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linux/net/core/neighbour.c
Gilad Naaman f7f5273863 neighbour: Create netdev->neighbour association 
Create a mapping between a netdev and its neighoburs,
allowing for much cheaper flushes.

Signed-off-by: Gilad Naaman <gnaaman@drivenets.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20241107160444.2913124-7-gnaaman@drivenets.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-09 13:22:57 -08:00

3839 lines
96 KiB
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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Generic address resolution entity
*
* Authors:
* Pedro Roque <roque@di.fc.ul.pt>
* Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
*
* Fixes:
* Vitaly E. Lavrov releasing NULL neighbor in neigh_add.
* Harald Welte Add neighbour cache statistics like rtstat
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/slab.h>
#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>
#include <net/net_namespace.h>
#include <net/neighbour.h>
#include <net/arp.h>
#include <net/dst.h>
#include <net/sock.h>
#include <net/netevent.h>
#include <net/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/random.h>
#include <linux/string.h>
#include <linux/log2.h>
#include <linux/inetdevice.h>
#include <net/addrconf.h>
#include <trace/events/neigh.h>
#define NEIGH_DEBUG 1
#define neigh_dbg(level, fmt, ...) \
do { \
if (level <= NEIGH_DEBUG) \
pr_debug(fmt, ##__VA_ARGS__); \
} while (0)
#define PNEIGH_HASHMASK 0xF
static void neigh_timer_handler(struct timer_list *t);
static void __neigh_notify(struct neighbour *n, int type, int flags,
u32 pid);
static void neigh_update_notify(struct neighbour *neigh, u32 nlmsg_pid);
static int pneigh_ifdown_and_unlock(struct neigh_table *tbl,
struct net_device *dev);
#ifdef CONFIG_PROC_FS
static const struct seq_operations neigh_stat_seq_ops;
#endif
static struct hlist_head *neigh_get_dev_table(struct net_device *dev, int family)
{
int i;
switch (family) {
default:
DEBUG_NET_WARN_ON_ONCE(1);
fallthrough; /* to avoid panic by null-ptr-deref */
case AF_INET:
i = NEIGH_ARP_TABLE;
break;
case AF_INET6:
i = NEIGH_ND_TABLE;
break;
}
return &dev->neighbours[i];
}
/*
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.
*/
static int neigh_blackhole(struct neighbour *neigh, struct sk_buff *skb)
{
kfree_skb(skb);
return -ENETDOWN;
}
static void neigh_cleanup_and_release(struct neighbour *neigh)
{
trace_neigh_cleanup_and_release(neigh, 0);
__neigh_notify(neigh, RTM_DELNEIGH, 0, 0);
call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
neigh_release(neigh);
}
/*
* 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)
{
return base ? get_random_u32_below(base) + (base >> 1) : 0;
}
EXPORT_SYMBOL(neigh_rand_reach_time);
static void neigh_mark_dead(struct neighbour *n)
{
n->dead = 1;
if (!list_empty(&n->gc_list)) {
list_del_init(&n->gc_list);
atomic_dec(&n->tbl->gc_entries);
}
if (!list_empty(&n->managed_list))
list_del_init(&n->managed_list);
}
static void neigh_update_gc_list(struct neighbour *n)
{
bool on_gc_list, exempt_from_gc;
write_lock_bh(&n->tbl->lock);
write_lock(&n->lock);
if (n->dead)
goto out;
/* remove from the gc list if new state is permanent or if neighbor
* is externally learned; otherwise entry should be on the gc list
*/
exempt_from_gc = n->nud_state & NUD_PERMANENT ||
n->flags & NTF_EXT_LEARNED;
on_gc_list = !list_empty(&n->gc_list);
if (exempt_from_gc && on_gc_list) {
list_del_init(&n->gc_list);
atomic_dec(&n->tbl->gc_entries);
} else if (!exempt_from_gc && !on_gc_list) {
/* add entries to the tail; cleaning removes from the front */
list_add_tail(&n->gc_list, &n->tbl->gc_list);
atomic_inc(&n->tbl->gc_entries);
}
out:
write_unlock(&n->lock);
write_unlock_bh(&n->tbl->lock);
}
static void neigh_update_managed_list(struct neighbour *n)
{
bool on_managed_list, add_to_managed;
write_lock_bh(&n->tbl->lock);
write_lock(&n->lock);
if (n->dead)
goto out;
add_to_managed = n->flags & NTF_MANAGED;
on_managed_list = !list_empty(&n->managed_list);
if (!add_to_managed && on_managed_list)
list_del_init(&n->managed_list);
else if (add_to_managed && !on_managed_list)
list_add_tail(&n->managed_list, &n->tbl->managed_list);
out:
write_unlock(&n->lock);
write_unlock_bh(&n->tbl->lock);
}
static void neigh_update_flags(struct neighbour *neigh, u32 flags, int *notify,
bool *gc_update, bool *managed_update)
{
u32 ndm_flags, old_flags = neigh->flags;
if (!(flags & NEIGH_UPDATE_F_ADMIN))
return;
ndm_flags = (flags & NEIGH_UPDATE_F_EXT_LEARNED) ? NTF_EXT_LEARNED : 0;
ndm_flags |= (flags & NEIGH_UPDATE_F_MANAGED) ? NTF_MANAGED : 0;
if ((old_flags ^ ndm_flags) & NTF_EXT_LEARNED) {
if (ndm_flags & NTF_EXT_LEARNED)
neigh->flags |= NTF_EXT_LEARNED;
else
neigh->flags &= ~NTF_EXT_LEARNED;
*notify = 1;
*gc_update = true;
}
if ((old_flags ^ ndm_flags) & NTF_MANAGED) {
if (ndm_flags & NTF_MANAGED)
neigh->flags |= NTF_MANAGED;
else
neigh->flags &= ~NTF_MANAGED;
*notify = 1;
*managed_update = true;
}
}
bool neigh_remove_one(struct neighbour *n)
{
bool retval = false;
write_lock(&n->lock);
if (refcount_read(&n->refcnt) == 1) {
hlist_del_rcu(&n->hash);
hlist_del_rcu(&n->dev_list);
neigh_mark_dead(n);
retval = true;
}
write_unlock(&n->lock);
if (retval)
neigh_cleanup_and_release(n);
return retval;
}
static int neigh_forced_gc(struct neigh_table *tbl)
{
int max_clean = atomic_read(&tbl->gc_entries) -
READ_ONCE(tbl->gc_thresh2);
u64 tmax = ktime_get_ns() + NSEC_PER_MSEC;
unsigned long tref = jiffies - 5 * HZ;
struct neighbour *n, *tmp;
int shrunk = 0;
int loop = 0;
NEIGH_CACHE_STAT_INC(tbl, forced_gc_runs);
write_lock_bh(&tbl->lock);
list_for_each_entry_safe(n, tmp, &tbl->gc_list, gc_list) {
if (refcount_read(&n->refcnt) == 1) {
bool remove = false;
write_lock(&n->lock);
if ((n->nud_state == NUD_FAILED) ||
(n->nud_state == NUD_NOARP) ||
(tbl->is_multicast &&
tbl->is_multicast(n->primary_key)) ||
!time_in_range(n->updated, tref, jiffies))
remove = true;
write_unlock(&n->lock);
if (remove && neigh_remove_one(n))
shrunk++;
if (shrunk >= max_clean)
break;
if (++loop == 16) {
if (ktime_get_ns() > tmax)
goto unlock;
loop = 0;
}
}
}
WRITE_ONCE(tbl->last_flush, jiffies);
unlock:
write_unlock_bh(&tbl->lock);
return shrunk;
}
static void neigh_add_timer(struct neighbour *n, unsigned long when)
{
/* Use safe distance from the jiffies - LONG_MAX point while timer
* is running in DELAY/PROBE state but still show to user space
* large times in the past.
*/
unsigned long mint = jiffies - (LONG_MAX - 86400 * HZ);
neigh_hold(n);
if (!time_in_range(n->confirmed, mint, jiffies))
n->confirmed = mint;
if (time_before(n->used, n->confirmed))
n->used = n->confirmed;
if (unlikely(mod_timer(&n->timer, when))) {
printk("NEIGH: BUG, double timer add, state is %x\n",
n->nud_state);
dump_stack();
}
}
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 struct neigh_parms *neigh_get_dev_parms_rcu(struct net_device *dev,
int family)
{
switch (family) {
case AF_INET:
return __in_dev_arp_parms_get_rcu(dev);
case AF_INET6:
return __in6_dev_nd_parms_get_rcu(dev);
}
return NULL;
}
static void neigh_parms_qlen_dec(struct net_device *dev, int family)
{
struct neigh_parms *p;
rcu_read_lock();
p = neigh_get_dev_parms_rcu(dev, family);
if (p)
p->qlen--;
rcu_read_unlock();
}
static void pneigh_queue_purge(struct sk_buff_head *list, struct net *net,
int family)
{
struct sk_buff_head tmp;
unsigned long flags;
struct sk_buff *skb;
skb_queue_head_init(&tmp);
spin_lock_irqsave(&list->lock, flags);
skb = skb_peek(list);
while (skb != NULL) {
struct sk_buff *skb_next = skb_peek_next(skb, list);
struct net_device *dev = skb->dev;
if (net == NULL || net_eq(dev_net(dev), net)) {
neigh_parms_qlen_dec(dev, family);
__skb_unlink(skb, list);
__skb_queue_tail(&tmp, skb);
}
skb = skb_next;
}
spin_unlock_irqrestore(&list->lock, flags);
while ((skb = __skb_dequeue(&tmp))) {
dev_put(skb->dev);
kfree_skb(skb);
}
}
static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev,
bool skip_perm)
{
struct hlist_head *dev_head;
struct hlist_node *tmp;
struct neighbour *n;
dev_head = neigh_get_dev_table(dev, tbl->family);
hlist_for_each_entry_safe(n, tmp, dev_head, dev_list) {
if (skip_perm && n->nud_state & NUD_PERMANENT)
continue;
hlist_del_rcu(&n->hash);
hlist_del_rcu(&n->dev_list);
write_lock(&n->lock);
neigh_del_timer(n);
neigh_mark_dead(n);
if (refcount_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->arp_queue_len_bytes = 0;
WRITE_ONCE(n->output, neigh_blackhole);
if (n->nud_state & NUD_VALID)
n->nud_state = NUD_NOARP;
else
n->nud_state = NUD_NONE;
neigh_dbg(2, "neigh %p is stray\n", n);
}
write_unlock(&n->lock);
neigh_cleanup_and_release(n);
}
}
void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev)
{
write_lock_bh(&tbl->lock);
neigh_flush_dev(tbl, dev, false);
write_unlock_bh(&tbl->lock);
}
EXPORT_SYMBOL(neigh_changeaddr);
static int __neigh_ifdown(struct neigh_table *tbl, struct net_device *dev,
bool skip_perm)
{
write_lock_bh(&tbl->lock);
neigh_flush_dev(tbl, dev, skip_perm);
pneigh_ifdown_and_unlock(tbl, dev);
pneigh_queue_purge(&tbl->proxy_queue, dev ? dev_net(dev) : NULL,
tbl->family);
if (skb_queue_empty_lockless(&tbl->proxy_queue))
del_timer_sync(&tbl->proxy_timer);
return 0;
}
int neigh_carrier_down(struct neigh_table *tbl, struct net_device *dev)
{
__neigh_ifdown(tbl, dev, true);
return 0;
}
EXPORT_SYMBOL(neigh_carrier_down);
int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev)
{
__neigh_ifdown(tbl, dev, false);
return 0;
}
EXPORT_SYMBOL(neigh_ifdown);
static struct neighbour *neigh_alloc(struct neigh_table *tbl,
struct net_device *dev,
u32 flags, bool exempt_from_gc)
{
struct neighbour *n = NULL;
unsigned long now = jiffies;
int entries, gc_thresh3;
if (exempt_from_gc)
goto do_alloc;
entries = atomic_inc_return(&tbl->gc_entries) - 1;
gc_thresh3 = READ_ONCE(tbl->gc_thresh3);
if (entries >= gc_thresh3 ||
(entries >= READ_ONCE(tbl->gc_thresh2) &&
time_after(now, READ_ONCE(tbl->last_flush) + 5 * HZ))) {
if (!neigh_forced_gc(tbl) && entries >= gc_thresh3) {
net_info_ratelimited("%s: neighbor table overflow!\n",
tbl->id);
NEIGH_CACHE_STAT_INC(tbl, table_fulls);
goto out_entries;
}
}
do_alloc:
n = kzalloc(tbl->entry_size + dev->neigh_priv_len, GFP_ATOMIC);
if (!n)
goto out_entries;
__skb_queue_head_init(&n->arp_queue);
rwlock_init(&n->lock);
