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v3.1
 
   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#include <linux/slab.h>
 
  19#include <linux/types.h>
  20#include <linux/kernel.h>
  21#include <linux/module.h>
  22#include <linux/socket.h>
  23#include <linux/netdevice.h>
  24#include <linux/proc_fs.h>
  25#ifdef CONFIG_SYSCTL
  26#include <linux/sysctl.h>
  27#endif
  28#include <linux/times.h>
  29#include <net/net_namespace.h>
  30#include <net/neighbour.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
  40#define NEIGH_DEBUG 1
  41
  42#define NEIGH_PRINTK(x...) printk(x)
  43#define NEIGH_NOPRINTK(x...) do { ; } while(0)
  44#define NEIGH_PRINTK1 NEIGH_NOPRINTK
  45#define NEIGH_PRINTK2 NEIGH_NOPRINTK
  46
  47#if NEIGH_DEBUG >= 1
  48#undef NEIGH_PRINTK1
  49#define NEIGH_PRINTK1 NEIGH_PRINTK
  50#endif
  51#if NEIGH_DEBUG >= 2
  52#undef NEIGH_PRINTK2
  53#define NEIGH_PRINTK2 NEIGH_PRINTK
  54#endif
  55
  56#define PNEIGH_HASHMASK		0xF
  57
  58static void neigh_timer_handler(unsigned long arg);
  59static void __neigh_notify(struct neighbour *n, int type, int flags);
  60static void neigh_update_notify(struct neighbour *neigh);
  61static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
 
 
  62
  63static struct neigh_table *neigh_tables;
  64#ifdef CONFIG_PROC_FS
  65static const struct file_operations neigh_stat_seq_fops;
  66#endif
  67
  68/*
  69   Neighbour hash table buckets are protected with rwlock tbl->lock.
  70
  71   - All the scans/updates to hash buckets MUST be made under this lock.
  72   - NOTHING clever should be made under this lock: no callbacks
  73     to protocol backends, no attempts to send something to network.
  74     It will result in deadlocks, if backend/driver wants to use neighbour
  75     cache.
  76   - If the entry requires some non-trivial actions, increase
  77     its reference count and release table lock.
  78
  79   Neighbour entries are protected:
  80   - with reference count.
  81   - with rwlock neigh->lock
  82
  83   Reference count prevents destruction.
  84
  85   neigh->lock mainly serializes ll address data and its validity state.
  86   However, the same lock is used to protect another entry fields:
  87    - timer
  88    - resolution queue
  89
  90   Again, nothing clever shall be made under neigh->lock,
  91   the most complicated procedure, which we allow is dev->hard_header.
  92   It is supposed, that dev->hard_header is simplistic and does
  93   not make callbacks to neighbour tables.
  94
  95   The last lock is neigh_tbl_lock. It is pure SMP lock, protecting
  96   list of neighbour tables. This list is used only in process context,
  97 */
  98
  99static DEFINE_RWLOCK(neigh_tbl_lock);
 100
 101static int neigh_blackhole(struct neighbour *neigh, struct sk_buff *skb)
 102{
 103	kfree_skb(skb);
 104	return -ENETDOWN;
 105}
 106
 107static void neigh_cleanup_and_release(struct neighbour *neigh)
 108{
 109	if (neigh->parms->neigh_cleanup)
 110		neigh->parms->neigh_cleanup(neigh);
 111
 112	__neigh_notify(neigh, RTM_DELNEIGH, 0);
 113	neigh_release(neigh);
 114}
 115
 116/*
 117 * It is random distribution in the interval (1/2)*base...(3/2)*base.
 118 * It corresponds to default IPv6 settings and is not overridable,
 119 * because it is really reasonable choice.
 120 */
 121
 122unsigned long neigh_rand_reach_time(unsigned long base)
 123{
 124	return base ? (net_random() % base) + (base >> 1) : 0;
 125}
 126EXPORT_SYMBOL(neigh_rand_reach_time);
 127
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 128
 129static int neigh_forced_gc(struct neigh_table *tbl)
 130{
 
 
 
 131	int shrunk = 0;
 132	int i;
 133	struct neigh_hash_table *nht;
 134
 135	NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
 136
 137	write_lock_bh(&tbl->lock);
 138	nht = rcu_dereference_protected(tbl->nht,
 139					lockdep_is_held(&tbl->lock));
 140	for (i = 0; i < (1 << nht->hash_shift); i++) {
 141		struct neighbour *n;
 142		struct neighbour __rcu **np;
 143
 144		np = &nht->hash_buckets[i];
 145		while ((n = rcu_dereference_protected(*np,
 146					lockdep_is_held(&tbl->lock))) != NULL) {
 147			/* Neighbour record may be discarded if:
 148			 * - nobody refers to it.
 149			 * - it is not permanent
 150			 */
 151			write_lock(&n->lock);
 152			if (atomic_read(&n->refcnt) == 1 &&
 153			    !(n->nud_state & NUD_PERMANENT)) {
 154				rcu_assign_pointer(*np,
 155					rcu_dereference_protected(n->next,
 156						  lockdep_is_held(&tbl->lock)));
 157				n->dead = 1;
 158				shrunk	= 1;
 159				write_unlock(&n->lock);
 160				neigh_cleanup_and_release(n);
 161				continue;
 162			}
 163			write_unlock(&n->lock);
 164			np = &n->next;
 
 
 
 
 165		}
 166	}
 167
 168	tbl->last_flush = jiffies;
 169
 170	write_unlock_bh(&tbl->lock);
 171
 172	return shrunk;
 173}
 174
 175static void neigh_add_timer(struct neighbour *n, unsigned long when)
 176{
 
 
 
 
 
 
 177	neigh_hold(n);
 
 
 
 
 178	if (unlikely(mod_timer(&n->timer, when))) {
 179		printk("NEIGH: BUG, double timer add, state is %x\n",
 180		       n->nud_state);
 181		dump_stack();
 182	}
 183}
 184
 185static int neigh_del_timer(struct neighbour *n)
 186{
 187	if ((n->nud_state & NUD_IN_TIMER) &&
 188	    del_timer(&n->timer)) {
 189		neigh_release(n);
 190		return 1;
 191	}
 192	return 0;
 193}
 194
 195static void pneigh_queue_purge(struct sk_buff_head *list)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 196{
 
 
 197	struct sk_buff *skb;
 198
 199	while ((skb = skb_dequeue(list)) != NULL) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 200		dev_put(skb->dev);
 201		kfree_skb(skb);
 202	}
 203}
 204
 205static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev)
 
 206{
 207	int i;
 208	struct neigh_hash_table *nht;
 209
 210	nht = rcu_dereference_protected(tbl->nht,
 211					lockdep_is_held(&tbl->lock));
 212
 213	for (i = 0; i < (1 << nht->hash_shift); i++) {
 214		struct neighbour *n;
 215		struct neighbour __rcu **np = &nht->hash_buckets[i];
 216
 217		while ((n = rcu_dereference_protected(*np,
 218					lockdep_is_held(&tbl->lock))) != NULL) {
 219			if (dev && n->dev != dev) {
 220				np = &n->next;
 221				continue;
 222			}
 
 
 
 
 223			rcu_assign_pointer(*np,
 224				   rcu_dereference_protected(n->next,
 225						lockdep_is_held(&tbl->lock)));
 226			write_lock(&n->lock);
 227			neigh_del_timer(n);
 228			n->dead = 1;
 229
 230			if (atomic_read(&n->refcnt) != 1) {
 231				/* The most unpleasant situation.
 232				   We must destroy neighbour entry,
 233				   but someone still uses it.
 234
 235				   The destroy will be delayed until
 236				   the last user releases us, but
 237				   we must kill timers etc. and move
 238				   it to safe state.
 239				 */
 240				skb_queue_purge(&n->arp_queue);
 
 241				n->output = neigh_blackhole;
 242				if (n->nud_state & NUD_VALID)
 243					n->nud_state = NUD_NOARP;
 244				else
 245					n->nud_state = NUD_NONE;
 246				NEIGH_PRINTK2("neigh %p is stray.\n", n);
 247			}
 248			write_unlock(&n->lock);
 249			neigh_cleanup_and_release(n);
 250		}
 251	}
 252}
 253
 254void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
 255{
 256	write_lock_bh(&tbl->lock);
 257	neigh_flush_dev(tbl, dev);
 258	write_unlock_bh(&tbl->lock);
 259}
 260EXPORT_SYMBOL(neigh_changeaddr);
 261
 262int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
 
 263{
 264	write_lock_bh(&tbl->lock);
 265	neigh_flush_dev(tbl, dev);
 266	pneigh_ifdown(tbl, dev);
 267	write_unlock_bh(&tbl->lock);
 
 
 
 
 
 268
 269	del_timer_sync(&tbl->proxy_timer);
 270	pneigh_queue_purge(&tbl->proxy_queue);
 
 
 
 
 
 
 
 
 271	return 0;
 272}
 273EXPORT_SYMBOL(neigh_ifdown);
 274
 275static struct neighbour *neigh_alloc(struct neigh_table *tbl)
 
 
 276{
 277	struct neighbour *n = NULL;
 278	unsigned long now = jiffies;
 279	int entries;
 280
 281	entries = atomic_inc_return(&tbl->entries) - 1;
 
 
 
 282	if (entries >= tbl->gc_thresh3 ||
 283	    (entries >= tbl->gc_thresh2 &&
 284	     time_after(now, tbl->last_flush + 5 * HZ))) {
 285		if (!neigh_forced_gc(tbl) &&
 286		    entries >= tbl->gc_thresh3)
 
 
 
 287			goto out_entries;
 
 288	}
 289
 290	n = kmem_cache_zalloc(tbl->kmem_cachep, GFP_ATOMIC);
 
 291	if (!n)
 292		goto out_entries;
 293
 294	skb_queue_head_init(&n->arp_queue);
 295	rwlock_init(&n->lock);
 296	seqlock_init(&n->ha_lock);
 297	n->updated	  = n->used = now;
 298	n->nud_state	  = NUD_NONE;
 299	n->output	  = neigh_blackhole;
 
 300	seqlock_init(&n->hh.hh_lock);
 301	n->parms	  = neigh_parms_clone(&tbl->parms);
 302	setup_timer(&n->timer, neigh_timer_handler, (unsigned long)n);
 303
 304	NEIGH_CACHE_STAT_INC(tbl, allocs);
 305	n->tbl		  = tbl;
 306	atomic_set(&n->refcnt, 1);
 307	n->dead		  = 1;
 
 
 
 
 308out:
 309	return n;
 310
 311out_entries:
 312	atomic_dec(&tbl->entries);
 
 313	goto out;
 314}
 315
 
 
 
 
 
 316static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
 317{
 318	size_t size = (1 << shift) * sizeof(struct neighbour *);
 319	struct neigh_hash_table *ret;
 320	struct neighbour __rcu **buckets;
 
 321
 322	ret = kmalloc(sizeof(*ret), GFP_ATOMIC);
 323	if (!ret)
 324		return NULL;
 325	if (size <= PAGE_SIZE)
 326		buckets = kzalloc(size, GFP_ATOMIC);
 327	else
 328		buckets = (struct neighbour __rcu **)
 329			  __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
 330					   get_order(size));
 
 
 331	if (!buckets) {
 332		kfree(ret);
 333		return NULL;
 334	}
 335	ret->hash_buckets = buckets;
 336	ret->hash_shift = shift;
 337	get_random_bytes(&ret->hash_rnd, sizeof(ret->hash_rnd));
 338	ret->hash_rnd |= 1;
 339	return ret;
 340}
 341
 342static void neigh_hash_free_rcu(struct rcu_head *head)
 343{
 344	struct neigh_hash_table *nht = container_of(head,
 345						    struct neigh_hash_table,
 346						    rcu);
 347	size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *);
 348	struct neighbour __rcu **buckets = nht->hash_buckets;
 349
 350	if (size <= PAGE_SIZE)
 351		kfree(buckets);
 352	else
 
 353		free_pages((unsigned long)buckets, get_order(size));
 
