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v4.6
 
   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
v6.2
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *	Generic address resolution entity
   4 *
   5 *	Authors:
   6 *	Pedro Roque		<roque@di.fc.ul.pt>
   7 *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
   8 *
 
 
 
 
 
   9 *	Fixes:
  10 *	Vitaly E. Lavrov	releasing NULL neighbor in neigh_add.
  11 *	Harald Welte		Add neighbour cache statistics like rtstat
  12 */
  13
  14#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  15
  16#include <linux/slab.h>
  17#include <linux/kmemleak.h>
  18#include <linux/types.h>
  19#include <linux/kernel.h>
  20#include <linux/module.h>
  21#include <linux/socket.h>
  22#include <linux/netdevice.h>
  23#include <linux/proc_fs.h>
  24#ifdef CONFIG_SYSCTL
  25#include <linux/sysctl.h>
  26#endif
  27#include <linux/times.h>
  28#include <net/net_namespace.h>
  29#include <net/neighbour.h>
  30#include <net/arp.h>
  31#include <net/dst.h>
  32#include <net/sock.h>
  33#include <net/netevent.h>
  34#include <net/netlink.h>
  35#include <linux/rtnetlink.h>
  36#include <linux/random.h>
  37#include <linux/string.h>
  38#include <linux/log2.h>
  39#include <linux/inetdevice.h>
  40#include <net/addrconf.h>
  41
  42#include <trace/events/neigh.h>
  43
  44#define NEIGH_DEBUG 1
  45#define neigh_dbg(level, fmt, ...)		\
  46do {						\
  47	if (level <= NEIGH_DEBUG)		\
  48		pr_debug(fmt, ##__VA_ARGS__);	\
  49} while (0)
  50
  51#define PNEIGH_HASHMASK		0xF
  52
  53static void neigh_timer_handler(struct timer_list *t);
  54static void __neigh_notify(struct neighbour *n, int type, int flags,
  55			   u32 pid);
  56static void neigh_update_notify(struct neighbour *neigh, u32 nlmsg_pid);
  57static int pneigh_ifdown_and_unlock(struct neigh_table *tbl,
  58				    struct net_device *dev);
  59
  60#ifdef CONFIG_PROC_FS
  61static const struct seq_operations neigh_stat_seq_ops;
  62#endif
  63
  64/*
  65   Neighbour hash table buckets are protected with rwlock tbl->lock.
  66
  67   - All the scans/updates to hash buckets MUST be made under this lock.
  68   - NOTHING clever should be made under this lock: no callbacks
  69     to protocol backends, no attempts to send something to network.
  70     It will result in deadlocks, if backend/driver wants to use neighbour
  71     cache.
  72   - If the entry requires some non-trivial actions, increase
  73     its reference count and release table lock.
  74
  75   Neighbour entries are protected:
  76   - with reference count.
  77   - with rwlock neigh->lock
  78
  79   Reference count prevents destruction.
  80
  81   neigh->lock mainly serializes ll address data and its validity state.
  82   However, the same lock is used to protect another entry fields:
  83    - timer
  84    - resolution queue
  85
  86   Again, nothing clever shall be made under neigh->lock,
  87   the most complicated procedure, which we allow is dev->hard_header.
  88   It is supposed, that dev->hard_header is simplistic and does
  89   not make callbacks to neighbour tables.
  90 */
  91
  92static int neigh_blackhole(struct neighbour *neigh, struct sk_buff *skb)
  93{
  94	kfree_skb(skb);
  95	return -ENETDOWN;
  96}
  97
  98static void neigh_cleanup_and_release(struct neighbour *neigh)
  99{
 100	trace_neigh_cleanup_and_release(neigh, 0);
 101	__neigh_notify(neigh, RTM_DELNEIGH, 0, 0);
 102	call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
 
 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 ? get_random_u32_below(base) + (base >> 1) : 0;
 115}
 116EXPORT_SYMBOL(neigh_rand_reach_time);
 117
 118static void neigh_mark_dead(struct neighbour *n)
 119{
 120	n->dead = 1;
 121	if (!list_empty(&n->gc_list)) {
 122		list_del_init(&n->gc_list);
 123		atomic_dec(&n->tbl->gc_entries);
 124	}
 125	if (!list_empty(&n->managed_list))
 126		list_del_init(&n->managed_list);
 127}
 128
 129static void neigh_update_gc_list(struct neighbour *n)
 130{
 131	bool on_gc_list, exempt_from_gc;
 132
 133	write_lock_bh(&n->tbl->lock);
 134	write_lock(&n->lock);
 135	if (n->dead)
 136		goto out;
 137
 138	/* remove from the gc list if new state is permanent or if neighbor
 139	 * is externally learned; otherwise entry should be on the gc list
 140	 */
 141	exempt_from_gc = n->nud_state & NUD_PERMANENT ||
 142			 n->flags & NTF_EXT_LEARNED;
 143	on_gc_list = !list_empty(&n->gc_list);
 144
 145	if (exempt_from_gc && on_gc_list) {
 146		list_del_init(&n->gc_list);
 147		atomic_dec(&n->tbl->gc_entries);
 148	} else if (!exempt_from_gc && !on_gc_list) {
 149		/* add entries to the tail; cleaning removes from the front */
 150		list_add_tail(&n->gc_list, &n->tbl->gc_list);
 151		atomic_inc(&n->tbl->gc_entries);
 152	}
 153out:
 154	write_unlock(&n->lock);
 155	write_unlock_bh(&n->tbl->lock);
 156}
 157
 158static void neigh_update_managed_list(struct neighbour *n)
 159{
 160	bool on_managed_list, add_to_managed;
 161
 162	write_lock_bh(&n->tbl->lock);
 163	write_lock(&n->lock);
 164	if (n->dead)
 165		goto out;
 166
 167	add_to_managed = n->flags & NTF_MANAGED;
 168	on_managed_list = !list_empty(&n->managed_list);
 169
 170	if (!add_to_managed && on_managed_list)
 171		list_del_init(&n->managed_list);
 172	else if (add_to_managed && !on_managed_list)
 173		list_add_tail(&n->managed_list, &n->tbl->managed_list);
 174out:
 175	write_unlock(&n->lock);
 176	write_unlock_bh(&n->tbl->lock);
 177}
 178
 179static void neigh_update_flags(struct neighbour *neigh, u32 flags, int *notify,
 180			       bool *gc_update, bool *managed_update)
 181{
 182	u32 ndm_flags, old_flags = neigh->flags;
 183
 184	if (!(flags & NEIGH_UPDATE_F_ADMIN))
 185		return;
 186
 187	ndm_flags  = (flags & NEIGH_UPDATE_F_EXT_LEARNED) ? NTF_EXT_LEARNED : 0;
 188	ndm_flags |= (flags & NEIGH_UPDATE_F_MANAGED) ? NTF_MANAGED : 0;
 189
 190	if ((old_flags ^ ndm_flags) & NTF_EXT_LEARNED) {
 191		if (ndm_flags & NTF_EXT_LEARNED)
 192			neigh->flags |= NTF_EXT_LEARNED;
 193		else
 194			neigh->flags &= ~NTF_EXT_LEARNED;
 195		*notify = 1;
 196		*gc_update = true;
 197	}
 198	if ((old_flags ^ ndm_flags) & NTF_MANAGED) {
 199		if (ndm_flags & NTF_MANAGED)
 200			neigh->flags |= NTF_MANAGED;
 201		else
 202			neigh->flags &= ~NTF_MANAGED;
 203		*notify = 1;
 204		*managed_update = true;
 205	}
 206}
 207
 208static bool neigh_del(struct neighbour *n, struct neighbour __rcu **np,
 209		      struct neigh_table *tbl)
 210{
 211	bool retval = false;
 212
 213	write_lock(&n->lock);
 214	if (refcount_read(&n->refcnt) == 1) {
 215		struct neighbour *neigh;
 216
 217		neigh = rcu_dereference_protected(n->next,
 218						  lockdep_is_held(&tbl->lock));
 219		rcu_assign_pointer(*np, neigh);
 220		neigh_mark_dead(n);
 221		retval = true;
 222	}
 223	write_unlock(&n->lock);
 224	if (retval)
 225		neigh_cleanup_and_release(n);
 226	return retval;
 227}
 228
 229bool neigh_remove_one(struct neighbour *ndel, struct neigh_table *tbl)
 230{
 231	struct neigh_hash_table *nht;
 232	void *pkey = ndel->primary_key;
 233	u32 hash_val;
 234	struct neighbour *n;
 235	struct neighbour __rcu **np;
 236
 237	nht = rcu_dereference_protected(tbl->nht,
 238					lockdep_is_held(&tbl->lock));
 239	hash_val = tbl->hash(pkey, ndel->dev, nht->hash_rnd);
 240	hash_val = hash_val >> (32 - nht->hash_shift);
 241
 242	np = &nht->hash_buckets[hash_val];
 243	while ((n = rcu_dereference_protected(*np,
 244					      lockdep_is_held(&tbl->lock)))) {
 245		if (n == ndel)
 246			return neigh_del(n, np, tbl);
 247		np = &n->next;
 248	}
 249	return false;
 250}
 251
 252static int neigh_forced_gc(struct neigh_table *tbl)
 253{
 254	int max_clean = atomic_read(&tbl->gc_entries) - tbl->gc_thresh2;
 255	unsigned long tref = jiffies - 5 * HZ;
 256	struct neighbour *n, *tmp;
 257	int shrunk = 0;
 
 
 258
 259	NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
 260
 261	write_lock_bh(&tbl->lock);
 
 
 
 
 
 262
 263	list_for_each_entry_safe(n, tmp, &tbl->gc_list, gc_list) {
 264		if (refcount_read(&n->refcnt) == 1) {
 265			bool remove = false;
 266
 
 
 
 267			write_lock(&n->lock);
 268			if ((n->nud_state == NUD_FAILED) ||
 269			    (n->nud_state == NUD_NOARP) ||
 270			    (tbl->is_multicast &&
 271			     tbl->is_multicast(n->primary_key)) ||
 272			    !time_in_range(n->updated, tref, jiffies))
 273				remove = true;
 
 
 
 
 
 274			write_unlock(&n->lock);
 275
 276			if (remove && neigh_remove_one(n, tbl))
 277				shrunk++;
 278			if (shrunk >= max_clean)
 279				break;
 280		}
 281	}
 282
 283	tbl->last_flush = jiffies;
 284
 285	write_unlock_bh(&tbl->lock);
 286
 287	return shrunk;
 288}
 289
 290static void neigh_add_timer(struct neighbour *n, unsigned long when)
 291{
 292	/* Use safe distance from the jiffies - LONG_MAX point while timer
 293	 * is running in DELAY/PROBE state but still show to user space
 294	 * large times in the past.
 295	 */
 296	unsigned long mint = jiffies - (LONG_MAX - 86400 * HZ);
 297
 298	neigh_hold(n);
 299	if (!time_in_range(n->confirmed, mint, jiffies))
 300		n->confirmed = mint;
 301	if (time_before(n->used, n->confirmed))
 302		n->used = n->confirmed;
 303	if (unlikely(mod_timer(&n->timer, when))) {
 304		printk("NEIGH: BUG, double timer add, state is %x\n",
 305		       n->nud_state);
 306		dump_stack();
 307	}
 308}
 309
 310static int neigh_del_timer(struct neighbour *n)
 311{
 312	if ((n->nud_state & NUD_IN_TIMER) &&
 313	    del_timer(&n->timer)) {
 314		neigh_release(n);
 315		return 1;
 316	}
 317	return 0;
 318}
 319
 320static struct neigh_parms *neigh_get_dev_parms_rcu(struct net_device *dev,
 321						   int family)
 322{
 323	switch (family) {
 324	case AF_INET:
 325		return __in_dev_arp_parms_get_rcu(dev);
 326	case AF_INET6:
 327		return __in6_dev_nd_parms_get_rcu(dev);
 328	}
 329	return NULL;
 330}
 331
 332static void neigh_parms_qlen_dec(struct net_device *dev, int family)
 333{
 334	struct neigh_parms *p;
 335
 336	rcu_read_lock();
 337	p = neigh_get_dev_parms_rcu(dev, family);
 338	if (p)
 339		p->qlen--;
 340	rcu_read_unlock();
 341}
 342
 343static void pneigh_queue_purge(struct sk_buff_head *list, struct net *net,
 344			       int family)
 345{
 346	struct sk_buff_head tmp;
 347	unsigned long flags;
 348	struct sk_buff *skb;
 349
 350	skb_queue_head_init(&tmp);
 351	spin_lock_irqsave(&list->lock, flags);
 352	skb = skb_peek(list);
 353	while (skb != NULL) {
 354		struct sk_buff *skb_next = skb_peek_next(skb, list);
 355		struct net_device *dev = skb->dev;
 356
 357		if (net == NULL || net_eq(dev_net(dev), net)) {
 358			neigh_parms_qlen_dec(dev, family);
 359			__skb_unlink(skb, list);
 360			__skb_queue_tail(&tmp, skb);
 361		}
 362		skb = skb_next;
 363	}
 364	spin_unlock_irqrestore(&list->lock, flags);
 365
 366	while ((skb = __skb_dequeue(&tmp))) {
 367		dev_put(skb->dev);
 368		kfree_skb(skb);
 369	}
 370}
 371
 372static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev,
 373			    bool skip_perm)
 374{
 375	int i;
 376	struct neigh_hash_table *nht;
 377
 378	nht = rcu_dereference_protected(tbl->nht,
 379					lockdep_is_held(&tbl->lock));
 380
 381	for (i = 0; i < (1 << nht->hash_shift); i++) {
 382		struct neighbour *n;
 383		struct neighbour __rcu **np = &nht->hash_buckets[i];
 384
 385		while ((n = rcu_dereference_protected(*np,
 386					lockdep_is_held(&tbl->lock))) != NULL) {
 387			if (dev && n->dev != dev) {
 388				np = &n->next;
 389				continue;
 390			}
 391			if (skip_perm && n->nud_state & NUD_PERMANENT) {
 392				np = &n->next;
 393				continue;
 394			}
 395			rcu_assign_pointer(*np,
 396				   rcu_dereference_protected(n->next,
 397						lockdep_is_held(&tbl->lock)));
 398			write_lock(&n->lock);
 399			neigh_del_timer(n);
 400			neigh_mark_dead(n);
 401			if (refcount_read(&n->refcnt) != 1) {
 
 402				/* The most unpleasant situation.
 403				   We must destroy neighbour entry,
 404				   but someone still uses it.
 405
 406				   The destroy will be delayed until
 407				   the last user releases us, but
 408				   we must kill timers etc. and move
 409				   it to safe state.
 410				 */
 411				__skb_queue_purge(&n->arp_queue);
 412				n->arp_queue_len_bytes = 0;
 413				n->output = neigh_blackhole;
 414				if (n->nud_state & NUD_VALID)
 415					n->nud_state = NUD_NOARP;
 416				else
 417					n->nud_state = NUD_NONE;
 418				neigh_dbg(2, "neigh %p is stray\n", n);
 419			}
 420			write_unlock(&n->lock);
 421			neigh_cleanup_and_release(n);
 422		}
 423	}
 424}
 425
 426void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
 427{
 428	write_lock_bh(&tbl->lock);
 429	neigh_flush_dev(tbl, dev, false);
 430	write_unlock_bh(&tbl->lock);
 431}
 432EXPORT_SYMBOL(neigh_changeaddr);
 433
 434static int __neigh_ifdown(struct neigh_table *tbl, struct net_device *dev,
 435			  bool skip_perm)
 436{
 437	write_lock_bh(&tbl->lock);
 438	neigh_flush_dev(tbl, dev, skip_perm);
 439	pneigh_ifdown_and_unlock(tbl, dev);
 440	pneigh_queue_purge(&tbl->proxy_queue, dev ? dev_net(dev) : NULL,
 441			   tbl->family);
 442	if (skb_queue_empty_lockless(&tbl->proxy_queue))
 443		del_timer_sync(&tbl->proxy_timer);
 444	return 0;
 445}
 446
 447int neigh_carrier_down(struct neigh_table *tbl, struct net_device *dev)
 448{
 449	__neigh_ifdown(tbl, dev, true);
 450	return 0;
 451}
 452EXPORT_SYMBOL(neigh_carrier_down);
 453
 454int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
 455{
 456	__neigh_ifdown(tbl, dev, false);
 457	return 0;
 458}
 459EXPORT_SYMBOL(neigh_ifdown);
 460
 461static struct neighbour *neigh_alloc(struct neigh_table *tbl,
 462				     struct net_device *dev,
 463				     u32 flags, bool exempt_from_gc)
 464{
 465	struct neighbour *n = NULL;
 466	unsigned long now = jiffies;
 467	int entries;
 468
 469	if (exempt_from_gc)
 470		goto do_alloc;
 471
 472	entries = atomic_inc_return(&tbl->gc_entries) - 1;
 473	if (entries >= tbl->gc_thresh3 ||
 474	    (entries >= tbl->gc_thresh2 &&
 475	     time_after(now, tbl->last_flush + 5 * HZ))) {
 476		if (!neigh_forced_gc(tbl) &&
 477		    entries >= tbl->gc_thresh3) {
 478			net_info_ratelimited("%s: neighbor table overflow!\n",
 479					     tbl->id);
 480			NEIGH_CACHE_STAT_INC(tbl, table_fulls);
 481			goto out_entries;
 482		}
 483	}
 484
 485do_alloc:
 486	n = kzalloc(tbl->entry_size + dev->neigh_priv_len, GFP_ATOMIC);
 487	if (!n)
 488		goto out_entries;
 489
 490	__skb_queue_head_init(&n->arp_queue);
 491	rwlock_init(&n->lock);
 492	seqlock_init(&n->ha_lock);
 493	n->updated	  = n->used = now;
 494	n->nud_state	  = NUD_NONE;
 495	n->output	  = neigh_blackhole;
 496	n->flags	  = flags;
 497	seqlock_init(&n->hh.hh_lock);
 498	n->parms	  = neigh_parms_clone(&tbl->parms);
 499	timer_setup(&n->timer, neigh_timer_handler, 0);
 500
 501	NEIGH_CACHE_STAT_INC(tbl, allocs);
 502	n->tbl		  = tbl;
 503	refcount_set(&n->refcnt, 1);
 504	n->dead		  = 1;
 505	INIT_LIST_HEAD(&n->gc_list);
 506	INIT_LIST_HEAD(&n->managed_list);
 507
 508	atomic_inc(&tbl->entries);
 509out:
 510	return n;
 511
 512out_entries:
 513	if (!exempt_from_gc)
 514		atomic_dec(&tbl->gc_entries);
 515	goto out;
 516}
 517
 518static void neigh_get_hash_rnd(u32 *x)
 519{
 520	*x = get_random_u32() | 1;
 
