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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
v5.9
   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 DEBUG
  45#define NEIGH_DEBUG 1
  46#define neigh_dbg(level, fmt, ...)		\
  47do {						\
  48	if (level <= NEIGH_DEBUG)		\
  49		pr_debug(fmt, ##__VA_ARGS__);	\
  50} while (0)
 
 
 
 
 
 
  51
  52#define PNEIGH_HASHMASK		0xF
  53
  54static void neigh_timer_handler(struct timer_list *t);
  55static void __neigh_notify(struct neighbour *n, int type, int flags,
  56			   u32 pid);
  57static void neigh_update_notify(struct neighbour *neigh, u32 nlmsg_pid);
  58static int pneigh_ifdown_and_unlock(struct neigh_table *tbl,
  59				    struct net_device *dev);
  60
 
  61#ifdef CONFIG_PROC_FS
  62static const struct seq_operations neigh_stat_seq_ops;
  63#endif
  64
  65/*
  66   Neighbour hash table buckets are protected with rwlock tbl->lock.
  67
  68   - All the scans/updates to hash buckets MUST be made under this lock.
  69   - NOTHING clever should be made under this lock: no callbacks
  70     to protocol backends, no attempts to send something to network.
  71     It will result in deadlocks, if backend/driver wants to use neighbour
  72     cache.
  73   - If the entry requires some non-trivial actions, increase
  74     its reference count and release table lock.
  75
  76   Neighbour entries are protected:
  77   - with reference count.
  78   - with rwlock neigh->lock
  79
  80   Reference count prevents destruction.
  81
  82   neigh->lock mainly serializes ll address data and its validity state.
  83   However, the same lock is used to protect another entry fields:
  84    - timer
  85    - resolution queue
  86
  87   Again, nothing clever shall be made under neigh->lock,
  88   the most complicated procedure, which we allow is dev->hard_header.
  89   It is supposed, that dev->hard_header is simplistic and does
  90   not make callbacks to neighbour tables.
 
 
 
  91 */
  92
 
 
  93static int neigh_blackhole(struct neighbour *neigh, struct sk_buff *skb)
  94{
  95	kfree_skb(skb);
  96	return -ENETDOWN;
  97}
  98
  99static void neigh_cleanup_and_release(struct neighbour *neigh)
 100{
 101	trace_neigh_cleanup_and_release(neigh, 0);
 102	__neigh_notify(neigh, RTM_DELNEIGH, 0, 0);
 103	call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
 
 104	neigh_release(neigh);
 105}
 106
 107/*
 108 * It is random distribution in the interval (1/2)*base...(3/2)*base.
 109 * It corresponds to default IPv6 settings and is not overridable,
 110 * because it is really reasonable choice.
 111 */
 112
 113unsigned long neigh_rand_reach_time(unsigned long base)
 114{
 115	return base ? (prandom_u32() % base) + (base >> 1) : 0;
 116}
 117EXPORT_SYMBOL(neigh_rand_reach_time);
 118
 119static void neigh_mark_dead(struct neighbour *n)
 120{
 121	n->dead = 1;
 122	if (!list_empty(&n->gc_list)) {
 123		list_del_init(&n->gc_list);
 124		atomic_dec(&n->tbl->gc_entries);
 125	}
 126}
 127
 128static void neigh_update_gc_list(struct neighbour *n)
 129{
 130	bool on_gc_list, exempt_from_gc;
 131
 132	write_lock_bh(&n->tbl->lock);
 133	write_lock(&n->lock);
 134
 135	/* remove from the gc list if new state is permanent or if neighbor
 136	 * is externally learned; otherwise entry should be on the gc list
 137	 */
 138	exempt_from_gc = n->nud_state & NUD_PERMANENT ||
 139			 n->flags & NTF_EXT_LEARNED;
 140	on_gc_list = !list_empty(&n->gc_list);
 141
 142	if (exempt_from_gc && on_gc_list) {
 143		list_del_init(&n->gc_list);
 144		atomic_dec(&n->tbl->gc_entries);
 145	} else if (!exempt_from_gc && !on_gc_list) {
 146		/* add entries to the tail; cleaning removes from the front */
 147		list_add_tail(&n->gc_list, &n->tbl->gc_list);
 148		atomic_inc(&n->tbl->gc_entries);
 149	}
 150
 151	write_unlock(&n->lock);
 152	write_unlock_bh(&n->tbl->lock);
 153}
 154
 155static bool neigh_update_ext_learned(struct neighbour *neigh, u32 flags,
 156				     int *notify)
 157{
 158	bool rc = false;
 159	u8 ndm_flags;
 160
 161	if (!(flags & NEIGH_UPDATE_F_ADMIN))
 162		return rc;
 163
 164	ndm_flags = (flags & NEIGH_UPDATE_F_EXT_LEARNED) ? NTF_EXT_LEARNED : 0;
 165	if ((neigh->flags ^ ndm_flags) & NTF_EXT_LEARNED) {
 166		if (ndm_flags & NTF_EXT_LEARNED)
 167			neigh->flags |= NTF_EXT_LEARNED;
 168		else
 169			neigh->flags &= ~NTF_EXT_LEARNED;
 170		rc = true;
 171		*notify = 1;
 172	}
 173
 174	return rc;
 175}
 176
 177static bool neigh_del(struct neighbour *n, struct neighbour __rcu **np,
 178		      struct neigh_table *tbl)
 179{
 180	bool retval = false;
 181
 182	write_lock(&n->lock);
 183	if (refcount_read(&n->refcnt) == 1) {
 184		struct neighbour *neigh;
 185
 186		neigh = rcu_dereference_protected(n->next,
 187						  lockdep_is_held(&tbl->lock));
 188		rcu_assign_pointer(*np, neigh);
 189		neigh_mark_dead(n);
 190		retval = true;
 191	}
 192	write_unlock(&n->lock);
 193	if (retval)
 194		neigh_cleanup_and_release(n);
 195	return retval;
 196}
 197
 198bool neigh_remove_one(struct neighbour *ndel, struct neigh_table *tbl)
 199{
 200	struct neigh_hash_table *nht;
 201	void *pkey = ndel->primary_key;
 202	u32 hash_val;
 203	struct neighbour *n;
 204	struct neighbour __rcu **np;
 205
 206	nht = rcu_dereference_protected(tbl->nht,
 207					lockdep_is_held(&tbl->lock));
 208	hash_val = tbl->hash(pkey, ndel->dev, nht->hash_rnd);
 209	hash_val = hash_val >> (32 - nht->hash_shift);
 210
 211	np = &nht->hash_buckets[hash_val];
 212	while ((n = rcu_dereference_protected(*np,
 213					      lockdep_is_held(&tbl->lock)))) {
 214		if (n == ndel)
 215			return neigh_del(n, np, tbl);
 216		np = &n->next;
 217	}
 218	return false;
 219}
 220
 221static int neigh_forced_gc(struct neigh_table *tbl)
 222{
 223	int max_clean = atomic_read(&tbl->gc_entries) - tbl->gc_thresh2;
 224	unsigned long tref = jiffies - 5 * HZ;
 225	struct neighbour *n, *tmp;
 226	int shrunk = 0;
 
 
 227
 228	NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
 229
 230	write_lock_bh(&tbl->lock);
 
 
 
 
 
 231
 232	list_for_each_entry_safe(n, tmp, &tbl->gc_list, gc_list) {
 233		if (refcount_read(&n->refcnt) == 1) {
 234			bool remove = false;
 235
 
 
 
 236			write_lock(&n->lock);
 237			if ((n->nud_state == NUD_FAILED) ||
 238			    time_after(tref, n->updated))
 239				remove = true;
 
 
 
 
 
 
 
 
 240			write_unlock(&n->lock);
 241
 242			if (remove && neigh_remove_one(n, tbl))
 243				shrunk++;
 244			if (shrunk >= max_clean)
 245				break;
 246		}
 247	}
 248
 249	tbl->last_flush = jiffies;
 250
 251	write_unlock_bh(&tbl->lock);
 252
 253	return shrunk;
 254}
 255
 256static void neigh_add_timer(struct neighbour *n, unsigned long when)
 257{
 258	neigh_hold(n);
 259	if (unlikely(mod_timer(&n->timer, when))) {
 260		printk("NEIGH: BUG, double timer add, state is %x\n",
 261		       n->nud_state);
 262		dump_stack();
 263	}
 264}
 265
 266static int neigh_del_timer(struct neighbour *n)
 267{
 268	if ((n->nud_state & NUD_IN_TIMER) &&
 269	    del_timer(&n->timer)) {
 270		neigh_release(n);
 271		return 1;
 272	}
 273	return 0;
 274}
 275
 276static void pneigh_queue_purge(struct sk_buff_head *list)
 277{
 278	struct sk_buff *skb;
 279
 280	while ((skb = skb_dequeue(list)) != NULL) {
 281		dev_put(skb->dev);
 282		kfree_skb(skb);
 283	}
 284}
 285
 286static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev,
 287			    bool skip_perm)
 288{
 289	int i;
 290	struct neigh_hash_table *nht;
 291
 292	nht = rcu_dereference_protected(tbl->nht,
 293					lockdep_is_held(&tbl->lock));
 294
 295	for (i = 0; i < (1 << nht->hash_shift); i++) {
 296		struct neighbour *n;
 297		struct neighbour __rcu **np = &nht->hash_buckets[i];
 298
 299		while ((n = rcu_dereference_protected(*np,
 300					lockdep_is_held(&tbl->lock))) != NULL) {
 301			if (dev && n->dev != dev) {
 302				np = &n->next;
 303				continue;
 304			}
 305			if (skip_perm && n->nud_state & NUD_PERMANENT) {
 306				np = &n->next;
 307				continue;
 308			}
 309			rcu_assign_pointer(*np,
 310				   rcu_dereference_protected(n->next,
 311						lockdep_is_held(&tbl->lock)));
 312			write_lock(&n->lock);
 313			neigh_del_timer(n);
 314			neigh_mark_dead(n);
 315			if (refcount_read(&n->refcnt) != 1) {
 
 316				/* The most unpleasant situation.
 317				   We must destroy neighbour entry,
 318				   but someone still uses it.
 319
 320				   The destroy will be delayed until
 321				   the last user releases us, but
 322				   we must kill timers etc. and move
 323				   it to safe state.
 324				 */
 325				__skb_queue_purge(&n->arp_queue);
 326				n->arp_queue_len_bytes = 0;
 327				n->output = neigh_blackhole;
 328				if (n->nud_state & NUD_VALID)
 329					n->nud_state = NUD_NOARP;
 330				else
 331					n->nud_state = NUD_NONE;
 332				neigh_dbg(2, "neigh %p is stray\n", n);
 333			}
 334			write_unlock(&n->lock);
 335			neigh_cleanup_and_release(n);
 336		}
 337	}
 338}
 339
 340void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
 341{
 342	write_lock_bh(&tbl->lock);
 343	neigh_flush_dev(tbl, dev, false);
 344	write_unlock_bh(&tbl->lock);
 345}
 346EXPORT_SYMBOL(neigh_changeaddr);
 347
 348static int __neigh_ifdown(struct neigh_table *tbl, struct net_device *dev,
 349			  bool skip_perm)
 350{
 351	write_lock_bh(&tbl->lock);
 352	neigh_flush_dev(tbl, dev, skip_perm);
 353	pneigh_ifdown_and_unlock(tbl, dev);
 
 354
 355	del_timer_sync(&tbl->proxy_timer);
 356	pneigh_queue_purge(&tbl->proxy_queue);
 357	return 0;
 358}
 359
 360int neigh_carrier_down(struct neigh_table *tbl, struct net_device *dev)
 361{
 362	__neigh_ifdown(tbl, dev, true);
 363	return 0;
 364}
 365EXPORT_SYMBOL(neigh_carrier_down);
 366
 367int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
 368{
 369	__neigh_ifdown(tbl, dev, false);
 370	return 0;
 371}
 372EXPORT_SYMBOL(neigh_ifdown);
 373
 374static struct neighbour *neigh_alloc(struct neigh_table *tbl,
 375				     struct net_device *dev,
 376				     bool exempt_from_gc)
 377{
 378	struct neighbour *n = NULL;
 379	unsigned long now = jiffies;
 380	int entries;
 381
 382	if (exempt_from_gc)
 383		goto do_alloc;
 384
 385	entries = atomic_inc_return(&tbl->gc_entries) - 1;
 386	if (entries >= tbl->gc_thresh3 ||
 387	    (entries >= tbl->gc_thresh2 &&
 388	     time_after(now, tbl->last_flush + 5 * HZ))) {
 389		if (!neigh_forced_gc(tbl) &&
 390		    entries >= tbl->gc_thresh3) {
 391			net_info_ratelimited("%s: neighbor table overflow!\n",
 392					     tbl->id);
 393			NEIGH_CACHE_STAT_INC(tbl, table_fulls);
 394			goto out_entries;
 395		}
 396	}
 397
 398do_alloc:
 399	n = kzalloc(tbl->entry_size + dev->neigh_priv_len, GFP_ATOMIC);
 400	if (!n)
 401		goto out_entries;
 402
 403	__skb_queue_head_init(&n->arp_queue);
 404	rwlock_init(&n->lock);
 405	seqlock_init(&n->ha_lock);
 406	n->updated	  = n->used = now;
 407	n->nud_state	  = NUD_NONE;
 408	n->output	  = neigh_blackhole;
 409	seqlock_init(&n->hh.hh_lock);
 410	n->parms	  = neigh_parms_clone(&tbl->parms);
 411	timer_setup(&n->timer, neigh_timer_handler, 0);
 412
 413	NEIGH_CACHE_STAT_INC(tbl, allocs);
 414	n->tbl		  = tbl;
 415	refcount_set(&n->refcnt, 1);
 416	n->dead		  = 1;
 417	INIT_LIST_HEAD(&n->gc_list);
 418
 419	atomic_inc(&tbl->entries);
 420out:
 421	return n;
 422
 423out_entries:
 424	if (!exempt_from_gc)
 425		atomic_dec(&tbl->gc_entries);
 426	goto out;
 427}
 428
 429static void neigh_get_hash_rnd(u32 *x)
 430{
 431	*x = get_random_u32() | 1;
 432}
 433
 434static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
 435{
 436	size_t size = (1 << shift) * sizeof(struct neighbour *);
 437	struct neigh_hash_table *ret;
 438	struct neighbour __rcu **buckets;
 439	int i;
 440
 441	ret = kmalloc(sizeof(*ret), GFP_ATOMIC);
 442	if (!ret)
 443		return NULL;
 444	if (size <= PAGE_SIZE) {
 445		buckets = kzalloc(size, GFP_ATOMIC);
 446	} else {
 447		buckets = (struct neighbour __rcu **)
 448			  __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
 449					   get_order(size));
 450		kmemleak_alloc(buckets, size, 1, GFP_ATOMIC);
 451	}
 452	if (!buckets) {
 453		kfree(ret);
 454		return NULL;
 455	}
 456	ret->hash_buckets = buckets;
 457	ret->hash_shift = shift;
 458	for (i = 0; i < NEIGH_NUM_HASH_RND; i++)
 459		neigh_get_hash_rnd(&ret->hash_rnd[i]);
 460	return ret;
 461}
 462
 463static void neigh_hash_free_rcu(struct rcu_head *head)
 464{
 465	struct neigh_hash_table *nht = container_of(head,
 466						    struct neigh_hash_table,
 467						    rcu);
 468	size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *);
 469	struct neighbour __rcu **buckets = nht->hash_buckets;
 470
 471	if (size <= PAGE_SIZE) {
 472		kfree(buckets);
 473	} else {
 474		kmemleak_free(buckets);
 475		free_pages((unsigned long)buckets, get_order(size));
 476	}
 477	kfree(nht);
 478}
 479
 480static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
 481						unsigned long new_shift)
 482{
 483	unsigned int i, hash;
 484	struct neigh_hash_table *new_nht, *old_nht;
 485
 486	NEIGH_CACHE_STAT_INC(tbl, hash_grows);
 487
 488	old_nht = rcu_dereference_protected(tbl->nht,
 489					    lockdep_is_held(&tbl->lock));
 490	new_nht = neigh_hash_alloc(new_shift);
 491	if (!new_nht)
 492		return old_nht;
 493
 494	for (i = 0; i < (1 << old_nht->hash_shift); i++) {
 495		struct neighbour *n, *next;
 496
 497		for (n = rcu_dereference_protected(old_nht->hash_buckets[i],
 498						   lockdep_is_held(&tbl->lock));
 499		     n != NULL;
 500		     n = next) {
 501			hash = tbl->hash(n->primary_key, n->dev,
 502					 new_nht->hash_rnd);
 503
 504			hash >>= (32 - new_nht->hash_shift);
 505			next = rcu_dereference_protected(n->next,
 506						lockdep_is_held(&tbl->lock));
 507
 508			rcu_assign_pointer(n->next,
 509					   rcu_dereference_protected(
 510						new_nht->hash_buckets[hash],
 511						lockdep_is_held(&tbl->lock)));
 512			rcu_assign_pointer(new_nht->hash_buckets[hash], n);
 513		}
 514	}
 515
 516	rcu_assign_pointer(tbl->nht, new_nht);
 517	call_rcu(&old_nht->rcu, neigh_hash_free_rcu);
 518	return new_nht;
 519}
 520
 521struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
 522			       struct net_device *dev)
 523{
 524	struct neighbour *n;
 