 354	kfree(nht);
 355}
 356
 357static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
 358						unsigned long new_shift)
 359{
 360	unsigned int i, hash;
 361	struct neigh_hash_table *new_nht, *old_nht;
 362
 363	NEIGH_CACHE_STAT_INC(tbl, hash_grows);
 364
 365	old_nht = rcu_dereference_protected(tbl->nht,
 366					    lockdep_is_held(&tbl->lock));
 367	new_nht = neigh_hash_alloc(new_shift);
 368	if (!new_nht)
 369		return old_nht;
 370
 371	for (i = 0; i < (1 << old_nht->hash_shift); i++) {
 372		struct neighbour *n, *next;
 373
 374		for (n = rcu_dereference_protected(old_nht->hash_buckets[i],
 375						   lockdep_is_held(&tbl->lock));
 376		     n != NULL;
 377		     n = next) {
 378			hash = tbl->hash(n->primary_key, n->dev,
 379					 new_nht->hash_rnd);
 380
 381			hash >>= (32 - new_nht->hash_shift);
 382			next = rcu_dereference_protected(n->next,
 383						lockdep_is_held(&tbl->lock));
 384
 385			rcu_assign_pointer(n->next,
 386					   rcu_dereference_protected(
 387						new_nht->hash_buckets[hash],
 388						lockdep_is_held(&tbl->lock)));
 389			rcu_assign_pointer(new_nht->hash_buckets[hash], n);
 390		}
 391	}
 392
 393	rcu_assign_pointer(tbl->nht, new_nht);
 394	call_rcu(&old_nht->rcu, neigh_hash_free_rcu);
 395	return new_nht;
 396}
 397
 398struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
 399			       struct net_device *dev)
 400{
 401	struct neighbour *n;
 402	int key_len = tbl->key_len;
 403	u32 hash_val;
 404	struct neigh_hash_table *nht;
 405
 406	NEIGH_CACHE_STAT_INC(tbl, lookups);
 407
 408	rcu_read_lock_bh();
 409	nht = rcu_dereference_bh(tbl->nht);
 410	hash_val = tbl->hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
 411
 412	for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
 413	     n != NULL;
 414	     n = rcu_dereference_bh(n->next)) {
 415		if (dev == n->dev && !memcmp(n->primary_key, pkey, key_len)) {
 416			if (!atomic_inc_not_zero(&n->refcnt))
 417				n = NULL;
 418			NEIGH_CACHE_STAT_INC(tbl, hits);
 419			break;
 420		}
 421	}
 422
 423	rcu_read_unlock_bh();
 424	return n;
 425}
 426EXPORT_SYMBOL(neigh_lookup);
 427
 428struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
 429				     const void *pkey)
 430{
 431	struct neighbour *n;
 432	int key_len = tbl->key_len;
 433	u32 hash_val;
 434	struct neigh_hash_table *nht;
 435
 436	NEIGH_CACHE_STAT_INC(tbl, lookups);
 437
 438	rcu_read_lock_bh();
 439	nht = rcu_dereference_bh(tbl->nht);
 440	hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) >> (32 - nht->hash_shift);
 441
 442	for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
 443	     n != NULL;
 444	     n = rcu_dereference_bh(n->next)) {
 445		if (!memcmp(n->primary_key, pkey, key_len) &&
 446		    net_eq(dev_net(n->dev), net)) {
 447			if (!atomic_inc_not_zero(&n->refcnt))
 448				n = NULL;
 449			NEIGH_CACHE_STAT_INC(tbl, hits);
 450			break;
 451		}
 452	}
 453
 454	rcu_read_unlock_bh();
 455	return n;
 456}
 457EXPORT_SYMBOL(neigh_lookup_nodev);
 458
 459struct neighbour *neigh_create(struct neigh_table *tbl, const void *pkey,
 460			       struct net_device *dev)
 
 
 461{
 462	u32 hash_val;
 463	int key_len = tbl->key_len;
 464	int error;
 465	struct neighbour *n1, *rc, *n = neigh_alloc(tbl);
 466	struct neigh_hash_table *nht;
 
 467
 
 
 468	if (!n) {
 469		rc = ERR_PTR(-ENOBUFS);
 470		goto out;
 471	}
 472
 473	memcpy(n->primary_key, pkey, key_len);
 474	n->dev = dev;
 475	dev_hold(dev);
 476
 477	/* Protocol specific setup. */
 478	if (tbl->constructor &&	(error = tbl->constructor(n)) < 0) {
 479		rc = ERR_PTR(error);
 480		goto out_neigh_release;
 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 - (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			neigh_hold(n1);
 
 513			rc = n1;
 514			goto out_tbl_unlock;
 515		}
 516	}
 517
 518	n->dead = 0;
 519	neigh_hold(n);
 
 
 
 
 
 520	rcu_assign_pointer(n->next,
 521			   rcu_dereference_protected(nht->hash_buckets[hash_val],
 522						     lockdep_is_held(&tbl->lock)));
 523	rcu_assign_pointer(nht->hash_buckets[hash_val], n);
 524	write_unlock_bh(&tbl->lock);
 525	NEIGH_PRINTK2("neigh %p is created.\n", n);
 526	rc = n;
 527out:
 528	return rc;
 529out_tbl_unlock:
 530	write_unlock_bh(&tbl->lock);
 531out_neigh_release:
 
 
 532	neigh_release(n);
 533	goto out;
 534}
 535EXPORT_SYMBOL(neigh_create);
 536
 537static u32 pneigh_hash(const void *pkey, int key_len)
 
 
 
 
 
 
 
 538{
 539	u32 hash_val = *(u32 *)(pkey + key_len - 4);
 540	hash_val ^= (hash_val >> 16);
 541	hash_val ^= hash_val >> 8;
 542	hash_val ^= hash_val >> 4;
 543	hash_val &= PNEIGH_HASHMASK;
 544	return hash_val;
 545}
 546
 547static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n,
 548					      struct net *net,
 549					      const void *pkey,
 550					      int key_len,
 551					      struct net_device *dev)
 552{
 553	while (n) {
 554		if (!memcmp(n->key, pkey, key_len) &&
 555		    net_eq(pneigh_net(n), net) &&
 556		    (n->dev == dev || !n->dev))
 557			return n;
 558		n = n->next;
 559	}
 560	return NULL;
 561}
 562
 563struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
 564		struct net *net, const void *pkey, struct net_device *dev)
 565{
 566	int key_len = tbl->key_len;
 567	u32 hash_val = pneigh_hash(pkey, key_len);
 568
 569	return __pneigh_lookup_1(tbl->phash_buckets[hash_val],
 570				 net, pkey, key_len, dev);
 571}
 572EXPORT_SYMBOL_GPL(__pneigh_lookup);
 573
 574struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
 575				    struct net *net, const void *pkey,
 576				    struct net_device *dev, int creat)
 577{
 578	struct pneigh_entry *n;
 579	int key_len = tbl->key_len;
 580	u32 hash_val = pneigh_hash(pkey, key_len);
 581
 582	read_lock_bh(&tbl->lock);
 583	n = __pneigh_lookup_1(tbl->phash_buckets[hash_val],
 584			      net, pkey, key_len, dev);
 585	read_unlock_bh(&tbl->lock);
 586
 587	if (n || !creat)
 588		goto out;
 589
 590	ASSERT_RTNL();
 591
 592	n = kmalloc(sizeof(*n) + key_len, GFP_KERNEL);
 593	if (!n)
 594		goto out;
 595
 596	write_pnet(&n->net, hold_net(net));
 597	memcpy(n->key, pkey, key_len);
 598	n->dev = dev;
 599	if (dev)
 600		dev_hold(dev);
 601
 602	if (tbl->pconstructor && tbl->pconstructor(n)) {
 603		if (dev)
 604			dev_put(dev);
 605		release_net(net);
 606		kfree(n);
 607		n = NULL;
 608		goto out;
 609	}
 610
 611	write_lock_bh(&tbl->lock);
 612	n->next = tbl->phash_buckets[hash_val];
 613	tbl->phash_buckets[hash_val] = n;
 614	write_unlock_bh(&tbl->lock);
 615out:
 616	return n;
 617}
 618EXPORT_SYMBOL(pneigh_lookup);
 619
 620
 621int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
 622		  struct net_device *dev)
 623{
 624	struct pneigh_entry *n, **np;
 625	int key_len = tbl->key_len;
 626	u32 hash_val = pneigh_hash(pkey, key_len);
 627
 628	write_lock_bh(&tbl->lock);
 629	for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
 630	     np = &n->next) {
 631		if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
 632		    net_eq(pneigh_net(n), net)) {
 633			*np = n->next;
 634			write_unlock_bh(&tbl->lock);
 635			if (tbl->pdestructor)
 636				tbl->pdestructor(n);
 637			if (n->dev)
 638				dev_put(n->dev);
 639			release_net(pneigh_net(n));
 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				release_net(pneigh_net(n));
 663				kfree(n);
 664				continue;
 665			}
 666			np = &n->next;
 667		}
 668	}
 
 
 
 
 
 
 
 
 
 669	return -ENOENT;
 670}
 671
 672static void neigh_parms_destroy(struct neigh_parms *parms);
 673
 674static inline void neigh_parms_put(struct neigh_parms *parms)
 675{
 676	if (atomic_dec_and_test(&parms->refcnt))
 677		neigh_parms_destroy(parms);
 678}
 679
 680static void neigh_destroy_rcu(struct rcu_head *head)
 681{
 682	struct neighbour *neigh = container_of(head, struct neighbour, rcu);
 683
 684	kmem_cache_free(neigh->tbl->kmem_cachep, neigh);
 685}
 686/*
 687 *	neighbour must already be out of the table;
 688 *
 689 */
 690void neigh_destroy(struct neighbour *neigh)
 691{
 
 
 692	NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
 693
 694	if (!neigh->dead) {
 695		printk(KERN_WARNING
 696		       "Destroying alive neighbour %p\n", neigh);
 697		dump_stack();
 698		return;
 699	}
 700
 701	if (neigh_del_timer(neigh))
 702		printk(KERN_WARNING "Impossible event.\n");
 
 
 
 
 
 703
 704	skb_queue_purge(&neigh->arp_queue);
 
 705
 706	dev_put(neigh->dev);
 707	neigh_parms_put(neigh->parms);
 708
 709	NEIGH_PRINTK2("neigh %p is destroyed.\n", neigh);
 710
 711	atomic_dec(&neigh->tbl->entries);
 712	call_rcu(&neigh->rcu, neigh_destroy_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_PRINTK2("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_PRINTK2("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		for (p = &tbl->parms; p; p = p->next)
 762			p->reachable_time =
 763				neigh_rand_reach_time(p->base_reachable_time);
 764	}
 765
 
 
 
 766	for (i = 0 ; i < (1 << nht->hash_shift); i++) {
 767		np = &nht->hash_buckets[i];
 768
 769		while ((n = rcu_dereference_protected(*np,
 770				lockdep_is_held(&tbl->lock))) != NULL) {
 771			unsigned int state;
 772
 773			write_lock(&n->lock);
 774
 775			state = n->nud_state;
 776			if (state & (NUD_PERMANENT | NUD_IN_TIMER)) {
 
 777				write_unlock(&n->lock);
 778				goto next_elt;
 779			}
 780
 781			if (time_before(n->used, n->confirmed))
 
 782				n->used = n->confirmed;
 783
 784			if (atomic_read(&n->refcnt) == 1 &&
 785			    (state == NUD_FAILED ||
 786			     time_after(jiffies, n->used + n->parms->gc_staletime))) {
 
 787				*np = n->next;
 788				n->dead = 1;
 789				write_unlock(&n->lock);
 790				neigh_cleanup_and_release(n);
 791				continue;
 792			}
 793			write_unlock(&n->lock);
 794
 795next_elt:
 796			np = &n->next;
 797		}
 798		/*
 799		 * It's fine to release lock here, even if hash table
 800		 * grows while we are preempted.
 801		 */
 802		write_unlock_bh(&tbl->lock);
 803		cond_resched();
 804		write_lock_bh(&tbl->lock);
 
 
 805	}
 806	/* Cycle through all hash buckets every base_reachable_time/2 ticks.
 807	 * ARP entry timeouts range from 1/2 base_reachable_time to 3/2
 808	 * base_reachable_time.
 