 521}
 522
 523static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
 524{
 525	size_t size = (1 << shift) * sizeof(struct neighbour *);
 526	struct neigh_hash_table *ret;
 527	struct neighbour __rcu **buckets;
 528	int i;
 529
 530	ret = kmalloc(sizeof(*ret), GFP_ATOMIC);
 531	if (!ret)
 532		return NULL;
 533	if (size <= PAGE_SIZE) {
 534		buckets = kzalloc(size, GFP_ATOMIC);
 535	} else {
 536		buckets = (struct neighbour __rcu **)
 537			  __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
 538					   get_order(size));
 539		kmemleak_alloc(buckets, size, 1, GFP_ATOMIC);
 540	}
 541	if (!buckets) {
 542		kfree(ret);
 543		return NULL;
 544	}
 545	ret->hash_buckets = buckets;
 546	ret->hash_shift = shift;
 547	for (i = 0; i < NEIGH_NUM_HASH_RND; i++)
 548		neigh_get_hash_rnd(&ret->hash_rnd[i]);
 549	return ret;
 550}
 551
 552static void neigh_hash_free_rcu(struct rcu_head *head)
 553{
 554	struct neigh_hash_table *nht = container_of(head,
 555						    struct neigh_hash_table,
 556						    rcu);
 557	size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *);
 558	struct neighbour __rcu **buckets = nht->hash_buckets;
 559
 560	if (size <= PAGE_SIZE) {
 561		kfree(buckets);
 562	} else {
 563		kmemleak_free(buckets);
 564		free_pages((unsigned long)buckets, get_order(size));
 565	}
 566	kfree(nht);
 567}
 568
 569static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
 570						unsigned long new_shift)
 571{
 572	unsigned int i, hash;
 573	struct neigh_hash_table *new_nht, *old_nht;
 574
 575	NEIGH_CACHE_STAT_INC(tbl, hash_grows);
 576
 577	old_nht = rcu_dereference_protected(tbl->nht,
 578					    lockdep_is_held(&tbl->lock));
 579	new_nht = neigh_hash_alloc(new_shift);
 580	if (!new_nht)
 581		return old_nht;
 582
 583	for (i = 0; i < (1 << old_nht->hash_shift); i++) {
 584		struct neighbour *n, *next;
 585
 586		for (n = rcu_dereference_protected(old_nht->hash_buckets[i],
 587						   lockdep_is_held(&tbl->lock));
 588		     n != NULL;
 589		     n = next) {
 590			hash = tbl->hash(n->primary_key, n->dev,
 591					 new_nht->hash_rnd);
 592
 593			hash >>= (32 - new_nht->hash_shift);
 594			next = rcu_dereference_protected(n->next,
 595						lockdep_is_held(&tbl->lock));
 596
 597			rcu_assign_pointer(n->next,
 598					   rcu_dereference_protected(
 599						new_nht->hash_buckets[hash],
 600						lockdep_is_held(&tbl->lock)));
 601			rcu_assign_pointer(new_nht->hash_buckets[hash], n);
 602		}
 603	}
 604
 605	rcu_assign_pointer(tbl->nht, new_nht);
 606	call_rcu(&old_nht->rcu, neigh_hash_free_rcu);
 607	return new_nht;
 608}
 609
 610struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
 611			       struct net_device *dev)
 612{
 613	struct neighbour *n;
 614
 615	NEIGH_CACHE_STAT_INC(tbl, lookups);
 616
 617	rcu_read_lock_bh();
 618	n = __neigh_lookup_noref(tbl, pkey, dev);
 619	if (n) {
 620		if (!refcount_inc_not_zero(&n->refcnt))
 621			n = NULL;
 622		NEIGH_CACHE_STAT_INC(tbl, hits);
 623	}
 624
 625	rcu_read_unlock_bh();
 626	return n;
 627}
 628EXPORT_SYMBOL(neigh_lookup);
 629
 630struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
 631				     const void *pkey)
 632{
 633	struct neighbour *n;
 634	unsigned int key_len = tbl->key_len;
 635	u32 hash_val;
 636	struct neigh_hash_table *nht;
 637
 638	NEIGH_CACHE_STAT_INC(tbl, lookups);
 639
 640	rcu_read_lock_bh();
 641	nht = rcu_dereference_bh(tbl->nht);
 642	hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) >> (32 - nht->hash_shift);
 643
 644	for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
 645	     n != NULL;
 646	     n = rcu_dereference_bh(n->next)) {
 647		if (!memcmp(n->primary_key, pkey, key_len) &&
 648		    net_eq(dev_net(n->dev), net)) {
 649			if (!refcount_inc_not_zero(&n->refcnt))
 650				n = NULL;
 651			NEIGH_CACHE_STAT_INC(tbl, hits);
 652			break;
 653		}
 654	}
 655
 656	rcu_read_unlock_bh();
 657	return n;
 658}
 659EXPORT_SYMBOL(neigh_lookup_nodev);
 660
 661static struct neighbour *
 662___neigh_create(struct neigh_table *tbl, const void *pkey,
 663		struct net_device *dev, u32 flags,
 664		bool exempt_from_gc, bool want_ref)
 665{
 666	u32 hash_val, key_len = tbl->key_len;
 667	struct neighbour *n1, *rc, *n;
 
 
 668	struct neigh_hash_table *nht;
 669	int error;
 670
 671	n = neigh_alloc(tbl, dev, flags, exempt_from_gc);
 672	trace_neigh_create(tbl, dev, pkey, n, exempt_from_gc);
 673	if (!n) {
 674		rc = ERR_PTR(-ENOBUFS);
 675		goto out;
 676	}
 677
 678	memcpy(n->primary_key, pkey, key_len);
 679	n->dev = dev;
 680	netdev_hold(dev, &n->dev_tracker, GFP_ATOMIC);
 681
 682	/* Protocol specific setup. */
 683	if (tbl->constructor &&	(error = tbl->constructor(n)) < 0) {
 684		rc = ERR_PTR(error);
 685		goto out_neigh_release;
 686	}
 687
 688	if (dev->netdev_ops->ndo_neigh_construct) {
 689		error = dev->netdev_ops->ndo_neigh_construct(dev, n);
 690		if (error < 0) {
 691			rc = ERR_PTR(error);
 692			goto out_neigh_release;
 693		}
 694	}
 695
 696	/* Device specific setup. */
 697	if (n->parms->neigh_setup &&
 698	    (error = n->parms->neigh_setup(n)) < 0) {
 699		rc = ERR_PTR(error);
 700		goto out_neigh_release;
 701	}
 702
 703	n->confirmed = jiffies - (NEIGH_VAR(n->parms, BASE_REACHABLE_TIME) << 1);
 704
 705	write_lock_bh(&tbl->lock);
 706	nht = rcu_dereference_protected(tbl->nht,
 707					lockdep_is_held(&tbl->lock));
 708
 709	if (atomic_read(&tbl->entries) > (1 << nht->hash_shift))
 710		nht = neigh_hash_grow(tbl, nht->hash_shift + 1);
 711
 712	hash_val = tbl->hash(n->primary_key, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
 713
 714	if (n->parms->dead) {
 715		rc = ERR_PTR(-EINVAL);
 716		goto out_tbl_unlock;
 717	}
 718
 719	for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val],
 720					    lockdep_is_held(&tbl->lock));
 721	     n1 != NULL;
 722	     n1 = rcu_dereference_protected(n1->next,
 723			lockdep_is_held(&tbl->lock))) {
 724		if (dev == n1->dev && !memcmp(n1->primary_key, n->primary_key, key_len)) {
 725			if (want_ref)
 726				neigh_hold(n1);
 727			rc = n1;
 728			goto out_tbl_unlock;
 729		}
 730	}
 731
 732	n->dead = 0;
 733	if (!exempt_from_gc)
 734		list_add_tail(&n->gc_list, &n->tbl->gc_list);
 735	if (n->flags & NTF_MANAGED)
 736		list_add_tail(&n->managed_list, &n->tbl->managed_list);
 737	if (want_ref)
 738		neigh_hold(n);
 739	rcu_assign_pointer(n->next,
 740			   rcu_dereference_protected(nht->hash_buckets[hash_val],
 741						     lockdep_is_held(&tbl->lock)));
 742	rcu_assign_pointer(nht->hash_buckets[hash_val], n);
 743	write_unlock_bh(&tbl->lock);
 744	neigh_dbg(2, "neigh %p is created\n", n);
 745	rc = n;
 746out:
 747	return rc;
 748out_tbl_unlock:
 749	write_unlock_bh(&tbl->lock);
 750out_neigh_release:
 751	if (!exempt_from_gc)
 752		atomic_dec(&tbl->gc_entries);
 753	neigh_release(n);
 754	goto out;
 755}
 756
 757struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
 758				 struct net_device *dev, bool want_ref)
 759{
 760	return ___neigh_create(tbl, pkey, dev, 0, false, want_ref);
 761}
 762EXPORT_SYMBOL(__neigh_create);
 763
 764static u32 pneigh_hash(const void *pkey, unsigned int key_len)
 765{
 766	u32 hash_val = *(u32 *)(pkey + key_len - 4);
 767	hash_val ^= (hash_val >> 16);
 768	hash_val ^= hash_val >> 8;
 769	hash_val ^= hash_val >> 4;
 770	hash_val &= PNEIGH_HASHMASK;
 771	return hash_val;
 772}
 773
 774static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n,
 775					      struct net *net,
 776					      const void *pkey,
 777					      unsigned int key_len,
 778					      struct net_device *dev)
 779{
 780	while (n) {
 781		if (!memcmp(n->key, pkey, key_len) &&
 782		    net_eq(pneigh_net(n), net) &&
 783		    (n->dev == dev || !n->dev))
 784			return n;
 785		n = n->next;
 786	}
 787	return NULL;
 788}
 789
 790struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
 791		struct net *net, const void *pkey, struct net_device *dev)
 792{
 793	unsigned int key_len = tbl->key_len;
 794	u32 hash_val = pneigh_hash(pkey, key_len);
 795
 796	return __pneigh_lookup_1(tbl->phash_buckets[hash_val],
 797				 net, pkey, key_len, dev);
 798}
 799EXPORT_SYMBOL_GPL(__pneigh_lookup);
 800
 801struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
 802				    struct net *net, const void *pkey,
 803				    struct net_device *dev, int creat)
 804{
 805	struct pneigh_entry *n;
 806	unsigned int key_len = tbl->key_len;
 807	u32 hash_val = pneigh_hash(pkey, key_len);
 808
 809	read_lock_bh(&tbl->lock);
 810	n = __pneigh_lookup_1(tbl->phash_buckets[hash_val],
 811			      net, pkey, key_len, dev);
 812	read_unlock_bh(&tbl->lock);
 813
 814	if (n || !creat)
 815		goto out;
 816
 817	ASSERT_RTNL();
 818
 819	n = kzalloc(sizeof(*n) + key_len, GFP_KERNEL);
 820	if (!n)
 821		goto out;
 822
 823	write_pnet(&n->net, net);
 824	memcpy(n->key, pkey, key_len);
 825	n->dev = dev;
 826	netdev_hold(dev, &n->dev_tracker, GFP_KERNEL);
 
 827
 828	if (tbl->pconstructor && tbl->pconstructor(n)) {
 829		netdev_put(dev, &n->dev_tracker);
 
 830		kfree(n);
 831		n = NULL;
 832		goto out;
 833	}
 834
 835	write_lock_bh(&tbl->lock);
 836	n->next = tbl->phash_buckets[hash_val];
 837	tbl->phash_buckets[hash_val] = n;
 838	write_unlock_bh(&tbl->lock);
 839out:
 840	return n;
 841}
 842EXPORT_SYMBOL(pneigh_lookup);
 843
 844
 845int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
 846		  struct net_device *dev)
 847{
 848	struct pneigh_entry *n, **np;
 849	unsigned int key_len = tbl->key_len;
 850	u32 hash_val = pneigh_hash(pkey, key_len);
 851
 852	write_lock_bh(&tbl->lock);
 853	for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
 854	     np = &n->next) {
 855		if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
 856		    net_eq(pneigh_net(n), net)) {
 857			*np = n->next;
 858			write_unlock_bh(&tbl->lock);
 859			if (tbl->pdestructor)
 860				tbl->pdestructor(n);
 861			netdev_put(n->dev, &n->dev_tracker);
 
 862			kfree(n);
 863			return 0;
 864		}
 865	}
 866	write_unlock_bh(&tbl->lock);
 867	return -ENOENT;
 868}
 869
 870static int pneigh_ifdown_and_unlock(struct neigh_table *tbl,
 871				    struct net_device *dev)
 872{
 873	struct pneigh_entry *n, **np, *freelist = NULL;
 874	u32 h;
 875
 876	for (h = 0; h <= PNEIGH_HASHMASK; h++) {
 877		np = &tbl->phash_buckets[h];
 878		while ((n = *np) != NULL) {
 879			if (!dev || n->dev == dev) {
 880				*np = n->next;
 881				n->next = freelist;
 882				freelist = n;
 
 
 