 
 
 525
 526	NEIGH_CACHE_STAT_INC(tbl, lookups);
 527
 528	rcu_read_lock_bh();
 529	n = __neigh_lookup_noref(tbl, pkey, dev);
 530	if (n) {
 531		if (!refcount_inc_not_zero(&n->refcnt))
 532			n = NULL;
 533		NEIGH_CACHE_STAT_INC(tbl, hits);
 
 
 
 
 
 
 
 534	}
 535
 536	rcu_read_unlock_bh();
 537	return n;
 538}
 539EXPORT_SYMBOL(neigh_lookup);
 540
 541struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
 542				     const void *pkey)
 543{
 544	struct neighbour *n;
 545	unsigned int key_len = tbl->key_len;
 546	u32 hash_val;
 547	struct neigh_hash_table *nht;
 548
 549	NEIGH_CACHE_STAT_INC(tbl, lookups);
 550
 551	rcu_read_lock_bh();
 552	nht = rcu_dereference_bh(tbl->nht);
 553	hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) >> (32 - nht->hash_shift);
 554
 555	for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
 556	     n != NULL;
 557	     n = rcu_dereference_bh(n->next)) {
 558		if (!memcmp(n->primary_key, pkey, key_len) &&
 559		    net_eq(dev_net(n->dev), net)) {
 560			if (!refcount_inc_not_zero(&n->refcnt))
 561				n = NULL;
 562			NEIGH_CACHE_STAT_INC(tbl, hits);
 563			break;
 564		}
 565	}
 566
 567	rcu_read_unlock_bh();
 568	return n;
 569}
 570EXPORT_SYMBOL(neigh_lookup_nodev);
 571
 572static struct neighbour *___neigh_create(struct neigh_table *tbl,
 573					 const void *pkey,
 574					 struct net_device *dev,
 575					 bool exempt_from_gc, bool want_ref)
 576{
 577	struct neighbour *n1, *rc, *n = neigh_alloc(tbl, dev, exempt_from_gc);
 578	u32 hash_val;
 579	unsigned int key_len = tbl->key_len;
 580	int error;
 
 581	struct neigh_hash_table *nht;
 582
 583	trace_neigh_create(tbl, dev, pkey, n, exempt_from_gc);
 584
 585	if (!n) {
 586		rc = ERR_PTR(-ENOBUFS);
 587		goto out;
 588	}
 589
 590	memcpy(n->primary_key, pkey, key_len);
 591	n->dev = dev;
 592	dev_hold(dev);
 593
 594	/* Protocol specific setup. */
 595	if (tbl->constructor &&	(error = tbl->constructor(n)) < 0) {
 596		rc = ERR_PTR(error);
 597		goto out_neigh_release;
 598	}
 599
 600	if (dev->netdev_ops->ndo_neigh_construct) {
 601		error = dev->netdev_ops->ndo_neigh_construct(dev, n);
 602		if (error < 0) {
 603			rc = ERR_PTR(error);
 604			goto out_neigh_release;
 605		}
 606	}
 607
 608	/* Device specific setup. */
 609	if (n->parms->neigh_setup &&
 610	    (error = n->parms->neigh_setup(n)) < 0) {
 611		rc = ERR_PTR(error);
 612		goto out_neigh_release;
 613	}
 614
 615	n->confirmed = jiffies - (NEIGH_VAR(n->parms, BASE_REACHABLE_TIME) << 1);
 616
 617	write_lock_bh(&tbl->lock);
 618	nht = rcu_dereference_protected(tbl->nht,
 619					lockdep_is_held(&tbl->lock));
 620
 621	if (atomic_read(&tbl->entries) > (1 << nht->hash_shift))
 622		nht = neigh_hash_grow(tbl, nht->hash_shift + 1);
 623
 624	hash_val = tbl->hash(n->primary_key, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
 625
 626	if (n->parms->dead) {
 627		rc = ERR_PTR(-EINVAL);
 628		goto out_tbl_unlock;
 629	}
 630
 631	for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val],
 632					    lockdep_is_held(&tbl->lock));
 633	     n1 != NULL;
 634	     n1 = rcu_dereference_protected(n1->next,
 635			lockdep_is_held(&tbl->lock))) {
 636		if (dev == n1->dev && !memcmp(n1->primary_key, n->primary_key, key_len)) {
 637			if (want_ref)
 638				neigh_hold(n1);
 639			rc = n1;
 640			goto out_tbl_unlock;
 641		}
 642	}
 643
 644	n->dead = 0;
 645	if (!exempt_from_gc)
 646		list_add_tail(&n->gc_list, &n->tbl->gc_list);
 647
 648	if (want_ref)
 649		neigh_hold(n);
 650	rcu_assign_pointer(n->next,
 651			   rcu_dereference_protected(nht->hash_buckets[hash_val],
 652						     lockdep_is_held(&tbl->lock)));
 653	rcu_assign_pointer(nht->hash_buckets[hash_val], n);
 654	write_unlock_bh(&tbl->lock);
 655	neigh_dbg(2, "neigh %p is created\n", n);
 656	rc = n;
 657out:
 658	return rc;
 659out_tbl_unlock:
 660	write_unlock_bh(&tbl->lock);
 661out_neigh_release:
 662	if (!exempt_from_gc)
 663		atomic_dec(&tbl->gc_entries);
 664	neigh_release(n);
 665	goto out;
 666}
 
 667
 668struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
 669				 struct net_device *dev, bool want_ref)
 670{
 671	return ___neigh_create(tbl, pkey, dev, false, want_ref);
 672}
 673EXPORT_SYMBOL(__neigh_create);
 674
 675static u32 pneigh_hash(const void *pkey, unsigned int key_len)
 676{
 677	u32 hash_val = *(u32 *)(pkey + key_len - 4);
 678	hash_val ^= (hash_val >> 16);
 679	hash_val ^= hash_val >> 8;
 680	hash_val ^= hash_val >> 4;
 681	hash_val &= PNEIGH_HASHMASK;
 682	return hash_val;
 683}
 684
 685static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n,
 686					      struct net *net,
 687					      const void *pkey,
 688					      unsigned int key_len,
 689					      struct net_device *dev)
 690{
 691	while (n) {
 692		if (!memcmp(n->key, pkey, key_len) &&
 693		    net_eq(pneigh_net(n), net) &&
 694		    (n->dev == dev || !n->dev))
 695			return n;
 696		n = n->next;
 697	}
 698	return NULL;
 699}
 700
 701struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
 702		struct net *net, const void *pkey, struct net_device *dev)
 703{
 704	unsigned int key_len = tbl->key_len;
 705	u32 hash_val = pneigh_hash(pkey, key_len);
 706
 707	return __pneigh_lookup_1(tbl->phash_buckets[hash_val],
 708				 net, pkey, key_len, dev);
 709}
 710EXPORT_SYMBOL_GPL(__pneigh_lookup);
 711
 712struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
 713				    struct net *net, const void *pkey,
 714				    struct net_device *dev, int creat)
 715{
 716	struct pneigh_entry *n;
 717	unsigned int key_len = tbl->key_len;
 718	u32 hash_val = pneigh_hash(pkey, key_len);
 719
 720	read_lock_bh(&tbl->lock);
 721	n = __pneigh_lookup_1(tbl->phash_buckets[hash_val],
 722			      net, pkey, key_len, dev);
 723	read_unlock_bh(&tbl->lock);
 724
 725	if (n || !creat)
 726		goto out;
 727
 728	ASSERT_RTNL();
 729
 730	n = kmalloc(sizeof(*n) + key_len, GFP_KERNEL);
 731	if (!n)
 732		goto out;
 733
 734	n->protocol = 0;
 735	write_pnet(&n->net, net);
 736	memcpy(n->key, pkey, key_len);
 737	n->dev = dev;
 738	if (dev)
 739		dev_hold(dev);
 740
 741	if (tbl->pconstructor && tbl->pconstructor(n)) {
 742		if (dev)
 743			dev_put(dev);
 
 744		kfree(n);
 745		n = NULL;
 746		goto out;
 747	}
 748
 749	write_lock_bh(&tbl->lock);
 750	n->next = tbl->phash_buckets[hash_val];
 751	tbl->phash_buckets[hash_val] = n;
 752	write_unlock_bh(&tbl->lock);
 753out:
 754	return n;
 755}
 756EXPORT_SYMBOL(pneigh_lookup);
 757
 758
 759int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
 760		  struct net_device *dev)
 761{
 762	struct pneigh_entry *n, **np;
 763	unsigned int key_len = tbl->key_len;
 764	u32 hash_val = pneigh_hash(pkey, key_len);
 765
 766	write_lock_bh(&tbl->lock);
 767	for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
 768	     np = &n->next) {
 769		if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
 770		    net_eq(pneigh_net(n), net)) {
 771			*np = n->next;
 772			write_unlock_bh(&tbl->lock);
 773			if (tbl->pdestructor)
 774				tbl->pdestructor(n);
 775			if (n->dev)
 776				dev_put(n->dev);
 
 777			kfree(n);
 778			return 0;
 779		}
 780	}
 781	write_unlock_bh(&tbl->lock);
 782	return -ENOENT;
 783}
 784
 785static int pneigh_ifdown_and_unlock(struct neigh_table *tbl,
 786				    struct net_device *dev)
 787{
 788	struct pneigh_entry *n, **np, *freelist = NULL;
 789	u32 h;
 790
 791	for (h = 0; h <= PNEIGH_HASHMASK; h++) {
 792		np = &tbl->phash_buckets[h];
 793		while ((n = *np) != NULL) {
 794			if (!dev || n->dev == dev) {
 795				*np = n->next;
 796				n->next = freelist;
 797				freelist = n;
 
 
 
 
 798				continue;
 799			}
 800			np = &n->next;
 801		}
 802	}
 803	write_unlock_bh(&tbl->lock);
 804	while ((n = freelist)) {
 805		freelist = n->next;
 806		n->next = NULL;
 807		if (tbl->pdestructor)
 808			tbl->pdestructor(n);
 809		if (n->dev)
 810			dev_put(n->dev);
 811		kfree(n);
 812	}
 813	return -ENOENT;
 814}
 815
 816static void neigh_parms_destroy(struct neigh_parms *parms);
 817
 818static inline void neigh_parms_put(struct neigh_parms *parms)
 819{
 820	if (refcount_dec_and_test(&parms->refcnt))
 821		neigh_parms_destroy(parms);
 822}
 823
 
 
 
 
 
 
 824/*
 825 *	neighbour must already be out of the table;
 826 *
 827 */
 828void neigh_destroy(struct neighbour *neigh)
 829{
 830	struct net_device *dev = neigh->dev;
 831
 832	NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
 833
 834	if (!neigh->dead) {
 835		pr_warn("Destroying alive neighbour %p\n", neigh);
 
 836		dump_stack();
 837		return;
 838	}
 839
 840	if (neigh_del_timer(neigh))
 841		pr_warn("Impossible event\n");
 842
 843	write_lock_bh(&neigh->lock);
 844	__skb_queue_purge(&neigh->arp_queue);
 845	write_unlock_bh(&neigh->lock);
 846	neigh->arp_queue_len_bytes = 0;
 847
 848	if (dev->netdev_ops->ndo_neigh_destroy)
 849		dev->netdev_ops->ndo_neigh_destroy(dev, neigh);
 850
 851	dev_put(dev);
 852	neigh_parms_put(neigh->parms);
 853
 854	neigh_dbg(2, "neigh %p is destroyed\n", neigh);
 855
 856	atomic_dec(&neigh->tbl->entries);
 857	kfree_rcu(neigh, rcu);
 858}
 859EXPORT_SYMBOL(neigh_destroy);
 860
 861/* Neighbour state is suspicious;
 862   disable fast path.
 863
 864   Called with write_locked neigh.
 865 */
 866static void neigh_suspect(struct neighbour *neigh)
 867{
 868	neigh_dbg(2, "neigh %p is suspected\n", neigh);
 869
 870	neigh->output = neigh->ops->output;
 871}
 872
 873/* Neighbour state is OK;
 874   enable fast path.
 875
 876   Called with write_locked neigh.
 877 */
 878static void neigh_connect(struct neighbour *neigh)
 879{
 880	neigh_dbg(2, "neigh %p is connected\n", neigh);
 881
 882	neigh->output = neigh->ops->connected_output;
 883}
 884
 885static void neigh_periodic_work(struct work_struct *work)
 886{
 887	struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work);
 888	struct neighbour *n;
 889	struct neighbour __rcu **np;
 890	unsigned int i;
 891	struct neigh_hash_table *nht;
 892
 893	NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
 894
 895	write_lock_bh(&tbl->lock);
 896	nht = rcu_dereference_protected(tbl->nht,
 897					lockdep_is_held(&tbl->lock));
 898
 899	/*
 900	 *	periodically recompute ReachableTime from random function
 901	 */
 902
 903	if (time_after(jiffies, tbl->last_rand + 300 * HZ)) {
 904		struct neigh_parms *p;
 905		tbl->last_rand = jiffies;
 906		list_for_each_entry(p, &tbl->parms_list, list)
 907			p->reachable_time =
 908				neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
 909	}
 910
 911	if (atomic_read(&tbl->entries) < tbl->gc_thresh1)
 912		goto out;
 913
 914	for (i = 0 ; i < (1 << nht->hash_shift); i++) {
 915		np = &nht->hash_buckets[i];
 916
 917		while ((n = rcu_dereference_protected(*np,
 918				lockdep_is_held(&tbl->lock))) != NULL) {
 919			unsigned int state;
 920
 921			write_lock(&n->lock);
 922
 923			state = n->nud_state;
 924			if ((state & (NUD_PERMANENT | NUD_IN_TIMER)) ||
 925			    (n->flags & NTF_EXT_LEARNED)) {
 926				write_unlock(&n->lock);
 927				goto next_elt;
 928			}
 929
 930			if (time_before(n->used, n->confirmed))
 931				n->used = n->confirmed;
 932
 933			if (refcount_read(&n->refcnt) == 1 &&
 934			    (state == NUD_FAILED ||
 935			     time_after(jiffies, n->used + NEIGH_VAR(n->parms, GC_STALETIME)))) {
 936				*np = n->next;
 937				neigh_mark_dead(n);
 938				write_unlock(&n->lock);
 939				neigh_cleanup_and_release(n);
 940				continue;
 941			}
 942			write_unlock(&n->lock);
 943
 944next_elt:
 945			np = &n->next;
 946		}
 947		/*
 948		 * It's fine to release lock here, even if hash table
 949		 * grows while we are preempted.
 950		 */
 951		write_unlock_bh(&tbl->lock);
 952		cond_resched();
 953		write_lock_bh(&tbl->lock);
 954		nht = rcu_dereference_protected(tbl->nht,
 955						lockdep_is_held(&tbl->lock));
 956	}
 957out:
 958	/* Cycle through all hash buckets every BASE_REACHABLE_TIME/2 ticks.
 959	 * ARP entry timeouts range from 1/2 BASE_REACHABLE_TIME to 3/2
 960	 * BASE_REACHABLE_TIME.
 961	 */
 962	queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
 963			      NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME) >> 1);
 964	write_unlock_bh(&tbl->lock);
 965}
 966
 967static __inline__ int neigh_max_probes(struct neighbour *n)
 968{
 969	struct neigh_parms *p = n->parms;
 970	return NEIGH_VAR(p, UCAST_PROBES) + NEIGH_VAR(p, APP_PROBES) +
 971	       (n->nud_state & NUD_PROBE ? NEIGH_VAR(p, MCAST_REPROBES) :
 972	        NEIGH_VAR(p, MCAST_PROBES));
 973}
 974
 975static void neigh_invalidate(struct neighbour *neigh)
 976	__releases(neigh->lock)
 977	__acquires(neigh->lock)
 978{
 979	struct sk_buff *skb;
 980
 981	NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
 982	neigh_dbg(2, "neigh %p is failed\n", neigh);
 983	neigh->updated = jiffies;
 984
 985	/* It is very thin place. report_unreachable is very complicated
 986	   routine. Particularly, it can hit the same neighbour entry!
 987
 988	   So that, we try to be accurate and avoid dead loop. --ANK
 989	 */
 990	while (neigh->nud_state == NUD_FAILED &&
 991	       (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
 992		write_unlock(&neigh->lock);
 993		neigh->ops->error_report(neigh, skb);
 994		write_lock(&neigh->lock);
 995	}
 996	__skb_queue_purge(&neigh->arp_queue);
 997	neigh->arp_queue_len_bytes = 0;
 998}
 999
1000static void neigh_probe(struct neighbour *neigh)
1001	__releases(neigh->lock)
1002{
1003	struct sk_buff *skb = skb_peek_tail(&neigh->arp_queue);
1004	/* keep skb alive even if arp_queue overflows */
1005	if (skb)
1006		skb = skb_clone(skb, GFP_ATOMIC);
1007	write_unlock(&neigh->lock);
1008	if (neigh->ops->solicit)
1009		neigh->ops->solicit(neigh, skb);
1010	atomic_inc(&neigh->probes);
1011	consume_skb(skb);
1012}
1013
1014/* Called when a timer expires for a neighbour entry. */
1015
1016static void neigh_timer_handler(struct timer_list *t)
1017{
1018	unsigned long now, next;
1019	struct neighbour *neigh = from_timer(neigh, t, timer);
1020	unsigned int state;
1021	int notify = 0;
1022
1023	write_lock(&neigh->lock);
1024
1025	state = neigh->nud_state;
1026	now = jiffies;
1027	next = now + HZ;
1028
1029	if (!(state & NUD_IN_TIMER))
 
