diff options
Diffstat (limited to 'net/core/neighbour.c')
| -rw-r--r-- | net/core/neighbour.c | 2362 |
1 files changed, 2362 insertions, 0 deletions
diff --git a/net/core/neighbour.c b/net/core/neighbour.c new file mode 100644 index 0000000..0a2f67b --- /dev/null +++ b/net/core/neighbour.c @@ -0,0 +1,2362 @@ +/* + * 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 + */ + +#include <linux/config.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/socket.h> +#include <linux/sched.h> +#include <linux/netdevice.h> +#include <linux/proc_fs.h> +#ifdef CONFIG_SYSCTL +#include <linux/sysctl.h> +#endif +#include <linux/times.h> +#include <net/neighbour.h> +#include <net/dst.h> +#include <net/sock.h> +#include <linux/rtnetlink.h> +#include <linux/random.h> + +#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); +#ifdef CONFIG_ARPD +static void neigh_app_notify(struct neighbour *n); +#endif +static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev); +void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev); + +static struct neigh_table *neigh_tables; +static struct file_operations neigh_stat_seq_fops; + +/* + 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; +} + +/* + * 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 ? (net_random() % base) + (base >> 1) : 0); +} + + +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); + neigh_release(n); + continue; + } + write_unlock(&n->lock); + np = &n->next; + } + } + + tbl->last_flush = jiffies; + + write_unlock_bh(&tbl->lock); + + return shrunk; +} + +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); + } +} + +void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev) +{ + int i; + + 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) { + if (dev && n->dev != dev) { + np = &n->next; + continue; + } + *np = n->next; + write_lock_bh(&n->lock); + n->dead = 1; + neigh_del_timer(n); + write_unlock_bh(&n->lock); + neigh_release(n); + } + } + + write_unlock_bh(&tbl->lock); +} + +int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev) +{ + int i; + + write_lock_bh(&tbl->lock); + + 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); + neigh_release(n); + } + } + + pneigh_ifdown(tbl, dev); + write_unlock_bh(&tbl->lock); + + del_timer_sync(&tbl->proxy_timer); + pneigh_queue_purge(&tbl->proxy_queue); + return 0; +} + +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; + } + + n = kmem_cache_alloc(tbl->kmem_cachep, SLAB_ATOMIC); + if (!n) + goto out_entries; + + memset(n, 0, tbl->entry_size); + + 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); + init_timer(&n->timer); + n->timer.function = neigh_timer_handler; + n->timer.data = (unsigned long)n; + + 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) { + ret = kmalloc(size, GFP_ATOMIC); + } else { + ret = (struct neighbour **) + __get_free_pages(GFP_ATOMIC, get_order(size)); + } + if (ret) + memset(ret, 0, size); + + 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); + + BUG_ON(new_entries & (new_entries - 1)); + 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; + u32 hash_val = tbl->hash(pkey, dev) & tbl->hash_mask; + + NEIGH_CACHE_STAT_INC(tbl, lookups); + + read_lock_bh(&tbl->lock); + for (n = tbl->hash_buckets[hash_val]; n; n = n->next) { + 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; +} + +struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, const void *pkey) +{ + struct neighbour *n; + int key_len = tbl->key_len; + u32 hash_val = tbl->hash(pkey, NULL) & tbl->hash_mask; + + NEIGH_CACHE_STAT_INC(tbl, lookups); + + read_lock_bh(&tbl->lock); + for (n = tbl->hash_buckets[hash_val]; n; n = n->next) { + if (!memcmp(n->primary_key, pkey, key_len)) { + neigh_hold(n); + NEIGH_CACHE_STAT_INC(tbl, hits); + break; + } + } + read_unlock_bh(&tbl->lock); + return n; +} + +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; +} + +struct pneigh_entry * pneigh_lookup(struct neigh_table *tbl, const void *pkey, + struct net_device *dev, int creat) +{ + struct pneigh_entry *n; + int key_len = tbl->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; + + read_lock_bh(&tbl->lock); + + for (n = tbl->phash_buckets[hash_val]; n; n = n->next) { + if (!memcmp(n->key, pkey, key_len) && + (n->dev == dev || !n->dev)) { + read_unlock_bh(&tbl->lock); + goto out; + } + } + read_unlock_bh(&tbl->lock); + n = NULL; + if (!creat) + goto out; + + n = kmalloc(sizeof(*n) + key_len, GFP_KERNEL); + if (!n) + goto out; + + 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); + 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; +} + + +int pneigh_delete(struct neigh_table *tbl, const void *pkey, + struct net_device *dev) +{ + struct pneigh_entry *n, **np; + int key_len = tbl->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; + + 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) { + *np = n->next; + write_unlock_bh(&tbl->lock); + if (tbl->pdestructor) + tbl->pdestructor(n); + if (n->dev) + dev_put(n->dev); + 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); + kfree(n); + continue; + } + np = &n->next; + } + } + return -ENOENT; +} + + +/* + * 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; + write_lock_bh(&hh->hh_lock); + hh->hh_output = neigh_blackhole; + write_unlock_bh(&hh->hh_lock); + if (atomic_dec_and_test(&hh->hh_refcnt)) + kfree(hh); + } + + if (neigh->ops && neigh->ops->destructor) + (neigh->ops->destructor)(neigh); + + 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); +} + +/* 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; +} + +static void neigh_periodic_timer(unsigned long arg) +{ + struct neigh_table *tbl = (struct neigh_table *)arg; + struct neighbour *n, **np; + unsigned long expire, now = jiffies; + + NEIGH_CACHE_STAT_INC(tbl, periodic_gc_runs); + + write_lock(&tbl->lock); + + /* + * periodically recompute ReachableTime from random function + */ + + if (time_after(now, tbl->last_rand + 300 * HZ)) { + struct neigh_parms *p; + tbl->last_rand = now; + for (p = &tbl->parms; p; p = p->next) + p->reachable_time = + neigh_rand_reach_time(p->base_reachable_time); + } + + np = &tbl->hash_buckets[tbl->hash_chain_gc]; + tbl->hash_chain_gc = ((tbl->hash_chain_gc + 1) & tbl->hash_mask); + + while ((n = *np) != NULL) { + unsigned int state; + + write_lock(&n->lock); + + state = n->nud_state; + if (state & (NUD_PERMANENT | NUD_IN_TIMER)) { + write_unlock(&n->lock); + goto next_elt; + } + + if (time_before(n->used, n->confirmed)) + n->used = n->confirmed; + + if (atomic_read(&n->refcnt) == 1 && + (state == NUD_FAILED || + time_after(now, n->used + n->parms->gc_staletime))) { + *np = n->next; + n->dead = 1; + write_unlock(&n->lock); + neigh_release(n); + continue; + } + write_unlock(&n->lock); + +next_elt: + np = &n->next; + } + + /* 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. + */ + expire = tbl->parms.base_reachable_time >> 1; + expire /= (tbl->hash_mask + 1); + if (!expire) + expire = 1; + + mod_timer(&tbl->gc_timer, now + expire); + + write_unlock(&tbl->lock); +} + +static __inline__ int neigh_max_probes(struct neighbour *n) +{ + struct neigh_parms *p = n->parms; + return (n->nud_state & NUD_PROBE ? + p->ucast_probes : + p->ucast_probes + p->app_probes + p->mcast_probes); +} + + +/* 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) { + if (time_before_eq(now, + 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; + neigh_suspect(neigh); + next = now + neigh->parms->delay_probe_time; + } else { + NEIGH_PRINTK2("neigh %p is suspected.\n", neigh); + neigh->nud_state = NUD_STALE; + neigh_suspect(neigh); + } + } else if (state & NUD_DELAY) { + if (time_before_eq(now, + neigh->confirmed + neigh->parms->delay_probe_time)) { + NEIGH_PRINTK2("neigh %p is now reachable.\n", neigh); + neigh->nud_state = NUD_REACHABLE; + neigh_connect(neigh); + next = neigh->confirmed + neigh->parms->reachable_time; + } else { + NEIGH_PRINTK2("neigh %p is probed.\n", neigh); + neigh->nud_state = NUD_PROBE; + 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)) { + struct sk_buff *skb; + + neigh->nud_state = NUD_FAILED; + notify = 1; + NEIGH_CACHE_STAT_INC(neigh->tbl, res_failed); + NEIGH_PRINTK2("neigh %p is failed.