 883				continue;
 884			}
 885			np = &n->next;
 886		}
 887	}
 888	write_unlock_bh(&tbl->lock);
 889	while ((n = freelist)) {
 890		freelist = n->next;
 891		n->next = NULL;
 892		if (tbl->pdestructor)
 893			tbl->pdestructor(n);
 894		netdev_put(n->dev, &n->dev_tracker);
 895		kfree(n);
 896	}
 897	return -ENOENT;
 898}
 899
 900static void neigh_parms_destroy(struct neigh_parms *parms);
 901
 902static inline void neigh_parms_put(struct neigh_parms *parms)
 903{
 904	if (refcount_dec_and_test(&parms->refcnt))
 905		neigh_parms_destroy(parms);
 906}
 907
 908/*
 909 *	neighbour must already be out of the table;
 910 *
 911 */
 912void neigh_destroy(struct neighbour *neigh)
 913{
 914	struct net_device *dev = neigh->dev;
 915
 916	NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
 917
 918	if (!neigh->dead) {
 919		pr_warn("Destroying alive neighbour %p\n", neigh);
 920		dump_stack();
 921		return;
 922	}
 923
 924	if (neigh_del_timer(neigh))
 925		pr_warn("Impossible event\n");
 926
 927	write_lock_bh(&neigh->lock);
 928	__skb_queue_purge(&neigh->arp_queue);
 929	write_unlock_bh(&neigh->lock);
 930	neigh->arp_queue_len_bytes = 0;
 931
 932	if (dev->netdev_ops->ndo_neigh_destroy)
 933		dev->netdev_ops->ndo_neigh_destroy(dev, neigh);
 934
 935	netdev_put(dev, &neigh->dev_tracker);
 936	neigh_parms_put(neigh->parms);
 937
 938	neigh_dbg(2, "neigh %p is destroyed\n", neigh);
 939
 940	atomic_dec(&neigh->tbl->entries);
 941	kfree_rcu(neigh, rcu);
 942}
 943EXPORT_SYMBOL(neigh_destroy);
 944
 945/* Neighbour state is suspicious;
 946   disable fast path.
 947
 948   Called with write_locked neigh.
 949 */
 950static void neigh_suspect(struct neighbour *neigh)
 951{
 952	neigh_dbg(2, "neigh %p is suspected\n", neigh);
 953
 954	neigh->output = neigh->ops->output;
 955}
 956
 957/* Neighbour state is OK;
 958   enable fast path.
 959
 960   Called with write_locked neigh.
 961 */
 962static void neigh_connect(struct neighbour *neigh)
 963{
 964	neigh_dbg(2, "neigh %p is connected\n", neigh);
 965
 966	neigh->output = neigh->ops->connected_output;
 967}
 968
 969static void neigh_periodic_work(struct work_struct *work)
 970{
 971	struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work);
 972	struct neighbour *n;
 973	struct neighbour __rcu **np;
 974	unsigned int i;
 975	struct neigh_hash_table *nht;
 976
 977	NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
 978
 979	write_lock_bh(&tbl->lock);
 980	nht = rcu_dereference_protected(tbl->nht,
 981					lockdep_is_held(&tbl->lock));
 982
 983	/*
 984	 *	periodically recompute ReachableTime from random function
 985	 */
 986
 987	if (time_after(jiffies, tbl->last_rand + 300 * HZ)) {
 988		struct neigh_parms *p;
 989		tbl->last_rand = jiffies;
 990		list_for_each_entry(p, &tbl->parms_list, list)
 991			p->reachable_time =
 992				neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
 993	}
 994
 995	if (atomic_read(&tbl->entries) < tbl->gc_thresh1)
 996		goto out;
 997
 998	for (i = 0 ; i < (1 << nht->hash_shift); i++) {
 999		np = &nht->hash_buckets[i];
1000
1001		while ((n = rcu_dereference_protected(*np,
1002				lockdep_is_held(&tbl->lock))) != NULL) {
1003			unsigned int state;
1004
1005			write_lock(&n->lock);
1006
1007			state = n->nud_state;
1008			if ((state & (NUD_PERMANENT | NUD_IN_TIMER)) ||
1009			    (n->flags & NTF_EXT_LEARNED)) {
1010				write_unlock(&n->lock);
1011				goto next_elt;
1012			}
1013
1014			if (time_before(n->used, n->confirmed) &&
1015			    time_is_before_eq_jiffies(n->confirmed))
1016				n->used = n->confirmed;
1017
1018			if (refcount_read(&n->refcnt) == 1 &&
1019			    (state == NUD_FAILED ||
1020			     !time_in_range_open(jiffies, n->used,
1021						 n->used + NEIGH_VAR(n->parms, GC_STALETIME)))) {
1022				*np = n->next;
1023				neigh_mark_dead(n);
1024				write_unlock(&n->lock);
1025				neigh_cleanup_and_release(n);
1026				continue;
1027			}
1028			write_unlock(&n->lock);
1029
1030next_elt:
1031			np = &n->next;
1032		}
1033		/*
1034		 * It's fine to release lock here, even if hash table
1035		 * grows while we are preempted.
1036		 */
1037		write_unlock_bh(&tbl->lock);
1038		cond_resched();
1039		write_lock_bh(&tbl->lock);
1040		nht = rcu_dereference_protected(tbl->nht,
1041						lockdep_is_held(&tbl->lock));
1042	}
1043out:
1044	/* Cycle through all hash buckets every BASE_REACHABLE_TIME/2 ticks.
1045	 * ARP entry timeouts range from 1/2 BASE_REACHABLE_TIME to 3/2
1046	 * BASE_REACHABLE_TIME.
1047	 */
1048	queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
1049			      NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME) >> 1);
1050	write_unlock_bh(&tbl->lock);
1051}
1052
1053static __inline__ int neigh_max_probes(struct neighbour *n)
1054{
1055	struct neigh_parms *p = n->parms;
1056	return NEIGH_VAR(p, UCAST_PROBES) + NEIGH_VAR(p, APP_PROBES) +
1057	       (n->nud_state & NUD_PROBE ? NEIGH_VAR(p, MCAST_REPROBES) :
1058	        NEIGH_VAR(p, MCAST_PROBES));
1059}
1060
1061static void neigh_invalidate(struct neighbour *neigh)
1062	__releases(neigh->lock)
1063	__acquires(neigh->lock)
1064{
1065	struct sk_buff *skb;
1066
1067	NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
1068	neigh_dbg(2, "neigh %p is failed\n", neigh);
1069	neigh->updated = jiffies;
1070
1071	/* It is very thin place. report_unreachable is very complicated
1072	   routine. Particularly, it can hit the same neighbour entry!
1073
1074	   So that, we try to be accurate and avoid dead loop. --ANK
1075	 */
1076	while (neigh->nud_state == NUD_FAILED &&
1077	       (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1078		write_unlock(&neigh->lock);
1079		neigh->ops->error_report(neigh, skb);
1080		write_lock(&neigh->lock);
1081	}
1082	__skb_queue_purge(&neigh->arp_queue);
1083	neigh->arp_queue_len_bytes = 0;
1084}
1085
1086static void neigh_probe(struct neighbour *neigh)
1087	__releases(neigh->lock)
1088{
1089	struct sk_buff *skb = skb_peek_tail(&neigh->arp_queue);
1090	/* keep skb alive even if arp_queue overflows */
1091	if (skb)
1092		skb = skb_clone(skb, GFP_ATOMIC);
1093	write_unlock(&neigh->lock);
1094	if (neigh->ops->solicit)
1095		neigh->ops->solicit(neigh, skb);
1096	atomic_inc(&neigh->probes);
1097	consume_skb(skb);
1098}
1099
1100/* Called when a timer expires for a neighbour entry. */
1101
1102static void neigh_timer_handler(struct timer_list *t)
1103{
1104	unsigned long now, next;
1105	struct neighbour *neigh = from_timer(neigh, t, timer);
1106	unsigned int state;
1107	int notify = 0;
1108
1109	write_lock(&neigh->lock);
1110
1111	state = neigh->nud_state;
1112	now = jiffies;
1113	next = now + HZ;
1114
1115	if (!(state & NUD_IN_TIMER))
1116		goto out;
1117
1118	if (state & NUD_REACHABLE) {
1119		if (time_before_eq(now,
1120				   neigh->confirmed + neigh->parms->reachable_time)) {
1121			neigh_dbg(2, "neigh %p is still alive\n", neigh);
1122			next = neigh->confirmed + neigh->parms->reachable_time;
1123		} else if (time_before_eq(now,
1124					  neigh->used +
1125					  NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
1126			neigh_dbg(2, "neigh %p is delayed\n", neigh);
1127			neigh->nud_state = NUD_DELAY;
1128			neigh->updated = jiffies;
1129			neigh_suspect(neigh);
1130			next = now + NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME);
1131		} else {
1132			neigh_dbg(2, "neigh %p is suspected\n", neigh);
1133			neigh->nud_state = NUD_STALE;
1134			neigh->updated = jiffies;
1135			neigh_suspect(neigh);
1136			notify = 1;
1137		}
1138	} else if (state & NUD_DELAY) {
1139		if (time_before_eq(now,
1140				   neigh->confirmed +
1141				   NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
1142			neigh_dbg(2, "neigh %p is now reachable\n", neigh);
1143			neigh->nud_state = NUD_REACHABLE;
1144			neigh->updated = jiffies;
1145			neigh_connect(neigh);
1146			notify = 1;
1147			next = neigh->confirmed + neigh->parms->reachable_time;
1148		} else {
1149			neigh_dbg(2, "neigh %p is probed\n", neigh);
1150			neigh->nud_state = NUD_PROBE;
1151			neigh->updated = jiffies;
1152			atomic_set(&neigh->probes, 0);
1153			notify = 1;
1154			next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
1155					 HZ/100);
1156		}
1157	} else {
1158		/* NUD_PROBE|NUD_INCOMPLETE */
1159		next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME), HZ/100);
1160	}
1161
1162	if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
1163	    atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
1164		neigh->nud_state = NUD_FAILED;
1165		notify = 1;
1166		neigh_invalidate(neigh);
1167		goto out;
1168	}
1169
1170	if (neigh->nud_state & NUD_IN_TIMER) {
1171		if (time_before(next, jiffies + HZ/100))
1172			next = jiffies + HZ/100;
1173		if (!mod_timer(&neigh->timer, next))
1174			neigh_hold(neigh);
1175	}
1176	if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
1177		neigh_probe(neigh);
1178	} else {
1179out:
1180		write_unlock(&neigh->lock);
1181	}
1182
1183	if (notify)
1184		neigh_update_notify(neigh, 0);
1185
1186	trace_neigh_timer_handler(neigh, 0);
1187
1188	neigh_release(neigh);
1189}
1190
1191int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb,
1192		       const bool immediate_ok)
1193{
1194	int rc;
1195	bool immediate_probe = false;
1196
1197	write_lock_bh(&neigh->lock);
1198
1199	rc = 0;
1200	if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
1201		goto out_unlock_bh;
1202	if (neigh->dead)
1203		goto out_dead;
1204
1205	if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
1206		if (NEIGH_VAR(neigh->parms, MCAST_PROBES) +
1207		    NEIGH_VAR(neigh->parms, APP_PROBES)) {
1208			unsigned long next, now = jiffies;
1209
1210			atomic_set(&neigh->probes,
1211				   NEIGH_VAR(neigh->parms, UCAST_PROBES));
1212			neigh_del_timer(neigh);
1213			neigh->nud_state = NUD_INCOMPLETE;
1214			neigh->updated = now;
1215			if (!immediate_ok) {
1216				next = now + 1;
1217			} else {
1218				immediate_probe = true;
1219				next = now + max(NEIGH_VAR(neigh->parms,
1220							   RETRANS_TIME),
1221						 HZ / 100);
1222			}
1223			neigh_add_timer(neigh, next);
 
1224		} else {
1225			neigh->nud_state = NUD_FAILED;
1226			neigh->updated = jiffies;
1227			write_unlock_bh(&neigh->lock);
1228
1229			kfree_skb_reason(skb, SKB_DROP_REASON_NEIGH_FAILED);
1230			return 1;
1231		}
1232	} else if (neigh->nud_state & NUD_STALE) {
1233		neigh_dbg(2, "neigh %p is delayed\n", neigh);
1234		neigh_del_timer(neigh);
1235		neigh->nud_state = NUD_DELAY;
1236		neigh->updated = jiffies;
1237		neigh_add_timer(neigh, jiffies +
1238				NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME));
1239	}
1240
1241	if (neigh->nud_state == NUD_INCOMPLETE) {
1242		if (skb) {
1243			while (neigh->arp_queue_len_bytes + skb->truesize >
1244			       NEIGH_VAR(neigh->parms, QUEUE_LEN_BYTES)) {
1245				struct sk_buff *buff;
1246
1247				buff = __skb_dequeue(&neigh->arp_queue);
1248				if (!buff)
1249					break;
1250				neigh->arp_queue_len_bytes -= buff->truesize;
1251				kfree_skb_reason(buff, SKB_DROP_REASON_NEIGH_QUEUEFULL);
1252				NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
1253			}
1254			skb_dst_force(skb);
1255			__skb_queue_tail(&neigh->arp_queue, skb);
1256			neigh->arp_queue_len_bytes += skb->truesize;
1257		}
1258		rc = 1;
1259	}
1260out_unlock_bh:
1261	if (immediate_probe)
1262		neigh_probe(neigh);
1263	else
1264		write_unlock(&neigh->lock);
1265	local_bh_enable();
1266	trace_neigh_event_send_done(neigh, rc);
1267	return rc;
1268
1269out_dead:
1270	if (neigh->nud_state & NUD_STALE)
1271		goto out_unlock_bh;
1272	write_unlock_bh(&neigh->lock);
1273	kfree_skb_reason(skb, SKB_DROP_REASON_NEIGH_DEAD);
1274	trace_neigh_event_send_dead(neigh, 1);
1275	return 1;
1276}
1277EXPORT_SYMBOL(__neigh_event_send);
1278
1279static void neigh_update_hhs(struct neighbour *neigh)
1280{
1281	struct hh_cache *hh;
1282	void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
1283		= NULL;
1284
1285	if (neigh->dev->header_ops)
1286		update = neigh->dev->header_ops->cache_update;
1287
1288	if (update) {
1289		hh = &neigh->hh;
1290		if (READ_ONCE(hh->hh_len)) {
1291			write_seqlock_bh(&hh->hh_lock);
1292			update(hh, neigh->dev, neigh->ha);
1293			write_sequnlock_bh(&hh->hh_lock);
1294		}
1295	}
1296}
1297
 
 
1298/* Generic update routine.
1299   -- lladdr is new lladdr or NULL, if it is not supplied.
1300   -- new    is new state.
1301   -- flags
1302	NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
1303				if it is different.
1304	NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
1305				lladdr instead of overriding it
1306				if it is different.
 
 
1307	NEIGH_UPDATE_F_ADMIN	means that the change is administrative.
1308	NEIGH_UPDATE_F_USE	means that the entry is user triggered.
1309	NEIGH_UPDATE_F_MANAGED	means that the entry will be auto-refreshed.
1310	NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
1311				NTF_ROUTER flag.
1312	NEIGH_UPDATE_F_ISROUTER	indicates if the neighbour is known as
1313				a router.
1314
1315   Caller MUST hold reference count on the entry.
1316 */
1317static int __neigh_update(struct neighbour *neigh, const u8 *lladdr,
1318			  u8 new, u32 flags, u32 nlmsg_pid,
1319			  struct netlink_ext_ack *extack)
1320{
1321	bool gc_update = false, managed_update = false;
 
 
 
1322	int update_isrouter = 0;
1323	struct net_device *dev;
1324	int err, notify = 0;
1325	u8 old;
1326
1327	trace_neigh_update(neigh, lladdr, new, flags, nlmsg_pid);
1328
1329	write_lock_bh(&neigh->lock);
1330
1331	dev    = neigh->dev;
1332	old    = neigh->nud_state;
1333	err    = -EPERM;
1334
1335	if (neigh->dead) {
1336		NL_SET_ERR_MSG(extack, "Neighbor entry is now dead");
1337		new = old;
1338		goto out;
1339	}
1340	if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
1341	    (old & (NUD_NOARP | NUD_PERMANENT)))
1342		goto out;
1343
1344	neigh_update_flags(neigh, flags, &notify, &gc_update, &managed_update);
1345	if (flags & (NEIGH_UPDATE_F_USE | NEIGH_UPDATE_F_MANAGED)) {
1346		new = old & ~NUD_PERMANENT;
1347		neigh->nud_state = new;
1348		err = 0;
1349		goto out;
1350	}
1351
1352	if (!(new & NUD_VALID)) {
1353		neigh_del_timer(neigh);
1354		if (old & NUD_CONNECTED)
1355			neigh_suspect(neigh);
1356		neigh->nud_state = new;
1357		err = 0;
1358		notify = old & NUD_VALID;
1359		if ((old & (NUD_INCOMPLETE | NUD_PROBE)) &&
1360		    (new & NUD_FAILED)) {
1361			neigh_invalidate(neigh);
1362			notify = 1;
1363		}
1364		goto out;
1365	}
1366
1367	/* Compare new lladdr with cached one */
1368	if (!dev->addr_len) {
1369		/* First case: device needs no address. */
1370		lladdr = neigh->ha;
1371	} else if (lladdr) {
1372		/* The second case: if something is already cached
1373		   and a new address is proposed:
1374		   - compare new & old
1375		   - if they are different, check override flag
1376		 */
1377		if ((old & NUD_VALID) &&
1378		    !memcmp(lladdr, neigh->ha, dev->addr_len))
1379			lladdr = neigh->ha;
1380	} else {
1381		/* No address is supplied; if we know something,
1382		   use it, otherwise discard the request.
1383		 */
1384		err = -EINVAL;
1385		if (!(old & NUD_VALID)) {
1386			NL_SET_ERR_MSG(extack, "No link layer address given");
1387			goto out;
1388		}
1389		lladdr = neigh->ha;
1390	}
1391
1392	/* Update confirmed timestamp for neighbour entry after we
1393	 * received ARP packet even if it doesn't change IP to MAC binding.
1394	 */
1395	if (new & NUD_CONNECTED)
1396		neigh->confirmed = jiffies;
 
1397
1398	/* If entry was valid and address is not changed,
1399	   do not change entry state, if new one is STALE.
1400	 */
1401	err = 0;
1402	update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1403	if (old & NUD_VALID) {
1404		if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
1405			update_isrouter = 0;
1406			if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
1407			    (old & NUD_CONNECTED)) {
1408				lladdr = neigh->ha;
1409				new = NUD_STALE;
1410			} else
1411				goto out;
1412		} else {
1413			if (lladdr == neigh->ha && new == NUD_STALE &&
1414			    !(flags & NEIGH_UPDATE_F_ADMIN))
 
 
1415				new = old;
1416		}
1417	}
1418
1419	/* Update timestamp only once we know we will make a change to the
1420	 * neighbour entry. Otherwise we risk to move the locktime window with
1421	 * noop updates and ignore relevant ARP updates.
1422	 */
1423	if (new != old || lladdr != neigh->ha)
1424		neigh->updated = jiffies;
1425
1426	if (new != old) {
1427		neigh_del_timer(neigh);
1428		if (new & NUD_PROBE)
1429			atomic_set(&neigh->probes, 0);
1430		if (new & NUD_IN_TIMER)
1431			neigh_add_timer(neigh, (jiffies +
1432						((new & NUD_REACHABLE) ?
1433						 neigh->parms->reachable_time :
1434						 0)));
1435		neigh->nud_state = new;
1436		notify = 1;
1437	}
1438
1439	if (lladdr != neigh->ha) {
1440		write_seqlock(&neigh->ha_lock);
1441		memcpy(&neigh->ha, lladdr, dev->addr_len);
1442		write_sequnlock(&neigh->ha_lock);
1443		neigh_update_hhs(neigh);
1444		if (!(new & NUD_CONNECTED))
1445			neigh->confirmed = jiffies -
1446				      (NEIGH_VAR(neigh->parms, BASE_REACHABLE_TIME) << 1);
1447		notify = 1;
1448	}
1449	if (new == old)
1450		goto out;
1451	if (new & NUD_CONNECTED)
1452		neigh_connect(neigh);
1453	else
1454		neigh_suspect(neigh);
1455	if (!(old & NUD_VALID)) {
1456		struct sk_buff *skb;
1457
1458		/* Again: avoid dead loop if something went wrong */
1459
1460		while (neigh->nud_state & NUD_VALID &&
1461		       (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1462			struct dst_entry *dst = skb_dst(skb);
1463			struct neighbour *n2, *n1 = neigh;
1464			write_unlock_bh(&neigh->lock);
1465
1466			rcu_read_lock();
1467
1468			/* Why not just use 'neigh' as-is?  The problem is that
1469			 * things such as shaper, eql, and sch_teql can end up
1470			 * using alternative, different, neigh objects to output
1471			 * the packet in the output path.  So what we need to do
1472			 * here is re-lookup the top-level neigh in the path so
1473			 * we can reinject the packet there.
1474			 */
1475			n2 = NULL;
1476			if (dst && dst->obsolete != DST_OBSOLETE_DEAD) {
1477				n2 = dst_neigh_lookup_skb(dst, skb);
1478				if (n2)
1479					n1 = n2;
1480			}
1481			n1->output(n1, skb);
1482			if (n2)
1483				neigh_release(n2);
1484			rcu_read_unlock();
1485
1486			write_lock_bh(&neigh->lock);
1487		}
1488		__skb_queue_purge(&neigh->arp_queue);
1489		neigh->arp_queue_len_bytes = 0;
1490	}
1491out:
1492	if (update_isrouter)
1493		neigh_update_is_router(neigh, flags, &notify);
 
