_SET(p, DELAY_PROBE_TIME, 2047 nla_get_msecs(tbp[i])); 2048 break; 2049 case NDTPA_RETRANS_TIME: 2050 NEIGH_VAR_SET(p, RETRANS_TIME, 2051 nla_get_msecs(tbp[i])); 2052 break; 2053 case NDTPA_ANYCAST_DELAY: 2054 NEIGH_VAR_SET(p, ANYCAST_DELAY, 2055 nla_get_msecs(tbp[i])); 2056 break; 2057 case NDTPA_PROXY_DELAY: 2058 NEIGH_VAR_SET(p, PROXY_DELAY, 2059 nla_get_msecs(tbp[i])); 2060 break; 2061 case NDTPA_LOCKTIME: 2062 NEIGH_VAR_SET(p, LOCKTIME, 2063 nla_get_msecs(tbp[i])); 2064 break; 2065 } 2066 } 2067 } 2068 2069 err = -ENOENT; 2070 if ((tb[NDTA_THRESH1] || tb[NDTA_THRESH2] || 2071 tb[NDTA_THRESH3] || tb[NDTA_GC_INTERVAL]) && 2072 !net_eq(net, &init_net)) 2073 goto errout_tbl_lock; 2074 2075 if (tb[NDTA_THRESH1]) 2076 tbl->gc_thresh1 = nla_get_u32(tb[NDTA_THRESH1]); 2077 2078 if (tb[NDTA_THRESH2]) 2079 tbl->gc_thresh2 = nla_get_u32(tb[NDTA_THRESH2]); 2080 2081 if (tb[NDTA_THRESH3]) 2082 tbl->gc_thresh3 = nla_get_u32(tb[NDTA_THRESH3]); 2083 2084 if (tb[NDTA_GC_INTERVAL]) 2085 tbl->gc_interval = nla_get_msecs(tb[NDTA_GC_INTERVAL]); 2086 2087 err = 0; 2088 2089errout_tbl_lock: 2090 write_unlock_bh(&tbl->lock); 2091errout: 2092 return err; 2093} 2094 2095static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb) 2096{ 2097 struct net *net = sock_net(skb->sk); 2098 int family, tidx, nidx = 0; 2099 int tbl_skip = cb->args[0]; 2100 int neigh_skip = cb->args[1]; 2101 struct neigh_table *tbl; 2102 2103 family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family; 2104 2105 for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) { 2106 struct neigh_parms *p; 2107 2108 tbl = neigh_tables[tidx]; 2109 if (!tbl) 2110 continue; 2111 2112 if (tidx < tbl_skip || (family && tbl->family != family)) 2113 continue; 2114 2115 if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).portid, 2116 cb->nlh->nlmsg_seq, RTM_NEWNEIGHTBL, 2117 NLM_F_MULTI) < 0) 2118 break; 2119 2120 nidx = 0; 2121 p = list_next_entry(&tbl->parms, list); 2122 list_for_each_entry_from(p, &tbl->parms_list, list) { 2123 if (!net_eq(neigh_parms_net(p), net)) 2124 continue; 2125 2126 if (nidx < neigh_skip) 2127 goto next; 2128 2129 if (neightbl_fill_param_info(skb, tbl, p, 2130 NETLINK_CB(cb->skb).portid, 2131 cb->nlh->nlmsg_seq, 2132 RTM_NEWNEIGHTBL, 2133 NLM_F_MULTI) < 0) 2134 goto out; 2135 next: 2136 nidx++; 2137 } 2138 2139 neigh_skip = 0; 2140 } 2141out: 2142 cb->args[0] = tidx; 2143 cb->args[1] = nidx; 2144 2145 return skb->len; 2146} 2147 2148static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh, 2149 u32 pid, u32 seq, int type, unsigned int flags) 2150{ 2151 unsigned long now = jiffies; 2152 struct nda_cacheinfo ci; 2153 struct nlmsghdr *nlh; 2154 struct ndmsg *ndm; 2155 2156 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags); 2157 if (nlh == NULL) 2158 return -EMSGSIZE; 2159 2160 ndm = nlmsg_data(nlh); 2161 ndm->ndm_family = neigh->ops->family; 2162 ndm->ndm_pad1 = 0; 2163 ndm->ndm_pad2 = 0; 2164 ndm->ndm_flags = neigh->flags; 2165 ndm->ndm_type = neigh->type; 2166 ndm->ndm_ifindex = neigh->dev->ifindex; 2167 2168 if (nla_put(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key)) 2169 goto nla_put_failure; 2170 2171 read_lock_bh(&neigh->lock); 2172 ndm->ndm_state = neigh->nud_state; 2173 if (neigh->nud_state & NUD_VALID) { 2174 char haddr[MAX_ADDR_LEN]; 2175 2176 neigh_ha_snapshot(haddr, neigh, neigh->dev); 2177 if (nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, haddr) < 0) { 2178 read_unlock_bh(&neigh->lock); 2179 goto nla_put_failure; 2180 } 2181 } 2182 2183 ci.ndm_used = jiffies_to_clock_t(now - neigh->used); 2184 ci.ndm_confirmed = jiffies_to_clock_t(now - neigh->confirmed); 2185 ci.ndm_updated = jiffies_to_clock_t(now - neigh->updated); 2186 ci.ndm_refcnt = atomic_read(&neigh->refcnt) - 1; 2187 read_unlock_bh(&neigh->lock); 2188 2189 if (nla_put_u32(skb, NDA_PROBES, atomic_read(&neigh->probes)) || 2190 nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci)) 2191 goto nla_put_failure; 2192 2193 nlmsg_end(skb, nlh); 2194 return 0; 2195 2196nla_put_failure: 2197 nlmsg_cancel(skb, nlh); 2198 return -EMSGSIZE; 2199} 2200 2201static int