\n", neigh); + + /* 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); + } + + if (neigh->nud_state & NUD_IN_TIMER) { + neigh_hold(neigh); + if (time_before(next, jiffies + HZ/2)) + next = jiffies + HZ/2; + neigh->timer.expires = next; + add_timer(&neigh->timer); + } + if (neigh->nud_state & (NUD_INCOMPLETE | NUD_PROBE)) { + struct sk_buff *skb = skb_peek(&neigh->arp_queue); + /* keep skb alive even if arp_queue overflows */ + if (skb) + skb_get(skb); + write_unlock(&neigh->lock); + neigh->ops->solicit(neigh, skb); + atomic_inc(&neigh->probes); + if (skb) + kfree_skb(skb); + } else { +out: + write_unlock(&neigh->lock); + } + +#ifdef CONFIG_ARPD + if (notify && neigh->parms->app_probes) + neigh_app_notify(neigh); +#endif + 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; + + 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; + neigh_hold(neigh); + neigh->timer.expires = now + 1; + add_timer(&neigh->timer); + } else { + neigh->nud_state = NUD_FAILED; + write_unlock_bh(&neigh->lock); + + if (skb) + kfree_skb(skb); + return 1; + } + } else if (neigh->nud_state & NUD_STALE) { + NEIGH_PRINTK2("neigh %p is delayed.\n", neigh); + neigh_hold(neigh); + neigh->nud_state = NUD_DELAY; + neigh->timer.expires = jiffies + neigh->parms->delay_probe_time; + add_timer(&neigh->timer); + } + + if (neigh->nud_state == NUD_INCOMPLETE) { + if (skb) { + if (skb_queue_len(&neigh->arp_queue) >= + neigh->parms->queue_len) { + struct sk_buff *buff; + buff = neigh->arp_queue.next; + __skb_unlink(buff, &neigh->arp_queue); + kfree_skb(buff); + } + __skb_queue_tail(&neigh->arp_queue, skb); + } + rc = 1; + } +out_unlock_bh: + write_unlock_bh(&neigh->lock); + return rc; +} + +static __inline__ void neigh_update_hhs(struct neighbour *neigh) +{ + struct hh_cache *hh; + void (*update)(struct hh_cache*, struct net_device*, unsigned char *) = + neigh->dev->header_cache_update; + + if (update) { + for (hh = neigh->hh; hh; hh = hh->hh_next) { + write_lock_bh(&hh->hh_lock); + update(hh, neigh->dev, neigh->ha); + write_unlock_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. + It also allows to retain current state + if lladdr is unchanged. + NEIGH_UPDATE_F_ADMIN means that the change is administrative. + + 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. + */ + +int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, + u32 flags) +{ + u8 old; + int err; +#ifdef CONFIG_ARPD + int notify = 0; +#endif + struct net_device *dev; + int update_isrouter = 0; + + write_lock_bh(&neigh->lock); + + dev = neigh->dev; + old = neigh->nud_state; + err = -EPERM; + + if (!(flags & NEIGH_UPDATE_F_ADMIN) && + (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; +#ifdef CONFIG_ARPD + notify = old & NUD_VALID; +#endif + 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)) + 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); + if (new & NUD_IN_TIMER) { + neigh_hold(neigh); + neigh->timer.expires = jiffies + + ((new & NUD_REACHABLE) ? + neigh->parms->reachable_time : 0); + add_timer(&neigh->timer); + } + 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); +#ifdef CONFIG_ARPD + notify = 1; +#endif + } + 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 :( */ + if (skb->dst && skb->dst->neighbour) + n1 = skb->dst->neighbour; + 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); +#ifdef CONFIG_ARPD + if (notify && neigh->parms->app_probes) + neigh_app_notify(neigh); +#endif + return err; +} + +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); + return neigh; +} + +static void neigh_hh_init(struct neighbour *n, struct dst_entry *dst, + u16 protocol) +{ + 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; + + if (!hh && (hh = kmalloc(sizeof(*hh), GFP_ATOMIC)) != NULL) { + memset(hh, 0, sizeof(struct hh_cache)); + rwlock_init(&hh->hh_lock); + hh->hh_type = protocol; + atomic_set(&hh->hh_refcnt, 0); + hh->hh_next = NULL; + if (dev->hard_header_cache(n, hh)) { + 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; + + __skb_pull(skb, skb->nh.raw - skb->data); + + if (dev->hard_header && + dev->hard_header(skb, dev, ntohs(skb->protocol), NULL, NULL, + skb->len) < 0 && + dev->rebuild_header(skb)) + return 0; + + return dev_queue_xmit(skb); +} + +/* Slow and careful. */ + +int neigh_resolve_output(struct sk_buff *skb) +{ + struct dst_entry *dst = skb->dst; + struct neighbour *neigh; + int rc = 0; + + if (!dst || !