neighbour.c 65.3 KB
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/*
 *	Generic address resolution entity
 *
 *	Authors:
 *	Pedro Roque		<roque@di.fc.ul.pt>
 *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
 *
 *	This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 *
 *	Fixes:
 *	Vitaly E. Lavrov	releasing NULL neighbor in neigh_add.
 *	Harald Welte		Add neighbour cache statistics like rtstat
 */

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#include <linux/slab.h>
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#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/socket.h>
#include <linux/netdevice.h>
#include <linux/proc_fs.h>
#ifdef CONFIG_SYSCTL
#include <linux/sysctl.h>
#endif
#include <linux/times.h>
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#include <net/net_namespace.h>
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#include <net/neighbour.h>
#include <net/dst.h>
#include <net/sock.h>
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#include <net/netevent.h>
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#include <net/netlink.h>
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#include <linux/rtnetlink.h>
#include <linux/random.h>
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#include <linux/string.h>
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#include <linux/log2.h>
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#define NEIGH_DEBUG 1

#define NEIGH_PRINTK(x...) printk(x)
#define NEIGH_NOPRINTK(x...) do { ; } while(0)
#define NEIGH_PRINTK0 NEIGH_PRINTK
#define NEIGH_PRINTK1 NEIGH_NOPRINTK
#define NEIGH_PRINTK2 NEIGH_NOPRINTK

#if NEIGH_DEBUG >= 1
#undef NEIGH_PRINTK1
#define NEIGH_PRINTK1 NEIGH_PRINTK
#endif
#if NEIGH_DEBUG >= 2
#undef NEIGH_PRINTK2
#define NEIGH_PRINTK2 NEIGH_PRINTK
#endif

#define PNEIGH_HASHMASK		0xF

static void neigh_timer_handler(unsigned long arg);
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static void __neigh_notify(struct neighbour *n, int type, int flags);
static void neigh_update_notify(struct neighbour *neigh);
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static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev);

static struct neigh_table *neigh_tables;
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#ifdef CONFIG_PROC_FS
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static const struct file_operations neigh_stat_seq_fops;
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#endif
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/*
   Neighbour hash table buckets are protected with rwlock tbl->lock.

   - All the scans/updates to hash buckets MUST be made under this lock.
   - NOTHING clever should be made under this lock: no callbacks
     to protocol backends, no attempts to send something to network.
     It will result in deadlocks, if backend/driver wants to use neighbour
     cache.
   - If the entry requires some non-trivial actions, increase
     its reference count and release table lock.

   Neighbour entries are protected:
   - with reference count.
   - with rwlock neigh->lock

   Reference count prevents destruction.

   neigh->lock mainly serializes ll address data and its validity state.
   However, the same lock is used to protect another entry fields:
    - timer
    - resolution queue

   Again, nothing clever shall be made under neigh->lock,
   the most complicated procedure, which we allow is dev->hard_header.
   It is supposed, that dev->hard_header is simplistic and does
   not make callbacks to neighbour tables.

   The last lock is neigh_tbl_lock. It is pure SMP lock, protecting
   list of neighbour tables. This list is used only in process context,
 */

static DEFINE_RWLOCK(neigh_tbl_lock);

static int neigh_blackhole(struct sk_buff *skb)
{
	kfree_skb(skb);
	return -ENETDOWN;
}

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static void neigh_cleanup_and_release(struct neighbour *neigh)
{
	if (neigh->parms->neigh_cleanup)
		neigh->parms->neigh_cleanup(neigh);

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	__neigh_notify(neigh, RTM_DELNEIGH, 0);
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	neigh_release(neigh);
}

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/*
 * It is random distribution in the interval (1/2)*base...(3/2)*base.
 * It corresponds to default IPv6 settings and is not overridable,
 * because it is really reasonable choice.
 */

unsigned long neigh_rand_reach_time(unsigned long base)
{
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	return base ? (net_random() % base) + (base >> 1) : 0;
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}
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EXPORT_SYMBOL(neigh_rand_reach_time);
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static int neigh_forced_gc(struct neigh_table *tbl)
{
	int shrunk = 0;
	int i;

	NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);

	write_lock_bh(&tbl->lock);
	for (i = 0; i <= tbl->hash_mask; i++) {
		struct neighbour *n, **np;

		np = &tbl->hash_buckets[i];
		while ((n = *np) != NULL) {
			/* Neighbour record may be discarded if:
			 * - nobody refers to it.
			 * - it is not permanent
			 */
			write_lock(&n->lock);
			if (atomic_read(&n->refcnt) == 1 &&
			    !(n->nud_state & NUD_PERMANENT)) {
				*np	= n->next;
				n->dead = 1;
				shrunk	= 1;
				write_unlock(&n->lock);
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				neigh_cleanup_and_release(n);
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				continue;
			}
			write_unlock(&n->lock);
			np = &n->next;
		}
	}

	tbl->last_flush = jiffies;

	write_unlock_bh(&tbl->lock);

	return shrunk;
}

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static void neigh_add_timer(struct neighbour *n, unsigned long when)
{
	neigh_hold(n);
	if (unlikely(mod_timer(&n->timer, when))) {
		printk("NEIGH: BUG, double timer add, state is %x\n",
		       n->nud_state);
		dump_stack();
	}
}

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static int neigh_del_timer(struct neighbour *n)
{
	if ((n->nud_state & NUD_IN_TIMER) &&
	    del_timer(&n->timer)) {
		neigh_release(n);
		return 1;
	}
	return 0;
}

static void pneigh_queue_purge(struct sk_buff_head *list)
{
	struct sk_buff *skb;

	while ((skb = skb_dequeue(list)) != NULL) {
		dev_put(skb->dev);
		kfree_skb(skb);
	}
}

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static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev)
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{
	int i;

	for (i = 0; i <= tbl->hash_mask; i++) {
		struct neighbour *n, **np = &tbl->hash_buckets[i];

		while ((n = *np) != NULL) {
			if (dev && n->dev != dev) {
				np = &n->next;
				continue;
			}
			*np = n->next;
			write_lock(&n->lock);
			neigh_del_timer(n);
			n->dead = 1;

			if (atomic_read(&n->refcnt) != 1) {
				/* The most unpleasant situation.
				   We must destroy neighbour entry,
				   but someone still uses it.

				   The destroy will be delayed until
				   the last user releases us, but
				   we must kill timers etc. and move
				   it to safe state.
				 */
				skb_queue_purge(&n->arp_queue);
				n->output = neigh_blackhole;
				if (n->nud_state & NUD_VALID)
					n->nud_state = NUD_NOARP;
				else
					n->nud_state = NUD_NONE;
				NEIGH_PRINTK2("neigh %p is stray.\n", n);
			}
			write_unlock(&n->lock);
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			neigh_cleanup_and_release(n);
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		}
	}
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}
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void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
{
	write_lock_bh(&tbl->lock);
	neigh_flush_dev(tbl, dev);
	write_unlock_bh(&tbl->lock);
}
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EXPORT_SYMBOL(neigh_changeaddr);
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int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
{
	write_lock_bh(&tbl->lock);
	neigh_flush_dev(tbl, dev);
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	pneigh_ifdown(tbl, dev);
	write_unlock_bh(&tbl->lock);

	del_timer_sync(&tbl->proxy_timer);
	pneigh_queue_purge(&tbl->proxy_queue);
	return 0;
}
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EXPORT_SYMBOL(neigh_ifdown);
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static struct neighbour *neigh_alloc(struct neigh_table *tbl)
{
	struct neighbour *n = NULL;
	unsigned long now = jiffies;
	int entries;

	entries = atomic_inc_return(&tbl->entries) - 1;
	if (entries >= tbl->gc_thresh3 ||
	    (entries >= tbl->gc_thresh2 &&
	     time_after(now, tbl->last_flush + 5 * HZ))) {
		if (!neigh_forced_gc(tbl) &&
		    entries >= tbl->gc_thresh3)
			goto out_entries;
	}

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	n = kmem_cache_zalloc(tbl->kmem_cachep, GFP_ATOMIC);
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	if (!n)
		goto out_entries;

	skb_queue_head_init(&n->arp_queue);
	rwlock_init(&n->lock);
	n->updated	  = n->used = now;
	n->nud_state	  = NUD_NONE;
	n->output	  = neigh_blackhole;
	n->parms	  = neigh_parms_clone(&tbl->parms);
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	setup_timer(&n->timer, neigh_timer_handler, (unsigned long)n);
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	NEIGH_CACHE_STAT_INC(tbl, allocs);
	n->tbl		  = tbl;
	atomic_set(&n->refcnt, 1);
	n->dead		  = 1;
out:
	return n;

out_entries:
	atomic_dec(&tbl->entries);
	goto out;
}

static struct neighbour **neigh_hash_alloc(unsigned int entries)
{
	unsigned long size = entries * sizeof(struct neighbour *);
	struct neighbour **ret;

	if (size <= PAGE_SIZE) {
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		ret = kzalloc(size, GFP_ATOMIC);
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	} else {
		ret = (struct neighbour **)
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		      __get_free_pages(GFP_ATOMIC|__GFP_ZERO, get_order(size));
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	}
	return ret;
}

static void neigh_hash_free(struct neighbour **hash, unsigned int entries)
{
	unsigned long size = entries * sizeof(struct neighbour *);

	if (size <= PAGE_SIZE)
		kfree(hash);
	else
		free_pages((unsigned long)hash, get_order(size));
}

static void neigh_hash_grow(struct neigh_table *tbl, unsigned long new_entries)
{
	struct neighbour **new_hash, **old_hash;
	unsigned int i, new_hash_mask, old_entries;

	NEIGH_CACHE_STAT_INC(tbl, hash_grows);

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	BUG_ON(!is_power_of_2(new_entries));
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	new_hash = neigh_hash_alloc(new_entries);
	if (!new_hash)
		return;

	old_entries = tbl->hash_mask + 1;
	new_hash_mask = new_entries - 1;
	old_hash = tbl->hash_buckets;

	get_random_bytes(&tbl->hash_rnd, sizeof(tbl->hash_rnd));
	for (i = 0; i < old_entries; i++) {
		struct neighbour *n, *next;

		for (n = old_hash[i]; n; n = next) {
			unsigned int hash_val = tbl->hash(n->primary_key, n->dev);

			hash_val &= new_hash_mask;
			next = n->next;

			n->next = new_hash[hash_val];
			new_hash[hash_val] = n;
		}
	}
	tbl->hash_buckets = new_hash;
	tbl->hash_mask = new_hash_mask;

	neigh_hash_free(old_hash, old_entries);
}

struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
			       struct net_device *dev)
{
	struct neighbour *n;
	int key_len = tbl->key_len;
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	u32 hash_val;
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	NEIGH_CACHE_STAT_INC(tbl, lookups);

	read_lock_bh(&tbl->lock);
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	hash_val = tbl->hash(pkey, dev);
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	for (n = tbl->hash_buckets[hash_val & tbl->hash_mask]; n; n = n->next) {
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		if (dev == n->dev && !memcmp(n->primary_key, pkey, key_len)) {
			neigh_hold(n);
			NEIGH_CACHE_STAT_INC(tbl, hits);
			break;
		}
	}
	read_unlock_bh(&tbl->lock);
	return n;
}
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EXPORT_SYMBOL(neigh_lookup);
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struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
				     const void *pkey)
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{
	struct neighbour *n;
	int key_len = tbl->key_len;
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	u32 hash_val;
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	NEIGH_CACHE_STAT_INC(tbl, lookups);

	read_lock_bh(&tbl->lock);
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	hash_val = tbl->hash(pkey, NULL);
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	for (n = tbl->hash_buckets[hash_val & tbl->hash_mask]; n; n = n->next) {
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		if (!memcmp(n->primary_key, pkey, key_len) &&
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		    net_eq(dev_net(n->dev), net)) {
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			neigh_hold(n);
			NEIGH_CACHE_STAT_INC(tbl, hits);
			break;
		}
	}
	read_unlock_bh(&tbl->lock);
	return n;
}
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EXPORT_SYMBOL(neigh_lookup_nodev);
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struct neighbour *neigh_create(struct neigh_table *tbl, const void *pkey,
			       struct net_device *dev)
{
	u32 hash_val;
	int key_len = tbl->key_len;
	int error;
	struct neighbour *n1, *rc, *n = neigh_alloc(tbl);

	if (!n) {
		rc = ERR_PTR(-ENOBUFS);
		goto out;
	}

	memcpy(n->primary_key, pkey, key_len);
	n->dev = dev;
	dev_hold(dev);