seqlock_init(&n->ha_lock);
n->updated = n->used = now;
n->nud_state = NUD_NONE;
n->output = neigh_blackhole;
n->flags = flags;
seqlock_init(&n->hh.hh_lock);
n->parms = neigh_parms_clone(&tbl->parms);
timer_setup(&n->timer, neigh_timer_handler, 0);
NEIGH_CACHE_STAT_INC(tbl, allocs);
n->tbl = tbl;
refcount_set(&n->refcnt, 1);
n->dead = 1;
INIT_LIST_HEAD(&n->gc_list);
INIT_LIST_HEAD(&n->managed_list);
atomic_inc(&tbl->entries);
out:
return n;
out_entries:
if (!exempt_from_gc)
atomic_dec(&tbl->gc_entries);
goto out;
}
static void neigh_get_hash_rnd(u32 *x)
{
*x = get_random_u32() | 1;
}
static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)
{
size_t size = (1 << shift) * sizeof(struct hlist_head);
struct hlist_head *hash_heads;
struct neigh_hash_table *ret;
int i;
ret = kmalloc(sizeof(*ret), GFP_ATOMIC);
if (!ret)
return NULL;
hash_heads = kvzalloc(size, GFP_ATOMIC);
if (!hash_heads) {
kfree(ret);
return NULL;
}
ret->hash_heads = hash_heads;
ret->hash_shift = shift;
for (i = 0; i < NEIGH_NUM_HASH_RND; i++)
neigh_get_hash_rnd(&ret->hash_rnd[i]);
return ret;
}
static void neigh_hash_free_rcu(struct rcu_head *head)
{
struct neigh_hash_table *nht = container_of(head,
struct neigh_hash_table,
rcu);
kvfree(nht->hash_heads);
kfree(nht);
}
static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl,
unsigned long new_shift)
{
unsigned int i, hash;
struct neigh_hash_table *new_nht, *old_nht;
NEIGH_CACHE_STAT_INC(tbl, hash_grows);
old_nht = rcu_dereference_protected(tbl->nht,
lockdep_is_held(&tbl->lock));
new_nht = neigh_hash_alloc(new_shift);
if (!new_nht)
return old_nht;
for (i = 0; i < (1 << old_nht->hash_shift); i++) {
struct hlist_node *tmp;
struct neighbour *n;
neigh_for_each_in_bucket_safe(n, tmp, &old_nht->hash_heads[i]) {
hash = tbl->hash(n->primary_key, n->dev,
new_nht->hash_rnd);
hash >>= (32 - new_nht->hash_shift);
hlist_del_rcu(&n->hash);
hlist_add_head_rcu(&n->hash, &new_nht->hash_heads[hash]);
}
}
rcu_assign_pointer(tbl->nht, new_nht);
call_rcu(&old_nht->rcu, neigh_hash_free_rcu);
return new_nht;
}
struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
struct net_device *dev)
{
struct neighbour *n;
NEIGH_CACHE_STAT_INC(tbl, lookups);
rcu_read_lock();
n = __neigh_lookup_noref(tbl, pkey, dev);
if (n) {
if (!refcount_inc_not_zero(&n->refcnt))
n = NULL;
NEIGH_CACHE_STAT_INC(tbl, hits);
}
rcu_read_unlock();
return n;
}
EXPORT_SYMBOL(neigh_lookup);
static struct neighbour *
___neigh_create(struct neigh_table *tbl, const void *pkey,
struct net_device *dev, u32 flags,
bool exempt_from_gc, bool want_ref)
{
u32 hash_val, key_len = tbl->key_len;
struct neighbour *n1, *rc, *n;
struct neigh_hash_table *nht;
int error;
n = neigh_alloc(tbl, dev, flags, exempt_from_gc);
trace_neigh_create(tbl, dev, pkey, n, exempt_from_gc);
if (!n) {
rc = ERR_PTR(-ENOBUFS);
goto out;
}
memcpy(n->primary_key, pkey, key_len);
n->dev = dev;
netdev_hold(dev, &n->dev_tracker, GFP_ATOMIC);
/* Protocol specific setup. */
if (tbl->constructor && (error = tbl->constructor(n)) < 0) {
rc = ERR_PTR(error);
goto out_neigh_release;
}
if (dev->netdev_ops->ndo_neigh_construct) {
error = dev->netdev_ops->ndo_neigh_construct(dev, n);
if (error < 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 - (NEIGH_VAR(n->parms, BASE_REACHABLE_TIME) << 1);
write_lock_bh(&tbl->lock);
nht = rcu_dereference_protected(tbl->nht,
lockdep_is_held(&tbl->lock));
if (atomic_read(&tbl->entries) > (1 << nht->hash_shift))
nht = neigh_hash_grow(tbl, nht->hash_shift + 1);
hash_val = tbl->hash(n->primary_key, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
if (n->parms->dead) {
rc = ERR_PTR(-EINVAL);
goto out_tbl_unlock;
}
neigh_for_each_in_bucket(n1, &nht->hash_heads[hash_val]) {
if (dev == n1->dev && !memcmp(n1->primary_key, n->primary_key, key_len)) {
if (want_ref)
neigh_hold(n1);
rc = n1;
goto out_tbl_unlock;
}
}
n->dead = 0;
if (!exempt_from_gc)
list_add_tail(&n->gc_list, &n->tbl->gc_list);
if (n->flags & NTF_MANAGED)
list_add_tail(&n->managed_list, &n->tbl->managed_list);
if (want_ref)
neigh_hold(n);
hlist_add_head_rcu(&n->hash, &nht->hash_heads[hash_val]);
hlist_add_head_rcu(&n->dev_list,
neigh_get_dev_table(dev, tbl->family));
write_unlock_bh(&tbl->lock);
neigh_dbg(2, "neigh %p is created\n", n);
rc = n;
out:
return rc;
out_tbl_unlock:
write_unlock_bh(&tbl->lock);
out_neigh_release:
if (!exempt_from_gc)
atomic_dec(&tbl->gc_entries);
neigh_release(n);
goto out;
}
struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
struct net_device *dev, bool want_ref)
{
bool exempt_from_gc = !!(dev->flags & IFF_LOOPBACK);
return ___neigh_create(tbl, pkey, dev, 0, exempt_from_gc, want_ref);
}
EXPORT_SYMBOL(__neigh_create);
static u32 pneigh_hash(const void *pkey, unsigned int key_len)
{
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;
return hash_val;
}
static struct pneigh_entry *__pneigh_lookup_1(struct pneigh_entry *n,
struct net *net,
const void *pkey,
unsigned int key_len,
struct net_device *dev)
{
while (n) {
if (!memcmp(n->key, pkey, key_len) &&
net_eq(pneigh_net(n), net) &&
(n->dev == dev || !n->dev))
return n;
n = n->next;
}
return NULL;
}
struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
struct net *net, const void *pkey, struct net_device *dev)
{
unsigned 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);
}
EXPORT_SYMBOL_GPL(__pneigh_lookup);
struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl,
struct net *net, const void *pkey,
struct net_device *dev, int creat)
{
struct pneigh_entry *n;
unsigned int key_len = tbl->key_len;
u32 hash_val = pneigh_hash(pkey, key_len);
read_lock_bh(&tbl->lock);
n = __pneigh_lookup_1(tbl->phash_buckets[hash_val],
net, pkey, key_len, dev);
read_unlock_bh(&tbl->lock);
if (n || !creat)
goto out;
ASSERT_RTNL();
n = kzalloc(sizeof(*n) + key_len, GFP_KERNEL);
if (!n)
goto out;
write_pnet(&n->net, net);
memcpy(n->key, pkey, key_len);
n->dev = dev;
netdev_hold(dev, &n->dev_tracker, GFP_KERNEL);
if (tbl->pconstructor && tbl->pconstructor(n)) {
netdev_put(dev, &n->dev_tracker);
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;
}
EXPORT_SYMBOL(pneigh_lookup);
int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey,
struct net_device *dev)
{
struct pneigh_entry *n, **np;
unsigned int key_len = tbl->key_len;
u32 hash_val = pneigh_hash(pkey, key_len);
write_lock_bh(&tbl->lock);
for (np = &tbl->phash_buckets[hash_val]; (n = *np) != NULL;
np = &n->next) {
if (!memcmp(n->key, pkey, key_len) && n->dev == dev &&
net_eq(pneigh_net(n), net)) {
*np = n->next;
write_unlock_bh(&tbl->lock);
if (tbl->pdestructor)
tbl->pdestructor(n);
netdev_put(n->dev, &n->dev_tracker);
kfree(n);
return 0;
}
}
write_unlock_bh(&tbl->lock);
return -ENOENT;
}
static int pneigh_ifdown_and_unlock(struct neigh_table *tbl,
struct net_device *dev)
{
struct pneigh_entry *n, **np, *freelist = NULL;
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;
n->next = freelist;
freelist = n;
continue;
}
np = &n->next;
}
}
write_unlock_bh(&tbl->lock);
while ((n = freelist)) {
freelist = n->next;
n->next = NULL;
if (tbl->pdestructor)
tbl->pdestructor(n);
netdev_put(n->dev, &n->dev_tracker);
kfree(n);
}
return -ENOENT;
}
static void neigh_parms_destroy(struct neigh_parms *parms);
static inline void neigh_parms_put(struct neigh_parms *parms)
{
if (refcount_dec_and_test(&parms->refcnt))
neigh_parms_destroy(parms);
}
/*
* neighbour must already be out of the table;
*
*/
void neigh_destroy(struct neighbour *neigh)
{
struct net_device *dev = neigh->dev;
NEIGH_CACHE_STAT_INC(neigh->tbl, destroys);
if (!neigh->dead) {
pr_warn("Destroying alive neighbour %p\n", neigh);
dump_stack();
return;
}
if (neigh_del_timer(neigh))
pr_warn("Impossible event\n");
write_lock_bh(&neigh->lock);
__skb_queue_purge(&neigh->arp_queue);
write_unlock_bh(&neigh->lock);
neigh->arp_queue_len_bytes = 0;
if (dev->netdev_ops->ndo_neigh_destroy)
dev->netdev_ops->ndo_neigh_destroy(dev, neigh);
netdev_put(dev, &neigh->dev_tracker);
neigh_parms_put(neigh->parms);
neigh_dbg(2, "neigh %p is destroyed\n", neigh);
atomic_dec(&neigh->tbl->entries);
kfree_rcu(neigh, rcu);
}
EXPORT_SYMBOL(neigh_destroy);
/* Neighbour state is suspicious;
disable fast path.
Called with write_locked neigh.
*/
static void neigh_suspect(struct neighbour *neigh)
{
neigh_dbg(2, "neigh %p is suspected\n", neigh);
WRITE_ONCE(neigh->output, neigh->ops->output);
}
/* Neighbour state is OK;
enable fast path.
Called with write_locked neigh.
*/
static void neigh_connect(struct neighbour *neigh)
{
neigh_dbg(2, "neigh %p is connected\n", neigh);
WRITE_ONCE(neigh->output, neigh->ops->connected_output);
}
static void neigh_periodic_work(struct work_struct *work)
{
struct neigh_table *tbl = container_of(work, struct neigh_table, gc_work.work);
struct neigh_hash_table *nht;
struct hlist_node *tmp;
struct neighbour *n;
unsigned int i;
NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs);
write_lock_bh(&tbl->lock);
nht = rcu_dereference_protected(tbl->nht,
lockdep_is_held(&tbl->lock));
/*
* periodically recompute ReachableTime from random function
*/
if (time_after(jiffies, tbl->last_rand + 300 * HZ)) {
struct neigh_parms *p;
WRITE_ONCE(tbl->last_rand, jiffies);
list_for_each_entry(p, &tbl->parms_list, list)
p->reachable_time =
neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
}
if (atomic_read(&tbl->entries) < READ_ONCE(tbl->gc_thresh1))
goto out;
for (i = 0 ; i < (1 << nht->hash_shift); i++) {
neigh_for_each_in_bucket_safe(n, tmp, &nht->hash_heads[i]) {
unsigned int state;
write_lock(&n->lock);
state = n->nud_state;
if ((state & (NUD_PERMANENT | NUD_IN_TIMER)) ||
(n->flags & NTF_EXT_LEARNED)) {
write_unlock(&n->lock);
continue;
}
if (time_before(n->used, n->confirmed) &&
time_is_before_eq_jiffies(n->confirmed))
n->used = n->confirmed;
if (refcount_read(&n->refcnt) == 1 &&
(state == NUD_FAILED ||
!time_in_range_open(jiffies, n->used,
n->used + NEIGH_VAR(n->parms, GC_STALETIME)))) {
hlist_del_rcu(&n->hash);
hlist_del_rcu(&n->dev_list);
neigh_mark_dead(n);
write_unlock(&n->lock);
neigh_cleanup_and_release(n);
continue;
}
write_unlock(&n->lock);
}
/*
* 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);
nht = rcu_dereference_protected(tbl->nht,
lockdep_is_held(&tbl->lock));
}
out:
/* 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.
