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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
v5.4
   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	if (neigh->parms->neigh_cleanup)
 102		neigh->parms->neigh_cleanup(neigh);
 103
 104	trace_neigh_cleanup_and_release(neigh, 0);
 105	__neigh_notify(neigh, RTM_DELNEIGH, 0, 0);
 106	call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
 107	neigh_release(neigh);
 108}
 109
 110/*
 111 * It is random distribution in the interval (1/2)*base...(3/2)*base.
 112 * It corresponds to default IPv6 settings and is not overridable,
 113 * because it is really reasonable choice.
 114 */
 115
 116unsigned long neigh_rand_reach_time(unsigned long base)
 117{
 118	return base ? (prandom_u32() % base) + (base >> 1) : 0;
 119}
 120EXPORT_SYMBOL(neigh_rand_reach_time);
 121
 122static void neigh_mark_dead(struct neighbour *n)
 123{
 124	n->dead = 1;
 125	if (!list_empty(&n->gc_list)) {
 126		list_del_init(&n->gc_list);
 127		atomic_dec(&n->tbl->gc_entries);
 128	}
 129}
 130
 131static void neigh_update_gc_list(struct neighbour *n)
 132{
 133	bool on_gc_list, exempt_from_gc;
 134
 135	write_lock_bh(&n->tbl->lock);
 136	write_lock(&n->lock);
 137
 138	/* remove from the gc list if new state is permanent or if neighbor
 139	 * is externally learned; otherwise entry should be on the gc list
 140	 */
 141	exempt_from_gc = n->nud_state & NUD_PERMANENT ||
 142			 n->flags & NTF_EXT_LEARNED;
 143	on_gc_list = !list_empty(&n->gc_list);
 144
 145	if (exempt_from_gc && on_gc_list) {
 146		list_del_init(&n->gc_list);
 147		atomic_dec(&n->tbl->gc_entries);
 148	} else if (!exempt_from_gc && !on_gc_list) {
 149		/* add entries to the tail; cleaning removes from the front */
 150		list_add_tail(&n->gc_list, &n->tbl->gc_list);
 151		atomic_inc(&n->tbl->gc_entries);
 152	}
 153
 154	write_unlock(&n->lock);
 155	write_unlock_bh(&n->tbl->lock);
 156}
 157
 158static bool neigh_update_ext_learned(struct neighbour *neigh, u32 flags,
 159				     int *notify)
 160{
 161	bool rc = false;
 162	u8 ndm_flags;
 163
 164	if (!(flags & NEIGH_UPDATE_F_ADMIN))
 165		return rc;
 166
 167	ndm_flags = (flags & NEIGH_UPDATE_F_EXT_LEARNED) ? NTF_EXT_LEARNED : 0;
 168	if ((neigh->flags ^ ndm_flags) & NTF_EXT_LEARNED) {
 169		if (ndm_flags & NTF_EXT_LEARNED)
 170			neigh->flags |= NTF_EXT_LEARNED;
 171		else
 172			neigh->flags &= ~NTF_EXT_LEARNED;
 173		rc = true;
 174		*notify = 1;
 175	}
 176
 177	return rc;
 178}
 179
 180static bool neigh_del(struct neighbour *n, struct neighbour __rcu **np,
 181		      struct neigh_table *tbl)
 182{
 183	bool retval = false;
 184
 185	write_lock(&n->lock);
 186	if (refcount_read(&n->refcnt) == 1) {
 187		struct neighbour *neigh;
 188
 189		neigh = rcu_dereference_protected(n->next,
 190						  lockdep_is_held(&tbl->lock));
 191		rcu_assign_pointer(*np, neigh);
 192		neigh_mark_dead(n);
 193		retval = true;
 194	}
 195	write_unlock(&n->lock);
 196	if (retval)
 197		neigh_cleanup_and_release(n);
 198	return retval;
 199}
 200
 201bool neigh_remove_one(struct neighbour *ndel, struct neigh_table *tbl)
 202{
 203	struct neigh_hash_table *nht;
 204	void *pkey = ndel->primary_key;
 205	u32 hash_val;
 206	struct neighbour *n;
 207	struct neighbour __rcu **np;
 208
 209	nht = rcu_dereference_protected(tbl->nht,
 210					lockdep_is_held(&tbl->lock));
 211	hash_val = tbl->hash(pkey, ndel->dev, nht->hash_rnd);
 212	hash_val = hash_val >> (32 - nht->hash_shift);
 213
 214	np = &nht->hash_buckets[hash_val];
 215	while ((n = rcu_dereference_protected(*np,
 216					      lockdep_is_held(&tbl->lock)))) {
 217		if (n == ndel)
 218			return neigh_del(n, np, tbl);
 219		np = &n->next;
 220	}
 221	return false;
 222}
 223
 224static int neigh_forced_gc(struct neigh_table *tbl)
 225{
 226	int max_clean = atomic_read(&tbl->gc_entries) - tbl->gc_thresh2;
 227	unsigned long tref = jiffies - 5 * HZ;
 228	struct neighbour *n, *tmp;
 229	int shrunk = 0;
 
 
 230
 231	NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
 232
 233	write_lock_bh(&tbl->lock);
 
 
 
 
 
 234
 235	list_for_each_entry_safe(n, tmp, &tbl->gc_list, gc_list) {
 236		if (refcount_read(&n->refcnt) == 1) {
 237			bool remove = false;
 238
 
 
 
 239			write_lock(&n->lock);
 240			if ((n->nud_state == NUD_FAILED) ||
 241			    time_after(tref, n->updated))
 242				remove = true;
 
 
 
 
 
 
 
 
 243			write_unlock(&n->lock);
 244
 245			if (remove && neigh_remove_one(n, tbl))
 246				shrunk++;
 247			if (shrunk >= max_clean)
 248				break;
 249		}
 250	}
 251
 252	tbl->last_flush = jiffies;
 253
 254	write_unlock_bh(&tbl->lock);
 255
 256	return shrunk;
 257}
 258
 259static void neigh_add_timer(struct neighbour *n, unsigned long when)
 260{
 261	neigh_hold(n);
 262	if (unlikely(mod_timer(&n->timer, when))) {
 263		printk("NEIGH: BUG, double timer add, state is %x\n",
 264		       n->nud_state);
 265		dump_stack();
 266	}
 267}
 268
 269static int neigh_del_timer(struct neighbour *n)
 270{
 271	if ((n->nud_state & NUD_IN_TIMER) &&
 272	    del_timer(&n->timer)) {
 273		neigh_release(n);
 274		return 1;
 275	}
 276	return 0;
 277}
 278
 279static void pneigh_queue_purge(struct sk_buff_head *list)
 280{
 281	struct sk_buff *skb;
 282
 283	while ((skb = skb_dequeue(list)) != NULL) {
 284		dev_put(skb->dev);
 285		kfree_skb(skb);
 286	}
 287}
 288
 289static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev,
 290			    bool skip_perm)
 291{
 292	int i;
 293	struct neigh_hash_table *nht;
 294
 295	nht = rcu_dereference_protected(tbl->nht,
 296					lockdep_is_held(&tbl->lock));
 297
 298	for (i = 0; i < (1 << nht->hash_shift); i++) {
 299		struct neighbour *n;
 300		struct neighbour __rcu **np = &nht->hash_buckets[i];
 301
 302		while ((n = rcu_dereference_protected(*np,
 303					lockdep_is_held(&tbl->lock))) != NULL) {
 304			if (dev && n->dev != dev) {
 305				np = &n->next;
 306				continue;
 307			}
 308			if (skip_perm && n->nud_state & NUD_PERMANENT) {
 309				np = &n->next;
 310				continue;
 311			}
 312			rcu_assign_pointer(*np,
 313				   rcu_dereference_protected(n->next,
 314						lockdep_is_held(&tbl->lock)));
 315			write_lock(&n->lock);
 316			neigh_del_timer(n);
 317			neigh_mark_dead(n);
 318			if (refcount_read(&n->refcnt) != 1) {
 
 319				/* The most unpleasant situation.
 320				   We must destroy neighbour entry,
 321				   but someone still uses it.
 322
 323				   The destroy will be delayed until
 324				   the last user releases us, but
 325				   we must kill timers etc. and move
 326				   it to safe state.
 327				 */
 328				__skb_queue_purge(&n->arp_queue);
 329				n->arp_queue_len_bytes = 0;
 330				n->output = neigh_blackhole;
 331				if (n->nud_state & NUD_VALID)
 332					n->nud_state = NUD_NOARP;
 333				else
 334					n->nud_state = NUD_NONE;
 335				neigh_dbg(2, "neigh %p is stray\n", n);
 336			}
 337			write_unlock(&n->lock);
 338			neigh_cleanup_and_release(n);
 339		}
 340	}
 341}
 342
 343void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
 344{
 345	write_lock_bh(&tbl->lock);
 346	neigh_flush_dev(tbl, dev, false);
 347	write_unlock_bh(&tbl->lock);
 348}
 349EXPORT_SYMBOL(neigh_changeaddr);
 350
 351static int __neigh_ifdown(struct neigh_table *tbl, struct net_device *dev,
 352			  bool skip_perm)
 353{
 354	write_lock_bh(&tbl->lock);
 355	neigh_flush_dev(tbl, dev, skip_perm);
 356	pneigh_ifdown_and_unlock(tbl, dev);
 
 357
 358	del_timer_sync(&tbl->proxy_timer);
 359	pneigh_queue_purge(&tbl->proxy_queue);
 360	return 0;
 361}
 362
 363int neigh_carrier_down(struct neigh_table *tbl, struct net_device *dev)
 364{
 365	__neigh_ifdown(tbl, dev, true);
 366	return 0;
 367}
 368EXPORT_SYMBOL(neigh_carrier_down);
 369
 370int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
 371{
 372	__neigh_ifdown(tbl, dev, false);
 373	return 0;
 374}
 375EXPORT_SYMBOL(neigh_ifdown);
 376
 377static struct neighbour *neigh_alloc(struct neigh_table *tbl,
 378				     struct net_device *dev,
 379				     bool exempt_from_gc)
 380{
 381	struct neighbour *n = NULL;
 382	unsigned long now = jiffies;
 383	int entries;
 384
 385	if (exempt_from_gc)
 386		goto do_alloc;
 387
 388	entries = atomic_inc_return(&tbl->gc_entries) - 1;
 389	if (entries >= tbl->gc_thresh3 ||
 390	    (entries >= tbl->gc_thresh2 &&
 391	     time_after(now, tbl->last_flush + 5 * HZ))) {
 392		if (!neigh_forced_gc(tbl) &&
 393		    entries >= tbl->gc_thresh3) {
 394			net_info_ratelimited("%s: neighbor table overflow!\n",
 395					     tbl->id);
 396			NEIGH_CACHE_STAT_INC(tbl, table_fulls);
 397			goto out_entries;
 398		}
 399	}
 400
 401do_alloc:
 402	n = kzalloc(tbl->entry_size + dev->neigh_priv_len, GFP_ATOMIC);
 403	if (!n)
 404		goto out_entries;
 405
 406	__skb_queue_head_init(&n->arp_queue);
 407	rwlock_init(&n->lock);
 408	seqlock_init(&n->ha_lock);
 409	n->updated	  = n->used = now;
 410	n->nud_state	  = NUD_NONE;
 411	n->output	  = neigh_blackhole;
 412	seqlock_init(&n->hh.hh_lock);
 413	n->parms	  = neigh_parms_clone(&tbl->parms);
 414	timer_setup(&n->timer, neigh_timer_handler, 0);
 415
 416	NEIGH_CACHE_STAT_INC(tbl, allocs);
 417	n->tbl		  = tbl;
 418	refcount_set(&n->refcnt, 1);
 419	n->dead		  = 1;
 420	INIT_LIST_HEAD(&n->gc_list);
 421
 422	atomic_inc(&tbl->entries);
 423out:
 424	return n;
 425
 426out_entries:
 427	if (!exempt_from_gc)
 428		atomic_dec(&tbl->gc_entries);
 429	goto out;
 430}
 431
 432static void neigh_get_hash_rnd(u32 *x)
 433{
 434	*x = get_random_u32() | 1;
 435}
 436
 437static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
 438{
 439	size_t size = (1 << shift) * sizeof(struct neighbour *);
 440	struct neigh_hash_table *ret;
 441	struct neighbour __rcu **buckets;
 442	int i;
 443
 444	ret = kmalloc(sizeof(*ret), GFP_ATOMIC);
 445	if (!ret)
 446		return NULL;
 447	if (size <= PAGE_SIZE) {
 448		buckets = kzalloc(size, GFP_ATOMIC);
 449	} else {
 450		buckets = (struct neighbour __rcu **)
 451			  __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
 452					   get_order(size));
 453		kmemleak_alloc(buckets, size, 1, GFP_ATOMIC);
 454	}
 455	if (!buckets) {
 456		kfree(ret);
 457		return NULL;
 458	}
 459	ret->hash_buckets = buckets;
 460	ret->hash_shift = shift;
 461	for (i = 0; i < NEIGH_NUM_HASH_RND; i++)
 462		neigh_get_hash_rnd(&ret->hash_rnd[i]);
 463	return ret;
 464}
 465
 466static void neigh_hash_free_rcu(struct rcu_head *head)
 467{
 468	struct neigh_hash_table *nht = container_of(head,
 469						    struct neigh_hash_table,
 470						    rcu);
 471	size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *);
 472	struct neighbour __rcu **buckets = nht->hash_buckets;
 473
 474	if (size <= PAGE_SIZE) {
 475		kfree(buckets);
 476	} else {
 477		kmemleak_free(buckets);
 478		free_pages((unsigned long)buckets, get_order(size));
 479	}
 480	kfree(nht);
 481}
 482
 483static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
 484						unsigned long new_shift)
 485{
 486	unsigned int i, hash;
 487	struct neigh_hash_table *new_nht, *old_nht;
 488
 489	NEIGH_CACHE_STAT_INC(tbl, hash_grows);
 490
 491	old_nht = rcu_dereference_protected(tbl->nht,
 492					    lockdep_is_held(&tbl->lock));
 493	new_nht = neigh_hash_alloc(new_shift);
 494	if (!new_nht)
 495		return old_nht;
 496
 497	for (i = 0; i < (1 << old_nht->hash_shift); i++) {
 498		struct neighbour *n, *next;
 499
 500		for (n = rcu_dereference_protected(old_nht->hash_buckets[i],
 501						   lockdep_is_held(&tbl->lock));
 502		     n != NULL;
 503		     n = next) {
 504			hash = tbl->hash(n->primary_key, n->dev,
 505					 new_nht->hash_rnd);
 506
 507			hash >>= (32 - new_nht->hash_shift);
 508			next = rcu_dereference_protected(n->next,
 509						lockdep_is_held(&tbl->lock));
 510
 511			rcu_assign_pointer(n->next,
 512					   rcu_dereference_protected(
 513						new_nht->hash_buckets[hash],
 514						lockdep_is_held(&tbl->lock)));
 515			rcu_assign_pointer(new_nht->hash_buckets[hash], n);
 516		}
 517	}
 518
 519	rcu_assign_pointer(tbl->nht, new_nht);
 520	call_rcu(&old_nht->rcu, neigh_hash_free_rcu);
 521	return new_nht;
 522}
 523
 524struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
 525			       struct net_device *dev)
 526{
 527	struct neighbour *n;
 
 
 
 528
 529	NEIGH_CACHE_STAT_INC(tbl, lookups);
 530
 531	rcu_read_lock_bh();
 532	n = __neigh_lookup_noref(tbl, pkey, dev);
 533	if (n) {
 534		if (!refcount_inc_not_zero(&n->refcnt))
 535			n = NULL;
 536		NEIGH_CACHE_STAT_INC(tbl, hits);
 
 
 
 
 
 
 