 
 
1494	write_unlock_bh(&neigh->lock);
1495	if (((new ^ old) & NUD_PERMANENT) || gc_update)
1496		neigh_update_gc_list(neigh);
1497	if (managed_update)
1498		neigh_update_managed_list(neigh);
1499	if (notify)
1500		neigh_update_notify(neigh, nlmsg_pid);
1501	trace_neigh_update_done(neigh, err);
1502	return err;
1503}
1504
1505int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
1506		 u32 flags, u32 nlmsg_pid)
1507{
1508	return __neigh_update(neigh, lladdr, new, flags, nlmsg_pid, NULL);
1509}
1510EXPORT_SYMBOL(neigh_update);
1511
1512/* Update the neigh to listen temporarily for probe responses, even if it is
1513 * in a NUD_FAILED state. The caller has to hold neigh->lock for writing.
1514 */
1515void __neigh_set_probe_once(struct neighbour *neigh)
1516{
1517	if (neigh->dead)
1518		return;
1519	neigh->updated = jiffies;
1520	if (!(neigh->nud_state & NUD_FAILED))
1521		return;
1522	neigh->nud_state = NUD_INCOMPLETE;
1523	atomic_set(&neigh->probes, neigh_max_probes(neigh));
1524	neigh_add_timer(neigh,
1525			jiffies + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
1526				      HZ/100));
1527}
1528EXPORT_SYMBOL(__neigh_set_probe_once);
1529
1530struct neighbour *neigh_event_ns(struct neigh_table *tbl,
1531				 u8 *lladdr, void *saddr,
1532				 struct net_device *dev)
1533{
1534	struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev,
1535						 lladdr || !dev->addr_len);
1536	if (neigh)
1537		neigh_update(neigh, lladdr, NUD_STALE,
1538			     NEIGH_UPDATE_F_OVERRIDE, 0);
1539	return neigh;
1540}
1541EXPORT_SYMBOL(neigh_event_ns);
1542
1543/* called with read_lock_bh(&n->lock); */
1544static void neigh_hh_init(struct neighbour *n)
1545{
1546	struct net_device *dev = n->dev;
1547	__be16 prot = n->tbl->protocol;
1548	struct hh_cache	*hh = &n->hh;
1549
1550	write_lock_bh(&n->lock);
1551
1552	/* Only one thread can come in here and initialize the
1553	 * hh_cache entry.
1554	 */
1555	if (!hh->hh_len)
1556		dev->header_ops->cache(n, hh, prot);
1557
1558	write_unlock_bh(&n->lock);
1559}
1560
1561/* Slow and careful. */
1562
1563int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb)
1564{
1565	int rc = 0;
1566
1567	if (!neigh_event_send(neigh, skb)) {
1568		int err;
1569		struct net_device *dev = neigh->dev;
1570		unsigned int seq;
1571
1572		if (dev->header_ops->cache && !READ_ONCE(neigh->hh.hh_len))
1573			neigh_hh_init(neigh);
1574
1575		do {
1576			__skb_pull(skb, skb_network_offset(skb));
1577			seq = read_seqbegin(&neigh->ha_lock);
1578			err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1579					      neigh->ha, NULL, skb->len);
1580		} while (read_seqretry(&neigh->ha_lock, seq));
1581
1582		if (err >= 0)
1583			rc = dev_queue_xmit(skb);
1584		else
1585			goto out_kfree_skb;
1586	}
1587out:
1588	return rc;
1589out_kfree_skb:
1590	rc = -EINVAL;
1591	kfree_skb(skb);
1592	goto out;
1593}
1594EXPORT_SYMBOL(neigh_resolve_output);
1595
1596/* As fast as possible without hh cache */
1597
1598int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb)
1599{
1600	struct net_device *dev = neigh->dev;
1601	unsigned int seq;
1602	int err;
1603
1604	do {
1605		__skb_pull(skb, skb_network_offset(skb));
1606		seq = read_seqbegin(&neigh->ha_lock);
1607		err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1608				      neigh->ha, NULL, skb->len);
1609	} while (read_seqretry(&neigh->ha_lock, seq));
1610
1611	if (err >= 0)
1612		err = dev_queue_xmit(skb);
1613	else {
1614		err = -EINVAL;
1615		kfree_skb(skb);
1616	}
1617	return err;
1618}
1619EXPORT_SYMBOL(neigh_connected_output);
1620
1621int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb)
1622{
1623	return dev_queue_xmit(skb);
1624}
1625EXPORT_SYMBOL(neigh_direct_output);
1626
1627static void neigh_managed_work(struct work_struct *work)
1628{
1629	struct neigh_table *tbl = container_of(work, struct neigh_table,
1630					       managed_work.work);
1631	struct neighbour *neigh;
1632
1633	write_lock_bh(&tbl->lock);
1634	list_for_each_entry(neigh, &tbl->managed_list, managed_list)
1635		neigh_event_send_probe(neigh, NULL, false);
1636	queue_delayed_work(system_power_efficient_wq, &tbl->managed_work,
1637			   NEIGH_VAR(&tbl->parms, INTERVAL_PROBE_TIME_MS));
1638	write_unlock_bh(&tbl->lock);
1639}
1640
1641static void neigh_proxy_process(struct timer_list *t)
1642{
1643	struct neigh_table *tbl = from_timer(tbl, t, proxy_timer);
1644	long sched_next = 0;
1645	unsigned long now = jiffies;
1646	struct sk_buff *skb, *n;
1647
1648	spin_lock(&tbl->proxy_queue.lock);
1649
1650	skb_queue_walk_safe(&tbl->proxy_queue, skb, n) {
1651		long tdif = NEIGH_CB(skb)->sched_next - now;
1652
1653		if (tdif <= 0) {
1654			struct net_device *dev = skb->dev;
1655
1656			neigh_parms_qlen_dec(dev, tbl->family);
1657			__skb_unlink(skb, &tbl->proxy_queue);
1658
1659			if (tbl->proxy_redo && netif_running(dev)) {
1660				rcu_read_lock();
1661				tbl->proxy_redo(skb);
1662				rcu_read_unlock();
1663			} else {
1664				kfree_skb(skb);
1665			}
1666
1667			dev_put(dev);
1668		} else if (!sched_next || tdif < sched_next)
1669			sched_next = tdif;
1670	}
1671	del_timer(&tbl->proxy_timer);
1672	if (sched_next)
1673		mod_timer(&tbl->proxy_timer, jiffies + sched_next);
1674	spin_unlock(&tbl->proxy_queue.lock);
1675}
1676
1677void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
1678		    struct sk_buff *skb)
1679{
1680	unsigned long sched_next = jiffies +
1681			get_random_u32_below(NEIGH_VAR(p, PROXY_DELAY));
 
 
1682
1683	if (p->qlen > NEIGH_VAR(p, PROXY_QLEN)) {
1684		kfree_skb(skb);
1685		return;
1686	}
1687
1688	NEIGH_CB(skb)->sched_next = sched_next;
1689	NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
1690
1691	spin_lock(&tbl->proxy_queue.lock);
1692	if (del_timer(&tbl->proxy_timer)) {
1693		if (time_before(tbl->proxy_timer.expires, sched_next))
1694			sched_next = tbl->proxy_timer.expires;
1695	}
1696	skb_dst_drop(skb);
1697	dev_hold(skb->dev);
1698	__skb_queue_tail(&tbl->proxy_queue, skb);
1699	p->qlen++;
1700	mod_timer(&tbl->proxy_timer, sched_next);
1701	spin_unlock(&tbl->proxy_queue.lock);
1702}
1703EXPORT_SYMBOL(pneigh_enqueue);
1704
1705static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl,
1706						      struct net *net, int ifindex)
1707{
1708	struct neigh_parms *p;
1709
1710	list_for_each_entry(p, &tbl->parms_list, list) {
1711		if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
1712		    (!p->dev && !ifindex && net_eq(net, &init_net)))
1713			return p;
1714	}
1715
1716	return NULL;
1717}
1718
1719struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
1720				      struct neigh_table *tbl)
1721{
1722	struct neigh_parms *p;
1723	struct net *net = dev_net(dev);
1724	const struct net_device_ops *ops = dev->netdev_ops;
1725
1726	p = kmemdup(&tbl->parms, sizeof(*p), GFP_KERNEL);
1727	if (p) {
1728		p->tbl		  = tbl;
1729		refcount_set(&p->refcnt, 1);
1730		p->reachable_time =
1731				neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
1732		p->qlen = 0;
1733		netdev_hold(dev, &p->dev_tracker, GFP_KERNEL);
1734		p->dev = dev;
1735		write_pnet(&p->net, net);
1736		p->sysctl_table = NULL;
1737
1738		if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) {
1739			netdev_put(dev, &p->dev_tracker);
1740			kfree(p);
1741			return NULL;
1742		}
1743
1744		write_lock_bh(&tbl->lock);
1745		list_add(&p->list, &tbl->parms.list);
1746		write_unlock_bh(&tbl->lock);
1747
1748		neigh_parms_data_state_cleanall(p);
1749	}
1750	return p;
1751}
1752EXPORT_SYMBOL(neigh_parms_alloc);
1753
1754static void neigh_rcu_free_parms(struct rcu_head *head)
1755{
1756	struct neigh_parms *parms =
1757		container_of(head, struct neigh_parms, rcu_head);
1758
1759	neigh_parms_put(parms);
1760}
1761
1762void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
1763{
1764	if (!parms || parms == &tbl->parms)
1765		return;
1766	write_lock_bh(&tbl->lock);
1767	list_del(&parms->list);
1768	parms->dead = 1;
1769	write_unlock_bh(&tbl->lock);
1770	netdev_put(parms->dev, &parms->dev_tracker);
 
1771	call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
1772}
1773EXPORT_SYMBOL(neigh_parms_release);
1774
1775static void neigh_parms_destroy(struct neigh_parms *parms)
1776{
1777	kfree(parms);
1778}
1779
1780static struct lock_class_key neigh_table_proxy_queue_class;
1781
1782static struct neigh_table *neigh_tables[NEIGH_NR_TABLES] __read_mostly;
1783
1784void neigh_table_init(int index, struct neigh_table *tbl)
1785{
1786	unsigned long now = jiffies;
1787	unsigned long phsize;
1788
1789	INIT_LIST_HEAD(&tbl->parms_list);
1790	INIT_LIST_HEAD(&tbl->gc_list);
1791	INIT_LIST_HEAD(&tbl->managed_list);
1792
1793	list_add(&tbl->parms.list, &tbl->parms_list);
1794	write_pnet(&tbl->parms.net, &init_net);
1795	refcount_set(&tbl->parms.refcnt, 1);
1796	tbl->parms.reachable_time =
1797			  neigh_rand_reach_time(NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME));
1798	tbl->parms.qlen = 0;
1799
1800	tbl->stats = alloc_percpu(struct neigh_statistics);
1801	if (!tbl->stats)
1802		panic("cannot create neighbour cache statistics");
1803
1804#ifdef CONFIG_PROC_FS
1805	if (!proc_create_seq_data(tbl->id, 0, init_net.proc_net_stat,
1806			      &neigh_stat_seq_ops, tbl))
1807		panic("cannot create neighbour proc dir entry");
1808#endif
1809
1810	RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3));
1811
1812	phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
1813	tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
1814
1815	if (!tbl->nht || !tbl->phash_buckets)
1816		panic("cannot allocate neighbour cache hashes");
1817
1818	if (!tbl->entry_size)
1819		tbl->entry_size = ALIGN(offsetof(struct neighbour, primary_key) +
1820					tbl->key_len, NEIGH_PRIV_ALIGN);
1821	else
1822		WARN_ON(tbl->entry_size % NEIGH_PRIV_ALIGN);
1823
1824	rwlock_init(&tbl->lock);
1825
1826	INIT_DEFERRABLE_WORK(&tbl->gc_work, neigh_periodic_work);
1827	queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
1828			tbl->parms.reachable_time);
1829	INIT_DEFERRABLE_WORK(&tbl->managed_work, neigh_managed_work);
1830	queue_delayed_work(system_power_efficient_wq, &tbl->managed_work, 0);
1831
1832	timer_setup(&tbl->proxy_timer, neigh_proxy_process, 0);
1833	skb_queue_head_init_class(&tbl->proxy_queue,
1834			&neigh_table_proxy_queue_class);
1835
1836	tbl->last_flush = now;
1837	tbl->last_rand	= now + tbl->parms.reachable_time * 20;
1838
1839	neigh_tables[index] = tbl;
1840}
1841EXPORT_SYMBOL(neigh_table_init);
1842
1843int neigh_table_clear(int index, struct neigh_table *tbl)
1844{
1845	neigh_tables[index] = NULL;
1846	/* It is not clean... Fix it to unload IPv6 module safely */
1847	cancel_delayed_work_sync(&tbl->managed_work);
1848	cancel_delayed_work_sync(&tbl->gc_work);
1849	del_timer_sync(&tbl->proxy_timer);
1850	pneigh_queue_purge(&tbl->proxy_queue, NULL, tbl->family);
1851	neigh_ifdown(tbl, NULL);
1852	if (atomic_read(&tbl->entries))
1853		pr_crit("neighbour leakage\n");
1854
1855	call_rcu(&rcu_dereference_protected(tbl->nht, 1)->rcu,
1856		 neigh_hash_free_rcu);
1857	tbl->nht = NULL;
1858
1859	kfree(tbl->phash_buckets);
1860	tbl->phash_buckets = NULL;
1861
1862	remove_proc_entry(tbl->id, init_net.proc_net_stat);
1863
1864	free_percpu(tbl->stats);
1865	tbl->stats = NULL;
1866
1867	return 0;
1868}
1869EXPORT_SYMBOL(neigh_table_clear);
1870
1871static struct neigh_table *neigh_find_table(int family)
1872{
1873	struct neigh_table *tbl = NULL;
1874
1875	switch (family) {
1876	case AF_INET:
1877		tbl = neigh_tables[NEIGH_ARP_TABLE];
1878		break;
1879	case AF_INET6:
1880		tbl = neigh_tables[NEIGH_ND_TABLE];
1881		break;
 
 
 