	/* Protocol specific setup. */
	if (tbl->constructor &&	(error = tbl->constructor(n)) < 0) {
		rc = ERR_PTR(error);
		goto out_neigh_release;
	}

	/* Device specific setup. */
	if (n->parms->neigh_setup &&
	    (error = n->parms->neigh_setup(n)) < 0) {
		rc = ERR_PTR(error);
		goto out_neigh_release;
	}

	n->confirmed = jiffies - (n->parms->base_reachable_time << 1);

	write_lock_bh(&tbl->lock);

	if (atomic_read(&tbl->entries) > (tbl->hash_mask + 1))
		neigh_hash_grow(tbl, (tbl->hash_mask + 1) << 1);

	hash_val = tbl->hash(pkey, dev) & tbl->hash_mask;

	if (n->parms->dead) {
		rc = ERR_PTR(-EINVAL);
		goto out_tbl_unlock;
	}

	for (n1 = tbl->hash_buckets[hash_val]; n1; n1 = n1->next) {
		if (dev == n1->dev && !memcmp(n1->primary_key, pkey, key_len)) {
			neigh_hold(n1);
			rc = n1;
			goto out_tbl_unlock;
		}
	}

	n->next = tbl->hash_buckets[hash_val];
	tbl->hash_buckets[hash_val] = n;
	n->dead = 0;
	neigh_hold(n);
	write_unlock_bh(&tbl->lock);
	NEIGH_PRINTK2("neigh %p is created.\n", n);
	rc = n;
out:
	return rc;
out_tbl_unlock:
	write_unlock_bh(&tbl->lock);
out_neigh_release:
	neigh_release(n);
	goto out;
}
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EXPORT_SYMBOL(neigh_create);
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static u32 pneigh_hash(const void *pkey, int key_len)
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{
	u32 hash_val = *(u32 *)(pkey + key_len - 4);
	hash_val ^= (hash_val >> 16);
	hash_val ^= hash_val >> 8;
	hash_val ^= hash_val >> 4;
	hash_val &= PNEIGH_HASHMASK;
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	return hash_val;
}
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static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n,
					      struct net *net,
					      const void *pkey,
					      int key_len,
					      struct net_device *dev)
{
	while (n) {
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		if (!memcmp(n->key, pkey, key_len) &&
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		    net_eq(pneigh_net(n), net) &&
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		    (n->dev == dev || !n->dev))
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			return n;
		n = n->next;
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	}
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	return NULL;
}
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struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
		struct net *net, const void *pkey, struct net_device *dev)
{
	int key_len = tbl->key_len;
	u32 hash_val = pneigh_hash(pkey, key_len);

	return __pneigh_lookup_1(tbl->phash_buckets[hash_val],
				 net, pkey, key_len, dev);
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}
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EXPORT_SYMBOL_GPL(__pneigh_lookup);
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struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
				    struct net *net, const void *pkey,
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				    struct net_device *dev, int creat)
{
	struct pneigh_entry *n;
	int key_len = tbl->key_len;
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	u32 hash_val = pneigh_hash(pkey, key_len);
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	read_lock_bh(&tbl->lock);
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	n = __pneigh_lookup_1(tbl->phash_buckets[hash_val],
			      net, pkey, key_len, dev);
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	read_unlock_bh(&tbl->lock);
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	if (n || !creat)
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		goto out;

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	ASSERT_RTNL();

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	n = kmalloc(sizeof(*n) + key_len, GFP_KERNEL);
	if (!n)
		goto out;

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	write_pnet(&n->net, hold_net(net));
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	memcpy(n->key, pkey, key_len);
	n->dev = dev;
	if (dev)
		dev_hold(dev);

	if (tbl->pconstructor && tbl->pconstructor(n)) {
		if (dev)
			dev_put(dev);
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		release_net(net);
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		kfree(n);
		n = NULL;
		goto out;
	}

	write_lock_bh(&tbl->lock);
	n->next = tbl->phash_buckets[hash_val];
	tbl->phash_buckets[hash_val] = n;
	write_unlock_bh(&tbl->lock);
out:
	return n;
}
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EXPORT_SYMBOL(pneigh_lookup);
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int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
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		  struct net_device *dev)
{
	struct pneigh_entry *n, **np;
	int key_len = tbl->key_len;
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	u32 hash_val = pneigh_hash(pkey, key_len);
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	write_lock_bh(&tbl->lock);
	for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
	     np = &n->next) {
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		if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
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		    net_eq(pneigh_net(n), net)) {
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			*np = n->next;
			write_unlock_bh(&tbl->lock);
			if (tbl->pdestructor)
				tbl->pdestructor(n);
			if (n->dev)
				dev_put(n->dev);
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			release_net(pneigh_net(n));
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			kfree(n);
			return 0;
		}
	}
	write_unlock_bh(&tbl->lock);
	return -ENOENT;
}

static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
{
	struct pneigh_entry *n, **np;
	u32 h;

	for (h = 0; h <= PNEIGH_HASHMASK; h++) {
		np = &tbl->phash_buckets[h];
		while ((n = *np) != NULL) {
			if (!dev || n->dev == dev) {
				*np = n->next;
				if (tbl->pdestructor)
					tbl->pdestructor(n);
				if (n->dev)
					dev_put(n->dev);
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				release_net(pneigh_net(n));
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				kfree(n);
				continue;
			}
			np = &n->next;
		}
	}
	return -ENOENT;
}

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static void neigh_parms_destroy(struct neigh_parms *parms);

static inline void neigh_parms_put(struct neigh_parms *parms)
{
	if (atomic_dec_and_test(&parms->refcnt))
		neigh_parms_destroy(parms);
}
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/*
 *	neighbour must already be out of the table;
 *
 */
void neigh_destroy(struct neighbour *neigh)
{
	struct hh_cache *hh;

	NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);

	if (!neigh->dead) {
		printk(KERN_WARNING
		       "Destroying alive neighbour %p\n", neigh);
		dump_stack();
		return;
	}

	if (neigh_del_timer(neigh))
		printk(KERN_WARNING "Impossible event.\n");

	while ((hh = neigh->hh) != NULL) {
		neigh->hh = hh->hh_next;
		hh->hh_next = NULL;
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		write_seqlock_bh(&hh->hh_lock);
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		hh->hh_output = neigh_blackhole;
645
		write_sequnlock_bh(&hh->hh_lock);
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		if (atomic_dec_and_test(&hh->hh_refcnt))
			kfree(hh);
	}

	skb_queue_purge(&neigh->arp_queue);

	dev_put(neigh->dev);
	neigh_parms_put(neigh->parms);

	NEIGH_PRINTK2("neigh %p is destroyed.\n", neigh);

	atomic_dec(&neigh->tbl->entries);
	kmem_cache_free(neigh->tbl->kmem_cachep, neigh);
}
660
EXPORT_SYMBOL(neigh_destroy);
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/* Neighbour state is suspicious;
   disable fast path.

   Called with write_locked neigh.
 */
static void neigh_suspect(struct neighbour *neigh)
{
	struct hh_cache *hh;

	NEIGH_PRINTK2("neigh %p is suspected.\n", neigh);

	neigh->output = neigh->ops->output;

	for (hh = neigh->hh; hh; hh = hh->hh_next)
		hh->hh_output = neigh->ops->output;
}

/* Neighbour state is OK;
   enable fast path.

   Called with write_locked neigh.
 */
static void neigh_connect(struct neighbour *neigh)
{
	struct hh_cache *hh;

	NEIGH_PRINTK2("neigh %p is connected.\n", neigh);

	neigh->output = neigh->ops->connected_output;

	for (hh = neigh->hh; hh; hh = hh->hh_next)
		hh->hh_output = neigh->ops->hh_output;
}

696
static void neigh_periodic_work(struct work_struct *work)
L
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{
698
	struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work);
L
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	struct neighbour *n, **np;
700
	unsigned int i;
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	NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);

704
	write_lock_bh(&tbl->lock);
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	/*
	 *	periodically recompute ReachableTime from random function
	 */

710
	if (time_after(jiffies, tbl->last_rand + 300 * HZ)) {
L
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711
		struct neigh_parms *p;
712
		tbl->last_rand = jiffies;
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		for (p = &tbl->parms; p; p = p->next)
			p->reachable_time =
				neigh_rand_reach_time(p->base_reachable_time);
	}

718 719
	for (i = 0 ; i <= tbl->hash_mask; i++) {
		np = &tbl->hash_buckets[i];
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721 722
		while ((n = *np) != NULL) {
			unsigned int state;
L
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723

724
			write_lock(&n->lock);
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726 727 728 729 730
			state = n->nud_state;
			if (state & (NUD_PERMANENT | NUD_IN_TIMER)) {
				write_unlock(&n->lock);
				goto next_elt;
			}
L
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731

732 733
			if (time_before(n->used, n->confirmed))
				n->used = n->confirmed;
L
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734

735 736 737 738 739 740 741 742 743
			if (atomic_read(&n->refcnt) == 1 &&
			    (state == NUD_FAILED ||
			     time_after(jiffies, n->used + n->parms->gc_staletime))) {
				*np = n->next;
				n->dead = 1;
				write_unlock(&n->lock);
				neigh_cleanup_and_release(n);
				continue;
			}
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			write_unlock(&n->lock);

next_elt:
747 748 749 750 751 752 753 754 755
			np = &n->next;
		}
		/*
		 * It's fine to release lock here, even if hash table
		 * grows while we are preempted.
		 */
		write_unlock_bh(&tbl->lock);
		cond_resched();
		write_lock_bh(&tbl->lock);
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	}
757 758 759
	/* Cycle through all hash buckets every base_reachable_time/2 ticks.
	 * ARP entry timeouts range from 1/2 base_reachable_time to 3/2
	 * base_reachable_time.
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	 */
761 762 763
	schedule_delayed_work(&tbl->gc_work,
			      tbl->parms.base_reachable_time >> 1);
	write_unlock_bh(&tbl->lock);
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}

static __inline__ int neigh_max_probes(struct neighbour *n)
{
	struct neigh_parms *p = n->parms;
E
Eric Dumazet 已提交
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	return (n->nud_state & NUD_PROBE) ?
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		p->ucast_probes :
E
Eric Dumazet 已提交
771
		p->ucast_probes + p->app_probes + p->mcast_probes;
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}

774
static void neigh_invalidate(struct neighbour *neigh)
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	__releases(neigh->lock)
	__acquires(neigh->lock)
777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797
{
	struct sk_buff *skb;

	NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
	NEIGH_PRINTK2("neigh %p is failed.\n", neigh);
	neigh->updated = jiffies;

	/* It is very thin place. report_unreachable is very complicated
	   routine. Particularly, it can hit the same neighbour entry!