(neigh = dst->neighbour)) + goto discard; + + __skb_pull(skb, skb->nh.raw - skb->data); + + if (!neigh_event_send(neigh, skb)) { + int err; + struct net_device *dev = neigh->dev; + if (dev->hard_header_cache && !dst->hh) { + write_lock_bh(&neigh->lock); + if (!dst->hh) + neigh_hh_init(neigh, dst, dst->ops->protocol); + err = dev->hard_header(skb, dev, ntohs(skb->protocol), + neigh->ha, NULL, skb->len); + write_unlock_bh(&neigh->lock); + } else { + read_lock_bh(&neigh->lock); + err = dev->hard_header(skb, dev, ntohs(skb->protocol), + neigh->ha, NULL, skb->len); + 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; +} + +/* As fast as possible without hh cache */ + +int neigh_connected_output(struct sk_buff *skb) +{ + int err; + struct dst_entry *dst = skb->dst; + struct neighbour *neigh = dst->neighbour; + struct net_device *dev = neigh->dev; + + __skb_pull(skb, skb->nh.raw - skb->data); + + read_lock_bh(&neigh->lock); + err = dev->hard_header(skb, dev, ntohs(skb->protocol), + neigh->ha, NULL, skb->len); + read_unlock_bh(&neigh->lock); + if (err >= 0) + err = neigh->ops->queue_xmit(skb); + else { + err = -EINVAL; + kfree_skb(skb); + } + return err; +} + +static void neigh_proxy_process(unsigned long arg) +{ + struct neigh_table *tbl = (struct neigh_table *)arg; + long sched_next = 0; + unsigned long now = jiffies; + struct sk_buff *skb; + + spin_lock(&tbl->proxy_queue.lock); + + skb = tbl->proxy_queue.next; + + while (skb != (struct sk_buff *)&tbl->proxy_queue) { + struct sk_buff *back = skb; + long tdif = back->stamp.tv_usec - now; + + skb = skb->next; + if (tdif <= 0) { + struct net_device *dev = back->dev; + __skb_unlink(back, &tbl->proxy_queue); + if (tbl->proxy_redo && netif_running(dev)) + tbl->proxy_redo(back); + else + kfree_skb(back); + + 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; + } + skb->stamp.tv_sec = LOCALLY_ENQUEUED; + skb->stamp.tv_usec = sched_next; + + 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; + } + dst_release(skb->dst); + skb->dst = NULL; + dev_hold(skb->dev); + __skb_queue_tail(&tbl->proxy_queue, skb); + mod_timer(&tbl->proxy_timer, sched_next); + spin_unlock(&tbl->proxy_queue.lock); +} + + +struct neigh_parms *neigh_parms_alloc(struct net_device *dev, + struct neigh_table *tbl) +{ + struct neigh_parms *p = kmalloc(sizeof(*p), GFP_KERNEL); + + if (p) { + memcpy(p, &tbl->parms, sizeof(*p)); + p->tbl = tbl; + atomic_set(&p->refcnt, 1); + INIT_RCU_HEAD(&p->rcu_head); + p->reachable_time = + neigh_rand_reach_time(p->base_reachable_time); + if (dev && dev->neigh_setup && dev->neigh_setup(dev, p)) { + kfree(p); + return NULL; + } + 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; +} + +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); + call_rcu(&parms->rcu_head, neigh_rcu_free_parms); + return; + } + } + write_unlock_bh(&tbl->lock); + NEIGH_PRINTK1("neigh_parms_release: not found\n"); +} + +void neigh_parms_destroy(struct neigh_parms *parms) +{ + kfree(parms); +} + + +void neigh_table_init(struct neigh_table *tbl) +{ + unsigned long now = jiffies; + unsigned long phsize; + + atomic_set(&tbl->parms.refcnt, 1); + INIT_RCU_HEAD(&tbl->parms.rcu_head); + tbl->parms.reachable_time = + neigh_rand_reach_time(tbl->parms.base_reachable_time); + + if (!tbl->kmem_cachep) + tbl->kmem_cachep = kmem_cache_create(tbl->id, + tbl->entry_size, + 0, SLAB_HWCACHE_ALIGN, + NULL, NULL); + + if (!tbl->kmem_cachep) + panic("cannot create neighbour cache"); + + tbl->stats = alloc_percpu(struct neigh_statistics); + if (!tbl->stats) + panic("cannot create neighbour cache statistics"); + +#ifdef CONFIG_PROC_FS + tbl->pde = create_proc_entry(tbl->id, 0, proc_net_stat); + if (!tbl->pde) + panic("cannot create neighbour proc dir entry"); + tbl->pde->proc_fops = &neigh_stat_seq_fops; + tbl->pde->data = tbl; +#endif + + tbl->hash_mask = 1; + tbl->hash_buckets = neigh_hash_alloc(tbl->hash_mask + 1); + + phsize = (PNEIGH_HASHMASK + 1) * sizeof(struct pneigh_entry *); + tbl->phash_buckets = kmalloc(phsize, GFP_KERNEL); + + if (!tbl->hash_buckets || !tbl->phash_buckets) + panic("cannot allocate neighbour cache hashes"); + + memset(tbl->phash_buckets, 0, phsize); + + get_random_bytes(&tbl->hash_rnd, sizeof(tbl->hash_rnd)); + + rwlock_init(&tbl->lock); + init_timer(&tbl->gc_timer); + tbl->gc_timer.data = (unsigned long)tbl; + tbl->gc_timer.function = neigh_periodic_timer; + tbl->gc_timer.expires = now + 1; + add_timer(&tbl->gc_timer); + + init_timer(&tbl->proxy_timer); + tbl->proxy_timer.data = (unsigned long)tbl; + tbl->proxy_timer.function = neigh_proxy_process; + skb_queue_head_init(&tbl->proxy_queue); + + tbl->last_flush = now; + tbl->last_rand = now + tbl->parms.reachable_time * 20; + write_lock(&neigh_tbl_lock); + tbl->next = neigh_tables; + neigh_tables = tbl; + write_unlock(&neigh_tbl_lock); +} + +int neigh_table_clear(struct neigh_table *tbl) +{ + struct neigh_table **tp; + + /* It is not clean... Fix it to unload IPv6 module safely */ + del_timer_sync(&tbl->gc_timer); + 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; + + return 0; +} + +int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) +{ + struct ndmsg *ndm = NLMSG_DATA(nlh); + struct rtattr **nda = arg; + struct neigh_table *tbl; + struct net_device *dev = NULL; + int err = -ENODEV; + + if (ndm->ndm_ifindex && + (dev = dev_get_by_index(ndm->ndm_ifindex)) == NULL) + goto out; + + read_lock(&neigh_tbl_lock); + for (tbl = neigh_tables; tbl; tbl = tbl->next) { + struct rtattr *dst_attr = nda[NDA_DST - 1]; + struct neighbour *n; + + if (tbl->family != ndm->ndm_family) + continue; + read_unlock(&neigh_tbl_lock); + + err = -EINVAL; + if (!dst_attr || RTA_PAYLOAD(dst_attr) < tbl->key_len) + goto out_dev_put; + + if (ndm->ndm_flags & NTF_PROXY) { + err = pneigh_delete(tbl, RTA_DATA(dst_attr), dev); + goto out_dev_put; + } + + if (!dev) + goto out; + + n = neigh_lookup(tbl, RTA_DATA(dst_attr), dev); + if (n) { + err = neigh_update(n, NULL, NUD_FAILED, + NEIGH_UPDATE_F_OVERRIDE| + NEIGH_UPDATE_F_ADMIN); + neigh_release(n); + } + goto out_dev_put; + } + read_unlock(&neigh_tbl_lock); + err = -EADDRNOTAVAIL; +out_dev_put: + if (dev) + dev_put(dev); +out: + return err; +} + +int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) +{ + struct ndmsg *ndm = NLMSG_DATA(nlh); + struct rtattr **nda = arg; + struct neigh_table *tbl; + struct net_device *dev = NULL; + int err = -ENODEV; + + if (ndm->ndm_ifindex && + (dev = dev_get_by_index(ndm->ndm_ifindex)) == NULL) + goto out; + + read_lock(&neigh_tbl_lock); + for (tbl = neigh_tables; tbl; tbl = tbl->next) { + struct rtattr *lladdr_attr = nda[NDA_LLADDR - 1]; + struct rtattr *dst_attr = nda[NDA_DST - 1]; + int override = 1; + struct neighbour *n; + + if (tbl->family != ndm->ndm_family) + continue; + read_unlock(&neigh_tbl_lock); + + err = -EINVAL; + if (!dst_attr || RTA_PAYLOAD(dst_attr) < tbl->key_len) + goto out_dev_put; + + if (ndm->ndm_flags & NTF_PROXY) { + err = -ENOBUFS; + if (pneigh_lookup(tbl, RTA_DATA(dst_attr), dev, 1)) + err = 0; + goto out_dev_put; + } + + err = -EINVAL; + if (!dev) + goto out; + if (lladdr_attr && RTA_PAYLOAD(lladdr_attr) < dev->addr_len) + goto out_dev_put; + + n = neigh_lookup(tbl, RTA_DATA(dst_attr), dev); + if (n) { + if (nlh->nlmsg_flags & NLM_F_EXCL) { + err = -EEXIST; + neigh_release(n); + goto out_dev_put; + } + + override = nlh->nlmsg_flags & NLM_F_REPLACE; + } else if (!(nlh->nlmsg_flags & NLM_F_CREATE)) { + err = -ENOENT; + goto out_dev_put; + } else { + n = __neigh_lookup_errno(tbl, RTA_DATA(dst_attr), dev); + if (IS_ERR(n)) { + err = PTR_ERR(n); + goto out_dev_put; + } + } + + err = neigh_update(n, + lladdr_attr ? RTA_DATA(lladdr_attr) : NULL, + ndm->ndm_state, + (override ? NEIGH_UPDATE_F_OVERRIDE : 0) | + NEIGH_UPDATE_F_ADMIN); + + neigh_release(n); + goto out_dev_put; + } + + read_unlock(&neigh_tbl_lock); + err = -EADDRNOTAVAIL; +out_dev_put: + if (dev) + dev_put(dev); +out: + return err; +} + + +static int neigh_fill_info(struct sk_buff *skb, struct neighbour *n, + u32 pid, u32 seq, int event) +{ + unsigned long now = jiffies; + unsigned char *b = skb->tail; + struct nda_cacheinfo ci; + int locked = 0; + u32 probes; + struct nlmsghdr *nlh = NLMSG_PUT(skb, pid, seq, event, + sizeof(struct ndmsg)); + struct ndmsg *ndm = NLMSG_DATA(nlh); + + nlh->nlmsg_flags = pid ? NLM_F_MULTI : 0; + ndm->ndm_family = n->ops->family; + ndm->ndm_flags = n->flags; + ndm->ndm_type = n->type; + ndm->ndm_ifindex = n->dev->ifindex; + RTA_PUT(skb, NDA_DST, n->tbl->key_len, n->primary_key); + read_lock_bh(&n->lock); + locked = 1; + ndm->ndm_state = n->nud_state; + if (n->nud_state & NUD_VALID) + RTA_PUT(skb, NDA_LLADDR, n->dev->addr_len, n->ha); + ci.ndm_used = now - n->used; + ci.ndm_confirmed = now - n->confirmed; + ci.ndm_updated = now - n->updated; + ci.ndm_refcnt = atomic_read(&n->refcnt) - 1; + probes = atomic_read(&n->probes); + read_unlock_bh(&n->lock); + locked = 0; + RTA_PUT(skb, NDA_CACHEINFO, sizeof(ci), &ci); + RTA_PUT(skb, NDA_PROBES, sizeof(probes), &probes); + nlh->nlmsg_len = skb->tail - b; + return skb->len; + +nlmsg_failure: +rtattr_failure: + if (locked) + read_unlock_bh(&n->lock); + skb_trim(skb, b - skb->data); + return -1; +} + + +static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb, + struct netlink_callback *cb) +{ + struct neighbour *n; + int rc, h, s_h = cb->args[1]; + int idx, s_idx = idx = cb->args[2]; + + for (h = 0; h <= tbl->hash_mask; h++) { + if (h < s_h) + continue; + if (h > s_h) + s_idx = 0; + read_lock_bh(&tbl->lock); + for (n = tbl->hash_buckets[h], idx = 0; n; n = n->next, idx++) { + if (idx < s_idx) + continue; + if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).pid, + cb->nlh->nlmsg_seq, + RTM_NEWNEIGH) <= 0) { + read_unlock_bh(&tbl->lock); + rc = -1; + goto out; + } + } + read_unlock_bh(&tbl->lock); + } + rc = skb->len; +out: + cb->args[1] = h; + cb->args[2] = idx; + return rc; +} + +int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb) +{ + struct neigh_table *tbl; + int t, family, s_t; + + read_lock(&neigh_tbl_lock); + family = ((struct rtgenmsg *)NLMSG_DATA(cb->nlh))->rtgen_family; + 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); + if (release) + neigh_release(n); + } + } +} +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; + 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) { + 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; + 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) { + 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) { + 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 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]; + 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 neigh_table *tbl = state->tbl; + + pn = pn->next; + while (!pn) { + if (++state->bucket > PNEIGH_HASHMASK) + break; + pn = tbl->phash_buckets[state->bucket]; + 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) { + 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; + + rc = neigh_get_idx(seq, pos); + if (!rc && !(state->flags & NEIGH_SEQ_NEIGH_ONLY)) + rc = pneigh_get_idx(seq, pos); + + return rc; +} + +void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags) +{ + struct neigh_seq_state *state = seq->private; + loff_t pos_minus_one; + + state->tbl = tbl; + state->bucket = 0; + state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH); + + read_lock_bh(&tbl->lock); + + pos_minus_one = *pos - 1; + return *pos ? neigh_get_idx_any(seq, &pos_minus_one) : 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_idx(seq, pos); + 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) +{ + 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) +{ + struct proc_dir_entry *pde = seq->private; + struct neigh_table *tbl = pde->data; + int cpu; + + if (*pos == 0) + return SEQ_START_TOKEN; + + for (cpu = *pos-1; cpu < NR_CPUS; ++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 proc_dir_entry *pde = seq->private; + struct neigh_table *tbl = pde->data; + int cpu; + + for (cpu = *pos; cpu < NR_CPUS; ++cpu) { + 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) +{ + struct proc_dir_entry *pde = seq->private; + struct neigh_table *tbl = pde->data; + struct neigh_statistics *st = v; + + if (v == SEQ_START_TOKEN) { + seq_printf(seq, "entries allocs destroys hash_grows lookups hits res_failed rcv_probes_mcast rcv_probes_ucast