 
 
1030		goto out;
 
1031
1032	if (state & NUD_REACHABLE) {
1033		if (time_before_eq(now,
1034				   neigh->confirmed + neigh->parms->reachable_time)) {
1035			neigh_dbg(2, "neigh %p is still alive\n", neigh);
1036			next = neigh->confirmed + neigh->parms->reachable_time;
1037		} else if (time_before_eq(now,
1038					  neigh->used +
1039					  NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
1040			neigh_dbg(2, "neigh %p is delayed\n", neigh);
1041			neigh->nud_state = NUD_DELAY;
1042			neigh->updated = jiffies;
1043			neigh_suspect(neigh);
1044			next = now + NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME);
1045		} else {
1046			neigh_dbg(2, "neigh %p is suspected\n", neigh);
1047			neigh->nud_state = NUD_STALE;
1048			neigh->updated = jiffies;
1049			neigh_suspect(neigh);
1050			notify = 1;
1051		}
1052	} else if (state & NUD_DELAY) {
1053		if (time_before_eq(now,
1054				   neigh->confirmed +
1055				   NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
1056			neigh_dbg(2, "neigh %p is now reachable\n", neigh);
1057			neigh->nud_state = NUD_REACHABLE;
1058			neigh->updated = jiffies;
1059			neigh_connect(neigh);
1060			notify = 1;
1061			next = neigh->confirmed + neigh->parms->reachable_time;
1062		} else {
1063			neigh_dbg(2, "neigh %p is probed\n", neigh);
1064			neigh->nud_state = NUD_PROBE;
1065			neigh->updated = jiffies;
1066			atomic_set(&neigh->probes, 0);
1067			notify = 1;
1068			next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
1069					 HZ/100);
1070		}
1071	} else {
1072		/* NUD_PROBE|NUD_INCOMPLETE */
1073		next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME), HZ/100);
1074	}
1075
1076	if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
1077	    atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
1078		neigh->nud_state = NUD_FAILED;
1079		notify = 1;
1080		neigh_invalidate(neigh);
1081		goto out;
1082	}
1083
1084	if (neigh->nud_state & NUD_IN_TIMER) {
1085		if (time_before(next, jiffies + HZ/100))
1086			next = jiffies + HZ/100;
1087		if (!mod_timer(&neigh->timer, next))
1088			neigh_hold(neigh);
1089	}
1090	if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
1091		neigh_probe(neigh);
 
 
 
 
 
 
 
1092	} else {
1093out:
1094		write_unlock(&neigh->lock);
1095	}
1096
1097	if (notify)
1098		neigh_update_notify(neigh, 0);
1099
1100	trace_neigh_timer_handler(neigh, 0);
1101
1102	neigh_release(neigh);
1103}
1104
1105int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
1106{
1107	int rc;
1108	bool immediate_probe = false;
1109
1110	write_lock_bh(&neigh->lock);
1111
1112	rc = 0;
1113	if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
1114		goto out_unlock_bh;
1115	if (neigh->dead)
1116		goto out_dead;
1117
1118	if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
1119		if (NEIGH_VAR(neigh->parms, MCAST_PROBES) +
1120		    NEIGH_VAR(neigh->parms, APP_PROBES)) {
1121			unsigned long next, now = jiffies;
1122
1123			atomic_set(&neigh->probes,
1124				   NEIGH_VAR(neigh->parms, UCAST_PROBES));
1125			neigh_del_timer(neigh);
1126			neigh->nud_state     = NUD_INCOMPLETE;
1127			neigh->updated = now;
1128			next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
1129					 HZ/100);
1130			neigh_add_timer(neigh, next);
1131			immediate_probe = true;
1132		} else {
1133			neigh->nud_state = NUD_FAILED;
1134			neigh->updated = jiffies;
1135			write_unlock_bh(&neigh->lock);
1136
1137			kfree_skb(skb);
1138			return 1;
1139		}
1140	} else if (neigh->nud_state & NUD_STALE) {
1141		neigh_dbg(2, "neigh %p is delayed\n", neigh);
1142		neigh_del_timer(neigh);
1143		neigh->nud_state = NUD_DELAY;
1144		neigh->updated = jiffies;
1145		neigh_add_timer(neigh, jiffies +
1146				NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME));
1147	}
1148
1149	if (neigh->nud_state == NUD_INCOMPLETE) {
1150		if (skb) {
1151			while (neigh->arp_queue_len_bytes + skb->truesize >
1152			       NEIGH_VAR(neigh->parms, QUEUE_LEN_BYTES)) {
1153				struct sk_buff *buff;
1154
1155				buff = __skb_dequeue(&neigh->arp_queue);
1156				if (!buff)
1157					break;
1158				neigh->arp_queue_len_bytes -= buff->truesize;
1159				kfree_skb(buff);
1160				NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
1161			}
1162			skb_dst_force(skb);
1163			__skb_queue_tail(&neigh->arp_queue, skb);
1164			neigh->arp_queue_len_bytes += skb->truesize;
1165		}
1166		rc = 1;
1167	}
1168out_unlock_bh:
1169	if (immediate_probe)
1170		neigh_probe(neigh);
1171	else
1172		write_unlock(&neigh->lock);
1173	local_bh_enable();
1174	trace_neigh_event_send_done(neigh, rc);
1175	return rc;
1176
1177out_dead:
1178	if (neigh->nud_state & NUD_STALE)
1179		goto out_unlock_bh;
1180	write_unlock_bh(&neigh->lock);
1181	kfree_skb(skb);
1182	trace_neigh_event_send_dead(neigh, 1);
1183	return 1;
1184}
1185EXPORT_SYMBOL(__neigh_event_send);
1186
1187static void neigh_update_hhs(struct neighbour *neigh)
1188{
1189	struct hh_cache *hh;
1190	void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
1191		= NULL;
1192
1193	if (neigh->dev->header_ops)
1194		update = neigh->dev->header_ops->cache_update;
1195
1196	if (update) {
1197		hh = &neigh->hh;
1198		if (READ_ONCE(hh->hh_len)) {
1199			write_seqlock_bh(&hh->hh_lock);
1200			update(hh, neigh->dev, neigh->ha);
1201			write_sequnlock_bh(&hh->hh_lock);
1202		}
1203	}
1204}
1205
1206
1207
1208/* Generic update routine.
1209   -- lladdr is new lladdr or NULL, if it is not supplied.
1210   -- new    is new state.
1211   -- flags
1212	NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
1213				if it is different.
1214	NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
1215				lladdr instead of overriding it
1216				if it is different.
 
 
1217	NEIGH_UPDATE_F_ADMIN	means that the change is administrative.
1218
1219	NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
1220				NTF_ROUTER flag.
1221	NEIGH_UPDATE_F_ISROUTER	indicates if the neighbour is known as
1222				a router.
1223
1224   Caller MUST hold reference count on the entry.
1225 */
1226
1227static int __neigh_update(struct neighbour *neigh, const u8 *lladdr,
1228			  u8 new, u32 flags, u32 nlmsg_pid,
1229			  struct netlink_ext_ack *extack)
1230{
1231	bool ext_learn_change = false;
1232	u8 old;
1233	int err;
1234	int notify = 0;
1235	struct net_device *dev;
1236	int update_isrouter = 0;
1237
1238	trace_neigh_update(neigh, lladdr, new, flags, nlmsg_pid);
1239
1240	write_lock_bh(&neigh->lock);
1241
1242	dev    = neigh->dev;
1243	old    = neigh->nud_state;
1244	err    = -EPERM;
1245
1246	if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
1247	    (old & (NUD_NOARP | NUD_PERMANENT)))
1248		goto out;
1249	if (neigh->dead) {
1250		NL_SET_ERR_MSG(extack, "Neighbor entry is now dead");
1251		goto out;
1252	}
1253
1254	ext_learn_change = neigh_update_ext_learned(neigh, flags, &notify);
1255
1256	if (!(new & NUD_VALID)) {
1257		neigh_del_timer(neigh);
1258		if (old & NUD_CONNECTED)
1259			neigh_suspect(neigh);
1260		neigh->nud_state = new;
1261		err = 0;
1262		notify = old & NUD_VALID;
1263		if ((old & (NUD_INCOMPLETE | NUD_PROBE)) &&
1264		    (new & NUD_FAILED)) {
1265			neigh_invalidate(neigh);
1266			notify = 1;
1267		}
1268		goto out;
1269	}
1270
1271	/* Compare new lladdr with cached one */
1272	if (!dev->addr_len) {
1273		/* First case: device needs no address. */
1274		lladdr = neigh->ha;
1275	} else if (lladdr) {
1276		/* The second case: if something is already cached
1277		   and a new address is proposed:
1278		   - compare new & old
1279		   - if they are different, check override flag
1280		 */
1281		if ((old & NUD_VALID) &&
1282		    !memcmp(lladdr, neigh->ha, dev->addr_len))
1283			lladdr = neigh->ha;
1284	} else {
1285		/* No address is supplied; if we know something,
1286		   use it, otherwise discard the request.
1287		 */
1288		err = -EINVAL;
1289		if (!(old & NUD_VALID)) {
1290			NL_SET_ERR_MSG(extack, "No link layer address given");
1291			goto out;
1292		}
1293		lladdr = neigh->ha;
1294	}
1295
1296	/* Update confirmed timestamp for neighbour entry after we
1297	 * received ARP packet even if it doesn't change IP to MAC binding.
1298	 */
1299	if (new & NUD_CONNECTED)
1300		neigh->confirmed = jiffies;
 
1301
1302	/* If entry was valid and address is not changed,
1303	   do not change entry state, if new one is STALE.
1304	 */
1305	err = 0;
1306	update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1307	if (old & NUD_VALID) {
1308		if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
1309			update_isrouter = 0;
1310			if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
1311			    (old & NUD_CONNECTED)) {
1312				lladdr = neigh->ha;
1313				new = NUD_STALE;
1314			} else
1315				goto out;
1316		} else {
1317			if (lladdr == neigh->ha && new == NUD_STALE &&
1318			    !(flags & NEIGH_UPDATE_F_ADMIN))
 
 
1319				new = old;
1320		}
1321	}
1322
1323	/* Update timestamp only once we know we will make a change to the
1324	 * neighbour entry. Otherwise we risk to move the locktime window with
1325	 * noop updates and ignore relevant ARP updates.
1326	 */
1327	if (new != old || lladdr != neigh->ha)
1328		neigh->updated = jiffies;
1329
1330	if (new != old) {
1331		neigh_del_timer(neigh);
1332		if (new & NUD_PROBE)
1333			atomic_set(&neigh->probes, 0);
1334		if (new & NUD_IN_TIMER)
1335			neigh_add_timer(neigh, (jiffies +
1336						((new & NUD_REACHABLE) ?
1337						 neigh->parms->reachable_time :
1338						 0)));
1339		neigh->nud_state = new;
1340		notify = 1;
1341	}
1342
1343	if (lladdr != neigh->ha) {
1344		write_seqlock(&neigh->ha_lock);
1345		memcpy(&neigh->ha, lladdr, dev->addr_len);
1346		write_sequnlock(&neigh->ha_lock);
1347		neigh_update_hhs(neigh);
1348		if (!(new & NUD_CONNECTED))
1349			neigh->confirmed = jiffies -
1350				      (NEIGH_VAR(neigh->parms, BASE_REACHABLE_TIME) << 1);
1351		notify = 1;
1352	}
1353	if (new == old)
1354		goto out;
1355	if (new & NUD_CONNECTED)
1356		neigh_connect(neigh);
1357	else
1358		neigh_suspect(neigh);
1359	if (!(old & NUD_VALID)) {
1360		struct sk_buff *skb;
1361
1362		/* Again: avoid dead loop if something went wrong */
1363
1364		while (neigh->nud_state & NUD_VALID &&
1365		       (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1366			struct dst_entry *dst = skb_dst(skb);
1367			struct neighbour *n2, *n1 = neigh;
1368			write_unlock_bh(&neigh->lock);
1369
1370			rcu_read_lock();
1371
1372			/* Why not just use 'neigh' as-is?  The problem is that
1373			 * things such as shaper, eql, and sch_teql can end up
1374			 * using alternative, different, neigh objects to output
1375			 * the packet in the output path.  So what we need to do
1376			 * here is re-lookup the top-level neigh in the path so
1377			 * we can reinject the packet there.
1378			 */
1379			n2 = NULL;
1380			if (dst) {
1381				n2 = dst_neigh_lookup_skb(dst, skb);
1382				if (n2)
1383					n1 = n2;
1384			}
1385			n1->output(n1, skb);
1386			if (n2)
1387				neigh_release(n2);
1388			rcu_read_unlock();
1389
1390			write_lock_bh(&neigh->lock);
1391		}
1392		__skb_queue_purge(&neigh->arp_queue);
1393		neigh->arp_queue_len_bytes = 0;
1394	}
1395out:
1396	if (update_isrouter)
1397		neigh_update_is_router(neigh, flags, &notify);
 
 
 
1398	write_unlock_bh(&neigh->lock);
1399
1400	if (((new ^ old) & NUD_PERMANENT) || ext_learn_change)
1401		neigh_update_gc_list(neigh);
1402
1403	if (notify)
1404		neigh_update_notify(neigh, nlmsg_pid);
1405
1406	trace_neigh_update_done(neigh, err);
1407
1408	return err;
1409}
1410
1411int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
1412		 u32 flags, u32 nlmsg_pid)
1413{
1414	return __neigh_update(neigh, lladdr, new, flags, nlmsg_pid, NULL);
1415}
1416EXPORT_SYMBOL(neigh_update);
1417
1418/* Update the neigh to listen temporarily for probe responses, even if it is
1419 * in a NUD_FAILED state. The caller has to hold neigh->lock for writing.
1420 */
1421void __neigh_set_probe_once(struct neighbour *neigh)
1422{
1423	if (neigh->dead)
1424		return;
1425	neigh->updated = jiffies;
1426	if (!(neigh->nud_state & NUD_FAILED))
1427		return;
1428	neigh->nud_state = NUD_INCOMPLETE;
1429	atomic_set(&neigh->probes, neigh_max_probes(neigh));
1430	neigh_add_timer(neigh,
1431			jiffies + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
1432				      HZ/100));
1433}
1434EXPORT_SYMBOL(__neigh_set_probe_once);
1435
1436struct neighbour *neigh_event_ns(struct neigh_table *tbl,
1437				 u8 *lladdr, void *saddr,
1438				 struct net_device *dev)
1439{
1440	struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev,
1441						 lladdr || !dev->addr_len);
1442	if (neigh)
1443		neigh_update(neigh, lladdr, NUD_STALE,
1444			     NEIGH_UPDATE_F_OVERRIDE, 0);
1445	return neigh;
1446}
1447EXPORT_SYMBOL(neigh_event_ns);
1448
1449/* called with read_lock_bh(&n->lock); */
1450static void neigh_hh_init(struct neighbour *n)
1451{
1452	struct net_device *dev = n->dev;
1453	__be16 prot = n->tbl->protocol;
1454	struct hh_cache	*hh = &n->hh;
1455
1456	write_lock_bh(&n->lock);
1457
1458	/* Only one thread can come in here and initialize the
1459	 * hh_cache entry.
1460	 */
1461	if (!hh->hh_len)
1462		dev->header_ops->cache(n, hh, prot);
1463
1464	write_unlock_bh(&n->lock);
1465}
1466
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1467/* Slow and careful. */
1468
1469int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb)
1470{
 