pneigh_fill_info(struct sk_buff *skb, struct pneigh_entry *pn, 2202 u32 pid, u32 seq, int type, unsigned int flags, 2203 struct neigh_table *tbl) 2204{ 2205 struct nlmsghdr *nlh; 2206 struct ndmsg *ndm; 2207 2208 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags); 2209 if (nlh == NULL) 2210 return -EMSGSIZE; 2211 2212 ndm = nlmsg_data(nlh); 2213 ndm->ndm_family = tbl->family; 2214 ndm->ndm_pad1 = 0; 2215 ndm->ndm_pad2 = 0; 2216 ndm->ndm_flags = pn->flags | NTF_PROXY; 2217 ndm->ndm_type = RTN_UNICAST; 2218 ndm->ndm_ifindex = pn->dev ? pn->dev->ifindex : 0; 2219 ndm->ndm_state = NUD_NONE; 2220 2221 if (nla_put(skb, NDA_DST, tbl->key_len, pn->key)) 2222 goto nla_put_failure; 2223 2224 nlmsg_end(skb, nlh); 2225 return 0; 2226 2227nla_put_failure: 2228 nlmsg_cancel(skb, nlh); 2229 return -EMSGSIZE; 2230} 2231 2232static void neigh_update_notify(struct neighbour *neigh) 2233{ 2234 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh); 2235 __neigh_notify(neigh, RTM_NEWNEIGH, 0); 2236} 2237 2238static bool neigh_master_filtered(struct net_device *dev, int master_idx) 2239{ 2240 struct net_device *master; 2241 2242 if (!master_idx) 2243 return false; 2244 2245 master = netdev_master_upper_dev_get(dev); 2246 if (!master || master->ifindex != master_idx) 2247 return true; 2248 2249 return false; 2250} 2251 2252static bool neigh_ifindex_filtered(struct net_device *dev, int filter_idx) 2253{ 2254 if (filter_idx && dev->ifindex != filter_idx) 2255 return true; 2256 2257 return false; 2258} 2259 2260static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb, 2261 struct netlink_callback *cb) 2262{ 2263 struct net *net = sock_net(skb->sk); 2264 const struct nlmsghdr *nlh = cb->nlh; 2265 struct nlattr *tb[NDA_MAX + 1]; 2266 struct neighbour *n; 2267 int rc, h, s_h = cb->args[1]; 2268 int idx, s_idx = idx = cb->args[2]; 2269 struct neigh_hash_table *nht; 2270 int filter_master_idx = 0, filter_idx = 0; 2271 unsigned int flags = NLM_F_MULTI; 2272 int err; 2273 2274 err = nlmsg_parse(nlh, sizeof(struct ndmsg), tb, NDA_MAX, NULL); 2275 if (!err) { 2276 if (tb[NDA_IFINDEX]) 2277 filter_idx = nla_get_u32(tb[NDA_IFINDEX]); 2278 2279 if (tb[NDA_MASTER]) 2280 filter_master_idx = nla_get_u32(tb[NDA_MASTER]); 2281 2282 if (filter_idx || filter_master_idx) 2283 flags |= NLM_F_DUMP_FILTERED; 2284 } 2285 2286 rcu_read_lock_bh(); 2287 nht = rcu_dereference_bh(tbl->nht); 2288 2289 for (h = s_h; h < (1 << nht->hash_shift); h++) { 2290 if (h > s_h) 2291 s_idx = 0; 2292 for (n = rcu_dereference_bh(nht->hash_buckets[h]), idx = 0; 2293 n != NULL; 2294 n = rcu_dereference_bh(n->next)) { 2295 if (!net_eq(dev_net(n->dev), net)) 2296 continue; 2297 if (neigh_ifindex_filtered(n->dev, filter_idx)) 2298 continue; 2299 if (neigh_master_filtered(n->dev, filter_master_idx)) 2300 continue; 2301 if (idx < s_idx) 2302 goto next; 2303 if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid, 2304 cb->nlh->nlmsg_seq, 2305 RTM_NEWNEIGH, 2306 flags) < 0) { 2307 rc = -1; 2308 goto out; 2309 } 2310next: 2311 idx++; 2312 } 2313 } 2314 rc = skb->len; 2315out: 2316 rcu_read_unlock_bh(); 2317 cb->args[1] = h; 2318 cb->args[2] = idx; 2319 return rc; 2320} 2321 2322static int pneigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb, 2323 struct netlink_callback *cb) 2324{ 2325 struct pneigh_entry *n; 2326 struct net *net = sock_net(skb->sk); 2327 int rc, h, s_h = cb->args[3]; 2328 int idx, s_idx = idx = cb->args[4]; 2329 2330 read_lock_bh(&tbl->lock); 2331 2332 for (h = s_h; h <= PNEIGH_HASHMASK; h++) { 2333 if (h > s_h) 2334 s_idx = 0; 2335 for (n = tbl->phash_buckets[h], idx = 0; n; n = n->next) { 2336 if (pneigh_net(n) != net) 2337 continue; 2338 if (idx < s_idx) 2339 goto next; 2340 if (pneigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid, 2341 cb->nlh->nlmsg_seq, 2342 RTM_NEWNEIGH, 2343 NLM_F_MULTI, tbl) < 0) { 2344 read_unlock_bh(&tbl->lock); 2345 rc = -1; 2346 goto out; 2347 } 2348 next: 2349 idx++; 2350 } 2351 } 2352 2353 read_unlock_bh(&tbl->lock); 2354 rc = skb->len; 2355out: 2356 cb->args[3] = h; 2357 cb->args[4] = idx; 2358 return rc; 2359 2360} 2361 