*/
queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME) >> 1);
write_unlock_bh(&tbl->lock);
}
static __inline__ int neigh_max_probes(struct neighbour *n)
{
struct neigh_parms *p = n->parms;
return NEIGH_VAR(p, UCAST_PROBES) + NEIGH_VAR(p, APP_PROBES) +
(n->nud_state & NUD_PROBE ? NEIGH_VAR(p, MCAST_REPROBES) :
NEIGH_VAR(p, MCAST_PROBES));
}
static void neigh_invalidate(struct neighbour *neigh)
__releases(neigh->lock)
__acquires(neigh->lock)
{
struct sk_buff *skb;
NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed);
neigh_dbg(2, "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);
neigh->arp_queue_len_bytes = 0;
}
static void neigh_probe(struct neighbour *neigh)
__releases(neigh->lock)
{
struct sk_buff *skb = skb_peek_tail(&neigh->arp_queue);
/* keep skb alive even if arp_queue overflows */
if (skb)
skb = skb_clone(skb, GFP_ATOMIC);
write_unlock(&neigh->lock);
if (neigh->ops->solicit)
neigh->ops->solicit(neigh, skb);
atomic_inc(&neigh->probes);
consume_skb(skb);
}
/* Called when a timer expires for a neighbour entry. */
static void neigh_timer_handler(struct timer_list *t)
{
unsigned long now, next;
struct neighbour *neigh = from_timer(neigh, t, timer);
unsigned int state;
int notify = 0;
write_lock(&neigh->lock);
state = neigh->nud_state;
now = jiffies;
next = now + HZ;
if (!(state & NUD_IN_TIMER))
goto out;
if (state & NUD_REACHABLE) {
if (time_before_eq(now,
neigh->confirmed + neigh->parms->reachable_time)) {
neigh_dbg(2, "neigh %p is still alive\n", neigh);
next = neigh->confirmed + neigh->parms->reachable_time;
} else if (time_before_eq(now,
neigh->used +
NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
neigh_dbg(2, "neigh %p is delayed\n", neigh);
WRITE_ONCE(neigh->nud_state, NUD_DELAY);
neigh->updated = jiffies;
neigh_suspect(neigh);
next = now + NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME);
} else {
neigh_dbg(2, "neigh %p is suspected\n", neigh);
WRITE_ONCE(neigh->nud_state, NUD_STALE);
neigh->updated = jiffies;
neigh_suspect(neigh);
notify = 1;
}
} else if (state & NUD_DELAY) {
if (time_before_eq(now,
neigh->confirmed +
NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME))) {
neigh_dbg(2, "neigh %p is now reachable\n", neigh);
WRITE_ONCE(neigh->nud_state, NUD_REACHABLE);
neigh->updated = jiffies;
neigh_connect(neigh);
notify = 1;
next = neigh->confirmed + neigh->parms->reachable_time;
} else {
neigh_dbg(2, "neigh %p is probed\n", neigh);
WRITE_ONCE(neigh->nud_state, NUD_PROBE);
neigh->updated = jiffies;
atomic_set(&neigh->probes, 0);
notify = 1;
next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
HZ/100);
}
} else {
/* NUD_PROBE|NUD_INCOMPLETE */
next = now + max(NEIGH_VAR(neigh->parms, RETRANS_TIME), HZ/100);
}
if ((neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) &&
atomic_read(&neigh->probes) >= neigh_max_probes(neigh)) {
WRITE_ONCE(neigh->nud_state, NUD_FAILED);
notify = 1;
neigh_invalidate(neigh);
goto out;
}
if (neigh->nud_state & NUD_IN_TIMER) {
if (time_before(next, jiffies + HZ/100))
next = jiffies + HZ/100;
if (!mod_timer(&neigh->timer, next))
neigh_hold(neigh);
}
if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) {
neigh_probe(neigh);
} else {
out:
write_unlock(&neigh->lock);
}
if (notify)
neigh_update_notify(neigh, 0);
trace_neigh_timer_handler(neigh, 0);
neigh_release(neigh);
}
int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb,
const bool immediate_ok)
{
int rc;
bool immediate_probe = false;
write_lock_bh(&neigh->lock);
rc = 0;
if (neigh->nud_state & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE))
goto out_unlock_bh;
if (neigh->dead)
goto out_dead;
if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) {
if (NEIGH_VAR(neigh->parms, MCAST_PROBES) +
NEIGH_VAR(neigh->parms, APP_PROBES)) {
unsigned long next, now = jiffies;
atomic_set(&neigh->probes,
NEIGH_VAR(neigh->parms, UCAST_PROBES));
neigh_del_timer(neigh);
WRITE_ONCE(neigh->nud_state, NUD_INCOMPLETE);
neigh->updated = now;
if (!immediate_ok) {
next = now + 1;
} else {
immediate_probe = true;
next = now + max(NEIGH_VAR(neigh->parms,
RETRANS_TIME),
HZ / 100);
}
neigh_add_timer(neigh, next);
} else {
WRITE_ONCE(neigh->nud_state, NUD_FAILED);
neigh->updated = jiffies;
write_unlock_bh(&neigh->lock);
kfree_skb_reason(skb, SKB_DROP_REASON_NEIGH_FAILED);
return 1;
}
} else if (neigh->nud_state & NUD_STALE) {
neigh_dbg(2, "neigh %p is delayed\n", neigh);
neigh_del_timer(neigh);
WRITE_ONCE(neigh->nud_state, NUD_DELAY);
neigh->updated = jiffies;
neigh_add_timer(neigh, jiffies +
NEIGH_VAR(neigh->parms, DELAY_PROBE_TIME));
}
if (neigh->nud_state == NUD_INCOMPLETE) {
if (skb) {
while (neigh->arp_queue_len_bytes + skb->truesize >
NEIGH_VAR(neigh->parms, QUEUE_LEN_BYTES)) {
struct sk_buff *buff;
buff = __skb_dequeue(&neigh->arp_queue);
if (!buff)
break;
neigh->arp_queue_len_bytes -= buff->truesize;
kfree_skb_reason(buff, SKB_DROP_REASON_NEIGH_QUEUEFULL);
NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
}
skb_dst_force(skb);
__skb_queue_tail(&neigh->arp_queue, skb);
neigh->arp_queue_len_bytes += skb->truesize;
}
rc = 1;
}
out_unlock_bh:
if (immediate_probe)
neigh_probe(neigh);
else
write_unlock(&neigh->lock);
local_bh_enable();
trace_neigh_event_send_done(neigh, rc);
return rc;
out_dead:
if (neigh->nud_state & NUD_STALE)
goto out_unlock_bh;
write_unlock_bh(&neigh->lock);
kfree_skb_reason(skb, SKB_DROP_REASON_NEIGH_DEAD);
trace_neigh_event_send_dead(neigh, 1);
return 1;
}
EXPORT_SYMBOL(__neigh_event_send);
static void neigh_update_hhs(struct neighbour *neigh)
{
struct hh_cache *hh;
void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
= NULL;
if (neigh->dev->header_ops)
update = neigh->dev->header_ops->cache_update;
if (update) {
hh = &neigh->hh;
if (READ_ONCE(hh->hh_len)) {
write_seqlock_bh(&hh->hh_lock);
update(hh, neigh->dev, neigh->ha);
write_sequnlock_bh(&hh->hh_lock);
}
}
}
/* 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"
lladdr instead of overriding it
if it is different.
NEIGH_UPDATE_F_ADMIN means that the change is administrative.
NEIGH_UPDATE_F_USE means that the entry is user triggered.
NEIGH_UPDATE_F_MANAGED means that the entry will be auto-refreshed.
NEIGH_UPDATE_F_OVERRIDE_ISROUTER allows to override existing
NTF_ROUTER flag.
NEIGH_UPDATE_F_ISROUTER indicates if the neighbour is known as
a router.
Caller MUST hold reference count on the entry.
*/
static int __neigh_update(struct neighbour *neigh, const u8 *lladdr,
u8 new, u32 flags, u32 nlmsg_pid,
struct netlink_ext_ack *extack)
{
bool gc_update = false, managed_update = false;
int update_isrouter = 0;
struct net_device *dev;
int err, notify = 0;
u8 old;
trace_neigh_update(neigh, lladdr, new, flags, nlmsg_pid);
write_lock_bh(&neigh->lock);
dev = neigh->dev;
old = neigh->nud_state;
err = -EPERM;
if (neigh->dead) {
NL_SET_ERR_MSG(extack, "Neighbor entry is now dead");
new = old;
goto out;
}
if (!(flags & NEIGH_UPDATE_F_ADMIN) &&
(old & (NUD_NOARP | NUD_PERMANENT)))
goto out;
neigh_update_flags(neigh, flags, &notify, &gc_update, &managed_update);
if (flags & (NEIGH_UPDATE_F_USE | NEIGH_UPDATE_F_MANAGED)) {
new = old & ~NUD_PERMANENT;
WRITE_ONCE(neigh->nud_state, new);
err = 0;
goto out;
}
if (!(new & NUD_VALID)) {
neigh_del_timer(neigh);
if (old & NUD_CONNECTED)
neigh_suspect(neigh);
WRITE_ONCE(neigh->nud_state, new);
err = 0;
notify = old & NUD_VALID;
if ((old & (NUD_INCOMPLETE | NUD_PROBE)) &&
(new & NUD_FAILED)) {
neigh_invalidate(neigh);
notify = 1;
}
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
*/
if ((old & NUD_VALID) &&
!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)) {
NL_SET_ERR_MSG(extack, "No link layer address given");
goto out;
}
lladdr = neigh->ha;
}
/* Update confirmed timestamp for neighbour entry after we
* received ARP packet even if it doesn't change IP to MAC binding.
*/
if (new & NUD_CONNECTED)
neigh->confirmed = 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_ADMIN))
new = old;
}
}
/* Update timestamp only once we know we will make a change to the
* neighbour entry. Otherwise we risk to move the locktime window with
* noop updates and ignore relevant ARP updates.
*/
if (new != old || lladdr != neigh->ha)
neigh->updated = jiffies;
if (new != old) {
neigh_del_timer(neigh);
if (new & NUD_PROBE)
atomic_set(&neigh->probes, 0);
if (new & NUD_IN_TIMER)
neigh_add_timer(neigh, (jiffies +
((new & NUD_REACHABLE) ?
neigh->parms->reachable_time :
0)));
WRITE_ONCE(neigh->nud_state, new);
notify = 1;
}
if (lladdr != neigh->ha) {
write_seqlock(&neigh->ha_lock);
memcpy(&neigh->ha, lladdr, dev->addr_len);
write_sequnlock(&neigh->ha_lock);
neigh_update_hhs(neigh);
if (!(new & NUD_CONNECTED))
neigh->confirmed = jiffies -
(NEIGH_VAR(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 dst_entry *dst = skb_dst(skb);
struct neighbour *n2, *n1 = neigh;
write_unlock_bh(&neigh->lock);
rcu_read_lock();
/* Why not just use 'neigh' as-is? The problem is that
* things such as shaper, eql, and sch_teql can end up
* using alternative, different, neigh objects to output
* the packet in the output path. So what we need to do
* here is re-lookup the top-level neigh in the path so
* we can reinject the packet there.
*/
n2 = NULL;
if (dst && dst->obsolete != DST_OBSOLETE_DEAD) {
n2 = dst_neigh_lookup_skb(dst, skb);
if (n2)
n1 = n2;
}
READ_ONCE(n1->output)(n1, skb);
if (n2)
neigh_release(n2);
rcu_read_unlock();
write_lock_bh(&neigh->lock);
}
__skb_queue_purge(&neigh->arp_queue);
neigh->arp_queue_len_bytes = 0;
}
out:
if (update_isrouter)
neigh_update_is_router(neigh, flags, &notify);
write_unlock_bh(&neigh->lock);
if (((new ^ old) & NUD_PERMANENT) || gc_update)
neigh_update_gc_list(neigh);
if (managed_update)
neigh_update_managed_list(neigh);
if (notify)
neigh_update_notify(neigh, nlmsg_pid);
trace_neigh_update_done(neigh, err);
return err;
}
int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
u32 flags, u32 nlmsg_pid)
{
return __neigh_update(neigh, lladdr, new, flags, nlmsg_pid, NULL);
}
EXPORT_SYMBOL(neigh_update);
/* Update the neigh to listen temporarily for probe responses, even if it is
* in a NUD_FAILED state. The caller has to hold neigh->lock for writing.
*/
void __neigh_set_probe_once(struct neighbour *neigh)
{
if (neigh->dead)
return;
neigh->updated = jiffies;
if (!(neigh->nud_state & NUD_FAILED))
return;
WRITE_ONCE(neigh->nud_state, NUD_INCOMPLETE);
atomic_set(&neigh->probes, neigh_max_probes(neigh));
neigh_add_timer(neigh,
jiffies + max(NEIGH_VAR(neigh->parms, RETRANS_TIME),
HZ/100));
}
EXPORT_SYMBOL(__neigh_set_probe_once);
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)
neigh_update(neigh, lladdr, NUD_STALE,
NEIGH_UPDATE_F_OVERRIDE, 0);
return neigh;
}
EXPORT_SYMBOL(neigh_event_ns);
/* called with read_lock_bh(&n->lock); */
static void neigh_hh_init(struct neighbour *n)
{
struct net_device *dev = n->dev;
__be16 prot = n->tbl->protocol;
struct hh_cache *hh = &n->hh;
write_lock_bh(&n->lock);
/* Only one thread can come in here and initialize the
* hh_cache entry.