1471	int rc = 0;
1472
 
 
 
 
 
1473	if (!neigh_event_send(neigh, skb)) {
1474		int err;
1475		struct net_device *dev = neigh->dev;
1476		unsigned int seq;
1477
1478		if (dev->header_ops->cache && !READ_ONCE(neigh->hh.hh_len))
1479			neigh_hh_init(neigh);
1480
1481		do {
1482			__skb_pull(skb, skb_network_offset(skb));
1483			seq = read_seqbegin(&neigh->ha_lock);
1484			err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1485					      neigh->ha, NULL, skb->len);
1486		} while (read_seqretry(&neigh->ha_lock, seq));
1487
1488		if (err >= 0)
1489			rc = dev_queue_xmit(skb);
1490		else
1491			goto out_kfree_skb;
1492	}
1493out:
1494	return rc;
 
 
 
1495out_kfree_skb:
1496	rc = -EINVAL;
1497	kfree_skb(skb);
1498	goto out;
1499}
1500EXPORT_SYMBOL(neigh_resolve_output);
1501
1502/* As fast as possible without hh cache */
1503
1504int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb)
1505{
1506	struct net_device *dev = neigh->dev;
1507	unsigned int seq;
1508	int err;
1509
 
 
1510	do {
1511		__skb_pull(skb, skb_network_offset(skb));
1512		seq = read_seqbegin(&neigh->ha_lock);
1513		err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1514				      neigh->ha, NULL, skb->len);
1515	} while (read_seqretry(&neigh->ha_lock, seq));
1516
1517	if (err >= 0)
1518		err = dev_queue_xmit(skb);
1519	else {
1520		err = -EINVAL;
1521		kfree_skb(skb);
1522	}
1523	return err;
1524}
1525EXPORT_SYMBOL(neigh_connected_output);
1526
1527int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb)
1528{
1529	return dev_queue_xmit(skb);
1530}
1531EXPORT_SYMBOL(neigh_direct_output);
1532
1533static void neigh_proxy_process(struct timer_list *t)
1534{
1535	struct neigh_table *tbl = from_timer(tbl, t, proxy_timer);
1536	long sched_next = 0;
1537	unsigned long now = jiffies;
1538	struct sk_buff *skb, *n;
1539
1540	spin_lock(&tbl->proxy_queue.lock);
1541
1542	skb_queue_walk_safe(&tbl->proxy_queue, skb, n) {
1543		long tdif = NEIGH_CB(skb)->sched_next - now;
1544
1545		if (tdif <= 0) {
1546			struct net_device *dev = skb->dev;
1547
1548			__skb_unlink(skb, &tbl->proxy_queue);
1549			if (tbl->proxy_redo && netif_running(dev)) {
1550				rcu_read_lock();
1551				tbl->proxy_redo(skb);
1552				rcu_read_unlock();
1553			} else {
1554				kfree_skb(skb);
1555			}
1556
1557			dev_put(dev);
1558		} else if (!sched_next || tdif < sched_next)
1559			sched_next = tdif;
1560	}
1561	del_timer(&tbl->proxy_timer);
1562	if (sched_next)
1563		mod_timer(&tbl->proxy_timer, jiffies + sched_next);
1564	spin_unlock(&tbl->proxy_queue.lock);
1565}
1566
1567void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
1568		    struct sk_buff *skb)
1569{
1570	unsigned long now = jiffies;
 
1571
1572	unsigned long sched_next = now + (prandom_u32() %
1573					  NEIGH_VAR(p, PROXY_DELAY));
1574
1575	if (tbl->proxy_queue.qlen > NEIGH_VAR(p, PROXY_QLEN)) {
1576		kfree_skb(skb);
1577		return;
1578	}
1579
1580	NEIGH_CB(skb)->sched_next = sched_next;
1581	NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
1582
1583	spin_lock(&tbl->proxy_queue.lock);
1584	if (del_timer(&tbl->proxy_timer)) {
1585		if (time_before(tbl->proxy_timer.expires, sched_next))
1586			sched_next = tbl->proxy_timer.expires;
1587	}
1588	skb_dst_drop(skb);
1589	dev_hold(skb->dev);
1590	__skb_queue_tail(&tbl->proxy_queue, skb);
1591	mod_timer(&tbl->proxy_timer, sched_next);
1592	spin_unlock(&tbl->proxy_queue.lock);
1593}
1594EXPORT_SYMBOL(pneigh_enqueue);
1595
1596static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl,
1597						      struct net *net, int ifindex)
1598{
1599	struct neigh_parms *p;
1600
1601	list_for_each_entry(p, &tbl->parms_list, list) {
1602		if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
1603		    (!p->dev && !ifindex && net_eq(net, &init_net)))
1604			return p;
1605	}
1606
1607	return NULL;
1608}
1609
1610struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
1611				      struct neigh_table *tbl)
1612{
1613	struct neigh_parms *p;
1614	struct net *net = dev_net(dev);
1615	const struct net_device_ops *ops = dev->netdev_ops;
1616
1617	p = kmemdup(&tbl->parms, sizeof(*p), GFP_KERNEL);
 
 
 
 
1618	if (p) {
1619		p->tbl		  = tbl;
1620		refcount_set(&p->refcnt, 1);
1621		p->reachable_time =
1622				neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
1623		dev_hold(dev);
1624		p->dev = dev;
1625		write_pnet(&p->net, net);
1626		p->sysctl_table = NULL;
1627
1628		if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) {
1629			dev_put(dev);
1630			kfree(p);
1631			return NULL;
1632		}
1633
 
 
 
 
1634		write_lock_bh(&tbl->lock);
1635		list_add(&p->list, &tbl->parms.list);
 
1636		write_unlock_bh(&tbl->lock);
1637
1638		neigh_parms_data_state_cleanall(p);
1639	}
1640	return p;
1641}
1642EXPORT_SYMBOL(neigh_parms_alloc);
1643
1644static void neigh_rcu_free_parms(struct rcu_head *head)
1645{
1646	struct neigh_parms *parms =
1647		container_of(head, struct neigh_parms, rcu_head);
1648
1649	neigh_parms_put(parms);
1650}
1651
1652void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
1653{
 
 
1654	if (!parms || parms == &tbl->parms)
1655		return;
1656	write_lock_bh(&tbl->lock);
1657	list_del(&parms->list);
1658	parms->dead = 1;
 
 
 
 
 
 
 
 
 
1659	write_unlock_bh(&tbl->lock);
1660	if (parms->dev)
1661		dev_put(parms->dev);
1662	call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
1663}
1664EXPORT_SYMBOL(neigh_parms_release);
1665
1666static void neigh_parms_destroy(struct neigh_parms *parms)
1667{
 
1668	kfree(parms);
1669}
1670
1671static struct lock_class_key neigh_table_proxy_queue_class;
1672
1673static struct neigh_table *neigh_tables[NEIGH_NR_TABLES] __read_mostly;
1674
1675void neigh_table_init(int index, struct neigh_table *tbl)
1676{
1677	unsigned long now = jiffies;
1678	unsigned long phsize;
1679
1680	INIT_LIST_HEAD(&tbl->parms_list);
1681	INIT_LIST_HEAD(&tbl->gc_list);
1682	list_add(&tbl->parms.list, &tbl->parms_list);
1683	write_pnet(&tbl->parms.net, &init_net);
1684	refcount_set(&tbl->parms.refcnt, 1);
1685	tbl->parms.reachable_time =
1686			  neigh_rand_reach_time(NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME));
1687
 
 
 
 
 
1688	tbl->stats = alloc_percpu(struct neigh_statistics);
1689	if (!tbl->stats)
1690		panic("cannot create neighbour cache statistics");
1691
1692#ifdef CONFIG_PROC_FS
1693	if (!proc_create_seq_data(tbl->id, 0, init_net.proc_net_stat,
1694			      &neigh_stat_seq_ops, tbl))
1695		panic("cannot create neighbour proc dir entry");
1696#endif
1697
1698	RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3));
1699
1700	phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
1701	tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
1702
1703	if (!tbl->nht || !tbl->phash_buckets)
1704		panic("cannot allocate neighbour cache hashes");
1705
1706	if (!tbl->entry_size)
1707		tbl->entry_size = ALIGN(offsetof(struct neighbour, primary_key) +
1708					tbl->key_len, NEIGH_PRIV_ALIGN);
1709	else
1710		WARN_ON(tbl->entry_size % NEIGH_PRIV_ALIGN);
1711
1712	rwlock_init(&tbl->lock);
1713	INIT_DEFERRABLE_WORK(&tbl->gc_work, neigh_periodic_work);
1714	queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
1715			tbl->parms.reachable_time);
1716	timer_setup(&tbl->proxy_timer, neigh_proxy_process, 0);
1717	skb_queue_head_init_class(&tbl->proxy_queue,
1718			&neigh_table_proxy_queue_class);
1719
1720	tbl->last_flush = now;
1721	tbl->last_rand	= now + tbl->parms.reachable_time * 20;
 
 
1722
1723	neigh_tables[index] = tbl;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1724}
1725EXPORT_SYMBOL(neigh_table_init);
1726
1727int neigh_table_clear(int index, struct neigh_table *tbl)
1728{
1729	neigh_tables[index] = NULL;
 
1730	/* It is not clean... Fix it to unload IPv6 module safely */
1731	cancel_delayed_work_sync(&tbl->gc_work);
1732	del_timer_sync(&tbl->proxy_timer);
1733	pneigh_queue_purge(&tbl->proxy_queue);
1734	neigh_ifdown(tbl, NULL);
1735	if (atomic_read(&tbl->entries))
1736		pr_crit("neighbour leakage\n");
 
 
 
 
 
 
 
 
1737
1738	call_rcu(&rcu_dereference_protected(tbl->nht, 1)->rcu,
1739		 neigh_hash_free_rcu);
1740	tbl->nht = NULL;
1741
1742	kfree(tbl->phash_buckets);
1743	tbl->phash_buckets = NULL;
1744
1745	remove_proc_entry(tbl->id, init_net.proc_net_stat);
1746
1747	free_percpu(tbl->stats);
1748	tbl->stats = NULL;
1749
 
 
 
1750	return 0;
1751}
1752EXPORT_SYMBOL(neigh_table_clear);
1753
1754static struct neigh_table *neigh_find_table(int family)
1755{
1756	struct neigh_table *tbl = NULL;
1757
1758	switch (family) {
1759	case AF_INET:
1760		tbl = neigh_tables[NEIGH_ARP_TABLE];
1761		break;
1762	case AF_INET6:
1763		tbl = neigh_tables[NEIGH_ND_TABLE];
1764		break;
1765	case AF_DECnet:
1766		tbl = neigh_tables[NEIGH_DN_TABLE];
1767		break;
1768	}
1769
1770	return tbl;
1771}
1772
1773const struct nla_policy nda_policy[NDA_MAX+1] = {
1774	[NDA_UNSPEC]		= { .strict_start_type = NDA_NH_ID },
1775	[NDA_DST]		= { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
1776	[NDA_LLADDR]		= { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
1777	[NDA_CACHEINFO]		= { .len = sizeof(struct nda_cacheinfo) },
1778	[NDA_PROBES]		= { .type = NLA_U32 },
1779	[NDA_VLAN]		= { .type = NLA_U16 },
1780	[NDA_PORT]		= { .type = NLA_U16 },
1781	[NDA_VNI]		= { .type = NLA_U32 },
1782	[NDA_IFINDEX]		= { .type = NLA_U32 },
1783	[NDA_MASTER]		= { .type = NLA_U32 },
1784	[NDA_PROTOCOL]		= { .type = NLA_U8 },
1785	[NDA_NH_ID]		= { .type = NLA_U32 },
1786	[NDA_FDB_EXT_ATTRS]	= { .type = NLA_NESTED },
1787};
1788
1789static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh,
1790			struct netlink_ext_ack *extack)
1791{
1792	struct net *net = sock_net(skb->sk);
1793	struct ndmsg *ndm;
1794	struct nlattr *dst_attr;
1795	struct neigh_table *tbl;
1796	struct neighbour *neigh;
1797	struct net_device *dev = NULL;
1798	int err = -EINVAL;
1799
1800	ASSERT_RTNL();
1801	if (nlmsg_len(nlh) < sizeof(*ndm))
1802		goto out;
1803
1804	dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
1805	if (!dst_attr) {
1806		NL_SET_ERR_MSG(extack, "Network address not specified");
1807		goto out;
1808	}
1809
1810	ndm = nlmsg_data(nlh);
1811	if (ndm->ndm_ifindex) {
1812		dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1813		if (dev == NULL) {
1814			err = -ENODEV;
1815			goto out;
1816		}
1817	}
1818
1819	tbl = neigh_find_table(ndm->ndm_family);
1820	if (tbl == NULL)
1821		return -EAFNOSUPPORT;
 
 
 
 
 
 
 
1822
1823	if (nla_len(dst_attr) < (int)tbl->key_len) {
1824		NL_SET_ERR_MSG(extack, "Invalid network address");
1825		goto out;
1826	}
1827
1828	if (ndm->ndm_flags & NTF_PROXY) {
1829		err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
1830		goto out;
1831	}
1832
1833	if (dev == NULL)
1834		goto out;
 
 
 
1835
1836	neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
1837	if (neigh == NULL) {
1838		err = -ENOENT;
 
1839		goto out;
1840	}
1841
1842	err = __neigh_update(neigh, NULL, NUD_FAILED,
1843			     NEIGH_UPDATE_F_OVERRIDE | NEIGH_UPDATE_F_ADMIN,
1844			     NETLINK_CB(skb).portid, extack);
1845	write_lock_bh(&tbl->lock);
1846	neigh_release(neigh);
1847	neigh_remove_one(neigh, tbl);
1848	write_unlock_bh(&tbl->lock);
1849
1850out:
1851	return err;
1852}
1853
1854static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh,
1855		     struct netlink_ext_ack *extack)
1856{
1857	int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE |
1858		NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1859	struct net *net = sock_net(skb->sk);
1860	struct ndmsg *ndm;
1861	struct nlattr *tb[NDA_MAX+1];
1862	struct neigh_table *tbl;
1863	struct net_device *dev = NULL;
1864	struct neighbour *neigh;
1865	void *dst, *lladdr;
1866	u8 protocol = 0;
1867	int err;
1868
1869	ASSERT_RTNL();
1870	err = nlmsg_parse_deprecated(nlh, sizeof(*ndm), tb, NDA_MAX,
1871				     nda_policy, extack);
1872	if (err < 0)
1873		goto out;
1874
1875	err = -EINVAL;
1876	if (!tb[NDA_DST]) {
1877		NL_SET_ERR_MSG(extack, "Network address not specified");
1878		goto out;
1879	}
1880
1881	ndm = nlmsg_data(nlh);
1882	if (ndm->ndm_ifindex) {
1883		dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1884		if (dev == NULL) {
1885			err = -ENODEV;
1886			goto out;
1887		}
1888
1889		if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len) {
1890			NL_SET_ERR_MSG(extack, "Invalid link address");
1891			goto out;
1892		}
1893	}
1894
1895	tbl = neigh_find_table(ndm->ndm_family);
1896	if (tbl == NULL)
1897		return -EAFNOSUPPORT;
 
 
1898
1899	if (nla_len(tb[NDA_DST]) < (int)tbl->key_len) {
1900		NL_SET_ERR_MSG(extack, "Invalid network address");
1901		goto out;
1902	}
1903
1904	dst = nla_data(tb[NDA_DST]);
1905	lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
 