1882	}
1883
1884	return tbl;
1885}
1886
1887const struct nla_policy nda_policy[NDA_MAX+1] = {
1888	[NDA_UNSPEC]		= { .strict_start_type = NDA_NH_ID },
1889	[NDA_DST]		= { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
1890	[NDA_LLADDR]		= { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
1891	[NDA_CACHEINFO]		= { .len = sizeof(struct nda_cacheinfo) },
1892	[NDA_PROBES]		= { .type = NLA_U32 },
1893	[NDA_VLAN]		= { .type = NLA_U16 },
1894	[NDA_PORT]		= { .type = NLA_U16 },
1895	[NDA_VNI]		= { .type = NLA_U32 },
1896	[NDA_IFINDEX]		= { .type = NLA_U32 },
1897	[NDA_MASTER]		= { .type = NLA_U32 },
1898	[NDA_PROTOCOL]		= { .type = NLA_U8 },
1899	[NDA_NH_ID]		= { .type = NLA_U32 },
1900	[NDA_FLAGS_EXT]		= NLA_POLICY_MASK(NLA_U32, NTF_EXT_MASK),
1901	[NDA_FDB_EXT_ATTRS]	= { .type = NLA_NESTED },
1902};
1903
1904static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh,
1905			struct netlink_ext_ack *extack)
1906{
1907	struct net *net = sock_net(skb->sk);
1908	struct ndmsg *ndm;
1909	struct nlattr *dst_attr;
1910	struct neigh_table *tbl;
1911	struct neighbour *neigh;
1912	struct net_device *dev = NULL;
1913	int err = -EINVAL;
1914
1915	ASSERT_RTNL();
1916	if (nlmsg_len(nlh) < sizeof(*ndm))
1917		goto out;
1918
1919	dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
1920	if (!dst_attr) {
1921		NL_SET_ERR_MSG(extack, "Network address not specified");
1922		goto out;
1923	}
1924
1925	ndm = nlmsg_data(nlh);
1926	if (ndm->ndm_ifindex) {
1927		dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1928		if (dev == NULL) {
1929			err = -ENODEV;
1930			goto out;
1931		}
1932	}
1933
1934	tbl = neigh_find_table(ndm->ndm_family);
1935	if (tbl == NULL)
1936		return -EAFNOSUPPORT;
1937
1938	if (nla_len(dst_attr) < (int)tbl->key_len) {
1939		NL_SET_ERR_MSG(extack, "Invalid network address");
1940		goto out;
1941	}
1942
1943	if (ndm->ndm_flags & NTF_PROXY) {
1944		err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
1945		goto out;
1946	}
1947
1948	if (dev == NULL)
1949		goto out;
1950
1951	neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
1952	if (neigh == NULL) {
1953		err = -ENOENT;
1954		goto out;
1955	}
1956
1957	err = __neigh_update(neigh, NULL, NUD_FAILED,
1958			     NEIGH_UPDATE_F_OVERRIDE | NEIGH_UPDATE_F_ADMIN,
1959			     NETLINK_CB(skb).portid, extack);
1960	write_lock_bh(&tbl->lock);
1961	neigh_release(neigh);
1962	neigh_remove_one(neigh, tbl);
1963	write_unlock_bh(&tbl->lock);
1964
1965out:
1966	return err;
1967}
1968
1969static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh,
1970		     struct netlink_ext_ack *extack)
1971{
1972	int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE |
1973		    NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1974	struct net *net = sock_net(skb->sk);
1975	struct ndmsg *ndm;
1976	struct nlattr *tb[NDA_MAX+1];
1977	struct neigh_table *tbl;
1978	struct net_device *dev = NULL;
1979	struct neighbour *neigh;
1980	void *dst, *lladdr;
1981	u8 protocol = 0;
1982	u32 ndm_flags;
1983	int err;
1984
1985	ASSERT_RTNL();
1986	err = nlmsg_parse_deprecated(nlh, sizeof(*ndm), tb, NDA_MAX,
1987				     nda_policy, extack);
1988	if (err < 0)
1989		goto out;
1990
1991	err = -EINVAL;
1992	if (!tb[NDA_DST]) {
1993		NL_SET_ERR_MSG(extack, "Network address not specified");
1994		goto out;
1995	}
1996
1997	ndm = nlmsg_data(nlh);
1998	ndm_flags = ndm->ndm_flags;
1999	if (tb[NDA_FLAGS_EXT]) {
2000		u32 ext = nla_get_u32(tb[NDA_FLAGS_EXT]);
2001
2002		BUILD_BUG_ON(sizeof(neigh->flags) * BITS_PER_BYTE <
2003			     (sizeof(ndm->ndm_flags) * BITS_PER_BYTE +
2004			      hweight32(NTF_EXT_MASK)));
2005		ndm_flags |= (ext << NTF_EXT_SHIFT);
2006	}
2007	if (ndm->ndm_ifindex) {
2008		dev = __dev_get_by_index(net, ndm->ndm_ifindex);
2009		if (dev == NULL) {
2010			err = -ENODEV;
2011			goto out;
2012		}
2013
2014		if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len) {
2015			NL_SET_ERR_MSG(extack, "Invalid link address");
2016			goto out;
2017		}
2018	}
2019
2020	tbl = neigh_find_table(ndm->ndm_family);
2021	if (tbl == NULL)
2022		return -EAFNOSUPPORT;
2023
2024	if (nla_len(tb[NDA_DST]) < (int)tbl->key_len) {
2025		NL_SET_ERR_MSG(extack, "Invalid network address");
2026		goto out;
2027	}
2028
2029	dst = nla_data(tb[NDA_DST]);
2030	lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
2031
2032	if (tb[NDA_PROTOCOL])
2033		protocol = nla_get_u8(tb[NDA_PROTOCOL]);
2034	if (ndm_flags & NTF_PROXY) {
2035		struct pneigh_entry *pn;
2036
2037		if (ndm_flags & NTF_MANAGED) {
2038			NL_SET_ERR_MSG(extack, "Invalid NTF_* flag combination");
2039			goto out;
2040		}
2041
2042		err = -ENOBUFS;
2043		pn = pneigh_lookup(tbl, net, dst, dev, 1);
2044		if (pn) {
2045			pn->flags = ndm_flags;
2046			if (protocol)
2047				pn->protocol = protocol;
2048			err = 0;
2049		}
2050		goto out;
2051	}
2052
2053	if (!dev) {
2054		NL_SET_ERR_MSG(extack, "Device not specified");
2055		goto out;
2056	}
2057
2058	if (tbl->allow_add && !tbl->allow_add(dev, extack)) {
2059		err = -EINVAL;
2060		goto out;
2061	}
2062
2063	neigh = neigh_lookup(tbl, dst, dev);
2064	if (neigh == NULL) {
2065		bool ndm_permanent  = ndm->ndm_state & NUD_PERMANENT;
2066		bool exempt_from_gc = ndm_permanent ||
2067				      ndm_flags & NTF_EXT_LEARNED;
2068
2069		if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
2070			err = -ENOENT;
2071			goto out;
2072		}
2073		if (ndm_permanent && (ndm_flags & NTF_MANAGED)) {
2074			NL_SET_ERR_MSG(extack, "Invalid NTF_* flag for permanent entry");
2075			err = -EINVAL;
2076			goto out;
2077		}
2078
2079		neigh = ___neigh_create(tbl, dst, dev,
2080					ndm_flags &
2081					(NTF_EXT_LEARNED | NTF_MANAGED),
2082					exempt_from_gc, true);
2083		if (IS_ERR(neigh)) {
2084			err = PTR_ERR(neigh);
2085			goto out;
2086		}
2087	} else {
2088		if (nlh->nlmsg_flags & NLM_F_EXCL) {
2089			err = -EEXIST;
2090			neigh_release(neigh);
2091			goto out;
2092		}
2093
2094		if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
2095			flags &= ~(NEIGH_UPDATE_F_OVERRIDE |
2096				   NEIGH_UPDATE_F_OVERRIDE_ISROUTER);
2097	}
2098
2099	if (protocol)
2100		neigh->protocol = protocol;
2101	if (ndm_flags & NTF_EXT_LEARNED)
2102		flags |= NEIGH_UPDATE_F_EXT_LEARNED;
2103	if (ndm_flags & NTF_ROUTER)
2104		flags |= NEIGH_UPDATE_F_ISROUTER;
2105	if (ndm_flags & NTF_MANAGED)
2106		flags |= NEIGH_UPDATE_F_MANAGED;
2107	if (ndm_flags & NTF_USE)
2108		flags |= NEIGH_UPDATE_F_USE;
2109
2110	err = __neigh_update(neigh, lladdr, ndm->ndm_state, flags,
2111			     NETLINK_CB(skb).portid, extack);
2112	if (!err && ndm_flags & (NTF_USE | NTF_MANAGED)) {
2113		neigh_event_send(neigh, NULL);
2114		err = 0;
2115	}
 
2116	neigh_release(neigh);
 