 809	 */
 810	schedule_delayed_work(&tbl->gc_work,
 811			      tbl->parms.base_reachable_time >> 1);
 812	write_unlock_bh(&tbl->lock);
 813}
 814
 815static __inline__ int neigh_max_probes(struct neighbour *n)
 816{
 817	struct neigh_parms *p = n->parms;
 818	return (n->nud_state & NUD_PROBE) ?
 819		p->ucast_probes :
 820		p->ucast_probes + p->app_probes + p->mcast_probes;
 821}
 822
 823static void neigh_invalidate(struct neighbour *neigh)
 824	__releases(neigh->lock)
 825	__acquires(neigh->lock)
 826{
 827	struct sk_buff *skb;
 828
 829	NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
 830	NEIGH_PRINTK2("neigh %p is failed.\n", neigh);
 831	neigh->updated = jiffies;
 832
 833	/* It is very thin place. report_unreachable is very complicated
 834	   routine. Particularly, it can hit the same neighbour entry!
 835
 836	   So that, we try to be accurate and avoid dead loop. --ANK
 837	 */
 838	while (neigh->nud_state == NUD_FAILED &&
 839	       (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
 840		write_unlock(&neigh->lock);
 841		neigh->ops->error_report(neigh, skb);
 842		write_lock(&neigh->lock);
 843	}
 844	skb_queue_purge(&neigh->arp_queue);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 845}
 846
 847/* Called when a timer expires for a neighbour entry. */
 848
 849static void neigh_timer_handler(unsigned long arg)
 850{
 851	unsigned long now, next;
 852	struct neighbour *neigh = (struct neighbour *)arg;
 853	unsigned state;
 854	int notify = 0;
 855
 856	write_lock(&neigh->lock);
 857
 858	state = neigh->nud_state;
 859	now = jiffies;
 860	next = now + HZ;
 861
 862	if (!(state & NUD_IN_TIMER)) {
 863#ifndef CONFIG_SMP
 864		printk(KERN_WARNING "neigh: timer & !nud_in_timer\n");
 865#endif
 866		goto out;
 867	}
 868
 869	if (state & NUD_REACHABLE) {
 870		if (time_before_eq(now,
 871				   neigh->confirmed + neigh->parms->reachable_time)) {
 872			NEIGH_PRINTK2("neigh %p is still alive.\n", neigh);
 873			next = neigh->confirmed + neigh->parms->reachable_time;
 874		} else if (time_before_eq(now,
 875					  neigh->used + neigh->parms->delay_probe_time)) {
 876			NEIGH_PRINTK2("neigh %p is delayed.\n", neigh);
 
 877			neigh->nud_state = NUD_DELAY;
 878			neigh->updated = jiffies;
 879			neigh_suspect(neigh);
 880			next = now + neigh->parms->delay_probe_time;
 881		} else {
 882			NEIGH_PRINTK2("neigh %p is suspected.\n", neigh);
 883			neigh->nud_state = NUD_STALE;
 884			neigh->updated = jiffies;
 885			neigh_suspect(neigh);
 886			notify = 1;
 887		}
 888	} else if (state & NUD_DELAY) {
 889		if (time_before_eq(now,
 890				   neigh->confirmed + neigh->parms->delay_probe_time)) {
 891			NEIGH_PRINTK2("neigh %p is now reachable.\n", neigh);
 
 892			neigh->nud_state = NUD_REACHABLE;
 893			neigh->updated = jiffies;
 894			neigh_connect(neigh);
 895			notify = 1;
 896			next = neigh->confirmed + neigh->parms->reachable_time;
 897		} else {
 898			NEIGH_PRINTK2("neigh %p is probed.\n", neigh);
 899			neigh->nud_state = NUD_PROBE;
 900			neigh->updated = jiffies;
 901			atomic_set(&neigh->probes, 0);
 902			next = now + neigh->parms->retrans_time;
 
 
 903		}
 904	} else {
 905		/* NUD_PROBE|NUD_INCOMPLETE */
 906		next = now + neigh->parms->retrans_time;
 907	}
 908
 909	if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
 910	    atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
 911		neigh->nud_state = NUD_FAILED;
 912		notify = 1;
 913		neigh_invalidate(neigh);
 
 914	}
 915
 916	if (neigh->nud_state & NUD_IN_TIMER) {
 917		if (time_before(next, jiffies + HZ/2))
 918			next = jiffies + HZ/2;
 919		if (!mod_timer(&neigh->timer, next))
 920			neigh_hold(neigh);
 921	}
 922	if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
 923		struct sk_buff *skb = skb_peek(&neigh->arp_queue);
 924		/* keep skb alive even if arp_queue overflows */
 925		if (skb)
 926			skb = skb_copy(skb, GFP_ATOMIC);
 927		write_unlock(&neigh->lock);
 928		neigh->ops->solicit(neigh, skb);
 929		atomic_inc(&neigh->probes);
 930		kfree_skb(skb);
 931	} else {
 932out:
 933		write_unlock(&neigh->lock);
 934	}
 935
 936	if (notify)
 937		neigh_update_notify(neigh);
 
 
 938
 939	neigh_release(neigh);
 940}
 941
 942int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
 
 943{
 944	int rc;
 945	unsigned long now;
 946
 947	write_lock_bh(&neigh->lock);
 948
 949	rc = 0;
 950	if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
 951		goto out_unlock_bh;
 952
 953	now = jiffies;
 954
 955	if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
 956		if (neigh->parms->mcast_probes + neigh->parms->app_probes) {
 957			atomic_set(&neigh->probes, neigh->parms->ucast_probes);
 958			neigh->nud_state     = NUD_INCOMPLETE;
 959			neigh->updated = jiffies;
 960			neigh_add_timer(neigh, now + 1);
 
 
 
 
 
 
 
 
 
 
 
 
 
 961		} else {
 962			neigh->nud_state = NUD_FAILED;
 963			neigh->updated = jiffies;
 964			write_unlock_bh(&neigh->lock);
 965
 966			kfree_skb(skb);
 967			return 1;
 968		}
 969	} else if (neigh->nud_state & NUD_STALE) {
 970		NEIGH_PRINTK2("neigh %p is delayed.\n", neigh);
 
 971		neigh->nud_state = NUD_DELAY;
 972		neigh->updated = jiffies;
 973		neigh_add_timer(neigh,
 974				jiffies + neigh->parms->delay_probe_time);
 975	}
 976
 977	if (neigh->nud_state == NUD_INCOMPLETE) {
 978		if (skb) {
 979			if (skb_queue_len(&neigh->arp_queue) >=
 980			    neigh->parms->queue_len) {
 981				struct sk_buff *buff;
 
 982				buff = __skb_dequeue(&neigh->arp_queue);
 983				kfree_skb(buff);
 
 
 
 984				NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
 985			}
 986			skb_dst_force(skb);
 987			__skb_queue_tail(&neigh->arp_queue, skb);
 
 988		}
 989		rc = 1;
 990	}
 991out_unlock_bh:
 992	write_unlock_bh(&neigh->lock);
 
 
 
 
 
 993	return rc;
 
 
 
 
 
 
 
 
 994}
 995EXPORT_SYMBOL(__neigh_event_send);
 996
 997static void neigh_update_hhs(struct neighbour *neigh)
 998{
 999	struct hh_cache *hh;
1000	void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
1001		= NULL;
1002
1003	if (neigh->dev->header_ops)
1004		update = neigh->dev->header_ops->cache_update;
1005
1006	if (update) {
1007		hh = &neigh->hh;
1008		if (hh->hh_len) {
1009			write_seqlock_bh(&hh->hh_lock);
1010			update(hh, neigh->dev, neigh->ha);
1011			write_sequnlock_bh(&hh->hh_lock);
1012		}
1013	}
1014}
1015
1016
1017
1018/* Generic update routine.
1019   -- lladdr is new lladdr or NULL, if it is not supplied.
1020   -- new    is new state.
1021   -- flags
1022	NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
1023				if it is different.
1024	NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
1025				lladdr instead of overriding it
1026				if it is different.
1027				It also allows to retain current state
1028				if lladdr is unchanged.
1029	NEIGH_UPDATE_F_ADMIN	means that the change is administrative.
1030
 
1031	NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
1032				NTF_ROUTER flag.
1033	NEIGH_UPDATE_F_ISROUTER	indicates if the neighbour is known as
1034				a router.
1035
1036   Caller MUST hold reference count on the entry.
1037 */
1038
1039int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
1040		 u32 flags)
1041{
1042	u8 old;
1043	int err;
1044	int notify = 0;
1045	struct net_device *dev;
1046	int update_isrouter = 0;
 
 
 
 
 
1047
1048	write_lock_bh(&neigh->lock);
1049
1050	dev    = neigh->dev;
1051	old    = neigh->nud_state;
1052	err    = -EPERM;
1053
 
 
 
 
 
1054	if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
1055	    (old & (NUD_NOARP | NUD_PERMANENT)))
1056		goto out;
1057
 
 
 
 
 
 
 
 
1058	if (!(new & NUD_VALID)) {
1059		neigh_del_timer(neigh);
1060		if (old & NUD_CONNECTED)
1061			neigh_suspect(neigh);
1062		neigh->nud_state = new;
1063		err = 0;
1064		notify = old & NUD_VALID;
1065		if ((old & (NUD_INCOMPLETE | NUD_PROBE)) &&
1066		    (new & NUD_FAILED)) {
1067			neigh_invalidate(neigh);
1068			notify = 1;
1069		}
1070		goto out;
1071	}
1072
1073	/* Compare new lladdr with cached one */
1074	if (!dev->addr_len) {
1075		/* First case: device needs no address. */
1076		lladdr = neigh->ha;
1077	} else if (lladdr) {
1078		/* The second case: if something is already cached
1079		   and a new address is proposed:
1080		   - compare new & old
1081		   - if they are different, check override flag
1082		 */
1083		if ((old & NUD_VALID) &&
1084		    !memcmp(lladdr, neigh->ha, dev->addr_len))
1085			lladdr = neigh->ha;
1086	} else {
1087		/* No address is supplied; if we know something,
1088		   use it, otherwise discard the request.
1089		 */
1090		err = -EINVAL;
1091		if (!(old & NUD_VALID))
 
1092			goto out;
 
1093		lladdr = neigh->ha;
1094	}
1095
 
 
 
1096	if (new & NUD_CONNECTED)
1097		neigh->confirmed = jiffies;
1098	neigh->updated = jiffies;
1099
1100	/* If entry was valid and address is not changed,
1101	   do not change entry state, if new one is STALE.
1102	 */
1103	err = 0;
1104	update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1105	if (old & NUD_VALID) {
1106		if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
1107			update_isrouter = 0;
1108			if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
1109			    (old & NUD_CONNECTED)) {
1110				lladdr = neigh->ha;
1111				new = NUD_STALE;
1112			} else
1113				goto out;
1114		} else {
1115			if (lladdr == neigh->ha && new == NUD_STALE &&
1116			    ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) ||
1117			     (old & NUD_CONNECTED))
1118			    )
1119				new = old;
1120		}
1121	}
1122
 
 
 
 
 
 
 
1123	if (new != old) {
1124		neigh_del_timer(neigh);
 
 
1125		if (new & NUD_IN_TIMER)
1126			neigh_add_timer(neigh, (jiffies +
1127						((new & NUD_REACHABLE) ?
1128						 neigh->parms->reachable_time :
1129						 0)));
1130		neigh->nud_state = new;
 
1131	}
1132
1133	if (lladdr != neigh->ha) {
1134		write_seqlock(&neigh->ha_lock);
1135		memcpy(&neigh->ha, lladdr, dev->addr_len);
1136		write_sequnlock(&neigh->ha_lock);
1137		neigh_update_hhs(neigh);
1138		if (!(new & NUD_CONNECTED))
1139			neigh->confirmed = jiffies -
1140				      (neigh->parms->base_reachable_time << 1);
1141		notify = 1;
1142	}
1143	if (new == old)
1144		goto out;
1145	if (new & NUD_CONNECTED)
1146		neigh_connect(neigh);
1147	else
1148		neigh_suspect(neigh);
1149	if (!(old & NUD_VALID)) {
1150		struct sk_buff *skb;
1151
1152		/* Again: avoid dead loop if something went wrong */
1153
1154		while (neigh->nud_state & NUD_VALID &&
1155		       (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1156			struct dst_entry *dst = skb_dst(skb);
1157			struct neighbour *n2, *n1 = neigh;
1158			write_unlock_bh(&neigh->lock);
1159			/* On shaper/eql skb->dst->neighbour != neigh :( */
1160			if (dst && (n2 = dst_get_neighbour(dst)) != NULL)
1161				n1 = n2;
 