	   So that, we try to be accurate and avoid dead loop. --ANK
	 */
	while (neigh->nud_state == NUD_FAILED &&
	       (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
		write_unlock(&neigh->lock);
		neigh->ops->error_report(neigh, skb);
		write_lock(&neigh->lock);
	}
	skb_queue_purge(&neigh->arp_queue);
}

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/* Called when a timer expires for a neighbour entry. */

static void neigh_timer_handler(unsigned long arg)
{
	unsigned long now, next;
	struct neighbour *neigh = (struct neighbour *)arg;
	unsigned state;
	int notify = 0;

	write_lock(&neigh->lock);

	state = neigh->nud_state;
	now = jiffies;
	next = now + HZ;

	if (!(state & NUD_IN_TIMER)) {
#ifndef CONFIG_SMP
		printk(KERN_WARNING "neigh: timer & !nud_in_timer\n");
#endif
		goto out;
	}

	if (state & NUD_REACHABLE) {
821
		if (time_before_eq(now,
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				   neigh->confirmed + neigh->parms->reachable_time)) {
			NEIGH_PRINTK2("neigh %p is still alive.\n", neigh);
			next = neigh->confirmed + neigh->parms->reachable_time;
		} else if (time_before_eq(now,
					  neigh->used + neigh->parms->delay_probe_time)) {
			NEIGH_PRINTK2("neigh %p is delayed.\n", neigh);
			neigh->nud_state = NUD_DELAY;
829
			neigh->updated = jiffies;
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			neigh_suspect(neigh);
			next = now + neigh->parms->delay_probe_time;
		} else {
			NEIGH_PRINTK2("neigh %p is suspected.\n", neigh);
			neigh->nud_state = NUD_STALE;
835
			neigh->updated = jiffies;
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			neigh_suspect(neigh);
837
			notify = 1;
L
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		}
	} else if (state & NUD_DELAY) {
840
		if (time_before_eq(now,
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				   neigh->confirmed + neigh->parms->delay_probe_time)) {
			NEIGH_PRINTK2("neigh %p is now reachable.\n", neigh);
			neigh->nud_state = NUD_REACHABLE;
844
			neigh->updated = jiffies;
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			neigh_connect(neigh);
846
			notify = 1;
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			next = neigh->confirmed + neigh->parms->reachable_time;
		} else {
			NEIGH_PRINTK2("neigh %p is probed.\n", neigh);
			neigh->nud_state = NUD_PROBE;
851
			neigh->updated = jiffies;
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			atomic_set(&neigh->probes, 0);
			next = now + neigh->parms->retrans_time;
		}
	} else {
		/* NUD_PROBE|NUD_INCOMPLETE */
		next = now + neigh->parms->retrans_time;
	}

	if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
	    atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
		neigh->nud_state = NUD_FAILED;
		notify = 1;
864
		neigh_invalidate(neigh);
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	}

	if (neigh->nud_state & NUD_IN_TIMER) {
		if (time_before(next, jiffies + HZ/2))
			next = jiffies + HZ/2;
870 871
		if (!mod_timer(&neigh->timer, next))
			neigh_hold(neigh);
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	}
	if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
		struct sk_buff *skb = skb_peek(&neigh->arp_queue);
875 876
		/* keep skb alive even if arp_queue overflows */
		if (skb)
877
			skb = skb_copy(skb, GFP_ATOMIC);
878
		write_unlock(&neigh->lock);
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879 880
		neigh->ops->solicit(neigh, skb);
		atomic_inc(&neigh->probes);
881
		kfree_skb(skb);
882
	} else {
883
out:
884 885
		write_unlock(&neigh->lock);
	}
T
Thomas Graf 已提交
886

887
	if (notify)
T
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888
		neigh_update_notify(neigh);
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889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904

	neigh_release(neigh);
}

int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
{
	int rc;
	unsigned long now;

	write_lock_bh(&neigh->lock);

	rc = 0;
	if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
		goto out_unlock_bh;

	now = jiffies;
905

L
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	if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
		if (neigh->parms->mcast_probes + neigh->parms->app_probes) {
			atomic_set(&neigh->probes, neigh->parms->ucast_probes);
			neigh->nud_state     = NUD_INCOMPLETE;
910
			neigh->updated = jiffies;
911
			neigh_add_timer(neigh, now + 1);
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		} else {
			neigh->nud_state = NUD_FAILED;
914
			neigh->updated = jiffies;
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915 916
			write_unlock_bh(&neigh->lock);

917
			kfree_skb(skb);
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			return 1;
		}
	} else if (neigh->nud_state & NUD_STALE) {
		NEIGH_PRINTK2("neigh %p is delayed.\n", neigh);
		neigh->nud_state = NUD_DELAY;
923
		neigh->updated = jiffies;
924 925
		neigh_add_timer(neigh,
				jiffies + neigh->parms->delay_probe_time);
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926 927 928 929 930 931 932
	}

	if (neigh->nud_state == NUD_INCOMPLETE) {
		if (skb) {
			if (skb_queue_len(&neigh->arp_queue) >=
			    neigh->parms->queue_len) {
				struct sk_buff *buff;
933
				buff = __skb_dequeue(&neigh->arp_queue);
L
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934
				kfree_skb(buff);
935
				NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
L
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936
			}
E
Eric Dumazet 已提交
937
			skb_dst_force(skb);
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938 939 940 941 942 943 944 945
			__skb_queue_tail(&neigh->arp_queue, skb);
		}
		rc = 1;
	}
out_unlock_bh:
	write_unlock_bh(&neigh->lock);
	return rc;
}
946
EXPORT_SYMBOL(__neigh_event_send);
L
Linus Torvalds 已提交
947

948
static void neigh_update_hhs(struct neighbour *neigh)
L
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949 950
{
	struct hh_cache *hh;
951
	void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
D
Doug Kehn 已提交
952 953 954 955
		= NULL;

	if (neigh->dev->header_ops)
		update = neigh->dev->header_ops->cache_update;
L
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956 957 958

	if (update) {
		for (hh = neigh->hh; hh; hh = hh->hh_next) {
959
			write_seqlock_bh(&hh->hh_lock);
L
Linus Torvalds 已提交
960
			update(hh, neigh->dev, neigh->ha);
961
			write_sequnlock_bh(&hh->hh_lock);
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962 963 964 965 966 967 968 969 970 971 972 973 974
		}
	}
}



/* Generic update routine.
   -- lladdr is new lladdr or NULL, if it is not supplied.
   -- new    is new state.
   -- flags
	NEIGH_UPDATE_F_OVERRIDE allows to override existing lladdr,
				if it is different.
	NEIGH_UPDATE_F_WEAK_OVERRIDE will suspect existing "connected"
975
				lladdr instead of overriding it
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				if it is different.
				It also allows to retain current state
				if lladdr is unchanged.
	NEIGH_UPDATE_F_ADMIN	means that the change is administrative.

981
	NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
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				NTF_ROUTER flag.
	NEIGH_UPDATE_F_ISROUTER	indicates if the neighbour is known as
				a router.

   Caller MUST hold reference count on the entry.
 */

int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
		 u32 flags)
{
	u8 old;
	int err;
	int notify = 0;
	struct net_device *dev;
	int update_isrouter = 0;

	write_lock_bh(&neigh->lock);

	dev    = neigh->dev;
	old    = neigh->nud_state;
	err    = -EPERM;

1004
	if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
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1005 1006 1007 1008 1009 1010 1011 1012 1013 1014
	    (old & (NUD_NOARP | NUD_PERMANENT)))
		goto out;

	if (!(new & NUD_VALID)) {
		neigh_del_timer(neigh);
		if (old & NUD_CONNECTED)
			neigh_suspect(neigh);
		neigh->nud_state = new;
		err = 0;
		notify = old & NUD_VALID;
1015 1016 1017 1018 1019
		if ((old & (NUD_INCOMPLETE | NUD_PROBE)) &&
		    (new & NUD_FAILED)) {
			neigh_invalidate(neigh);
			notify = 1;
		}
L
Linus Torvalds 已提交
1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032
		goto out;
	}

	/* Compare new lladdr with cached one */
	if (!dev->addr_len) {
		/* First case: device needs no address. */
		lladdr = neigh->ha;
	} else if (lladdr) {
		/* The second case: if something is already cached
		   and a new address is proposed:
		   - compare new & old
		   - if they are different, check override flag
		 */
1033
		if ((old & NUD_VALID) &&
L
Linus Torvalds 已提交
1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074
		    !memcmp(lladdr, neigh->ha, dev->addr_len))
			lladdr = neigh->ha;
	} else {
		/* No address is supplied; if we know something,
		   use it, otherwise discard the request.
		 */
		err = -EINVAL;
		if (!(old & NUD_VALID))
			goto out;
		lladdr = neigh->ha;
	}

	if (new & NUD_CONNECTED)
		neigh->confirmed = jiffies;
	neigh->updated = jiffies;

	/* If entry was valid and address is not changed,
	   do not change entry state, if new one is STALE.
	 */
	err = 0;
	update_isrouter = flags & NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
	if (old & NUD_VALID) {
		if (lladdr != neigh->ha && !(flags & NEIGH_UPDATE_F_OVERRIDE)) {
			update_isrouter = 0;
			if ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) &&
			    (old & NUD_CONNECTED)) {
				lladdr = neigh->ha;
				new = NUD_STALE;
			} else
				goto out;
		} else {
			if (lladdr == neigh->ha && new == NUD_STALE &&
			    ((flags & NEIGH_UPDATE_F_WEAK_OVERRIDE) ||
			     (old & NUD_CONNECTED))
			    )
				new = old;
		}
	}

	if (new != old) {
		neigh_del_timer(neigh);
1075
		if (new & NUD_IN_TIMER)
1076 1077
			neigh_add_timer(neigh, (jiffies +
						((new & NUD_REACHABLE) ?
1078 1079
						 neigh->parms->reachable_time :
						 0)));
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1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106
		neigh->nud_state = new;
	}

	if (lladdr != neigh->ha) {
		memcpy(&neigh->ha, lladdr, dev->addr_len);
		neigh_update_hhs(neigh);
		if (!(new & NUD_CONNECTED))
			neigh->confirmed = jiffies -
				      (neigh->parms->base_reachable_time << 1);
		notify = 1;
	}
	if (new == old)
		goto out;
	if (new & NUD_CONNECTED)
		neigh_connect(neigh);
	else
		neigh_suspect(neigh);
	if (!(old & NUD_VALID)) {
		struct sk_buff *skb;

		/* Again: avoid dead loop if something went wrong */

		while (neigh->nud_state & NUD_VALID &&
		       (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
			struct neighbour *n1 = neigh;
			write_unlock_bh(&neigh->lock);
			/* On shaper/eql skb->dst->neighbour != neigh :( */
E
Eric Dumazet 已提交
1107 1108
			if (skb_dst(skb) && skb_dst(skb)->neighbour)
				n1 = skb_dst(skb)->neighbour;
L
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1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120
			n1->output(skb);
			write_lock_bh(&neigh->lock);
		}
		skb_queue_purge(&neigh->arp_queue);
	}
out:
	if (update_isrouter) {
		neigh->flags = (flags & NEIGH_UPDATE_F_ISROUTER) ?
			(neigh->flags | NTF_ROUTER) :
			(neigh->flags & ~NTF_ROUTER);
	}
	write_unlock_bh(&neigh->lock);
1121 1122

	if (notify)
T
Thomas Graf 已提交
1123 1124
		neigh_update_notify(neigh);

L
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1125 1126
	return err;
}
1127
EXPORT_SYMBOL(neigh_update);
L
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1128 1129 1130 1131 1132 1133 1134 1135

struct neighbour *neigh_event_ns(struct neigh_table *tbl,
				 u8 *lladdr, void *saddr,
				 struct net_device *dev)
{
	struct neighbour *neigh = __neigh_lookup(tbl, saddr, dev,
						 lladdr || !dev->addr_len);
	if (neigh)
1136
		neigh_update(neigh, lladdr, NUD_STALE,
L
Linus Torvalds 已提交
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			     NEIGH_UPDATE_F_OVERRIDE);
	return neigh;
}
1140
EXPORT_SYMBOL(neigh_event_ns);
L
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1141 1142

static void neigh_hh_init(struct neighbour *n, struct dst_entry *dst,
A
Al Viro 已提交
1143
			  __be16 protocol)
L
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1144 1145 1146 1147 1148 1149 1150 1151
{
	struct hh_cache	*hh;
	struct net_device *dev = dst->dev;

	for (hh = n->hh; hh; hh = hh->hh_next)
		if (hh->hh_type == protocol)
			break;

A
Andrew Morton 已提交
1152
	if (!hh && (hh = kzalloc(sizeof(*hh), GFP_ATOMIC)) != NULL) {
1153
		seqlock_init(&hh->hh_lock);
L
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1154 1155 1156
		hh->hh_type = protocol;
		atomic_set(&hh->hh_refcnt, 0);
		hh->hh_next = NULL;
1157 1158

		if (dev->header_ops->cache(n, hh)) {
L
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			kfree(hh);
			hh = NULL;
		} else {
			atomic_inc(&hh->hh_refcnt);
			hh->hh_next = n->hh;
			n->hh	    = hh;
			if (n->nud_state & NUD_CONNECTED)
				hh->hh_output = n->ops->hh_output;
			else
				hh->hh_output = n->ops->output;
		}
	}
	if (hh)	{
		atomic_inc(&hh->hh_refcnt);
		dst->hh = hh;
	}
}

/* This function can be used in contexts, where only old dev_queue_xmit
   worked, f.e. if you want to override normal output path (eql, shaper),
   but resolution is not made yet.
 */

int neigh_compat_output(struct sk_buff *skb)
{
	struct net_device *dev = skb->dev;