periodic_gc_runs forced_gc_runs forced_gc_goal_miss\n"); + return 0; + } + + seq_printf(seq, "%08x %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 + ); + + return 0; +} + +static 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, +}; + +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; + sf->private = PDE(inode); + } + return ret; +}; + +static struct file_operations neigh_stat_seq_fops = { + .owner = THIS_MODULE, + .open = neigh_stat_seq_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +#endif /* CONFIG_PROC_FS */ + +#ifdef CONFIG_ARPD +void neigh_app_ns(struct neighbour *n) +{ + struct nlmsghdr *nlh; + int size = NLMSG_SPACE(sizeof(struct ndmsg) + 256); + struct sk_buff *skb = alloc_skb(size, GFP_ATOMIC); + + if (!skb) + return; + + if (neigh_fill_info(skb, n, 0, 0, RTM_GETNEIGH) < 0) { + kfree_skb(skb); + return; + } + nlh = (struct nlmsghdr *)skb->data; + nlh->nlmsg_flags = NLM_F_REQUEST; + NETLINK_CB(skb).dst_groups = RTMGRP_NEIGH; + netlink_broadcast(rtnl, skb, 0, RTMGRP_NEIGH, GFP_ATOMIC); +} + +static void neigh_app_notify(struct neighbour *n) +{ + struct nlmsghdr *nlh; + int size = NLMSG_SPACE(sizeof(struct ndmsg) + 256); + struct sk_buff *skb = alloc_skb(size, GFP_ATOMIC); + + if (!skb) + return; + + if (neigh_fill_info(skb, n, 0, 0, RTM_NEWNEIGH) < 0) { + kfree_skb(skb); + return; + } + nlh = (struct nlmsghdr *)skb->data; + NETLINK_CB(skb).dst_groups = RTMGRP_NEIGH; + netlink_broadcast(rtnl, skb, 0, RTMGRP_NEIGH, GFP_ATOMIC); +} + +#endif /* CONFIG_ARPD */ + +#ifdef CONFIG_SYSCTL + +static struct neigh_sysctl_table { + struct ctl_table_header *sysctl_header; + ctl_table neigh_vars[__NET_NEIGH_MAX]; + ctl_table neigh_dev[2]; + ctl_table neigh_neigh_dir[2]; + ctl_table neigh_proto_dir[2]; + ctl_table neigh_root_dir[2]; +} neigh_sysctl_template = { + .neigh_vars = { + { + .ctl_name = NET_NEIGH_MCAST_SOLICIT, + .procname = "mcast_solicit", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { + .ctl_name = NET_NEIGH_UCAST_SOLICIT, + .procname = "ucast_solicit", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { + .ctl_name = NET_NEIGH_APP_SOLICIT, + .procname = "app_solicit", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { + .ctl_name = NET_NEIGH_RETRANS_TIME, + .procname = "retrans_time", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec_userhz_jiffies, + }, + { + .ctl_name = NET_NEIGH_REACHABLE_TIME, + .procname = "base_reachable_time", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec_jiffies, + .strategy = &sysctl_jiffies, + }, + { + .ctl_name = NET_NEIGH_DELAY_PROBE_TIME, + .procname = "delay_first_probe_time", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec_jiffies, + .strategy = &sysctl_jiffies, + }, + { + .ctl_name = NET_NEIGH_GC_STALE_TIME, + .procname = "gc_stale_time", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec_jiffies, + .strategy = &sysctl_jiffies, + }, + { + .ctl_name = NET_NEIGH_UNRES_QLEN, + .procname = "unres_qlen", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { + .ctl_name = NET_NEIGH_PROXY_QLEN, + .procname = "proxy_qlen", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { + .ctl_name = NET_NEIGH_ANYCAST_DELAY, + .procname = "anycast_delay", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec_userhz_jiffies, + }, + { + .ctl_name = NET_NEIGH_PROXY_DELAY, + .procname = "proxy_delay", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec_userhz_jiffies, + }, + { + .ctl_name = NET_NEIGH_LOCKTIME, + .procname = "locktime", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec_userhz_jiffies, + }, + { + .ctl_name = NET_NEIGH_GC_INTERVAL, + .procname = "gc_interval", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec_jiffies, + .strategy = &sysctl_jiffies, + }, + { + .ctl_name = NET_NEIGH_GC_THRESH1, + .procname = "gc_thresh1", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { + .ctl_name = NET_NEIGH_GC_THRESH2, + .procname = "gc_thresh2", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { + .ctl_name = NET_NEIGH_GC_THRESH3, + .procname = "gc_thresh3", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { + .ctl_name = NET_NEIGH_RETRANS_TIME_MS, + .procname = "retrans_time_ms", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec_ms_jiffies, + .strategy = &sysctl_ms_jiffies, + }, + { + .ctl_name = NET_NEIGH_REACHABLE_TIME_MS, + .procname = "base_reachable_time_ms", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec_ms_jiffies, + .strategy = &sysctl_ms_jiffies, + }, + }, + .neigh_dev = { + { + .ctl_name = NET_PROTO_CONF_DEFAULT, + .procname = "default", + .mode = 0555, + }, + }, + .neigh_neigh_dir = { + { + .procname = "neigh", + .mode = 0555, + }, + }, + .neigh_proto_dir = { + { + .mode = 0555, + }, + }, + .neigh_root_dir = { + { + .ctl_name = CTL_NET, + .procname = "net", + .mode = 0555, + }, + }, +}; + +int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p, + int p_id, int pdev_id, char *p_name, + proc_handler *handler, ctl_handler *strategy) +{ + struct neigh_sysctl_table *t = kmalloc(sizeof(*t), GFP_KERNEL); + const char *dev_name_source = NULL; + char *dev_name = NULL; + int err = 0; + + if (!t) + return -ENOBUFS; + memcpy(t, &neigh_sysctl_template, sizeof(*t)); + 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; + + if (dev) { + dev_name_source = dev->name; + t->neigh_dev[0].ctl_name = dev->ifindex; + t->neigh_vars[12].procname = NULL; + t->neigh_vars[13].procname = NULL; + t->neigh_vars[14].procname = NULL; + t->neigh_vars[15].procname = NULL; + } else { + dev_name_source = t->neigh_dev[0].procname; + t->neigh_vars[12].data = (int *)(p + 1); + t->neigh_vars[13].data = (int *)(p + 1) + 1; + t->neigh_vars[14].data = (int *)(p + 1) + 2; + t->neigh_vars[15].data = (int *)(p + 1) + 3; + } + + t->neigh_vars[16].data = &p->retrans_time; + t->neigh_vars[17].data = &p->base_reachable_time; + + if (handler || strategy) { + /* RetransTime */ + t->neigh_vars[3].proc_handler = handler; + t->neigh_vars[3].strategy = strategy; + t->neigh_vars[3].extra1 = dev; + /* ReachableTime */ + t->neigh_vars[4].proc_handler = handler; + t->neigh_vars[4].strategy = strategy; + t->neigh_vars[4].extra1 = dev; + /* RetransTime (in milliseconds)*/ + t->neigh_vars[16].proc_handler = handler; + t->neigh_vars[16].strategy = strategy; + t->neigh_vars[16].extra1 = dev; + /* ReachableTime (in milliseconds) */ + t->neigh_vars[17].proc_handler = handler; + t->neigh_vars[17].strategy = strategy; + t->neigh_vars[17].extra1 = dev; + } + + dev_name = net_sysctl_strdup(dev_name_source); + if (!dev_name) { + err = -ENOBUFS; + goto free; + } + + t->neigh_dev[0].procname = dev_name; + + t->neigh_neigh_dir[0].ctl_name = pdev_id; + + t->neigh_proto_dir[0].procname = p_name; + t->neigh_proto_dir[0].ctl_name = p_id; + + t->neigh_dev[0].child = t->neigh_vars; + t->neigh_neigh_dir[0].child = t->neigh_dev; + t->neigh_proto_dir[0].child = t->neigh_neigh_dir; + t->neigh_root_dir[0].child = t->neigh_proto_dir; + + t->sysctl_header = register_sysctl_table(t->neigh_root_dir, 0); + if (!t->sysctl_header) { + err = -ENOBUFS; + goto free_procname; + } + p->sysctl_table = t; + return 0; + + /* error path */ + free_procname: + kfree(dev_name); + free: + kfree(t); + + return err; +} + +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); + kfree(t->neigh_dev[0].procname); + kfree(t); + } +} + +#endif /* CONFIG_SYSCTL */ + +EXPORT_SYMBOL(__neigh_event_send); +EXPORT_SYMBOL(neigh_add); +EXPORT_SYMBOL(neigh_changeaddr); +EXPORT_SYMBOL(neigh_compat_output); +EXPORT_SYMBOL(neigh_connected_output); +EXPORT_SYMBOL(neigh_create); +EXPORT_SYMBOL(neigh_delete); +EXPORT_SYMBOL(neigh_destroy); +EXPORT_SYMBOL(neigh_dump_info); +EXPORT_SYMBOL(neigh_event_ns); +EXPORT_SYMBOL(neigh_ifdown); +EXPORT_SYMBOL(neigh_lookup); +EXPORT_SYMBOL(neigh_lookup_nodev); +EXPORT_SYMBOL(neigh_parms_alloc); +EXPORT_SYMBOL(neigh_parms_release); +EXPORT_SYMBOL(neigh_rand_reach_time); +EXPORT_SYMBOL(neigh_resolve_output); +EXPORT_SYMBOL(neigh_table_clear); +EXPORT_SYMBOL(neigh_table_init); +EXPORT_SYMBOL(neigh_update); +EXPORT_SYMBOL(neigh_update_hhs); +EXPORT_SYMBOL(pneigh_enqueue); +EXPORT_SYMBOL(pneigh_lookup); + +#ifdef CONFIG_ARPD +EXPORT_SYMBOL(neigh_app_ns); +#endif +#ifdef CONFIG_SYSCTL +EXPORT_SYMBOL(neigh_sysctl_register); +EXPORT_SYMBOL(neigh_sysctl_unregister); +#endif |