 
 
 
 
 
 
 
 
 
 
 
 
1162			n1->output(n1, skb);
 
 
 
 
1163			write_lock_bh(&neigh->lock);
1164		}
1165		skb_queue_purge(&neigh->arp_queue);
 
1166	}
1167out:
1168	if (update_isrouter) {
1169		neigh->flags = (flags & NEIGH_UPDATE_F_ISROUTER) ?
1170			(neigh->flags | NTF_ROUTER) :
1171			(neigh->flags & ~NTF_ROUTER);
1172	}
1173	write_unlock_bh(&neigh->lock);
1174
 
 
 
1175	if (notify)
1176		neigh_update_notify(neigh);
1177
1178	return err;
1179}
 
 
 
 
 
 
1180EXPORT_SYMBOL(neigh_update);
1181
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1182struct neighbour *neigh_event_ns(struct neigh_table *tbl,
1183				 u8 *lladdr, void *saddr,
1184				 struct net_device *dev)
1185{
1186	struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev,
1187						 lladdr || !dev->addr_len);
1188	if (neigh)
1189		neigh_update(neigh, lladdr, NUD_STALE,
1190			     NEIGH_UPDATE_F_OVERRIDE);
1191	return neigh;
1192}
1193EXPORT_SYMBOL(neigh_event_ns);
1194
1195/* called with read_lock_bh(&n->lock); */
1196static void neigh_hh_init(struct neighbour *n, struct dst_entry *dst)
1197{
1198	struct net_device *dev = dst->dev;
1199	__be16 prot = dst->ops->protocol;
1200	struct hh_cache	*hh = &n->hh;
1201
1202	write_lock_bh(&n->lock);
1203
1204	/* Only one thread can come in here and initialize the
1205	 * hh_cache entry.
1206	 */
1207	if (!hh->hh_len)
1208		dev->header_ops->cache(n, hh, prot);
1209
1210	write_unlock_bh(&n->lock);
1211}
1212
1213/* This function can be used in contexts, where only old dev_queue_xmit
1214 * worked, f.e. if you want to override normal output path (eql, shaper),
1215 * but resolution is not made yet.
1216 */
1217
1218int neigh_compat_output(struct neighbour *neigh, struct sk_buff *skb)
1219{
1220	struct net_device *dev = skb->dev;
1221
1222	__skb_pull(skb, skb_network_offset(skb));
1223
1224	if (dev_hard_header(skb, dev, ntohs(skb->protocol), NULL, NULL,
1225			    skb->len) < 0 &&
1226	    dev->header_ops->rebuild(skb))
1227		return 0;
1228
1229	return dev_queue_xmit(skb);
1230}
1231EXPORT_SYMBOL(neigh_compat_output);
1232
1233/* Slow and careful. */
1234
1235int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb)
1236{
1237	struct dst_entry *dst = skb_dst(skb);
1238	int rc = 0;
1239
1240	if (!dst)
1241		goto discard;
1242
1243	__skb_pull(skb, skb_network_offset(skb));
1244
1245	if (!neigh_event_send(neigh, skb)) {
1246		int err;
1247		struct net_device *dev = neigh->dev;
1248		unsigned int seq;
1249
1250		if (dev->header_ops->cache && !neigh->hh.hh_len)
1251			neigh_hh_init(neigh, dst);
1252
1253		do {
 
1254			seq = read_seqbegin(&neigh->ha_lock);
1255			err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1256					      neigh->ha, NULL, skb->len);
1257		} while (read_seqretry(&neigh->ha_lock, seq));
1258
1259		if (err >= 0)
1260			rc = dev_queue_xmit(skb);
1261		else
1262			goto out_kfree_skb;
1263	}
1264out:
1265	return rc;
1266discard:
1267	NEIGH_PRINTK1("neigh_resolve_output: dst=%p neigh=%p\n",
1268		      dst, neigh);
1269out_kfree_skb:
1270	rc = -EINVAL;
1271	kfree_skb(skb);
1272	goto out;
1273}
1274EXPORT_SYMBOL(neigh_resolve_output);
1275
1276/* As fast as possible without hh cache */
1277
1278int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb)
1279{
1280	struct net_device *dev = neigh->dev;
1281	unsigned int seq;
1282	int err;
1283
1284	__skb_pull(skb, skb_network_offset(skb));
1285
1286	do {
 
1287		seq = read_seqbegin(&neigh->ha_lock);
1288		err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1289				      neigh->ha, NULL, skb->len);
1290	} while (read_seqretry(&neigh->ha_lock, seq));
1291
1292	if (err >= 0)
1293		err = dev_queue_xmit(skb);
1294	else {
1295		err = -EINVAL;
1296		kfree_skb(skb);
1297	}
1298	return err;
1299}
1300EXPORT_SYMBOL(neigh_connected_output);
1301
1302int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb)
1303{
1304	return dev_queue_xmit(skb);
1305}
1306EXPORT_SYMBOL(neigh_direct_output);
1307
1308static void neigh_proxy_process(unsigned long arg)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1309{
1310	struct neigh_table *tbl = (struct neigh_table *)arg;
1311	long sched_next = 0;
1312	unsigned long now = jiffies;
1313	struct sk_buff *skb, *n;
1314
1315	spin_lock(&tbl->proxy_queue.lock);
1316
1317	skb_queue_walk_safe(&tbl->proxy_queue, skb, n) {
1318		long tdif = NEIGH_CB(skb)->sched_next - now;
1319
1320		if (tdif <= 0) {
1321			struct net_device *dev = skb->dev;
1322
 
1323			__skb_unlink(skb, &tbl->proxy_queue);
 
1324			if (tbl->proxy_redo && netif_running(dev)) {
1325				rcu_read_lock();
1326				tbl->proxy_redo(skb);
1327				rcu_read_unlock();
1328			} else {
1329				kfree_skb(skb);
1330			}
1331
1332			dev_put(dev);
1333		} else if (!sched_next || tdif < sched_next)
1334			sched_next = tdif;
1335	}
1336	del_timer(&tbl->proxy_timer);
1337	if (sched_next)
1338		mod_timer(&tbl->proxy_timer, jiffies + sched_next);
1339	spin_unlock(&tbl->proxy_queue.lock);
1340}
1341
1342void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
1343		    struct sk_buff *skb)
1344{
1345	unsigned long now = jiffies;
1346	unsigned long sched_next = now + (net_random() % p->proxy_delay);
1347
1348	if (tbl->proxy_queue.qlen > p->proxy_qlen) {
1349		kfree_skb(skb);
1350		return;
1351	}
1352
1353	NEIGH_CB(skb)->sched_next = sched_next;
1354	NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
1355
1356	spin_lock(&tbl->proxy_queue.lock);
1357	if (del_timer(&tbl->proxy_timer)) {
1358		if (time_before(tbl->proxy_timer.expires, sched_next))
1359			sched_next = tbl->proxy_timer.expires;
1360	}
1361	skb_dst_drop(skb);
1362	dev_hold(skb->dev);
1363	__skb_queue_tail(&tbl->proxy_queue, skb);
 
1364	mod_timer(&tbl->proxy_timer, sched_next);
1365	spin_unlock(&tbl->proxy_queue.lock);
1366}
1367EXPORT_SYMBOL(pneigh_enqueue);
1368
1369static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl,
1370						      struct net *net, int ifindex)
1371{
1372	struct neigh_parms *p;
1373
1374	for (p = &tbl->parms; p; p = p->next) {
1375		if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
1376		    (!p->dev && !ifindex))
1377			return p;
1378	}
1379
1380	return NULL;
1381}
1382
1383struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
1384				      struct neigh_table *tbl)
1385{
1386	struct neigh_parms *p, *ref;
1387	struct net *net = dev_net(dev);
1388	const struct net_device_ops *ops = dev->netdev_ops;
1389
1390	ref = lookup_neigh_parms(tbl, net, 0);
1391	if (!ref)
1392		return NULL;
1393
1394	p = kmemdup(ref, sizeof(*p), GFP_KERNEL);
1395	if (p) {
1396		p->tbl		  = tbl;
1397		atomic_set(&p->refcnt, 1);
1398		p->reachable_time =
1399				neigh_rand_reach_time(p->base_reachable_time);
 
 
 
 
 
1400
1401		if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) {
 
1402			kfree(p);
1403			return NULL;
1404		}
1405
1406		dev_hold(dev);
1407		p->dev = dev;
1408		write_pnet(&p->net, hold_net(net));
1409		p->sysctl_table = NULL;
1410		write_lock_bh(&tbl->lock);
1411		p->next		= tbl->parms.next;
1412		tbl->parms.next = p;
1413		write_unlock_bh(&tbl->lock);
 
 
1414	}
1415	return p;
1416}
1417EXPORT_SYMBOL(neigh_parms_alloc);
1418
1419static void neigh_rcu_free_parms(struct rcu_head *head)
1420{
1421	struct neigh_parms *parms =
1422		container_of(head, struct neigh_parms, rcu_head);
1423
1424	neigh_parms_put(parms);
1425}
1426
1427void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
1428{
1429	struct neigh_parms **p;
1430
1431	if (!parms || parms == &tbl->parms)
1432		return;
1433	write_lock_bh(&tbl->lock);
1434	for (p = &tbl->parms.next; *p; p = &(*p)->next) {
1435		if (*p == parms) {
1436			*p = parms->next;
1437			parms->dead = 1;
1438			write_unlock_bh(&tbl->lock);
1439			if (parms->dev)
1440				dev_put(parms->dev);
1441			call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
1442			return;
1443		}
1444	}
1445	write_unlock_bh(&tbl->lock);
1446	NEIGH_PRINTK1("neigh_parms_release: not found\n");
 
1447}
1448EXPORT_SYMBOL(neigh_parms_release);
1449
1450static void neigh_parms_destroy(struct neigh_parms *parms)
1451{
1452	release_net(neigh_parms_net(parms));
1453	kfree(parms);
1454}
1455
1456static struct lock_class_key neigh_table_proxy_queue_class;
1457
1458void neigh_table_init_no_netlink(struct neigh_table *tbl)
 
 
1459{
1460	unsigned long now = jiffies;
1461	unsigned long phsize;
1462
 
 
 
 
 
1463	write_pnet(&tbl->parms.net, &init_net);
1464	atomic_set(&tbl->parms.refcnt, 1);
1465	tbl->parms.reachable_time =
1466			  neigh_rand_reach_time(tbl->parms.base_reachable_time);
 
1467
1468	if (!tbl->kmem_cachep)
1469		tbl->kmem_cachep =
1470			kmem_cache_create(tbl->id, tbl->entry_size, 0,
1471					  SLAB_HWCACHE_ALIGN|SLAB_PANIC,
1472					  NULL);
1473	tbl->stats = alloc_percpu(struct neigh_statistics);
1474	if (!tbl->stats)
1475		panic("cannot create neighbour cache statistics");
1476
1477#ifdef CONFIG_PROC_FS
1478	if (!proc_create_data(tbl->id, 0, init_net.proc_net_stat,
1479			      &neigh_stat_seq_fops, tbl))
1480		panic("cannot create neighbour proc dir entry");
1481#endif
1482
1483	RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3));
1484
1485	phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
1486	tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
1487
1488	if (!tbl->nht || !tbl->phash_buckets)
1489		panic("cannot allocate neighbour cache hashes");
1490
 
 
 
 
 