2362static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb) 2363{ 2364 struct neigh_table *tbl; 2365 int t, family, s_t; 2366 int proxy = 0; 2367 int err; 2368 2369 family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family; 2370 2371 /* check for full ndmsg structure presence, family member is 2372 * the same for both structures 2373 */ 2374 if (nlmsg_len(cb->nlh) >= sizeof(struct ndmsg) && 2375 ((struct ndmsg *) nlmsg_data(cb->nlh))->ndm_flags == NTF_PROXY) 2376 proxy = 1; 2377 2378 s_t = cb->args[0]; 2379 2380 for (t = 0; t < NEIGH_NR_TABLES; t++) { 2381 tbl = neigh_tables[t]; 2382 2383 if (!tbl) 2384 continue; 2385 if (t < s_t || (family && tbl->family != family)) 2386 continue; 2387 if (t > s_t) 2388 memset(&cb->args[1], 0, sizeof(cb->args) - 2389 sizeof(cb->args[0])); 2390 if (proxy) 2391 err = pneigh_dump_table(tbl, skb, cb); 2392 else 2393 err = neigh_dump_table(tbl, skb, cb); 2394 if (err < 0) 2395 break; 2396 } 2397 2398 cb->args[0] = t; 2399 return skb->len; 2400} 2401 2402void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie) 2403{ 2404 int chain; 2405 struct neigh_hash_table *nht; 2406 2407 rcu_read_lock_bh(); 2408 nht = rcu_dereference_bh(tbl->nht); 2409 2410 read_lock(&tbl->lock); /* avoid resizes */ 2411 for (chain = 0; chain < (1 << nht->hash_shift); chain++) { 2412 struct neighbour *n; 2413 2414 for (n = rcu_dereference_bh(nht->hash_buckets[chain]); 2415 n != NULL; 2416 n = rcu_dereference_bh(n->next)) 2417 cb(n, cookie); 2418 } 2419 read_unlock(&tbl->lock); 2420 rcu_read_unlock_bh(); 2421} 2422EXPORT_SYMBOL(neigh_for_each); 2423 2424/* The tbl->lock must be held as a writer and BH disabled. */ 2425void __neigh_for_each_release(struct neigh_table *tbl, 2426 int (*cb)(struct neighbour *)) 2427{ 2428 int chain; 2429 struct neigh_hash_table *nht; 2430 2431 nht = rcu_dereference_protected(tbl->nht, 2432 lockdep_is_held(&tbl->lock)); 2433 for (chain = 0; chain < (1 << nht->hash_shift); chain++) { 2434 struct neighbour *n; 2435 struct neighbour __rcu **np; 2436 2437 np = &nht->hash_buckets[chain]; 2438 while ((n = rcu_dereference_protected(*np, 2439 lockdep_is_held(&tbl->lock))) != NULL) { 2440 int release; 2441 2442 write_lock(&n->lock); 2443 release = cb(n); 2444 if (release) { 2445 rcu_assign_pointer(*np, 2446 rcu_dereference_protected(n->next, 2447 lockdep_is_held(&tbl->lock))); 2448 n->dead = 1; 2449 } else 2450 np = &n->next; 2451 write_unlock(&n->lock); 2452 if (release) 2453 neigh_cleanup_and_release(n); 2454 } 2455 } 2456} 2457EXPORT_SYMBOL(__neigh_for_each_release); 2458 2459int neigh_xmit(int index, struct net_device *dev, 2460 const void *addr, struct sk_buff *skb) 2461{ 2462 int err = -EAFNOSUPPORT; 2463 if (likely(index < NEIGH_NR_TABLES)) { 2464 struct neigh_table *tbl; 2465 struct neighbour *neigh; 2466 2467 tbl = neigh_tables[index]; 2468 if (!tbl) 2469 goto out; 2470 neigh = __neigh_lookup_noref(tbl, addr, dev); 2471 if (!neigh) 2472 neigh = __neigh_create(tbl, addr, dev, false); 2473 err = PTR_ERR(neigh); 2474 if (IS_ERR(neigh)) 2475 goto out_kfree_skb; 2476 err = neigh->output(neigh, skb); 2477 } 2478 else if (index == NEIGH_LINK_TABLE) { 2479 err = dev_hard_header(skb, dev, ntohs(skb->protocol), 2480 addr, NULL, skb->len); 2481 if (err < 0) 2482 goto out_kfree_skb; 2483 err = dev_queue_xmit(skb); 2484 } 2485out: 2486 return err; 2487out_kfree_skb: 2488 kfree_skb(skb); 2489 goto out; 2490} 2491EXPORT_SYMBOL(neigh_xmit); 2492 2493#ifdef CONFIG_PROC_FS 2494 2495static struct neighbour *neigh_get_first(struct seq_file *seq) 2496{ 2497 struct neigh_seq_state *state = seq->private; 2498 struct net *net = seq_file_net(seq); 2499 struct neigh_hash_table *nht = state->nht; 2500 struct neighbour *n = NULL; 2501 int bucket = state->bucket; 2502 2503 state->flags &= ~NEIGH_SEQ_IS_PNEIGH; 2504 for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) { 2505 n = rcu_dereference_bh(nht->hash_buckets[bucket]); 2506 2507 while (n) { 2508 if (!net_eq(dev_net(n->dev), net)) 2509 goto next; 2510 if (state->neigh_sub_iter) { 2511 loff_t fakep = 0; 2512 void *v; 2513 2514 v = state->neigh_sub_iter(state, n, &fakep); 2515 if (!v) 