*/
if (!hh->hh_len)
dev->header_ops->cache(n, hh, prot);
write_unlock_bh(&n->lock);
}
/* Slow and careful. */
int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb)
{
int rc = 0;
if (!neigh_event_send(neigh, skb)) {
int err;
struct net_device *dev = neigh->dev;
unsigned int seq;
if (dev->header_ops->cache && !READ_ONCE(neigh->hh.hh_len))
neigh_hh_init(neigh);
do {
__skb_pull(skb, skb_network_offset(skb));
seq = read_seqbegin(&neigh->ha_lock);
err = dev_hard_header(skb, dev, ntohs(skb->protocol),
neigh->ha, NULL, skb->len);
} while (read_seqretry(&neigh->ha_lock, seq));
if (err >= 0)
rc = dev_queue_xmit(skb);
else
goto out_kfree_skb;
}
out:
return rc;
out_kfree_skb:
rc = -EINVAL;
kfree_skb(skb);
goto out;
}
EXPORT_SYMBOL(neigh_resolve_output);
/* As fast as possible without hh cache */
int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb)
{
struct net_device *dev = neigh->dev;
unsigned int seq;
int err;
do {
__skb_pull(skb, skb_network_offset(skb));
seq = read_seqbegin(&neigh->ha_lock);
err = dev_hard_header(skb, dev, ntohs(skb->protocol),
neigh->ha, NULL, skb->len);
} while (read_seqretry(&neigh->ha_lock, seq));
if (err >= 0)
err = dev_queue_xmit(skb);
else {
err = -EINVAL;
kfree_skb(skb);
}
return err;
}
EXPORT_SYMBOL(neigh_connected_output);
int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb)
{
return dev_queue_xmit(skb);
}
EXPORT_SYMBOL(neigh_direct_output);
static void neigh_managed_work(struct work_struct *work)
{
struct neigh_table *tbl = container_of(work, struct neigh_table,
managed_work.work);
struct neighbour *neigh;
write_lock_bh(&tbl->lock);
list_for_each_entry(neigh, &tbl->managed_list, managed_list)
neigh_event_send_probe(neigh, NULL, false);
queue_delayed_work(system_power_efficient_wq, &tbl->managed_work,
NEIGH_VAR(&tbl->parms, INTERVAL_PROBE_TIME_MS));
write_unlock_bh(&tbl->lock);
}
static void neigh_proxy_process(struct timer_list *t)
{
struct neigh_table *tbl = from_timer(tbl, t, proxy_timer);
long sched_next = 0;
unsigned long now = jiffies;
struct sk_buff *skb, *n;
spin_lock(&tbl->proxy_queue.lock);
skb_queue_walk_safe(&tbl->proxy_queue, skb, n) {
long tdif = NEIGH_CB(skb)->sched_next - now;
if (tdif <= 0) {
struct net_device *dev = skb->dev;
neigh_parms_qlen_dec(dev, tbl->family);
__skb_unlink(skb, &tbl->proxy_queue);
if (tbl->proxy_redo && netif_running(dev)) {
rcu_read_lock();
tbl->proxy_redo(skb);
rcu_read_unlock();
} else {
kfree_skb(skb);
}
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);
}
static unsigned long neigh_proxy_delay(struct neigh_parms *p)
{
/* If proxy_delay is zero, do not call get_random_u32_below()
* as it is undefined behavior.
*/
unsigned long proxy_delay = NEIGH_VAR(p, PROXY_DELAY);
return proxy_delay ?
jiffies + get_random_u32_below(proxy_delay) : jiffies;
}
void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
struct sk_buff *skb)
{
unsigned long sched_next = neigh_proxy_delay(p);
if (p->qlen > NEIGH_VAR(p, PROXY_QLEN)) {
kfree_skb(skb);
return;
}
NEIGH_CB(skb)->sched_next = sched_next;
NEIGH_CB(skb)->flags |= LOCALLY_ENQUEUED;
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;
}
skb_dst_drop(skb);
dev_hold(skb->dev);
__skb_queue_tail(&tbl->proxy_queue, skb);
p->qlen++;
mod_timer(&tbl->proxy_timer, sched_next);
spin_unlock(&tbl->proxy_queue.lock);
}
EXPORT_SYMBOL(pneigh_enqueue);
static inline struct neigh_parms *lookup_neigh_parms(struct neigh_table *tbl,
struct net *net, int ifindex)
{
struct neigh_parms *p;
list_for_each_entry(p, &tbl->parms_list, list) {
if ((p->dev && p->dev->ifindex == ifindex && net_eq(neigh_parms_net(p), net)) ||
(!p->dev && !ifindex && net_eq(net, &init_net)))
return p;
}
return NULL;
}
struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
struct neigh_table *tbl)
{
struct neigh_parms *p;
struct net *net = dev_net(dev);
const struct net_device_ops *ops = dev->netdev_ops;
p = kmemdup(&tbl->parms, sizeof(*p), GFP_KERNEL);
if (p) {
p->tbl = tbl;
refcount_set(&p->refcnt, 1);
p->reachable_time =
neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
p->qlen = 0;
netdev_hold(dev, &p->dev_tracker, GFP_KERNEL);
p->dev = dev;
write_pnet(&p->net, net);
p->sysctl_table = NULL;
if (ops->ndo_neigh_setup && ops->ndo_neigh_setup(dev, p)) {
netdev_put(dev, &p->dev_tracker);
kfree(p);
return NULL;
}
write_lock_bh(&tbl->lock);
list_add(&p->list, &tbl->parms.list);
write_unlock_bh(&tbl->lock);
neigh_parms_data_state_cleanall(p);
}
return p;
}
EXPORT_SYMBOL(neigh_parms_alloc);
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)
{
if (!parms || parms == &tbl->parms)
return;
write_lock_bh(&tbl->lock);
list_del(&parms->list);
parms->dead = 1;
write_unlock_bh(&tbl->lock);
netdev_put(parms->dev, &parms->dev_tracker);
call_rcu(&parms->rcu_head, neigh_rcu_free_parms);
}
EXPORT_SYMBOL(neigh_parms_release);
static void neigh_parms_destroy(struct neigh_parms *parms)
{
kfree(parms);
}
static struct lock_class_key neigh_table_proxy_queue_class;
static struct neigh_table __rcu *neigh_tables[NEIGH_NR_TABLES] __read_mostly;
void neigh_table_init(int index, struct neigh_table *tbl)
{
unsigned long now = jiffies;
unsigned long phsize;
INIT_LIST_HEAD(&tbl->parms_list);
INIT_LIST_HEAD(&tbl->gc_list);
INIT_LIST_HEAD(&tbl->managed_list);
list_add(&tbl->parms.list, &tbl->parms_list);
write_pnet(&tbl->parms.net, &init_net);
refcount_set(&tbl->parms.refcnt, 1);
tbl->parms.reachable_time =
neigh_rand_reach_time(NEIGH_VAR(&tbl->parms, BASE_REACHABLE_TIME));
tbl->parms.qlen = 0;
tbl->stats = alloc_percpu(struct neigh_statistics);
if (!tbl->stats)
panic("cannot create neighbour cache statistics");
#ifdef CONFIG_PROC_FS
if (!proc_create_seq_data(tbl->id, 0, init_net.proc_net_stat,
&neigh_stat_seq_ops, tbl))
panic("cannot create neighbour proc dir entry");
#endif
RCU_INIT_POINTER(tbl->nht, neigh_hash_alloc(3));
phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *);
tbl->phash_buckets = kzalloc(phsize, GFP_KERNEL);
if (!tbl->nht || !tbl->phash_buckets)
panic("cannot allocate neighbour cache hashes");
if (!tbl->entry_size)
tbl->entry_size = ALIGN(offsetof(struct neighbour, primary_key) +
tbl->key_len, NEIGH_PRIV_ALIGN);
else
WARN_ON(tbl->entry_size % NEIGH_PRIV_ALIGN);
rwlock_init(&tbl->lock);
INIT_DEFERRABLE_WORK(&tbl->gc_work, neigh_periodic_work);
queue_delayed_work(system_power_efficient_wq, &tbl->gc_work,
tbl->parms.reachable_time);
INIT_DEFERRABLE_WORK(&tbl->managed_work, neigh_managed_work);
queue_delayed_work(system_power_efficient_wq, &tbl->managed_work, 0);
timer_setup(&tbl->proxy_timer, neigh_proxy_process, 0);
skb_queue_head_init_class(&tbl->proxy_queue,
&neigh_table_proxy_queue_class);
tbl->last_flush = now;
tbl->last_rand = now + tbl->parms.reachable_time * 20;
rcu_assign_pointer(neigh_tables[index], tbl);
}
EXPORT_SYMBOL(neigh_table_init);
/*
* Only called from ndisc_cleanup(), which means this is dead code
* because we no longer can unload IPv6 module.
*/
int neigh_table_clear(int index, struct neigh_table *tbl)
{
RCU_INIT_POINTER(neigh_tables[index], NULL);
synchronize_rcu();
/* It is not clean... Fix it to unload IPv6 module safely */
cancel_delayed_work_sync(&tbl->managed_work);
cancel_delayed_work_sync(&tbl->gc_work);
del_timer_sync(&tbl->proxy_timer);
pneigh_queue_purge(&tbl->proxy_queue, NULL, tbl->family);
neigh_ifdown(tbl, NULL);
if (atomic_read(&tbl->entries))
pr_crit("neighbour leakage\n");
call_rcu(&rcu_dereference_protected(tbl->nht, 1)->rcu,
neigh_hash_free_rcu);
tbl->nht = NULL;
kfree(tbl->phash_buckets);
tbl->phash_buckets = NULL;
remove_proc_entry(tbl->id, init_net.proc_net_stat);
free_percpu(tbl->stats);
tbl->stats = NULL;
return 0;
}
EXPORT_SYMBOL(neigh_table_clear);
static struct neigh_table *neigh_find_table(int family)
{
struct neigh_table *tbl = NULL;
switch (family) {
case AF_INET:
tbl = rcu_dereference_rtnl(neigh_tables[NEIGH_ARP_TABLE]);
break;
case AF_INET6:
tbl = rcu_dereference_rtnl(neigh_tables[NEIGH_ND_TABLE]);
break;
}
return tbl;
}
const struct nla_policy nda_policy[NDA_MAX+1] = {
[NDA_UNSPEC] = { .strict_start_type = NDA_NH_ID },
[NDA_DST] = { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
[NDA_LLADDR] = { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
[NDA_CACHEINFO] = { .len = sizeof(struct nda_cacheinfo) },
[NDA_PROBES] = { .type = NLA_U32 },
[NDA_VLAN] = { .type = NLA_U16 },
[NDA_PORT] = { .type = NLA_U16 },
[NDA_VNI] = { .type = NLA_U32 },
[NDA_IFINDEX] = { .type = NLA_U32 },
[NDA_MASTER] = { .type = NLA_U32 },
[NDA_PROTOCOL] = { .type = NLA_U8 },
[NDA_NH_ID] = { .type = NLA_U32 },
[NDA_FLAGS_EXT] = NLA_POLICY_MASK(NLA_U32, NTF_EXT_MASK),
[NDA_FDB_EXT_ATTRS] = { .type = NLA_NESTED },
};
static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh,
struct netlink_ext_ack *extack)
{
struct net *net = sock_net(skb->sk);
struct ndmsg *ndm;
struct nlattr *dst_attr;
struct neigh_table *tbl;
struct neighbour *neigh;
struct net_device *dev = NULL;
int err = -EINVAL;
ASSERT_RTNL();
if (nlmsg_len(nlh) < sizeof(*ndm))
goto out;
dst_attr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_DST);
if (!dst_attr) {
NL_SET_ERR_MSG(extack, "Network address not specified");
goto out;
}
ndm = nlmsg_data(nlh);
if (ndm->ndm_ifindex) {
dev = __dev_get_by_index(net, ndm->ndm_ifindex);
if (dev == NULL) {
err = -ENODEV;
goto out;
}
}
tbl = neigh_find_table(ndm->ndm_family);
if (tbl == NULL)
return -EAFNOSUPPORT;
if (nla_len(dst_attr) < (int)tbl->key_len) {
NL_SET_ERR_MSG(extack, "Invalid network address");
goto out;
}
if (ndm->ndm_flags & NTF_PROXY) {
err = pneigh_delete(tbl, net, nla_data(dst_attr), dev);
goto out;
}
if (dev == NULL)
goto out;
neigh = neigh_lookup(tbl, nla_data(dst_attr), dev);
if (neigh == NULL) {
err = -ENOENT;
goto out;
}
err = __neigh_update(neigh, NULL, NUD_FAILED,
NEIGH_UPDATE_F_OVERRIDE | NEIGH_UPDATE_F_ADMIN,
NETLINK_CB(skb).portid, extack);
write_lock_bh(&tbl->lock);
neigh_release(neigh);
neigh_remove_one(neigh);
write_unlock_bh(&tbl->lock);
out:
return err;
}
static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh,
struct netlink_ext_ack *extack)
{
int flags = NEIGH_UPDATE_F_ADMIN | NEIGH_UPDATE_F_OVERRIDE |
NEIGH_UPDATE_F_OVERRIDE_ISROUTER;
struct net *net = sock_net(skb->sk);
struct ndmsg *ndm;
struct nlattr *tb[NDA_MAX+1];
struct neigh_table *tbl;
struct net_device *dev = NULL;
struct neighbour *neigh;
void *dst, *lladdr;
u8 protocol = 0;
u32 ndm_flags;
int err;
ASSERT_RTNL();
err = nlmsg_parse_deprecated(nlh, sizeof(*ndm), tb, NDA_MAX,
nda_policy, extack);
if (err < 0)
goto out;
err = -EINVAL;
if (!tb[NDA_DST]) {
NL_SET_ERR_MSG(extack, "Network address not specified");
goto out;
}
ndm = nlmsg_data(nlh);