 
1491	rwlock_init(&tbl->lock);
1492	INIT_DELAYED_WORK_DEFERRABLE(&tbl->gc_work, neigh_periodic_work);
1493	schedule_delayed_work(&tbl->gc_work, tbl->parms.reachable_time);
1494	setup_timer(&tbl->proxy_timer, neigh_proxy_process, (unsigned long)tbl);
 
 
 
 
 
1495	skb_queue_head_init_class(&tbl->proxy_queue,
1496			&neigh_table_proxy_queue_class);
1497
1498	tbl->last_flush = now;
1499	tbl->last_rand	= now + tbl->parms.reachable_time * 20;
1500}
1501EXPORT_SYMBOL(neigh_table_init_no_netlink);
1502
1503void neigh_table_init(struct neigh_table *tbl)
1504{
1505	struct neigh_table *tmp;
1506
1507	neigh_table_init_no_netlink(tbl);
1508	write_lock(&neigh_tbl_lock);
1509	for (tmp = neigh_tables; tmp; tmp = tmp->next) {
1510		if (tmp->family == tbl->family)
1511			break;
1512	}
1513	tbl->next	= neigh_tables;
1514	neigh_tables	= tbl;
1515	write_unlock(&neigh_tbl_lock);
1516
1517	if (unlikely(tmp)) {
1518		printk(KERN_ERR "NEIGH: Registering multiple tables for "
1519		       "family %d\n", tbl->family);
1520		dump_stack();
1521	}
1522}
1523EXPORT_SYMBOL(neigh_table_init);
1524
1525int neigh_table_clear(struct neigh_table *tbl)
1526{
1527	struct neigh_table **tp;
1528
1529	/* It is not clean... Fix it to unload IPv6 module safely */
 
1530	cancel_delayed_work_sync(&tbl->gc_work);
1531	del_timer_sync(&tbl->proxy_timer);
1532	pneigh_queue_purge(&tbl->proxy_queue);
1533	neigh_ifdown(tbl, NULL);
1534	if (atomic_read(&tbl->entries))
1535		printk(KERN_CRIT "neighbour leakage\n");
1536	write_lock(&neigh_tbl_lock);
1537	for (tp = &neigh_tables; *tp; tp = &(*tp)->next) {
1538		if (*tp == tbl) {
1539			*tp = tbl->next;
1540			break;
1541		}
1542	}
1543	write_unlock(&neigh_tbl_lock);
1544
1545	call_rcu(&rcu_dereference_protected(tbl->nht, 1)->rcu,
1546		 neigh_hash_free_rcu);
1547	tbl->nht = NULL;
1548
1549	kfree(tbl->phash_buckets);
1550	tbl->phash_buckets = NULL;
1551
1552	remove_proc_entry(tbl->id, init_net.proc_net_stat);
1553
1554	free_percpu(tbl->stats);
1555	tbl->stats = NULL;
1556
1557	kmem_cache_destroy(tbl->kmem_cachep);
1558	tbl->kmem_cachep = NULL;
1559
1560	return 0;
1561}
1562EXPORT_SYMBOL(neigh_table_clear);
1563
1564static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1565{
1566	struct net *net = sock_net(skb->sk);
1567	struct ndmsg *ndm;
1568	struct nlattr *dst_attr;
1569	struct neigh_table *tbl;
 
1570	struct net_device *dev = NULL;
1571	int err = -EINVAL;
1572
1573	ASSERT_RTNL();
1574	if (nlmsg_len(nlh) < sizeof(*ndm))
1575		goto out;
1576
1577	dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
1578	if (dst_attr == NULL)
 
1579		goto out;
 
1580
1581	ndm = nlmsg_data(nlh);
1582	if (ndm->ndm_ifindex) {
1583		dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1584		if (dev == NULL) {
1585			err = -ENODEV;
1586			goto out;
1587		}
1588	}
1589
1590	read_lock(&neigh_tbl_lock);
1591	for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1592		struct neighbour *neigh;
1593
1594		if (tbl->family != ndm->ndm_family)
1595			continue;
1596		read_unlock(&neigh_tbl_lock);
1597
1598		if (nla_len(dst_attr) < tbl->key_len)
1599			goto out;
1600
1601		if (ndm->ndm_flags & NTF_PROXY) {
1602			err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
1603			goto out;
1604		}
1605
1606		if (dev == NULL)
1607			goto out;
 
 
1608
1609		neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
1610		if (neigh == NULL) {
1611			err = -ENOENT;
1612			goto out;
1613		}
1614
1615		err = neigh_update(neigh, NULL, NUD_FAILED,
1616				   NEIGH_UPDATE_F_OVERRIDE |
1617				   NEIGH_UPDATE_F_ADMIN);
1618		neigh_release(neigh);
1619		goto out;
1620	}
1621	read_unlock(&neigh_tbl_lock);
1622	err = -EAFNOSUPPORT;
 
 
 
 
 
 
1623
1624out:
1625	return err;
1626}
1627
1628static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 
1629{
 
 
1630	struct net *net = sock_net(skb->sk);
1631	struct ndmsg *ndm;
1632	struct nlattr *tb[NDA_MAX+1];
1633	struct neigh_table *tbl;
1634	struct net_device *dev = NULL;
 
 
 
 
1635	int err;
1636
1637	ASSERT_RTNL();
1638	err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, NULL);
 
1639	if (err < 0)
1640		goto out;
1641
1642	err = -EINVAL;
1643	if (tb[NDA_DST] == NULL)
 
1644		goto out;
 
1645
1646	ndm = nlmsg_data(nlh);
 
 
 
 
 
 
 
 
 
1647	if (ndm->ndm_ifindex) {
1648		dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1649		if (dev == NULL) {
1650			err = -ENODEV;
1651			goto out;
1652		}
1653
1654		if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len)
 
1655			goto out;
 
1656	}
1657
1658	read_lock(&neigh_tbl_lock);
1659	for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1660		int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE;
1661		struct neighbour *neigh;
1662		void *dst, *lladdr;
1663
1664		if (tbl->family != ndm->ndm_family)
1665			continue;
1666		read_unlock(&neigh_tbl_lock);
 
1667
1668		if (nla_len(tb[NDA_DST]) < tbl->key_len)
1669			goto out;
1670		dst = nla_data(tb[NDA_DST]);
1671		lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
1672
1673		if (ndm->ndm_flags & NTF_PROXY) {
1674			struct pneigh_entry *pn;
 
 
1675
1676			err = -ENOBUFS;
1677			pn = pneigh_lookup(tbl, net, dst, dev, 1);
1678			if (pn) {
1679				pn->flags = ndm->ndm_flags;
1680				err = 0;
1681			}
1682			goto out;
1683		}
1684
1685		if (dev == NULL)
1686			goto out;
 
 
 
 
 
 
 
 
1687
1688		neigh = neigh_lookup(tbl, dst, dev);
1689		if (neigh == NULL) {
1690			if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
1691				err = -ENOENT;
1692				goto out;
1693			}
1694
1695			neigh = __neigh_lookup_errno(tbl, dst, dev);
1696			if (IS_ERR(neigh)) {
1697				err = PTR_ERR(neigh);
1698				goto out;
1699			}
1700		} else {
1701			if (nlh->nlmsg_flags & NLM_F_EXCL) {
1702				err = -EEXIST;
1703				neigh_release(neigh);
1704				goto out;
1705			}
1706
1707			if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
1708				flags &= ~NEIGH_UPDATE_F_OVERRIDE;
 
 
 
 
 
 
 
 
 
 
 
 
1709		}
1710
1711		if (ndm->ndm_flags & NTF_USE) {
1712			neigh_event_send(neigh, NULL);
1713			err = 0;
1714		} else
1715			err = neigh_update(neigh, lladdr, ndm->ndm_state, flags);
1716		neigh_release(neigh);
1717		goto out;
1718	}
 
 
 
 
 
 
1719
1720	read_unlock(&neigh_tbl_lock);
1721	err = -EAFNOSUPPORT;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1722out:
1723	return err;
1724}
1725
1726static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
1727{
1728	struct nlattr *nest;
1729
1730	nest = nla_nest_start(skb, NDTA_PARMS);
1731	if (nest == NULL)
1732		return -ENOBUFS;
1733
1734	if (parms->dev)
1735		NLA_PUT_U32(skb, NDTPA_IFINDEX, parms->dev->ifindex);
1736
1737	NLA_PUT_U32(skb, NDTPA_REFCNT, atomic_read(&parms->refcnt));
1738	NLA_PUT_U32(skb, NDTPA_QUEUE_LEN, parms->queue_len);
1739	NLA_PUT_U32(skb, NDTPA_PROXY_QLEN, parms->proxy_qlen);
1740	NLA_PUT_U32(skb, NDTPA_APP_PROBES, parms->app_probes);
1741	NLA_PUT_U32(skb, NDTPA_UCAST_PROBES, parms->ucast_probes);
1742	NLA_PUT_U32(skb, NDTPA_MCAST_PROBES, parms->mcast_probes);
1743	NLA_PUT_MSECS(skb, NDTPA_REACHABLE_TIME, parms->reachable_time);
1744	NLA_PUT_MSECS(skb, NDTPA_BASE_REACHABLE_TIME,
1745		      parms->base_reachable_time);
1746	NLA_PUT_MSECS(skb, NDTPA_GC_STALETIME, parms->gc_staletime);
1747	NLA_PUT_MSECS(skb, NDTPA_DELAY_PROBE_TIME, parms->delay_probe_time);
1748	NLA_PUT_MSECS(skb, NDTPA_RETRANS_TIME, parms->retrans_time);
1749	NLA_PUT_MSECS(skb, NDTPA_ANYCAST_DELAY, parms->anycast_delay);
1750	NLA_PUT_MSECS(skb, NDTPA_PROXY_DELAY, parms->proxy_delay);
1751	NLA_PUT_MSECS(skb, NDTPA_LOCKTIME, parms->locktime);
1752
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1753	return nla_nest_end(skb, nest);
1754
1755nla_put_failure:
1756	nla_nest_cancel(skb, nest);
1757	return -EMSGSIZE;
1758}
1759
1760static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
1761			      u32 pid, u32 seq, int type, int flags)
1762{
1763	struct nlmsghdr *nlh;
1764	struct ndtmsg *ndtmsg;
1765
1766	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1767	if (nlh == NULL)
1768		return -EMSGSIZE;
1769
1770	ndtmsg = nlmsg_data(nlh);
1771
1772	read_lock_bh(&tbl->lock);
1773	ndtmsg->ndtm_family = tbl->family;
1774	ndtmsg->ndtm_pad1   = 0;
1775	ndtmsg->ndtm_pad2   = 0;
1776
1777	NLA_PUT_STRING(skb, NDTA_NAME, tbl->id);
1778	NLA_PUT_MSECS(skb, NDTA_GC_INTERVAL, tbl->gc_interval);
1779	NLA_PUT_U32(skb, NDTA_THRESH1, tbl->gc_thresh1);
1780	NLA_PUT_U32(skb, NDTA_THRESH2, tbl->gc_thresh2);
1781	NLA_PUT_U32(skb, NDTA_THRESH3, tbl->gc_thresh3);
1782
1783	{
1784		unsigned long now = jiffies;
1785		unsigned int flush_delta = now - tbl->last_flush;
1786		unsigned int rand_delta = now - tbl->last_rand;
1787		struct neigh_hash_table *nht;
1788		struct ndt_config ndc = {
1789			.ndtc_key_len		= tbl->key_len,
1790			.ndtc_entry_size	= tbl->entry_size,
1791			.ndtc_entries		= atomic_read(&tbl->entries),
1792			.ndtc_last_flush	= jiffies_to_msecs(flush_delta),
1793			.ndtc_last_rand		= jiffies_to_msecs(rand_delta),
1794			.ndtc_proxy_qlen	= tbl->proxy_queue.qlen,
1795		};
1796
1797		rcu_read_lock_bh();
1798		nht = rcu_dereference_bh(tbl->nht);
1799		ndc.ndtc_hash_rnd = nht->hash_rnd;
1800		ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
1801		rcu_read_unlock_bh();
1802
1803		NLA_PUT(skb, NDTA_CONFIG, sizeof(ndc), &ndc);
 