1186
	__skb_pull(skb, skb_network_offset(skb));
L
Linus Torvalds 已提交
1187

1188 1189
	if (dev_hard_header(skb, dev, ntohs(skb->protocol), NULL, NULL,
			    skb->len) < 0 &&
1190
	    dev->header_ops->rebuild(skb))
L
Linus Torvalds 已提交
1191 1192 1193 1194
		return 0;

	return dev_queue_xmit(skb);
}
1195
EXPORT_SYMBOL(neigh_compat_output);
L
Linus Torvalds 已提交
1196 1197 1198 1199 1200

/* Slow and careful. */

int neigh_resolve_output(struct sk_buff *skb)
{
E
Eric Dumazet 已提交
1201
	struct dst_entry *dst = skb_dst(skb);
L
Linus Torvalds 已提交
1202 1203 1204 1205 1206 1207
	struct neighbour *neigh;
	int rc = 0;

	if (!dst || !(neigh = dst->neighbour))
		goto discard;

1208
	__skb_pull(skb, skb_network_offset(skb));
L
Linus Torvalds 已提交
1209 1210 1211 1212

	if (!neigh_event_send(neigh, skb)) {
		int err;
		struct net_device *dev = neigh->dev;
E
Eric Dumazet 已提交
1213 1214 1215
		if (dev->header_ops->cache &&
		    !dst->hh &&
		    !(dst->flags & DST_NOCACHE)) {
L
Linus Torvalds 已提交
1216 1217 1218
			write_lock_bh(&neigh->lock);
			if (!dst->hh)
				neigh_hh_init(neigh, dst, dst->ops->protocol);
1219 1220
			err = dev_hard_header(skb, dev, ntohs(skb->protocol),
					      neigh->ha, NULL, skb->len);
L
Linus Torvalds 已提交
1221 1222 1223
			write_unlock_bh(&neigh->lock);
		} else {
			read_lock_bh(&neigh->lock);
1224 1225
			err = dev_hard_header(skb, dev, ntohs(skb->protocol),
					      neigh->ha, NULL, skb->len);
L
Linus Torvalds 已提交
1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242
			read_unlock_bh(&neigh->lock);
		}
		if (err >= 0)
			rc = neigh->ops->queue_xmit(skb);
		else
			goto out_kfree_skb;
	}
out:
	return rc;
discard:
	NEIGH_PRINTK1("neigh_resolve_output: dst=%p neigh=%p\n",
		      dst, dst ? dst->neighbour : NULL);
out_kfree_skb:
	rc = -EINVAL;
	kfree_skb(skb);
	goto out;
}
1243
EXPORT_SYMBOL(neigh_resolve_output);
L
Linus Torvalds 已提交
1244 1245 1246 1247 1248 1249

/* As fast as possible without hh cache */

int neigh_connected_output(struct sk_buff *skb)
{
	int err;
E
Eric Dumazet 已提交
1250
	struct dst_entry *dst = skb_dst(skb);
L
Linus Torvalds 已提交
1251 1252 1253
	struct neighbour *neigh = dst->neighbour;
	struct net_device *dev = neigh->dev;

1254
	__skb_pull(skb, skb_network_offset(skb));
L
Linus Torvalds 已提交
1255 1256

	read_lock_bh(&neigh->lock);
1257 1258
	err = dev_hard_header(skb, dev, ntohs(skb->protocol),
			      neigh->ha, NULL, skb->len);
L
Linus Torvalds 已提交
1259 1260 1261 1262 1263 1264 1265 1266 1267
	read_unlock_bh(&neigh->lock);
	if (err >= 0)
		err = neigh->ops->queue_xmit(skb);
	else {
		err = -EINVAL;
		kfree_skb(skb);
	}
	return err;
}
1268
EXPORT_SYMBOL(neigh_connected_output);
L
Linus Torvalds 已提交
1269 1270 1271 1272 1273 1274

static void neigh_proxy_process(unsigned long arg)
{
	struct neigh_table *tbl = (struct neigh_table *)arg;
	long sched_next = 0;
	unsigned long now = jiffies;
1275
	struct sk_buff *skb, *n;
L
Linus Torvalds 已提交
1276 1277 1278

	spin_lock(&tbl->proxy_queue.lock);

1279 1280
	skb_queue_walk_safe(&tbl->proxy_queue, skb, n) {
		long tdif = NEIGH_CB(skb)->sched_next - now;
L
Linus Torvalds 已提交
1281 1282

		if (tdif <= 0) {
1283 1284
			struct net_device *dev = skb->dev;
			__skb_unlink(skb, &tbl->proxy_queue);
L
Linus Torvalds 已提交
1285
			if (tbl->proxy_redo && netif_running(dev))
1286
				tbl->proxy_redo(skb);
L
Linus Torvalds 已提交
1287
			else
1288
				kfree_skb(skb);
L
Linus Torvalds 已提交
1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309

			dev_put(dev);
		} else if (!sched_next || tdif < sched_next)
			sched_next = tdif;
	}
	del_timer(&tbl->proxy_timer);
	if (sched_next)
		mod_timer(&tbl->proxy_timer, jiffies + sched_next);
	spin_unlock(&tbl->proxy_queue.lock);
}

void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
		    struct sk_buff *skb)
{
	unsigned long now = jiffies;
	unsigned long sched_next = now + (net_random() % p->proxy_delay);

	if (tbl->proxy_queue.qlen > p->proxy_qlen) {
		kfree_skb(skb);
		return;
	}
1310 1311 1312

	NEIGH_CB(skb)->sched_next = sched_next;
	NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
L
Linus Torvalds 已提交
1313 1314 1315 1316 1317 1318

	spin_lock(&tbl->proxy_queue.lock);
	if (del_timer(&tbl->proxy_timer)) {
		if (time_before(tbl->proxy_timer.expires, sched_next))
			sched_next = tbl->proxy_timer.expires;
	}
E
Eric Dumazet 已提交
1319
	skb_dst_drop(skb);
L
Linus Torvalds 已提交
1320 1321 1322 1323 1324
	dev_hold(skb->dev);
	__skb_queue_tail(&tbl->proxy_queue, skb);
	mod_timer(&tbl->proxy_timer, sched_next);
	spin_unlock(&tbl->proxy_queue.lock);
}
1325
EXPORT_SYMBOL(pneigh_enqueue);
L
Linus Torvalds 已提交
1326

1327
static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl,
1328 1329 1330 1331 1332
						      struct net *net, int ifindex)
{
	struct neigh_parms *p;

	for (p = &tbl->parms; p; p = p->next) {
1333
		if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
1334 1335 1336 1337 1338 1339
		    (!p->dev && !ifindex))
			return p;
	}

	return NULL;
}
L
Linus Torvalds 已提交
1340 1341 1342 1343

struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
				      struct neigh_table *tbl)
{
1344
	struct neigh_parms *p, *ref;
1345 1346
	struct net *net = dev_net(dev);
	const struct net_device_ops *ops = dev->netdev_ops;
1347

1348
	ref = lookup_neigh_parms(tbl, net, 0);
1349 1350
	if (!ref)
		return NULL;
L
Linus Torvalds 已提交
1351

1352
	p = kmemdup(ref, sizeof(*p), GFP_KERNEL);
L
Linus Torvalds 已提交
1353 1354 1355 1356 1357
	if (p) {
		p->tbl		  = tbl;
		atomic_set(&p->refcnt, 1);
		p->reachable_time =
				neigh_rand_reach_time(p->base_reachable_time);
1358

1359
		if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) {
1360 1361
			kfree(p);
			return NULL;
L
Linus Torvalds 已提交
1362
		}
1363 1364 1365

		dev_hold(dev);
		p->dev = dev;
E
Eric Dumazet 已提交
1366
		write_pnet(&p->net, hold_net(net));
L
Linus Torvalds 已提交
1367 1368 1369 1370 1371 1372 1373 1374
		p->sysctl_table = NULL;
		write_lock_bh(&tbl->lock);
		p->next		= tbl->parms.next;
		tbl->parms.next = p;
		write_unlock_bh(&tbl->lock);
	}
	return p;
}
1375
EXPORT_SYMBOL(neigh_parms_alloc);
L
Linus Torvalds 已提交
1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396

static void neigh_rcu_free_parms(struct rcu_head *head)
{
	struct neigh_parms *parms =
		container_of(head, struct neigh_parms, rcu_head);

	neigh_parms_put(parms);
}

void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms)
{
	struct neigh_parms **p;

	if (!parms || parms == &tbl->parms)
		return;
	write_lock_bh(&tbl->lock);
	for (p = &tbl->parms.next; *p; p = &(*p)->next) {
		if (*p == parms) {
			*p = parms->next;
			parms->dead = 1;
			write_unlock_bh(&tbl->lock);
1397 1398
			if (parms->dev)
				dev_put(parms->dev);
L
Linus Torvalds 已提交
1399 1400 1401 1402 1403 1404 1405
			call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
			return;
		}
	}
	write_unlock_bh(&tbl->lock);
	NEIGH_PRINTK1("neigh_parms_release: not found\n");
}
1406
EXPORT_SYMBOL(neigh_parms_release);
L
Linus Torvalds 已提交
1407

1408
static void neigh_parms_destroy(struct neigh_parms *parms)
L
Linus Torvalds 已提交
1409
{
1410
	release_net(neigh_parms_net(parms));
L
Linus Torvalds 已提交
1411 1412 1413
	kfree(parms);
}

1414 1415
static struct lock_class_key neigh_table_proxy_queue_class;

1416
void neigh_table_init_no_netlink(struct neigh_table *tbl)
L
Linus Torvalds 已提交
1417 1418 1419 1420
{
	unsigned long now = jiffies;
	unsigned long phsize;

E
Eric Dumazet 已提交
1421
	write_pnet(&tbl->parms.net, &init_net);
L
Linus Torvalds 已提交
1422 1423 1424 1425 1426
	atomic_set(&tbl->parms.refcnt, 1);
	tbl->parms.reachable_time =
			  neigh_rand_reach_time(tbl->parms.base_reachable_time);

	if (!tbl->kmem_cachep)
A
Alexey Dobriyan 已提交
1427 1428 1429
		tbl->kmem_cachep =
			kmem_cache_create(tbl->id, tbl->entry_size, 0,
					  SLAB_HWCACHE_ALIGN|SLAB_PANIC,
1430
					  NULL);
L
Linus Torvalds 已提交
1431 1432 1433
	tbl->stats = alloc_percpu(struct neigh_statistics);
	if (!tbl->stats)
		panic("cannot create neighbour cache statistics");
1434

L
Linus Torvalds 已提交
1435
#ifdef CONFIG_PROC_FS
1436 1437
	if (!proc_create_data(tbl->id, 0, init_net.proc_net_stat,
			      &neigh_stat_seq_fops, tbl))
L
Linus Torvalds 已提交
1438 1439 1440 1441 1442 1443 1444
		panic("cannot create neighbour proc dir entry");
#endif

	tbl->hash_mask = 1;
	tbl->hash_buckets = neigh_hash_alloc(tbl->hash_mask + 1);

	phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
A
Andrew Morton 已提交
1445
	tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
L
Linus Torvalds 已提交
1446 1447 1448 1449 1450 1451 1452

	if (!tbl->hash_buckets || !tbl->phash_buckets)
		panic("cannot allocate neighbour cache hashes");

	get_random_bytes(&tbl->hash_rnd, sizeof(tbl->hash_rnd));

	rwlock_init(&tbl->lock);
1453 1454
	INIT_DELAYED_WORK_DEFERRABLE(&tbl->gc_work, neigh_periodic_work);
	schedule_delayed_work(&tbl->gc_work, tbl->parms.reachable_time);
1455
	setup_timer(&tbl->proxy_timer, neigh_proxy_process, (unsigned long)tbl);
1456 1457
	skb_queue_head_init_class(&tbl->proxy_queue,
			&neigh_table_proxy_queue_class);
L
Linus Torvalds 已提交
1458 1459 1460

	tbl->last_flush = now;
	tbl->last_rand	= now + tbl->parms.reachable_time * 20;
1461
}
1462
EXPORT_SYMBOL(neigh_table_init_no_netlink);
1463 1464 1465 1466 1467 1468

void neigh_table_init(struct neigh_table *tbl)
{
	struct neigh_table *tmp;

	neigh_table_init_no_netlink(tbl);
L
Linus Torvalds 已提交
1469
	write_lock(&neigh_tbl_lock);
1470 1471 1472 1473
	for (tmp = neigh_tables; tmp; tmp = tmp->next) {
		if (tmp->family == tbl->family)
			break;
	}
L
Linus Torvalds 已提交
1474 1475 1476
	tbl->next	= neigh_tables;
	neigh_tables	= tbl;
	write_unlock(&neigh_tbl_lock);
1477 1478 1479 1480 1481 1482

	if (unlikely(tmp)) {
		printk(KERN_ERR "NEIGH: Registering multiple tables for "
		       "family %d\n", tbl->family);
		dump_stack();
	}
L
Linus Torvalds 已提交
1483
}
1484
EXPORT_SYMBOL(neigh_table_init);
L
Linus Torvalds 已提交
1485 1486 1487 1488 1489 1490

int neigh_table_clear(struct neigh_table *tbl)
{
	struct neigh_table **tp;