 
1906
1907	if (tb[NDA_PROTOCOL])
1908		protocol = nla_get_u8(tb[NDA_PROTOCOL]);
1909
1910	if (ndm->ndm_flags & NTF_PROXY) {
1911		struct pneigh_entry *pn;
1912
1913		err = -ENOBUFS;
1914		pn = pneigh_lookup(tbl, net, dst, dev, 1);
1915		if (pn) {
1916			pn->flags = ndm->ndm_flags;
1917			if (protocol)
1918				pn->protocol = protocol;
1919			err = 0;
1920		}
1921		goto out;
1922	}
1923
1924	if (!dev) {
1925		NL_SET_ERR_MSG(extack, "Device not specified");
1926		goto out;
1927	}
1928
1929	if (tbl->allow_add && !tbl->allow_add(dev, extack)) {
1930		err = -EINVAL;
1931		goto out;
1932	}
 
 
1933
1934	neigh = neigh_lookup(tbl, dst, dev);
1935	if (neigh == NULL) {
1936		bool exempt_from_gc;
 
 
 
 
 
 
 
 
1937
1938		if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
1939			err = -ENOENT;
1940			goto out;
1941		}
1942
1943		exempt_from_gc = ndm->ndm_state & NUD_PERMANENT ||
1944				 ndm->ndm_flags & NTF_EXT_LEARNED;
1945		neigh = ___neigh_create(tbl, dst, dev, exempt_from_gc, true);
1946		if (IS_ERR(neigh)) {
1947			err = PTR_ERR(neigh);
1948			goto out;
1949		}
1950	} else {
1951		if (nlh->nlmsg_flags & NLM_F_EXCL) {
1952			err = -EEXIST;
1953			neigh_release(neigh);
1954			goto out;
1955		}
1956
1957		if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
1958			flags &= ~(NEIGH_UPDATE_F_OVERRIDE |
1959				   NEIGH_UPDATE_F_OVERRIDE_ISROUTER);
1960	}
1961
1962	if (protocol)
1963		neigh->protocol = protocol;
1964
1965	if (ndm->ndm_flags & NTF_EXT_LEARNED)
1966		flags |= NEIGH_UPDATE_F_EXT_LEARNED;
1967
1968	if (ndm->ndm_flags & NTF_ROUTER)
1969		flags |= NEIGH_UPDATE_F_ISROUTER;
1970
1971	if (ndm->ndm_flags & NTF_USE) {
1972		neigh_event_send(neigh, NULL);
1973		err = 0;
1974	} else
1975		err = __neigh_update(neigh, lladdr, ndm->ndm_state, flags,
1976				     NETLINK_CB(skb).portid, extack);
1977
1978	neigh_release(neigh);
1979
1980out:
1981	return err;
1982}
1983
1984static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
1985{
1986	struct nlattr *nest;
1987
1988	nest = nla_nest_start_noflag(skb, NDTA_PARMS);
1989	if (nest == NULL)
1990		return -ENOBUFS;
1991
1992	if ((parms->dev &&
1993	     nla_put_u32(skb, NDTPA_IFINDEX, parms->dev->ifindex)) ||
1994	    nla_put_u32(skb, NDTPA_REFCNT, refcount_read(&parms->refcnt)) ||
1995	    nla_put_u32(skb, NDTPA_QUEUE_LENBYTES,
1996			NEIGH_VAR(parms, QUEUE_LEN_BYTES)) ||
1997	    /* approximative value for deprecated QUEUE_LEN (in packets) */
1998	    nla_put_u32(skb, NDTPA_QUEUE_LEN,
1999			NEIGH_VAR(parms, QUEUE_LEN_BYTES) / SKB_TRUESIZE(ETH_FRAME_LEN)) ||
2000	    nla_put_u32(skb, NDTPA_PROXY_QLEN, NEIGH_VAR(parms, PROXY_QLEN)) ||
2001	    nla_put_u32(skb, NDTPA_APP_PROBES, NEIGH_VAR(parms, APP_PROBES)) ||
2002	    nla_put_u32(skb, NDTPA_UCAST_PROBES,
2003			NEIGH_VAR(parms, UCAST_PROBES)) ||
2004	    nla_put_u32(skb, NDTPA_MCAST_PROBES,
2005			NEIGH_VAR(parms, MCAST_PROBES)) ||
2006	    nla_put_u32(skb, NDTPA_MCAST_REPROBES,
2007			NEIGH_VAR(parms, MCAST_REPROBES)) ||
2008	    nla_put_msecs(skb, NDTPA_REACHABLE_TIME, parms->reachable_time,
2009			  NDTPA_PAD) ||
2010	    nla_put_msecs(skb, NDTPA_BASE_REACHABLE_TIME,
2011			  NEIGH_VAR(parms, BASE_REACHABLE_TIME), NDTPA_PAD) ||
2012	    nla_put_msecs(skb, NDTPA_GC_STALETIME,
2013			  NEIGH_VAR(parms, GC_STALETIME), NDTPA_PAD) ||
2014	    nla_put_msecs(skb, NDTPA_DELAY_PROBE_TIME,
2015			  NEIGH_VAR(parms, DELAY_PROBE_TIME), NDTPA_PAD) ||
2016	    nla_put_msecs(skb, NDTPA_RETRANS_TIME,
2017			  NEIGH_VAR(parms, RETRANS_TIME), NDTPA_PAD) ||
2018	    nla_put_msecs(skb, NDTPA_ANYCAST_DELAY,
2019			  NEIGH_VAR(parms, ANYCAST_DELAY), NDTPA_PAD) ||
2020	    nla_put_msecs(skb, NDTPA_PROXY_DELAY,
2021			  NEIGH_VAR(parms, PROXY_DELAY), NDTPA_PAD) ||
2022	    nla_put_msecs(skb, NDTPA_LOCKTIME,
2023			  NEIGH_VAR(parms, LOCKTIME), NDTPA_PAD))
2024		goto nla_put_failure;
2025	return nla_nest_end(skb, nest);
2026
2027nla_put_failure:
2028	nla_nest_cancel(skb, nest);
2029	return -EMSGSIZE;
2030}
2031
2032static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
2033			      u32 pid, u32 seq, int type, int flags)
2034{
2035	struct nlmsghdr *nlh;
2036	struct ndtmsg *ndtmsg;
2037
2038	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
2039	if (nlh == NULL)
2040		return -EMSGSIZE;
2041
2042	ndtmsg = nlmsg_data(nlh);
2043
2044	read_lock_bh(&tbl->lock);
2045	ndtmsg->ndtm_family = tbl->family;
2046	ndtmsg->ndtm_pad1   = 0;
2047	ndtmsg->ndtm_pad2   = 0;
2048
2049	if (nla_put_string(skb, NDTA_NAME, tbl->id) ||
2050	    nla_put_msecs(skb, NDTA_GC_INTERVAL, tbl->gc_interval, NDTA_PAD) ||
2051	    nla_put_u32(skb, NDTA_THRESH1, tbl->gc_thresh1) ||
2052	    nla_put_u32(skb, NDTA_THRESH2, tbl->gc_thresh2) ||
2053	    nla_put_u32(skb, NDTA_THRESH3, tbl->gc_thresh3))
2054		goto nla_put_failure;
2055	{
2056		unsigned long now = jiffies;
2057		long flush_delta = now - tbl->last_flush;
2058		long rand_delta = now - tbl->last_rand;
2059		struct neigh_hash_table *nht;
2060		struct ndt_config ndc = {
2061			.ndtc_key_len		= tbl->key_len,
2062			.ndtc_entry_size	= tbl->entry_size,
2063			.ndtc_entries		= atomic_read(&tbl->entries),
2064			.ndtc_last_flush	= jiffies_to_msecs(flush_delta),
2065			.ndtc_last_rand		= jiffies_to_msecs(rand_delta),
2066			.ndtc_proxy_qlen	= tbl->proxy_queue.qlen,
2067		};
2068
2069		rcu_read_lock_bh();
2070		nht = rcu_dereference_bh(tbl->nht);
2071		ndc.ndtc_hash_rnd = nht->hash_rnd[0];
2072		ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
2073		rcu_read_unlock_bh();
2074
2075		if (nla_put(skb, NDTA_CONFIG, sizeof(ndc), &ndc))
2076			goto nla_put_failure;
2077	}
2078
2079	{
2080		int cpu;
2081		struct ndt_stats ndst;
2082
2083		memset(&ndst, 0, sizeof(ndst));
2084
2085		for_each_possible_cpu(cpu) {
2086			struct neigh_statistics	*st;
2087
2088			st = per_cpu_ptr(tbl->stats, cpu);
2089			ndst.ndts_allocs		+= st->allocs;
2090			ndst.ndts_destroys		+= st->destroys;
2091			ndst.ndts_hash_grows		+= st->hash_grows;
2092			ndst.ndts_res_failed		+= st->res_failed;
2093			ndst.ndts_lookups		+= st->lookups;
2094			ndst.ndts_hits			+= st->hits;
2095			ndst.ndts_rcv_probes_mcast	+= st->rcv_probes_mcast;
2096			ndst.ndts_rcv_probes_ucast	+= st->rcv_probes_ucast;
2097			ndst.ndts_periodic_gc_runs	+= st->periodic_gc_runs;
2098			ndst.ndts_forced_gc_runs	+= st->forced_gc_runs;
2099			ndst.ndts_table_fulls		+= st->table_fulls;
2100		}
2101
2102		if (nla_put_64bit(skb, NDTA_STATS, sizeof(ndst), &ndst,
2103				  NDTA_PAD))
2104			goto nla_put_failure;
2105	}
2106
2107	BUG_ON(tbl->parms.dev);
2108	if (neightbl_fill_parms(skb, &tbl->parms) < 0)
2109		goto nla_put_failure;
2110
2111	read_unlock_bh(&tbl->lock);
2112	nlmsg_end(skb, nlh);
2113	return 0;
2114
2115nla_put_failure:
2116	read_unlock_bh(&tbl->lock);
2117	nlmsg_cancel(skb, nlh);
2118	return -EMSGSIZE;
2119}
2120
2121static int neightbl_fill_param_info(struct sk_buff *skb,
2122				    struct neigh_table *tbl,
2123				    struct neigh_parms *parms,
2124				    u32 pid, u32 seq, int type,
2125				    unsigned int flags)
2126{
2127	struct ndtmsg *ndtmsg;
2128	struct nlmsghdr *nlh;
2129
2130	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
2131	if (nlh == NULL)
2132		return -EMSGSIZE;
2133
2134	ndtmsg = nlmsg_data(nlh);
2135
2136	read_lock_bh(&tbl->lock);
2137	ndtmsg->ndtm_family = tbl->family;
2138	ndtmsg->ndtm_pad1   = 0;
2139	ndtmsg->ndtm_pad2   = 0;
2140
2141	if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
2142	    neightbl_fill_parms(skb, parms) < 0)
2143		goto errout;
2144
2145	read_unlock_bh(&tbl->lock);
2146	nlmsg_end(skb, nlh);
2147	return 0;
2148errout:
2149	read_unlock_bh(&tbl->lock);
2150	nlmsg_cancel(skb, nlh);
2151	return -EMSGSIZE;
2152}
2153
2154static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
2155	[NDTA_NAME]		= { .type = NLA_STRING },
2156	[NDTA_THRESH1]		= { .type = NLA_U32 },
2157	[NDTA_THRESH2]		= { .type = NLA_U32 },
2158	[NDTA_THRESH3]		= { .type = NLA_U32 },
2159	[NDTA_GC_INTERVAL]	= { .type = NLA_U64 },
2160	[NDTA_PARMS]		= { .type = NLA_NESTED },
2161};
2162
2163static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
2164	[NDTPA_IFINDEX]			= { .type = NLA_U32 },
2165	[NDTPA_QUEUE_LEN]		= { .type = NLA_U32 },
2166	[NDTPA_PROXY_QLEN]		= { .type = NLA_U32 },
2167	[NDTPA_APP_PROBES]		= { .type = NLA_U32 },
2168	[NDTPA_UCAST_PROBES]		= { .type = NLA_U32 },
2169	[NDTPA_MCAST_PROBES]		= { .type = NLA_U32 },
2170	[NDTPA_MCAST_REPROBES]		= { .type = NLA_U32 },
2171	[NDTPA_BASE_REACHABLE_TIME]	= { .type = NLA_U64 },
2172	[NDTPA_GC_STALETIME]		= { .type = NLA_U64 },
2173	[NDTPA_DELAY_PROBE_TIME]	= { .type = NLA_U64 },
2174	[NDTPA_RETRANS_TIME]		= { .type = NLA_U64 },
2175	[NDTPA_ANYCAST_DELAY]		= { .type = NLA_U64 },
2176	[NDTPA_PROXY_DELAY]		= { .type = NLA_U64 },
2177	[NDTPA_LOCKTIME]		= { .type = NLA_U64 },
2178};
2179
2180static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh,
2181			struct netlink_ext_ack *extack)
2182{
2183	struct net *net = sock_net(skb->sk);
2184	struct neigh_table *tbl;
2185	struct ndtmsg *ndtmsg;
2186	struct nlattr *tb[NDTA_MAX+1];
2187	bool found = false;
2188	int err, tidx;
2189
2190	err = nlmsg_parse_deprecated(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
2191				     nl_neightbl_policy, extack);
2192	if (err < 0)
2193		goto errout;
2194
2195	if (tb[NDTA_NAME] == NULL) {
2196		err = -EINVAL;
2197		goto errout;
2198	}
2199
2200	ndtmsg = nlmsg_data(nlh);
2201
2202	for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
2203		tbl = neigh_tables[tidx];
2204		if (!tbl)
2205			continue;
2206		if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
2207			continue;
2208		if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0) {
2209			found = true;
2210			break;
2211		}
2212	}
2213
2214	if (!found)
2215		return -ENOENT;
 
 
2216
2217	/*
2218	 * We acquire tbl->lock to be nice to the periodic timers and
2219	 * make sure they always see a consistent set of values.
2220	 */
2221	write_lock_bh(&tbl->lock);
2222
2223	if (tb[NDTA_PARMS]) {
2224		struct nlattr *tbp[NDTPA_MAX+1];
2225		struct neigh_parms *p;
2226		int i, ifindex = 0;
2227
2228		err = nla_parse_nested_deprecated(tbp, NDTPA_MAX,
2229						  tb[NDTA_PARMS],
2230						  nl_ntbl_parm_policy, extack);
2231		if (err < 0)
2232			goto errout_tbl_lock;
2233
2234		if (tbp[NDTPA_IFINDEX])
2235			ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
2236
2237		p = lookup_neigh_parms(tbl, net, ifindex);
2238		if (p == NULL) {
2239			err = -ENOENT;
2240			goto errout_tbl_lock;
2241		}
2242
2243		for (i = 1; i <= NDTPA_MAX; i++) {
2244			if (tbp[i] == NULL)
2245				continue;
2246
2247			switch (i) {
2248			case NDTPA_QUEUE_LEN:
2249				NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2250					      nla_get_u32(tbp[i]) *
2251					      SKB_TRUESIZE(ETH_FRAME_LEN));
2252				break;
2253			case NDTPA_QUEUE_LENBYTES:
2254				NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2255					      nla_get_u32(tbp[i]));
2256				break;
2257			case NDTPA_PROXY_QLEN:
2258				NEIGH_VAR_SET(p, PROXY_QLEN,
2259					      nla_get_u32(tbp[i]));
2260				break;
2261			case NDTPA_APP_PROBES:
2262				NEIGH_VAR_SET(p, APP_PROBES,
2263					      nla_get_u32(tbp[i]));
2264				break;
2265			case NDTPA_UCAST_PROBES:
2266				NEIGH_VAR_SET(p, UCAST_PROBES,
2267					      nla_get_u32(tbp[i]));
2268				break;
2269			case NDTPA_MCAST_PROBES:
2270				NEIGH_VAR_SET(p, MCAST_PROBES,
2271					      nla_get_u32(tbp[i]));
2272				break;
2273			case NDTPA_MCAST_REPROBES:
2274				NEIGH_VAR_SET(p, MCAST_REPROBES,
2275					      nla_get_u32(tbp[i]));
2276				break;
2277			case NDTPA_BASE_REACHABLE_TIME:
2278				NEIGH_VAR_SET(p, BASE_REACHABLE_TIME,
2279					      nla_get_msecs(tbp[i]));
2280				/* update reachable_time as well, otherwise, the change will
2281				 * only be effective after the next time neigh_periodic_work
2282				 * decides to recompute it (can be multiple minutes)
2283				 */
2284				p->reachable_time =
2285					neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
2286				break;
2287			case NDTPA_GC_STALETIME:
2288				NEIGH_VAR_SET(p, GC_STALETIME,
2289					      nla_get_msecs(tbp[i]));
2290				break;
2291			case NDTPA_DELAY_PROBE_TIME:
2292				NEIGH_VAR_SET(p, DELAY_PROBE_TIME,
2293					      nla_get_msecs(tbp[i]));
2294				call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
2295				break;
2296			case NDTPA_RETRANS_TIME:
2297				NEIGH_VAR_SET(p, RETRANS_TIME,
2298					      nla_get_msecs(tbp[i]));
2299				break;
2300			case NDTPA_ANYCAST_DELAY:
2301				NEIGH_VAR_SET(p, ANYCAST_DELAY,
2302					      nla_get_msecs(tbp[i]));
2303				break;
2304			case NDTPA_PROXY_DELAY:
2305				NEIGH_VAR_SET(p, PROXY_DELAY,
2306					      nla_get_msecs(tbp[i]));
2307				break;
2308			case NDTPA_LOCKTIME:
2309				NEIGH_VAR_SET(p, LOCKTIME,
2310					      nla_get_msecs(tbp[i]));
2311				break;
2312			}
2313		}
2314	}
2315
2316	err = -ENOENT;
2317	if ((tb[NDTA_THRESH1] || tb[NDTA_THRESH2] ||
2318	     tb[NDTA_THRESH3] || tb[NDTA_GC_INTERVAL]) &&
2319	    !net_eq(net, &init_net))
2320		goto errout_tbl_lock;
2321
2322	if (tb[NDTA_THRESH1])
2323		tbl->gc_thresh1 = nla_get_u32(tb[NDTA_THRESH1]);
2324
2325	if (tb[NDTA_THRESH2])
2326		tbl->gc_thresh2 = nla_get_u32(tb[NDTA_THRESH2]);
2327
2328	if (tb[NDTA_THRESH3])
2329		tbl->gc_thresh3 = nla_get_u32(tb[NDTA_THRESH3]);
2330
2331	if (tb[NDTA_GC_INTERVAL])
2332		tbl->gc_interval = nla_get_msecs(tb[NDTA_GC_INTERVAL]);
2333
2334	err = 0;
2335
2336errout_tbl_lock:
2337	write_unlock_bh(&tbl->lock);
 