1804	}
1805
1806	{
1807		int cpu;
1808		struct ndt_stats ndst;
1809
1810		memset(&ndst, 0, sizeof(ndst));
1811
1812		for_each_possible_cpu(cpu) {
1813			struct neigh_statistics	*st;
1814
1815			st = per_cpu_ptr(tbl->stats, cpu);
1816			ndst.ndts_allocs		+= st->allocs;
1817			ndst.ndts_destroys		+= st->destroys;
1818			ndst.ndts_hash_grows		+= st->hash_grows;
1819			ndst.ndts_res_failed		+= st->res_failed;
1820			ndst.ndts_lookups		+= st->lookups;
1821			ndst.ndts_hits			+= st->hits;
1822			ndst.ndts_rcv_probes_mcast	+= st->rcv_probes_mcast;
1823			ndst.ndts_rcv_probes_ucast	+= st->rcv_probes_ucast;
1824			ndst.ndts_periodic_gc_runs	+= st->periodic_gc_runs;
1825			ndst.ndts_forced_gc_runs	+= st->forced_gc_runs;
 
1826		}
1827
1828		NLA_PUT(skb, NDTA_STATS, sizeof(ndst), &ndst);
 
 
1829	}
1830
1831	BUG_ON(tbl->parms.dev);
1832	if (neightbl_fill_parms(skb, &tbl->parms) < 0)
1833		goto nla_put_failure;
1834
1835	read_unlock_bh(&tbl->lock);
1836	return nlmsg_end(skb, nlh);
 
1837
1838nla_put_failure:
1839	read_unlock_bh(&tbl->lock);
1840	nlmsg_cancel(skb, nlh);
1841	return -EMSGSIZE;
1842}
1843
1844static int neightbl_fill_param_info(struct sk_buff *skb,
1845				    struct neigh_table *tbl,
1846				    struct neigh_parms *parms,
1847				    u32 pid, u32 seq, int type,
1848				    unsigned int flags)
1849{
1850	struct ndtmsg *ndtmsg;
1851	struct nlmsghdr *nlh;
1852
1853	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
1854	if (nlh == NULL)
1855		return -EMSGSIZE;
1856
1857	ndtmsg = nlmsg_data(nlh);
1858
1859	read_lock_bh(&tbl->lock);
1860	ndtmsg->ndtm_family = tbl->family;
1861	ndtmsg->ndtm_pad1   = 0;
1862	ndtmsg->ndtm_pad2   = 0;
1863
1864	if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
1865	    neightbl_fill_parms(skb, parms) < 0)
1866		goto errout;
1867
1868	read_unlock_bh(&tbl->lock);
1869	return nlmsg_end(skb, nlh);
 
1870errout:
1871	read_unlock_bh(&tbl->lock);
1872	nlmsg_cancel(skb, nlh);
1873	return -EMSGSIZE;
1874}
1875
1876static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
1877	[NDTA_NAME]		= { .type = NLA_STRING },
1878	[NDTA_THRESH1]		= { .type = NLA_U32 },
1879	[NDTA_THRESH2]		= { .type = NLA_U32 },
1880	[NDTA_THRESH3]		= { .type = NLA_U32 },
1881	[NDTA_GC_INTERVAL]	= { .type = NLA_U64 },
1882	[NDTA_PARMS]		= { .type = NLA_NESTED },
1883};
1884
1885static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
1886	[NDTPA_IFINDEX]			= { .type = NLA_U32 },
1887	[NDTPA_QUEUE_LEN]		= { .type = NLA_U32 },
1888	[NDTPA_PROXY_QLEN]		= { .type = NLA_U32 },
1889	[NDTPA_APP_PROBES]		= { .type = NLA_U32 },
1890	[NDTPA_UCAST_PROBES]		= { .type = NLA_U32 },
1891	[NDTPA_MCAST_PROBES]		= { .type = NLA_U32 },
 
1892	[NDTPA_BASE_REACHABLE_TIME]	= { .type = NLA_U64 },
1893	[NDTPA_GC_STALETIME]		= { .type = NLA_U64 },
1894	[NDTPA_DELAY_PROBE_TIME]	= { .type = NLA_U64 },
1895	[NDTPA_RETRANS_TIME]		= { .type = NLA_U64 },
1896	[NDTPA_ANYCAST_DELAY]		= { .type = NLA_U64 },
1897	[NDTPA_PROXY_DELAY]		= { .type = NLA_U64 },
1898	[NDTPA_LOCKTIME]		= { .type = NLA_U64 },
 
1899};
1900
1901static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 
1902{
1903	struct net *net = sock_net(skb->sk);
1904	struct neigh_table *tbl;
1905	struct ndtmsg *ndtmsg;
1906	struct nlattr *tb[NDTA_MAX+1];
1907	int err;
 
1908
1909	err = nlmsg_parse(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
1910			  nl_neightbl_policy);
1911	if (err < 0)
1912		goto errout;
1913
1914	if (tb[NDTA_NAME] == NULL) {
1915		err = -EINVAL;
1916		goto errout;
1917	}
1918
1919	ndtmsg = nlmsg_data(nlh);
1920	read_lock(&neigh_tbl_lock);
1921	for (tbl = neigh_tables; tbl; tbl = tbl->next) {
 
 
 
1922		if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
1923			continue;
1924
1925		if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0)
1926			break;
 
1927	}
1928
1929	if (tbl == NULL) {
1930		err = -ENOENT;
1931		goto errout_locked;
1932	}
1933
1934	/*
1935	 * We acquire tbl->lock to be nice to the periodic timers and
1936	 * make sure they always see a consistent set of values.
1937	 */
1938	write_lock_bh(&tbl->lock);
1939
1940	if (tb[NDTA_PARMS]) {
1941		struct nlattr *tbp[NDTPA_MAX+1];
1942		struct neigh_parms *p;
1943		int i, ifindex = 0;
1944
1945		err = nla_parse_nested(tbp, NDTPA_MAX, tb[NDTA_PARMS],
1946				       nl_ntbl_parm_policy);
 
1947		if (err < 0)
1948			goto errout_tbl_lock;
1949
1950		if (tbp[NDTPA_IFINDEX])
1951			ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
1952
1953		p = lookup_neigh_parms(tbl, net, ifindex);
1954		if (p == NULL) {
1955			err = -ENOENT;
1956			goto errout_tbl_lock;
1957		}
1958
1959		for (i = 1; i <= NDTPA_MAX; i++) {
1960			if (tbp[i] == NULL)
1961				continue;
1962
1963			switch (i) {
1964			case NDTPA_QUEUE_LEN:
1965				p->queue_len = nla_get_u32(tbp[i]);
 
 
 
 
 
 
1966				break;
1967			case NDTPA_PROXY_QLEN:
1968				p->proxy_qlen = nla_get_u32(tbp[i]);
 
1969				break;
1970			case NDTPA_APP_PROBES:
1971				p->app_probes = nla_get_u32(tbp[i]);
 
1972				break;
1973			case NDTPA_UCAST_PROBES:
1974				p->ucast_probes = nla_get_u32(tbp[i]);
 
1975				break;
1976			case NDTPA_MCAST_PROBES:
1977				p->mcast_probes = nla_get_u32(tbp[i]);
 
 
 
 
 
1978				break;
1979			case NDTPA_BASE_REACHABLE_TIME:
1980				p->base_reachable_time = nla_get_msecs(tbp[i]);
 
 
 
 
 
 
 
1981				break;
1982			case NDTPA_GC_STALETIME:
1983				p->gc_staletime = nla_get_msecs(tbp[i]);
 
1984				break;
1985			case NDTPA_DELAY_PROBE_TIME:
1986				p->delay_probe_time = nla_get_msecs(tbp[i]);
 
 
 
 
 
 
1987				break;
1988			case NDTPA_RETRANS_TIME:
1989				p->retrans_time = nla_get_msecs(tbp[i]);
 
1990				break;
1991			case NDTPA_ANYCAST_DELAY:
1992				p->anycast_delay = nla_get_msecs(tbp[i]);
 
1993				break;
1994			case NDTPA_PROXY_DELAY:
1995				p->proxy_delay = nla_get_msecs(tbp[i]);
 
1996				break;
1997			case NDTPA_LOCKTIME:
1998				p->locktime = nla_get_msecs(tbp[i]);
 
1999				break;
2000			}
2001		}
2002	}
2003
 
 
 
 
 
 
2004	if (tb[NDTA_THRESH1])
2005		tbl->gc_thresh1 = nla_get_u32(tb[NDTA_THRESH1]);
2006
2007	if (tb[NDTA_THRESH2])
2008		tbl->gc_thresh2 = nla_get_u32(tb[NDTA_THRESH2]);
2009
2010	if (tb[NDTA_THRESH3])
2011		tbl->gc_thresh3 = nla_get_u32(tb[NDTA_THRESH3]);
2012
2013	if (tb[NDTA_GC_INTERVAL])
2014		tbl->gc_interval = nla_get_msecs(tb[NDTA_GC_INTERVAL]);
2015
2016	err = 0;
2017
2018errout_tbl_lock:
2019	write_unlock_bh(&tbl->lock);
2020errout_locked:
2021	read_unlock(&neigh_tbl_lock);
2022errout:
2023	return err;
2024}
2025
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2026static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2027{
 
2028	struct net *net = sock_net(skb->sk);
2029	int family, tidx, nidx = 0;
2030	int tbl_skip = cb->args[0];
2031	int neigh_skip = cb->args[1];
2032	struct neigh_table *tbl;
2033
2034	family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
 
2035
2036	read_lock(&neigh_tbl_lock);
2037	for (tbl = neigh_tables, tidx = 0; tbl; tbl = tbl->next, tidx++) {
 
 
 
 
 
2038		struct neigh_parms *p;
2039
 
 
 
 
2040		if (tidx < tbl_skip || (family && tbl->family != family))
2041			continue;
2042
2043		if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).pid,
2044				       cb->nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
2045				       NLM_F_MULTI) <= 0)
2046			break;
2047
2048		for (nidx = 0, p = tbl->parms.next; p; p = p->next) {
 
 
2049			if (!net_eq(neigh_parms_net(p), net))
2050				continue;
2051
2052			if (nidx < neigh_skip)
2053				goto next;
2054
2055			if (neightbl_fill_param_info(skb, tbl, p,
2056						     NETLINK_CB(cb->skb).pid,
2057						     cb->nlh->nlmsg_seq,
2058						     RTM_NEWNEIGHTBL,
2059						     NLM_F_MULTI) <= 0)
2060				goto out;
2061		next:
2062			nidx++;
2063		}
2064
2065		neigh_skip = 0;
2066	}
2067out:
2068	read_unlock(&neigh_tbl_lock);
2069	cb->args[0] = tidx;
2070	cb->args[1] = nidx;
2071
2072	return skb->len;
2073}
2074
2075static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
2076			   u32 pid, u32 seq, int type, unsigned int flags)
2077{
 
2078	unsigned long now = jiffies;
2079	struct nda_cacheinfo ci;
2080	struct nlmsghdr *nlh;
2081	struct ndmsg *ndm;
2082
2083	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2084	if (nlh == NULL)
2085		return -EMSGSIZE;
2086
 
 
 
2087	ndm = nlmsg_data(nlh);
2088	ndm->ndm_family	 = neigh->ops->family;
2089	ndm->ndm_pad1    = 0;
2090	ndm->ndm_pad2    = 0;
2091	ndm->ndm_flags	 = neigh->flags;
2092	ndm->ndm_type	 = neigh->type;
2093	ndm->ndm_ifindex = neigh->dev->ifindex;
2094
2095	NLA_PUT(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key);
 
2096
2097	read_lock_bh(&neigh->lock);
2098	ndm->ndm_state	 = neigh->nud_state;
2099	if (neigh->nud_state & NUD_VALID) {
2100		char haddr[MAX_ADDR_LEN];
2101
2102		neigh_ha_snapshot(haddr, neigh, neigh->dev);
2103		if (nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, haddr) < 0) {
2104			read_unlock_bh(&neigh->lock);
2105			goto nla_put_failure;
2106		}
2107	}
2108
2109	ci.ndm_used	 = jiffies_to_clock_t(now - neigh->used);
2110	ci.ndm_confirmed = jiffies_to_clock_t(now - neigh->confirmed);
2111	ci.ndm_updated	 = jiffies_to_clock_t(now - neigh->updated);
2112	ci.ndm_refcnt	 = atomic_read(&neigh->refcnt) - 1;
2113	read_unlock_bh(&neigh->lock);
2114
2115	NLA_PUT_U32(skb, NDA_PROBES, atomic_read(&neigh->probes));
2116	NLA_PUT(skb, NDA_CACHEINFO, sizeof(ci), &ci);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2117
2118	return nlmsg_end(skb, nlh);
 