 537	}
 538
 539	rcu_read_unlock_bh();
 540	return n;
 541}
 542EXPORT_SYMBOL(neigh_lookup);
 543
 544struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
 545				     const void *pkey)
 546{
 547	struct neighbour *n;
 548	unsigned int key_len = tbl->key_len;
 549	u32 hash_val;
 550	struct neigh_hash_table *nht;
 551
 552	NEIGH_CACHE_STAT_INC(tbl, lookups);
 553
 554	rcu_read_lock_bh();
 555	nht = rcu_dereference_bh(tbl->nht);
 556	hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) >> (32 - nht->hash_shift);
 557
 558	for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
 559	     n != NULL;
 560	     n = rcu_dereference_bh(n->next)) {
 561		if (!memcmp(n->primary_key, pkey, key_len) &&
 562		    net_eq(dev_net(n->dev), net)) {
 563			if (!refcount_inc_not_zero(&n->refcnt))
 564				n = NULL;
 565			NEIGH_CACHE_STAT_INC(tbl, hits);
 566			break;
 567		}
 568	}
 569
 570	rcu_read_unlock_bh();
 571	return n;
 572}
 573EXPORT_SYMBOL(neigh_lookup_nodev);
 574
 575static struct neighbour *___neigh_create(struct neigh_table *tbl,
 576					 const void *pkey,
 577					 struct net_device *dev,
 578					 bool exempt_from_gc, bool want_ref)
 579{
 580	struct neighbour *n1, *rc, *n = neigh_alloc(tbl, dev, exempt_from_gc);
 581	u32 hash_val;
 582	unsigned int key_len = tbl->key_len;
 583	int error;
 
 584	struct neigh_hash_table *nht;
 585
 586	trace_neigh_create(tbl, dev, pkey, n, exempt_from_gc);
 587
 588	if (!n) {
 589		rc = ERR_PTR(-ENOBUFS);
 590		goto out;
 591	}
 592
 593	memcpy(n->primary_key, pkey, key_len);
 594	n->dev = dev;
 595	dev_hold(dev);
 596
 597	/* Protocol specific setup. */
 598	if (tbl->constructor &&	(error = tbl->constructor(n)) < 0) {
 599		rc = ERR_PTR(error);
 600		goto out_neigh_release;
 601	}
 602
 603	if (dev->netdev_ops->ndo_neigh_construct) {
 604		error = dev->netdev_ops->ndo_neigh_construct(dev, n);
 605		if (error < 0) {
 606			rc = ERR_PTR(error);
 607			goto out_neigh_release;
 608		}
 609	}
 610
 611	/* Device specific setup. */
 612	if (n->parms->neigh_setup &&
 613	    (error = n->parms->neigh_setup(n)) < 0) {
 614		rc = ERR_PTR(error);
 615		goto out_neigh_release;
 616	}
 617
 618	n->confirmed = jiffies - (NEIGH_VAR(n->parms, BASE_REACHABLE_TIME) << 1);
 619
 620	write_lock_bh(&tbl->lock);
 621	nht = rcu_dereference_protected(tbl->nht,
 622					lockdep_is_held(&tbl->lock));
 623
 624	if (atomic_read(&tbl->entries) > (1 << nht->hash_shift))
 625		nht = neigh_hash_grow(tbl, nht->hash_shift + 1);
 626
 627	hash_val = tbl->hash(n->primary_key, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
 628
 629	if (n->parms->dead) {
 630		rc = ERR_PTR(-EINVAL);
 631		goto out_tbl_unlock;
 632	}
 633
 634	for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val],
 635					    lockdep_is_held(&tbl->lock));
 636	     n1 != NULL;
 637	     n1 = rcu_dereference_protected(n1->next,
 638			lockdep_is_held(&tbl->lock))) {
 639		if (dev == n1->dev && !memcmp(n1->primary_key, n->primary_key, key_len)) {
 640			if (want_ref)
 641				neigh_hold(n1);
 642			rc = n1;
 643			goto out_tbl_unlock;
 644		}
 645	}
 646
 647	n->dead = 0;
 648	if (!exempt_from_gc)
 649		list_add_tail(&n->gc_list, &n->tbl->gc_list);
 650
 651	if (want_ref)
 652		neigh_hold(n);
 653	rcu_assign_pointer(n->next,
 654			   rcu_dereference_protected(nht->hash_buckets[hash_val],
 655						     lockdep_is_held(&tbl->lock)));
 656	rcu_assign_pointer(nht->hash_buckets[hash_val], n);
 657	write_unlock_bh(&tbl->lock);
 658	neigh_dbg(2, "neigh %p is created\n", n);
 659	rc = n;
 660out:
 661	return rc;
 662out_tbl_unlock:
 663	write_unlock_bh(&tbl->lock);
 664out_neigh_release:
 665	if (!exempt_from_gc)
 666		atomic_dec(&tbl->gc_entries);
 667	neigh_release(n);
 668	goto out;
 669}
 
 670
 671struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
 672				 struct net_device *dev, bool want_ref)
 673{
 674	return ___neigh_create(tbl, pkey, dev, false, want_ref);
 675}
 676EXPORT_SYMBOL(__neigh_create);
 677
 678static u32 pneigh_hash(const void *pkey, unsigned int key_len)
 679{
 680	u32 hash_val = *(u32 *)(pkey + key_len - 4);
 681	hash_val ^= (hash_val >> 16);
 682	hash_val ^= hash_val >> 8;
 683	hash_val ^= hash_val >> 4;
 684	hash_val &= PNEIGH_HASHMASK;
 685	return hash_val;
 686}
 687
 688static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n,
 689					      struct net *net,
 690					      const void *pkey,
 691					      unsigned int key_len,
 692					      struct net_device *dev)
 693{
 694	while (n) {
 695		if (!memcmp(n->key, pkey, key_len) &&
 696		    net_eq(pneigh_net(n), net) &&
 697		    (n->dev == dev || !n->dev))
 698			return n;
 699		n = n->next;
 700	}
 701	return NULL;
 702}
 703
 704struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
 705		struct net *net, const void *pkey, struct net_device *dev)
 706{
 707	unsigned int key_len = tbl->key_len;
 708	u32 hash_val = pneigh_hash(pkey, key_len);
 709
 710	return __pneigh_lookup_1(tbl->phash_buckets[hash_val],
 711				 net, pkey, key_len, dev);
 712}
 713EXPORT_SYMBOL_GPL(__pneigh_lookup);
 714
 715struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
 716				    struct net *net, const void *pkey,
 717				    struct net_device *dev, int creat)
 718{
 719	struct pneigh_entry *n;
 720	unsigned int key_len = tbl->key_len;
 721	u32 hash_val = pneigh_hash(pkey, key_len);
 722
 723	read_lock_bh(&tbl->lock);
 724	n = __pneigh_lookup_1(tbl->phash_buckets[hash_val],
 725			      net, pkey, key_len, dev);
 726	read_unlock_bh(&tbl->lock);
 727
 728	if (n || !creat)
 729		goto out;
 730
 731	ASSERT_RTNL();
 732
 733	n = kmalloc(sizeof(*n) + key_len, GFP_KERNEL);
 734	if (!n)
 735		goto out;
 736
 737	n->protocol = 0;
 738	write_pnet(&n->net, net);
 739	memcpy(n->key, pkey, key_len);
 740	n->dev = dev;
 741	if (dev)
 742		dev_hold(dev);
 743
 744	if (tbl->pconstructor && tbl->pconstructor(n)) {
 745		if (dev)
 746			dev_put(dev);
 
 747		kfree(n);
 748		n = NULL;
 749		goto out;
 750	}
 751
 752	write_lock_bh(&tbl->lock);
 753	n->next = tbl->phash_buckets[hash_val];
 754	tbl->phash_buckets[hash_val] = n;
 755	write_unlock_bh(&tbl->lock);
 756out:
 757	return n;
 758}
 759EXPORT_SYMBOL(pneigh_lookup);
 760
 761
 762int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
 763		  struct net_device *dev)
 764{
 765	struct pneigh_entry *n, **np;
 766	unsigned int key_len = tbl->key_len;
 767	u32 hash_val = pneigh_hash(pkey, key_len);
 768
 769	write_lock_bh(&tbl->lock);
 770	for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
 771	     np = &n->next) {
 772		if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
 773		    net_eq(pneigh_net(n), net)) {
 774			*np = n->next;
 775			write_unlock_bh(&tbl->lock);
 776			if (tbl->pdestructor)
 777				tbl->pdestructor(n);
 778			if (n->dev)
 779				dev_put(n->dev);
 
 780			kfree(n);
 781			return 0;
 782		}
 783	}
 784	write_unlock_bh(&tbl->lock);
 785	return -ENOENT;
 786}
 787
 788static int pneigh_ifdown_and_unlock(struct neigh_table *tbl,
 789				    struct net_device *dev)
 790{
 791	struct pneigh_entry *n, **np, *freelist = NULL;
 792	u32 h;
 793
 794	for (h = 0; h <= PNEIGH_HASHMASK; h++) {
 795		np = &tbl->phash_buckets[h];
 796		while ((n = *np) != NULL) {
 797			if (!dev || n->dev == dev) {
 798				*np = n->next;
 799				n->next = freelist;
 800				freelist = n;
 
 
 
 
 801				continue;
 802			}
 803			np = &n->next;
 804		}
 805	}
 806	write_unlock_bh(&tbl->lock);
 807	while ((n = freelist)) {
 808		freelist = n->next;
 809		n->next = NULL;
 810		if (tbl->pdestructor)
 811			tbl->pdestructor(n);
 812		if (n->dev)
 813			dev_put(n->dev);
 814		kfree(n);
 815	}
 816	return -ENOENT;
 817}
 818
 819static void neigh_parms_destroy(struct neigh_parms *parms);
 820
 821static inline void neigh_parms_put(struct neigh_parms *parms)
 822{
 823	if (refcount_dec_and_test(&parms->refcnt))
 824		neigh_parms_destroy(parms);
 825}
 826
 
 
 
 
 
 
 827/*
 828 *	neighbour must already be out of the table;
 829 *
 830 */
 831void neigh_destroy(struct neighbour *neigh)
 832{
 833	struct net_device *dev = neigh->dev;
 834
 835	NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
 836
 837	if (!neigh->dead) {
 838		pr_warn("Destroying alive neighbour %p\n", neigh);
 
 839		dump_stack();
 840		return;
 841	}
 842
 843	if (neigh_del_timer(neigh))
 844		pr_warn("Impossible event\n");
 845
 846	write_lock_bh(&neigh->lock);
 847	__skb_queue_purge(&neigh->arp_queue);
 848	write_unlock_bh(&neigh->lock);
 849	neigh->arp_queue_len_bytes = 0;
 850
 851	if (dev->netdev_ops->ndo_neigh_destroy)
 852		dev->netdev_ops->ndo_neigh_destroy(dev, neigh);
 853
 854	dev_put(dev);
 855	neigh_parms_put(neigh->parms);
 856
 857	neigh_dbg(2, "neigh %p is destroyed\n", neigh);
 858
 859	atomic_dec(&neigh->tbl->entries);
 860	kfree_rcu(neigh, rcu);
 861}
 862EXPORT_SYMBOL(neigh_destroy);
 863
 864/* Neighbour state is suspicious;
 865   disable fast path.
 866
 867   Called with write_locked neigh.
 868 */
 869static void neigh_suspect(struct neighbour *neigh)
 870{
 871	neigh_dbg(2, "neigh %p is suspected\n", neigh);
 872
 873	neigh->output = neigh->ops->output;
 874}
 875
 876/* Neighbour state is OK;
 877   enable fast path.
 878
 879   Called with write_locked neigh.
 880 */
 881static void neigh_connect(struct neighbour *neigh)
 882{
 883	neigh_dbg(2, "neigh %p is connected\n", neigh);
 884
 885	neigh->output = neigh->ops->connected_output;
 886}
 887
 888static void neigh_periodic_work(struct work_struct *work)
 889{
 890	struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work);
 891	struct neighbour *n;
 892	struct neighbour __rcu **np;
 893	unsigned int i;
 894	struct neigh_hash_table *nht;
 895
 896	NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
 897
 898	write_lock_bh(&tbl->lock);
 899	nht = rcu_dereference_protected(tbl->nht,
 900					lockdep_is_held(&tbl->lock));
 901
 902	/*
 903	 *	periodically recompute ReachableTime from random function
 904	 */
 905
 906	if (time_after(jiffies, tbl->last_rand + 300 * HZ)) {
 907		struct neigh_parms *p;
 908		tbl->last_rand = jiffies;
 909		list_for_each_entry(p, &tbl->parms_list, list)
 910			p->reachable_time =
 911				neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
 912	}
 913
 914	if (atomic_read(&tbl->entries) < tbl->gc_thresh1)
 915		goto out;
 916
 917	for (i = 0 ; i < (1 << nht->hash_shift); i++) {
 918		np = &nht->hash_buckets[i];
 919
 920		while ((n = rcu_dereference_protected(*np,
 921				lockdep_is_held(&tbl->lock))) != NULL) {
 922			unsigned int state;
 923
 924			write_lock(&n->lock);
 925
 926			state = n->nud_state;
 927			if ((state & (NUD_PERMANENT | NUD_IN_TIMER)) ||
 928			    (n->flags & NTF_EXT_LEARNED)) {
 929				write_unlock(&n->lock);
 930				goto next_elt;
 931			}
 932
 933			if (time_before(n->used, n->confirmed))
 934				n->used = n->confirmed;
 935
 936			if (refcount_read(&n->refcnt) == 1 &&
 937			    (state == NUD_FAILED ||
 938			     time_after(jiffies, n->used + NEIGH_VAR(n->parms, GC_STALETIME)))) {
 939				*np = n->next;
 940				neigh_mark_dead(n);
 941				write_unlock(&n->lock);
 942				neigh_cleanup_and_release(n);
 943				continue;
 944			}
 945			write_unlock(&n->lock);
 946
 947next_elt:
 948			np = &n->next;
 949		}
 950		/*
 951		 * It's fine to release lock here, even if hash table
 952		 * grows while we are preempted.
 953		 */
 954		write_unlock_bh(&tbl->lock);
 955		cond_resched();
 956		write_lock_bh(&tbl->lock);
 957		nht = rcu_dereference_protected(tbl->nht,
 958						lockdep_is_held(&tbl->lock));
 959	}
 960out:
 961	/* Cycle through all hash buckets every BASE_REACHABLE_TIME/2 ticks.
 962	 * ARP entry timeouts range from 1/2 BASE_REACHABLE_TIME to 3/2
 963	 * BASE_REACHABLE_TIME.
 964	 */
 965	queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
 966			      NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME) >> 1);
 967	write_unlock_bh(&tbl->lock);
 968}
 969
 970static __inline__ int neigh_max_probes(struct neighbour *n)
 971{
 972	struct neigh_parms *p = n->parms;
 973	return NEIGH_VAR(p, UCAST_PROBES) + NEIGH_VAR(p, APP_PROBES) +
 974	       (n->nud_state & NUD_PROBE ? NEIGH_VAR(p, MCAST_REPROBES) :
 975	        NEIGH_VAR(p, MCAST_PROBES));
 976}
 977
 978static void neigh_invalidate(struct neighbour *neigh)
 979	__releases(neigh->lock)
 980	__acquires(neigh->lock)
 981{
 982	struct sk_buff *skb;
 983
 984	NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
 985	neigh_dbg(2, "neigh %p is failed\n", neigh);
 986	neigh->updated = jiffies;
 987
 988	/* It is very thin place. report_unreachable is very complicated
 989	   routine. Particularly, it can hit the same neighbour entry!
 990
 991	   So that, we try to be accurate and avoid dead loop. --ANK
 992	 */
 993	while (neigh->nud_state == NUD_FAILED &&
 994	       (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
 995		write_unlock(&neigh->lock);
 996		neigh->ops->error_report(neigh, skb);
 997		write_lock(&neigh->lock);
 998	}
 999	__skb_queue_purge(&neigh->arp_queue);
1000	neigh->arp_queue_len_bytes = 0;
1001}
1002
1003static void neigh_probe(struct neighbour *neigh)
1004	__releases(neigh->lock)
1005{
1006	struct sk_buff *skb = skb_peek_tail(&neigh->arp_queue);
1007	/* keep skb alive even if arp_queue overflows */
1008	if (skb)
1009		skb = skb_clone(skb, GFP_ATOMIC);
1010	write_unlock(&neigh->lock);
1011	if (neigh->ops->solicit)
1012		neigh->ops->solicit(neigh, skb);
1013	atomic_inc(&neigh->probes);
1014	consume_skb(skb);
1015}
1016
1017/* Called when a timer expires for a neighbour entry. */
1018
1019static void neigh_timer_handler(struct timer_list *t)
1020{
1021	unsigned long now, next;
1022	struct neighbour *neigh = from_timer(neigh, t, timer);
1023	unsigned int state;
1024	int notify = 0;
1025
1026	write_lock(&neigh->lock);
1027
1028	state = neigh->nud_state;
1029	now = jiffies;
1030	next = now + HZ;
1031
1032	if (!(state & NUD_IN_TIMER))
 