	/* It is not clean... Fix it to unload IPv6 module safely */
1491 1492
	cancel_delayed_work(&tbl->gc_work);
	flush_scheduled_work();
L
Linus Torvalds 已提交
1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512
	del_timer_sync(&tbl->proxy_timer);
	pneigh_queue_purge(&tbl->proxy_queue);
	neigh_ifdown(tbl, NULL);
	if (atomic_read(&tbl->entries))
		printk(KERN_CRIT "neighbour leakage\n");
	write_lock(&neigh_tbl_lock);
	for (tp = &neigh_tables; *tp; tp = &(*tp)->next) {
		if (*tp == tbl) {
			*tp = tbl->next;
			break;
		}
	}
	write_unlock(&neigh_tbl_lock);

	neigh_hash_free(tbl->hash_buckets, tbl->hash_mask + 1);
	tbl->hash_buckets = NULL;

	kfree(tbl->phash_buckets);
	tbl->phash_buckets = NULL;

1513 1514
	remove_proc_entry(tbl->id, init_net.proc_net_stat);

1515 1516 1517
	free_percpu(tbl->stats);
	tbl->stats = NULL;

1518 1519 1520
	kmem_cache_destroy(tbl->kmem_cachep);
	tbl->kmem_cachep = NULL;

L
Linus Torvalds 已提交
1521 1522
	return 0;
}
1523
EXPORT_SYMBOL(neigh_table_clear);
L
Linus Torvalds 已提交
1524

1525
static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
L
Linus Torvalds 已提交
1526
{
1527
	struct net *net = sock_net(skb->sk);
1528 1529
	struct ndmsg *ndm;
	struct nlattr *dst_attr;
L
Linus Torvalds 已提交
1530 1531
	struct neigh_table *tbl;
	struct net_device *dev = NULL;
1532
	int err = -EINVAL;
L
Linus Torvalds 已提交
1533

1534
	ASSERT_RTNL();
1535
	if (nlmsg_len(nlh) < sizeof(*ndm))
L
Linus Torvalds 已提交
1536 1537
		goto out;

1538 1539 1540 1541 1542 1543
	dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
	if (dst_attr == NULL)
		goto out;

	ndm = nlmsg_data(nlh);
	if (ndm->ndm_ifindex) {
1544
		dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1545 1546 1547 1548 1549 1550
		if (dev == NULL) {
			err = -ENODEV;
			goto out;
		}
	}

L
Linus Torvalds 已提交
1551 1552
	read_lock(&neigh_tbl_lock);
	for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1553
		struct neighbour *neigh;
L
Linus Torvalds 已提交
1554 1555 1556 1557 1558

		if (tbl->family != ndm->ndm_family)
			continue;
		read_unlock(&neigh_tbl_lock);

1559
		if (nla_len(dst_attr) < tbl->key_len)
1560
			goto out;
L
Linus Torvalds 已提交
1561 1562

		if (ndm->ndm_flags & NTF_PROXY) {
1563
			err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
1564
			goto out;
L
Linus Torvalds 已提交
1565 1566
		}

1567
		if (dev == NULL)
1568
			goto out;
L
Linus Torvalds 已提交
1569

1570 1571 1572
		neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
		if (neigh == NULL) {
			err = -ENOENT;
1573
			goto out;
L
Linus Torvalds 已提交
1574
		}
1575 1576 1577 1578 1579

		err = neigh_update(neigh, NULL, NUD_FAILED,
				   NEIGH_UPDATE_F_OVERRIDE |
				   NEIGH_UPDATE_F_ADMIN);
		neigh_release(neigh);
1580
		goto out;
L
Linus Torvalds 已提交
1581 1582
	}
	read_unlock(&neigh_tbl_lock);
1583 1584
	err = -EAFNOSUPPORT;

L
Linus Torvalds 已提交
1585 1586 1587 1588
out:
	return err;
}

1589
static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
L
Linus Torvalds 已提交
1590
{
1591
	struct net *net = sock_net(skb->sk);
1592 1593
	struct ndmsg *ndm;
	struct nlattr *tb[NDA_MAX+1];
L
Linus Torvalds 已提交
1594 1595
	struct neigh_table *tbl;
	struct net_device *dev = NULL;
1596
	int err;
L
Linus Torvalds 已提交
1597

1598
	ASSERT_RTNL();
1599 1600
	err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, NULL);
	if (err < 0)
L
Linus Torvalds 已提交
1601 1602
		goto out;

1603 1604 1605 1606 1607 1608
	err = -EINVAL;
	if (tb[NDA_DST] == NULL)
		goto out;

	ndm = nlmsg_data(nlh);
	if (ndm->ndm_ifindex) {
1609
		dev = __dev_get_by_index(net, ndm->ndm_ifindex);
1610 1611 1612 1613 1614 1615
		if (dev == NULL) {
			err = -ENODEV;
			goto out;
		}

		if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len)
1616
			goto out;
1617 1618
	}

L
Linus Torvalds 已提交
1619 1620
	read_lock(&neigh_tbl_lock);
	for (tbl = neigh_tables; tbl; tbl = tbl->next) {
1621 1622 1623
		int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE;
		struct neighbour *neigh;
		void *dst, *lladdr;
L
Linus Torvalds 已提交
1624 1625 1626 1627 1628

		if (tbl->family != ndm->ndm_family)
			continue;
		read_unlock(&neigh_tbl_lock);

1629
		if (nla_len(tb[NDA_DST]) < tbl->key_len)
1630
			goto out;
1631 1632
		dst = nla_data(tb[NDA_DST]);
		lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
L
Linus Torvalds 已提交
1633 1634

		if (ndm->ndm_flags & NTF_PROXY) {
1635 1636 1637
			struct pneigh_entry *pn;

			err = -ENOBUFS;
1638
			pn = pneigh_lookup(tbl, net, dst, dev, 1);
1639 1640 1641 1642
			if (pn) {
				pn->flags = ndm->ndm_flags;
				err = 0;
			}
1643
			goto out;
L
Linus Torvalds 已提交
1644 1645
		}

1646
		if (dev == NULL)
1647
			goto out;
1648 1649 1650 1651 1652

		neigh = neigh_lookup(tbl, dst, dev);
		if (neigh == NULL) {
			if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
				err = -ENOENT;
1653
				goto out;
1654
			}
1655

1656 1657 1658
			neigh = __neigh_lookup_errno(tbl, dst, dev);
			if (IS_ERR(neigh)) {
				err = PTR_ERR(neigh);
1659
				goto out;
L
Linus Torvalds 已提交
1660 1661
			}
		} else {
1662 1663 1664
			if (nlh->nlmsg_flags & NLM_F_EXCL) {
				err = -EEXIST;
				neigh_release(neigh);
1665
				goto out;
L
Linus Torvalds 已提交
1666 1667
			}

1668 1669 1670
			if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
				flags &= ~NEIGH_UPDATE_F_OVERRIDE;
		}
L
Linus Torvalds 已提交
1671

1672 1673 1674 1675 1676
		if (ndm->ndm_flags & NTF_USE) {
			neigh_event_send(neigh, NULL);
			err = 0;
		} else
			err = neigh_update(neigh, lladdr, ndm->ndm_state, flags);
1677
		neigh_release(neigh);
1678
		goto out;
L
Linus Torvalds 已提交
1679 1680 1681
	}

	read_unlock(&neigh_tbl_lock);
1682
	err = -EAFNOSUPPORT;
L
Linus Torvalds 已提交
1683 1684 1685 1686
out:
	return err;
}

1687 1688
static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
{
1689 1690 1691 1692 1693
	struct nlattr *nest;

	nest = nla_nest_start(skb, NDTA_PARMS);
	if (nest == NULL)
		return -ENOBUFS;
1694 1695

	if (parms->dev)
1696 1697 1698 1699 1700 1701 1702 1703 1704 1705
		NLA_PUT_U32(skb, NDTPA_IFINDEX, parms->dev->ifindex);

	NLA_PUT_U32(skb, NDTPA_REFCNT, atomic_read(&parms->refcnt));
	NLA_PUT_U32(skb, NDTPA_QUEUE_LEN, parms->queue_len);
	NLA_PUT_U32(skb, NDTPA_PROXY_QLEN, parms->proxy_qlen);
	NLA_PUT_U32(skb, NDTPA_APP_PROBES, parms->app_probes);
	NLA_PUT_U32(skb, NDTPA_UCAST_PROBES, parms->ucast_probes);
	NLA_PUT_U32(skb, NDTPA_MCAST_PROBES, parms->mcast_probes);
	NLA_PUT_MSECS(skb, NDTPA_REACHABLE_TIME, parms->reachable_time);
	NLA_PUT_MSECS(skb, NDTPA_BASE_REACHABLE_TIME,
1706
		      parms->base_reachable_time);
1707 1708 1709 1710 1711 1712
	NLA_PUT_MSECS(skb, NDTPA_GC_STALETIME, parms->gc_staletime);
	NLA_PUT_MSECS(skb, NDTPA_DELAY_PROBE_TIME, parms->delay_probe_time);
	NLA_PUT_MSECS(skb, NDTPA_RETRANS_TIME, parms->retrans_time);
	NLA_PUT_MSECS(skb, NDTPA_ANYCAST_DELAY, parms->anycast_delay);
	NLA_PUT_MSECS(skb, NDTPA_PROXY_DELAY, parms->proxy_delay);
	NLA_PUT_MSECS(skb, NDTPA_LOCKTIME, parms->locktime);
1713

1714
	return nla_nest_end(skb, nest);
1715

1716
nla_put_failure:
1717 1718
	nla_nest_cancel(skb, nest);
	return -EMSGSIZE;
1719 1720
}

1721 1722
static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
			      u32 pid, u32 seq, int type, int flags)
1723 1724 1725 1726
{
	struct nlmsghdr *nlh;
	struct ndtmsg *ndtmsg;

1727 1728
	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
	if (nlh == NULL)
1729
		return -EMSGSIZE;
1730

1731
	ndtmsg = nlmsg_data(nlh);
1732 1733 1734

	read_lock_bh(&tbl->lock);
	ndtmsg->ndtm_family = tbl->family;
1735 1736
	ndtmsg->ndtm_pad1   = 0;
	ndtmsg->ndtm_pad2   = 0;
1737

1738 1739 1740 1741 1742
	NLA_PUT_STRING(skb, NDTA_NAME, tbl->id);
	NLA_PUT_MSECS(skb, NDTA_GC_INTERVAL, tbl->gc_interval);
	NLA_PUT_U32(skb, NDTA_THRESH1, tbl->gc_thresh1);
	NLA_PUT_U32(skb, NDTA_THRESH2, tbl->gc_thresh2);
	NLA_PUT_U32(skb, NDTA_THRESH3, tbl->gc_thresh3);
1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759

	{
		unsigned long now = jiffies;
		unsigned int flush_delta = now - tbl->last_flush;
		unsigned int rand_delta = now - tbl->last_rand;

		struct ndt_config ndc = {
			.ndtc_key_len		= tbl->key_len,
			.ndtc_entry_size	= tbl->entry_size,
			.ndtc_entries		= atomic_read(&tbl->entries),
			.ndtc_last_flush	= jiffies_to_msecs(flush_delta),
			.ndtc_last_rand		= jiffies_to_msecs(rand_delta),
			.ndtc_hash_rnd		= tbl->hash_rnd,
			.ndtc_hash_mask		= tbl->hash_mask,
			.ndtc_proxy_qlen	= tbl->proxy_queue.qlen,
		};

1760
		NLA_PUT(skb, NDTA_CONFIG, sizeof(ndc), &ndc);
1761 1762 1763 1764 1765 1766 1767 1768
	}

	{
		int cpu;
		struct ndt_stats ndst;

		memset(&ndst, 0, sizeof(ndst));