2119
2120nla_put_failure:
2121	nlmsg_cancel(skb, nlh);
2122	return -EMSGSIZE;
2123}
2124
2125static void neigh_update_notify(struct neighbour *neigh)
2126{
2127	call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
2128	__neigh_notify(neigh, RTM_NEWNEIGH, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2129}
2130
 
 
 
 
 
2131static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2132			    struct netlink_callback *cb)
 
2133{
2134	struct net *net = sock_net(skb->sk);
2135	struct neighbour *n;
2136	int rc, h, s_h = cb->args[1];
2137	int idx, s_idx = idx = cb->args[2];
2138	struct neigh_hash_table *nht;
 
 
 
 
2139
2140	rcu_read_lock_bh();
2141	nht = rcu_dereference_bh(tbl->nht);
2142
2143	for (h = 0; h < (1 << nht->hash_shift); h++) {
2144		if (h < s_h)
2145			continue;
2146		if (h > s_h)
2147			s_idx = 0;
2148		for (n = rcu_dereference_bh(nht->hash_buckets[h]), idx = 0;
2149		     n != NULL;
2150		     n = rcu_dereference_bh(n->next)) {
2151			if (!net_eq(dev_net(n->dev), net))
2152				continue;
2153			if (idx < s_idx)
2154				goto next;
2155			if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).pid,
 
 
 
2156					    cb->nlh->nlmsg_seq,
2157					    RTM_NEWNEIGH,
2158					    NLM_F_MULTI) <= 0) {
2159				rc = -1;
2160				goto out;
2161			}
2162next:
2163			idx++;
2164		}
2165	}
2166	rc = skb->len;
2167out:
2168	rcu_read_unlock_bh();
2169	cb->args[1] = h;
2170	cb->args[2] = idx;
2171	return rc;
2172}
2173
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2174static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2175{
 
 
2176	struct neigh_table *tbl;
2177	int t, family, s_t;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2178
2179	read_lock(&neigh_tbl_lock);
2180	family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
2181	s_t = cb->args[0];
2182
2183	for (tbl = neigh_tables, t = 0; tbl; tbl = tbl->next, t++) {
 
 
 
 
2184		if (t < s_t || (family && tbl->family != family))
2185			continue;
2186		if (t > s_t)
2187			memset(&cb->args[1], 0, sizeof(cb->args) -
2188						sizeof(cb->args[0]));
2189		if (neigh_dump_table(tbl, skb, cb) < 0)
 
 
 
 
2190			break;
2191	}
2192	read_unlock(&neigh_tbl_lock);
2193
2194	cb->args[0] = t;
2195	return skb->len;
2196}
2197
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2198void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
2199{
2200	int chain;
2201	struct neigh_hash_table *nht;
2202
2203	rcu_read_lock_bh();
2204	nht = rcu_dereference_bh(tbl->nht);
2205
2206	read_lock(&tbl->lock); /* avoid resizes */
2207	for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2208		struct neighbour *n;
2209
2210		for (n = rcu_dereference_bh(nht->hash_buckets[chain]);
2211		     n != NULL;
2212		     n = rcu_dereference_bh(n->next))
2213			cb(n, cookie);
2214	}
2215	read_unlock(&tbl->lock);
2216	rcu_read_unlock_bh();
2217}
2218EXPORT_SYMBOL(neigh_for_each);
2219
2220/* The tbl->lock must be held as a writer and BH disabled. */
2221void __neigh_for_each_release(struct neigh_table *tbl,
2222			      int (*cb)(struct neighbour *))
2223{
2224	int chain;
2225	struct neigh_hash_table *nht;
2226
2227	nht = rcu_dereference_protected(tbl->nht,
2228					lockdep_is_held(&tbl->lock));
2229	for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2230		struct neighbour *n;
2231		struct neighbour __rcu **np;
2232
2233		np = &nht->hash_buckets[chain];
2234		while ((n = rcu_dereference_protected(*np,
2235					lockdep_is_held(&tbl->lock))) != NULL) {
2236			int release;
2237
2238			write_lock(&n->lock);
2239			release = cb(n);
2240			if (release) {
2241				rcu_assign_pointer(*np,
2242					rcu_dereference_protected(n->next,
2243						lockdep_is_held(&tbl->lock)));
2244				n->dead = 1;
2245			} else
2246				np = &n->next;
2247			write_unlock(&n->lock);
2248			if (release)
2249				neigh_cleanup_and_release(n);
2250		}
2251	}
2252}
2253EXPORT_SYMBOL(__neigh_for_each_release);
2254
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2255#ifdef CONFIG_PROC_FS
2256
2257static struct neighbour *neigh_get_first(struct seq_file *seq)
2258{
2259	struct neigh_seq_state *state = seq->private;
2260	struct net *net = seq_file_net(seq);
2261	struct neigh_hash_table *nht = state->nht;
2262	struct neighbour *n = NULL;
2263	int bucket = state->bucket;
2264
2265	state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
2266	for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) {
2267		n = rcu_dereference_bh(nht->hash_buckets[bucket]);
2268
2269		while (n) {
2270			if (!net_eq(dev_net(n->dev), net))
2271				goto next;
2272			if (state->neigh_sub_iter) {
2273				loff_t fakep = 0;
2274				void *v;
2275
2276				v = state->neigh_sub_iter(state, n, &fakep);
2277				if (!v)
2278					goto next;
2279			}
2280			if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2281				break;
2282			if (n->nud_state & ~NUD_NOARP)
2283				break;
2284next:
2285			n = rcu_dereference_bh(n->next);
2286		}
2287
2288		if (n)
2289			break;
2290	}
2291	state->bucket = bucket;
2292
2293	return n;
2294}
2295
2296static struct neighbour *neigh_get_next(struct seq_file *seq,
2297					struct neighbour *n,
2298					loff_t *pos)
2299{
2300	struct neigh_seq_state *state = seq->private;
2301	struct net *net = seq_file_net(seq);
2302	struct neigh_hash_table *nht = state->nht;
2303
2304	if (state->neigh_sub_iter) {
2305		void *v = state->neigh_sub_iter(state, n, pos);
2306		if (v)
2307			return n;
2308	}
2309	n = rcu_dereference_bh(n->next);
2310
2311	while (1) {
2312		while (n) {
2313			if (!net_eq(dev_net(n->dev), net))
2314				goto next;
2315			if (state->neigh_sub_iter) {
2316				void *v = state->neigh_sub_iter(state, n, pos);
2317				if (v)
2318					return n;
2319				goto next;
2320			}
2321			if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
2322				break;
2323
2324			if (n->nud_state & ~NUD_NOARP)
2325				break;
2326next:
2327			n = rcu_dereference_bh(n->next);
2328		}
2329
2330		if (n)
2331			break;
2332
2333		if (++state->bucket >= (1 << nht->hash_shift))
2334			break;
2335
2336		n = rcu_dereference_bh(nht->hash_buckets[state->bucket]);
2337	}
2338
2339	if (n && pos)
2340		--(*pos);
2341	return n;
2342}
2343
2344static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
2345{
2346	struct neighbour *n = neigh_get_first(seq);
2347
2348	if (n) {
2349		--(*pos);
2350		while (*pos) {
2351			n = neigh_get_next(seq, n, pos);
2352			if (!n)
2353				break;
2354		}
2355	}
2356	return *pos ? NULL : n;
2357}
2358
2359static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
2360{
2361	struct neigh_seq_state *state = seq->private;
2362	struct net *net = seq_file_net(seq);
2363	struct neigh_table *tbl = state->tbl;
2364	struct pneigh_entry *pn = NULL;
2365	int bucket = state->bucket;
2366
2367	state->flags |= NEIGH_SEQ_IS_PNEIGH;
2368	for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
2369		pn = tbl->phash_buckets[bucket];
2370		while (pn && !net_eq(pneigh_net(pn), net))
2371			pn = pn->next;
2372		if (pn)
2373			break;
2374	}
2375	state->bucket = bucket;
2376
2377	return pn;
2378}
2379
2380static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
2381					    struct pneigh_entry *pn,
2382					    loff_t *pos)
2383{
2384	struct neigh_seq_state *state = seq->private;
2385	struct net *net = seq_file_net(seq);
2386	struct neigh_table *tbl = state->tbl;
2387
2388	pn = pn->next;
 
 
 
2389	while (!pn) {
2390		if (++state->bucket > PNEIGH_HASHMASK)
2391			break;
2392		pn = tbl->phash_buckets[state->bucket];
2393		while (pn && !net_eq(pneigh_net(pn), net))
2394			pn = pn->next;
2395		if (pn)
2396			break;
2397	}
2398
2399	if (pn && pos)
2400		--(*pos);
2401
2402	return pn;
2403}
2404
2405static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
2406{
2407	struct pneigh_entry *pn = pneigh_get_first(seq);
2408
2409	if (pn) {
2410		--(*pos);
2411		while (*pos) {
2412			pn = pneigh_get_next(seq, pn, pos);
2413			if (!pn)
2414				break;
2415		}
2416	}
2417	return *pos ? NULL : pn;
2418}
2419
2420static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
2421{
2422	struct neigh_seq_state *state = seq->private;
2423	void *rc;
2424	loff_t idxpos = *pos;
2425
2426	rc = neigh_get_idx(seq, &idxpos);
2427	if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2428		rc = pneigh_get_idx(seq, &idxpos);
2429
2430	return rc;
2431}
2432
2433void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
 
2434	__acquires(rcu_bh)
2435{
2436	struct neigh_seq_state *state = seq->private;
2437
2438	state->tbl = tbl;
2439	state->bucket = 0;
2440	state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
2441
2442	rcu_read_lock_bh();
2443	state->nht = rcu_dereference_bh(tbl->nht);
 
2444
2445	return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
2446}
2447EXPORT_SYMBOL(neigh_seq_start);
2448
2449void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2450{
2451	struct neigh_seq_state *state;
2452	void *rc;
2453
2454	if (v == SEQ_START_TOKEN) {
2455		rc = neigh_get_first(seq);
2456		goto out;
2457	}
2458
2459	state = seq->private;
2460	if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
2461		rc = neigh_get_next(seq, v, NULL);
2462		if (rc)
2463			goto out;
2464		if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2465			rc = pneigh_get_first(seq);
2466	} else {
2467		BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
2468		rc = pneigh_get_next(seq, v, NULL);
2469	}
2470out:
2471	++(*pos);
2472	return rc;
2473}
2474EXPORT_SYMBOL(neigh_seq_next);
2475
2476void neigh_seq_stop(struct seq_file *seq, void *v)
 
2477	__releases(rcu_bh)
2478{
 
 
 
 
2479	rcu_read_unlock_bh();
2480}
2481EXPORT_SYMBOL(neigh_seq_stop);
2482
2483/* statistics via seq_file */
2484
2485static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
2486{
2487	struct neigh_table *tbl = seq->private;
2488	int cpu;
2489
2490	if (*pos == 0)
2491		return SEQ_START_TOKEN;
2492
2493	for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
2494		if (!cpu_possible(cpu))
2495			continue;
2496		*pos = cpu+1;
2497		return per_cpu_ptr(tbl->stats, cpu);
2498	}
2499	return NULL;
2500}
2501
2502static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2503{
2504	struct neigh_table *tbl = seq->private;
2505	int cpu;
2506
2507	for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
2508		if (!cpu_possible(cpu))
2509			continue;
2510		*pos = cpu+1;
2511		return per_cpu_ptr(tbl->stats, cpu);
2512	}
 