 
 
1033		goto out;
 
1034
1035	if (state & NUD_REACHABLE) {
1036		if (time_before_eq(now,
1037				   neigh->confirmed + neigh->parms->reachable_time)) {
1038			neigh_dbg(2, "neigh %p is still alive\n", neigh);
1039			next = neigh->confirmed + neigh->parms->reachable_time;
1040		} else if (time_before_eq(now,
1041					  neigh->used +
1042					  NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
1043			neigh_dbg(2, "neigh %p is delayed\n", neigh);
1044			neigh->nud_state = NUD_DELAY;
1045			neigh->updated = jiffies;
1046			neigh_suspect(neigh);
1047			next = now + NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME);
1048		} else {
1049			neigh_dbg(2, "neigh %p is suspected\n", neigh);
1050			neigh->nud_state = NUD_STALE;
1051			neigh->updated = jiffies;
1052			neigh_suspect(neigh);
1053			notify = 1;
1054		}
1055	} else if (state & NUD_DELAY) {
1056		if (time_before_eq(now,
1057				   neigh->confirmed +
1058				   NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
1059			neigh_dbg(2, "neigh %p is now reachable\n", neigh);
1060			neigh->nud_state = NUD_REACHABLE;
1061			neigh->updated = jiffies;
1062			neigh_connect(neigh);
1063			notify = 1;
1064			next = neigh->confirmed + neigh->parms->reachable_time;
1065		} else {
1066			neigh_dbg(2, "neigh %p is probed\n", neigh);
1067			neigh->nud_state = NUD_PROBE;
1068			neigh->updated = jiffies;
1069			atomic_set(&neigh->probes, 0);
1070			notify = 1;
1071			next = now + NEIGH_VAR(neigh->parms, RETRANS_TIME);
1072		}
1073	} else {
1074		/* NUD_PROBE|NUD_INCOMPLETE */
1075		next = now + NEIGH_VAR(neigh->parms, RETRANS_TIME);
1076	}
1077
1078	if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
1079	    atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
1080		neigh->nud_state = NUD_FAILED;
1081		notify = 1;
1082		neigh_invalidate(neigh);
1083		goto out;
1084	}
1085
1086	if (neigh->nud_state & NUD_IN_TIMER) {
1087		if (time_before(next, jiffies + HZ/2))
1088			next = jiffies + HZ/2;
1089		if (!mod_timer(&neigh->timer, next))
1090			neigh_hold(neigh);
1091	}
1092	if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
1093		neigh_probe(neigh);
 
 
 
 
 
 
 
1094	} else {
1095out:
1096		write_unlock(&neigh->lock);
1097	}
1098
1099	if (notify)
1100		neigh_update_notify(neigh, 0);
1101
1102	trace_neigh_timer_handler(neigh, 0);
1103
1104	neigh_release(neigh);
1105}
1106
1107int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
1108{
1109	int rc;
1110	bool immediate_probe = false;
1111
1112	write_lock_bh(&neigh->lock);
1113
1114	rc = 0;
1115	if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
1116		goto out_unlock_bh;
1117	if (neigh->dead)
1118		goto out_dead;
1119
1120	if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
1121		if (NEIGH_VAR(neigh->parms, MCAST_PROBES) +
1122		    NEIGH_VAR(neigh->parms, APP_PROBES)) {
1123			unsigned long next, now = jiffies;
1124
1125			atomic_set(&neigh->probes,
1126				   NEIGH_VAR(neigh->parms, UCAST_PROBES));
1127			neigh_del_timer(neigh);
1128			neigh->nud_state     = NUD_INCOMPLETE;
1129			neigh->updated = now;
1130			next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
1131					 HZ/2);
1132			neigh_add_timer(neigh, next);
1133			immediate_probe = true;
1134		} else {
1135			neigh->nud_state = NUD_FAILED;
1136			neigh->updated = jiffies;
1137			write_unlock_bh(&neigh->lock);
1138
1139			kfree_skb(skb);
1140			return 1;
1141		}
1142	} else if (neigh->nud_state & NUD_STALE) {
1143		neigh_dbg(2, "neigh %p is delayed\n", neigh);
1144		neigh_del_timer(neigh);
1145		neigh->nud_state = NUD_DELAY;
1146		neigh->updated = jiffies;
1147		neigh_add_timer(neigh, jiffies +
1148				NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME));
1149	}
1150
1151	if (neigh->nud_state == NUD_INCOMPLETE) {
1152		if (skb) {
1153			while (neigh->arp_queue_len_bytes + skb->truesize >
1154			       NEIGH_VAR(neigh->parms, QUEUE_LEN_BYTES)) {
1155				struct sk_buff *buff;
1156
1157				buff = __skb_dequeue(&neigh->arp_queue);
1158				if (!buff)
1159					break;
1160				neigh->arp_queue_len_bytes -= buff->truesize;
1161				kfree_skb(buff);
1162				NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
1163			}
1164			skb_dst_force(skb);
1165			__skb_queue_tail(&neigh->arp_queue, skb);
1166			neigh->arp_queue_len_bytes += skb->truesize;
1167		}
1168		rc = 1;
1169	}
1170out_unlock_bh:
1171	if (immediate_probe)
1172		neigh_probe(neigh);
1173	else
1174		write_unlock(&neigh->lock);
1175	local_bh_enable();
1176	trace_neigh_event_send_done(neigh, rc);
1177	return rc;
1178
1179out_dead:
1180	if (neigh->nud_state & NUD_STALE)
1181		goto out_unlock_bh;
1182	write_unlock_bh(&neigh->lock);
1183	kfree_skb(skb);
1184	trace_neigh_event_send_dead(neigh, 1);
1185	return 1;
1186}
1187EXPORT_SYMBOL(__neigh_event_send);
1188
1189static void neigh_update_hhs(struct neighbour *neigh)
1190{
1191	struct hh_cache *hh;
1192	void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
1193		= NULL;
1194
1195	if (neigh->dev->header_ops)
1196		update = neigh->dev->header_ops->cache_update;
1197
1198	if (update) {
1199		hh = &neigh->hh;
1200		if (hh->hh_len) {
1201			write_seqlock_bh(&hh->hh_lock);
1202			update(hh, neigh->dev, neigh->ha);
1203			write_sequnlock_bh(&hh->hh_lock);
1204		}
1205	}
1206}
1207
1208
1209
1210/* Generic update routine.
1211   -- lladdr is new lladdr or NULL, if it is not supplied.
1212   -- new    is new state.
1213   -- flags
1214	NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
1215				if it is different.
1216	NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
1217				lladdr instead of overriding it
1218				if it is different.
 
 
1219	NEIGH_UPDATE_F_ADMIN	means that the change is administrative.
1220
1221	NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
1222				NTF_ROUTER flag.
1223	NEIGH_UPDATE_F_ISROUTER	indicates if the neighbour is known as
1224				a router.
1225
1226   Caller MUST hold reference count on the entry.
1227 */
1228
1229static int __neigh_update(struct neighbour *neigh, const u8 *lladdr,
1230			  u8 new, u32 flags, u32 nlmsg_pid,
1231			  struct netlink_ext_ack *extack)
1232{
1233	bool ext_learn_change = false;
1234	u8 old;
1235	int err;
1236	int notify = 0;
1237	struct net_device *dev;
1238	int update_isrouter = 0;
1239
1240	trace_neigh_update(neigh, lladdr, new, flags, nlmsg_pid);
1241
1242	write_lock_bh(&neigh->lock);
1243
1244	dev    = neigh->dev;
1245	old    = neigh->nud_state;
1246	err    = -EPERM;
1247
1248	if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
1249	    (old & (NUD_NOARP | NUD_PERMANENT)))
1250		goto out;
1251	if (neigh->dead) {
1252		NL_SET_ERR_MSG(extack, "Neighbor entry is now dead");
1253		goto out;
1254	}
1255
1256	ext_learn_change = neigh_update_ext_learned(neigh, flags, &notify);
1257
1258	if (!(new & NUD_VALID)) {
1259		neigh_del_timer(neigh);
1260		if (old & NUD_CONNECTED)
1261			neigh_suspect(neigh);
1262		neigh->nud_state = new;
1263		err = 0;
1264		notify = old & NUD_VALID;
1265		if ((old & (NUD_INCOMPLETE | NUD_PROBE)) &&
1266		    (new & NUD_FAILED)) {
1267			neigh_invalidate(neigh);
1268			notify = 1;
1269		}
1270		goto out;
1271	}
1272
1273	/* Compare new lladdr with cached one */
1274	if (!dev->addr_len) {
1275		/* First case: device needs no address. */
1276		lladdr = neigh->ha;
1277	} else if (lladdr) {
1278		/* The second case: if something is already cached
1279		   and a new address is proposed:
1280		   - compare new & old
1281		   - if they are different, check override flag
1282		 */
1283		if ((old & NUD_VALID) &&
1284		    !memcmp(lladdr, neigh->ha, dev->addr_len))
1285			lladdr = neigh->ha;
1286	} else {
1287		/* No address is supplied; if we know something,
1288		   use it, otherwise discard the request.
1289		 */
1290		err = -EINVAL;
1291		if (!(old & NUD_VALID)) {
1292			NL_SET_ERR_MSG(extack, "No link layer address given");
1293			goto out;
1294		}
1295		lladdr = neigh->ha;
1296	}
1297
1298	/* Update confirmed timestamp for neighbour entry after we
1299	 * received ARP packet even if it doesn't change IP to MAC binding.
1300	 */
1301	if (new & NUD_CONNECTED)
1302		neigh->confirmed = jiffies;
 
1303
1304	/* If entry was valid and address is not changed,
1305	   do not change entry state, if new one is STALE.
1306	 */
1307	err = 0;
1308	update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1309	if (old & NUD_VALID) {
1310		if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
1311			update_isrouter = 0;
1312			if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
1313			    (old & NUD_CONNECTED)) {
1314				lladdr = neigh->ha;
1315				new = NUD_STALE;
1316			} else
1317				goto out;
1318		} else {
1319			if (lladdr == neigh->ha && new == NUD_STALE &&
1320			    !(flags & NEIGH_UPDATE_F_ADMIN))
 
 
1321				new = old;
1322		}
1323	}
1324
1325	/* Update timestamp only once we know we will make a change to the
1326	 * neighbour entry. Otherwise we risk to move the locktime window with
1327	 * noop updates and ignore relevant ARP updates.
1328	 */
1329	if (new != old || lladdr != neigh->ha)
1330		neigh->updated = jiffies;
1331
1332	if (new != old) {
1333		neigh_del_timer(neigh);
1334		if (new & NUD_PROBE)
1335			atomic_set(&neigh->probes, 0);
1336		if (new & NUD_IN_TIMER)
1337			neigh_add_timer(neigh, (jiffies +
1338						((new & NUD_REACHABLE) ?
1339						 neigh->parms->reachable_time :
1340						 0)));
1341		neigh->nud_state = new;
1342		notify = 1;
1343	}
1344
1345	if (lladdr != neigh->ha) {
1346		write_seqlock(&neigh->ha_lock);
1347		memcpy(&neigh->ha, lladdr, dev->addr_len);
1348		write_sequnlock(&neigh->ha_lock);
1349		neigh_update_hhs(neigh);
1350		if (!(new & NUD_CONNECTED))
1351			neigh->confirmed = jiffies -
1352				      (NEIGH_VAR(neigh->parms, BASE_REACHABLE_TIME) << 1);
1353		notify = 1;
1354	}
1355	if (new == old)
1356		goto out;
1357	if (new & NUD_CONNECTED)
1358		neigh_connect(neigh);
1359	else
1360		neigh_suspect(neigh);
1361	if (!(old & NUD_VALID)) {
1362		struct sk_buff *skb;
1363
1364		/* Again: avoid dead loop if something went wrong */
1365
1366		while (neigh->nud_state & NUD_VALID &&
1367		       (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
1368			struct dst_entry *dst = skb_dst(skb);
1369			struct neighbour *n2, *n1 = neigh;
1370			write_unlock_bh(&neigh->lock);
1371
1372			rcu_read_lock();
1373
1374			/* Why not just use 'neigh' as-is?  The problem is that
1375			 * things such as shaper, eql, and sch_teql can end up
1376			 * using alternative, different, neigh objects to output
1377			 * the packet in the output path.  So what we need to do
1378			 * here is re-lookup the top-level neigh in the path so
1379			 * we can reinject the packet there.
1380			 */
1381			n2 = NULL;
1382			if (dst) {
1383				n2 = dst_neigh_lookup_skb(dst, skb);
1384				if (n2)
1385					n1 = n2;
1386			}
1387			n1->output(n1, skb);
1388			if (n2)
1389				neigh_release(n2);
1390			rcu_read_unlock();
1391
1392			write_lock_bh(&neigh->lock);
1393		}
1394		__skb_queue_purge(&neigh->arp_queue);
1395		neigh->arp_queue_len_bytes = 0;
1396	}
1397out:
1398	if (update_isrouter)
1399		neigh_update_is_router(neigh, flags, &notify);
 
 
 
1400	write_unlock_bh(&neigh->lock);
1401
1402	if (((new ^ old) & NUD_PERMANENT) || ext_learn_change)
1403		neigh_update_gc_list(neigh);
1404
1405	if (notify)
1406		neigh_update_notify(neigh, nlmsg_pid);
1407
1408	trace_neigh_update_done(neigh, err);
1409
1410	return err;
1411}
1412
1413int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
1414		 u32 flags, u32 nlmsg_pid)
1415{
1416	return __neigh_update(neigh, lladdr, new, flags, nlmsg_pid, NULL);
1417}
1418EXPORT_SYMBOL(neigh_update);
1419
1420/* Update the neigh to listen temporarily for probe responses, even if it is
1421 * in a NUD_FAILED state. The caller has to hold neigh->lock for writing.
1422 */
1423void __neigh_set_probe_once(struct neighbour *neigh)
1424{
1425	if (neigh->dead)
1426		return;
1427	neigh->updated = jiffies;
1428	if (!(neigh->nud_state & NUD_FAILED))
1429		return;
1430	neigh->nud_state = NUD_INCOMPLETE;
1431	atomic_set(&neigh->probes, neigh_max_probes(neigh));
1432	neigh_add_timer(neigh,
1433			jiffies + NEIGH_VAR(neigh->parms, RETRANS_TIME));
1434}
1435EXPORT_SYMBOL(__neigh_set_probe_once);
1436
1437struct neighbour *neigh_event_ns(struct neigh_table *tbl,
1438				 u8 *lladdr, void *saddr,
1439				 struct net_device *dev)
1440{
1441	struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev,
1442						 lladdr || !dev->addr_len);
1443	if (neigh)
1444		neigh_update(neigh, lladdr, NUD_STALE,
1445			     NEIGH_UPDATE_F_OVERRIDE, 0);
1446	return neigh;
1447}
1448EXPORT_SYMBOL(neigh_event_ns);
1449
1450/* called with read_lock_bh(&n->lock); */
1451static void neigh_hh_init(struct neighbour *n)
1452{
1453	struct net_device *dev = n->dev;
1454	__be16 prot = n->tbl->protocol;
1455	struct hh_cache	*hh = &n->hh;
1456
1457	write_lock_bh(&n->lock);
1458
1459	/* Only one thread can come in here and initialize the
1460	 * hh_cache entry.
1461	 */
1462	if (!hh->hh_len)
1463		dev->header_ops->cache(n, hh, prot);
1464
1465	write_unlock_bh(&n->lock);
1466}
1467
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1468/* Slow and careful. */
1469
1470int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb)
1471{
 
1472	int rc = 0;
1473
 
 
 
 
 