2516 goto next; 2517 } 2518 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP)) 2519 break; 2520 if (n->nud_state & ~NUD_NOARP) 2521 break; 2522next: 2523 n = rcu_dereference_bh(n->next); 2524 } 2525 2526 if (n) 2527 break; 2528 } 2529 state->bucket = bucket; 2530 2531 return n; 2532} 2533 2534static struct neighbour *neigh_get_next(struct seq_file *seq, 2535 struct neighbour *n, 2536 loff_t *pos) 2537{ 2538 struct neigh_seq_state *state = seq->private; 2539 struct net *net = seq_file_net(seq); 2540 struct neigh_hash_table *nht = state->nht; 2541 2542 if (state->neigh_sub_iter) { 2543 void *v = state->neigh_sub_iter(state, n, pos); 2544 if (v) 2545 return n; 2546 } 2547 n = rcu_dereference_bh(n->next); 2548 2549 while (1) { 2550 while (n) { 2551 if (!net_eq(dev_net(n->dev), net)) 2552 goto next; 2553 if (state->neigh_sub_iter) { 2554 void *v = state->neigh_sub_iter(state, n, pos); 2555 if (v) 2556 return n; 2557 goto next; 2558 } 2559 if (!(state->flags & NEIGH_SEQ_SKIP_NOARP)) 2560 break; 2561 2562 if (n->nud_state & ~NUD_NOARP) 2563 break; 2564next: 2565 n = rcu_dereference_bh(n->next); 2566 } 2567 2568 if (n) 2569 break; 2570 2571 if (++state->bucket >= (1 << nht->hash_shift)) 2572 break; 2573 2574 n = rcu_dereference_bh(nht->hash_buckets[state->bucket]); 2575 } 2576 2577 if (n && pos) 2578 --(*pos); 2579 return n; 2580} 2581 2582static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos) 2583{ 2584 struct neighbour *n = neigh_get_first(seq); 2585 2586 if (n) { 2587 --(*pos); 2588 while (*pos) { 2589 n = neigh_get_next(seq, n, pos); 2590 if (!n) 2591 break; 2592 } 2593 } 2594 return *pos ? NULL : n; 2595} 2596 2597static struct pneigh_entry *pneigh_get_first(struct seq_file *seq) 2598{ 2599 struct neigh_seq_state *state = seq->private; 2600 struct net *net = seq_file_net(seq); 2601 struct neigh_table *tbl = state->tbl; 2602 struct pneigh_entry *pn = NULL; 2603 int bucket = state->bucket; 2604 2605 state->flags |= NEIGH_SEQ_IS_PNEIGH; 2606 for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) { 2607 pn = tbl->phash_buckets[bucket]; 2608 while (pn && !net_eq(pneigh_net(pn), net)) 2609 pn = pn->next; 2610 if (pn) 2611 break; 2612 } 2613 state->bucket = bucket; 2614 2615 return pn; 2616} 2617 2618static struct pneigh_entry *pneigh_get_next(struct seq_file *seq, 2619 struct pneigh_entry *pn, 2620 loff_t *pos) 2621{ 2622 struct neigh_seq_state *state = seq->private; 2623 struct net *net = seq_file_net(seq); 2624 struct neigh_table *tbl = state->tbl; 2625 2626 do { 2627 pn = pn->next; 2628 } while (pn && !net_eq(pneigh_net(pn), net)); 2629 2630 while (!pn) { 2631 if (++state->bucket > PNEIGH_HASHMASK) 2632 break; 2633 pn = tbl->phash_buckets[state->bucket]; 2634 while (pn && !net_eq(pneigh_net(pn), net)) 2635 pn = pn->next; 2636 if (pn) 2637 break; 2638 } 2639 2640 if (pn && pos) 2641 --(*pos); 2642 2643 return pn; 2644} 2645 2646static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos) 2647{ 2648 struct pneigh_entry *pn = pneigh_get_first(seq); 2649 2650 if (pn) { 2651 --(*pos); 2652 while (*pos) { 2653 pn = pneigh_get_next(seq, pn, pos); 2654 if (!pn) 2655 break; 2656 } 2657 } 2658 return *pos ? NULL : pn; 2659} 2660 2661static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos) 2662{ 2663 struct neigh_seq_state *state = seq->private; 2664 void *rc; 2665 loff_t idxpos = *pos; 2666 2667 rc = neigh_get_idx(seq, &idxpos); 2668 if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY)) 2669 rc = pneigh_get_idx(seq, &idxpos); 2670 2671 return rc; 2672} 2673 2674void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags) 2675 __acquires(rcu_bh) 2676{ 2677 struct neigh_seq_state *state = seq->private; 2678 2679 state->tbl = tbl; 2680 state->bucket = 0; 2681 state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH); 2682 2683 rcu_read_lock_bh(); 2684 state->nht = rcu_dereference_bh(tbl->nht); 2685 2686 return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN; 2687} 2688EXPORT_SYMBOL(neigh_seq_start); 2689 2690void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2691{ 2692 struct neigh_seq_state *state; 2693 void *rc; 2694 2695 if (v == SEQ_START_TOKEN) { 2696 rc = neigh_get_first(seq); 2697 goto out; 2698 } 2699 2700 state = seq->private; 2701 if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) { 2702 rc = neigh_get_next(seq, v, NULL); 2703 if (rc) 2704 goto out; 2705 if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY)) 2706 rc = pneigh_get_first(seq); 2707 } else { 2708 BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY); 2709 rc = pneigh_get_next(seq, v, NULL); 2710 } 2711out: 2712 ++(*pos); 2713 return rc; 2714} 2715EXPORT_SYMBOL(neigh_seq_next); 2716 2717void neigh_seq_stop(struct seq_file *seq, void *v) 2718 __releases(rcu_bh) 2719{ 2720 rcu_read_unlock_bh(); 2721} 2722EXPORT_SYMBOL(neigh_seq_stop); 2723 2724/* statistics via seq_file */ 2725 2726static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos) 2727{ 2728 struct neigh_table *tbl = seq->private; 2729 int cpu; 2730 2731 if (*pos == 0) 2732 return SEQ_START_TOKEN; 2733 2734 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) { 2735 if (!cpu_possible(cpu)) 2736 continue; 2737 *pos = cpu+1; 2738 return per_cpu_ptr(tbl->stats, cpu); 2739 } 2740 return NULL; 2741} 2742 2743static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2744{ 2745 struct neigh_table *tbl = seq->private; 2746 int cpu; 2747 2748 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) { 2749 if (!cpu_possible(cpu)) 2750 continue; 2751 *pos = cpu+1; 2752 return per_cpu_ptr(tbl->stats, cpu); 2753 } 2754 return NULL; 2755} 2756 2757static void neigh_stat_seq_stop(struct seq_file *seq, void *v) 2758{ 2759 2760} 2761 2762static int neigh_stat_seq_show(struct seq_file *seq, void *v) 2763{ 2764 struct neigh_table *tbl = seq->private; 2765 struct neigh_statistics *st = v; 2766 2767 if (v == SEQ_START_TOKEN) { 2768 seq_printf(seq, "entries allocs destroys hash_grows lookups hits res_failed rcv_probes_mcast rcv_probes_ucast periodic_gc_runs forced_gc_runs unresolved_discards table_fulls\n"); 2769 return 0; 2770 } 2771 2772 seq_printf(seq, "%08x %08lx %08lx %08lx %08lx %08lx %08lx " 2773 "%08lx %08lx %08lx %08lx %08lx %08lx\n", 2774 atomic_read(&tbl->entries), 2775 2776 st->allocs, 2777 st->destroys, 2778 st->hash_grows, 2779 2780 st->lookups, 2781 st->hits, 2782 2783 st->res_failed, 2784 2785 st->rcv_probes_mcast, 2786 st->rcv_probes_ucast, 2787 2788 st->periodic_gc_runs, 2789 st->forced_gc_runs, 2790 st->unres_discards, 2791 st->table_fulls 2792 ); 2793 2794 return 0; 2795} 2796 2797static const struct seq_operations neigh_stat_seq_ops = { 2798 .start = neigh_stat_seq_start, 2799 .next = neigh_stat_seq_next, 2800 .stop = neigh_stat_seq_stop, 2801 .show = neigh_stat_seq_show, 2802}; 2803 2804static int neigh_stat_seq_open(struct inode *inode, struct file *file) 2805{ 2806 int ret = seq_open(file, &neigh_stat_seq_ops); 2807 2808 if (!ret) { 2809 struct seq_file *sf = file->private_data; 2810 sf->private = PDE_DATA(inode); 2811 } 2812 return ret; 2813}; 2814 2815static const struct file_operations neigh_stat_seq_fops = { 2816 .owner = THIS_MODULE, 2817 .open = neigh_stat_seq_open, 2818 .read = seq_read, 2819 .llseek = seq_lseek, 2820 .release = seq_release, 2821}; 2822 2823#endif /* CONFIG_PROC_FS */ 2824 2825static inline size_t neigh_nlmsg_size(void) 2826{ 2827 return NLMSG_ALIGN(sizeof(struct ndmsg)) 2828 + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */ 2829 + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */ 2830 + nla_total_size(sizeof(struct nda_cacheinfo)) 2831 + nla_total_size(4); /* NDA_PROBES */ 2832} 2833 2834static void __neigh_notify(struct neighbour *n, int type, int flags) 2835{ 2836 struct net *net = dev_net(n->dev); 2837 struct sk_buff *skb; 2838 int err = -ENOBUFS; 2839 2840 skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC); 2841 if (skb == NULL) 2842 goto errout; 2843 2844 err = neigh_fill_info(skb, n, 0, 0, type, flags); 2845 if (err < 0) { 2846 /* -EMSGSIZE implies BUG in neigh_nlmsg_size() */ 2847 WARN_ON(err == -EMSGSIZE); 2848 kfree_skb(skb); 2849 goto errout; 2850 } 2851 rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC); 2852 return; 2853errout: 2854 if (err < 0) 2855 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err); 2856} 2857 2858void neigh_app_ns(struct neighbour *n) 2859{ 2860 __neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST); 2861} 2862EXPORT_SYMBOL(neigh_app_ns); 2863 2864#ifdef CONFIG_SYSCTL 2865static int zero; 2866static int int_max = INT_MAX; 2867static int unres_qlen_max = INT_MAX / SKB_TRUESIZE(ETH_FRAME_LEN); 2868 2869static int proc_unres_qlen(struct ctl_table *ctl, int write, 2870 void __user *buffer, size_t *lenp, loff_t *ppos) 2871{ 2872 int size, ret; 2873 struct ctl_table tmp = *ctl; 2874 2875 tmp.extra1 = &zero; 2876 tmp.extra2 = &unres_qlen_max; 2877 tmp.data = &size; 2878 2879 size = *(int *)ctl->data / SKB_TRUESIZE(ETH_FRAME_LEN); 2880 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); 2881 2882 if (write && !ret) 2883 *(int *)ctl->data = size * SKB_TRUESIZE(ETH_FRAME_LEN); 2884 return ret; 2885} 2886 2887static struct neigh_parms *neigh_get_dev_parms_rcu(struct net_device *dev, 2888 int family) 2889{ 2890 switch (family) { 2891 case AF_INET: 2892 return __in_dev_arp_parms_get_rcu(dev); 2893 case AF_INET6: 2894 return __in6_dev_nd_parms_get_rcu(dev); 2895 } 2896 return NULL; 2897} 2898 2899static void neigh_copy_dflt_parms(struct net *net, struct neigh_parms *p, 2900 int index) 2901{ 2902 struct net_device *dev; 2903 int family = neigh_parms_family(p); 2904 2905 rcu_read_lock(); 2906 for_each_netdev_rcu(net, dev) { 2907 struct neigh_parms *dst_p = 2908 neigh_get_dev_parms_rcu(dev, family); 2909 2910 if (dst_p && !test_bit(index, dst_p->data_state)) 2911 dst_p->data[index] = p->data[index]; 2912 } 2913 rcu_read_unlock(); 2914} 2915 2916static void neigh_proc_update(struct ctl_table *ctl, int write) 2917{ 2918 struct net_device *dev = ctl->extra1; 2919 struct neigh_parms *p = ctl->extra2; 2920 struct net *net = neigh_parms_net(p); 2921 int index = (int *) ctl->data - p->data; 2922 2923 if (!write) 2924 return; 2925 2926 set_bit(index, p->data_state); 2927 if (!dev) /* NULL dev means this is default value */ 2928 neigh_copy_dflt_parms(net, p, index); 2929} 2930 2931static int neigh_proc_dointvec_zero_intmax(struct ctl_table *ctl, int write, 2932 void __user *buffer, 2933 size_t *lenp, loff_t *ppos) 2934{ 2935 struct ctl_table tmp = *ctl; 2936 int ret; 2937 2938 tmp.extra1 = &zero; 2939 tmp.extra2 = &int_max; 2940 2941 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); 2942 neigh_proc_update(ctl, write); 2943 return ret; 2944} 2945 2946int neigh_proc_dointvec(struct ctl_table *ctl, int write, 2947 void __user *buffer, size_t *lenp, loff_t *ppos) 2948{ 2949 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos); 2950 2951 neigh_proc_update(ctl, write); 2952 return ret; 2953} 2954EXPORT_SYMBOL(neigh_proc_dointvec); 2955 2956int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write, 2957 void __user *buffer, 2958 size_t *lenp, loff_t *ppos) 2959{ 2960 int ret = proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos); 2961 2962 neigh_proc_update(ctl, write); 2963 return ret; 2964} 2965EXPORT_SYMBOL(neigh_proc_dointvec_jiffies); 2966 2967static int neigh_proc_dointvec_userhz_jiffies(struct ctl_table *ctl, int write, 2968 void __user *buffer, 2969 size_t *lenp, loff_t *ppos) 2970{ 2971 int ret = proc_dointvec_userhz_jiffies(ctl, write, buffer, lenp, ppos); 2972 2973 neigh_proc_update(ctl, write); 2974 return ret; 2975} 2976 2977int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write, 2978 void __user *buffer, 2979 size_t *lenp, loff_t *ppos) 2980{ 2981 int ret = proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos); 2982 2983 neigh_proc_update(ctl, write); 2984 return ret; 2985} 2986EXPORT_SYMBOL(neigh_proc_dointvec_ms_jiffies); 2987 2988static int neigh_proc_dointvec_unres_qlen(struct ctl_table *ctl, int write, 2989 void __user *buffer, 2990 size_t *lenp, loff_t *ppos) 2991{ 2992 int ret = proc_unres_qlen(ctl, write, buffer, lenp, ppos); 2993 2994 neigh_proc_update(ctl, write); 2995 return ret; 2996} 2997 2998static int neigh_proc_base_reachable_time(struct ctl_table *ctl, int write, 2999 void __user *buffer, 3000 size_t *lenp, loff_t *ppos) 3001{ 3002 struct neigh_parms *p = ctl->extra2; 3003 int ret; 3004 3005 if (strcmp(ctl->procname, "base_reachable_time") == 0) 3006 ret = neigh_proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos); 3007 else if (strcmp(ctl->procname, "base_reachable_time_ms") == 0) 3008 ret = neigh_proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos); 3009 else 3010 ret = -1; 3011 3012 if (write && ret == 0) { 3013 /* update reachable_time as well, otherwise, the change will 3014 * only be effective after the next time neigh_periodic_work 3015 * decides to recompute it 3016 */ 3017 p->reachable_time = 3018 neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME)); 3019 } 3020 return ret; 3021} 3022 3023#define NEIGH_PARMS_DATA_OFFSET(index) \ 3024 (&((struct neigh_parms *) 0)->data[index]) 3025 3026#define NEIGH_SYSCTL_ENTRY(attr, data_attr, name, mval, proc) \ 3027 [NEIGH_VAR_ ## attr] = { \ 3028 .procname = name, \ 3029 .data = NEIGH_PARMS_DATA_OFFSET(NEIGH_VAR_ ## data_attr), \ 3030 .maxlen = sizeof(int), \ 3031 .mode = mval, \ 3032 .proc_handler = proc, \ 3033 } 3034 3035#define NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(attr, name) \ 3036 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_zero_intmax) 3037 3038#define NEIGH_SYSCTL_JIFFIES_ENTRY(attr, name) \ 3039 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_jiffies) 3040 3041#define NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(attr, name) \ 3042 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_userhz_jiffies) 3043 3044#define NEIGH_SYSCTL_MS_JIFFIES_ENTRY(attr, name) \ 3045 NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_ms_jiffies) 3046 3047#define NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(attr, data_attr, name) \ 3048 NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_ms_jiffies) 3049 3050#define NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(attr, data_attr, name) \ 3051 NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_unres_qlen) 3052 3053static struct neigh_sysctl_table { 3054 struct ctl_table_header *sysctl_header; 3055 struct ctl_table neigh_vars[NEIGH_VAR_MAX + 1]; 3056} neigh_sysctl_template __read_mostly = { 3057 .neigh_vars = { 3058 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_PROBES, "mcast_solicit"), 3059 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(UCAST_PROBES, "ucast_solicit"), 3060 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(APP_PROBES, "app_solicit"), 3061 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_REPROBES, "mcast_resolicit"), 3062 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(RETRANS_TIME, "retrans_time"), 3063 NEIGH_SYSCTL_JIFFIES_ENTRY(BASE_REACHABLE_TIME, "base_reachable_time"), 3064 NEIGH_SYSCTL_JIFFIES_ENTRY(DELAY_PROBE_TIME, "delay_first_probe_time"), 3065 NEIGH_SYSCTL_JIFFIES_ENTRY(GC_STALETIME, "gc_stale_time"), 3066 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(QUEUE_LEN_BYTES, "unres_qlen_bytes"), 3067 NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(PROXY_QLEN, "proxy_qlen"), 3068 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(ANYCAST_DELAY, "anycast_delay"), 3069 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(PROXY_DELAY, "proxy_delay"), 3070 NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(LOCKTIME, "locktime"), 3071 NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(QUEUE_LEN, QUEUE_LEN_BYTES, "unres_qlen"), 3072 NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(RETRANS_TIME_MS, RETRANS_TIME, "retrans_time_ms"), 3073 NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(BASE_REACHABLE_TIME_MS, BASE_REACHABLE_TIME, "base_reachable_time_ms"), 3074 [NEIGH_VAR_GC_INTERVAL] = { 3075 .procname = "gc_interval", 3076 .maxlen = sizeof(int), 3077 .mode = 0644, 3078 .proc_handler = proc_dointvec_jiffies, 3079 }, 3080 [NEIGH_VAR_GC_THRESH1] = { 3081 .procname = "gc_thresh1", 3082 .maxlen = sizeof(int), 3083 .mode = 0644, 3084 .extra1 = &zero, 3085 .extra2 = &int_max, 3086 .proc_handler = proc_dointvec_minmax, 3087 }, 3088 [NEIGH_VAR_GC_THRESH2] = { 3089 .procname = "gc_thresh2", 