| // 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/kmemleak.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 |
| |
| /* |
| 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 ? (prandom_u32() % 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; |
| } |
| } |
| |
| static bool neigh_del(struct neighbour *n, struct neighbour __rcu **np, |
| struct neigh_table *tbl) |
| { |
| bool retval = false; |
| |
| write_lock(&n->lock); |
| if (refcount_read(&n->refcnt) == 1) { |
| struct neighbour *neigh; |
| |
| neigh = rcu_dereference_protected(n->next, |
| lockdep_is_held(&tbl->lock)); |
| rcu_assign_pointer(*np, neigh); |
| neigh_mark_dead(n); |
| retval = true; |
| } |
| write_unlock(&n->lock); |
| if (retval) |
| neigh_cleanup_and_release(n); |
| return retval; |
| } |
| |
| bool neigh_remove_one(struct neighbour *ndel, struct neigh_table *tbl) |
| { |
| struct neigh_hash_table *nht; |
| void *pkey = ndel->primary_key; |
| u32 hash_val; |
| struct neighbour *n; |
| struct neighbour __rcu **np; |
| |
| nht = rcu_dereference_protected(tbl->nht, |
| lockdep_is_held(&tbl->lock)); |
| hash_val = tbl->hash(pkey, ndel->dev, nht->hash_rnd); |
| hash_val = hash_val >> (32 - nht->hash_shift); |
| |
| np = &nht->hash_buckets[hash_val]; |
| while ((n = rcu_dereference_protected(*np, |
| lockdep_is_held(&tbl->lock)))) { |
| if (n == ndel) |
| return neigh_del(n, np, tbl); |
| np = &n->next; |
| } |
| return false; |
| } |
| |
| static int neigh_forced_gc(struct neigh_table *tbl) |
| { |
| int max_clean = atomic_read(&tbl->gc_entries) - tbl->gc_thresh2; |
| unsigned long tref = jiffies - 5 * HZ; |
| struct neighbour *n, *tmp; |
| int shrunk = 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_after(tref, n->updated)) |
| remove = true; |
| write_unlock(&n->lock); |
| |
| if (remove && neigh_remove_one(n, tbl)) |
| shrunk++; |
| if (shrunk >= max_clean) |
| break; |
| } |
| } |
| |
| tbl->last_flush = jiffies; |
| |
| write_unlock_bh(&tbl->lock); |
| |
| return shrunk; |
| } |
| |
| static void neigh_add_timer(struct neighbour *n, unsigned long when) |
| { |
| neigh_hold(n); |
| if (unlikely(mod_timer(&n->timer, when))) { |
| printk("NEIGH: BUG, double timer add, state is %x\n", |
| n->nud_state); |
| dump_stack(); |
| } |
| } |
| |
| 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); |
| } |
| } |
| |
| static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev, |
| bool skip_perm) |
| { |
| int i; |
| struct neigh_hash_table *nht; |
| |
| nht = rcu_dereference_protected(tbl->nht, |
| lockdep_is_held(&tbl->lock)); |
| |
| for (i = 0; i < (1 << nht->hash_shift); i++) { |
| struct neighbour *n; |
| struct neighbour __rcu **np = &nht->hash_buckets[i]; |
| |
| while ((n = rcu_dereference_protected(*np, |
| lockdep_is_held(&tbl->lock))) != NULL) { |
| if (dev && n->dev != dev) { |
| np = &n->next; |
| continue; |
| } |
| if (skip_perm && n->nud_state & NUD_PERMANENT) { |
| np = &n->next; |
| continue; |
| } |
| rcu_assign_pointer(*np, |
| rcu_dereference_protected(n->next, |
| lockdep_is_held(&tbl->lock))); |
| 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; |
| 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); |
| |
| del_timer_sync(&tbl->proxy_timer); |
| pneigh_queue_purge(&tbl->proxy_queue); |
| 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; |
| |
| if (exempt_from_gc) |
| goto do_alloc; |
| |
| entries = atomic_inc_return(&tbl->gc_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) { |
| 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 neighbour *); |
| struct neigh_hash_table *ret; |
| struct neighbour __rcu **buckets; |
| int i; |
| |
| ret = kmalloc(sizeof(*ret), GFP_ATOMIC); |
| if (!ret) |
| return NULL; |
| if (size <= PAGE_SIZE) { |
| buckets = kzalloc(size, GFP_ATOMIC); |
| } else { |
| buckets = (struct neighbour __rcu **) |
| __get_free_pages(GFP_ATOMIC | __GFP_ZERO, |
| get_order(size)); |
| kmemleak_alloc(buckets, size, 1, GFP_ATOMIC); |
| } |
| if (!buckets) { |
| kfree(ret); |
| return NULL; |
| } |
| ret->hash_buckets = buckets; |
| 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); |
| size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *); |
| struct neighbour __rcu **buckets = nht->hash_buckets; |
| |
| if (size <= PAGE_SIZE) { |
| kfree(buckets); |
| } else { |
| kmemleak_free(buckets); |
| free_pages((unsigned long)buckets, get_order(size)); |
| } |
| 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 neighbour *n, *next; |