1474	if (!neigh_event_send(neigh, skb)) {
1475		int err;
1476		struct net_device *dev = neigh->dev;
1477		unsigned int seq;
1478
1479		if (dev->header_ops->cache && !neigh->hh.hh_len)
1480			neigh_hh_init(neigh);
1481
1482		do {
1483			__skb_pull(skb, skb_network_offset(skb));
1484			seq = read_seqbegin(&neigh->ha_lock);
1485			err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1486					      neigh->ha, NULL, skb->len);
1487		} while (read_seqretry(&neigh->ha_lock, seq));
1488
1489		if (err >= 0)
1490			rc = dev_queue_xmit(skb);
1491		else
1492			goto out_kfree_skb;
1493	}
1494out:
1495	return rc;
 
 
 
1496out_kfree_skb:
1497	rc = -EINVAL;
1498	kfree_skb(skb);
1499	goto out;
1500}
1501EXPORT_SYMBOL(neigh_resolve_output);
1502
1503/* As fast as possible without hh cache */
1504
1505int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb)
1506{
1507	struct net_device *dev = neigh->dev;
1508	unsigned int seq;
1509	int err;
1510
 
 
1511	do {
1512		__skb_pull(skb, skb_network_offset(skb));
1513		seq = read_seqbegin(&neigh->ha_lock);
1514		err = dev_hard_header(skb, dev, ntohs(skb->protocol),
1515				      neigh->ha, NULL, skb->len);
1516	} while (read_seqretry(&neigh->ha_lock, seq));
1517
1518	if (err >= 0)
1519		err = dev_queue_xmit(skb);
1520	else {
1521		err = -EINVAL;
1522		kfree_skb(skb);
1523	}
1524	return err;
1525}
1526EXPORT_SYMBOL(neigh_connected_output);
1527
1528int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb)
1529{
1530	return dev_queue_xmit(skb);
1531}
1532EXPORT_SYMBOL(neigh_direct_output);
1533
1534static void neigh_proxy_process(struct timer_list *t)
1535{
1536	struct neigh_table *tbl = from_timer(tbl, t, proxy_timer);
1537	long sched_next = 0;
1538	unsigned long now = jiffies;
1539	struct sk_buff *skb, *n;
1540
1541	spin_lock(&tbl->proxy_queue.lock);
1542
1543	skb_queue_walk_safe(&tbl->proxy_queue, skb, n) {
1544		long tdif = NEIGH_CB(skb)->sched_next - now;
1545
1546		if (tdif <= 0) {
1547			struct net_device *dev = skb->dev;
1548
1549			__skb_unlink(skb, &tbl->proxy_queue);
1550			if (tbl->proxy_redo && netif_running(dev)) {
1551				rcu_read_lock();
1552				tbl->proxy_redo(skb);
1553				rcu_read_unlock();
1554			} else {
1555				kfree_skb(skb);
1556			}
1557
1558			dev_put(dev);
1559		} else if (!sched_next || tdif < sched_next)
1560			sched_next = tdif;
1561	}
1562	del_timer(&tbl->proxy_timer);
1563	if (sched_next)
1564		mod_timer(&tbl->proxy_timer, jiffies + sched_next);
1565	spin_unlock(&tbl->proxy_queue.lock);
1566}
1567
1568void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
1569		    struct sk_buff *skb)
1570{
1571	unsigned long now = jiffies;
 
1572
1573	unsigned long sched_next = now + (prandom_u32() %
1574					  NEIGH_VAR(p, PROXY_DELAY));
1575
1576	if (tbl->proxy_queue.qlen > NEIGH_VAR(p, PROXY_QLEN)) {
1577		kfree_skb(skb);
1578		return;
1579	}
1580
1581	NEIGH_CB(skb)->sched_next = sched_next;
1582	NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
1583
1584	spin_lock(&tbl->proxy_queue.lock);
1585	if (del_timer(&tbl->proxy_timer)) {
1586		if (time_before(tbl->proxy_timer.expires, sched_next))
1587			sched_next = tbl->proxy_timer.expires;
1588	}
1589	skb_dst_drop(skb);
1590	dev_hold(skb->dev);
1591	__skb_queue_tail(&tbl->proxy_queue, skb);
1592	mod_timer(&tbl->proxy_timer, sched_next);
1593	spin_unlock(&tbl->proxy_queue.lock);
1594}
1595EXPORT_SYMBOL(pneigh_enqueue);
1596
1597static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl,
1598						      struct net *net, int ifindex)
1599{
1600	struct neigh_parms *p;
1601
1602	list_for_each_entry(p, &tbl->parms_list, list) {
1603		if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
1604		    (!p->dev && !ifindex && net_eq(net, &init_net)))
1605			return p;
1606	}
1607
1608	return NULL;
1609}
1610
1611struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
1612				      struct neigh_table *tbl)
1613{
1614	struct neigh_parms *p;
1615	struct net *net = dev_net(dev);
1616	const struct net_device_ops *ops = dev->netdev_ops;
1617
1618	p = kmemdup(&tbl->parms, sizeof(*p), GFP_KERNEL);
 
 
 
 
1619	if (p) {
1620		p->tbl		  = tbl;
1621		refcount_set(&p->refcnt, 1);
1622		p->reachable_time =
1623				neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
1624		dev_hold(dev);
1625		p->dev = dev;
1626		write_pnet(&p->net, net);
1627		p->sysctl_table = NULL;
1628
1629		if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) {
1630			dev_put(dev);
1631			kfree(p);
1632			return NULL;
1633		}
1634
 
 
 
 
1635		write_lock_bh(&tbl->lock);
1636		list_add(&p->list, &tbl->parms.list);
 
1637		write_unlock_bh(&tbl->lock);
1638
1639		neigh_parms_data_state_cleanall(p);
1640	}
1641	return p;
1642}
1643EXPORT_SYMBOL(neigh_parms_alloc);
1644
1645static void neigh_rcu_free_parms(struct rcu_head *head)
1646{
1647	struct neigh_parms *parms =
1648		container_of(head, struct neigh_parms, rcu_head);
1649
1650	neigh_parms_put(parms);
1651}
1652
1653void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
1654{
 
 
1655	if (!parms || parms == &tbl->parms)
1656		return;
1657	write_lock_bh(&tbl->lock);
1658	list_del(&parms->list);
1659	parms->dead = 1;
 
 
 
 
 
 
 
 
 
1660	write_unlock_bh(&tbl->lock);
1661	if (parms->dev)
1662		dev_put(parms->dev);
1663	call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
1664}
1665EXPORT_SYMBOL(neigh_parms_release);
1666
1667static void neigh_parms_destroy(struct neigh_parms *parms)
1668{
 
1669	kfree(parms);
1670}
1671
1672static struct lock_class_key neigh_table_proxy_queue_class;
1673
1674static struct neigh_table *neigh_tables[NEIGH_NR_TABLES] __read_mostly;
1675
1676void neigh_table_init(int index, struct neigh_table *tbl)
1677{
1678	unsigned long now = jiffies;
1679	unsigned long phsize;
1680
1681	INIT_LIST_HEAD(&tbl->parms_list);
1682	INIT_LIST_HEAD(&tbl->gc_list);
1683	list_add(&tbl->parms.list, &tbl->parms_list);
1684	write_pnet(&tbl->parms.net, &init_net);
1685	refcount_set(&tbl->parms.refcnt, 1);
1686	tbl->parms.reachable_time =
1687			  neigh_rand_reach_time(NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME));
1688
 
 
 
 
 
1689	tbl->stats = alloc_percpu(struct neigh_statistics);
1690	if (!tbl->stats)
1691		panic("cannot create neighbour cache statistics");
1692
1693#ifdef CONFIG_PROC_FS
1694	if (!proc_create_seq_data(tbl->id, 0, init_net.proc_net_stat,
1695			      &neigh_stat_seq_ops, tbl))
1696		panic("cannot create neighbour proc dir entry");
1697#endif
1698
1699	RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3));
1700
1701	phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
1702	tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
1703
1704	if (!tbl->nht || !tbl->phash_buckets)
1705		panic("cannot allocate neighbour cache hashes");
1706
1707	if (!tbl->entry_size)
1708		tbl->entry_size = ALIGN(offsetof(struct neighbour, primary_key) +
1709					tbl->key_len, NEIGH_PRIV_ALIGN);
1710	else
1711		WARN_ON(tbl->entry_size % NEIGH_PRIV_ALIGN);
1712
1713	rwlock_init(&tbl->lock);
1714	INIT_DEFERRABLE_WORK(&tbl->gc_work, neigh_periodic_work);
1715	queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
1716			tbl->parms.reachable_time);
1717	timer_setup(&tbl->proxy_timer, neigh_proxy_process, 0);
1718	skb_queue_head_init_class(&tbl->proxy_queue,
1719			&neigh_table_proxy_queue_class);
1720
1721	tbl->last_flush = now;
1722	tbl->last_rand	= now + tbl->parms.reachable_time * 20;
 
 
 
 
 
 
1723
1724	neigh_tables[index] = tbl;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1725}
1726EXPORT_SYMBOL(neigh_table_init);
1727
1728int neigh_table_clear(int index, struct neigh_table *tbl)
1729{
1730	neigh_tables[index] = NULL;
 
1731	/* It is not clean... Fix it to unload IPv6 module safely */
1732	cancel_delayed_work_sync(&tbl->gc_work);
1733	del_timer_sync(&tbl->proxy_timer);
1734	pneigh_queue_purge(&tbl->proxy_queue);
1735	neigh_ifdown(tbl, NULL);
1736	if (atomic_read(&tbl->entries))
1737		pr_crit("neighbour leakage\n");
 
 
 
 
 
 
 
 
1738
1739	call_rcu(&rcu_dereference_protected(tbl->nht, 1)->rcu,
1740		 neigh_hash_free_rcu);
1741	tbl->nht = NULL;
1742
1743	kfree(tbl->phash_buckets);
1744	tbl->phash_buckets = NULL;
1745
1746	remove_proc_entry(tbl->id, init_net.proc_net_stat);
1747
1748	free_percpu(tbl->stats);
1749	tbl->stats = NULL;
1750
 
 
 
1751	return 0;
1752}
1753EXPORT_SYMBOL(neigh_table_clear);
1754
1755static struct neigh_table *neigh_find_table(int family)
1756{
1757	struct neigh_table *tbl = NULL;
1758
1759	switch (family) {
1760	case AF_INET:
1761		tbl = neigh_tables[NEIGH_ARP_TABLE];
1762		break;
1763	case AF_INET6:
1764		tbl = neigh_tables[NEIGH_ND_TABLE];
1765		break;
1766	case AF_DECnet:
1767		tbl = neigh_tables[NEIGH_DN_TABLE];
1768		break;
1769	}
1770
1771	return tbl;
1772}
1773
1774const struct nla_policy nda_policy[NDA_MAX+1] = {
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};
1786
1787static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh,
1788			struct netlink_ext_ack *extack)
1789{
1790	struct net *net = sock_net(skb->sk);
1791	struct ndmsg *ndm;
1792	struct nlattr *dst_attr;
1793	struct neigh_table *tbl;
1794	struct neighbour *neigh;
1795	struct net_device *dev = NULL;
1796	int err = -EINVAL;
1797
1798	ASSERT_RTNL();
1799	if (nlmsg_len(nlh) < sizeof(*ndm))
1800		goto out;
1801
1802	dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
1803	if (!dst_attr) {
1804		NL_SET_ERR_MSG(extack, "Network address not specified");
1805		goto out;
1806	}
1807
1808	ndm = nlmsg_data(nlh);
1809	if (ndm->ndm_ifindex) {
1810		dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1811		if (dev == NULL) {
1812			err = -ENODEV;
1813			goto out;
1814		}
1815	}
1816
1817	tbl = neigh_find_table(ndm->ndm_family);
1818	if (tbl == NULL)
1819		return -EAFNOSUPPORT;
 
 
 
 
 
 
 
1820
1821	if (nla_len(dst_attr) < (int)tbl->key_len) {
1822		NL_SET_ERR_MSG(extack, "Invalid network address");
1823		goto out;
1824	}
1825
1826	if (ndm->ndm_flags & NTF_PROXY) {
1827		err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
1828		goto out;
1829	}
1830
1831	if (dev == NULL)
1832		goto out;
 
 
 
1833
1834	neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
1835	if (neigh == NULL) {
1836		err = -ENOENT;
 
1837		goto out;
1838	}
1839
1840	err = __neigh_update(neigh, NULL, NUD_FAILED,
1841			     NEIGH_UPDATE_F_OVERRIDE | NEIGH_UPDATE_F_ADMIN,
1842			     NETLINK_CB(skb).portid, extack);
1843	write_lock_bh(&tbl->lock);
1844	neigh_release(neigh);
1845	neigh_remove_one(neigh, tbl);
1846	write_unlock_bh(&tbl->lock);
1847
1848out:
1849	return err;
1850}
1851
1852static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh,
1853		     struct netlink_ext_ack *extack)
1854{
1855	int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE |
1856		NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
1857	struct net *net = sock_net(skb->sk);
1858	struct ndmsg *ndm;
1859	struct nlattr *tb[NDA_MAX+1];
1860	struct neigh_table *tbl;
1861	struct net_device *dev = NULL;
1862	struct neighbour *neigh;
1863	void *dst, *lladdr;
1864	u8 protocol = 0;
1865	int err;
1866
1867	ASSERT_RTNL();
1868	err = nlmsg_parse_deprecated(nlh, sizeof(*ndm), tb, NDA_MAX,
1869				     nda_policy, extack);
1870	if (err < 0)
1871		goto out;
1872
1873	err = -EINVAL;
1874	if (!tb[NDA_DST]) {
1875		NL_SET_ERR_MSG(extack, "Network address not specified");
1876		goto out;
1877	}
1878
1879	ndm = nlmsg_data(nlh);
1880	if (ndm->ndm_ifindex) {
1881		dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1882		if (dev == NULL) {
1883			err = -ENODEV;
1884			goto out;
1885		}
1886
1887		if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len) {
1888			NL_SET_ERR_MSG(extack, "Invalid link address");
1889			goto out;
1890		}
1891	}
1892
1893	tbl = neigh_find_table(ndm->ndm_family);
1894	if (tbl == NULL)
1895		return -EAFNOSUPPORT;
 
 
1896
1897	if (nla_len(tb[NDA_DST]) < (int)tbl->key_len) {
1898		NL_SET_ERR_MSG(extack, "Invalid network address");
1899		goto out;
1900	}
1901
1902	dst = nla_data(tb[NDA_DST]);
1903	lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
 
 
1904
1905	if (tb[NDA_PROTOCOL])
1906		protocol = nla_get_u8(tb[NDA_PROTOCOL]);
1907
1908	if (ndm->ndm_flags & NTF_PROXY) {
1909		struct pneigh_entry *pn;
1910
1911		err = -ENOBUFS;
1912		pn = pneigh_lookup(tbl, net, dst, dev, 1);
1913		if (pn) {
1914			pn->flags = ndm->ndm_flags;
1915			if (protocol)
1916				pn->protocol = protocol;
1917			err = 0;
1918		}
1919		goto out;
1920	}
1921
1922	if (!dev) {
1923		NL_SET_ERR_MSG(extack, "Device not specified");
1924		goto out;
1925	}
1926
1927	if (tbl->allow_add && !tbl->allow_add(dev, extack)) {
1928		err = -EINVAL;
1929		goto out;
1930	}
 
 
1931
1932	neigh = neigh_lookup(tbl, dst, dev);
1933	if (neigh == NULL) {
1934		bool exempt_from_gc;
 
 
 
 
 
 
 