3090 .maxlen = sizeof(int), 3091 .mode = 0644, 3092 .extra1 = &zero, 3093 .extra2 = &int_max, 3094 .proc_handler = proc_dointvec_minmax, 3095 }, 3096 [NEIGH_VAR_GC_THRESH3] = { 3097 .procname = "gc_thresh3", 3098 .maxlen = sizeof(int), 3099 .mode = 0644, 3100 .extra1 = &zero, 3101 .extra2 = &int_max, 3102 .proc_handler = proc_dointvec_minmax, 3103 }, 3104 {}, 3105 }, 3106}; 3107 3108int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p, 3109 proc_handler *handler) 3110{ 3111 int i; 3112 struct neigh_sysctl_table *t; 3113 const char *dev_name_source; 3114 char neigh_path[ sizeof("net//neigh/") + IFNAMSIZ + IFNAMSIZ ]; 3115 char *p_name; 3116 3117 t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL); 3118 if (!t) 3119 goto err; 3120 3121 for (i = 0; i < NEIGH_VAR_GC_INTERVAL; i++) { 3122 t->neigh_vars[i].data += (long) p; 3123 t->neigh_vars[i].extra1 = dev; 3124 t->neigh_vars[i].extra2 = p; 3125 } 3126 3127 if (dev) { 3128 dev_name_source = dev->name; 3129 /* Terminate the table early */ 3130 memset(&t->neigh_vars[NEIGH_VAR_GC_INTERVAL], 0, 3131 sizeof(t->neigh_vars[NEIGH_VAR_GC_INTERVAL])); 3132 } else { 3133 struct neigh_table *tbl = p->tbl; 3134 dev_name_source = "default"; 3135 t->neigh_vars[NEIGH_VAR_GC_INTERVAL].data = &tbl->gc_interval; 3136 t->neigh_vars[NEIGH_VAR_GC_THRESH1].data = &tbl->gc_thresh1; 3137 t->neigh_vars[NEIGH_VAR_GC_THRESH2].data = &tbl->gc_thresh2; 3138 t->neigh_vars[NEIGH_VAR_GC_THRESH3].data = &tbl->gc_thresh3; 3139 } 3140 3141 if (handler) { 3142 /* RetransTime */ 3143 t->neigh_vars[NEIGH_VAR_RETRANS_TIME].proc_handler = handler; 3144 /* ReachableTime */ 3145 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler = handler; 3146 /* RetransTime (in milliseconds)*/ 3147 t->neigh_vars[NEIGH_VAR_RETRANS_TIME_MS].proc_handler = handler; 3148 /* ReachableTime (in milliseconds) */ 3149 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler = handler; 3150 } else { 3151 /* Those handlers will update p->reachable_time after 3152 * base_reachable_time(_ms) is set to ensure the new timer starts being 3153 * applied after the next neighbour update instead of waiting for 3154 * neigh_periodic_work to update its value (can be multiple minutes) 3155 * So any handler that replaces them should do this as well 3156 */ 3157 /* ReachableTime */ 3158 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler = 3159 neigh_proc_base_reachable_time; 3160 /* ReachableTime (in milliseconds) */ 3161 t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler = 3162 neigh_proc_base_reachable_time; 3163 } 3164 3165 /* Don't export sysctls to unprivileged users */ 3166 if (neigh_parms_net(p)->user_ns != &init_user_ns) 3167 t->neigh_vars[0].procname = NULL; 3168 3169 switch (neigh_parms_family(p)) { 3170 case AF_INET: 3171 p_name = "ipv4"; 3172 break; 3173 case AF_INET6: 3174 p_name = "ipv6"; 3175 break; 3176 default: 3177 BUG(); 3178 } 3179 3180 snprintf(neigh_path, sizeof(neigh_path), "net/%s/neigh/%s", 3181 p_name, dev_name_source); 3182 t->sysctl_header = 3183 register_net_sysctl(neigh_parms_net(p), neigh_path, t->neigh_vars); 3184 if (!t->sysctl_header) 3185 goto free; 3186 3187 p->sysctl_table = t; 3188 return 0; 3189 3190free: 3191 kfree(t); 3192err: 3193 return -ENOBUFS; 3194} 3195EXPORT_SYMBOL(neigh_sysctl_register); 3196 3197void neigh_sysctl_unregister(struct neigh_parms *p) 3198{ 3199 if (p->sysctl_table) { 3200 struct neigh_sysctl_table *t = p->sysctl_table; 3201 p->sysctl_table = NULL; 3202 unregister_net_sysctl_table(t->sysctl_header); 3203 kfree(t); 3204 } 3205} 3206EXPORT_SYMBOL(neigh_sysctl_unregister); 3207 3208#endif /* CONFIG_SYSCTL */ 3209 3210static int __init neigh_init(void) 3211{ 3212 rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL, NULL); 3213 rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL, NULL); 3214 rtnl_register(PF_UNSPEC, RTM_GETNEIGH, NULL, neigh_dump_info, NULL); 3215 3216 rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info, 3217 NULL); 3218 rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL, NULL); 3219 3220 return 0; 3221} 3222 3223subsys_initcall(neigh_init); 3224 3225