1769
		for_each_possible_cpu(cpu) {
1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784
			struct neigh_statistics	*st;

			st = per_cpu_ptr(tbl->stats, cpu);
			ndst.ndts_allocs		+= st->allocs;
			ndst.ndts_destroys		+= st->destroys;
			ndst.ndts_hash_grows		+= st->hash_grows;
			ndst.ndts_res_failed		+= st->res_failed;
			ndst.ndts_lookups		+= st->lookups;
			ndst.ndts_hits			+= st->hits;
			ndst.ndts_rcv_probes_mcast	+= st->rcv_probes_mcast;
			ndst.ndts_rcv_probes_ucast	+= st->rcv_probes_ucast;
			ndst.ndts_periodic_gc_runs	+= st->periodic_gc_runs;
			ndst.ndts_forced_gc_runs	+= st->forced_gc_runs;
		}

1785
		NLA_PUT(skb, NDTA_STATS, sizeof(ndst), &ndst);
1786 1787 1788 1789
	}

	BUG_ON(tbl->parms.dev);
	if (neightbl_fill_parms(skb, &tbl->parms) < 0)
1790
		goto nla_put_failure;
1791 1792

	read_unlock_bh(&tbl->lock);
1793
	return nlmsg_end(skb, nlh);
1794

1795
nla_put_failure:
1796
	read_unlock_bh(&tbl->lock);
1797 1798
	nlmsg_cancel(skb, nlh);
	return -EMSGSIZE;
1799 1800
}

1801 1802
static int neightbl_fill_param_info(struct sk_buff *skb,
				    struct neigh_table *tbl,
1803
				    struct neigh_parms *parms,
1804 1805
				    u32 pid, u32 seq, int type,
				    unsigned int flags)
1806 1807 1808 1809
{
	struct ndtmsg *ndtmsg;
	struct nlmsghdr *nlh;

1810 1811
	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
	if (nlh == NULL)
1812
		return -EMSGSIZE;
1813

1814
	ndtmsg = nlmsg_data(nlh);
1815 1816 1817

	read_lock_bh(&tbl->lock);
	ndtmsg->ndtm_family = tbl->family;
1818 1819
	ndtmsg->ndtm_pad1   = 0;
	ndtmsg->ndtm_pad2   = 0;
1820

1821 1822 1823
	if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
	    neightbl_fill_parms(skb, parms) < 0)
		goto errout;
1824 1825

	read_unlock_bh(&tbl->lock);
1826 1827
	return nlmsg_end(skb, nlh);
errout:
1828
	read_unlock_bh(&tbl->lock);
1829 1830
	nlmsg_cancel(skb, nlh);
	return -EMSGSIZE;
1831
}
1832

1833
static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
1834 1835 1836 1837 1838 1839 1840 1841
	[NDTA_NAME]		= { .type = NLA_STRING },
	[NDTA_THRESH1]		= { .type = NLA_U32 },
	[NDTA_THRESH2]		= { .type = NLA_U32 },
	[NDTA_THRESH3]		= { .type = NLA_U32 },
	[NDTA_GC_INTERVAL]	= { .type = NLA_U64 },
	[NDTA_PARMS]		= { .type = NLA_NESTED },
};

1842
static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857
	[NDTPA_IFINDEX]			= { .type = NLA_U32 },
	[NDTPA_QUEUE_LEN]		= { .type = NLA_U32 },
	[NDTPA_PROXY_QLEN]		= { .type = NLA_U32 },
	[NDTPA_APP_PROBES]		= { .type = NLA_U32 },
	[NDTPA_UCAST_PROBES]		= { .type = NLA_U32 },
	[NDTPA_MCAST_PROBES]		= { .type = NLA_U32 },
	[NDTPA_BASE_REACHABLE_TIME]	= { .type = NLA_U64 },
	[NDTPA_GC_STALETIME]		= { .type = NLA_U64 },
	[NDTPA_DELAY_PROBE_TIME]	= { .type = NLA_U64 },
	[NDTPA_RETRANS_TIME]		= { .type = NLA_U64 },
	[NDTPA_ANYCAST_DELAY]		= { .type = NLA_U64 },
	[NDTPA_PROXY_DELAY]		= { .type = NLA_U64 },
	[NDTPA_LOCKTIME]		= { .type = NLA_U64 },
};

1858
static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1859
{
1860
	struct net *net = sock_net(skb->sk);
1861
	struct neigh_table *tbl;
1862 1863 1864
	struct ndtmsg *ndtmsg;
	struct nlattr *tb[NDTA_MAX+1];
	int err;
1865

1866 1867 1868 1869
	err = nlmsg_parse(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
			  nl_neightbl_policy);
	if (err < 0)
		goto errout;
1870

1871 1872 1873 1874 1875 1876
	if (tb[NDTA_NAME] == NULL) {
		err = -EINVAL;
		goto errout;
	}

	ndtmsg = nlmsg_data(nlh);
1877 1878 1879 1880 1881
	read_lock(&neigh_tbl_lock);
	for (tbl = neigh_tables; tbl; tbl = tbl->next) {
		if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
			continue;

1882
		if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0)
1883 1884 1885 1886 1887
			break;
	}

	if (tbl == NULL) {
		err = -ENOENT;
1888
		goto errout_locked;
1889 1890
	}

1891
	/*
1892 1893 1894 1895 1896
	 * We acquire tbl->lock to be nice to the periodic timers and
	 * make sure they always see a consistent set of values.
	 */
	write_lock_bh(&tbl->lock);

1897 1898
	if (tb[NDTA_PARMS]) {
		struct nlattr *tbp[NDTPA_MAX+1];
1899
		struct neigh_parms *p;
1900
		int i, ifindex = 0;
1901

1902 1903 1904 1905
		err = nla_parse_nested(tbp, NDTPA_MAX, tb[NDTA_PARMS],
				       nl_ntbl_parm_policy);
		if (err < 0)
			goto errout_tbl_lock;
1906

1907 1908
		if (tbp[NDTPA_IFINDEX])
			ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
1909

1910
		p = lookup_neigh_parms(tbl, net, ifindex);
1911 1912
		if (p == NULL) {
			err = -ENOENT;
1913
			goto errout_tbl_lock;
1914 1915
		}

1916 1917 1918
		for (i = 1; i <= NDTPA_MAX; i++) {
			if (tbp[i] == NULL)
				continue;
1919

1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959
			switch (i) {
			case NDTPA_QUEUE_LEN:
				p->queue_len = nla_get_u32(tbp[i]);
				break;
			case NDTPA_PROXY_QLEN:
				p->proxy_qlen = nla_get_u32(tbp[i]);
				break;
			case NDTPA_APP_PROBES:
				p->app_probes = nla_get_u32(tbp[i]);
				break;
			case NDTPA_UCAST_PROBES:
				p->ucast_probes = nla_get_u32(tbp[i]);
				break;
			case NDTPA_MCAST_PROBES:
				p->mcast_probes = nla_get_u32(tbp[i]);
				break;
			case NDTPA_BASE_REACHABLE_TIME:
				p->base_reachable_time = nla_get_msecs(tbp[i]);
				break;
			case NDTPA_GC_STALETIME:
				p->gc_staletime = nla_get_msecs(tbp[i]);
				break;
			case NDTPA_DELAY_PROBE_TIME:
				p->delay_probe_time = nla_get_msecs(tbp[i]);
				break;
			case NDTPA_RETRANS_TIME:
				p->retrans_time = nla_get_msecs(tbp[i]);
				break;
			case NDTPA_ANYCAST_DELAY:
				p->anycast_delay = nla_get_msecs(tbp[i]);
				break;
			case NDTPA_PROXY_DELAY:
				p->proxy_delay = nla_get_msecs(tbp[i]);
				break;
			case NDTPA_LOCKTIME:
				p->locktime = nla_get_msecs(tbp[i]);
				break;
			}
		}
	}
1960

1961 1962
	if (tb[NDTA_THRESH1])
		tbl->gc_thresh1 = nla_get_u32(tb[NDTA_THRESH1]);
1963

1964 1965
	if (tb[NDTA_THRESH2])
		tbl->gc_thresh2 = nla_get_u32(tb[NDTA_THRESH2]);
1966

1967 1968
	if (tb[NDTA_THRESH3])
		tbl->gc_thresh3 = nla_get_u32(tb[NDTA_THRESH3]);
1969

1970 1971
	if (tb[NDTA_GC_INTERVAL])
		tbl->gc_interval = nla_get_msecs(tb[NDTA_GC_INTERVAL]);
1972 1973 1974

	err = 0;

1975
errout_tbl_lock:
1976
	write_unlock_bh(&tbl->lock);
1977
errout_locked:
1978
	read_unlock(&neigh_tbl_lock);
1979
errout:
1980 1981 1982
	return err;
}

1983
static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
1984
{
1985
	struct net *net = sock_net(skb->sk);
1986 1987 1988
	int family, tidx, nidx = 0;
	int tbl_skip = cb->args[0];
	int neigh_skip = cb->args[1];
1989 1990
	struct neigh_table *tbl;

1991
	family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
1992 1993

	read_lock(&neigh_tbl_lock);
1994
	for (tbl = neigh_tables, tidx = 0; tbl; tbl = tbl->next, tidx++) {
1995 1996
		struct neigh_parms *p;

1997
		if (tidx < tbl_skip || (family && tbl->family != family))
1998 1999
			continue;

2000 2001 2002
		if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).pid,
				       cb->nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
				       NLM_F_MULTI) <= 0)
2003 2004
			break;

2005
		for (nidx = 0, p = tbl->parms.next; p; p = p->next) {
2006
			if (!net_eq(neigh_parms_net(p), net))
2007 2008
				continue;

2009 2010
			if (nidx < neigh_skip)
				goto next;
2011

2012 2013 2014 2015 2016
			if (neightbl_fill_param_info(skb, tbl, p,
						     NETLINK_CB(cb->skb).pid,
						     cb->nlh->nlmsg_seq,
						     RTM_NEWNEIGHTBL,
						     NLM_F_MULTI) <= 0)
2017
				goto out;
2018 2019
		next:
			nidx++;
2020 2021
		}

2022
		neigh_skip = 0;
2023 2024 2025
	}
out:
	read_unlock(&neigh_tbl_lock);
2026 2027
	cb->args[0] = tidx;
	cb->args[1] = nidx;
2028 2029 2030

	return skb->len;
}
L
Linus Torvalds 已提交
2031

2032 2033
static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
			   u32 pid, u32 seq, int type, unsigned int flags)
L
Linus Torvalds 已提交
2034 2035 2036
{
	unsigned long now = jiffies;
	struct nda_cacheinfo ci;
2037 2038 2039 2040 2041
	struct nlmsghdr *nlh;
	struct ndmsg *ndm;

	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
	if (nlh == NULL)
2042
		return -EMSGSIZE;
L
Linus Torvalds 已提交
2043

2044 2045
	ndm = nlmsg_data(nlh);
	ndm->ndm_family	 = neigh->ops->family;
2046 2047
	ndm->ndm_pad1    = 0;
	ndm->ndm_pad2    = 0;
2048 2049 2050
	ndm->ndm_flags	 = neigh->flags;
	ndm->ndm_type	 = neigh->type;
	ndm->ndm_ifindex = neigh->dev->ifindex;
L
Linus Torvalds 已提交
2051

2052 2053 2054 2055 2056 2057 2058 2059 2060 2061
	NLA_PUT(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key);

	read_lock_bh(&neigh->lock);
	ndm->ndm_state	 = neigh->nud_state;
	if ((neigh->nud_state & NUD_VALID) &&
	    nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, neigh->ha) < 0) {
		read_unlock_bh(&neigh->lock);
		goto nla_put_failure;
	}

2062 2063 2064
	ci.ndm_used	 = jiffies_to_clock_t(now - neigh->used);
	ci.ndm_confirmed = jiffies_to_clock_t(now - neigh->confirmed);
	ci.ndm_updated	 = jiffies_to_clock_t(now - neigh->updated);
2065 2066 2067 2068 2069 2070 2071 2072 2073
	ci.ndm_refcnt	 = atomic_read(&neigh->refcnt) - 1;
	read_unlock_bh(&neigh->lock);

	NLA_PUT_U32(skb, NDA_PROBES, atomic_read(&neigh->probes));
	NLA_PUT(skb, NDA_CACHEINFO, sizeof(ci), &ci);

	return nlmsg_end(skb, nlh);

nla_put_failure:
2074 2075
	nlmsg_cancel(skb, nlh);
	return -EMSGSIZE;
L
Linus Torvalds 已提交
2076 2077
}