2117out:
2118	return err;
2119}
2120
2121static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
2122{
2123	struct nlattr *nest;
2124
2125	nest = nla_nest_start_noflag(skb, NDTA_PARMS);
2126	if (nest == NULL)
2127		return -ENOBUFS;
2128
2129	if ((parms->dev &&
2130	     nla_put_u32(skb, NDTPA_IFINDEX, parms->dev->ifindex)) ||
2131	    nla_put_u32(skb, NDTPA_REFCNT, refcount_read(&parms->refcnt)) ||
2132	    nla_put_u32(skb, NDTPA_QUEUE_LENBYTES,
2133			NEIGH_VAR(parms, QUEUE_LEN_BYTES)) ||
2134	    /* approximative value for deprecated QUEUE_LEN (in packets) */
2135	    nla_put_u32(skb, NDTPA_QUEUE_LEN,
2136			NEIGH_VAR(parms, QUEUE_LEN_BYTES) / SKB_TRUESIZE(ETH_FRAME_LEN)) ||
2137	    nla_put_u32(skb, NDTPA_PROXY_QLEN, NEIGH_VAR(parms, PROXY_QLEN)) ||
2138	    nla_put_u32(skb, NDTPA_APP_PROBES, NEIGH_VAR(parms, APP_PROBES)) ||
2139	    nla_put_u32(skb, NDTPA_UCAST_PROBES,
2140			NEIGH_VAR(parms, UCAST_PROBES)) ||
2141	    nla_put_u32(skb, NDTPA_MCAST_PROBES,
2142			NEIGH_VAR(parms, MCAST_PROBES)) ||
2143	    nla_put_u32(skb, NDTPA_MCAST_REPROBES,
2144			NEIGH_VAR(parms, MCAST_REPROBES)) ||
2145	    nla_put_msecs(skb, NDTPA_REACHABLE_TIME, parms->reachable_time,
2146			  NDTPA_PAD) ||
2147	    nla_put_msecs(skb, NDTPA_BASE_REACHABLE_TIME,
2148			  NEIGH_VAR(parms, BASE_REACHABLE_TIME), NDTPA_PAD) ||
2149	    nla_put_msecs(skb, NDTPA_GC_STALETIME,
2150			  NEIGH_VAR(parms, GC_STALETIME), NDTPA_PAD) ||
2151	    nla_put_msecs(skb, NDTPA_DELAY_PROBE_TIME,
2152			  NEIGH_VAR(parms, DELAY_PROBE_TIME), NDTPA_PAD) ||
2153	    nla_put_msecs(skb, NDTPA_RETRANS_TIME,
2154			  NEIGH_VAR(parms, RETRANS_TIME), NDTPA_PAD) ||
2155	    nla_put_msecs(skb, NDTPA_ANYCAST_DELAY,
2156			  NEIGH_VAR(parms, ANYCAST_DELAY), NDTPA_PAD) ||
2157	    nla_put_msecs(skb, NDTPA_PROXY_DELAY,
2158			  NEIGH_VAR(parms, PROXY_DELAY), NDTPA_PAD) ||
2159	    nla_put_msecs(skb, NDTPA_LOCKTIME,
2160			  NEIGH_VAR(parms, LOCKTIME), NDTPA_PAD) ||
2161	    nla_put_msecs(skb, NDTPA_INTERVAL_PROBE_TIME_MS,
2162			  NEIGH_VAR(parms, INTERVAL_PROBE_TIME_MS), NDTPA_PAD))
2163		goto nla_put_failure;
2164	return nla_nest_end(skb, nest);
2165
2166nla_put_failure:
2167	nla_nest_cancel(skb, nest);
2168	return -EMSGSIZE;
2169}
2170
2171static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
2172			      u32 pid, u32 seq, int type, int flags)
2173{
2174	struct nlmsghdr *nlh;
2175	struct ndtmsg *ndtmsg;
2176
2177	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
2178	if (nlh == NULL)
2179		return -EMSGSIZE;
2180
2181	ndtmsg = nlmsg_data(nlh);
2182
2183	read_lock_bh(&tbl->lock);
2184	ndtmsg->ndtm_family = tbl->family;
2185	ndtmsg->ndtm_pad1   = 0;
2186	ndtmsg->ndtm_pad2   = 0;
2187
2188	if (nla_put_string(skb, NDTA_NAME, tbl->id) ||
2189	    nla_put_msecs(skb, NDTA_GC_INTERVAL, tbl->gc_interval, NDTA_PAD) ||
2190	    nla_put_u32(skb, NDTA_THRESH1, tbl->gc_thresh1) ||
2191	    nla_put_u32(skb, NDTA_THRESH2, tbl->gc_thresh2) ||
2192	    nla_put_u32(skb, NDTA_THRESH3, tbl->gc_thresh3))
2193		goto nla_put_failure;
2194	{
2195		unsigned long now = jiffies;
2196		long flush_delta = now - tbl->last_flush;
2197		long rand_delta = now - tbl->last_rand;
2198		struct neigh_hash_table *nht;
2199		struct ndt_config ndc = {
2200			.ndtc_key_len		= tbl->key_len,
2201			.ndtc_entry_size	= tbl->entry_size,
2202			.ndtc_entries		= atomic_read(&tbl->entries),
2203			.ndtc_last_flush	= jiffies_to_msecs(flush_delta),
2204			.ndtc_last_rand		= jiffies_to_msecs(rand_delta),
2205			.ndtc_proxy_qlen	= tbl->proxy_queue.qlen,
2206		};
2207
2208		rcu_read_lock_bh();
2209		nht = rcu_dereference_bh(tbl->nht);
2210		ndc.ndtc_hash_rnd = nht->hash_rnd[0];
2211		ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
2212		rcu_read_unlock_bh();
2213
2214		if (nla_put(skb, NDTA_CONFIG, sizeof(ndc), &ndc))
2215			goto nla_put_failure;
2216	}
2217
2218	{
2219		int cpu;
2220		struct ndt_stats ndst;
2221
2222		memset(&ndst, 0, sizeof(ndst));
2223
2224		for_each_possible_cpu(cpu) {
2225			struct neigh_statistics	*st;
2226
2227			st = per_cpu_ptr(tbl->stats, cpu);
2228			ndst.ndts_allocs		+= st->allocs;
2229			ndst.ndts_destroys		+= st->destroys;
2230			ndst.ndts_hash_grows		+= st->hash_grows;
2231			ndst.ndts_res_failed		+= st->res_failed;
2232			ndst.ndts_lookups		+= st->lookups;
2233			ndst.ndts_hits			+= st->hits;
2234			ndst.ndts_rcv_probes_mcast	+= st->rcv_probes_mcast;
2235			ndst.ndts_rcv_probes_ucast	+= st->rcv_probes_ucast;
2236			ndst.ndts_periodic_gc_runs	+= st->periodic_gc_runs;
2237			ndst.ndts_forced_gc_runs	+= st->forced_gc_runs;
2238			ndst.ndts_table_fulls		+= st->table_fulls;
2239		}
2240
2241		if (nla_put_64bit(skb, NDTA_STATS, sizeof(ndst), &ndst,
2242				  NDTA_PAD))
2243			goto nla_put_failure;
2244	}
2245
2246	BUG_ON(tbl->parms.dev);
2247	if (neightbl_fill_parms(skb, &tbl->parms) < 0)
2248		goto nla_put_failure;
2249
2250	read_unlock_bh(&tbl->lock);
2251	nlmsg_end(skb, nlh);
2252	return 0;
2253
2254nla_put_failure:
2255	read_unlock_bh(&tbl->lock);
2256	nlmsg_cancel(skb, nlh);
2257	return -EMSGSIZE;
2258}
2259
2260static int neightbl_fill_param_info(struct sk_buff *skb,
2261				    struct neigh_table *tbl,
2262				    struct neigh_parms *parms,
2263				    u32 pid, u32 seq, int type,
2264				    unsigned int flags)
2265{
2266	struct ndtmsg *ndtmsg;
2267	struct nlmsghdr *nlh;
2268
2269	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
2270	if (nlh == NULL)
2271		return -EMSGSIZE;
2272
2273	ndtmsg = nlmsg_data(nlh);
2274
2275	read_lock_bh(&tbl->lock);
2276	ndtmsg->ndtm_family = tbl->family;
2277	ndtmsg->ndtm_pad1   = 0;
2278	ndtmsg->ndtm_pad2   = 0;
2279
2280	if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
2281	    neightbl_fill_parms(skb, parms) < 0)
2282		goto errout;
2283
2284	read_unlock_bh(&tbl->lock);
2285	nlmsg_end(skb, nlh);
2286	return 0;
2287errout:
2288	read_unlock_bh(&tbl->lock);
2289	nlmsg_cancel(skb, nlh);
2290	return -EMSGSIZE;
2291}
2292
2293static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
2294	[NDTA_NAME]		= { .type = NLA_STRING },
2295	[NDTA_THRESH1]		= { .type = NLA_U32 },
2296	[NDTA_THRESH2]		= { .type = NLA_U32 },
2297	[NDTA_THRESH3]		= { .type = NLA_U32 },
2298	[NDTA_GC_INTERVAL]	= { .type = NLA_U64 },
2299	[NDTA_PARMS]		= { .type = NLA_NESTED },
2300};
2301
2302static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
2303	[NDTPA_IFINDEX]			= { .type = NLA_U32 },
2304	[NDTPA_QUEUE_LEN]		= { .type = NLA_U32 },
2305	[NDTPA_PROXY_QLEN]		= { .type = NLA_U32 },
2306	[NDTPA_APP_PROBES]		= { .type = NLA_U32 },
2307	[NDTPA_UCAST_PROBES]		= { .type = NLA_U32 },
2308	[NDTPA_MCAST_PROBES]		= { .type = NLA_U32 },
2309	[NDTPA_MCAST_REPROBES]		= { .type = NLA_U32 },
2310	[NDTPA_BASE_REACHABLE_TIME]	= { .type = NLA_U64 },
2311	[NDTPA_GC_STALETIME]		= { .type = NLA_U64 },
2312	[NDTPA_DELAY_PROBE_TIME]	= { .type = NLA_U64 },
2313	[NDTPA_RETRANS_TIME]		= { .type = NLA_U64 },
2314	[NDTPA_ANYCAST_DELAY]		= { .type = NLA_U64 },
2315	[NDTPA_PROXY_DELAY]		= { .type = NLA_U64 },
2316	[NDTPA_LOCKTIME]		= { .type = NLA_U64 },
2317	[NDTPA_INTERVAL_PROBE_TIME_MS]	= { .type = NLA_U64, .min = 1 },
2318};
2319
2320static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh,
2321			struct netlink_ext_ack *extack)
2322{
2323	struct net *net = sock_net(skb->sk);
2324	struct neigh_table *tbl;
2325	struct ndtmsg *ndtmsg;
2326	struct nlattr *tb[NDTA_MAX+1];
2327	bool found = false;
2328	int err, tidx;
2329
2330	err = nlmsg_parse_deprecated(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
2331				     nl_neightbl_policy, extack);
2332	if (err < 0)
2333		goto errout;
2334
2335	if (tb[NDTA_NAME] == NULL) {
2336		err = -EINVAL;
2337		goto errout;
2338	}
2339
2340	ndtmsg = nlmsg_data(nlh);
2341
2342	for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
2343		tbl = neigh_tables[tidx];
2344		if (!tbl)
2345			continue;
2346		if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
2347			continue;
2348		if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0) {
2349			found = true;
2350			break;
2351		}
2352	}
2353
2354	if (!found)
2355		return -ENOENT;
2356
2357	/*
2358	 * We acquire tbl->lock to be nice to the periodic timers and
2359	 * make sure they always see a consistent set of values.
2360	 */
2361	write_lock_bh(&tbl->lock);
2362
2363	if (tb[NDTA_PARMS]) {
2364		struct nlattr *tbp[NDTPA_MAX+1];
2365		struct neigh_parms *p;
2366		int i, ifindex = 0;
2367
2368		err = nla_parse_nested_deprecated(tbp, NDTPA_MAX,
2369						  tb[NDTA_PARMS],
2370						  nl_ntbl_parm_policy, extack);
2371		if (err < 0)
2372			goto errout_tbl_lock;
2373
2374		if (tbp[NDTPA_IFINDEX])
2375			ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
2376
2377		p = lookup_neigh_parms(tbl, net, ifindex);
2378		if (p == NULL) {
2379			err = -ENOENT;
2380			goto errout_tbl_lock;
2381		}
2382
2383		for (i = 1; i <= NDTPA_MAX; i++) {
2384			if (tbp[i] == NULL)
2385				continue;
2386
2387			switch (i) {
2388			case NDTPA_QUEUE_LEN:
2389				NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2390					      nla_get_u32(tbp[i]) *
2391					      SKB_TRUESIZE(ETH_FRAME_LEN));
2392				break;
2393			case NDTPA_QUEUE_LENBYTES:
2394				NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2395					      nla_get_u32(tbp[i]));
2396				break;
2397			case NDTPA_PROXY_QLEN:
2398				NEIGH_VAR_SET(p, PROXY_QLEN,
2399					      nla_get_u32(tbp[i]));
2400				break;
2401			case NDTPA_APP_PROBES:
2402				NEIGH_VAR_SET(p, APP_PROBES,
2403					      nla_get_u32(tbp[i]));
2404				break;
2405			case NDTPA_UCAST_PROBES:
2406				NEIGH_VAR_SET(p, UCAST_PROBES,
2407					      nla_get_u32(tbp[i]));
2408				break;
2409			case NDTPA_MCAST_PROBES:
2410				NEIGH_VAR_SET(p, MCAST_PROBES,
2411					      nla_get_u32(tbp[i]));
2412				break;
2413			case NDTPA_MCAST_REPROBES:
2414				NEIGH_VAR_SET(p, MCAST_REPROBES,
2415					      nla_get_u32(tbp[i]));
2416				break;
2417			case NDTPA_BASE_REACHABLE_TIME:
2418				NEIGH_VAR_SET(p, BASE_REACHABLE_TIME,
2419					      nla_get_msecs(tbp[i]));
2420				/* update reachable_time as well, otherwise, the change will
2421				 * only be effective after the next time neigh_periodic_work
2422				 * decides to recompute it (can be multiple minutes)
2423				 */
2424				p->reachable_time =
2425					neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
2426				break;
2427			case NDTPA_GC_STALETIME:
2428				NEIGH_VAR_SET(p, GC_STALETIME,
2429					      nla_get_msecs(tbp[i]));
2430				break;
2431			case NDTPA_DELAY_PROBE_TIME:
2432				NEIGH_VAR_SET(p, DELAY_PROBE_TIME,
2433					      nla_get_msecs(tbp[i]));
2434				call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
2435				break;
2436			case NDTPA_INTERVAL_PROBE_TIME_MS:
2437				NEIGH_VAR_SET(p, INTERVAL_PROBE_TIME_MS,
2438					      nla_get_msecs(tbp[i]));
2439				break;
2440			case NDTPA_RETRANS_TIME:
2441				NEIGH_VAR_SET(p, RETRANS_TIME,
2442					      nla_get_msecs(tbp[i]));
2443				break;
2444			case NDTPA_ANYCAST_DELAY:
2445				NEIGH_VAR_SET(p, ANYCAST_DELAY,
2446					      nla_get_msecs(tbp[i]));
2447				break;
2448			case NDTPA_PROXY_DELAY:
2449				NEIGH_VAR_SET(p, PROXY_DELAY,
2450					      nla_get_msecs(tbp[i]));
2451				break;
2452			case NDTPA_LOCKTIME:
2453				NEIGH_VAR_SET(p, LOCKTIME,
2454					      nla_get_msecs(tbp[i]));
2455				break;
2456			}
2457		}
2458	}
2459
2460	err = -ENOENT;
2461	if ((tb[NDTA_THRESH1] || tb[NDTA_THRESH2] ||
2462	     tb[NDTA_THRESH3] || tb[NDTA_GC_INTERVAL]) &&
2463	    !net_eq(net, &init_net))
2464		goto errout_tbl_lock;
2465
2466	if (tb[NDTA_THRESH1])
2467		tbl->gc_thresh1 = nla_get_u32(tb[NDTA_THRESH1]);
2468
2469	if (tb[NDTA_THRESH2])
2470		tbl->gc_thresh2 = nla_get_u32(tb[NDTA_THRESH2]);
2471
2472	if (tb[NDTA_THRESH3])
2473		tbl->gc_thresh3 = nla_get_u32(tb[NDTA_THRESH3]);
2474
2475	if (tb[NDTA_GC_INTERVAL])
2476		tbl->gc_interval = nla_get_msecs(tb[NDTA_GC_INTERVAL]);
2477
2478	err = 0;
2479
2480errout_tbl_lock:
2481	write_unlock_bh(&tbl->lock);
2482errout:
2483	return err;
2484}
2485
2486static int neightbl_valid_dump_info(const struct nlmsghdr *nlh,
2487				    struct netlink_ext_ack *extack)
2488{
2489	struct ndtmsg *ndtm;
2490
2491	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndtm))) {
2492		NL_SET_ERR_MSG(extack, "Invalid header for neighbor table dump request");
2493		return -EINVAL;
2494	}
2495
2496	ndtm = nlmsg_data(nlh);
2497	if (ndtm->ndtm_pad1  || ndtm->ndtm_pad2) {
2498		NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor table dump request");
2499		return -EINVAL;
2500	}
2501
2502	if (nlmsg_attrlen(nlh, sizeof(*ndtm))) {
2503		NL_SET_ERR_MSG(extack, "Invalid data after header in neighbor table dump request");
2504		return -EINVAL;
2505	}
2506
2507	return 0;
2508}
2509
2510static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2511{
2512	const struct nlmsghdr *nlh = cb->nlh;
2513	struct net *net = sock_net(skb->sk);
2514	int family, tidx, nidx = 0;
2515	int tbl_skip = cb->args[0];
2516	int neigh_skip = cb->args[1];
2517	struct neigh_table *tbl;
2518
2519	if (cb->strict_check) {
2520		int err = neightbl_valid_dump_info(nlh, cb->extack);
2521
2522		if (err < 0)
2523			return err;
2524	}
2525
2526	family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family;
2527
2528	for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
2529		struct neigh_parms *p;
2530
2531		tbl = neigh_tables[tidx];
2532		if (!tbl)
2533			continue;
2534
2535		if (tidx < tbl_skip || (family && tbl->family != family))
2536			continue;
2537
2538		if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).portid,
2539				       nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
2540				       NLM_F_MULTI) < 0)
2541			break;
2542
2543		nidx = 0;
2544		p = list_next_entry(&tbl->parms, list);
2545		list_for_each_entry_from(p, &tbl->parms_list, list) {
2546			if (!net_eq(neigh_parms_net(p), net))
2547				continue;
2548
2549			if (nidx < neigh_skip)
2550				goto next;
2551
2552			if (neightbl_fill_param_info(skb, tbl, p,
2553						     NETLINK_CB(cb->skb).portid,
2554						     nlh->nlmsg_seq,
2555						     RTM_NEWNEIGHTBL,
2556						     NLM_F_MULTI) < 0)
2557				goto out;
2558		next:
2559			nidx++;
2560		}
2561
2562		neigh_skip = 0;
2563	}
2564out:
2565	cb->args[0] = tidx;
2566	cb->args[1] = nidx;
2567
2568	return skb->len;
2569}
2570
2571static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
2572			   u32 pid, u32 seq, int type, unsigned int flags)
2573{
2574	u32 neigh_flags, neigh_flags_ext;
2575	unsigned long now = jiffies;
2576	struct nda_cacheinfo ci;
2577	struct nlmsghdr *nlh;
2578	struct ndmsg *ndm;
2579
2580	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2581	if (nlh == NULL)
2582		return -EMSGSIZE;
2583
2584	neigh_flags_ext = neigh->flags >> NTF_EXT_SHIFT;
2585	neigh_flags     = neigh->flags & NTF_OLD_MASK;
2586
2587	ndm = nlmsg_data(nlh);
2588	ndm->ndm_family	 = neigh->ops->family;
2589	ndm->ndm_pad1    = 0;
2590	ndm->ndm_pad2    = 0;
2591	ndm->ndm_flags	 = neigh_flags;
2592	ndm->ndm_type	 = neigh->type;
2593	ndm->ndm_ifindex = neigh->dev->ifindex;
2594
2595	if (nla_put(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key))
2596		goto nla_put_failure;
2597
2598	read_lock_bh(&neigh->lock);
2599	ndm->ndm_state	 = neigh->nud_state;
2600	if (neigh->nud_state & NUD_VALID) {
2601		char haddr[MAX_ADDR_LEN];
2602
2603		neigh_ha_snapshot(haddr, neigh, neigh->dev);
2604		if (nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, haddr) < 0) {
2605			read_unlock_bh(&neigh->lock);
2606			goto nla_put_failure;
2607		}
2608	}
2609
2610	ci.ndm_used	 = jiffies_to_clock_t(now - neigh->used);
2611	ci.ndm_confirmed = jiffies_to_clock_t(now - neigh->confirmed);
2612	ci.ndm_updated	 = jiffies_to_clock_t(now - neigh->updated);
2613	ci.ndm_refcnt	 = refcount_read(&neigh->refcnt) - 1;
2614	read_unlock_bh(&neigh->lock);
2615
2616	if (nla_put_u32(skb, NDA_PROBES, atomic_read(&neigh->probes)) ||
2617	    nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
2618		goto nla_put_failure;
2619
2620	if (neigh->protocol && nla_put_u8(skb, NDA_PROTOCOL, neigh->protocol))
2621		goto nla_put_failure;
2622	if (neigh_flags_ext && nla_put_u32(skb, NDA_FLAGS_EXT, neigh_flags_ext))
2623		goto nla_put_failure;
2624
2625	nlmsg_end(skb, nlh);
2626	return 0;
2627
2628nla_put_failure:
2629	nlmsg_cancel(skb, nlh);
2630	return -EMSGSIZE;
2631}
2632
2633static int pneigh_fill_info(struct sk_buff *skb, struct pneigh_entry *pn,
2634			    u32 pid, u32 seq, int type, unsigned int flags,
2635			    struct neigh_table *tbl)
2636{
2637	u32 neigh_flags, neigh_flags_ext;
2638	struct nlmsghdr *nlh;
2639	struct ndmsg *ndm;
2640
2641	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2642	if (nlh == NULL)
2643		return -EMSGSIZE;
2644
2645	neigh_flags_ext = pn->flags >> NTF_EXT_SHIFT;
2646	neigh_flags     = pn->flags & NTF_OLD_MASK;
2647
2648	ndm = nlmsg_data(nlh);
2649	ndm->ndm_family	 = tbl->family;
2650	ndm->ndm_pad1    = 0;
2651	ndm->ndm_pad2    = 0;
2652	ndm->ndm_flags	 = neigh_flags | NTF_PROXY;
2653	ndm->ndm_type	 = RTN_UNICAST;
2654	ndm->ndm_ifindex = pn->dev ? pn->dev->ifindex : 0;
2655	ndm->ndm_state	 = NUD_NONE;
2656
2657	if (nla_put(skb, NDA_DST, tbl->key_len, pn->key))
2658		goto nla_put_failure;
2659
2660	if (pn->protocol && nla_put_u8(skb, NDA_PROTOCOL, pn->protocol))
2661		goto nla_put_failure;
2662	if (neigh_flags_ext && nla_put_u32(skb, NDA_FLAGS_EXT, neigh_flags_ext))
2663		goto nla_put_failure;
2664
2665	nlmsg_end(skb, nlh);
2666	return 0;
2667
2668nla_put_failure:
2669	nlmsg_cancel(skb, nlh);
2670	return -EMSGSIZE;
2671}
2672
2673static void neigh_update_notify(struct neighbour *neigh, u32 nlmsg_pid)
2674{
2675	call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
2676	__neigh_notify(neigh, RTM_NEWNEIGH, 0, nlmsg_pid);
2677}
2678
2679static bool neigh_master_filtered(struct net_device *dev, int master_idx)
2680{
2681	struct net_device *master;
2682
2683	if (!master_idx)
2684		return false;
2685
2686	master = dev ? netdev_master_upper_dev_get(dev) : NULL;
2687
2688	/* 0 is already used to denote NDA_MASTER wasn't passed, therefore need another
2689	 * invalid value for ifindex to denote "no master".
2690	 */
2691	if (master_idx == -1)
2692		return !!master;
2693
2694	if (!master || master->ifindex != master_idx)
2695		return true;
2696
2697	return false;
2698}
2699
2700static bool neigh_ifindex_filtered(struct net_device *dev, int filter_idx)
2701{
2702	if (filter_idx && (!dev || dev->ifindex != filter_idx))
2703		return true;
2704
2705	return false;
2706}
2707
2708struct neigh_dump_filter {
2709	int master_idx;
2710	int dev_idx;
2711};
2712
2713static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2714			    struct netlink_callback *cb,
2715			    struct neigh_dump_filter *filter)
2716{
2717	struct net *net = sock_net(skb->sk);
 
 
2718	struct neighbour *n;
2719	int rc, h, s_h = cb->args[1];
2720	int idx, s_idx = idx = cb->args[2];
2721	struct neigh_hash_table *nht;
 
2722	unsigned int flags = NLM_F_MULTI;
 
2723
2724	if (filter->dev_idx || filter->master_idx)
2725		flags |= NLM_F_DUMP_FILTERED;
 
 
 
 
 
 
 
 
 
2726
2727	rcu_read_lock_bh();
2728	nht = rcu_dereference_bh(tbl->nht);
2729
2730	for (h = s_h; h < (1 << nht->hash_shift); h++) {
2731		if (h > s_h)
2732			s_idx = 0;
2733		for (n = rcu_dereference_bh(nht->hash_buckets[h]), idx = 0;
2734		     n != NULL;
2735		     n = rcu_dereference_bh(n->next)) {
2736			if (idx < s_idx || !net_eq(dev_net(n->dev), net))
2737				goto next;
2738			if (neigh_ifindex_filtered(n->dev, filter->dev_idx) ||
2739			    neigh_master_filtered(n->dev, filter->master_idx))
 
 
 
2740				goto next;
2741			if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2742					    cb->nlh->nlmsg_seq,
2743					    RTM_NEWNEIGH,
2744					    flags) < 0) {
2745				rc = -1;
2746				goto out;
2747			}
2748next:
2749			idx++;
2750		}
2751	}
2752	rc = skb->len;
2753out:
2754	rcu_read_unlock_bh();
2755	cb->args[1] = h;
2756	cb->args[2] = idx;
2757	return rc;
2758}
2759
2760static int pneigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2761			     struct netlink_callback *cb,
2762			     struct neigh_dump_filter *filter)
2763{
2764	struct pneigh_entry *n;
2765	struct net *net = sock_net(skb->sk);
2766	int rc, h, s_h = cb->args[3];
2767	int idx, s_idx = idx = cb->args[4];
2768	unsigned int flags = NLM_F_MULTI;
2769
2770	if (filter->dev_idx || filter->master_idx)
2771		flags |= NLM_F_DUMP_FILTERED;
2772
2773	read_lock_bh(&tbl->lock);
2774
2775	for (h = s_h; h <= PNEIGH_HASHMASK; h++) {
2776		if (h > s_h)
2777			s_idx = 0;
2778		for (n = tbl->phash_buckets[h], idx = 0; n; n = n->next) {
2779			if (idx < s_idx || pneigh_net(n) != net)
2780				goto next;
2781			if (neigh_ifindex_filtered(n->dev, filter->dev_idx) ||
2782			    neigh_master_filtered(n->dev, filter->master_idx))
2783				goto next;
2784			if (pneigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2785					    cb->nlh->nlmsg_seq,
2786					    RTM_NEWNEIGH, flags, tbl) < 0) {
 