ndm_flags = ndm->ndm_flags;
if (tb[NDA_FLAGS_EXT]) {
u32 ext = nla_get_u32(tb[NDA_FLAGS_EXT]);
BUILD_BUG_ON(sizeof(neigh->flags) * BITS_PER_BYTE <
(sizeof(ndm->ndm_flags) * BITS_PER_BYTE +
hweight32(NTF_EXT_MASK)));
ndm_flags |= (ext << NTF_EXT_SHIFT);
}
if (ndm->ndm_ifindex) {
dev = __dev_get_by_index(net, ndm->ndm_ifindex);
if (dev == NULL) {
err = -ENODEV;
goto out;
}
if (tb[NDA_LLADDR] && nla_len(tb[NDA_LLADDR]) < dev->addr_len) {
NL_SET_ERR_MSG(extack, "Invalid link address");
goto out;
}
}
tbl = neigh_find_table(ndm->ndm_family);
if (tbl == NULL)
return -EAFNOSUPPORT;
if (nla_len(tb[NDA_DST]) < (int)tbl->key_len) {
NL_SET_ERR_MSG(extack, "Invalid network address");
goto out;
}
dst = nla_data(tb[NDA_DST]);
lladdr = tb[NDA_LLADDR] ? nla_data(tb[NDA_LLADDR]) : NULL;
if (tb[NDA_PROTOCOL])
protocol = nla_get_u8(tb[NDA_PROTOCOL]);
if (ndm_flags & NTF_PROXY) {
struct pneigh_entry *pn;
if (ndm_flags & NTF_MANAGED) {
NL_SET_ERR_MSG(extack, "Invalid NTF_* flag combination");
goto out;
}
err = -ENOBUFS;
pn = pneigh_lookup(tbl, net, dst, dev, 1);
if (pn) {
pn->flags = ndm_flags;
if (protocol)
pn->protocol = protocol;
err = 0;
}
goto out;
}
if (!dev) {
NL_SET_ERR_MSG(extack, "Device not specified");
goto out;
}
if (tbl->allow_add && !tbl->allow_add(dev, extack)) {
err = -EINVAL;
goto out;
}
neigh = neigh_lookup(tbl, dst, dev);
if (neigh == NULL) {
bool ndm_permanent = ndm->ndm_state & NUD_PERMANENT;
bool exempt_from_gc = ndm_permanent ||
ndm_flags & NTF_EXT_LEARNED;
if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
err = -ENOENT;
goto out;
}
if (ndm_permanent && (ndm_flags & NTF_MANAGED)) {
NL_SET_ERR_MSG(extack, "Invalid NTF_* flag for permanent entry");
err = -EINVAL;
goto out;
}
neigh = ___neigh_create(tbl, dst, dev,
ndm_flags &
(NTF_EXT_LEARNED | NTF_MANAGED),
exempt_from_gc, true);
if (IS_ERR(neigh)) {
err = PTR_ERR(neigh);
goto out;
}
} else {
if (nlh->nlmsg_flags & NLM_F_EXCL) {
err = -EEXIST;
neigh_release(neigh);
goto out;
}
if (!(nlh->nlmsg_flags & NLM_F_REPLACE))
flags &= ~(NEIGH_UPDATE_F_OVERRIDE |
NEIGH_UPDATE_F_OVERRIDE_ISROUTER);
}
if (protocol)
neigh->protocol = protocol;
if (ndm_flags & NTF_EXT_LEARNED)
flags |= NEIGH_UPDATE_F_EXT_LEARNED;
if (ndm_flags & NTF_ROUTER)
flags |= NEIGH_UPDATE_F_ISROUTER;
if (ndm_flags & NTF_MANAGED)
flags |= NEIGH_UPDATE_F_MANAGED;
if (ndm_flags & NTF_USE)
flags |= NEIGH_UPDATE_F_USE;
err = __neigh_update(neigh, lladdr, ndm->ndm_state, flags,
NETLINK_CB(skb).portid, extack);
if (!err && ndm_flags & (NTF_USE | NTF_MANAGED)) {
neigh_event_send(neigh, NULL);
err = 0;
}
neigh_release(neigh);
out:
return err;
}
static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms)
{
struct nlattr *nest;
nest = nla_nest_start_noflag(skb, NDTA_PARMS);
if (nest == NULL)
return -ENOBUFS;
if ((parms->dev &&
nla_put_u32(skb, NDTPA_IFINDEX, parms->dev->ifindex)) ||
nla_put_u32(skb, NDTPA_REFCNT, refcount_read(&parms->refcnt)) ||
nla_put_u32(skb, NDTPA_QUEUE_LENBYTES,
NEIGH_VAR(parms, QUEUE_LEN_BYTES)) ||
/* approximative value for deprecated QUEUE_LEN (in packets) */
nla_put_u32(skb, NDTPA_QUEUE_LEN,
NEIGH_VAR(parms, QUEUE_LEN_BYTES) / SKB_TRUESIZE(ETH_FRAME_LEN)) ||
nla_put_u32(skb, NDTPA_PROXY_QLEN, NEIGH_VAR(parms, PROXY_QLEN)) ||
nla_put_u32(skb, NDTPA_APP_PROBES, NEIGH_VAR(parms, APP_PROBES)) ||
nla_put_u32(skb, NDTPA_UCAST_PROBES,
NEIGH_VAR(parms, UCAST_PROBES)) ||
nla_put_u32(skb, NDTPA_MCAST_PROBES,
NEIGH_VAR(parms, MCAST_PROBES)) ||
nla_put_u32(skb, NDTPA_MCAST_REPROBES,
NEIGH_VAR(parms, MCAST_REPROBES)) ||
nla_put_msecs(skb, NDTPA_REACHABLE_TIME, parms->reachable_time,
NDTPA_PAD) ||
nla_put_msecs(skb, NDTPA_BASE_REACHABLE_TIME,
NEIGH_VAR(parms, BASE_REACHABLE_TIME), NDTPA_PAD) ||
nla_put_msecs(skb, NDTPA_GC_STALETIME,
NEIGH_VAR(parms, GC_STALETIME), NDTPA_PAD) ||
nla_put_msecs(skb, NDTPA_DELAY_PROBE_TIME,
NEIGH_VAR(parms, DELAY_PROBE_TIME), NDTPA_PAD) ||
nla_put_msecs(skb, NDTPA_RETRANS_TIME,
NEIGH_VAR(parms, RETRANS_TIME), NDTPA_PAD) ||
nla_put_msecs(skb, NDTPA_ANYCAST_DELAY,
NEIGH_VAR(parms, ANYCAST_DELAY), NDTPA_PAD) ||
nla_put_msecs(skb, NDTPA_PROXY_DELAY,
NEIGH_VAR(parms, PROXY_DELAY), NDTPA_PAD) ||
nla_put_msecs(skb, NDTPA_LOCKTIME,
NEIGH_VAR(parms, LOCKTIME), NDTPA_PAD) ||
nla_put_msecs(skb, NDTPA_INTERVAL_PROBE_TIME_MS,
NEIGH_VAR(parms, INTERVAL_PROBE_TIME_MS), NDTPA_PAD))
goto nla_put_failure;
return nla_nest_end(skb, nest);
nla_put_failure:
nla_nest_cancel(skb, nest);
return -EMSGSIZE;
}
static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
u32 pid, u32 seq, int type, int flags)
{
struct nlmsghdr *nlh;
struct ndtmsg *ndtmsg;
nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
if (nlh == NULL)
return -EMSGSIZE;
ndtmsg = nlmsg_data(nlh);
read_lock_bh(&tbl->lock);
ndtmsg->ndtm_family = tbl->family;
ndtmsg->ndtm_pad1 = 0;
ndtmsg->ndtm_pad2 = 0;
if (nla_put_string(skb, NDTA_NAME, tbl->id) ||
nla_put_msecs(skb, NDTA_GC_INTERVAL, READ_ONCE(tbl->gc_interval),
NDTA_PAD) ||
nla_put_u32(skb, NDTA_THRESH1, READ_ONCE(tbl->gc_thresh1)) ||
nla_put_u32(skb, NDTA_THRESH2, READ_ONCE(tbl->gc_thresh2)) ||
nla_put_u32(skb, NDTA_THRESH3, READ_ONCE(tbl->gc_thresh3)))
goto nla_put_failure;
{
unsigned long now = jiffies;
long flush_delta = now - READ_ONCE(tbl->last_flush);
long rand_delta = now - READ_ONCE(tbl->last_rand);
struct neigh_hash_table *nht;
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_proxy_qlen = READ_ONCE(tbl->proxy_queue.qlen),
};
rcu_read_lock();
nht = rcu_dereference(tbl->nht);
ndc.ndtc_hash_rnd = nht->hash_rnd[0];
ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
rcu_read_unlock();
if (nla_put(skb, NDTA_CONFIG, sizeof(ndc), &ndc))
goto nla_put_failure;
}
{
int cpu;
struct ndt_stats ndst;
memset(&ndst, 0, sizeof(ndst));
for_each_possible_cpu(cpu) {
struct neigh_statistics *st;
st = per_cpu_ptr(tbl->stats, cpu);
ndst.ndts_allocs += READ_ONCE(st->allocs);
ndst.ndts_destroys += READ_ONCE(st->destroys);
ndst.ndts_hash_grows += READ_ONCE(st->hash_grows);
ndst.ndts_res_failed += READ_ONCE(st->res_failed);
ndst.ndts_lookups += READ_ONCE(st->lookups);
ndst.ndts_hits += READ_ONCE(st->hits);
ndst.ndts_rcv_probes_mcast += READ_ONCE(st->rcv_probes_mcast);
ndst.ndts_rcv_probes_ucast += READ_ONCE(st->rcv_probes_ucast);
ndst.ndts_periodic_gc_runs += READ_ONCE(st->periodic_gc_runs);
ndst.ndts_forced_gc_runs += READ_ONCE(st->forced_gc_runs);
ndst.ndts_table_fulls += READ_ONCE(st->table_fulls);
}
if (nla_put_64bit(skb, NDTA_STATS, sizeof(ndst), &ndst,
NDTA_PAD))
goto nla_put_failure;
}
BUG_ON(tbl->parms.dev);
if (neightbl_fill_parms(skb, &tbl->parms) < 0)
goto nla_put_failure;
read_unlock_bh(&tbl->lock);
nlmsg_end(skb, nlh);
return 0;
nla_put_failure:
read_unlock_bh(&tbl->lock);
nlmsg_cancel(skb, nlh);
return -EMSGSIZE;
}
static int neightbl_fill_param_info(struct sk_buff *skb,
struct neigh_table *tbl,
struct neigh_parms *parms,
u32 pid, u32 seq, int type,
unsigned int flags)
{
struct ndtmsg *ndtmsg;
struct nlmsghdr *nlh;
nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndtmsg), flags);
if (nlh == NULL)
return -EMSGSIZE;
ndtmsg = nlmsg_data(nlh);
read_lock_bh(&tbl->lock);
ndtmsg->ndtm_family = tbl->family;
ndtmsg->ndtm_pad1 = 0;
ndtmsg->ndtm_pad2 = 0;
if (nla_put_string(skb, NDTA_NAME, tbl->id) < 0 ||
neightbl_fill_parms(skb, parms) < 0)
goto errout;
read_unlock_bh(&tbl->lock);
nlmsg_end(skb, nlh);
return 0;
errout:
read_unlock_bh(&tbl->lock);
nlmsg_cancel(skb, nlh);
return -EMSGSIZE;
}
static const struct nla_policy nl_neightbl_policy[NDTA_MAX+1] = {
[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 },
};
static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
[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_MCAST_REPROBES] = { .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 },
[NDTPA_INTERVAL_PROBE_TIME_MS] = { .type = NLA_U64, .min = 1 },
};
static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh,
struct netlink_ext_ack *extack)
{
struct net *net = sock_net(skb->sk);
struct neigh_table *tbl;
struct ndtmsg *ndtmsg;
struct nlattr *tb[NDTA_MAX+1];
bool found = false;
int err, tidx;
err = nlmsg_parse_deprecated(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
nl_neightbl_policy, extack);
if (err < 0)
goto errout;
if (tb[NDTA_NAME] == NULL) {
err = -EINVAL;
goto errout;
}
ndtmsg = nlmsg_data(nlh);
for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
tbl = rcu_dereference_rtnl(neigh_tables[tidx]);
if (!tbl)
continue;
if (ndtmsg->ndtm_family && tbl->family != ndtmsg->ndtm_family)
continue;
if (nla_strcmp(tb[NDTA_NAME], tbl->id) == 0) {
found = true;
break;
}
}
if (!found)
return -ENOENT;
/*
* 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);
if (tb[NDTA_PARMS]) {
struct nlattr *tbp[NDTPA_MAX+1];
struct neigh_parms *p;
int i, ifindex = 0;
err = nla_parse_nested_deprecated(tbp, NDTPA_MAX,
tb[NDTA_PARMS],
nl_ntbl_parm_policy, extack);
if (err < 0)
goto errout_tbl_lock;
if (tbp[NDTPA_IFINDEX])
ifindex = nla_get_u32(tbp[NDTPA_IFINDEX]);
p = lookup_neigh_parms(tbl, net, ifindex);
if (p == NULL) {
err = -ENOENT;
goto errout_tbl_lock;
}
for (i = 1; i <= NDTPA_MAX; i++) {
if (tbp[i] == NULL)
continue;
switch (i) {
case NDTPA_QUEUE_LEN:
NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
nla_get_u32(tbp[i]) *
SKB_TRUESIZE(ETH_FRAME_LEN));
break;
case NDTPA_QUEUE_LENBYTES:
NEIGH_VAR_SET(p, QUEUE_LEN_BYTES,
nla_get_u32(tbp[i]));
break;
case NDTPA_PROXY_QLEN:
NEIGH_VAR_SET(p, PROXY_QLEN,
nla_get_u32(tbp[i]));
break;
case NDTPA_APP_PROBES:
NEIGH_VAR_SET(p, APP_PROBES,
nla_get_u32(tbp[i]));
break;
case NDTPA_UCAST_PROBES:
NEIGH_VAR_SET(p, UCAST_PROBES,
nla_get_u32(tbp[i]));
break;
case NDTPA_MCAST_PROBES:
NEIGH_VAR_SET(p, MCAST_PROBES,
nla_get_u32(tbp[i]));
break;
case NDTPA_MCAST_REPROBES:
NEIGH_VAR_SET(p, MCAST_REPROBES,
nla_get_u32(tbp[i]));
break;
case NDTPA_BASE_REACHABLE_TIME:
NEIGH_VAR_SET(p, BASE_REACHABLE_TIME,
nla_get_msecs(tbp[i]));
/* update reachable_time as well, otherwise, the change will
* only be effective after the next time neigh_periodic_work
* decides to recompute it (can be multiple minutes)
*/
p->reachable_time =
neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
break;
case NDTPA_GC_STALETIME:
NEIGH_VAR_SET(p, GC_STALETIME,
nla_get_msecs(tbp[i]));
break;
case NDTPA_DELAY_PROBE_TIME:
NEIGH_VAR_SET(p, DELAY_PROBE_TIME,
nla_get_msecs(tbp[i]));
call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
break;
case NDTPA_INTERVAL_PROBE_TIME_MS:
NEIGH_VAR_SET(p, INTERVAL_PROBE_TIME_MS,
nla_get_msecs(tbp[i]));
break;
case NDTPA_RETRANS_TIME:
NEIGH_VAR_SET(p, RETRANS_TIME,
nla_get_msecs(tbp[i]));
break;
case NDTPA_ANYCAST_DELAY:
NEIGH_VAR_SET(p, ANYCAST_DELAY,
nla_get_msecs(tbp[i]));
break;
case NDTPA_PROXY_DELAY:
NEIGH_VAR_SET(p, PROXY_DELAY,
nla_get_msecs(tbp[i]));
break;
case NDTPA_LOCKTIME:
NEIGH_VAR_SET(p, LOCKTIME,
nla_get_msecs(tbp[i]));
break;
}
}
}
err = -ENOENT;
if ((tb[NDTA_THRESH1] || tb[NDTA_THRESH2] ||
tb[NDTA_THRESH3] || tb[NDTA_GC_INTERVAL]) &&
!net_eq(net, &init_net))
goto errout_tbl_lock;
if (tb[NDTA_THRESH1])
WRITE_ONCE(tbl->gc_thresh1, nla_get_u32(tb[NDTA_THRESH1]));
if (tb[NDTA_THRESH2])
WRITE_ONCE(tbl->gc_thresh2, nla_get_u32(tb[NDTA_THRESH2]));
if (tb[NDTA_THRESH3])
WRITE_ONCE(tbl->gc_thresh3, nla_get_u32(tb[NDTA_THRESH3]));
if (tb[NDTA_GC_INTERVAL])
WRITE_ONCE(tbl->gc_interval, nla_get_msecs(tb[NDTA_GC_INTERVAL]));
err = 0;
errout_tbl_lock:
write_unlock_bh(&tbl->lock);
errout:
return err;
}
static int neightbl_valid_dump_info(const struct nlmsghdr *nlh,
struct netlink_ext_ack *extack)
{
struct ndtmsg *ndtm;
if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndtm))) {
NL_SET_ERR_MSG(extack, "Invalid header for neighbor table dump request");
return -EINVAL;
}
ndtm = nlmsg_data(nlh);
if (ndtm->ndtm_pad1 || ndtm->ndtm_pad2) {
NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor table dump request");
return -EINVAL;
}
if (nlmsg_attrlen(nlh, sizeof(*ndtm))) {
NL_SET_ERR_MSG(extack, "Invalid data after header in neighbor table dump request");
return -EINVAL;
}
return 0;
}
static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
{
const struct nlmsghdr *nlh = cb->nlh;
struct net *net = sock_net(skb->sk);
int family, tidx, nidx = 0;
int tbl_skip = cb->args[0];
int neigh_skip = cb->args[1];
struct neigh_table *tbl;
if (cb->strict_check) {
int err = neightbl_valid_dump_info(nlh, cb->extack);
if (err < 0)
return err;
}
family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family;
for (tidx = 0; tidx < NEIGH_NR_TABLES; tidx++) {
struct neigh_parms *p;
tbl = rcu_dereference_rtnl(neigh_tables[tidx]);
if (!tbl)
continue;
if (tidx < tbl_skip || (family && tbl->family != family))
continue;
if (neightbl_fill_info(skb, tbl, NETLINK_CB(cb->skb).portid,
nlh->nlmsg_seq, RTM_NEWNEIGHTBL,
NLM_F_MULTI) < 0)
break;
nidx = 0;
p = list_next_entry(&tbl->parms, list);
list_for_each_entry_from(p, &tbl->parms_list, list) {
if (!net_eq(neigh_parms_net(p), net))
continue;
if (nidx < neigh_skip)
goto next;
if (neightbl_fill_param_info(skb, tbl, p,
NETLINK_CB(cb->skb).portid,
nlh->nlmsg_seq,
RTM_NEWNEIGHTBL,
NLM_F_MULTI) < 0)
goto out;
next:
nidx++;
}
neigh_skip = 0;
}
out:
cb->args[0] = tidx;
cb->args[1] = nidx;
return skb->len;
}
static int neigh_fill_info(struct sk_buff *skb, struct neighbour *neigh,
u32 pid, u32 seq, int type, unsigned int flags)
{
u32 neigh_flags, neigh_flags_ext;
unsigned long now = jiffies;
struct nda_cacheinfo ci;
struct nlmsghdr *nlh;
struct ndmsg *ndm;
nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
if (nlh == NULL)
return -EMSGSIZE;
neigh_flags_ext = neigh->flags >> NTF_EXT_SHIFT;
neigh_flags = neigh->flags & NTF_OLD_MASK;
ndm = nlmsg_data(nlh);
ndm->ndm_family = neigh->ops->family;
ndm->ndm_pad1 = 0;
ndm->ndm_pad2 = 0;
ndm->ndm_flags = neigh_flags;
ndm->ndm_type = neigh->type;
ndm->ndm_ifindex = neigh->dev->ifindex;
if (nla_put(skb, NDA_DST, neigh->tbl->key_len, neigh->primary_key))
goto nla_put_failure;
read_lock_bh(&neigh->lock);
ndm->ndm_state = neigh->nud_state;
if (neigh->nud_state & NUD_VALID) {
char haddr[MAX_ADDR_LEN];
neigh_ha_snapshot(haddr, neigh, neigh->dev);
if (nla_put(skb, NDA_LLADDR, neigh->dev->addr_len, haddr) < 0) {
read_unlock_bh(&neigh->lock);
goto nla_put_failure;
}
}
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);
ci.ndm_refcnt = refcount_read(&neigh->refcnt) - 1;
read_unlock_bh(&neigh->lock);
if (nla_put_u32(skb, NDA_PROBES, atomic_read(&neigh->probes)) ||
nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
goto nla_put_failure;
if (neigh->protocol && nla_put_u8(skb, NDA_PROTOCOL, neigh->protocol))
goto nla_put_failure;
if (neigh_flags_ext && nla_put_u32(skb, NDA_FLAGS_EXT, neigh_flags_ext))
goto nla_put_failure;
nlmsg_end(skb, nlh);
return 0;
nla_put_failure:
nlmsg_cancel(skb, nlh);
return -EMSGSIZE;
}
static int pneigh_fill_info(struct sk_buff *skb, struct pneigh_entry *pn,
u32 pid, u32 seq, int type, unsigned int flags,
struct neigh_table *tbl)
{
u32 neigh_flags, neigh_flags_ext;
struct nlmsghdr *nlh;
struct ndmsg *ndm;
nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
if (nlh == NULL)
return -EMSGSIZE;
neigh_flags_ext = pn->flags >> NTF_EXT_SHIFT;
neigh_flags = pn->flags & NTF_OLD_MASK;
ndm = nlmsg_data(nlh);
ndm->ndm_family = tbl->family;
ndm->ndm_pad1 = 0;
ndm->ndm_pad2 = 0;
ndm->ndm_flags = neigh_flags | NTF_PROXY;
ndm->ndm_type = RTN_UNICAST;
ndm->ndm_ifindex = pn->dev ? pn->dev->ifindex : 0;
ndm->ndm_state = NUD_NONE;
if (nla_put(skb, NDA_DST, tbl->key_len, pn->key))
goto nla_put_failure;
if (pn->protocol && nla_put_u8(skb, NDA_PROTOCOL, pn->protocol))
goto nla_put_failure;
if (neigh_flags_ext && nla_put_u32(skb, NDA_FLAGS_EXT, neigh_flags_ext))
goto nla_put_failure;
nlmsg_end(skb, nlh);
return 0;
nla_put_failure:
nlmsg_cancel(skb, nlh);
return -EMSGSIZE;
}
static void neigh_update_notify(struct neighbour *neigh, u32 nlmsg_pid)
{
call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, neigh);
__neigh_notify(neigh, RTM_NEWNEIGH, 0, nlmsg_pid);
}
static bool neigh_master_filtered(struct net_device *dev, int master_idx)
{
struct net_device *master;
if (!master_idx)
return false;
master = dev ? netdev_master_upper_dev_get_rcu(dev) : NULL;
/* 0 is already used to denote NDA_MASTER wasn't passed, therefore need another
* invalid value for ifindex to denote "no master".
*/
if (master_idx == -1)
return !!master;
if (!master || master->ifindex != master_idx)
return true;
return false;
}
static bool neigh_ifindex_filtered(struct net_device *dev, int filter_idx)
{
if (filter_idx && (!dev || dev->ifindex != filter_idx))
return true;
return false;
}
struct neigh_dump_filter {
int master_idx;
int dev_idx;
};
static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
struct netlink_callback *cb,
struct neigh_dump_filter *filter)
{
struct net *net = sock_net(skb->sk);
struct neighbour *n;
int err = 0, h, s_h = cb->args[1];
int idx, s_idx = idx = cb->args[2];
struct neigh_hash_table *nht;
unsigned int flags = NLM_F_MULTI;
if (filter->dev_idx || filter->master_idx)
flags |= NLM_F_DUMP_FILTERED;
nht = rcu_dereference(tbl->nht);
for (h = s_h; h < (1 << nht->hash_shift); h++) {
if (h > s_h)
s_idx = 0;
idx = 0;
neigh_for_each_in_bucket_rcu(n, &nht->hash_heads[h]) {
if (idx < s_idx || !net_eq(dev_net(n->dev), net))
goto next;
if (neigh_ifindex_filtered(n->dev, filter->dev_idx) ||
neigh_master_filtered(n->dev, filter->master_idx))
goto next;
err = neigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq,
RTM_NEWNEIGH, flags);
if (err < 0)
goto out;
next:
idx++;
}
}
out:
cb->args[1] = h;
cb->args[2] = idx;
return err;
}
static int pneigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
struct netlink_callback *cb,
struct neigh_dump_filter *filter)
{
struct pneigh_entry *n;
struct net *net = sock_net(skb->sk);
int err = 0, h, s_h = cb->args[3];
int idx, s_idx = idx = cb->args[4];
unsigned int flags = NLM_F_MULTI;
if (filter->dev_idx || filter->master_idx)
flags |= NLM_F_DUMP_FILTERED;
read_lock_bh(&tbl->lock);
for (h = s_h; h <= PNEIGH_HASHMASK; h++) {
if (h > s_h)
s_idx = 0;
for (n = tbl->phash_buckets[h], idx = 0; n; n = n->next) {
if (idx < s_idx || pneigh_net(n) != net)
goto next;
if (neigh_ifindex_filtered(n->dev, filter->dev_idx) ||
neigh_master_filtered(n->dev, filter->master_idx))
goto next;
err = pneigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq,
RTM_NEWNEIGH, flags, tbl);
if (err < 0) {
read_unlock_bh(&tbl->lock);
goto out;
}
next:
idx++;
}
}
read_unlock_bh(&tbl->lock);
out:
cb->args[3] = h;
cb->args[4] = idx;
return err;
}
static int neigh_valid_dump_req(const struct nlmsghdr *nlh,
bool strict_check,
struct neigh_dump_filter *filter,
struct netlink_ext_ack *extack)
{
struct nlattr *tb[NDA_MAX + 1];
int err, i;
if (strict_check) {
struct ndmsg *ndm;
if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) {
NL_SET_ERR_MSG(extack, "Invalid header for neighbor dump request");
return -EINVAL;
}
ndm = nlmsg_data(nlh);
if (ndm->ndm_pad1 || ndm->ndm_pad2 || ndm->ndm_ifindex ||
ndm->ndm_state || ndm->ndm_type) {
NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor dump request");
return -EINVAL;
}
if (ndm->ndm_flags & ~NTF_PROXY) {
NL_SET_ERR_MSG(extack, "Invalid flags in header for neighbor dump request");
return -EINVAL;
}
err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct ndmsg),
tb, NDA_MAX, nda_policy,
extack);
} else {
err = nlmsg_parse_deprecated(nlh, sizeof(struct ndmsg), tb,
NDA_MAX, nda_policy, extack);
}
if (err < 0)
return err;
for (i = 0; i <= NDA_MAX; ++i) {
if (!tb[i])
continue;
/* all new attributes should require strict_check */
switch (i) {
case NDA_IFINDEX:
filter->dev_idx = nla_get_u32(tb[i]);
break;
case NDA_MASTER:
filter->master_idx = nla_get_u32(tb[i]);
break;
default:
if (strict_check) {
NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor dump request");
return -EINVAL;
}
}
}
return 0;
}
static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
{
const struct nlmsghdr *nlh = cb->nlh;
struct neigh_dump_filter filter = {};
struct neigh_table *tbl;
int t, family, s_t;
int proxy = 0;
int err;
family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family;
/* check for full ndmsg structure presence, family member is
* the same for both structures
*/
if (nlmsg_len(nlh) >= sizeof(struct ndmsg) &&
((struct ndmsg *)nlmsg_data(nlh))->ndm_flags == NTF_PROXY)
proxy = 1;
err = neigh_valid_dump_req(nlh, cb->strict_check, &filter, cb->extack);
if (err < 0 && cb->strict_check)
return err;
s_t = cb->args[0];
rcu_read_lock();
for (t = 0; t < NEIGH_NR_TABLES; t++) {
tbl = rcu_dereference(neigh_tables[t]);
if (!tbl)
continue;
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 (proxy)
err = pneigh_dump_table(tbl, skb, cb, &filter);
else
err = neigh_dump_table(tbl, skb, cb, &filter);
if (err < 0)
break;
}
rcu_read_unlock();
cb->args[0] = t;
return err;
}
static int neigh_valid_get_req(const struct nlmsghdr *nlh,
struct neigh_table **tbl,
void **dst, int *dev_idx, u8 *ndm_flags,
struct netlink_ext_ack *extack)
{
struct nlattr *tb[NDA_MAX + 1];
struct ndmsg *ndm;
int err, i;
if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) {
NL_SET_ERR_MSG(extack, "Invalid header for neighbor get request");
return -EINVAL;
}
ndm = nlmsg_data(nlh);