 
2338errout:
2339	return err;
2340}
2341
2342static int neightbl_valid_dump_info(const struct nlmsghdr *nlh,
2343				    struct netlink_ext_ack *extack)
2344{
2345	struct ndtmsg *ndtm;
2346
2347	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndtm))) {
2348		NL_SET_ERR_MSG(extack, "Invalid header for neighbor table dump request");
2349		return -EINVAL;
2350	}
2351
2352	ndtm = nlmsg_data(nlh);
2353	if (ndtm->ndtm_pad1  || ndtm->ndtm_pad2) {
2354		NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor table dump request");
2355		return -EINVAL;
2356	}
2357
2358	if (nlmsg_attrlen(nlh, sizeof(*ndtm))) {
2359		NL_SET_ERR_MSG(extack, "Invalid data after header in neighbor table dump request");
2360		return -EINVAL;
2361	}
2362
2363	return 0;
2364}
2365
2366static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2367{
2368	const struct nlmsghdr *nlh = cb->nlh;
2369	struct net *net = sock_net(skb->sk);
2370	int family, tidx, nidx = 0;
2371	int tbl_skip = cb->args[0];
2372	int neigh_skip = cb->args[1];
2373	struct neigh_table *tbl;
2374
2375	if (cb->strict_check) {
2376		int err = neightbl_valid_dump_info(nlh, cb->extack);
2377
2378		if (err < 0)
2379			return err;
2380	}
2381
2382	family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family;
2383
2384	for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
2385		struct neigh_parms *p;
2386
2387		tbl = neigh_tables[tidx];
2388		if (!tbl)
2389			continue;
2390
2391		if (tidx < tbl_skip || (family && tbl->family != family))
2392			continue;
2393
2394		if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).portid,
2395				       nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
2396				       NLM_F_MULTI) < 0)
2397			break;
2398
2399		nidx = 0;
2400		p = list_next_entry(&tbl->parms, list);
2401		list_for_each_entry_from(p, &tbl->parms_list, list) {
2402			if (!net_eq(neigh_parms_net(p), net))
2403				continue;
2404
2405			if (nidx < neigh_skip)
2406				goto next;
2407
2408			if (neightbl_fill_param_info(skb, tbl, p,
2409						     NETLINK_CB(cb->skb).portid,
2410						     nlh->nlmsg_seq,
2411						     RTM_NEWNEIGHTBL,
2412						     NLM_F_MULTI) < 0)
2413				goto out;
2414		next:
2415			nidx++;
2416		}
2417
2418		neigh_skip = 0;
2419	}
2420out:
 
2421	cb->args[0] = tidx;
2422	cb->args[1] = nidx;
2423
2424	return skb->len;
2425}
2426
2427static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
2428			   u32 pid, u32 seq, int type, unsigned int flags)
2429{
2430	unsigned long now = jiffies;
2431	struct nda_cacheinfo ci;
2432	struct nlmsghdr *nlh;
2433	struct ndmsg *ndm;
2434
2435	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2436	if (nlh == NULL)
2437		return -EMSGSIZE;
2438
2439	ndm = nlmsg_data(nlh);
2440	ndm->ndm_family	 = neigh->ops->family;
2441	ndm->ndm_pad1    = 0;
2442	ndm->ndm_pad2    = 0;
2443	ndm->ndm_flags	 = neigh->flags;
2444	ndm->ndm_type	 = neigh->type;
2445	ndm->ndm_ifindex = neigh->dev->ifindex;
2446
2447	if (nla_put(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key))
2448		goto nla_put_failure;
2449
2450	read_lock_bh(&neigh->lock);
2451	ndm->ndm_state	 = neigh->nud_state;
2452	if (neigh->nud_state & NUD_VALID) {
2453		char haddr[MAX_ADDR_LEN];
2454
2455		neigh_ha_snapshot(haddr, neigh, neigh->dev);
2456		if (nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, haddr) < 0) {
2457			read_unlock_bh(&neigh->lock);
2458			goto nla_put_failure;
2459		}
2460	}
2461
2462	ci.ndm_used	 = jiffies_to_clock_t(now - neigh->used);
2463	ci.ndm_confirmed = jiffies_to_clock_t(now - neigh->confirmed);
2464	ci.ndm_updated	 = jiffies_to_clock_t(now - neigh->updated);
2465	ci.ndm_refcnt	 = refcount_read(&neigh->refcnt) - 1;
2466	read_unlock_bh(&neigh->lock);
2467
2468	if (nla_put_u32(skb, NDA_PROBES, atomic_read(&neigh->probes)) ||
2469	    nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
2470		goto nla_put_failure;
2471
2472	if (neigh->protocol && nla_put_u8(skb, NDA_PROTOCOL, neigh->protocol))
2473		goto nla_put_failure;
2474
2475	nlmsg_end(skb, nlh);
2476	return 0;
2477
2478nla_put_failure:
2479	nlmsg_cancel(skb, nlh);
2480	return -EMSGSIZE;
2481}
2482
2483static int pneigh_fill_info(struct sk_buff *skb, struct pneigh_entry *pn,
2484			    u32 pid, u32 seq, int type, unsigned int flags,
2485			    struct neigh_table *tbl)
2486{
2487	struct nlmsghdr *nlh;
2488	struct ndmsg *ndm;
2489
2490	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2491	if (nlh == NULL)
2492		return -EMSGSIZE;
2493
2494	ndm = nlmsg_data(nlh);
2495	ndm->ndm_family	 = tbl->family;
2496	ndm->ndm_pad1    = 0;
2497	ndm->ndm_pad2    = 0;
2498	ndm->ndm_flags	 = pn->flags | NTF_PROXY;
2499	ndm->ndm_type	 = RTN_UNICAST;
2500	ndm->ndm_ifindex = pn->dev ? pn->dev->ifindex : 0;
2501	ndm->ndm_state	 = NUD_NONE;
2502
2503	if (nla_put(skb, NDA_DST, tbl->key_len, pn->key))
2504		goto nla_put_failure;
2505
2506	if (pn->protocol && nla_put_u8(skb, NDA_PROTOCOL, pn->protocol))
2507		goto nla_put_failure;
2508
2509	nlmsg_end(skb, nlh);
2510	return 0;
2511
2512nla_put_failure:
2513	nlmsg_cancel(skb, nlh);
2514	return -EMSGSIZE;
2515}
2516
2517static void neigh_update_notify(struct neighbour *neigh, u32 nlmsg_pid)
2518{
2519	call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
2520	__neigh_notify(neigh, RTM_NEWNEIGH, 0, nlmsg_pid);
2521}
2522
2523static bool neigh_master_filtered(struct net_device *dev, int master_idx)
2524{
2525	struct net_device *master;
2526
2527	if (!master_idx)
2528		return false;
2529
2530	master = dev ? netdev_master_upper_dev_get(dev) : NULL;
2531	if (!master || master->ifindex != master_idx)
2532		return true;
2533
2534	return false;
2535}
2536
2537static bool neigh_ifindex_filtered(struct net_device *dev, int filter_idx)
2538{
2539	if (filter_idx && (!dev || dev->ifindex != filter_idx))
2540		return true;
2541
2542	return false;
2543}
2544
2545struct neigh_dump_filter {
2546	int master_idx;
2547	int dev_idx;
2548};
2549
2550static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2551			    struct netlink_callback *cb,
2552			    struct neigh_dump_filter *filter)
2553{
2554	struct net *net = sock_net(skb->sk);
2555	struct neighbour *n;
2556	int rc, h, s_h = cb->args[1];
2557	int idx, s_idx = idx = cb->args[2];
2558	struct neigh_hash_table *nht;
2559	unsigned int flags = NLM_F_MULTI;
2560
2561	if (filter->dev_idx || filter->master_idx)
2562		flags |= NLM_F_DUMP_FILTERED;
2563
2564	rcu_read_lock_bh();
2565	nht = rcu_dereference_bh(tbl->nht);
2566
2567	for (h = s_h; h < (1 << nht->hash_shift); h++) {
 
 
2568		if (h > s_h)
2569			s_idx = 0;
2570		for (n = rcu_dereference_bh(nht->hash_buckets[h]), idx = 0;
2571		     n != NULL;
2572		     n = rcu_dereference_bh(n->next)) {
2573			if (idx < s_idx || !net_eq(dev_net(n->dev), net))
 
 
2574				goto next;
2575			if (neigh_ifindex_filtered(n->dev, filter->dev_idx) ||
2576			    neigh_master_filtered(n->dev, filter->master_idx))
2577				goto next;
2578			if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2579					    cb->nlh->nlmsg_seq,
2580					    RTM_NEWNEIGH,
2581					    flags) < 0) {
2582				rc = -1;
2583				goto out;
2584			}
2585next:
2586			idx++;
2587		}
2588	}
2589	rc = skb->len;
2590out:
2591	rcu_read_unlock_bh();
2592	cb->args[1] = h;
2593	cb->args[2] = idx;
2594	return rc;
2595}
2596
2597static int pneigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2598			     struct netlink_callback *cb,
2599			     struct neigh_dump_filter *filter)
2600{
2601	struct pneigh_entry *n;
2602	struct net *net = sock_net(skb->sk);
2603	int rc, h, s_h = cb->args[3];
2604	int idx, s_idx = idx = cb->args[4];
2605	unsigned int flags = NLM_F_MULTI;
2606
2607	if (filter->dev_idx || filter->master_idx)
2608		flags |= NLM_F_DUMP_FILTERED;
2609
2610	read_lock_bh(&tbl->lock);
2611
2612	for (h = s_h; h <= PNEIGH_HASHMASK; h++) {
2613		if (h > s_h)
2614			s_idx = 0;
2615		for (n = tbl->phash_buckets[h], idx = 0; n; n = n->next) {
2616			if (idx < s_idx || pneigh_net(n) != net)
2617				goto next;
2618			if (neigh_ifindex_filtered(n->dev, filter->dev_idx) ||
2619			    neigh_master_filtered(n->dev, filter->master_idx))
2620				goto next;
2621			if (pneigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2622					    cb->nlh->nlmsg_seq,
2623					    RTM_NEWNEIGH, flags, tbl) < 0) {
2624				read_unlock_bh(&tbl->lock);
2625				rc = -1;
2626				goto out;
2627			}
2628		next:
2629			idx++;
2630		}
2631	}
2632
2633	read_unlock_bh(&tbl->lock);
2634	rc = skb->len;
2635out:
2636	cb->args[3] = h;
2637	cb->args[4] = idx;
2638	return rc;
2639
2640}
2641
2642static int neigh_valid_dump_req(const struct nlmsghdr *nlh,
2643				bool strict_check,
2644				struct neigh_dump_filter *filter,
2645				struct netlink_ext_ack *extack)
2646{
2647	struct nlattr *tb[NDA_MAX + 1];
2648	int err, i;
2649
2650	if (strict_check) {
2651		struct ndmsg *ndm;
2652
2653		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) {
2654			NL_SET_ERR_MSG(extack, "Invalid header for neighbor dump request");
2655			return -EINVAL;
2656		}
2657
2658		ndm = nlmsg_data(nlh);
2659		if (ndm->ndm_pad1  || ndm->ndm_pad2  || ndm->ndm_ifindex ||
2660		    ndm->ndm_state || ndm->ndm_type) {
2661			NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor dump request");
2662			return -EINVAL;
2663		}
2664
2665		if (ndm->ndm_flags & ~NTF_PROXY) {
2666			NL_SET_ERR_MSG(extack, "Invalid flags in header for neighbor dump request");
2667			return -EINVAL;
2668		}
2669
2670		err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct ndmsg),
2671						    tb, NDA_MAX, nda_policy,
2672						    extack);
2673	} else {
2674		err = nlmsg_parse_deprecated(nlh, sizeof(struct ndmsg), tb,
2675					     NDA_MAX, nda_policy, extack);
2676	}
2677	if (err < 0)
2678		return err;
2679
2680	for (i = 0; i <= NDA_MAX; ++i) {
2681		if (!tb[i])
2682			continue;
2683
2684		/* all new attributes should require strict_check */
2685		switch (i) {
2686		case NDA_IFINDEX:
2687			filter->dev_idx = nla_get_u32(tb[i]);
2688			break;
2689		case NDA_MASTER:
2690			filter->master_idx = nla_get_u32(tb[i]);
2691			break;
2692		default:
2693			if (strict_check) {
2694				NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor dump request");
2695				return -EINVAL;
2696			}
2697		}
2698	}
2699
2700	return 0;
2701}
2702
2703static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2704{
2705	const struct nlmsghdr *nlh = cb->nlh;
2706	struct neigh_dump_filter filter = {};
2707	struct neigh_table *tbl;
2708	int t, family, s_t;
2709	int proxy = 0;
2710	int err;
2711
2712	family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family;
2713
2714	/* check for full ndmsg structure presence, family member is
2715	 * the same for both structures
2716	 */
2717	if (nlmsg_len(nlh) >= sizeof(struct ndmsg) &&
2718	    ((struct ndmsg *)nlmsg_data(nlh))->ndm_flags == NTF_PROXY)
2719		proxy = 1;
2720
2721	err = neigh_valid_dump_req(nlh, cb->strict_check, &filter, cb->extack);
2722	if (err < 0 && cb->strict_check)
2723		return err;
2724
 
 
2725	s_t = cb->args[0];
2726
2727	for (t = 0; t < NEIGH_NR_TABLES; t++) {
2728		tbl = neigh_tables[t];
2729
2730		if (!tbl)
2731			continue;
2732		if (t < s_t || (family && tbl->family != family))
2733			continue;
2734		if (t > s_t)
2735			memset(&cb->args[1], 0, sizeof(cb->args) -
2736						sizeof(cb->args[0]));
2737		if (proxy)
2738			err = pneigh_dump_table(tbl, skb, cb, &filter);
2739		else
2740			err = neigh_dump_table(tbl, skb, cb, &filter);
2741		if (err < 0)
2742			break;
2743	}
 