 
1935
1936		if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
1937			err = -ENOENT;
1938			goto out;
1939		}
1940
1941		exempt_from_gc = ndm->ndm_state & NUD_PERMANENT ||
1942				 ndm->ndm_flags & NTF_EXT_LEARNED;
1943		neigh = ___neigh_create(tbl, dst, dev, exempt_from_gc, true);
1944		if (IS_ERR(neigh)) {
1945			err = PTR_ERR(neigh);
1946			goto out;
1947		}
1948	} else {
1949		if (nlh->nlmsg_flags & NLM_F_EXCL) {
1950			err = -EEXIST;
1951			neigh_release(neigh);
1952			goto out;
1953		}
1954
1955		if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
1956			flags &= ~(NEIGH_UPDATE_F_OVERRIDE |
1957				   NEIGH_UPDATE_F_OVERRIDE_ISROUTER);
1958	}
1959
1960	if (ndm->ndm_flags & NTF_EXT_LEARNED)
1961		flags |= NEIGH_UPDATE_F_EXT_LEARNED;
1962
1963	if (ndm->ndm_flags & NTF_ROUTER)
1964		flags |= NEIGH_UPDATE_F_ISROUTER;
1965
1966	if (ndm->ndm_flags & NTF_USE) {
1967		neigh_event_send(neigh, NULL);
1968		err = 0;
1969	} else
1970		err = __neigh_update(neigh, lladdr, ndm->ndm_state, flags,
1971				     NETLINK_CB(skb).portid, extack);
1972
1973	if (protocol)
1974		neigh->protocol = protocol;
1975
1976	neigh_release(neigh);
1977
1978out:
1979	return err;
1980}
1981
1982static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
1983{
1984	struct nlattr *nest;
1985
1986	nest = nla_nest_start_noflag(skb, NDTA_PARMS);
1987	if (nest == NULL)
1988		return -ENOBUFS;
1989
1990	if ((parms->dev &&
1991	     nla_put_u32(skb, NDTPA_IFINDEX, parms->dev->ifindex)) ||
1992	    nla_put_u32(skb, NDTPA_REFCNT, refcount_read(&parms->refcnt)) ||
1993	    nla_put_u32(skb, NDTPA_QUEUE_LENBYTES,
1994			NEIGH_VAR(parms, QUEUE_LEN_BYTES)) ||
1995	    /* approximative value for deprecated QUEUE_LEN (in packets) */
1996	    nla_put_u32(skb, NDTPA_QUEUE_LEN,
1997			NEIGH_VAR(parms, QUEUE_LEN_BYTES) / SKB_TRUESIZE(ETH_FRAME_LEN)) ||
1998	    nla_put_u32(skb, NDTPA_PROXY_QLEN, NEIGH_VAR(parms, PROXY_QLEN)) ||
1999	    nla_put_u32(skb, NDTPA_APP_PROBES, NEIGH_VAR(parms, APP_PROBES)) ||
2000	    nla_put_u32(skb, NDTPA_UCAST_PROBES,
2001			NEIGH_VAR(parms, UCAST_PROBES)) ||
2002	    nla_put_u32(skb, NDTPA_MCAST_PROBES,
2003			NEIGH_VAR(parms, MCAST_PROBES)) ||
2004	    nla_put_u32(skb, NDTPA_MCAST_REPROBES,
2005			NEIGH_VAR(parms, MCAST_REPROBES)) ||
2006	    nla_put_msecs(skb, NDTPA_REACHABLE_TIME, parms->reachable_time,
2007			  NDTPA_PAD) ||
2008	    nla_put_msecs(skb, NDTPA_BASE_REACHABLE_TIME,
2009			  NEIGH_VAR(parms, BASE_REACHABLE_TIME), NDTPA_PAD) ||
2010	    nla_put_msecs(skb, NDTPA_GC_STALETIME,
2011			  NEIGH_VAR(parms, GC_STALETIME), NDTPA_PAD) ||
2012	    nla_put_msecs(skb, NDTPA_DELAY_PROBE_TIME,
2013			  NEIGH_VAR(parms, DELAY_PROBE_TIME), NDTPA_PAD) ||
2014	    nla_put_msecs(skb, NDTPA_RETRANS_TIME,
2015			  NEIGH_VAR(parms, RETRANS_TIME), NDTPA_PAD) ||
2016	    nla_put_msecs(skb, NDTPA_ANYCAST_DELAY,
2017			  NEIGH_VAR(parms, ANYCAST_DELAY), NDTPA_PAD) ||
2018	    nla_put_msecs(skb, NDTPA_PROXY_DELAY,
2019			  NEIGH_VAR(parms, PROXY_DELAY), NDTPA_PAD) ||
2020	    nla_put_msecs(skb, NDTPA_LOCKTIME,
2021			  NEIGH_VAR(parms, LOCKTIME), NDTPA_PAD))
2022		goto nla_put_failure;
2023	return nla_nest_end(skb, nest);
2024
2025nla_put_failure:
2026	nla_nest_cancel(skb, nest);
2027	return -EMSGSIZE;
2028}
2029
2030static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
2031			      u32 pid, u32 seq, int type, int flags)
2032{
2033	struct nlmsghdr *nlh;
2034	struct ndtmsg *ndtmsg;
2035
2036	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
2037	if (nlh == NULL)
2038		return -EMSGSIZE;
2039
2040	ndtmsg = nlmsg_data(nlh);
2041
2042	read_lock_bh(&tbl->lock);
2043	ndtmsg->ndtm_family = tbl->family;
2044	ndtmsg->ndtm_pad1   = 0;
2045	ndtmsg->ndtm_pad2   = 0;
2046
2047	if (nla_put_string(skb, NDTA_NAME, tbl->id) ||
2048	    nla_put_msecs(skb, NDTA_GC_INTERVAL, tbl->gc_interval, NDTA_PAD) ||
2049	    nla_put_u32(skb, NDTA_THRESH1, tbl->gc_thresh1) ||
2050	    nla_put_u32(skb, NDTA_THRESH2, tbl->gc_thresh2) ||
2051	    nla_put_u32(skb, NDTA_THRESH3, tbl->gc_thresh3))
2052		goto nla_put_failure;
2053	{
2054		unsigned long now = jiffies;
2055		unsigned int flush_delta = now - tbl->last_flush;
2056		unsigned int rand_delta = now - tbl->last_rand;
2057		struct neigh_hash_table *nht;
2058		struct ndt_config ndc = {
2059			.ndtc_key_len		= tbl->key_len,
2060			.ndtc_entry_size	= tbl->entry_size,
2061			.ndtc_entries		= atomic_read(&tbl->entries),
2062			.ndtc_last_flush	= jiffies_to_msecs(flush_delta),
2063			.ndtc_last_rand		= jiffies_to_msecs(rand_delta),
2064			.ndtc_proxy_qlen	= tbl->proxy_queue.qlen,
2065		};
2066
2067		rcu_read_lock_bh();
2068		nht = rcu_dereference_bh(tbl->nht);
2069		ndc.ndtc_hash_rnd = nht->hash_rnd[0];
2070		ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
2071		rcu_read_unlock_bh();
2072
2073		if (nla_put(skb, NDTA_CONFIG, sizeof(ndc), &ndc))
2074			goto nla_put_failure;
2075	}
2076
2077	{
2078		int cpu;
2079		struct ndt_stats ndst;
2080
2081		memset(&ndst, 0, sizeof(ndst));
2082
2083		for_each_possible_cpu(cpu) {
2084			struct neigh_statistics	*st;
2085
2086			st = per_cpu_ptr(tbl->stats, cpu);
2087			ndst.ndts_allocs		+= st->allocs;
2088			ndst.ndts_destroys		+= st->destroys;
2089			ndst.ndts_hash_grows		+= st->hash_grows;
2090			ndst.ndts_res_failed		+= st->res_failed;
2091			ndst.ndts_lookups		+= st->lookups;
2092			ndst.ndts_hits			+= st->hits;
2093			ndst.ndts_rcv_probes_mcast	+= st->rcv_probes_mcast;
2094			ndst.ndts_rcv_probes_ucast	+= st->rcv_probes_ucast;
2095			ndst.ndts_periodic_gc_runs	+= st->periodic_gc_runs;
2096			ndst.ndts_forced_gc_runs	+= st->forced_gc_runs;
2097			ndst.ndts_table_fulls		+= st->table_fulls;
2098		}
2099
2100		if (nla_put_64bit(skb, NDTA_STATS, sizeof(ndst), &ndst,
2101				  NDTA_PAD))
2102			goto nla_put_failure;
2103	}
2104
2105	BUG_ON(tbl->parms.dev);
2106	if (neightbl_fill_parms(skb, &tbl->parms) < 0)
2107		goto nla_put_failure;
2108
2109	read_unlock_bh(&tbl->lock);
2110	nlmsg_end(skb, nlh);
2111	return 0;
2112
2113nla_put_failure:
2114	read_unlock_bh(&tbl->lock);
2115	nlmsg_cancel(skb, nlh);
2116	return -EMSGSIZE;
2117}
2118
2119static int neightbl_fill_param_info(struct sk_buff *skb,
2120				    struct neigh_table *tbl,
2121				    struct neigh_parms *parms,
2122				    u32 pid, u32 seq, int type,
2123				    unsigned int flags)
2124{
2125	struct ndtmsg *ndtmsg;
2126	struct nlmsghdr *nlh;
2127
2128	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
2129	if (nlh == NULL)
2130		return -EMSGSIZE;
2131
2132	ndtmsg = nlmsg_data(nlh);
2133
2134	read_lock_bh(&tbl->lock);
2135	ndtmsg->ndtm_family = tbl->family;
2136	ndtmsg->ndtm_pad1   = 0;
2137	ndtmsg->ndtm_pad2   = 0;
2138
2139	if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
2140	    neightbl_fill_parms(skb, parms) < 0)
2141		goto errout;
2142
2143	read_unlock_bh(&tbl->lock);
2144	nlmsg_end(skb, nlh);
2145	return 0;
2146errout:
2147	read_unlock_bh(&tbl->lock);
2148	nlmsg_cancel(skb, nlh);
2149	return -EMSGSIZE;
2150}
2151
2152static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
2153	[NDTA_NAME]		= { .type = NLA_STRING },
2154	[NDTA_THRESH1]		= { .type = NLA_U32 },
2155	[NDTA_THRESH2]		= { .type = NLA_U32 },
2156	[NDTA_THRESH3]		= { .type = NLA_U32 },
2157	[NDTA_GC_INTERVAL]	= { .type = NLA_U64 },
2158	[NDTA_PARMS]		= { .type = NLA_NESTED },
2159};
2160
2161static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
2162	[NDTPA_IFINDEX]			= { .type = NLA_U32 },
2163	[NDTPA_QUEUE_LEN]		= { .type = NLA_U32 },
2164	[NDTPA_PROXY_QLEN]		= { .type = NLA_U32 },
2165	[NDTPA_APP_PROBES]		= { .type = NLA_U32 },
2166	[NDTPA_UCAST_PROBES]		= { .type = NLA_U32 },
2167	[NDTPA_MCAST_PROBES]		= { .type = NLA_U32 },
2168	[NDTPA_MCAST_REPROBES]		= { .type = NLA_U32 },
2169	[NDTPA_BASE_REACHABLE_TIME]	= { .type = NLA_U64 },
2170	[NDTPA_GC_STALETIME]		= { .type = NLA_U64 },
2171	[NDTPA_DELAY_PROBE_TIME]	= { .type = NLA_U64 },
2172	[NDTPA_RETRANS_TIME]		= { .type = NLA_U64 },
2173	[NDTPA_ANYCAST_DELAY]		= { .type = NLA_U64 },
2174	[NDTPA_PROXY_DELAY]		= { .type = NLA_U64 },
2175	[NDTPA_LOCKTIME]		= { .type = NLA_U64 },
2176};
2177
2178static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh,
2179			struct netlink_ext_ack *extack)
2180{
2181	struct net *net = sock_net(skb->sk);
2182	struct neigh_table *tbl;
2183	struct ndtmsg *ndtmsg;
2184	struct nlattr *tb[NDTA_MAX+1];
2185	bool found = false;
2186	int err, tidx;
2187
2188	err = nlmsg_parse_deprecated(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
2189				     nl_neightbl_policy, extack);
2190	if (err < 0)
2191		goto errout;
2192
2193	if (tb[NDTA_NAME] == NULL) {
2194		err = -EINVAL;
2195		goto errout;
2196	}
2197
2198	ndtmsg = nlmsg_data(nlh);
2199
2200	for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
2201		tbl = neigh_tables[tidx];
2202		if (!tbl)
2203			continue;
2204		if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
2205			continue;
2206		if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0) {
2207			found = true;
2208			break;
2209		}
2210	}
2211
2212	if (!found)
2213		return -ENOENT;
 
 
2214
2215	/*
2216	 * We acquire tbl->lock to be nice to the periodic timers and
2217	 * make sure they always see a consistent set of values.
2218	 */
2219	write_lock_bh(&tbl->lock);
2220
2221	if (tb[NDTA_PARMS]) {
2222		struct nlattr *tbp[NDTPA_MAX+1];
2223		struct neigh_parms *p;
2224		int i, ifindex = 0;
2225
2226		err = nla_parse_nested_deprecated(tbp, NDTPA_MAX,
2227						  tb[NDTA_PARMS],
2228						  nl_ntbl_parm_policy, extack);
2229		if (err < 0)
2230			goto errout_tbl_lock;
2231
2232		if (tbp[NDTPA_IFINDEX])
2233			ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
2234
2235		p = lookup_neigh_parms(tbl, net, ifindex);
2236		if (p == NULL) {
2237			err = -ENOENT;
2238			goto errout_tbl_lock;
2239		}
2240
2241		for (i = 1; i <= NDTPA_MAX; i++) {
2242			if (tbp[i] == NULL)
2243				continue;
2244
2245			switch (i) {
2246			case NDTPA_QUEUE_LEN:
2247				NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2248					      nla_get_u32(tbp[i]) *
2249					      SKB_TRUESIZE(ETH_FRAME_LEN));
2250				break;
2251			case NDTPA_QUEUE_LENBYTES:
2252				NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
2253					      nla_get_u32(tbp[i]));
2254				break;
2255			case NDTPA_PROXY_QLEN:
2256				NEIGH_VAR_SET(p, PROXY_QLEN,
2257					      nla_get_u32(tbp[i]));
2258				break;
2259			case NDTPA_APP_PROBES:
2260				NEIGH_VAR_SET(p, APP_PROBES,
2261					      nla_get_u32(tbp[i]));
2262				break;
2263			case NDTPA_UCAST_PROBES:
2264				NEIGH_VAR_SET(p, UCAST_PROBES,
2265					      nla_get_u32(tbp[i]));
2266				break;
2267			case NDTPA_MCAST_PROBES:
2268				NEIGH_VAR_SET(p, MCAST_PROBES,
2269					      nla_get_u32(tbp[i]));
2270				break;
2271			case NDTPA_MCAST_REPROBES:
2272				NEIGH_VAR_SET(p, MCAST_REPROBES,
2273					      nla_get_u32(tbp[i]));
2274				break;
2275			case NDTPA_BASE_REACHABLE_TIME:
2276				NEIGH_VAR_SET(p, BASE_REACHABLE_TIME,
2277					      nla_get_msecs(tbp[i]));
2278				/* update reachable_time as well, otherwise, the change will
2279				 * only be effective after the next time neigh_periodic_work
2280				 * decides to recompute it (can be multiple minutes)
2281				 */
2282				p->reachable_time =
2283					neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
2284				break;
2285			case NDTPA_GC_STALETIME:
2286				NEIGH_VAR_SET(p, GC_STALETIME,
2287					      nla_get_msecs(tbp[i]));
2288				break;
2289			case NDTPA_DELAY_PROBE_TIME:
2290				NEIGH_VAR_SET(p, DELAY_PROBE_TIME,
2291					      nla_get_msecs(tbp[i]));
2292				call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
2293				break;
2294			case NDTPA_RETRANS_TIME:
2295				NEIGH_VAR_SET(p, RETRANS_TIME,
2296					      nla_get_msecs(tbp[i]));
2297				break;
2298			case NDTPA_ANYCAST_DELAY:
2299				NEIGH_VAR_SET(p, ANYCAST_DELAY,
2300					      nla_get_msecs(tbp[i]));
2301				break;
2302			case NDTPA_PROXY_DELAY:
2303				NEIGH_VAR_SET(p, PROXY_DELAY,
2304					      nla_get_msecs(tbp[i]));
2305				break;
2306			case NDTPA_LOCKTIME:
2307				NEIGH_VAR_SET(p, LOCKTIME,
2308					      nla_get_msecs(tbp[i]));
2309				break;
2310			}
2311		}
2312	}
2313
2314	err = -ENOENT;
2315	if ((tb[NDTA_THRESH1] || tb[NDTA_THRESH2] ||
2316	     tb[NDTA_THRESH3] || tb[NDTA_GC_INTERVAL]) &&
2317	    !net_eq(net, &init_net))
2318		goto errout_tbl_lock;
2319
2320	if (tb[NDTA_THRESH1])
2321		tbl->gc_thresh1 = nla_get_u32(tb[NDTA_THRESH1]);
2322
2323	if (tb[NDTA_THRESH2])
2324		tbl->gc_thresh2 = nla_get_u32(tb[NDTA_THRESH2]);
2325
2326	if (tb[NDTA_THRESH3])
2327		tbl->gc_thresh3 = nla_get_u32(tb[NDTA_THRESH3]);
2328
2329	if (tb[NDTA_GC_INTERVAL])
2330		tbl->gc_interval = nla_get_msecs(tb[NDTA_GC_INTERVAL]);
2331
2332	err = 0;
2333
2334errout_tbl_lock:
2335	write_unlock_bh(&tbl->lock);
 