if (ndm->ndm_pad1 || ndm->ndm_pad2 || ndm->ndm_state ||
ndm->ndm_type) {
NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor get request");
return -EINVAL;
}
if (ndm->ndm_flags & ~NTF_PROXY) {
NL_SET_ERR_MSG(extack, "Invalid flags in header for neighbor get request");
return -EINVAL;
}
err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct ndmsg), tb,
NDA_MAX, nda_policy, extack);
if (err < 0)
return err;
*ndm_flags = ndm->ndm_flags;
*dev_idx = ndm->ndm_ifindex;
*tbl = neigh_find_table(ndm->ndm_family);
if (*tbl == NULL) {
NL_SET_ERR_MSG(extack, "Unsupported family in header for neighbor get request");
return -EAFNOSUPPORT;
}
for (i = 0; i <= NDA_MAX; ++i) {
if (!tb[i])
continue;
switch (i) {
case NDA_DST:
if (nla_len(tb[i]) != (int)(*tbl)->key_len) {
NL_SET_ERR_MSG(extack, "Invalid network address in neighbor get request");
return -EINVAL;
}
*dst = nla_data(tb[i]);
break;
default:
NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor get request");
return -EINVAL;
}
}
return 0;
}
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 */
+ nla_total_size(4) /* NDA_FLAGS_EXT */
+ nla_total_size(1); /* NDA_PROTOCOL */
}
static int neigh_get_reply(struct net *net, struct neighbour *neigh,
u32 pid, u32 seq)
{
struct sk_buff *skb;
int err = 0;
skb = nlmsg_new(neigh_nlmsg_size(), GFP_KERNEL);
if (!skb)
return -ENOBUFS;
err = neigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0);
if (err) {
kfree_skb(skb);
goto errout;
}
err = rtnl_unicast(skb, net, pid);
errout:
return err;
}
static inline size_t pneigh_nlmsg_size(void)
{
return NLMSG_ALIGN(sizeof(struct ndmsg))
+ nla_total_size(MAX_ADDR_LEN) /* NDA_DST */
+ nla_total_size(4) /* NDA_FLAGS_EXT */
+ nla_total_size(1); /* NDA_PROTOCOL */
}
static int pneigh_get_reply(struct net *net, struct pneigh_entry *neigh,
u32 pid, u32 seq, struct neigh_table *tbl)
{
struct sk_buff *skb;
int err = 0;
skb = nlmsg_new(pneigh_nlmsg_size(), GFP_KERNEL);
if (!skb)
return -ENOBUFS;
err = pneigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0, tbl);
if (err) {
kfree_skb(skb);
goto errout;
}
err = rtnl_unicast(skb, net, pid);
errout:
return err;
}
static int neigh_get(struct sk_buff *in_skb, struct nlmsghdr *nlh,
struct netlink_ext_ack *extack)
{
struct net *net = sock_net(in_skb->sk);
struct net_device *dev = NULL;
struct neigh_table *tbl = NULL;
struct neighbour *neigh;
void *dst = NULL;
u8 ndm_flags = 0;
int dev_idx = 0;
int err;
err = neigh_valid_get_req(nlh, &tbl, &dst, &dev_idx, &ndm_flags,
extack);
if (err < 0)
return err;
if (dev_idx) {
dev = __dev_get_by_index(net, dev_idx);
if (!dev) {
NL_SET_ERR_MSG(extack, "Unknown device ifindex");
return -ENODEV;
}
}
if (!dst) {
NL_SET_ERR_MSG(extack, "Network address not specified");
return -EINVAL;
}
if (ndm_flags & NTF_PROXY) {
struct pneigh_entry *pn;
pn = pneigh_lookup(tbl, net, dst, dev, 0);
if (!pn) {
NL_SET_ERR_MSG(extack, "Proxy neighbour entry not found");
return -ENOENT;
}
return pneigh_get_reply(net, pn, NETLINK_CB(in_skb).portid,
nlh->nlmsg_seq, tbl);
}
if (!dev) {
NL_SET_ERR_MSG(extack, "No device specified");
return -EINVAL;
}
neigh = neigh_lookup(tbl, dst, dev);
if (!neigh) {
NL_SET_ERR_MSG(extack, "Neighbour entry not found");
return -ENOENT;
}
err = neigh_get_reply(net, neigh, NETLINK_CB(in_skb).portid,
nlh->nlmsg_seq);
neigh_release(neigh);
return err;
}
void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie)
{
int chain;
struct neigh_hash_table *nht;
rcu_read_lock();
nht = rcu_dereference(tbl->nht);
read_lock_bh(&tbl->lock); /* avoid resizes */
for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
struct neighbour *n;
neigh_for_each_in_bucket(n, &nht->hash_heads[chain])
cb(n, cookie);
}
read_unlock_bh(&tbl->lock);
rcu_read_unlock();
}
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 *))
{
struct neigh_hash_table *nht;
int chain;
nht = rcu_dereference_protected(tbl->nht,
lockdep_is_held(&tbl->lock));
for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
struct hlist_node *tmp;
struct neighbour *n;
neigh_for_each_in_bucket_safe(n, tmp, &nht->hash_heads[chain]) {
int release;
write_lock(&n->lock);
release = cb(n);
if (release) {
hlist_del_rcu(&n->hash);
hlist_del_rcu(&n->dev_list);
neigh_mark_dead(n);
}
write_unlock(&n->lock);
if (release)
neigh_cleanup_and_release(n);
}
}
}
EXPORT_SYMBOL(__neigh_for_each_release);
int neigh_xmit(int index, struct net_device *dev,
const void *addr, struct sk_buff *skb)
{
int err = -EAFNOSUPPORT;
if (likely(index < NEIGH_NR_TABLES)) {
struct neigh_table *tbl;
struct neighbour *neigh;
rcu_read_lock();
tbl = rcu_dereference(neigh_tables[index]);
if (!tbl)
goto out_unlock;
if (index == NEIGH_ARP_TABLE) {
u32 key = *((u32 *)addr);
neigh = __ipv4_neigh_lookup_noref(dev, key);
} else {
neigh = __neigh_lookup_noref(tbl, addr, dev);
}
if (!neigh)
neigh = __neigh_create(tbl, addr, dev, false);
err = PTR_ERR(neigh);
if (IS_ERR(neigh)) {
rcu_read_unlock();
goto out_kfree_skb;
}
err = READ_ONCE(neigh->output)(neigh, skb);
out_unlock:
rcu_read_unlock();
}
else if (index == NEIGH_LINK_TABLE) {
err = dev_hard_header(skb, dev, ntohs(skb->protocol),
addr, NULL, skb->len);
if (err < 0)
goto out_kfree_skb;
err = dev_queue_xmit(skb);
}
out:
return err;
out_kfree_skb:
kfree_skb(skb);
goto out;
}
EXPORT_SYMBOL(neigh_xmit);
#ifdef CONFIG_PROC_FS
static struct neighbour *neigh_get_valid(struct seq_file *seq,
struct neighbour *n,
loff_t *pos)
{
struct neigh_seq_state *state = seq->private;
struct net *net = seq_file_net(seq);
if (!net_eq(dev_net(n->dev), net))
return NULL;
if (state->neigh_sub_iter) {
loff_t fakep = 0;
void *v;
v = state->neigh_sub_iter(state, n, pos ? pos : &fakep);
if (!v)
return NULL;
if (pos)
return v;
}
if (!(state->flags & NEIGH_SEQ_SKIP_NOARP))
return n;
if (READ_ONCE(n->nud_state) & ~NUD_NOARP)
return n;
return NULL;
}
static struct neighbour *neigh_get_first(struct seq_file *seq)
{
struct neigh_seq_state *state = seq->private;
struct neigh_hash_table *nht = state->nht;
struct neighbour *n, *tmp;
state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
while (++state->bucket < (1 << nht->hash_shift)) {
neigh_for_each_in_bucket(n, &nht->hash_heads[state->bucket]) {
tmp = neigh_get_valid(seq, n, NULL);
if (tmp)
return tmp;
}
}
return NULL;
}
static struct neighbour *neigh_get_next(struct seq_file *seq,
struct neighbour *n,
loff_t *pos)
{
struct neigh_seq_state *state = seq->private;
struct neighbour *tmp;
if (state->neigh_sub_iter) {
void *v = state->neigh_sub_iter(state, n, pos);
if (v)
return n;
}
hlist_for_each_entry_continue(n, hash) {
tmp = neigh_get_valid(seq, n, pos);
if (tmp) {
n = tmp;
goto out;
}
}
n = neigh_get_first(seq);
out:
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) {
--(*pos);
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;
struct net *net = seq_file_net(seq);
struct neigh_table *tbl = state->tbl;
struct pneigh_entry *pn = NULL;
int bucket;
state->flags |= NEIGH_SEQ_IS_PNEIGH;
for (bucket = 0; bucket <= PNEIGH_HASHMASK; bucket++) {
pn = tbl->phash_buckets[bucket];
while (pn && !net_eq(pneigh_net(pn), net))
pn = pn->next;
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;
struct net *net = seq_file_net(seq);
struct neigh_table *tbl = state->tbl;
do {
pn = pn->next;
} while (pn && !net_eq(pneigh_net(pn), net));
while (!pn) {
if (++state->bucket > PNEIGH_HASHMASK)
break;
pn = tbl->phash_buckets[state->bucket];
while (pn && !net_eq(pneigh_net(pn), net))
pn = pn->next;
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) {
--(*pos);
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;
loff_t idxpos = *pos;
rc = neigh_get_idx(seq, &idxpos);
if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY))
rc = pneigh_get_idx(seq, &idxpos);
return rc;
}
void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
__acquires(tbl->lock)
__acquires(rcu)
{
struct neigh_seq_state *state = seq->private;
state->tbl = tbl;
state->bucket = -1;
state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
rcu_read_lock();
state->nht = rcu_dereference(tbl->nht);
read_lock_bh(&tbl->lock);
return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
}
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) {
rc = neigh_get_first(seq);
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)
__releases(tbl->lock)
__releases(rcu)
{
struct neigh_seq_state *state = seq->private;
struct neigh_table *tbl = state->tbl;
read_unlock_bh(&tbl->lock);
rcu_read_unlock();
}
EXPORT_SYMBOL(neigh_seq_stop);
/* statistics via seq_file */
static void *neigh_stat_seq_start(struct seq_file *seq, loff_t *pos)
{
struct neigh_table *tbl = pde_data(file_inode(seq->file));
int cpu;
if (*pos == 0)
return SEQ_START_TOKEN;
for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
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)
{
struct neigh_table *tbl = pde_data(file_inode(seq->file));
int cpu;
for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
if (!cpu_possible(cpu))
continue;
*pos = cpu+1;
return per_cpu_ptr(tbl->stats, cpu);
}
(*pos)++;
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)
{
struct neigh_table *tbl = pde_data(file_inode(seq->file));
struct neigh_statistics *st = v;
if (v == SEQ_START_TOKEN) {
seq_puts(seq, "entries allocs destroys hash_grows lookups hits res_failed rcv_probes_mcast rcv_probes_ucast periodic_gc_runs forced_gc_runs unresolved_discards table_fulls\n");
return 0;
}
seq_printf(seq, "%08x %08lx %08lx %08lx %08lx %08lx %08lx "
"%08lx %08lx %08lx "
"%08lx %08lx %08lx\n",
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,
st->forced_gc_runs,
st->unres_discards,
st->table_fulls
);
return 0;
}
static const struct seq_operations neigh_stat_seq_ops = {
.start = neigh_stat_seq_start,
.next = neigh_stat_seq_next,
.stop = neigh_stat_seq_stop,
.show = neigh_stat_seq_show,
};
#endif /* CONFIG_PROC_FS */
static void __neigh_notify(struct neighbour *n, int type, int flags,
u32 pid)
{
struct net *net = dev_net(n->dev);
struct sk_buff *skb;
int err = -ENOBUFS;
skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);
if (skb == NULL)
goto errout;
err = neigh_fill_info(skb, n, pid, 0, type, flags);
if (err < 0) {
/* -EMSGSIZE implies BUG in neigh_nlmsg_size() */
WARN_ON(err == -EMSGSIZE);
kfree_skb(skb);
goto errout;
}
rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
return;
errout:
rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
}
void neigh_app_ns(struct neighbour *n)
{
__neigh_notify(n, RTM_GETNEIGH, NLM_F_REQUEST, 0);
}
EXPORT_SYMBOL(neigh_app_ns);
#ifdef CONFIG_SYSCTL
static int unres_qlen_max = INT_MAX / SKB_TRUESIZE(ETH_FRAME_LEN);
static int proc_unres_qlen(const struct ctl_table *ctl, int write,