T
Thomas Graf 已提交
2078 2079 2080 2081 2082
static void neigh_update_notify(struct neighbour *neigh)
{
	call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
	__neigh_notify(neigh, RTM_NEWNEIGH, 0);
}
L
Linus Torvalds 已提交
2083 2084 2085 2086

static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
			    struct netlink_callback *cb)
{
2087
	struct net * net = sock_net(skb->sk);
L
Linus Torvalds 已提交
2088 2089 2090 2091
	struct neighbour *n;
	int rc, h, s_h = cb->args[1];
	int idx, s_idx = idx = cb->args[2];

2092
	read_lock_bh(&tbl->lock);
L
Linus Torvalds 已提交
2093 2094 2095 2096 2097
	for (h = 0; h <= tbl->hash_mask; h++) {
		if (h < s_h)
			continue;
		if (h > s_h)
			s_idx = 0;
2098
		for (n = tbl->hash_buckets[h], idx = 0; n; n = n->next) {
O
Octavian Purdila 已提交
2099
			if (!net_eq(dev_net(n->dev), net))
2100
				continue;
2101 2102
			if (idx < s_idx)
				goto next;
L
Linus Torvalds 已提交
2103 2104
			if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).pid,
					    cb->nlh->nlmsg_seq,
2105 2106
					    RTM_NEWNEIGH,
					    NLM_F_MULTI) <= 0) {
L
Linus Torvalds 已提交
2107 2108 2109 2110
				read_unlock_bh(&tbl->lock);
				rc = -1;
				goto out;
			}
2111 2112
		next:
			idx++;
L
Linus Torvalds 已提交
2113 2114
		}
	}
2115
	read_unlock_bh(&tbl->lock);
L
Linus Torvalds 已提交
2116 2117 2118 2119 2120 2121 2122
	rc = skb->len;
out:
	cb->args[1] = h;
	cb->args[2] = idx;
	return rc;
}

2123
static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
L
Linus Torvalds 已提交
2124 2125 2126 2127 2128
{
	struct neigh_table *tbl;
	int t, family, s_t;

	read_lock(&neigh_tbl_lock);
2129
	family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
L
Linus Torvalds 已提交
2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182
	s_t = cb->args[0];

	for (tbl = neigh_tables, t = 0; tbl; tbl = tbl->next, t++) {
		if (t < s_t || (family && tbl->family != family))
			continue;
		if (t > s_t)
			memset(&cb->args[1], 0, sizeof(cb->args) -
						sizeof(cb->args[0]));
		if (neigh_dump_table(tbl, skb, cb) < 0)
			break;
	}
	read_unlock(&neigh_tbl_lock);

	cb->args[0] = t;
	return skb->len;
}

void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
{
	int chain;

	read_lock_bh(&tbl->lock);
	for (chain = 0; chain <= tbl->hash_mask; chain++) {
		struct neighbour *n;

		for (n = tbl->hash_buckets[chain]; n; n = n->next)
			cb(n, cookie);
	}
	read_unlock_bh(&tbl->lock);
}
EXPORT_SYMBOL(neigh_for_each);

/* The tbl->lock must be held as a writer and BH disabled. */
void __neigh_for_each_release(struct neigh_table *tbl,
			      int (*cb)(struct neighbour *))
{
	int chain;

	for (chain = 0; chain <= tbl->hash_mask; chain++) {
		struct neighbour *n, **np;

		np = &tbl->hash_buckets[chain];
		while ((n = *np) != NULL) {
			int release;

			write_lock(&n->lock);
			release = cb(n);
			if (release) {
				*np = n->next;
				n->dead = 1;
			} else
				np = &n->next;
			write_unlock(&n->lock);
2183 2184
			if (release)
				neigh_cleanup_and_release(n);
L
Linus Torvalds 已提交
2185 2186 2187 2188 2189 2190 2191 2192 2193 2194
		}
	}
}
EXPORT_SYMBOL(__neigh_for_each_release);

#ifdef CONFIG_PROC_FS

static struct neighbour *neigh_get_first(struct seq_file *seq)
{
	struct neigh_seq_state *state = seq->private;
2195
	struct net *net = seq_file_net(seq);
L
Linus Torvalds 已提交
2196 2197 2198 2199 2200 2201 2202 2203 2204
	struct neigh_table *tbl = state->tbl;
	struct neighbour *n = NULL;
	int bucket = state->bucket;

	state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
	for (bucket = 0; bucket <= tbl->hash_mask; bucket++) {
		n = tbl->hash_buckets[bucket];

		while (n) {
2205
			if (!net_eq(dev_net(n->dev), net))
2206
				goto next;
L
Linus Torvalds 已提交
2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235
			if (state->neigh_sub_iter) {
				loff_t fakep = 0;
				void *v;

				v = state->neigh_sub_iter(state, n, &fakep);
				if (!v)
					goto next;
			}
			if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
				break;
			if (n->nud_state & ~NUD_NOARP)
				break;
		next:
			n = n->next;
		}

		if (n)
			break;
	}
	state->bucket = bucket;

	return n;
}

static struct neighbour *neigh_get_next(struct seq_file *seq,
					struct neighbour *n,
					loff_t *pos)
{
	struct neigh_seq_state *state = seq->private;
2236
	struct net *net = seq_file_net(seq);
L
Linus Torvalds 已提交
2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247
	struct neigh_table *tbl = state->tbl;

	if (state->neigh_sub_iter) {
		void *v = state->neigh_sub_iter(state, n, pos);
		if (v)
			return n;
	}
	n = n->next;

	while (1) {
		while (n) {
2248
			if (!net_eq(dev_net(n->dev), net))
2249
				goto next;
L
Linus Torvalds 已提交
2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283
			if (state->neigh_sub_iter) {
				void *v = state->neigh_sub_iter(state, n, pos);
				if (v)
					return n;
				goto next;
			}
			if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
				break;

			if (n->nud_state & ~NUD_NOARP)
				break;
		next:
			n = n->next;
		}

		if (n)
			break;

		if (++state->bucket > tbl->hash_mask)
			break;

		n = tbl->hash_buckets[state->bucket];
	}

	if (n && pos)
		--(*pos);
	return n;
}

static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
{
	struct neighbour *n = neigh_get_first(seq);

	if (n) {
2284
		--(*pos);
L
Linus Torvalds 已提交
2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296
		while (*pos) {
			n = neigh_get_next(seq, n, pos);
			if (!n)
				break;
		}
	}
	return *pos ? NULL : n;
}

static struct pneigh_entry *pneigh_get_first(struct seq_file *seq)
{
	struct neigh_seq_state *state = seq->private;
2297
	struct net *net = seq_file_net(seq);
L
Linus Torvalds 已提交
2298 2299 2300 2301 2302 2303 2304
	struct neigh_table *tbl = state->tbl;
	struct pneigh_entry *pn = NULL;
	int bucket = state->bucket;

	state->flags |= NEIGH_SEQ_IS_PNEIGH;
	for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
		pn = tbl->phash_buckets[bucket];
2305
		while (pn && !net_eq(pneigh_net(pn), net))
2306
			pn = pn->next;
L
Linus Torvalds 已提交
2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319
		if (pn)
			break;
	}
	state->bucket = bucket;

	return pn;
}

static struct pneigh_entry *pneigh_get_next(struct seq_file *seq,
					    struct pneigh_entry *pn,
					    loff_t *pos)
{
	struct neigh_seq_state *state = seq->private;
2320
	struct net *net = seq_file_net(seq);
L
Linus Torvalds 已提交
2321 2322 2323 2324 2325 2326 2327
	struct neigh_table *tbl = state->tbl;

	pn = pn->next;
	while (!pn) {
		if (++state->bucket > PNEIGH_HASHMASK)
			break;
		pn = tbl->phash_buckets[state->bucket];
2328
		while (pn && !net_eq(pneigh_net(pn), net))
2329
			pn = pn->next;
L
Linus Torvalds 已提交
2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344
		if (pn)
			break;
	}

	if (pn && pos)
		--(*pos);

	return pn;
}

static struct pneigh_entry *pneigh_get_idx(struct seq_file *seq, loff_t *pos)
{
	struct pneigh_entry *pn = pneigh_get_first(seq);

	if (pn) {
2345
		--(*pos);
L
Linus Torvalds 已提交
2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358
		while (*pos) {
			pn = pneigh_get_next(seq, pn, pos);
			if (!pn)
				break;
		}
	}
	return *pos ? NULL : pn;
}

static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
{
	struct neigh_seq_state *state = seq->private;
	void *rc;
2359
	loff_t idxpos = *pos;
L
Linus Torvalds 已提交
2360

2361
	rc = neigh_get_idx(seq, &idxpos);
L
Linus Torvalds 已提交
2362
	if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
2363
		rc = pneigh_get_idx(seq, &idxpos);
L
Linus Torvalds 已提交
2364 2365 2366 2367 2368

	return rc;
}

void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
2369
	__acquires(tbl->lock)
L
Linus Torvalds 已提交
2370 2371 2372 2373 2374 2375 2376 2377 2378
{
	struct neigh_seq_state *state = seq->private;

	state->tbl = tbl;
	state->bucket = 0;
	state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);

	read_lock_bh(&tbl->lock);

2379
	return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
L
Linus Torvalds 已提交
2380 2381 2382 2383 2384 2385 2386 2387 2388
}
EXPORT_SYMBOL(neigh_seq_start);

void *neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
	struct neigh_seq_state *state;
	void *rc;

	if (v == SEQ_START_TOKEN) {
2389
		rc = neigh_get_first(seq);
L
Linus Torvalds 已提交
2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410
		goto out;
	}

	state = seq->private;
	if (!(state->flags & NEIGH_SEQ_IS_PNEIGH)) {
		rc = neigh_get_next(seq, v, NULL);
		if (rc)
			goto out;
		if (!(state->flags & NEIGH_SEQ_NEIGH_ONLY))
			rc = pneigh_get_first(seq);
	} else {
		BUG_ON(state->flags & NEIGH_SEQ_NEIGH_ONLY);
		rc = pneigh_get_next(seq, v, NULL);
	}
out:
	++(*pos);
	return rc;
}
EXPORT_SYMBOL(neigh_seq_next);

void neigh_seq_stop(struct seq_file *seq, void *v)
2411
	__releases(tbl->lock)
L
Linus Torvalds 已提交
2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423
{
	struct neigh_seq_state *state = seq->private;
	struct neigh_table *tbl = state->tbl;

	read_unlock_bh(&tbl->lock);
}
EXPORT_SYMBOL(neigh_seq_stop);

/* statistics via seq_file */

static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
{
A
Alexey Dobriyan 已提交
2424
	struct neigh_table *tbl = seq->private;
L
Linus Torvalds 已提交
2425 2426 2427 2428
	int cpu;

	if (*pos == 0)
		return SEQ_START_TOKEN;
2429

2430
	for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
L
Linus Torvalds 已提交
2431 2432 2433 2434 2435 2436 2437 2438 2439 2440
		if (!cpu_possible(cpu))
			continue;
		*pos = cpu+1;
		return per_cpu_ptr(tbl->stats, cpu);
	}
	return NULL;
}

static void *neigh_stat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
A
Alexey Dobriyan 已提交
2441
	struct neigh_table *tbl = seq->private;
L
Linus Torvalds 已提交
2442 2443
	int cpu;