2787				read_unlock_bh(&tbl->lock);
2788				rc = -1;
2789				goto out;
2790			}
2791		next:
2792			idx++;
2793		}
2794	}
2795
2796	read_unlock_bh(&tbl->lock);
2797	rc = skb->len;
2798out:
2799	cb->args[3] = h;
2800	cb->args[4] = idx;
2801	return rc;
2802
2803}
2804
2805static int neigh_valid_dump_req(const struct nlmsghdr *nlh,
2806				bool strict_check,
2807				struct neigh_dump_filter *filter,
2808				struct netlink_ext_ack *extack)
2809{
2810	struct nlattr *tb[NDA_MAX + 1];
2811	int err, i;
2812
2813	if (strict_check) {
2814		struct ndmsg *ndm;
2815
2816		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) {
2817			NL_SET_ERR_MSG(extack, "Invalid header for neighbor dump request");
2818			return -EINVAL;
2819		}
2820
2821		ndm = nlmsg_data(nlh);
2822		if (ndm->ndm_pad1  || ndm->ndm_pad2  || ndm->ndm_ifindex ||
2823		    ndm->ndm_state || ndm->ndm_type) {
2824			NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor dump request");
2825			return -EINVAL;
2826		}
2827
2828		if (ndm->ndm_flags & ~NTF_PROXY) {
2829			NL_SET_ERR_MSG(extack, "Invalid flags in header for neighbor dump request");
2830			return -EINVAL;
2831		}
2832
2833		err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct ndmsg),
2834						    tb, NDA_MAX, nda_policy,
2835						    extack);
2836	} else {
2837		err = nlmsg_parse_deprecated(nlh, sizeof(struct ndmsg), tb,
2838					     NDA_MAX, nda_policy, extack);
2839	}
2840	if (err < 0)
2841		return err;
2842
2843	for (i = 0; i <= NDA_MAX; ++i) {
2844		if (!tb[i])
2845			continue;
2846
2847		/* all new attributes should require strict_check */
2848		switch (i) {
2849		case NDA_IFINDEX:
2850			filter->dev_idx = nla_get_u32(tb[i]);
2851			break;
2852		case NDA_MASTER:
2853			filter->master_idx = nla_get_u32(tb[i]);
2854			break;
2855		default:
2856			if (strict_check) {
2857				NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor dump request");
2858				return -EINVAL;
2859			}
2860		}
2861	}
2862
2863	return 0;
2864}
2865
2866static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2867{
2868	const struct nlmsghdr *nlh = cb->nlh;
2869	struct neigh_dump_filter filter = {};
2870	struct neigh_table *tbl;
2871	int t, family, s_t;
2872	int proxy = 0;
2873	int err;
2874
2875	family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family;
2876
2877	/* check for full ndmsg structure presence, family member is
2878	 * the same for both structures
2879	 */
2880	if (nlmsg_len(nlh) >= sizeof(struct ndmsg) &&
2881	    ((struct ndmsg *)nlmsg_data(nlh))->ndm_flags == NTF_PROXY)
2882		proxy = 1;
2883
2884	err = neigh_valid_dump_req(nlh, cb->strict_check, &filter, cb->extack);
2885	if (err < 0 && cb->strict_check)
2886		return err;
2887
2888	s_t = cb->args[0];
2889
2890	for (t = 0; t < NEIGH_NR_TABLES; t++) {
2891		tbl = neigh_tables[t];
2892
2893		if (!tbl)
2894			continue;
2895		if (t < s_t || (family && tbl->family != family))
2896			continue;
2897		if (t > s_t)
2898			memset(&cb->args[1], 0, sizeof(cb->args) -
2899						sizeof(cb->args[0]));
2900		if (proxy)
2901			err = pneigh_dump_table(tbl, skb, cb, &filter);
2902		else
2903			err = neigh_dump_table(tbl, skb, cb, &filter);
2904		if (err < 0)
2905			break;
2906	}
2907
2908	cb->args[0] = t;
2909	return skb->len;
2910}
2911
2912static int neigh_valid_get_req(const struct nlmsghdr *nlh,
2913			       struct neigh_table **tbl,
2914			       void **dst, int *dev_idx, u8 *ndm_flags,
2915			       struct netlink_ext_ack *extack)
2916{
2917	struct nlattr *tb[NDA_MAX + 1];
2918	struct ndmsg *ndm;
2919	int err, i;
2920
2921	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) {
2922		NL_SET_ERR_MSG(extack, "Invalid header for neighbor get request");
2923		return -EINVAL;
2924	}
2925
2926	ndm = nlmsg_data(nlh);
2927	if (ndm->ndm_pad1  || ndm->ndm_pad2  || ndm->ndm_state ||
2928	    ndm->ndm_type) {
2929		NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor get request");
2930		return -EINVAL;
2931	}
2932
2933	if (ndm->ndm_flags & ~NTF_PROXY) {
2934		NL_SET_ERR_MSG(extack, "Invalid flags in header for neighbor get request");
2935		return -EINVAL;
2936	}
2937
2938	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct ndmsg), tb,
2939					    NDA_MAX, nda_policy, extack);
2940	if (err < 0)
2941		return err;
2942
2943	*ndm_flags = ndm->ndm_flags;
2944	*dev_idx = ndm->ndm_ifindex;
2945	*tbl = neigh_find_table(ndm->ndm_family);
2946	if (*tbl == NULL) {
2947		NL_SET_ERR_MSG(extack, "Unsupported family in header for neighbor get request");
2948		return -EAFNOSUPPORT;
2949	}
2950
2951	for (i = 0; i <= NDA_MAX; ++i) {
2952		if (!tb[i])
2953			continue;
2954
2955		switch (i) {
2956		case NDA_DST:
2957			if (nla_len(tb[i]) != (int)(*tbl)->key_len) {
2958				NL_SET_ERR_MSG(extack, "Invalid network address in neighbor get request");
2959				return -EINVAL;
2960			}
2961			*dst = nla_data(tb[i]);
2962			break;
2963		default:
2964			NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor get request");
2965			return -EINVAL;
2966		}
2967	}
2968
2969	return 0;
2970}
2971
2972static inline size_t neigh_nlmsg_size(void)
2973{
2974	return NLMSG_ALIGN(sizeof(struct ndmsg))
2975	       + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2976	       + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */
2977	       + nla_total_size(sizeof(struct nda_cacheinfo))
2978	       + nla_total_size(4)  /* NDA_PROBES */
2979	       + nla_total_size(4)  /* NDA_FLAGS_EXT */
2980	       + nla_total_size(1); /* NDA_PROTOCOL */
2981}
2982
2983static int neigh_get_reply(struct net *net, struct neighbour *neigh,
2984			   u32 pid, u32 seq)
2985{
2986	struct sk_buff *skb;
2987	int err = 0;
2988
2989	skb = nlmsg_new(neigh_nlmsg_size(), GFP_KERNEL);
2990	if (!skb)
2991		return -ENOBUFS;
2992
2993	err = neigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0);
2994	if (err) {
2995		kfree_skb(skb);
2996		goto errout;
2997	}
2998
2999	err = rtnl_unicast(skb, net, pid);
3000errout:
3001	return err;
3002}
3003
3004static inline size_t pneigh_nlmsg_size(void)
3005{
3006	return NLMSG_ALIGN(sizeof(struct ndmsg))
3007	       + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
3008	       + nla_total_size(4)  /* NDA_FLAGS_EXT */
3009	       + nla_total_size(1); /* NDA_PROTOCOL */
3010}
3011
3012static int pneigh_get_reply(struct net *net, struct pneigh_entry *neigh,
3013			    u32 pid, u32 seq, struct neigh_table *tbl)
3014{
3015	struct sk_buff *skb;
3016	int err = 0;
3017
3018	skb = nlmsg_new(pneigh_nlmsg_size(), GFP_KERNEL);
3019	if (!skb)
3020		return -ENOBUFS;
3021
3022	err = pneigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0, tbl);
3023	if (err) {
3024		kfree_skb(skb);
3025		goto errout;
3026	}
3027
3028	err = rtnl_unicast(skb, net, pid);
3029errout:
3030	return err;
3031}
3032
3033static int neigh_get(struct sk_buff *in_skb, struct nlmsghdr *nlh,
3034		     struct netlink_ext_ack *extack)
3035{
3036	struct net *net = sock_net(in_skb->sk);
3037	struct net_device *dev = NULL;
3038	struct neigh_table *tbl = NULL;
3039	struct neighbour *neigh;
3040	void *dst = NULL;
3041	u8 ndm_flags = 0;
3042	int dev_idx = 0;
3043	int err;
3044
3045	err = neigh_valid_get_req(nlh, &tbl, &dst, &dev_idx, &ndm_flags,
3046				  extack);
3047	if (err < 0)
3048		return err;
3049
3050	if (dev_idx) {
3051		dev = __dev_get_by_index(net, dev_idx);
3052		if (!dev) {
3053			NL_SET_ERR_MSG(extack, "Unknown device ifindex");
3054			return -ENODEV;
3055		}
3056	}
3057
3058	if (!dst) {
3059		NL_SET_ERR_MSG(extack, "Network address not specified");
3060		return -EINVAL;
3061	}
3062
3063	if (ndm_flags & NTF_PROXY) {
3064		struct pneigh_entry *pn;
3065
3066		pn = pneigh_lookup(tbl, net, dst, dev, 0);
3067		if (!pn) {
3068			NL_SET_ERR_MSG(extack, "Proxy neighbour entry not found");
3069			return -ENOENT;
3070		}
3071		return pneigh_get_reply(net, pn, NETLINK_CB(in_skb).portid,
3072					nlh->nlmsg_seq, tbl);
3073	}
3074
3075	if (!dev) {
3076		NL_SET_ERR_MSG(extack, "No device specified");
3077		return -EINVAL;
3078	}
3079
3080	neigh = neigh_lookup(tbl, dst, dev);
3081	if (!neigh) {
3082		NL_SET_ERR_MSG(extack, "Neighbour entry not found");
3083		return -ENOENT;
3084	}
3085
3086	err = neigh_get_reply(net, neigh, NETLINK_CB(in_skb).portid,
3087			      nlh->nlmsg_seq);
3088
3089	neigh_release(neigh);
3090
3091	return err;
3092}
3093
3094void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
3095{
3096	int chain;
3097	struct neigh_hash_table *nht;
3098
3099	rcu_read_lock_bh();
3100	nht = rcu_dereference_bh(tbl->nht);
3101
3102	read_lock(&tbl->lock); /* avoid resizes */
3103	for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
3104		struct neighbour *n;
3105
3106		for (n = rcu_dereference_bh(nht->hash_buckets[chain]);
3107		     n != NULL;
3108		     n = rcu_dereference_bh(n->next))
3109			cb(n, cookie);
3110	}
3111	read_unlock(&tbl->lock);
3112	rcu_read_unlock_bh();
3113}
3114EXPORT_SYMBOL(neigh_for_each);
3115
3116/* The tbl->lock must be held as a writer and BH disabled. */
3117void __neigh_for_each_release(struct neigh_table *tbl,
3118			      int (*cb)(struct neighbour *))
3119{
3120	int chain;
3121	struct neigh_hash_table *nht;
3122
3123	nht = rcu_dereference_protected(tbl->nht,
3124					lockdep_is_held(&tbl->lock));
3125	for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
3126		struct neighbour *n;
3127		struct neighbour __rcu **np;
3128
3129		np = &nht->hash_buckets[chain];
3130		while ((n = rcu_dereference_protected(*np,
3131					lockdep_is_held(&tbl->lock))) != NULL) {
3132			int release;
3133
3134			write_lock(&n->lock);
3135			release = cb(n);
3136			if (release) {
3137				rcu_assign_pointer(*np,
3138					rcu_dereference_protected(n->next,
3139						lockdep_is_held(&tbl->lock)));
3140				neigh_mark_dead(n);
3141			} else
3142				np = &n->next;
3143			write_unlock(&n->lock);
3144			if (release)
3145				neigh_cleanup_and_release(n);
3146		}
3147	}
3148}
3149EXPORT_SYMBOL(__neigh_for_each_release);
3150
3151int neigh_xmit(int index, struct net_device *dev,
3152	       const void *addr, struct sk_buff *skb)
3153{
3154	int err = -EAFNOSUPPORT;
3155	if (likely(index < NEIGH_NR_TABLES)) {
3156		struct neigh_table *tbl;
3157		struct neighbour *neigh;
3158
3159		tbl = neigh_tables[index];
3160		if (!tbl)
3161			goto out;
3162		rcu_read_lock_bh();
3163		if (index == NEIGH_ARP_TABLE) {
3164			u32 key = *((u32 *)addr);
3165
3166			neigh = __ipv4_neigh_lookup_noref(dev, key);
3167		} else {
3168			neigh = __neigh_lookup_noref(tbl, addr, dev);
3169		}
3170		if (!neigh)
3171			neigh = __neigh_create(tbl, addr, dev, false);
3172		err = PTR_ERR(neigh);
3173		if (IS_ERR(neigh)) {
3174			rcu_read_unlock_bh();
3175			goto out_kfree_skb;
3176		}
3177		err = neigh->output(neigh, skb);
3178		rcu_read_unlock_bh();
3179	}
3180	else if (index == NEIGH_LINK_TABLE) {
3181		err = dev_hard_header(skb, dev, ntohs(skb->protocol),
3182				      addr, NULL, skb->len);
3183		if (err < 0)
3184			goto out_kfree_skb;
3185		err = dev_queue_xmit(skb);
3186	}
3187out:
3188	return err;
3189out_kfree_skb:
3190	kfree_skb(skb);
3191	goto out;
3192}
3193EXPORT_SYMBOL(neigh_xmit);
3194
3195#ifdef CONFIG_PROC_FS
3196
3197static struct neighbour *neigh_get_first(struct seq_file *seq)
3198{
3199	struct neigh_seq_state *state = seq->private;
3200	struct net *net = seq_file_net(seq);
3201	struct neigh_hash_table *nht = state->nht;
3202	struct neighbour *n = NULL;
3203	int bucket;
3204
3205	state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
3206	for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) {
3207		n = rcu_dereference_bh(nht->hash_buckets[bucket]);
3208
3209		while (n) {
3210			if (!net_eq(dev_net(n->dev), net))
3211				goto next;
3212			if (state->neigh_sub_iter) {
3213				loff_t fakep = 0;
3214				void *v;
3215
3216				v = state->neigh_sub_iter(state, n, &fakep);
3217				if (!v)
3218					goto next;
3219			}
3220			if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
3221				break;
3222			if (n->nud_state & ~NUD_NOARP)
3223				break;
3224next:
3225			n = rcu_dereference_bh(n->next);
3226		}
3227
3228		if (n)
3229			break;
3230	}
3231	state->bucket = bucket;
3232
3233	return n;
3234}
3235
3236static struct neighbour *neigh_get_next(struct seq_file *seq,
3237					struct neighbour *n,
3238					loff_t *pos)
3239{
3240	struct neigh_seq_state *state = seq->private;
3241	struct net *net = seq_file_net(seq);
3242	struct neigh_hash_table *nht = state->nht;
3243
3244	if (state->neigh_sub_iter) {
3245		void *v = state->neigh_sub_iter(state, n, pos);
3246		if (v)
3247			return n;
3248	}
3249	n = rcu_dereference_bh(n->next);
3250
3251	while (1) {
3252		while (n) {
3253			if (!net_eq(dev_net(n->dev), net))
3254				goto next;
3255			if (state->neigh_sub_iter) {
3256				void *v = state->neigh_sub_iter(state, n, pos);
3257				if (v)
3258					return n;
3259				goto next;
3260			}
3261			if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
3262				break;
3263
3264			if (n->nud_state & ~NUD_NOARP)
3265				break;
3266next:
3267			n = rcu_dereference_bh(n->next);
3268		}
3269
3270		if (n)
3271			break;
3272
3273		if (++state->bucket >= (1 << nht->hash_shift))
3274			break;
3275
3276		n = rcu_dereference_bh(nht->hash_buckets[state->bucket]);
3277	}
3278
3279	if (n && pos)
3280		--(*pos);
3281	return n;
3282}
3283
3284static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
3285{
3286	struct neighbour *n = neigh_get_first(seq);
3287
3288	if (n) {
3289		--(*pos);
3290		while (*pos) {
3291			n = neigh_get_next(seq, n, pos);
3292			if (!n)
3293				break;
3294		}
3295	}
3296	return *pos ? NULL : n;
3297}
3298
3299static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
3300{
3301	struct neigh_seq_state *state = seq->private;
3302	struct net *net = seq_file_net(seq);
3303	struct neigh_table *tbl = state->tbl;
3304	struct pneigh_entry *pn = NULL;
3305	int bucket;
3306
3307	state->flags |= NEIGH_SEQ_IS_PNEIGH;
3308	for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
3309		pn = tbl->phash_buckets[bucket];
3310		while (pn && !net_eq(pneigh_net(pn), net))
3311			pn = pn->next;
3312		if (pn)
3313			break;
3314	}
3315	state->bucket = bucket;
3316
3317	return pn;
3318}
3319
3320static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
3321					    struct pneigh_entry *pn,
3322					    loff_t *pos)
3323{
3324	struct neigh_seq_state *state = seq->private;
3325	struct net *net = seq_file_net(seq);
3326	struct neigh_table *tbl = state->tbl;
3327
3328	do {
3329		pn = pn->next;
3330	} while (pn && !net_eq(pneigh_net(pn), net));
3331
3332	while (!pn) {
3333		if (++state->bucket > PNEIGH_HASHMASK)
3334			break;
3335		pn = tbl->phash_buckets[state->bucket];
3336		while (pn && !net_eq(pneigh_net(pn), net))
3337			pn = pn->next;
3338		if (pn)
3339			break;
3340	}
3341
3342	if (pn && pos)
3343		--(*pos);
3344
3345	return pn;
3346}
3347
3348static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
3349{
3350	struct pneigh_entry *pn = pneigh_get_first(seq);
3351
3352	if (pn) {
3353		--(*pos);
3354		while (*pos) {
3355			pn = pneigh_get_next(seq, pn, pos);
3356			if (!pn)
3357				break;
3358		}
3359	}
3360	return *pos ? NULL : pn;
3361}
3362
3363static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
3364{
3365	struct neigh_seq_state *state = seq->private;
3366	void *rc;
3367	loff_t idxpos = *pos;
3368
3369	rc = neigh_get_idx(seq, &idxpos);
3370	if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
3371		rc = pneigh_get_idx(seq, &idxpos);
3372
3373	return rc;
3374}
3375
3376void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
3377	__acquires(tbl->lock)
3378	__acquires(rcu_bh)
3379{
3380	struct neigh_seq_state *state = seq->private;
3381
3382	state->tbl = tbl;
3383	state->bucket = 0;
3384	state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
3385
3386	rcu_read_lock_bh();
3387	state->nht = rcu_dereference_bh(tbl->nht);
3388	read_lock(&tbl->lock);
3389
3390	return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
3391}
3392EXPORT_SYMBOL(neigh_seq_start);
3393
3394void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3395{
3396	struct neigh_seq_state *state;
3397	void *rc;
3398
3399	if (v == SEQ_START_TOKEN) {
3400		rc = neigh_get_first(seq);
3401		goto out;
3402	}
3403
3404	state = seq->private;
3405	if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
3406		rc = neigh_get_next(seq, v, NULL);
3407		if (rc)
3408			goto out;
3409		if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
3410			rc = pneigh_get_first(seq);
3411	} else {
3412		BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
3413		rc = pneigh_get_next(seq, v, NULL);
3414	}
3415out:
3416	++(*pos);
3417	return rc;
3418}
3419EXPORT_SYMBOL(neigh_seq_next);
3420
3421void neigh_seq_stop(struct seq_file *seq, void *v)
3422	__releases(tbl->lock)
3423	__releases(rcu_bh)
3424{
3425	struct neigh_seq_state *state = seq->private;
3426	struct neigh_table *tbl = state->tbl;
3427
3428	read_unlock(&tbl->lock);
3429	rcu_read_unlock_bh();
3430}
3431EXPORT_SYMBOL(neigh_seq_stop);
3432
3433/* statistics via seq_file */
3434
3435static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
3436{
3437	struct neigh_table *tbl = pde_data(file_inode(seq->file));
3438	int cpu;
3439
3440	if (*pos == 0)
3441		return SEQ_START_TOKEN;
3442
3443	for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
3444		if (!cpu_possible(cpu))
3445			continue;
3446		*pos = cpu+1;
3447		return per_cpu_ptr(tbl->stats, cpu);
3448	}
3449	return NULL;
3450}
3451
3452static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3453{
3454	struct neigh_table *tbl = pde_data(file_inode(seq->file));
3455	int cpu;
3456
3457	for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
3458		if (!cpu_possible(cpu))
3459			continue;
3460		*pos = cpu+1;
3461		return per_cpu_ptr(tbl->stats, cpu);
3462	}
3463	(*pos)++;
3464	return NULL;
3465}
3466
3467static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
3468{
3469
3470}
3471
3472static int neigh_stat_seq_show(struct seq_file *seq, void *v)
3473{
3474	struct neigh_table *tbl = pde_data(file_inode(seq->file));
3475	struct neigh_statistics *st = v;
3476
3477	if (v == SEQ_START_TOKEN) {
3478		seq_puts(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");
3479		return 0;
3480	}
3481
3482	seq_printf(seq, "%08x %08lx %08lx %08lx   %08lx %08lx %08lx   "
3483			"%08lx         %08lx         %08lx         "
3484			"%08lx       %08lx            %08lx\n",
3485		   atomic_read(&tbl->entries),
3486
3487		   st->allocs,
3488		   st->destroys,
3489		   st->hash_grows,
3490
3491		   st->lookups,
3492		   st->hits,
3493
3494		   st->res_failed,
3495
3496		   st->rcv_probes_mcast,
3497		   st->rcv_probes_ucast,
3498
3499		   st->periodic_gc_runs,
3500		   st->forced_gc_runs,
3501		   st->unres_discards,
3502		   st->table_fulls
3503		   );
3504
3505	return 0;
3506}
3507
3508static const struct seq_operations neigh_stat_seq_ops = {
3509	.start	= neigh_stat_seq_start,
3510	.next	= neigh_stat_seq_next,
3511	.stop	= neigh_stat_seq_stop,
3512	.show	= neigh_stat_seq_show,
3513};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3514#endif /* CONFIG_PROC_FS */
3515
3516static void __neigh_notify(struct neighbour *n, int type, int flags,
3517			   u32 pid)
 