 
2336errout:
2337	return err;
2338}
2339
2340static int neightbl_valid_dump_info(const struct nlmsghdr *nlh,
2341				    struct netlink_ext_ack *extack)
2342{
2343	struct ndtmsg *ndtm;
2344
2345	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndtm))) {
2346		NL_SET_ERR_MSG(extack, "Invalid header for neighbor table dump request");
2347		return -EINVAL;
2348	}
2349
2350	ndtm = nlmsg_data(nlh);
2351	if (ndtm->ndtm_pad1  || ndtm->ndtm_pad2) {
2352		NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor table dump request");
2353		return -EINVAL;
2354	}
2355
2356	if (nlmsg_attrlen(nlh, sizeof(*ndtm))) {
2357		NL_SET_ERR_MSG(extack, "Invalid data after header in neighbor table dump request");
2358		return -EINVAL;
2359	}
2360
2361	return 0;
2362}
2363
2364static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2365{
2366	const struct nlmsghdr *nlh = cb->nlh;
2367	struct net *net = sock_net(skb->sk);
2368	int family, tidx, nidx = 0;
2369	int tbl_skip = cb->args[0];
2370	int neigh_skip = cb->args[1];
2371	struct neigh_table *tbl;
2372
2373	if (cb->strict_check) {
2374		int err = neightbl_valid_dump_info(nlh, cb->extack);
2375
2376		if (err < 0)
2377			return err;
2378	}
2379
2380	family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family;
2381
2382	for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
2383		struct neigh_parms *p;
2384
2385		tbl = neigh_tables[tidx];
2386		if (!tbl)
2387			continue;
2388
2389		if (tidx < tbl_skip || (family && tbl->family != family))
2390			continue;
2391
2392		if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).portid,
2393				       nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
2394				       NLM_F_MULTI) < 0)
2395			break;
2396
2397		nidx = 0;
2398		p = list_next_entry(&tbl->parms, list);
2399		list_for_each_entry_from(p, &tbl->parms_list, list) {
2400			if (!net_eq(neigh_parms_net(p), net))
2401				continue;
2402
2403			if (nidx < neigh_skip)
2404				goto next;
2405
2406			if (neightbl_fill_param_info(skb, tbl, p,
2407						     NETLINK_CB(cb->skb).portid,
2408						     nlh->nlmsg_seq,
2409						     RTM_NEWNEIGHTBL,
2410						     NLM_F_MULTI) < 0)
2411				goto out;
2412		next:
2413			nidx++;
2414		}
2415
2416		neigh_skip = 0;
2417	}
2418out:
 
2419	cb->args[0] = tidx;
2420	cb->args[1] = nidx;
2421
2422	return skb->len;
2423}
2424
2425static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
2426			   u32 pid, u32 seq, int type, unsigned int flags)
2427{
2428	unsigned long now = jiffies;
2429	struct nda_cacheinfo ci;
2430	struct nlmsghdr *nlh;
2431	struct ndmsg *ndm;
2432
2433	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2434	if (nlh == NULL)
2435		return -EMSGSIZE;
2436
2437	ndm = nlmsg_data(nlh);
2438	ndm->ndm_family	 = neigh->ops->family;
2439	ndm->ndm_pad1    = 0;
2440	ndm->ndm_pad2    = 0;
2441	ndm->ndm_flags	 = neigh->flags;
2442	ndm->ndm_type	 = neigh->type;
2443	ndm->ndm_ifindex = neigh->dev->ifindex;
2444
2445	if (nla_put(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key))
2446		goto nla_put_failure;
2447
2448	read_lock_bh(&neigh->lock);
2449	ndm->ndm_state	 = neigh->nud_state;
2450	if (neigh->nud_state & NUD_VALID) {
2451		char haddr[MAX_ADDR_LEN];
2452
2453		neigh_ha_snapshot(haddr, neigh, neigh->dev);
2454		if (nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, haddr) < 0) {
2455			read_unlock_bh(&neigh->lock);
2456			goto nla_put_failure;
2457		}
2458	}
2459
2460	ci.ndm_used	 = jiffies_to_clock_t(now - neigh->used);
2461	ci.ndm_confirmed = jiffies_to_clock_t(now - neigh->confirmed);
2462	ci.ndm_updated	 = jiffies_to_clock_t(now - neigh->updated);
2463	ci.ndm_refcnt	 = refcount_read(&neigh->refcnt) - 1;
2464	read_unlock_bh(&neigh->lock);
2465
2466	if (nla_put_u32(skb, NDA_PROBES, atomic_read(&neigh->probes)) ||
2467	    nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
2468		goto nla_put_failure;
2469
2470	if (neigh->protocol && nla_put_u8(skb, NDA_PROTOCOL, neigh->protocol))
2471		goto nla_put_failure;
2472
2473	nlmsg_end(skb, nlh);
2474	return 0;
2475
2476nla_put_failure:
2477	nlmsg_cancel(skb, nlh);
2478	return -EMSGSIZE;
2479}
2480
2481static int pneigh_fill_info(struct sk_buff *skb, struct pneigh_entry *pn,
2482			    u32 pid, u32 seq, int type, unsigned int flags,
2483			    struct neigh_table *tbl)
2484{
2485	struct nlmsghdr *nlh;
2486	struct ndmsg *ndm;
2487
2488	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
2489	if (nlh == NULL)
2490		return -EMSGSIZE;
2491
2492	ndm = nlmsg_data(nlh);
2493	ndm->ndm_family	 = tbl->family;
2494	ndm->ndm_pad1    = 0;
2495	ndm->ndm_pad2    = 0;
2496	ndm->ndm_flags	 = pn->flags | NTF_PROXY;
2497	ndm->ndm_type	 = RTN_UNICAST;
2498	ndm->ndm_ifindex = pn->dev ? pn->dev->ifindex : 0;
2499	ndm->ndm_state	 = NUD_NONE;
2500
2501	if (nla_put(skb, NDA_DST, tbl->key_len, pn->key))
2502		goto nla_put_failure;
2503
2504	if (pn->protocol && nla_put_u8(skb, NDA_PROTOCOL, pn->protocol))
2505		goto nla_put_failure;
2506
2507	nlmsg_end(skb, nlh);
2508	return 0;
2509
2510nla_put_failure:
2511	nlmsg_cancel(skb, nlh);
2512	return -EMSGSIZE;
2513}
2514
2515static void neigh_update_notify(struct neighbour *neigh, u32 nlmsg_pid)
2516{
2517	call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
2518	__neigh_notify(neigh, RTM_NEWNEIGH, 0, nlmsg_pid);
2519}
2520
2521static bool neigh_master_filtered(struct net_device *dev, int master_idx)
2522{
2523	struct net_device *master;
2524
2525	if (!master_idx)
2526		return false;
2527
2528	master = dev ? netdev_master_upper_dev_get(dev) : NULL;
2529	if (!master || master->ifindex != master_idx)
2530		return true;
2531
2532	return false;
2533}
2534
2535static bool neigh_ifindex_filtered(struct net_device *dev, int filter_idx)
2536{
2537	if (filter_idx && (!dev || dev->ifindex != filter_idx))
2538		return true;
2539
2540	return false;
2541}
2542
2543struct neigh_dump_filter {
2544	int master_idx;
2545	int dev_idx;
2546};
2547
2548static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2549			    struct netlink_callback *cb,
2550			    struct neigh_dump_filter *filter)
2551{
2552	struct net *net = sock_net(skb->sk);
2553	struct neighbour *n;
2554	int rc, h, s_h = cb->args[1];
2555	int idx, s_idx = idx = cb->args[2];
2556	struct neigh_hash_table *nht;
2557	unsigned int flags = NLM_F_MULTI;
2558
2559	if (filter->dev_idx || filter->master_idx)
2560		flags |= NLM_F_DUMP_FILTERED;
2561
2562	rcu_read_lock_bh();
2563	nht = rcu_dereference_bh(tbl->nht);
2564
2565	for (h = s_h; h < (1 << nht->hash_shift); h++) {
 
 
2566		if (h > s_h)
2567			s_idx = 0;
2568		for (n = rcu_dereference_bh(nht->hash_buckets[h]), idx = 0;
2569		     n != NULL;
2570		     n = rcu_dereference_bh(n->next)) {
2571			if (idx < s_idx || !net_eq(dev_net(n->dev), net))
2572				goto next;
2573			if (neigh_ifindex_filtered(n->dev, filter->dev_idx) ||
2574			    neigh_master_filtered(n->dev, filter->master_idx))
2575				goto next;
2576			if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2577					    cb->nlh->nlmsg_seq,
2578					    RTM_NEWNEIGH,
2579					    flags) < 0) {
2580				rc = -1;
2581				goto out;
2582			}
2583next:
2584			idx++;
2585		}
2586	}
2587	rc = skb->len;
2588out:
2589	rcu_read_unlock_bh();
2590	cb->args[1] = h;
2591	cb->args[2] = idx;
2592	return rc;
2593}
2594
2595static int pneigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
2596			     struct netlink_callback *cb,
2597			     struct neigh_dump_filter *filter)
2598{
2599	struct pneigh_entry *n;
2600	struct net *net = sock_net(skb->sk);
2601	int rc, h, s_h = cb->args[3];
2602	int idx, s_idx = idx = cb->args[4];
2603	unsigned int flags = NLM_F_MULTI;
2604
2605	if (filter->dev_idx || filter->master_idx)
2606		flags |= NLM_F_DUMP_FILTERED;
2607
2608	read_lock_bh(&tbl->lock);
2609
2610	for (h = s_h; h <= PNEIGH_HASHMASK; h++) {
2611		if (h > s_h)
2612			s_idx = 0;
2613		for (n = tbl->phash_buckets[h], idx = 0; n; n = n->next) {
2614			if (idx < s_idx || pneigh_net(n) != net)
2615				goto next;
2616			if (neigh_ifindex_filtered(n->dev, filter->dev_idx) ||
2617			    neigh_master_filtered(n->dev, filter->master_idx))
2618				goto next;
2619			if (pneigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
2620					    cb->nlh->nlmsg_seq,
2621					    RTM_NEWNEIGH, flags, tbl) < 0) {
2622				read_unlock_bh(&tbl->lock);
2623				rc = -1;
2624				goto out;
2625			}
2626		next:
2627			idx++;
2628		}
2629	}
2630
2631	read_unlock_bh(&tbl->lock);
2632	rc = skb->len;
2633out:
2634	cb->args[3] = h;
2635	cb->args[4] = idx;
2636	return rc;
2637
2638}
2639
2640static int neigh_valid_dump_req(const struct nlmsghdr *nlh,
2641				bool strict_check,
2642				struct neigh_dump_filter *filter,
2643				struct netlink_ext_ack *extack)
2644{
2645	struct nlattr *tb[NDA_MAX + 1];
2646	int err, i;
2647
2648	if (strict_check) {
2649		struct ndmsg *ndm;
2650
2651		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) {
2652			NL_SET_ERR_MSG(extack, "Invalid header for neighbor dump request");
2653			return -EINVAL;
2654		}
2655
2656		ndm = nlmsg_data(nlh);
2657		if (ndm->ndm_pad1  || ndm->ndm_pad2  || ndm->ndm_ifindex ||
2658		    ndm->ndm_state || ndm->ndm_type) {
2659			NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor dump request");
2660			return -EINVAL;
2661		}
2662
2663		if (ndm->ndm_flags & ~NTF_PROXY) {
2664			NL_SET_ERR_MSG(extack, "Invalid flags in header for neighbor dump request");
2665			return -EINVAL;
2666		}
2667
2668		err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct ndmsg),
2669						    tb, NDA_MAX, nda_policy,
2670						    extack);
2671	} else {
2672		err = nlmsg_parse_deprecated(nlh, sizeof(struct ndmsg), tb,
2673					     NDA_MAX, nda_policy, extack);
2674	}
2675	if (err < 0)
2676		return err;
2677
2678	for (i = 0; i <= NDA_MAX; ++i) {
2679		if (!tb[i])
2680			continue;
2681
2682		/* all new attributes should require strict_check */
2683		switch (i) {
2684		case NDA_IFINDEX:
2685			filter->dev_idx = nla_get_u32(tb[i]);
2686			break;
2687		case NDA_MASTER:
2688			filter->master_idx = nla_get_u32(tb[i]);
2689			break;
2690		default:
2691			if (strict_check) {
2692				NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor dump request");
2693				return -EINVAL;
2694			}
2695		}
2696	}
2697
2698	return 0;
2699}
2700
2701static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
2702{
2703	const struct nlmsghdr *nlh = cb->nlh;
2704	struct neigh_dump_filter filter = {};
2705	struct neigh_table *tbl;
2706	int t, family, s_t;
2707	int proxy = 0;
2708	int err;
2709
2710	family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family;
2711
2712	/* check for full ndmsg structure presence, family member is
2713	 * the same for both structures
2714	 */
2715	if (nlmsg_len(nlh) >= sizeof(struct ndmsg) &&
2716	    ((struct ndmsg *)nlmsg_data(nlh))->ndm_flags == NTF_PROXY)
2717		proxy = 1;
2718
2719	err = neigh_valid_dump_req(nlh, cb->strict_check, &filter, cb->extack);
2720	if (err < 0 && cb->strict_check)
2721		return err;
2722
 
 
2723	s_t = cb->args[0];
2724
2725	for (t = 0; t < NEIGH_NR_TABLES; t++) {
2726		tbl = neigh_tables[t];
2727
2728		if (!tbl)
2729			continue;
2730		if (t < s_t || (family && tbl->family != family))
2731			continue;
2732		if (t > s_t)
2733			memset(&cb->args[1], 0, sizeof(cb->args) -
2734						sizeof(cb->args[0]));
2735		if (proxy)
2736			err = pneigh_dump_table(tbl, skb, cb, &filter);
2737		else
2738			err = neigh_dump_table(tbl, skb, cb, &filter);
2739		if (err < 0)
2740			break;
2741	}
 