2513	return NULL;
2514}
2515
2516static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
2517{
2518
2519}
2520
2521static int neigh_stat_seq_show(struct seq_file *seq, void *v)
2522{
2523	struct neigh_table *tbl = seq->private;
2524	struct neigh_statistics *st = v;
2525
2526	if (v == SEQ_START_TOKEN) {
2527		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\n");
2528		return 0;
2529	}
2530
2531	seq_printf(seq, "%08x  %08lx %08lx %08lx  %08lx %08lx  %08lx  "
2532			"%08lx %08lx  %08lx %08lx %08lx\n",
 
2533		   atomic_read(&tbl->entries),
2534
2535		   st->allocs,
2536		   st->destroys,
2537		   st->hash_grows,
2538
2539		   st->lookups,
2540		   st->hits,
2541
2542		   st->res_failed,
2543
2544		   st->rcv_probes_mcast,
2545		   st->rcv_probes_ucast,
2546
2547		   st->periodic_gc_runs,
2548		   st->forced_gc_runs,
2549		   st->unres_discards
 
2550		   );
2551
2552	return 0;
2553}
2554
2555static const struct seq_operations neigh_stat_seq_ops = {
2556	.start	= neigh_stat_seq_start,
2557	.next	= neigh_stat_seq_next,
2558	.stop	= neigh_stat_seq_stop,
2559	.show	= neigh_stat_seq_show,
2560};
2561
2562static int neigh_stat_seq_open(struct inode *inode, struct file *file)
2563{
2564	int ret = seq_open(file, &neigh_stat_seq_ops);
2565
2566	if (!ret) {
2567		struct seq_file *sf = file->private_data;
2568		sf->private = PDE(inode)->data;
2569	}
2570	return ret;
2571};
2572
2573static const struct file_operations neigh_stat_seq_fops = {
2574	.owner	 = THIS_MODULE,
2575	.open 	 = neigh_stat_seq_open,
2576	.read	 = seq_read,
2577	.llseek	 = seq_lseek,
2578	.release = seq_release,
2579};
2580
2581#endif /* CONFIG_PROC_FS */
2582
2583static inline size_t neigh_nlmsg_size(void)
2584{
2585	return NLMSG_ALIGN(sizeof(struct ndmsg))
2586	       + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2587	       + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */
2588	       + nla_total_size(sizeof(struct nda_cacheinfo))
2589	       + nla_total_size(4); /* NDA_PROBES */
2590}
2591
2592static void __neigh_notify(struct neighbour *n, int type, int flags)
2593{
2594	struct net *net = dev_net(n->dev);
2595	struct sk_buff *skb;
2596	int err = -ENOBUFS;
2597
2598	skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
2599	if (skb == NULL)
2600		goto errout;
2601
2602	err = neigh_fill_info(skb, n, 0, 0, type, flags);
2603	if (err < 0) {
2604		/* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
2605		WARN_ON(err == -EMSGSIZE);
2606		kfree_skb(skb);
2607		goto errout;
2608	}
2609	rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
2610	return;
2611errout:
2612	if (err < 0)
2613		rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
2614}
2615
2616#ifdef CONFIG_ARPD
2617void neigh_app_ns(struct neighbour *n)
2618{
2619	__neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST);
2620}
2621EXPORT_SYMBOL(neigh_app_ns);
2622#endif /* CONFIG_ARPD */
2623
2624#ifdef CONFIG_SYSCTL
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2625
2626#define NEIGH_VARS_MAX 19
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2627
2628static struct neigh_sysctl_table {
2629	struct ctl_table_header *sysctl_header;
2630	struct ctl_table neigh_vars[NEIGH_VARS_MAX];
2631	char *dev_name;
2632} neigh_sysctl_template __read_mostly = {
2633	.neigh_vars = {
2634		{
2635			.procname	= "mcast_solicit",
2636			.maxlen		= sizeof(int),
2637			.mode		= 0644,
2638			.proc_handler	= proc_dointvec,
2639		},
2640		{
2641			.procname	= "ucast_solicit",
2642			.maxlen		= sizeof(int),
2643			.mode		= 0644,
2644			.proc_handler	= proc_dointvec,
2645		},
2646		{
2647			.procname	= "app_solicit",
2648			.maxlen		= sizeof(int),
2649			.mode		= 0644,
2650			.proc_handler	= proc_dointvec,
2651		},
2652		{
2653			.procname	= "retrans_time",
2654			.maxlen		= sizeof(int),
2655			.mode		= 0644,
2656			.proc_handler	= proc_dointvec_userhz_jiffies,
2657		},
2658		{
2659			.procname	= "base_reachable_time",
2660			.maxlen		= sizeof(int),
2661			.mode		= 0644,
2662			.proc_handler	= proc_dointvec_jiffies,
2663		},
2664		{
2665			.procname	= "delay_first_probe_time",
2666			.maxlen		= sizeof(int),
2667			.mode		= 0644,
2668			.proc_handler	= proc_dointvec_jiffies,
2669		},
2670		{
2671			.procname	= "gc_stale_time",
2672			.maxlen		= sizeof(int),
2673			.mode		= 0644,
2674			.proc_handler	= proc_dointvec_jiffies,
2675		},
2676		{
2677			.procname	= "unres_qlen",
2678			.maxlen		= sizeof(int),
2679			.mode		= 0644,
2680			.proc_handler	= proc_dointvec,
2681		},
2682		{
2683			.procname	= "proxy_qlen",
2684			.maxlen		= sizeof(int),
2685			.mode		= 0644,
2686			.proc_handler	= proc_dointvec,
2687		},
2688		{
2689			.procname	= "anycast_delay",
2690			.maxlen		= sizeof(int),
2691			.mode		= 0644,
2692			.proc_handler	= proc_dointvec_userhz_jiffies,
2693		},
2694		{
2695			.procname	= "proxy_delay",
2696			.maxlen		= sizeof(int),
2697			.mode		= 0644,
2698			.proc_handler	= proc_dointvec_userhz_jiffies,
2699		},
2700		{
2701			.procname	= "locktime",
2702			.maxlen		= sizeof(int),
2703			.mode		= 0644,
2704			.proc_handler	= proc_dointvec_userhz_jiffies,
2705		},
2706		{
2707			.procname	= "retrans_time_ms",
2708			.maxlen		= sizeof(int),
2709			.mode		= 0644,
2710			.proc_handler	= proc_dointvec_ms_jiffies,
2711		},
2712		{
2713			.procname	= "base_reachable_time_ms",
2714			.maxlen		= sizeof(int),
2715			.mode		= 0644,
2716			.proc_handler	= proc_dointvec_ms_jiffies,
2717		},
2718		{
2719			.procname	= "gc_interval",
2720			.maxlen		= sizeof(int),
2721			.mode		= 0644,
2722			.proc_handler	= proc_dointvec_jiffies,
2723		},
2724		{
2725			.procname	= "gc_thresh1",
2726			.maxlen		= sizeof(int),
2727			.mode		= 0644,
2728			.proc_handler	= proc_dointvec,
 
 
2729		},
2730		{
2731			.procname	= "gc_thresh2",
2732			.maxlen		= sizeof(int),
2733			.mode		= 0644,
2734			.proc_handler	= proc_dointvec,
 
 
2735		},
2736		{
2737			.procname	= "gc_thresh3",
2738			.maxlen		= sizeof(int),
2739			.mode		= 0644,
2740			.proc_handler	= proc_dointvec,
 
 
2741		},
2742		{},
2743	},
2744};
2745
2746int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
2747			  char *p_name, proc_handler *handler)
2748{
 
2749	struct neigh_sysctl_table *t;
2750	const char *dev_name_source = NULL;
 
 
2751
2752#define NEIGH_CTL_PATH_ROOT	0
2753#define NEIGH_CTL_PATH_PROTO	1
2754#define NEIGH_CTL_PATH_NEIGH	2
2755#define NEIGH_CTL_PATH_DEV	3
2756
2757	struct ctl_path neigh_path[] = {
2758		{ .procname = "net",	 },
2759		{ .procname = "proto",	 },
2760		{ .procname = "neigh",	 },
2761		{ .procname = "default", },
2762		{ },
2763	};
2764
2765	t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL);
2766	if (!t)
2767		goto err;
2768
2769	t->neigh_vars[0].data  = &p->mcast_probes;
2770	t->neigh_vars[1].data  = &p->ucast_probes;
2771	t->neigh_vars[2].data  = &p->app_probes;
2772	t->neigh_vars[3].data  = &p->retrans_time;
2773	t->neigh_vars[4].data  = &p->base_reachable_time;
2774	t->neigh_vars[5].data  = &p->delay_probe_time;
2775	t->neigh_vars[6].data  = &p->gc_staletime;
2776	t->neigh_vars[7].data  = &p->queue_len;
2777	t->neigh_vars[8].data  = &p->proxy_qlen;
2778	t->neigh_vars[9].data  = &p->anycast_delay;
2779	t->neigh_vars[10].data = &p->proxy_delay;
2780	t->neigh_vars[11].data = &p->locktime;
2781	t->neigh_vars[12].data  = &p->retrans_time;
2782	t->neigh_vars[13].data  = &p->base_reachable_time;
2783
2784	if (dev) {
2785		dev_name_source = dev->name;
2786		/* Terminate the table early */
2787		memset(&t->neigh_vars[14], 0, sizeof(t->neigh_vars[14]));
 
2788	} else {
2789		dev_name_source = neigh_path[NEIGH_CTL_PATH_DEV].procname;
2790		t->neigh_vars[14].data = (int *)(p + 1);
2791		t->neigh_vars[15].data = (int *)(p + 1) + 1;
2792		t->neigh_vars[16].data = (int *)(p + 1) + 2;
2793		t->neigh_vars[17].data = (int *)(p + 1) + 3;
 
2794	}
2795
2796
2797	if (handler) {
2798		/* RetransTime */
2799		t->neigh_vars[3].proc_handler = handler;
2800		t->neigh_vars[3].extra1 = dev;
2801		/* ReachableTime */
2802		t->neigh_vars[4].proc_handler = handler;
2803		t->neigh_vars[4].extra1 = dev;
2804		/* RetransTime (in milliseconds)*/
2805		t->neigh_vars[12].proc_handler = handler;
2806		t->neigh_vars[12].extra1 = dev;
 
 
 
 
 
 
 
 
 
 
 
2807		/* ReachableTime (in milliseconds) */
2808		t->neigh_vars[13].proc_handler = handler;
2809		t->neigh_vars[13].extra1 = dev;
2810	}
2811
2812	t->dev_name = kstrdup(dev_name_source, GFP_KERNEL);
2813	if (!t->dev_name)
2814		goto free;
2815
2816	neigh_path[NEIGH_CTL_PATH_DEV].procname = t->dev_name;
2817	neigh_path[NEIGH_CTL_PATH_PROTO].procname = p_name;
 
 
 
 
2818
 
 
2819	t->sysctl_header =
2820		register_net_sysctl_table(neigh_parms_net(p), neigh_path, t->neigh_vars);
2821	if (!t->sysctl_header)
2822		goto free_procname;
2823
2824	p->sysctl_table = t;
2825	return 0;
2826
2827free_procname:
2828	kfree(t->dev_name);
2829free:
2830	kfree(t);
2831err:
2832	return -ENOBUFS;
2833}
2834EXPORT_SYMBOL(neigh_sysctl_register);
2835
2836void neigh_sysctl_unregister(struct neigh_parms *p)
2837{
2838	if (p->sysctl_table) {
2839		struct neigh_sysctl_table *t = p->sysctl_table;
2840		p->sysctl_table = NULL;
2841		unregister_sysctl_table(t->sysctl_header);
2842		kfree(t->dev_name);
2843		kfree(t);
2844	}
2845}
2846EXPORT_SYMBOL(neigh_sysctl_unregister);
2847
2848#endif	/* CONFIG_SYSCTL */
2849
2850static int __init neigh_init(void)
2851{
2852	rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL, NULL);
2853	rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL, NULL);
2854	rtnl_register(PF_UNSPEC, RTM_GETNEIGH, NULL, neigh_dump_info, NULL);
2855
2856	rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info,
2857		      NULL);
2858	rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL, NULL);
2859
2860	return 0;
2861}
2862
2863subsys_initcall(neigh_init);
2864
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);