 
 
 
 
 
 
 
3518{
3519	struct net *net = dev_net(n->dev);
3520	struct sk_buff *skb;
3521	int err = -ENOBUFS;
3522
3523	skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
3524	if (skb == NULL)
3525		goto errout;
3526
3527	err = neigh_fill_info(skb, n, pid, 0, type, flags);
3528	if (err < 0) {
3529		/* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
3530		WARN_ON(err == -EMSGSIZE);
3531		kfree_skb(skb);
3532		goto errout;
3533	}
3534	rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
3535	return;
3536errout:
3537	if (err < 0)
3538		rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
3539}
3540
3541void neigh_app_ns(struct neighbour *n)
3542{
3543	__neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST, 0);
3544}
3545EXPORT_SYMBOL(neigh_app_ns);
3546
3547#ifdef CONFIG_SYSCTL
 
 
3548static int unres_qlen_max = INT_MAX / SKB_TRUESIZE(ETH_FRAME_LEN);
3549
3550static int proc_unres_qlen(struct ctl_table *ctl, int write,
3551			   void *buffer, size_t *lenp, loff_t *ppos)
3552{
3553	int size, ret;
3554	struct ctl_table tmp = *ctl;
3555
3556	tmp.extra1 = SYSCTL_ZERO;
3557	tmp.extra2 = &unres_qlen_max;
3558	tmp.data = &size;
3559
3560	size = *(int *)ctl->data / SKB_TRUESIZE(ETH_FRAME_LEN);
3561	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
3562
3563	if (write && !ret)
3564		*(int *)ctl->data = size * SKB_TRUESIZE(ETH_FRAME_LEN);
3565	return ret;
3566}
3567
 
 
 
 
 
 
 
 
 
 
 
 
3568static void neigh_copy_dflt_parms(struct net *net, struct neigh_parms *p,
3569				  int index)
3570{
3571	struct net_device *dev;
3572	int family = neigh_parms_family(p);
3573
3574	rcu_read_lock();
3575	for_each_netdev_rcu(net, dev) {
3576		struct neigh_parms *dst_p =
3577				neigh_get_dev_parms_rcu(dev, family);
3578
3579		if (dst_p && !test_bit(index, dst_p->data_state))
3580			dst_p->data[index] = p->data[index];
3581	}
3582	rcu_read_unlock();
3583}
3584
3585static void neigh_proc_update(struct ctl_table *ctl, int write)
3586{
3587	struct net_device *dev = ctl->extra1;
3588	struct neigh_parms *p = ctl->extra2;
3589	struct net *net = neigh_parms_net(p);
3590	int index = (int *) ctl->data - p->data;
3591
3592	if (!write)
3593		return;
3594
3595	set_bit(index, p->data_state);
3596	if (index == NEIGH_VAR_DELAY_PROBE_TIME)
3597		call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
3598	if (!dev) /* NULL dev means this is default value */
3599		neigh_copy_dflt_parms(net, p, index);
3600}
3601
3602static int neigh_proc_dointvec_zero_intmax(struct ctl_table *ctl, int write,
3603					   void *buffer, size_t *lenp,
3604					   loff_t *ppos)
3605{
3606	struct ctl_table tmp = *ctl;
3607	int ret;
3608
3609	tmp.extra1 = SYSCTL_ZERO;
3610	tmp.extra2 = SYSCTL_INT_MAX;
3611
3612	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
3613	neigh_proc_update(ctl, write);
3614	return ret;
3615}
3616
3617static int neigh_proc_dointvec_ms_jiffies_positive(struct ctl_table *ctl, int write,
3618						   void *buffer, size_t *lenp, loff_t *ppos)
3619{
3620	struct ctl_table tmp = *ctl;
3621	int ret;
3622
3623	int min = msecs_to_jiffies(1);
3624
3625	tmp.extra1 = &min;
3626	tmp.extra2 = NULL;
3627
3628	ret = proc_dointvec_ms_jiffies_minmax(&tmp, write, buffer, lenp, ppos);
3629	neigh_proc_update(ctl, write);
3630	return ret;
3631}
3632
3633int neigh_proc_dointvec(struct ctl_table *ctl, int write, void *buffer,
3634			size_t *lenp, loff_t *ppos)
3635{
3636	int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
3637
3638	neigh_proc_update(ctl, write);
3639	return ret;
3640}
3641EXPORT_SYMBOL(neigh_proc_dointvec);
3642
3643int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write, void *buffer,
 
3644				size_t *lenp, loff_t *ppos)
3645{
3646	int ret = proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
3647
3648	neigh_proc_update(ctl, write);
3649	return ret;
3650}
3651EXPORT_SYMBOL(neigh_proc_dointvec_jiffies);
3652
3653static int neigh_proc_dointvec_userhz_jiffies(struct ctl_table *ctl, int write,
3654					      void *buffer, size_t *lenp,
3655					      loff_t *ppos)
3656{
3657	int ret = proc_dointvec_userhz_jiffies(ctl, write, buffer, lenp, ppos);
3658
3659	neigh_proc_update(ctl, write);
3660	return ret;
3661}
3662
3663int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
3664				   void *buffer, size_t *lenp, loff_t *ppos)
 
3665{
3666	int ret = proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
3667
3668	neigh_proc_update(ctl, write);
3669	return ret;
3670}
3671EXPORT_SYMBOL(neigh_proc_dointvec_ms_jiffies);
3672
3673static int neigh_proc_dointvec_unres_qlen(struct ctl_table *ctl, int write,
3674					  void *buffer, size_t *lenp,
3675					  loff_t *ppos)
3676{
3677	int ret = proc_unres_qlen(ctl, write, buffer, lenp, ppos);
3678
3679	neigh_proc_update(ctl, write);
3680	return ret;
3681}
3682
3683static int neigh_proc_base_reachable_time(struct ctl_table *ctl, int write,
3684					  void *buffer, size_t *lenp,
3685					  loff_t *ppos)
3686{
3687	struct neigh_parms *p = ctl->extra2;
3688	int ret;
3689
3690	if (strcmp(ctl->procname, "base_reachable_time") == 0)
3691		ret = neigh_proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
3692	else if (strcmp(ctl->procname, "base_reachable_time_ms") == 0)
3693		ret = neigh_proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
3694	else
3695		ret = -1;
3696
3697	if (write && ret == 0) {
3698		/* update reachable_time as well, otherwise, the change will
3699		 * only be effective after the next time neigh_periodic_work
3700		 * decides to recompute it
3701		 */
3702		p->reachable_time =
3703			neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
3704	}
3705	return ret;
3706}
3707
3708#define NEIGH_PARMS_DATA_OFFSET(index)	\
3709	(&((struct neigh_parms *) 0)->data[index])
3710
3711#define NEIGH_SYSCTL_ENTRY(attr, data_attr, name, mval, proc) \
3712	[NEIGH_VAR_ ## attr] = { \
3713		.procname	= name, \
3714		.data		= NEIGH_PARMS_DATA_OFFSET(NEIGH_VAR_ ## data_attr), \
3715		.maxlen		= sizeof(int), \
3716		.mode		= mval, \
3717		.proc_handler	= proc, \
3718	}
3719
3720#define NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(attr, name) \
3721	NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_zero_intmax)
3722
3723#define NEIGH_SYSCTL_JIFFIES_ENTRY(attr, name) \
3724	NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_jiffies)
3725
3726#define NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(attr, name) \
3727	NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_userhz_jiffies)
3728
3729#define NEIGH_SYSCTL_MS_JIFFIES_POSITIVE_ENTRY(attr, name) \
3730	NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_ms_jiffies_positive)
3731
3732#define NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(attr, data_attr, name) \
3733	NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_ms_jiffies)
3734
3735#define NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(attr, data_attr, name) \
3736	NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_unres_qlen)
3737
3738static struct neigh_sysctl_table {
3739	struct ctl_table_header *sysctl_header;
3740	struct ctl_table neigh_vars[NEIGH_VAR_MAX + 1];
3741} neigh_sysctl_template __read_mostly = {
3742	.neigh_vars = {
3743		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_PROBES, "mcast_solicit"),
3744		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(UCAST_PROBES, "ucast_solicit"),
3745		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(APP_PROBES, "app_solicit"),
3746		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_REPROBES, "mcast_resolicit"),
3747		NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(RETRANS_TIME, "retrans_time"),
3748		NEIGH_SYSCTL_JIFFIES_ENTRY(BASE_REACHABLE_TIME, "base_reachable_time"),
3749		NEIGH_SYSCTL_JIFFIES_ENTRY(DELAY_PROBE_TIME, "delay_first_probe_time"),
3750		NEIGH_SYSCTL_MS_JIFFIES_POSITIVE_ENTRY(INTERVAL_PROBE_TIME_MS,
3751						       "interval_probe_time_ms"),
3752		NEIGH_SYSCTL_JIFFIES_ENTRY(GC_STALETIME, "gc_stale_time"),
3753		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(QUEUE_LEN_BYTES, "unres_qlen_bytes"),
3754		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(PROXY_QLEN, "proxy_qlen"),
3755		NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(ANYCAST_DELAY, "anycast_delay"),
3756		NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(PROXY_DELAY, "proxy_delay"),
3757		NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(LOCKTIME, "locktime"),
3758		NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(QUEUE_LEN, QUEUE_LEN_BYTES, "unres_qlen"),
3759		NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(RETRANS_TIME_MS, RETRANS_TIME, "retrans_time_ms"),
3760		NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(BASE_REACHABLE_TIME_MS, BASE_REACHABLE_TIME, "base_reachable_time_ms"),
3761		[NEIGH_VAR_GC_INTERVAL] = {
3762			.procname	= "gc_interval",
3763			.maxlen		= sizeof(int),
3764			.mode		= 0644,
3765			.proc_handler	= proc_dointvec_jiffies,
3766		},
3767		[NEIGH_VAR_GC_THRESH1] = {
3768			.procname	= "gc_thresh1",
3769			.maxlen		= sizeof(int),
3770			.mode		= 0644,
3771			.extra1		= SYSCTL_ZERO,
3772			.extra2		= SYSCTL_INT_MAX,
3773			.proc_handler	= proc_dointvec_minmax,
3774		},
3775		[NEIGH_VAR_GC_THRESH2] = {
3776			.procname	= "gc_thresh2",
3777			.maxlen		= sizeof(int),
3778			.mode		= 0644,
3779			.extra1		= SYSCTL_ZERO,
3780			.extra2		= SYSCTL_INT_MAX,
3781			.proc_handler	= proc_dointvec_minmax,
3782		},
3783		[NEIGH_VAR_GC_THRESH3] = {
3784			.procname	= "gc_thresh3",
3785			.maxlen		= sizeof(int),
3786			.mode		= 0644,
3787			.extra1		= SYSCTL_ZERO,
3788			.extra2		= SYSCTL_INT_MAX,
3789			.proc_handler	= proc_dointvec_minmax,
3790		},
3791		{},
3792	},
3793};
3794
3795int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
3796			  proc_handler *handler)
3797{
3798	int i;
3799	struct neigh_sysctl_table *t;
3800	const char *dev_name_source;
3801	char neigh_path[ sizeof("net//neigh/") + IFNAMSIZ + IFNAMSIZ ];
3802	char *p_name;
3803
3804	t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL_ACCOUNT);
3805	if (!t)
3806		goto err;
3807
3808	for (i = 0; i < NEIGH_VAR_GC_INTERVAL; i++) {
3809		t->neigh_vars[i].data += (long) p;
3810		t->neigh_vars[i].extra1 = dev;
3811		t->neigh_vars[i].extra2 = p;
3812	}
3813
3814	if (dev) {
3815		dev_name_source = dev->name;
3816		/* Terminate the table early */
3817		memset(&t->neigh_vars[NEIGH_VAR_GC_INTERVAL], 0,
3818		       sizeof(t->neigh_vars[NEIGH_VAR_GC_INTERVAL]));
3819	} else {
3820		struct neigh_table *tbl = p->tbl;
3821		dev_name_source = "default";
3822		t->neigh_vars[NEIGH_VAR_GC_INTERVAL].data = &tbl->gc_interval;
3823		t->neigh_vars[NEIGH_VAR_GC_THRESH1].data = &tbl->gc_thresh1;
3824		t->neigh_vars[NEIGH_VAR_GC_THRESH2].data = &tbl->gc_thresh2;
3825		t->neigh_vars[NEIGH_VAR_GC_THRESH3].data = &tbl->gc_thresh3;
3826	}
3827
3828	if (handler) {
3829		/* RetransTime */
3830		t->neigh_vars[NEIGH_VAR_RETRANS_TIME].proc_handler = handler;
3831		/* ReachableTime */
3832		t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler = handler;
3833		/* RetransTime (in milliseconds)*/
3834		t->neigh_vars[NEIGH_VAR_RETRANS_TIME_MS].proc_handler = handler;
3835		/* ReachableTime (in milliseconds) */
3836		t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler = handler;
3837	} else {
3838		/* Those handlers will update p->reachable_time after
3839		 * base_reachable_time(_ms) is set to ensure the new timer starts being
3840		 * applied after the next neighbour update instead of waiting for
3841		 * neigh_periodic_work to update its value (can be multiple minutes)
3842		 * So any handler that replaces them should do this as well
3843		 */
3844		/* ReachableTime */
3845		t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler =
3846			neigh_proc_base_reachable_time;
3847		/* ReachableTime (in milliseconds) */
3848		t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler =
3849			neigh_proc_base_reachable_time;
3850	}
3851
 
 
 
 
3852	switch (neigh_parms_family(p)) {
3853	case AF_INET:
3854	      p_name = "ipv4";
3855	      break;
3856	case AF_INET6:
3857	      p_name = "ipv6";
3858	      break;
3859	default:
3860	      BUG();
3861	}
3862
3863	snprintf(neigh_path, sizeof(neigh_path), "net/%s/neigh/%s",
3864		p_name, dev_name_source);
3865	t->sysctl_header =
3866		register_net_sysctl(neigh_parms_net(p), neigh_path, t->neigh_vars);
3867	if (!t->sysctl_header)
3868		goto free;
3869
3870	p->sysctl_table = t;
3871	return 0;
3872
3873free:
3874	kfree(t);
3875err:
3876	return -ENOBUFS;
3877}
3878EXPORT_SYMBOL(neigh_sysctl_register);
3879
3880void neigh_sysctl_unregister(struct neigh_parms *p)
3881{
3882	if (p->sysctl_table) {
3883		struct neigh_sysctl_table *t = p->sysctl_table;
3884		p->sysctl_table = NULL;
3885		unregister_net_sysctl_table(t->sysctl_header);
3886		kfree(t);
3887	}
3888}
3889EXPORT_SYMBOL(neigh_sysctl_unregister);
3890
3891#endif	/* CONFIG_SYSCTL */
3892
3893static int __init neigh_init(void)
3894{
3895	rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL, 0);
3896	rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL, 0);
3897	rtnl_register(PF_UNSPEC, RTM_GETNEIGH, neigh_get, neigh_dump_info, 0);
3898
3899	rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info,
3900		      0);
3901	rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL, 0);
3902
3903	return 0;
3904}
3905
3906subsys_initcall(neigh_init);