2742
2743	cb->args[0] = t;
2744	return skb->len;
2745}
2746
2747static int neigh_valid_get_req(const struct nlmsghdr *nlh,
2748			       struct neigh_table **tbl,
2749			       void **dst, int *dev_idx, u8 *ndm_flags,
2750			       struct netlink_ext_ack *extack)
2751{
2752	struct nlattr *tb[NDA_MAX + 1];
2753	struct ndmsg *ndm;
2754	int err, i;
2755
2756	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) {
2757		NL_SET_ERR_MSG(extack, "Invalid header for neighbor get request");
2758		return -EINVAL;
2759	}
2760
2761	ndm = nlmsg_data(nlh);
2762	if (ndm->ndm_pad1  || ndm->ndm_pad2  || ndm->ndm_state ||
2763	    ndm->ndm_type) {
2764		NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor get request");
2765		return -EINVAL;
2766	}
2767
2768	if (ndm->ndm_flags & ~NTF_PROXY) {
2769		NL_SET_ERR_MSG(extack, "Invalid flags in header for neighbor get request");
2770		return -EINVAL;
2771	}
2772
2773	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct ndmsg), tb,
2774					    NDA_MAX, nda_policy, extack);
2775	if (err < 0)
2776		return err;
2777
2778	*ndm_flags = ndm->ndm_flags;
2779	*dev_idx = ndm->ndm_ifindex;
2780	*tbl = neigh_find_table(ndm->ndm_family);
2781	if (*tbl == NULL) {
2782		NL_SET_ERR_MSG(extack, "Unsupported family in header for neighbor get request");
2783		return -EAFNOSUPPORT;
2784	}
2785
2786	for (i = 0; i <= NDA_MAX; ++i) {
2787		if (!tb[i])
2788			continue;
2789
2790		switch (i) {
2791		case NDA_DST:
2792			if (nla_len(tb[i]) != (int)(*tbl)->key_len) {
2793				NL_SET_ERR_MSG(extack, "Invalid network address in neighbor get request");
2794				return -EINVAL;
2795			}
2796			*dst = nla_data(tb[i]);
2797			break;
2798		default:
2799			NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor get request");
2800			return -EINVAL;
2801		}
2802	}
2803
2804	return 0;
2805}
2806
2807static inline size_t neigh_nlmsg_size(void)
2808{
2809	return NLMSG_ALIGN(sizeof(struct ndmsg))
2810	       + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2811	       + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */
2812	       + nla_total_size(sizeof(struct nda_cacheinfo))
2813	       + nla_total_size(4)  /* NDA_PROBES */
2814	       + nla_total_size(1); /* NDA_PROTOCOL */
2815}
2816
2817static int neigh_get_reply(struct net *net, struct neighbour *neigh,
2818			   u32 pid, u32 seq)
2819{
2820	struct sk_buff *skb;
2821	int err = 0;
2822
2823	skb = nlmsg_new(neigh_nlmsg_size(), GFP_KERNEL);
2824	if (!skb)
2825		return -ENOBUFS;
2826
2827	err = neigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0);
2828	if (err) {
2829		kfree_skb(skb);
2830		goto errout;
2831	}
2832
2833	err = rtnl_unicast(skb, net, pid);
2834errout:
2835	return err;
2836}
2837
2838static inline size_t pneigh_nlmsg_size(void)
2839{
2840	return NLMSG_ALIGN(sizeof(struct ndmsg))
2841	       + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
2842	       + nla_total_size(1); /* NDA_PROTOCOL */
2843}
2844
2845static int pneigh_get_reply(struct net *net, struct pneigh_entry *neigh,
2846			    u32 pid, u32 seq, struct neigh_table *tbl)
2847{
2848	struct sk_buff *skb;
2849	int err = 0;
2850
2851	skb = nlmsg_new(pneigh_nlmsg_size(), GFP_KERNEL);
2852	if (!skb)
2853		return -ENOBUFS;
2854
2855	err = pneigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0, tbl);
2856	if (err) {
2857		kfree_skb(skb);
2858		goto errout;
2859	}
2860
2861	err = rtnl_unicast(skb, net, pid);
2862errout:
2863	return err;
2864}
2865
2866static int neigh_get(struct sk_buff *in_skb, struct nlmsghdr *nlh,
2867		     struct netlink_ext_ack *extack)
2868{
2869	struct net *net = sock_net(in_skb->sk);
2870	struct net_device *dev = NULL;
2871	struct neigh_table *tbl = NULL;
2872	struct neighbour *neigh;
2873	void *dst = NULL;
2874	u8 ndm_flags = 0;
2875	int dev_idx = 0;
2876	int err;
2877
2878	err = neigh_valid_get_req(nlh, &tbl, &dst, &dev_idx, &ndm_flags,
2879				  extack);
2880	if (err < 0)
2881		return err;
2882
2883	if (dev_idx) {
2884		dev = __dev_get_by_index(net, dev_idx);
2885		if (!dev) {
2886			NL_SET_ERR_MSG(extack, "Unknown device ifindex");
2887			return -ENODEV;
2888		}
2889	}
2890
2891	if (!dst) {
2892		NL_SET_ERR_MSG(extack, "Network address not specified");
2893		return -EINVAL;
2894	}
2895
2896	if (ndm_flags & NTF_PROXY) {
2897		struct pneigh_entry *pn;
2898
2899		pn = pneigh_lookup(tbl, net, dst, dev, 0);
2900		if (!pn) {
2901			NL_SET_ERR_MSG(extack, "Proxy neighbour entry not found");
2902			return -ENOENT;
2903		}
2904		return pneigh_get_reply(net, pn, NETLINK_CB(in_skb).portid,
2905					nlh->nlmsg_seq, tbl);
2906	}
2907
2908	if (!dev) {
2909		NL_SET_ERR_MSG(extack, "No device specified");
2910		return -EINVAL;
2911	}
2912
2913	neigh = neigh_lookup(tbl, dst, dev);
2914	if (!neigh) {
2915		NL_SET_ERR_MSG(extack, "Neighbour entry not found");
2916		return -ENOENT;
2917	}
2918
2919	err = neigh_get_reply(net, neigh, NETLINK_CB(in_skb).portid,
2920			      nlh->nlmsg_seq);
2921
2922	neigh_release(neigh);
2923
2924	return err;
2925}
2926
2927void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
2928{
2929	int chain;
2930	struct neigh_hash_table *nht;
2931
2932	rcu_read_lock_bh();
2933	nht = rcu_dereference_bh(tbl->nht);
2934
2935	read_lock(&tbl->lock); /* avoid resizes */
2936	for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2937		struct neighbour *n;
2938
2939		for (n = rcu_dereference_bh(nht->hash_buckets[chain]);
2940		     n != NULL;
2941		     n = rcu_dereference_bh(n->next))
2942			cb(n, cookie);
2943	}
2944	read_unlock(&tbl->lock);
2945	rcu_read_unlock_bh();
2946}
2947EXPORT_SYMBOL(neigh_for_each);
2948
2949/* The tbl->lock must be held as a writer and BH disabled. */
2950void __neigh_for_each_release(struct neigh_table *tbl,
2951			      int (*cb)(struct neighbour *))
2952{
2953	int chain;
2954	struct neigh_hash_table *nht;
2955
2956	nht = rcu_dereference_protected(tbl->nht,
2957					lockdep_is_held(&tbl->lock));
2958	for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
2959		struct neighbour *n;
2960		struct neighbour __rcu **np;
2961
2962		np = &nht->hash_buckets[chain];
2963		while ((n = rcu_dereference_protected(*np,
2964					lockdep_is_held(&tbl->lock))) != NULL) {
2965			int release;
2966
2967			write_lock(&n->lock);
2968			release = cb(n);
2969			if (release) {
2970				rcu_assign_pointer(*np,
2971					rcu_dereference_protected(n->next,
2972						lockdep_is_held(&tbl->lock)));
2973				neigh_mark_dead(n);
2974			} else
2975				np = &n->next;
2976			write_unlock(&n->lock);
2977			if (release)
2978				neigh_cleanup_and_release(n);
2979		}
2980	}
2981}
2982EXPORT_SYMBOL(__neigh_for_each_release);
2983
2984int neigh_xmit(int index, struct net_device *dev,
2985	       const void *addr, struct sk_buff *skb)
2986{
2987	int err = -EAFNOSUPPORT;
2988	if (likely(index < NEIGH_NR_TABLES)) {
2989		struct neigh_table *tbl;
2990		struct neighbour *neigh;
2991
2992		tbl = neigh_tables[index];
2993		if (!tbl)
2994			goto out;
2995		rcu_read_lock_bh();
2996		if (index == NEIGH_ARP_TABLE) {
2997			u32 key = *((u32 *)addr);
2998
2999			neigh = __ipv4_neigh_lookup_noref(dev, key);
3000		} else {
3001			neigh = __neigh_lookup_noref(tbl, addr, dev);
3002		}
3003		if (!neigh)
3004			neigh = __neigh_create(tbl, addr, dev, false);
3005		err = PTR_ERR(neigh);
3006		if (IS_ERR(neigh)) {
3007			rcu_read_unlock_bh();
3008			goto out_kfree_skb;
3009		}
3010		err = neigh->output(neigh, skb);
3011		rcu_read_unlock_bh();
3012	}
3013	else if (index == NEIGH_LINK_TABLE) {
3014		err = dev_hard_header(skb, dev, ntohs(skb->protocol),
3015				      addr, NULL, skb->len);
3016		if (err < 0)
3017			goto out_kfree_skb;
3018		err = dev_queue_xmit(skb);
3019	}
3020out:
3021	return err;
3022out_kfree_skb:
3023	kfree_skb(skb);
3024	goto out;
3025}
3026EXPORT_SYMBOL(neigh_xmit);
3027
3028#ifdef CONFIG_PROC_FS
3029
3030static struct neighbour *neigh_get_first(struct seq_file *seq)
3031{
3032	struct neigh_seq_state *state = seq->private;
3033	struct net *net = seq_file_net(seq);
3034	struct neigh_hash_table *nht = state->nht;
3035	struct neighbour *n = NULL;
3036	int bucket;
3037
3038	state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
3039	for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) {
3040		n = rcu_dereference_bh(nht->hash_buckets[bucket]);
3041
3042		while (n) {
3043			if (!net_eq(dev_net(n->dev), net))
3044				goto next;
3045			if (state->neigh_sub_iter) {
3046				loff_t fakep = 0;
3047				void *v;
3048
3049				v = state->neigh_sub_iter(state, n, &fakep);
3050				if (!v)
3051					goto next;
3052			}
3053			if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
3054				break;
3055			if (n->nud_state & ~NUD_NOARP)
3056				break;
3057next:
3058			n = rcu_dereference_bh(n->next);
3059		}
3060
3061		if (n)
3062			break;
3063	}
3064	state->bucket = bucket;
3065
3066	return n;
3067}
3068
3069static struct neighbour *neigh_get_next(struct seq_file *seq,
3070					struct neighbour *n,
3071					loff_t *pos)
3072{
3073	struct neigh_seq_state *state = seq->private;
3074	struct net *net = seq_file_net(seq);
3075	struct neigh_hash_table *nht = state->nht;
3076
3077	if (state->neigh_sub_iter) {
3078		void *v = state->neigh_sub_iter(state, n, pos);
3079		if (v)
3080			return n;
3081	}
3082	n = rcu_dereference_bh(n->next);
3083
3084	while (1) {
3085		while (n) {
3086			if (!net_eq(dev_net(n->dev), net))
3087				goto next;
3088			if (state->neigh_sub_iter) {
3089				void *v = state->neigh_sub_iter(state, n, pos);
3090				if (v)
3091					return n;
3092				goto next;
3093			}
3094			if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
3095				break;
3096
3097			if (n->nud_state & ~NUD_NOARP)
3098				break;
3099next:
3100			n = rcu_dereference_bh(n->next);
3101		}
3102
3103		if (n)
3104			break;
3105
3106		if (++state->bucket >= (1 << nht->hash_shift))
3107			break;
3108
3109		n = rcu_dereference_bh(nht->hash_buckets[state->bucket]);
3110	}
3111
3112	if (n && pos)
3113		--(*pos);
3114	return n;
3115}
3116
3117static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
3118{
3119	struct neighbour *n = neigh_get_first(seq);
3120
3121	if (n) {
3122		--(*pos);
3123		while (*pos) {
3124			n = neigh_get_next(seq, n, pos);
3125			if (!n)
3126				break;
3127		}
3128	}
3129	return *pos ? NULL : n;
3130}
3131
3132static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
3133{
3134	struct neigh_seq_state *state = seq->private;
3135	struct net *net = seq_file_net(seq);
3136	struct neigh_table *tbl = state->tbl;
3137	struct pneigh_entry *pn = NULL;
3138	int bucket = state->bucket;
3139
3140	state->flags |= NEIGH_SEQ_IS_PNEIGH;
3141	for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
3142		pn = tbl->phash_buckets[bucket];
3143		while (pn && !net_eq(pneigh_net(pn), net))
3144			pn = pn->next;
3145		if (pn)
3146			break;
3147	}
3148	state->bucket = bucket;
3149
3150	return pn;
3151}
3152
3153static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
3154					    struct pneigh_entry *pn,
3155					    loff_t *pos)
3156{
3157	struct neigh_seq_state *state = seq->private;
3158	struct net *net = seq_file_net(seq);
3159	struct neigh_table *tbl = state->tbl;
3160
3161	do {
3162		pn = pn->next;
3163	} while (pn && !net_eq(pneigh_net(pn), net));
3164
3165	while (!pn) {
3166		if (++state->bucket > PNEIGH_HASHMASK)
3167			break;
3168		pn = tbl->phash_buckets[state->bucket];
3169		while (pn && !net_eq(pneigh_net(pn), net))
3170			pn = pn->next;
3171		if (pn)
3172			break;
3173	}
3174
3175	if (pn && pos)
3176		--(*pos);
3177
3178	return pn;
3179}
3180
3181static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
3182{
3183	struct pneigh_entry *pn = pneigh_get_first(seq);
3184
3185	if (pn) {
3186		--(*pos);
3187		while (*pos) {
3188			pn = pneigh_get_next(seq, pn, pos);
3189			if (!pn)
3190				break;
3191		}
3192	}
3193	return *pos ? NULL : pn;
3194}
3195
3196static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
3197{
3198	struct neigh_seq_state *state = seq->private;
3199	void *rc;
3200	loff_t idxpos = *pos;
3201
3202	rc = neigh_get_idx(seq, &idxpos);
3203	if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
3204		rc = pneigh_get_idx(seq, &idxpos);
3205
3206	return rc;
3207}
3208
3209void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
3210	__acquires(tbl->lock)
3211	__acquires(rcu_bh)
3212{
3213	struct neigh_seq_state *state = seq->private;
3214
3215	state->tbl = tbl;
3216	state->bucket = 0;
3217	state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
3218
3219	rcu_read_lock_bh();
3220	state->nht = rcu_dereference_bh(tbl->nht);
3221	read_lock(&tbl->lock);
3222
3223	return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
3224}
3225EXPORT_SYMBOL(neigh_seq_start);
3226
3227void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3228{
3229	struct neigh_seq_state *state;
3230	void *rc;
3231
3232	if (v == SEQ_START_TOKEN) {
3233		rc = neigh_get_first(seq);
3234		goto out;
3235	}
3236
3237	state = seq->private;
3238	if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
3239		rc = neigh_get_next(seq, v, NULL);
3240		if (rc)
3241			goto out;
3242		if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
3243			rc = pneigh_get_first(seq);
3244	} else {
3245		BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
3246		rc = pneigh_get_next(seq, v, NULL);
3247	}
3248out:
3249	++(*pos);
3250	return rc;
3251}
3252EXPORT_SYMBOL(neigh_seq_next);
3253
3254void neigh_seq_stop(struct seq_file *seq, void *v)
3255	__releases(tbl->lock)
3256	__releases(rcu_bh)
3257{
3258	struct neigh_seq_state *state = seq->private;
3259	struct neigh_table *tbl = state->tbl;
3260
3261	read_unlock(&tbl->lock);
3262	rcu_read_unlock_bh();
3263}
3264EXPORT_SYMBOL(neigh_seq_stop);
3265
3266/* statistics via seq_file */
3267
3268static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
3269{
3270	struct neigh_table *tbl = PDE_DATA(file_inode(seq->file));
3271	int cpu;
3272
3273	if (*pos == 0)
3274		return SEQ_START_TOKEN;
3275
3276	for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
3277		if (!cpu_possible(cpu))
3278			continue;
3279		*pos = cpu+1;
3280		return per_cpu_ptr(tbl->stats, cpu);
3281	}
3282	return NULL;
3283}
3284
3285static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3286{
3287	struct neigh_table *tbl = PDE_DATA(file_inode(seq->file));
3288	int cpu;
3289
3290	for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
3291		if (!cpu_possible(cpu))
3292			continue;
3293		*pos = cpu+1;
3294		return per_cpu_ptr(tbl->stats, cpu);
3295	}
3296	return NULL;
3297}
3298
3299static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
3300{
3301
3302}
3303
3304static int neigh_stat_seq_show(struct seq_file *seq, void *v)
3305{
3306	struct neigh_table *tbl = PDE_DATA(file_inode(seq->file));
3307	struct neigh_statistics *st = v;
3308
3309	if (v == SEQ_START_TOKEN) {
3310		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");
3311		return 0;
3312	}
3313
3314	seq_printf(seq, "%08x  %08lx %08lx %08lx  %08lx %08lx  %08lx  "
3315			"%08lx %08lx  %08lx %08lx %08lx %08lx\n",
3316		   atomic_read(&tbl->entries),
3317
3318		   st->allocs,
3319		   st->destroys,
3320		   st->hash_grows,
3321
3322		   st->lookups,
3323		   st->hits,
3324
3325		   st->res_failed,
3326
3327		   st->rcv_probes_mcast,
3328		   st->rcv_probes_ucast,
3329
3330		   st->periodic_gc_runs,
3331		   st->forced_gc_runs,
3332		   st->unres_discards,
3333		   st->table_fulls
3334		   );
3335
3336	return 0;
3337}
3338
3339static const struct seq_operations neigh_stat_seq_ops = {
3340	.start	= neigh_stat_seq_start,
3341	.next	= neigh_stat_seq_next,
3342	.stop	= neigh_stat_seq_stop,
3343	.show	= neigh_stat_seq_show,
3344};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3345#endif /* CONFIG_PROC_FS */
3346
3347static void __neigh_notify(struct neighbour *n, int type, int flags,
3348			   u32 pid)
 