2744
2745	cb->args[0] = t;
2746	return skb->len;
2747}
2748
2749static int neigh_valid_get_req(const struct nlmsghdr *nlh,
2750			       struct neigh_table **tbl,
2751			       void **dst, int *dev_idx, u8 *ndm_flags,
2752			       struct netlink_ext_ack *extack)
2753{
2754	struct nlattr *tb[NDA_MAX + 1];
2755	struct ndmsg *ndm;
2756	int err, i;
2757
2758	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) {
2759		NL_SET_ERR_MSG(extack, "Invalid header for neighbor get request");
2760		return -EINVAL;
2761	}
2762
2763	ndm = nlmsg_data(nlh);
2764	if (ndm->ndm_pad1  || ndm->ndm_pad2  || ndm->ndm_state ||
2765	    ndm->ndm_type) {
2766		NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor get request");
2767		return -EINVAL;
2768	}
2769
2770	if (ndm->ndm_flags & ~NTF_PROXY) {
2771		NL_SET_ERR_MSG(extack, "Invalid flags in header for neighbor get request");
2772		return -EINVAL;
2773	}
2774
2775	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct ndmsg), tb,
2776					    NDA_MAX, nda_policy, extack);
2777	if (err < 0)
2778		return err;
2779
2780	*ndm_flags = ndm->ndm_flags;
2781	*dev_idx = ndm->ndm_ifindex;
2782	*tbl = neigh_find_table(ndm->ndm_family);
2783	if (*tbl == NULL) {
2784		NL_SET_ERR_MSG(extack, "Unsupported family in header for neighbor get request");
2785		return -EAFNOSUPPORT;
2786	}
2787
2788	for (i = 0; i <= NDA_MAX; ++i) {
2789		if (!tb[i])
2790			continue;
2791
2792		switch (i) {
2793		case NDA_DST:
2794			if (nla_len(tb[i]) != (int)(*tbl)->key_len) {
2795				NL_SET_ERR_MSG(extack, "Invalid network address in neighbor get request");
2796				return -EINVAL;
2797			}
2798			*dst = nla_data(tb[i]);
2799			break;
2800		default:
2801			NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor get request");
2802			return -EINVAL;
2803		}
2804	}
2805
2806	return 0;
2807}
2808
2809static inline size_t neigh_nlmsg_size(void)
2810{
2811	return NLMSG_ALIGN(sizeof(struct ndmsg))
2812	       + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2813	       + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */
2814	       + nla_total_size(sizeof(struct nda_cacheinfo))
2815	       + nla_total_size(4)  /* NDA_PROBES */
2816	       + nla_total_size(1); /* NDA_PROTOCOL */
2817}
2818
2819static int neigh_get_reply(struct net *net, struct neighbour *neigh,
2820			   u32 pid, u32 seq)
2821{
2822	struct sk_buff *skb;
2823	int err = 0;
2824
2825	skb = nlmsg_new(neigh_nlmsg_size(), GFP_KERNEL);
2826	if (!skb)
2827		return -ENOBUFS;
2828
2829	err = neigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0);
2830	if (err) {
2831		kfree_skb(skb);
2832		goto errout;
2833	}
2834
2835	err = rtnl_unicast(skb, net, pid);
2836errout:
2837	return err;
2838}
2839
2840static inline size_t pneigh_nlmsg_size(void)
2841{
2842	return NLMSG_ALIGN(sizeof(struct ndmsg))
2843	       + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2844	       + nla_total_size(1); /* NDA_PROTOCOL */
2845}
2846
2847static int pneigh_get_reply(struct net *net, struct pneigh_entry *neigh,
2848			    u32 pid, u32 seq, struct neigh_table *tbl)
2849{
2850	struct sk_buff *skb;
2851	int err = 0;
2852
2853	skb = nlmsg_new(pneigh_nlmsg_size(), GFP_KERNEL);
2854	if (!skb)
2855		return -ENOBUFS;
2856
2857	err = pneigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0, tbl);
2858	if (err) {
2859		kfree_skb(skb);
2860		goto errout;
2861	}
2862
2863	err = rtnl_unicast(skb, net, pid);
2864errout:
2865	return err;
2866}
2867
2868static int neigh_get(struct sk_buff *in_skb, struct nlmsghdr *nlh,
2869		     struct netlink_ext_ack *extack)
2870{
2871	struct net *net = sock_net(in_skb->sk);
2872	struct net_device *dev = NULL;
2873	struct neigh_table *tbl = NULL;
2874	struct neighbour *neigh;
2875	void *dst = NULL;
2876	u8 ndm_flags = 0;
2877	int dev_idx = 0;
2878	int err;
2879
2880	err = neigh_valid_get_req(nlh, &tbl, &dst, &dev_idx, &ndm_flags,
2881				  extack);
2882	if (err < 0)
2883		return err;
2884
2885	if (dev_idx) {
2886		dev = __dev_get_by_index(net, dev_idx);
2887		if (!dev) {
2888			NL_SET_ERR_MSG(extack, "Unknown device ifindex");
2889			return -ENODEV;
2890		}
2891	}
2892
2893	if (!dst) {
2894		NL_SET_ERR_MSG(extack, "Network address not specified");
2895		return -EINVAL;
2896	}
2897
2898	if (ndm_flags & NTF_PROXY) {
2899		struct pneigh_entry *pn;
2900
2901		pn = pneigh_lookup(tbl, net, dst, dev, 0);
2902		if (!pn) {
2903			NL_SET_ERR_MSG(extack, "Proxy neighbour entry not found");
2904			return -ENOENT;
2905		}
2906		return pneigh_get_reply(net, pn, NETLINK_CB(in_skb).portid,
2907					nlh->nlmsg_seq, tbl);
2908	}
2909
2910	if (!dev) {
2911		NL_SET_ERR_MSG(extack, "No device specified");
2912		return -EINVAL;
2913	}
2914
2915	neigh = neigh_lookup(tbl, dst, dev);
2916	if (!neigh) {
2917		NL_SET_ERR_MSG(extack, "Neighbour entry not found");
2918		return -ENOENT;
2919	}
2920
2921	err = neigh_get_reply(net, neigh, NETLINK_CB(in_skb).portid,
2922			      nlh->nlmsg_seq);
2923
2924	neigh_release(neigh);
2925
2926	return err;
2927}
2928
2929void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
2930{
2931	int chain;
2932	struct neigh_hash_table *nht;
2933
2934	rcu_read_lock_bh();
2935	nht = rcu_dereference_bh(tbl->nht);
2936
2937	read_lock(&tbl->lock); /* avoid resizes */
2938	for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2939		struct neighbour *n;
2940
2941		for (n = rcu_dereference_bh(nht->hash_buckets[chain]);
2942		     n != NULL;
2943		     n = rcu_dereference_bh(n->next))
2944			cb(n, cookie);
2945	}
2946	read_unlock(&tbl->lock);
2947	rcu_read_unlock_bh();
2948}
2949EXPORT_SYMBOL(neigh_for_each);
2950
2951/* The tbl->lock must be held as a writer and BH disabled. */
2952void __neigh_for_each_release(struct neigh_table *tbl,
2953			      int (*cb)(struct neighbour *))
2954{
2955	int chain;
2956	struct neigh_hash_table *nht;
2957
2958	nht = rcu_dereference_protected(tbl->nht,
2959					lockdep_is_held(&tbl->lock));
2960	for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2961		struct neighbour *n;
2962		struct neighbour __rcu **np;
2963
2964		np = &nht->hash_buckets[chain];
2965		while ((n = rcu_dereference_protected(*np,
2966					lockdep_is_held(&tbl->lock))) != NULL) {
2967			int release;
2968
2969			write_lock(&n->lock);
2970			release = cb(n);
2971			if (release) {
2972				rcu_assign_pointer(*np,
2973					rcu_dereference_protected(n->next,
2974						lockdep_is_held(&tbl->lock)));
2975				neigh_mark_dead(n);
2976			} else
2977				np = &n->next;
2978			write_unlock(&n->lock);
2979			if (release)
2980				neigh_cleanup_and_release(n);
2981		}
2982	}
2983}
2984EXPORT_SYMBOL(__neigh_for_each_release);
2985
2986int neigh_xmit(int index, struct net_device *dev,
2987	       const void *addr, struct sk_buff *skb)
2988{
2989	int err = -EAFNOSUPPORT;
2990	if (likely(index < NEIGH_NR_TABLES)) {
2991		struct neigh_table *tbl;
2992		struct neighbour *neigh;
2993
2994		tbl = neigh_tables[index];
2995		if (!tbl)
2996			goto out;
2997		rcu_read_lock_bh();
2998		if (index == NEIGH_ARP_TABLE) {
2999			u32 key = *((u32 *)addr);
3000
3001			neigh = __ipv4_neigh_lookup_noref(dev, key);
3002		} else {
3003			neigh = __neigh_lookup_noref(tbl, addr, dev);
3004		}
3005		if (!neigh)
3006			neigh = __neigh_create(tbl, addr, dev, false);
3007		err = PTR_ERR(neigh);
3008		if (IS_ERR(neigh)) {
3009			rcu_read_unlock_bh();
3010			goto out_kfree_skb;
3011		}
3012		err = neigh->output(neigh, skb);
3013		rcu_read_unlock_bh();
3014	}
3015	else if (index == NEIGH_LINK_TABLE) {
3016		err = dev_hard_header(skb, dev, ntohs(skb->protocol),
3017				      addr, NULL, skb->len);
3018		if (err < 0)
3019			goto out_kfree_skb;
3020		err = dev_queue_xmit(skb);
3021	}
3022out:
3023	return err;
3024out_kfree_skb:
3025	kfree_skb(skb);
3026	goto out;
3027}
3028EXPORT_SYMBOL(neigh_xmit);
3029
3030#ifdef CONFIG_PROC_FS
3031
3032static struct neighbour *neigh_get_first(struct seq_file *seq)
3033{
3034	struct neigh_seq_state *state = seq->private;
3035	struct net *net = seq_file_net(seq);
3036	struct neigh_hash_table *nht = state->nht;
3037	struct neighbour *n = NULL;
3038	int bucket;
3039
3040	state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
3041	for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) {
3042		n = rcu_dereference_bh(nht->hash_buckets[bucket]);
3043
3044		while (n) {
3045			if (!net_eq(dev_net(n->dev), net))
3046				goto next;
3047			if (state->neigh_sub_iter) {
3048				loff_t fakep = 0;
3049				void *v;
3050
3051				v = state->neigh_sub_iter(state, n, &fakep);
3052				if (!v)
3053					goto next;
3054			}
3055			if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
3056				break;
3057			if (n->nud_state & ~NUD_NOARP)
3058				break;
3059next:
3060			n = rcu_dereference_bh(n->next);
3061		}
3062
3063		if (n)
3064			break;
3065	}
3066	state->bucket = bucket;
3067
3068	return n;
3069}
3070
3071static struct neighbour *neigh_get_next(struct seq_file *seq,
3072					struct neighbour *n,
3073					loff_t *pos)
3074{
3075	struct neigh_seq_state *state = seq->private;
3076	struct net *net = seq_file_net(seq);
3077	struct neigh_hash_table *nht = state->nht;
3078
3079	if (state->neigh_sub_iter) {
3080		void *v = state->neigh_sub_iter(state, n, pos);
3081		if (v)
3082			return n;
3083	}
3084	n = rcu_dereference_bh(n->next);
3085
3086	while (1) {
3087		while (n) {
3088			if (!net_eq(dev_net(n->dev), net))
3089				goto next;
3090			if (state->neigh_sub_iter) {
3091				void *v = state->neigh_sub_iter(state, n, pos);
3092				if (v)
3093					return n;
3094				goto next;
3095			}
3096			if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
3097				break;
3098
3099			if (n->nud_state & ~NUD_NOARP)
3100				break;
3101next:
3102			n = rcu_dereference_bh(n->next);
3103		}
3104
3105		if (n)
3106			break;
3107
3108		if (++state->bucket >= (1 << nht->hash_shift))
3109			break;
3110
3111		n = rcu_dereference_bh(nht->hash_buckets[state->bucket]);
3112	}
3113
3114	if (n && pos)
3115		--(*pos);
3116	return n;
3117}
3118
3119static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
3120{
3121	struct neighbour *n = neigh_get_first(seq);
3122
3123	if (n) {
3124		--(*pos);
3125		while (*pos) {
3126			n = neigh_get_next(seq, n, pos);
3127			if (!n)
3128				break;
3129		}
3130	}
3131	return *pos ? NULL : n;
3132}
3133
3134static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
3135{
3136	struct neigh_seq_state *state = seq->private;
3137	struct net *net = seq_file_net(seq);
3138	struct neigh_table *tbl = state->tbl;
3139	struct pneigh_entry *pn = NULL;
3140	int bucket = state->bucket;
3141
3142	state->flags |= NEIGH_SEQ_IS_PNEIGH;
3143	for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
3144		pn = tbl->phash_buckets[bucket];
3145		while (pn && !net_eq(pneigh_net(pn), net))
3146			pn = pn->next;
3147		if (pn)
3148			break;
3149	}
3150	state->bucket = bucket;
3151
3152	return pn;
3153}
3154
3155static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
3156					    struct pneigh_entry *pn,
3157					    loff_t *pos)
3158{
3159	struct neigh_seq_state *state = seq->private;
3160	struct net *net = seq_file_net(seq);
3161	struct neigh_table *tbl = state->tbl;
3162
3163	do {
3164		pn = pn->next;
3165	} while (pn && !net_eq(pneigh_net(pn), net));
3166
3167	while (!pn) {
3168		if (++state->bucket > PNEIGH_HASHMASK)
3169			break;
3170		pn = tbl->phash_buckets[state->bucket];
3171		while (pn && !net_eq(pneigh_net(pn), net))
3172			pn = pn->next;
3173		if (pn)
3174			break;
3175	}
3176
3177	if (pn && pos)
3178		--(*pos);
3179
3180	return pn;
3181}
3182
3183static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
3184{
3185	struct pneigh_entry *pn = pneigh_get_first(seq);
3186
3187	if (pn) {
3188		--(*pos);
3189		while (*pos) {
3190			pn = pneigh_get_next(seq, pn, pos);
3191			if (!pn)
3192				break;
3193		}
3194	}
3195	return *pos ? NULL : pn;
3196}
3197
3198static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
3199{
3200	struct neigh_seq_state *state = seq->private;
3201	void *rc;
3202	loff_t idxpos = *pos;
3203
3204	rc = neigh_get_idx(seq, &idxpos);
3205	if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
3206		rc = pneigh_get_idx(seq, &idxpos);
3207
3208	return rc;
3209}
3210
3211void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
3212	__acquires(tbl->lock)
3213	__acquires(rcu_bh)
3214{
3215	struct neigh_seq_state *state = seq->private;
3216
3217	state->tbl = tbl;
3218	state->bucket = 0;
3219	state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
3220
3221	rcu_read_lock_bh();
3222	state->nht = rcu_dereference_bh(tbl->nht);
3223	read_lock(&tbl->lock);
3224
3225	return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
3226}
3227EXPORT_SYMBOL(neigh_seq_start);
3228
3229void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3230{
3231	struct neigh_seq_state *state;
3232	void *rc;
3233
3234	if (v == SEQ_START_TOKEN) {
3235		rc = neigh_get_first(seq);
3236		goto out;
3237	}
3238
3239	state = seq->private;
3240	if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
3241		rc = neigh_get_next(seq, v, NULL);
3242		if (rc)
3243			goto out;
3244		if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
3245			rc = pneigh_get_first(seq);
3246	} else {
3247		BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
3248		rc = pneigh_get_next(seq, v, NULL);
3249	}
3250out:
3251	++(*pos);
3252	return rc;
3253}
3254EXPORT_SYMBOL(neigh_seq_next);
3255
3256void neigh_seq_stop(struct seq_file *seq, void *v)
3257	__releases(tbl->lock)
3258	__releases(rcu_bh)
3259{
3260	struct neigh_seq_state *state = seq->private;
3261	struct neigh_table *tbl = state->tbl;
3262
3263	read_unlock(&tbl->lock);
3264	rcu_read_unlock_bh();
3265}
3266EXPORT_SYMBOL(neigh_seq_stop);
3267
3268/* statistics via seq_file */
3269
3270static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
3271{
3272	struct neigh_table *tbl = PDE_DATA(file_inode(seq->file));
3273	int cpu;
3274
3275	if (*pos == 0)
3276		return SEQ_START_TOKEN;
3277
3278	for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
3279		if (!cpu_possible(cpu))
3280			continue;
3281		*pos = cpu+1;
3282		return per_cpu_ptr(tbl->stats, cpu);
3283	}
3284	return NULL;
3285}
3286
3287static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3288{
3289	struct neigh_table *tbl = PDE_DATA(file_inode(seq->file));
3290	int cpu;
3291
3292	for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
3293		if (!cpu_possible(cpu))
3294			continue;
3295		*pos = cpu+1;
3296		return per_cpu_ptr(tbl->stats, cpu);
3297	}
3298	(*pos)++;
3299	return NULL;
3300}
3301
3302static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
3303{
3304
3305}
3306
3307static int neigh_stat_seq_show(struct seq_file *seq, void *v)
3308{
3309	struct neigh_table *tbl = PDE_DATA(file_inode(seq->file));
3310	struct neigh_statistics *st = v;
3311
3312	if (v == SEQ_START_TOKEN) {
3313		seq_printf(seq, "entries  allocs destroys hash_grows  lookups hits  res_failed  rcv_probes_mcast rcv_probes_ucast  periodic_gc_runs forced_gc_runs unresolved_discards table_fulls\n");
3314		return 0;
3315	}
3316
3317	seq_printf(seq, "%08x  %08lx %08lx %08lx  %08lx %08lx  %08lx  "
3318			"%08lx %08lx  %08lx %08lx %08lx %08lx\n",
3319		   atomic_read(&tbl->entries),
3320
3321		   st->allocs,
3322		   st->destroys,
3323		   st->hash_grows,
3324
3325		   st->lookups,
3326		   st->hits,
3327
3328		   st->res_failed,
3329
3330		   st->rcv_probes_mcast,
3331		   st->rcv_probes_ucast,
3332
3333		   st->periodic_gc_runs,
3334		   st->forced_gc_runs,
3335		   st->unres_discards,
3336		   st->table_fulls
3337		   );
3338
3339	return 0;
3340}
3341
3342static const struct seq_operations neigh_stat_seq_ops = {
3343	.start	= neigh_stat_seq_start,
3344	.next	= neigh_stat_seq_next,
3345	.stop	= neigh_stat_seq_stop,
3346	.show	= neigh_stat_seq_show,
3347};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3348#endif /* CONFIG_PROC_FS */
3349
3350static void __neigh_notify(struct neighbour *n, int type, int flags,
3351			   u32 pid)
 