void *buffer, size_t *lenp, loff_t *ppos)
{
int size, ret;
struct ctl_table tmp = *ctl;
tmp.extra1 = SYSCTL_ZERO;
tmp.extra2 = &unres_qlen_max;
tmp.data = &size;
size = *(int *)ctl->data / SKB_TRUESIZE(ETH_FRAME_LEN);
ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
if (write && !ret)
*(int *)ctl->data = size * SKB_TRUESIZE(ETH_FRAME_LEN);
return ret;
}
static void neigh_copy_dflt_parms(struct net *net, struct neigh_parms *p,
int index)
{
struct net_device *dev;
int family = neigh_parms_family(p);
rcu_read_lock();
for_each_netdev_rcu(net, dev) {
struct neigh_parms *dst_p =
neigh_get_dev_parms_rcu(dev, family);
if (dst_p && !test_bit(index, dst_p->data_state))
dst_p->data[index] = p->data[index];
}
rcu_read_unlock();
}
static void neigh_proc_update(const struct ctl_table *ctl, int write)
{
struct net_device *dev = ctl->extra1;
struct neigh_parms *p = ctl->extra2;
struct net *net = neigh_parms_net(p);
int index = (int *) ctl->data - p->data;
if (!write)
return;
set_bit(index, p->data_state);
if (index == NEIGH_VAR_DELAY_PROBE_TIME)
call_netevent_notifiers(NETEVENT_DELAY_PROBE_TIME_UPDATE, p);
if (!dev) /* NULL dev means this is default value */
neigh_copy_dflt_parms(net, p, index);
}
static int neigh_proc_dointvec_zero_intmax(const struct ctl_table *ctl, int write,
void *buffer, size_t *lenp,
loff_t *ppos)
{
struct ctl_table tmp = *ctl;
int ret;
tmp.extra1 = SYSCTL_ZERO;
tmp.extra2 = SYSCTL_INT_MAX;
ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
neigh_proc_update(ctl, write);
return ret;
}
static int neigh_proc_dointvec_ms_jiffies_positive(const struct ctl_table *ctl, int write,
void *buffer, size_t *lenp, loff_t *ppos)
{
struct ctl_table tmp = *ctl;
int ret;
int min = msecs_to_jiffies(1);
tmp.extra1 = &min;
tmp.extra2 = NULL;
ret = proc_dointvec_ms_jiffies_minmax(&tmp, write, buffer, lenp, ppos);
neigh_proc_update(ctl, write);
return ret;
}
int neigh_proc_dointvec(const struct ctl_table *ctl, int write, void *buffer,
size_t *lenp, loff_t *ppos)
{
int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
neigh_proc_update(ctl, write);
return ret;
}
EXPORT_SYMBOL(neigh_proc_dointvec);
int neigh_proc_dointvec_jiffies(const struct ctl_table *ctl, int write, void *buffer,
size_t *lenp, loff_t *ppos)
{
int ret = proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
neigh_proc_update(ctl, write);
return ret;
}
EXPORT_SYMBOL(neigh_proc_dointvec_jiffies);
static int neigh_proc_dointvec_userhz_jiffies(const struct ctl_table *ctl, int write,
void *buffer, size_t *lenp,
loff_t *ppos)
{
int ret = proc_dointvec_userhz_jiffies(ctl, write, buffer, lenp, ppos);
neigh_proc_update(ctl, write);
return ret;
}
int neigh_proc_dointvec_ms_jiffies(const struct ctl_table *ctl, int write,
void *buffer, size_t *lenp, loff_t *ppos)
{
int ret = proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
neigh_proc_update(ctl, write);
return ret;
}
EXPORT_SYMBOL(neigh_proc_dointvec_ms_jiffies);
static int neigh_proc_dointvec_unres_qlen(const struct ctl_table *ctl, int write,
void *buffer, size_t *lenp,
loff_t *ppos)
{
int ret = proc_unres_qlen(ctl, write, buffer, lenp, ppos);
neigh_proc_update(ctl, write);
return ret;
}
static int neigh_proc_base_reachable_time(const struct ctl_table *ctl, int write,
void *buffer, size_t *lenp,
loff_t *ppos)
{
struct neigh_parms *p = ctl->extra2;
int ret;
if (strcmp(ctl->procname, "base_reachable_time") == 0)
ret = neigh_proc_dointvec_jiffies(ctl, write, buffer, lenp, ppos);
else if (strcmp(ctl->procname, "base_reachable_time_ms") == 0)
ret = neigh_proc_dointvec_ms_jiffies(ctl, write, buffer, lenp, ppos);
else
ret = -1;
if (write && ret == 0) {
/* update reachable_time as well, otherwise, the change will
* only be effective after the next time neigh_periodic_work
* decides to recompute it
*/
p->reachable_time =
neigh_rand_reach_time(NEIGH_VAR(p, BASE_REACHABLE_TIME));
}
return ret;
}
#define NEIGH_PARMS_DATA_OFFSET(index) \
(&((struct neigh_parms *) 0)->data[index])
#define NEIGH_SYSCTL_ENTRY(attr, data_attr, name, mval, proc) \
[NEIGH_VAR_ ## attr] = { \
.procname = name, \
.data = NEIGH_PARMS_DATA_OFFSET(NEIGH_VAR_ ## data_attr), \
.maxlen = sizeof(int), \
.mode = mval, \
.proc_handler = proc, \
}
#define NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(attr, name) \
NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_zero_intmax)
#define NEIGH_SYSCTL_JIFFIES_ENTRY(attr, name) \
NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_jiffies)
#define NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(attr, name) \
NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_userhz_jiffies)
#define NEIGH_SYSCTL_MS_JIFFIES_POSITIVE_ENTRY(attr, name) \
NEIGH_SYSCTL_ENTRY(attr, attr, name, 0644, neigh_proc_dointvec_ms_jiffies_positive)
#define NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(attr, data_attr, name) \
NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_ms_jiffies)
#define NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(attr, data_attr, name) \
NEIGH_SYSCTL_ENTRY(attr, data_attr, name, 0644, neigh_proc_dointvec_unres_qlen)
static struct neigh_sysctl_table {
struct ctl_table_header *sysctl_header;
struct ctl_table neigh_vars[NEIGH_VAR_MAX];
} neigh_sysctl_template __read_mostly = {
.neigh_vars = {
NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_PROBES, "mcast_solicit"),
NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(UCAST_PROBES, "ucast_solicit"),
NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(APP_PROBES, "app_solicit"),
NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_REPROBES, "mcast_resolicit"),
NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(RETRANS_TIME, "retrans_time"),
NEIGH_SYSCTL_JIFFIES_ENTRY(BASE_REACHABLE_TIME, "base_reachable_time"),
NEIGH_SYSCTL_JIFFIES_ENTRY(DELAY_PROBE_TIME, "delay_first_probe_time"),
NEIGH_SYSCTL_MS_JIFFIES_POSITIVE_ENTRY(INTERVAL_PROBE_TIME_MS,
"interval_probe_time_ms"),
NEIGH_SYSCTL_JIFFIES_ENTRY(GC_STALETIME, "gc_stale_time"),
NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(QUEUE_LEN_BYTES, "unres_qlen_bytes"),
NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(PROXY_QLEN, "proxy_qlen"),
NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(ANYCAST_DELAY, "anycast_delay"),
NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(PROXY_DELAY, "proxy_delay"),
NEIGH_SYSCTL_USERHZ_JIFFIES_ENTRY(LOCKTIME, "locktime"),
NEIGH_SYSCTL_UNRES_QLEN_REUSED_ENTRY(QUEUE_LEN, QUEUE_LEN_BYTES, "unres_qlen"),
NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(RETRANS_TIME_MS, RETRANS_TIME, "retrans_time_ms"),
NEIGH_SYSCTL_MS_JIFFIES_REUSED_ENTRY(BASE_REACHABLE_TIME_MS, BASE_REACHABLE_TIME, "base_reachable_time_ms"),
[NEIGH_VAR_GC_INTERVAL] = {
.procname = "gc_interval",
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
[NEIGH_VAR_GC_THRESH1] = {
.procname = "gc_thresh1",
.maxlen = sizeof(int),
.mode = 0644,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_INT_MAX,
.proc_handler = proc_dointvec_minmax,
},
[NEIGH_VAR_GC_THRESH2] = {
.procname = "gc_thresh2",
.maxlen = sizeof(int),
.mode = 0644,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_INT_MAX,
.proc_handler = proc_dointvec_minmax,
},
[NEIGH_VAR_GC_THRESH3] = {
.procname = "gc_thresh3",
.maxlen = sizeof(int),
.mode = 0644,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_INT_MAX,
.proc_handler = proc_dointvec_minmax,
},
},
};
int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
proc_handler *handler)
{
int i;
struct neigh_sysctl_table *t;
const char *dev_name_source;
char neigh_path[ sizeof("net//neigh/") + IFNAMSIZ + IFNAMSIZ ];
char *p_name;
size_t neigh_vars_size;
t = kmemdup(&neigh_sysctl_template, sizeof(*t), GFP_KERNEL_ACCOUNT);
if (!t)
goto err;
for (i = 0; i < NEIGH_VAR_GC_INTERVAL; i++) {
t->neigh_vars[i].data += (long) p;
t->neigh_vars[i].extra1 = dev;
t->neigh_vars[i].extra2 = p;
}
neigh_vars_size = ARRAY_SIZE(t->neigh_vars);
if (dev) {
dev_name_source = dev->name;
/* Terminate the table early */
neigh_vars_size = NEIGH_VAR_BASE_REACHABLE_TIME_MS + 1;
} else {
struct neigh_table *tbl = p->tbl;
dev_name_source = "default";
t->neigh_vars[NEIGH_VAR_GC_INTERVAL].data = &tbl->gc_interval;
t->neigh_vars[NEIGH_VAR_GC_THRESH1].data = &tbl->gc_thresh1;
t->neigh_vars[NEIGH_VAR_GC_THRESH2].data = &tbl->gc_thresh2;
t->neigh_vars[NEIGH_VAR_GC_THRESH3].data = &tbl->gc_thresh3;
}
if (handler) {
/* RetransTime */
t->neigh_vars[NEIGH_VAR_RETRANS_TIME].proc_handler = handler;
/* ReachableTime */
t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler = handler;
/* RetransTime (in milliseconds)*/
t->neigh_vars[NEIGH_VAR_RETRANS_TIME_MS].proc_handler = handler;
/* ReachableTime (in milliseconds) */
t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler = handler;
} else {
/* Those handlers will update p->reachable_time after
* base_reachable_time(_ms) is set to ensure the new timer starts being
* applied after the next neighbour update instead of waiting for
* neigh_periodic_work to update its value (can be multiple minutes)
* So any handler that replaces them should do this as well
*/
/* ReachableTime */
t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME].proc_handler =
neigh_proc_base_reachable_time;
/* ReachableTime (in milliseconds) */
t->neigh_vars[NEIGH_VAR_BASE_REACHABLE_TIME_MS].proc_handler =
neigh_proc_base_reachable_time;
}
switch (neigh_parms_family(p)) {
case AF_INET:
p_name = "ipv4";
break;
case AF_INET6:
p_name = "ipv6";
break;
default:
BUG();
}
snprintf(neigh_path, sizeof(neigh_path), "net/%s/neigh/%s",
p_name, dev_name_source);
t->sysctl_header = register_net_sysctl_sz(neigh_parms_net(p),
neigh_path, t->neigh_vars,
neigh_vars_size);
if (!t->sysctl_header)
goto free;
p->sysctl_table = t;
return 0;
free:
kfree(t);
err:
return -ENOBUFS;
}
EXPORT_SYMBOL(neigh_sysctl_register);
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_net_sysctl_table(t->sysctl_header);
kfree(t);
}
}
EXPORT_SYMBOL(neigh_sysctl_unregister);
#endif /* CONFIG_SYSCTL */
static const struct rtnl_msg_handler neigh_rtnl_msg_handlers[] __initconst = {
{.msgtype = RTM_NEWNEIGH, .doit = neigh_add},
{.msgtype = RTM_DELNEIGH, .doit = neigh_delete},
{.msgtype = RTM_GETNEIGH, .doit = neigh_get, .dumpit = neigh_dump_info,
.flags = RTNL_FLAG_DUMP_UNLOCKED},
{.msgtype = RTM_GETNEIGHTBL, .dumpit = neightbl_dump_info},
{.msgtype = RTM_SETNEIGHTBL, .doit = neightbl_set},
};
static int __init neigh_init(void)
{
rtnl_register_many(neigh_rtnl_msg_handlers);
return 0;
}
subsys_initcall(neigh_init);
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