 
 
 
 
 
 
 
3349{
3350	struct net *net = dev_net(n->dev);
3351	struct sk_buff *skb;
3352	int err = -ENOBUFS;
3353
3354	skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
3355	if (skb == NULL)
3356		goto errout;
3357
3358	err = neigh_fill_info(skb, n, pid, 0, type, flags);
3359	if (err < 0) {
3360		/* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
3361		WARN_ON(err == -EMSGSIZE);
3362		kfree_skb(skb);
3363		goto errout;
3364	}
3365	rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
3366	return;
3367errout:
3368	if (err < 0)
3369		rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
3370}
3371
 
3372void neigh_app_ns(struct neighbour *n)
3373{
3374	__neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST, 0);
3375}
3376EXPORT_SYMBOL(neigh_app_ns);
 
3377
3378#ifdef CONFIG_SYSCTL
3379static int unres_qlen_max = INT_MAX / SKB_TRUESIZE(ETH_FRAME_LEN);
3380
3381static int proc_unres_qlen(struct ctl_table *ctl, int write,
3382			   void __user *buffer, size_t *lenp, loff_t *ppos)
3383{
3384	int size, ret;
3385	struct ctl_table tmp = *ctl;
3386
3387	tmp.extra1 = SYSCTL_ZERO;
3388	tmp.extra2 = &unres_qlen_max;
3389	tmp.data = &size;
3390
3391	size = *(int *)ctl->data / SKB_TRUESIZE(ETH_FRAME_LEN);
3392	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
3393
3394	if (write && !ret)
3395		*(int *)ctl->data = size * SKB_TRUESIZE(ETH_FRAME_LEN);
3396	return ret;
3397}
3398
3399static struct neigh_parms *neigh_get_dev_parms_rcu(struct net_device *dev,
3400						   int family)
3401{
3402	switch (family) {
3403	case AF_INET:
3404		return __in_dev_arp_parms_get_rcu(dev);
3405	case AF_INET6:
3406		return __in6_dev_nd_parms_get_rcu(dev);
3407	}
3408	return NULL;
3409}
3410
3411static void neigh_copy_dflt_parms(struct net *net, struct neigh_parms *p,
3412				  int index)
3413{
3414	struct net_device *dev;
3415	int family = neigh_parms_family(p);
3416
3417	rcu_read_lock();
3418	for_each_netdev_rcu(net, dev) {
3419		struct neigh_parms *dst_p =
3420				neigh_get_dev_parms_rcu(dev, family);
3421
3422		if (dst_p && !test_bit(index, dst_p->data_state))
3423			dst_p->data[index] = p->data[index];
3424	}
3425	rcu_read_unlock();
3426}
3427
3428static void neigh_proc_update(struct ctl_table *ctl, int write)
3429{
3430	struct net_device *dev = ctl->extra1;
3431	struct neigh_parms *p = ctl->extra2;
3432	struct net *net = neigh_parms_net(p);
3433	int index = (int *) ctl->data - p->data;
3434
3435	if (!write)
3436		return;
3437
3438	set_bit(index, p->data_state);
3439	if (index == NEIGH_VAR_DELAY_PROBE_TIME)
3440		call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
3441	if (!dev) /* NULL dev means this is default value */
3442		neigh_copy_dflt_parms(net, p, index);
3443}
3444
3445static int neigh_proc_dointvec_zero_intmax(struct ctl_table *ctl, int write,
3446					   void __user *buffer,
3447					   size_t *lenp, loff_t *ppos)
3448{
3449	struct ctl_table tmp = *ctl;
3450	int ret;
3451
3452	tmp.extra1 = SYSCTL_ZERO;
3453	tmp.extra2 = SYSCTL_INT_MAX;
3454
3455	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
3456	neigh_proc_update(ctl, write);
3457	return ret;
3458}
3459
3460int neigh_proc_dointvec(struct ctl_table *ctl, int write,
3461			void __user *buffer, size_t *lenp, loff_t *ppos)
3462{
3463	int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
3464
3465	neigh_proc_update(ctl, write);
3466	return ret;
3467}
3468EXPORT_SYMBOL(neigh_proc_dointvec);
3469
3470int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write,
3471				void __user *buffer,
3472				size_t *lenp, loff_t *ppos)
3473{
3474	int ret = proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
3475
3476	neigh_proc_update(ctl, write);
3477	return ret;
3478}
3479EXPORT_SYMBOL(neigh_proc_dointvec_jiffies);
3480
3481static int neigh_proc_dointvec_userhz_jiffies(struct ctl_table *ctl, int write,
3482					      void __user *buffer,
3483					      size_t *lenp, loff_t *ppos)
3484{
3485	int ret = proc_dointvec_userhz_jiffies(ctl, write, buffer, lenp, ppos);
3486
3487	neigh_proc_update(ctl, write);
3488	return ret;
3489}
3490
3491int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
3492				   void __user *buffer,
3493				   size_t *lenp, loff_t *ppos)
3494{
3495	int ret = proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
3496
3497	neigh_proc_update(ctl, write);
3498	return ret;
3499}
3500EXPORT_SYMBOL(neigh_proc_dointvec_ms_jiffies);
3501
3502static int neigh_proc_dointvec_unres_qlen(struct ctl_table *ctl, int write,
3503					  void __user *buffer,
3504					  size_t *lenp, loff_t *ppos)
3505{
3506	int ret = proc_unres_qlen(ctl, write, buffer, lenp, ppos);
3507
3508	neigh_proc_update(ctl, write);
3509	return ret;
3510}
3511
3512static int neigh_proc_base_reachable_time(struct ctl_table *ctl, int write,
3513					  void __user *buffer,
3514					  size_t *lenp, loff_t *ppos)
3515{
3516	struct neigh_parms *p = ctl->extra2;
3517	int ret;
3518
3519	if (strcmp(ctl->procname, "base_reachable_time") == 0)
3520		ret = neigh_proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
3521	else if (strcmp(ctl->procname, "base_reachable_time_ms") == 0)
3522		ret = neigh_proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
3523	else
3524		ret = -1;
3525
3526	if (write && ret == 0) {
3527		/* update reachable_time as well, otherwise, the change will
3528		 * only be effective after the next time neigh_periodic_work
3529		 * decides to recompute it
3530		 */
3531		p->reachable_time =
3532			neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
3533	}
3534	return ret;
3535}
3536
3537#define NEIGH_PARMS_DATA_OFFSET(index)	\
3538	(&((struct neigh_parms *) 0)->data[index])
3539
3540#define NEIGH_SYSCTL_ENTRY(attr, data_attr, name, mval, proc) \
3541	[NEIGH_VAR_ ## attr] = { \
3542		.procname	= name, \
3543		.data		= NEIGH_PARMS_DATA_OFFSET(NEIGH_VAR_ ## data_attr), \
3544		.maxlen		= sizeof(int), \
3545		.mode		= mval, \
3546		.proc_handler	= proc, \
3547	}
3548
3549#define NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(attr, name) \
3550	NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_zero_intmax)
3551
3552#define NEIGH_SYSCTL_JIFFIES_ENTRY(attr, name) \
3553	NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_jiffies)
3554
3555#define NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(attr, name) \
3556	NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_userhz_jiffies)
3557
3558#define NEIGH_SYSCTL_MS_JIFFIES_ENTRY(attr, name) \
3559	NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_ms_jiffies)
3560
3561#define NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(attr, data_attr, name) \
3562	NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_ms_jiffies)
3563
3564#define NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(attr, data_attr, name) \
3565	NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_unres_qlen)
3566
3567static struct neigh_sysctl_table {
3568	struct ctl_table_header *sysctl_header;
3569	struct ctl_table neigh_vars[NEIGH_VAR_MAX + 1];
 
3570} neigh_sysctl_template __read_mostly = {
3571	.neigh_vars = {
3572		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_PROBES, "mcast_solicit"),
3573		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(UCAST_PROBES, "ucast_solicit"),
3574		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(APP_PROBES, "app_solicit"),
3575		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_REPROBES, "mcast_resolicit"),
3576		NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(RETRANS_TIME, "retrans_time"),
3577		NEIGH_SYSCTL_JIFFIES_ENTRY(BASE_REACHABLE_TIME, "base_reachable_time"),
3578		NEIGH_SYSCTL_JIFFIES_ENTRY(DELAY_PROBE_TIME, "delay_first_probe_time"),
3579		NEIGH_SYSCTL_JIFFIES_ENTRY(GC_STALETIME, "gc_stale_time"),
3580		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(QUEUE_LEN_BYTES, "unres_qlen_bytes"),
3581		NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(PROXY_QLEN, "proxy_qlen"),
3582		NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(ANYCAST_DELAY, "anycast_delay"),
3583		NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(PROXY_DELAY, "proxy_delay"),
3584		NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(LOCKTIME, "locktime"),
3585		NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(QUEUE_LEN, QUEUE_LEN_BYTES, "unres_qlen"),
3586		NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(RETRANS_TIME_MS, RETRANS_TIME, "retrans_time_ms"),
3587		NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(BASE_REACHABLE_TIME_MS, BASE_REACHABLE_TIME, "base_reachable_time_ms"),
3588		[NEIGH_VAR_GC_INTERVAL] = {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3589			.procname	= "gc_interval",
3590			.maxlen		= sizeof(int),
3591			.mode		= 0644,
3592			.proc_handler	= proc_dointvec_jiffies,
3593		},
3594		[NEIGH_VAR_GC_THRESH1] = {
3595			.procname	= "gc_thresh1",
3596			.maxlen		= sizeof(int),
3597			.mode		= 0644,
3598			.extra1		= SYSCTL_ZERO,
3599			.extra2		= SYSCTL_INT_MAX,
3600			.proc_handler	= proc_dointvec_minmax,
3601		},
3602		[NEIGH_VAR_GC_THRESH2] = {
3603			.procname	= "gc_thresh2",
3604			.maxlen		= sizeof(int),
3605			.mode		= 0644,
3606			.extra1		= SYSCTL_ZERO,
3607			.extra2		= SYSCTL_INT_MAX,
3608			.proc_handler	= proc_dointvec_minmax,
3609		},
3610		[NEIGH_VAR_GC_THRESH3] = {
3611			.procname	= "gc_thresh3",
3612			.maxlen		= sizeof(int),
3613			.mode		= 0644,
3614			.extra1		= SYSCTL_ZERO,
3615			.extra2		= SYSCTL_INT_MAX,
3616			.proc_handler	= proc_dointvec_minmax,
3617		},
3618		{},
3619	},
3620};
3621
3622int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
3623			  proc_handler *handler)
3624{
3625	int i;
3626	struct neigh_sysctl_table *t;
3627	const char *dev_name_source;
3628	char neigh_path[ sizeof("net//neigh/") + IFNAMSIZ + IFNAMSIZ ];
3629	char *p_name;
 
 
 
 
 
 
 
 
 
 
 
3630
3631	t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL);
3632	if (!t)
3633		goto err;
3634
3635	for (i = 0; i < NEIGH_VAR_GC_INTERVAL; i++) {
3636		t->neigh_vars[i].data += (long) p;
3637		t->neigh_vars[i].extra1 = dev;
3638		t->neigh_vars[i].extra2 = p;
3639	}
 
 
 
 
 
 
 
 
 
3640
3641	if (dev) {
3642		dev_name_source = dev->name;
3643		/* Terminate the table early */
3644		memset(&t->neigh_vars[NEIGH_VAR_GC_INTERVAL], 0,
3645		       sizeof(t->neigh_vars[NEIGH_VAR_GC_INTERVAL]));
3646	} else {
3647		struct neigh_table *tbl = p->tbl;
3648		dev_name_source = "default";
3649		t->neigh_vars[NEIGH_VAR_GC_INTERVAL].data = &tbl->gc_interval;
3650		t->neigh_vars[NEIGH_VAR_GC_THRESH1].data = &tbl->gc_thresh1;
3651		t->neigh_vars[NEIGH_VAR_GC_THRESH2].data = &tbl->gc_thresh2;
3652		t->neigh_vars[NEIGH_VAR_GC_THRESH3].data = &tbl->gc_thresh3;
3653	}
3654
 
3655	if (handler) {
3656		/* RetransTime */
3657		t->neigh_vars[NEIGH_VAR_RETRANS_TIME].proc_handler = handler;
 
3658		/* ReachableTime */
3659		t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler = handler;
 
3660		/* RetransTime (in milliseconds)*/
3661		t->neigh_vars[NEIGH_VAR_RETRANS_TIME_MS].proc_handler = handler;
3662		/* ReachableTime (in milliseconds) */
3663		t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler = handler;
3664	} else {
3665		/* Those handlers will update p->reachable_time after
3666		 * base_reachable_time(_ms) is set to ensure the new timer starts being
3667		 * applied after the next neighbour update instead of waiting for
3668		 * neigh_periodic_work to update its value (can be multiple minutes)
3669		 * So any handler that replaces them should do this as well
3670		 */
3671		/* ReachableTime */
3672		t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler =
3673			neigh_proc_base_reachable_time;
3674		/* ReachableTime (in milliseconds) */
3675		t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler =
3676			neigh_proc_base_reachable_time;
3677	}
3678
3679	/* Don't export sysctls to unprivileged users */
3680	if (neigh_parms_net(p)->user_ns != &init_user_ns)
3681		t->neigh_vars[0].procname = NULL;
3682
3683	switch (neigh_parms_family(p)) {
3684	case AF_INET:
3685	      p_name = "ipv4";
3686	      break;
3687	case AF_INET6:
3688	      p_name = "ipv6";
3689	      break;
3690	default:
3691	      BUG();
3692	}
3693
3694	snprintf(neigh_path, sizeof(neigh_path), "net/%s/neigh/%s",
3695		p_name, dev_name_source);
3696	t->sysctl_header =
3697		register_net_sysctl(neigh_parms_net(p), neigh_path, t->neigh_vars);
3698	if (!t->sysctl_header)
3699		goto free;
3700
3701	p->sysctl_table = t;
3702	return 0;
3703
 
 
3704free:
3705	kfree(t);
3706err:
3707	return -ENOBUFS;
3708}
3709EXPORT_SYMBOL(neigh_sysctl_register);
3710
3711void neigh_sysctl_unregister(struct neigh_parms *p)
3712{
3713	if (p->sysctl_table) {
3714		struct neigh_sysctl_table *t = p->sysctl_table;
3715		p->sysctl_table = NULL;
3716		unregister_net_sysctl_table(t->sysctl_header);
 
3717		kfree(t);
3718	}
3719}
3720EXPORT_SYMBOL(neigh_sysctl_unregister);
3721
3722#endif	/* CONFIG_SYSCTL */
3723
3724static int __init neigh_init(void)
3725{
3726	rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL, 0);
3727	rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL, 0);
3728	rtnl_register(PF_UNSPEC, RTM_GETNEIGH, neigh_get, neigh_dump_info, 0);
3729
3730	rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info,
3731		      0);
3732	rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL, 0);
3733
3734	return 0;
3735}
3736
3737subsys_initcall(neigh_init);