 
 
 
 
 
 
 
3352{
3353	struct net *net = dev_net(n->dev);
3354	struct sk_buff *skb;
3355	int err = -ENOBUFS;
3356
3357	skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
3358	if (skb == NULL)
3359		goto errout;
3360
3361	err = neigh_fill_info(skb, n, pid, 0, type, flags);
3362	if (err < 0) {
3363		/* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
3364		WARN_ON(err == -EMSGSIZE);
3365		kfree_skb(skb);
3366		goto errout;
3367	}
3368	rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
3369	return;
3370errout:
3371	if (err < 0)
3372		rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
3373}
3374
 
3375void neigh_app_ns(struct neighbour *n)
3376{
3377	__neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST, 0);
3378}
3379EXPORT_SYMBOL(neigh_app_ns);
 
3380
3381#ifdef CONFIG_SYSCTL
3382static int unres_qlen_max = INT_MAX / SKB_TRUESIZE(ETH_FRAME_LEN);
3383
3384static int proc_unres_qlen(struct ctl_table *ctl, int write,
3385			   void *buffer, size_t *lenp, loff_t *ppos)
3386{
3387	int size, ret;
3388	struct ctl_table tmp = *ctl;
3389
3390	tmp.extra1 = SYSCTL_ZERO;
3391	tmp.extra2 = &unres_qlen_max;
3392	tmp.data = &size;
3393
3394	size = *(int *)ctl->data / SKB_TRUESIZE(ETH_FRAME_LEN);
3395	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
3396
3397	if (write && !ret)
3398		*(int *)ctl->data = size * SKB_TRUESIZE(ETH_FRAME_LEN);
3399	return ret;
3400}
3401
3402static struct neigh_parms *neigh_get_dev_parms_rcu(struct net_device *dev,
3403						   int family)
3404{
3405	switch (family) {
3406	case AF_INET:
3407		return __in_dev_arp_parms_get_rcu(dev);
3408	case AF_INET6:
3409		return __in6_dev_nd_parms_get_rcu(dev);
3410	}
3411	return NULL;
3412}
3413
3414static void neigh_copy_dflt_parms(struct net *net, struct neigh_parms *p,
3415				  int index)
3416{
3417	struct net_device *dev;
3418	int family = neigh_parms_family(p);
3419
3420	rcu_read_lock();
3421	for_each_netdev_rcu(net, dev) {
3422		struct neigh_parms *dst_p =
3423				neigh_get_dev_parms_rcu(dev, family);
3424
3425		if (dst_p && !test_bit(index, dst_p->data_state))
3426			dst_p->data[index] = p->data[index];
3427	}
3428	rcu_read_unlock();
3429}
3430
3431static void neigh_proc_update(struct ctl_table *ctl, int write)
3432{
3433	struct net_device *dev = ctl->extra1;
3434	struct neigh_parms *p = ctl->extra2;
3435	struct net *net = neigh_parms_net(p);
3436	int index = (int *) ctl->data - p->data;
3437
3438	if (!write)
3439		return;
3440
3441	set_bit(index, p->data_state);
3442	if (index == NEIGH_VAR_DELAY_PROBE_TIME)
3443		call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
3444	if (!dev) /* NULL dev means this is default value */
3445		neigh_copy_dflt_parms(net, p, index);
3446}
3447
3448static int neigh_proc_dointvec_zero_intmax(struct ctl_table *ctl, int write,
3449					   void *buffer, size_t *lenp,
3450					   loff_t *ppos)
3451{
3452	struct ctl_table tmp = *ctl;
3453	int ret;
3454
3455	tmp.extra1 = SYSCTL_ZERO;
3456	tmp.extra2 = SYSCTL_INT_MAX;
3457
3458	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
3459	neigh_proc_update(ctl, write);
3460	return ret;
3461}
3462
3463int neigh_proc_dointvec(struct ctl_table *ctl, int write, void *buffer,
3464			size_t *lenp, loff_t *ppos)
3465{
3466	int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
3467
3468	neigh_proc_update(ctl, write);
3469	return ret;
3470}
3471EXPORT_SYMBOL(neigh_proc_dointvec);
3472
3473int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write, void *buffer,
3474				size_t *lenp, loff_t *ppos)
3475{
3476	int ret = proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
3477
3478	neigh_proc_update(ctl, write);
3479	return ret;
3480}
3481EXPORT_SYMBOL(neigh_proc_dointvec_jiffies);
3482
3483static int neigh_proc_dointvec_userhz_jiffies(struct ctl_table *ctl, int write,
3484					      void *buffer, size_t *lenp,
3485					      loff_t *ppos)
3486{
3487	int ret = proc_dointvec_userhz_jiffies(ctl, write, buffer, lenp, ppos);
3488
3489	neigh_proc_update(ctl, write);
3490	return ret;
3491}
3492
3493int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
3494				   void *buffer, size_t *lenp, loff_t *ppos)
3495{
3496	int ret = proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
3497
3498	neigh_proc_update(ctl, write);
3499	return ret;
3500}
3501EXPORT_SYMBOL(neigh_proc_dointvec_ms_jiffies);
3502
3503static int neigh_proc_dointvec_unres_qlen(struct ctl_table *ctl, int write,
3504					  void *buffer, size_t *lenp,
3505					  loff_t *ppos)
3506{
3507	int ret = proc_unres_qlen(ctl, write, buffer, lenp, ppos);
3508
3509	neigh_proc_update(ctl, write);
3510	return ret;
3511}
3512
3513static int neigh_proc_base_reachable_time(struct ctl_table *ctl, int write,
3514					  void *buffer, size_t *lenp,
3515					  loff_t *ppos)
3516{
3517	struct neigh_parms *p = ctl->extra2;
3518	int ret;
3519
3520	if (strcmp(ctl->procname, "base_reachable_time") == 0)
3521		ret = neigh_proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
3522	else if (strcmp(ctl->procname, "base_reachable_time_ms") == 0)
3523		ret = neigh_proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
3524	else
3525		ret = -1;
3526
3527	if (write && ret == 0) {
3528		/* update reachable_time as well, otherwise, the change will
3529		 * only be effective after the next time neigh_periodic_work
3530		 * decides to recompute it
3531		 */
3532		p->reachable_time =
3533			neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
3534	}
3535	return ret;
3536}
3537
3538#define NEIGH_PARMS_DATA_OFFSET(index)	\
3539	(&((struct neigh_parms *) 0)->data[index])
3540
3541#define NEIGH_SYSCTL_ENTRY(attr, data_attr, name, mval, proc) \
3542	[NEIGH_VAR_ ## attr] = { \
3543		.procname	= name, \
3544		.data		= NEIGH_PARMS_DATA_OFFSET(NEIGH_VAR_ ## data_attr), \
3545		.maxlen		= sizeof(int), \
3546		.mode		= mval, \
3547		.proc_handler	= proc, \
3548	}
3549
3550#define NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(attr, name) \
3551	NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_zero_intmax)
3552
3553#define NEIGH_SYSCTL_JIFFIES_ENTRY(attr, name) \
3554	NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_jiffies)
3555
3556#define NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(attr, name) \
3557	NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_userhz_jiffies)
3558
3559#define NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(attr, data_attr, name) \
3560	NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_ms_jiffies)
3561
3562#define NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(attr, data_attr, name) \
3563	NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_unres_qlen)
3564
3565static struct neigh_sysctl_table {
3566	struct ctl_table_header *sysctl_header;
3567	struct ctl_table neigh_vars[NEIGH_VAR_MAX + 1];
 
3568} neigh_sysctl_template __read_mostly = {
3569	.neigh_vars = {
3570		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_PROBES, "mcast_solicit"),
3571		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(UCAST_PROBES, "ucast_solicit"),
3572		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(APP_PROBES, "app_solicit"),
3573		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_REPROBES, "mcast_resolicit"),
3574		NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(RETRANS_TIME, "retrans_time"),
3575		NEIGH_SYSCTL_JIFFIES_ENTRY(BASE_REACHABLE_TIME, "base_reachable_time"),
3576		NEIGH_SYSCTL_JIFFIES_ENTRY(DELAY_PROBE_TIME, "delay_first_probe_time"),
3577		NEIGH_SYSCTL_JIFFIES_ENTRY(GC_STALETIME, "gc_stale_time"),
3578		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(QUEUE_LEN_BYTES, "unres_qlen_bytes"),
3579		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(PROXY_QLEN, "proxy_qlen"),
3580		NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(ANYCAST_DELAY, "anycast_delay"),
3581		NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(PROXY_DELAY, "proxy_delay"),
3582		NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(LOCKTIME, "locktime"),
3583		NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(QUEUE_LEN, QUEUE_LEN_BYTES, "unres_qlen"),
3584		NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(RETRANS_TIME_MS, RETRANS_TIME, "retrans_time_ms"),
3585		NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(BASE_REACHABLE_TIME_MS, BASE_REACHABLE_TIME, "base_reachable_time_ms"),
3586		[NEIGH_VAR_GC_INTERVAL] = {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3587			.procname	= "gc_interval",
3588			.maxlen		= sizeof(int),
3589			.mode		= 0644,
3590			.proc_handler	= proc_dointvec_jiffies,
3591		},
3592		[NEIGH_VAR_GC_THRESH1] = {
3593			.procname	= "gc_thresh1",
3594			.maxlen		= sizeof(int),
3595			.mode		= 0644,
3596			.extra1		= SYSCTL_ZERO,
3597			.extra2		= SYSCTL_INT_MAX,
3598			.proc_handler	= proc_dointvec_minmax,
3599		},
3600		[NEIGH_VAR_GC_THRESH2] = {
3601			.procname	= "gc_thresh2",
3602			.maxlen		= sizeof(int),
3603			.mode		= 0644,
3604			.extra1		= SYSCTL_ZERO,
3605			.extra2		= SYSCTL_INT_MAX,
3606			.proc_handler	= proc_dointvec_minmax,
3607		},
3608		[NEIGH_VAR_GC_THRESH3] = {
3609			.procname	= "gc_thresh3",
3610			.maxlen		= sizeof(int),
3611			.mode		= 0644,
3612			.extra1		= SYSCTL_ZERO,
3613			.extra2		= SYSCTL_INT_MAX,
3614			.proc_handler	= proc_dointvec_minmax,
3615		},
3616		{},
3617	},
3618};
3619
3620int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
3621			  proc_handler *handler)
3622{
3623	int i;
3624	struct neigh_sysctl_table *t;
3625	const char *dev_name_source;
3626	char neigh_path[ sizeof("net//neigh/") + IFNAMSIZ + IFNAMSIZ ];
3627	char *p_name;
 
 
 
 
 
 
 
 
 
 
 
3628
3629	t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL);
3630	if (!t)
3631		goto err;
3632
3633	for (i = 0; i < NEIGH_VAR_GC_INTERVAL; i++) {
3634		t->neigh_vars[i].data += (long) p;
3635		t->neigh_vars[i].extra1 = dev;
3636		t->neigh_vars[i].extra2 = p;
3637	}
 
 
 
 
 
 
 
 
 
3638
3639	if (dev) {
3640		dev_name_source = dev->name;
3641		/* Terminate the table early */
3642		memset(&t->neigh_vars[NEIGH_VAR_GC_INTERVAL], 0,
3643		       sizeof(t->neigh_vars[NEIGH_VAR_GC_INTERVAL]));
3644	} else {
3645		struct neigh_table *tbl = p->tbl;
3646		dev_name_source = "default";
3647		t->neigh_vars[NEIGH_VAR_GC_INTERVAL].data = &tbl->gc_interval;
3648		t->neigh_vars[NEIGH_VAR_GC_THRESH1].data = &tbl->gc_thresh1;
3649		t->neigh_vars[NEIGH_VAR_GC_THRESH2].data = &tbl->gc_thresh2;
3650		t->neigh_vars[NEIGH_VAR_GC_THRESH3].data = &tbl->gc_thresh3;
3651	}
3652
 
3653	if (handler) {
3654		/* RetransTime */
3655		t->neigh_vars[NEIGH_VAR_RETRANS_TIME].proc_handler = handler;
 
3656		/* ReachableTime */
3657		t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler = handler;
 
3658		/* RetransTime (in milliseconds)*/
3659		t->neigh_vars[NEIGH_VAR_RETRANS_TIME_MS].proc_handler = handler;
3660		/* ReachableTime (in milliseconds) */
3661		t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler = handler;
3662	} else {
3663		/* Those handlers will update p->reachable_time after
3664		 * base_reachable_time(_ms) is set to ensure the new timer starts being
3665		 * applied after the next neighbour update instead of waiting for
3666		 * neigh_periodic_work to update its value (can be multiple minutes)
3667		 * So any handler that replaces them should do this as well
3668		 */
3669		/* ReachableTime */
3670		t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler =
3671			neigh_proc_base_reachable_time;
3672		/* ReachableTime (in milliseconds) */
3673		t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler =
3674			neigh_proc_base_reachable_time;
3675	}
3676
3677	/* Don't export sysctls to unprivileged users */
3678	if (neigh_parms_net(p)->user_ns != &init_user_ns)
3679		t->neigh_vars[0].procname = NULL;
3680
3681	switch (neigh_parms_family(p)) {
3682	case AF_INET:
3683	      p_name = "ipv4";
3684	      break;
3685	case AF_INET6:
3686	      p_name = "ipv6";
3687	      break;
3688	default:
3689	      BUG();
3690	}
3691
3692	snprintf(neigh_path, sizeof(neigh_path), "net/%s/neigh/%s",
3693		p_name, dev_name_source);
3694	t->sysctl_header =
3695		register_net_sysctl(neigh_parms_net(p), neigh_path, t->neigh_vars);
3696	if (!t->sysctl_header)
3697		goto free;
3698
3699	p->sysctl_table = t;
3700	return 0;
3701
 
 
3702free:
3703	kfree(t);
3704err:
3705	return -ENOBUFS;
3706}
3707EXPORT_SYMBOL(neigh_sysctl_register);
3708
3709void neigh_sysctl_unregister(struct neigh_parms *p)
3710{
3711	if (p->sysctl_table) {
3712		struct neigh_sysctl_table *t = p->sysctl_table;
3713		p->sysctl_table = NULL;
3714		unregister_net_sysctl_table(t->sysctl_header);
 
3715		kfree(t);
3716	}
3717}
3718EXPORT_SYMBOL(neigh_sysctl_unregister);
3719
3720#endif	/* CONFIG_SYSCTL */
3721
3722static int __init neigh_init(void)
3723{
3724	rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL, 0);
3725	rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL, 0);
3726	rtnl_register(PF_UNSPEC, RTM_GETNEIGH, neigh_get, neigh_dump_info, 0);
3727
3728	rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info,
3729		      0);
3730	rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL, 0);
3731
3732	return 0;
3733}
3734
3735subsys_initcall(neigh_init);