2444
	for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
L
Linus Torvalds 已提交
2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459
		if (!cpu_possible(cpu))
			continue;
		*pos = cpu+1;
		return per_cpu_ptr(tbl->stats, cpu);
	}
	return NULL;
}

static void neigh_stat_seq_stop(struct seq_file *seq, void *v)
{

}

static int neigh_stat_seq_show(struct seq_file *seq, void *v)
{
A
Alexey Dobriyan 已提交
2460
	struct neigh_table *tbl = seq->private;
L
Linus Torvalds 已提交
2461 2462 2463
	struct neigh_statistics *st = v;

	if (v == SEQ_START_TOKEN) {
2464
		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");
L
Linus Torvalds 已提交
2465 2466 2467 2468
		return 0;
	}

	seq_printf(seq, "%08x  %08lx %08lx %08lx  %08lx %08lx  %08lx  "
2469
			"%08lx %08lx  %08lx %08lx %08lx\n",
L
Linus Torvalds 已提交
2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484
		   atomic_read(&tbl->entries),

		   st->allocs,
		   st->destroys,
		   st->hash_grows,

		   st->lookups,
		   st->hits,

		   st->res_failed,

		   st->rcv_probes_mcast,
		   st->rcv_probes_ucast,

		   st->periodic_gc_runs,
2485 2486
		   st->forced_gc_runs,
		   st->unres_discards
L
Linus Torvalds 已提交
2487 2488 2489 2490 2491
		   );

	return 0;
}

2492
static const struct seq_operations neigh_stat_seq_ops = {
L
Linus Torvalds 已提交
2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504
	.start	= neigh_stat_seq_start,
	.next	= neigh_stat_seq_next,
	.stop	= neigh_stat_seq_stop,
	.show	= neigh_stat_seq_show,
};

static int neigh_stat_seq_open(struct inode *inode, struct file *file)
{
	int ret = seq_open(file, &neigh_stat_seq_ops);

	if (!ret) {
		struct seq_file *sf = file->private_data;
A
Alexey Dobriyan 已提交
2505
		sf->private = PDE(inode)->data;
L
Linus Torvalds 已提交
2506 2507 2508 2509
	}
	return ret;
};

2510
static const struct file_operations neigh_stat_seq_fops = {
L
Linus Torvalds 已提交
2511 2512 2513 2514 2515 2516 2517 2518 2519
	.owner	 = THIS_MODULE,
	.open 	 = neigh_stat_seq_open,
	.read	 = seq_read,
	.llseek	 = seq_lseek,
	.release = seq_release,
};

#endif /* CONFIG_PROC_FS */

2520 2521 2522 2523 2524 2525 2526 2527 2528
static inline size_t neigh_nlmsg_size(void)
{
	return NLMSG_ALIGN(sizeof(struct ndmsg))
	       + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
	       + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */
	       + nla_total_size(sizeof(struct nda_cacheinfo))
	       + nla_total_size(4); /* NDA_PROBES */
}

2529
static void __neigh_notify(struct neighbour *n, int type, int flags)
L
Linus Torvalds 已提交
2530
{
2531
	struct net *net = dev_net(n->dev);
2532
	struct sk_buff *skb;
2533
	int err = -ENOBUFS;
L
Linus Torvalds 已提交
2534

2535
	skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
2536
	if (skb == NULL)
2537
		goto errout;
L
Linus Torvalds 已提交
2538

2539
	err = neigh_fill_info(skb, n, 0, 0, type, flags);
2540 2541 2542 2543 2544 2545
	if (err < 0) {
		/* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
		WARN_ON(err == -EMSGSIZE);
		kfree_skb(skb);
		goto errout;
	}
2546 2547
	rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
	return;
2548 2549
errout:
	if (err < 0)
2550
		rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
L
Linus Torvalds 已提交
2551 2552
}

T
Thomas Graf 已提交
2553
#ifdef CONFIG_ARPD
2554
void neigh_app_ns(struct neighbour *n)
L
Linus Torvalds 已提交
2555
{
2556 2557
	__neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST);
}
2558
EXPORT_SYMBOL(neigh_app_ns);
L
Linus Torvalds 已提交
2559 2560 2561 2562
#endif /* CONFIG_ARPD */

#ifdef CONFIG_SYSCTL

2563 2564
#define NEIGH_VARS_MAX 19

L
Linus Torvalds 已提交
2565 2566
static struct neigh_sysctl_table {
	struct ctl_table_header *sysctl_header;
2567
	struct ctl_table neigh_vars[NEIGH_VARS_MAX];
2568
	char *dev_name;
2569
} neigh_sysctl_template __read_mostly = {
L
Linus Torvalds 已提交
2570 2571 2572 2573 2574
	.neigh_vars = {
		{
			.procname	= "mcast_solicit",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2575
			.proc_handler	= proc_dointvec,
L
Linus Torvalds 已提交
2576 2577 2578 2579 2580
		},
		{
			.procname	= "ucast_solicit",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2581
			.proc_handler	= proc_dointvec,
L
Linus Torvalds 已提交
2582 2583 2584 2585 2586
		},
		{
			.procname	= "app_solicit",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2587
			.proc_handler	= proc_dointvec,
L
Linus Torvalds 已提交
2588 2589 2590 2591 2592
		},
		{
			.procname	= "retrans_time",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2593
			.proc_handler	= proc_dointvec_userhz_jiffies,
L
Linus Torvalds 已提交
2594 2595 2596 2597 2598
		},
		{
			.procname	= "base_reachable_time",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2599
			.proc_handler	= proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2600 2601 2602 2603 2604
		},
		{
			.procname	= "delay_first_probe_time",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2605
			.proc_handler	= proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2606 2607 2608 2609 2610
		},
		{
			.procname	= "gc_stale_time",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2611
			.proc_handler	= proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2612 2613 2614 2615 2616
		},
		{
			.procname	= "unres_qlen",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2617
			.proc_handler	= proc_dointvec,
L
Linus Torvalds 已提交
2618 2619 2620 2621 2622
		},
		{
			.procname	= "proxy_qlen",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2623
			.proc_handler	= proc_dointvec,
L
Linus Torvalds 已提交
2624 2625 2626 2627 2628
		},
		{
			.procname	= "anycast_delay",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2629
			.proc_handler	= proc_dointvec_userhz_jiffies,
L
Linus Torvalds 已提交
2630 2631 2632 2633 2634
		},
		{
			.procname	= "proxy_delay",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2635
			.proc_handler	= proc_dointvec_userhz_jiffies,
L
Linus Torvalds 已提交
2636 2637 2638 2639 2640
		},
		{
			.procname	= "locktime",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2641
			.proc_handler	= proc_dointvec_userhz_jiffies,
L
Linus Torvalds 已提交
2642
		},
2643 2644 2645 2646
		{
			.procname	= "retrans_time_ms",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2647
			.proc_handler	= proc_dointvec_ms_jiffies,
2648 2649 2650 2651 2652
		},
		{
			.procname	= "base_reachable_time_ms",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2653
			.proc_handler	= proc_dointvec_ms_jiffies,
2654
		},
L
Linus Torvalds 已提交
2655 2656 2657 2658
		{
			.procname	= "gc_interval",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2659
			.proc_handler	= proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2660 2661 2662 2663 2664
		},
		{
			.procname	= "gc_thresh1",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2665
			.proc_handler	= proc_dointvec,
L
Linus Torvalds 已提交
2666 2667 2668 2669 2670
		},
		{
			.procname	= "gc_thresh2",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2671
			.proc_handler	= proc_dointvec,
L
Linus Torvalds 已提交
2672 2673 2674 2675 2676
		},
		{
			.procname	= "gc_thresh3",
			.maxlen		= sizeof(int),
			.mode		= 0644,
A
Alexey Dobriyan 已提交
2677
			.proc_handler	= proc_dointvec,
L
Linus Torvalds 已提交
2678
		},
2679
		{},
L
Linus Torvalds 已提交
2680 2681 2682 2683
	},
};

int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
2684
			  char *p_name, proc_handler *handler)
L
Linus Torvalds 已提交
2685
{
2686
	struct neigh_sysctl_table *t;
L
Linus Torvalds 已提交
2687
	const char *dev_name_source = NULL;
2688 2689 2690 2691 2692 2693 2694

#define NEIGH_CTL_PATH_ROOT	0
#define NEIGH_CTL_PATH_PROTO	1
#define NEIGH_CTL_PATH_NEIGH	2
#define NEIGH_CTL_PATH_DEV	3

	struct ctl_path neigh_path[] = {
2695 2696 2697 2698
		{ .procname = "net",	 },
		{ .procname = "proto",	 },
		{ .procname = "neigh",	 },
		{ .procname = "default", },
2699 2700
		{ },
	};
L
Linus Torvalds 已提交
2701

2702
	t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL);
L
Linus Torvalds 已提交
2703
	if (!t)
2704 2705
		goto err;

L
Linus Torvalds 已提交
2706 2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717
	t->neigh_vars[0].data  = &p->mcast_probes;
	t->neigh_vars[1].data  = &p->ucast_probes;
	t->neigh_vars[2].data  = &p->app_probes;
	t->neigh_vars[3].data  = &p->retrans_time;
	t->neigh_vars[4].data  = &p->base_reachable_time;
	t->neigh_vars[5].data  = &p->delay_probe_time;
	t->neigh_vars[6].data  = &p->gc_staletime;
	t->neigh_vars[7].data  = &p->queue_len;
	t->neigh_vars[8].data  = &p->proxy_qlen;
	t->neigh_vars[9].data  = &p->anycast_delay;
	t->neigh_vars[10].data = &p->proxy_delay;
	t->neigh_vars[11].data = &p->locktime;
2718 2719
	t->neigh_vars[12].data  = &p->retrans_time;
	t->neigh_vars[13].data  = &p->base_reachable_time;
L
Linus Torvalds 已提交
2720 2721 2722

	if (dev) {
		dev_name_source = dev->name;
2723 2724
		/* Terminate the table early */
		memset(&t->neigh_vars[14], 0, sizeof(t->neigh_vars[14]));
L
Linus Torvalds 已提交
2725
	} else {
2726
		dev_name_source = neigh_path[NEIGH_CTL_PATH_DEV].procname;
2727 2728 2729 2730
		t->neigh_vars[14].data = (int *)(p + 1);
		t->neigh_vars[15].data = (int *)(p + 1) + 1;
		t->neigh_vars[16].data = (int *)(p + 1) + 2;
		t->neigh_vars[17].data = (int *)(p + 1) + 3;
L
Linus Torvalds 已提交
2731 2732 2733
	}


2734
	if (handler) {
L
Linus Torvalds 已提交
2735 2736 2737 2738 2739 2740 2741
		/* RetransTime */
		t->neigh_vars[3].proc_handler = handler;
		t->neigh_vars[3].extra1 = dev;
		/* ReachableTime */
		t->neigh_vars[4].proc_handler = handler;
		t->neigh_vars[4].extra1 = dev;
		/* RetransTime (in milliseconds)*/
2742 2743
		t->neigh_vars[12].proc_handler = handler;
		t->neigh_vars[12].extra1 = dev;
L
Linus Torvalds 已提交
2744
		/* ReachableTime (in milliseconds) */
2745 2746
		t->neigh_vars[13].proc_handler = handler;
		t->neigh_vars[13].extra1 = dev;
L
Linus Torvalds 已提交
2747 2748
	}

2749 2750
	t->dev_name = kstrdup(dev_name_source, GFP_KERNEL);
	if (!t->dev_name)
L
Linus Torvalds 已提交
2751 2752
		goto free;

2753 2754
	neigh_path[NEIGH_CTL_PATH_DEV].procname = t->dev_name;
	neigh_path[NEIGH_CTL_PATH_PROTO].procname = p_name;
L
Linus Torvalds 已提交
2755

2756
	t->sysctl_header =
2757
		register_net_sysctl_table(neigh_parms_net(p), neigh_path, t->neigh_vars);
2758
	if (!t->sysctl_header)
L
Linus Torvalds 已提交
2759
		goto free_procname;
2760

L
Linus Torvalds 已提交
2761 2762 2763
	p->sysctl_table = t;
	return 0;

2764
free_procname:
2765
	kfree(t->dev_name);
2766
free:
L
Linus Torvalds 已提交
2767
	kfree(t);
2768 2769
err:
	return -ENOBUFS;
L
Linus Torvalds 已提交
2770
}
2771
EXPORT_SYMBOL(neigh_sysctl_register);
L
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2772 2773 2774 2775 2776 2777 2778

void neigh_sysctl_unregister(struct neigh_parms *p)
{
	if (p->sysctl_table) {
		struct neigh_sysctl_table *t = p->sysctl_table;
		p->sysctl_table = NULL;
		unregister_sysctl_table(t->sysctl_header);
2779
		kfree(t->dev_name);
L
Linus Torvalds 已提交
2780 2781 2782
		kfree(t);
	}
}
2783
EXPORT_SYMBOL(neigh_sysctl_unregister);
L
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2784 2785 2786

#endif	/* CONFIG_SYSCTL */

2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800
static int __init neigh_init(void)
{
	rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL);
	rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL);
	rtnl_register(PF_UNSPEC, RTM_GETNEIGH, NULL, neigh_dump_info);

	rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info);
	rtnl_register(PF_UNSPEC, RTM_SETNEIGHTBL, neightbl_set, NULL);

	return 0;
}

subsys_initcall(neigh_init);