| |
| for (n = rcu_dereference_protected(old_nht->hash_buckets[i], |
| lockdep_is_held(&tbl->lock)); |
| n != NULL; |
| n = next) { |
| hash = tbl->hash(n->primary_key, n->dev, |
| new_nht->hash_rnd); |
| |
| hash >>= (32 - new_nht->hash_shift); |
| next = rcu_dereference_protected(n->next, |
| lockdep_is_held(&tbl->lock)); |
| |
| rcu_assign_pointer(n->next, |
| rcu_dereference_protected( |
| new_nht->hash_buckets[hash], |
| lockdep_is_held(&tbl->lock))); |
| rcu_assign_pointer(new_nht->hash_buckets[hash], n); |
| } |
| } |
| |
| 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_bh(); |
| 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_bh(); |
| return n; |
| } |
| EXPORT_SYMBOL(neigh_lookup); |
| |
| struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net, |
| const void *pkey) |
| { |
| struct neighbour *n; |
| unsigned int key_len = tbl->key_len; |
| u32 hash_val; |
| struct neigh_hash_table *nht; |
| |
| NEIGH_CACHE_STAT_INC(tbl, lookups); |
| |
| rcu_read_lock_bh(); |
| nht = rcu_dereference_bh(tbl->nht); |
| hash_val = tbl->hash(pkey, NULL, nht->hash_rnd) >> (32 - nht->hash_shift); |
| |
| for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]); |
| n != NULL; |
| n = rcu_dereference_bh(n->next)) { |
| if (!memcmp(n->primary_key, pkey, key_len) && |
| net_eq(dev_net(n->dev), net)) { |
| if (!refcount_inc_not_zero(&n->refcnt)) |
| n = NULL; |
| NEIGH_CACHE_STAT_INC(tbl, hits); |
| break; |
| } |
| } |
| |
| rcu_read_unlock_bh(); |
| return n; |
| } |
| EXPORT_SYMBOL(neigh_lookup_nodev); |
| |
| 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; |
| dev_hold_track(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; |
| } |
| |
| for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val], |
| lockdep_is_held(&tbl->lock)); |
| n1 != NULL; |
| n1 = rcu_dereference_protected(n1->next, |
| lockdep_is_held(&tbl->lock))) { |
| 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); |
| rcu_assign_pointer(n->next, |
| rcu_dereference_protected(nht->hash_buckets[hash_val], |
| lockdep_is_held(&tbl->lock))); |
| rcu_assign_pointer(nht->hash_buckets[hash_val], n); |
| 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) |
| { |
| return ___neigh_create(tbl, pkey, dev, 0, false, 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; |
| dev_hold_track(dev, &n->dev_tracker, GFP_KERNEL); |
| |
| if (tbl->pconstructor && tbl->pconstructor(n)) { |
| dev_put_track(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); |
| dev_put_track(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); |
| dev_put_track(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); |
| |
| dev_put_track(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); |
| |
| 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); |
| |
| 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 neighbour *n; |
| struct neighbour __rcu **np; |
| unsigned int i; |
| struct neigh_hash_table *nht; |
| |
| 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; |
| 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) < tbl->gc_thresh1) |
| goto out; |
| |
| for (i = 0 ; i < (1 << nht->hash_shift); i++) { |
| np = &nht->hash_buckets[i]; |
| |
| while ((n = rcu_dereference_protected(*np, |
| lockdep_is_held(&tbl->lock))) != NULL) { |
| 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); |
| goto next_elt; |
| } |
| |
| if (time_before(n->used, n->confirmed)) |
| n->used = n->confirmed; |
| |
| if (refcount_read(&n->refcnt) == 1 && |
| (state == NUD_FAILED || |
| time_after(jiffies, n->used + NEIGH_VAR(n->parms, GC_STALETIME)))) { |
| *np = n->next; |
| neigh_mark_dead(n); |
| write_unlock(&n->lock); |
| neigh_cleanup_and_release(n); |
| continue; |
| } |
| write_unlock(&n->lock); |
| |
| next_elt: |
| np = &n->next; |
| } |
| /* |
| * It's fine to release lock here, even if hash table |
| * grows while we are preempted. |
| */ |
| write_unlock_bh(&tbl->lock); |
| cond_resched(); |
| write_lock_bh(&tbl->lock); |
| 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); |
| 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); |
| 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); |
| 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); |
| 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)) { |
| 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); |
| 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 { |
| 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); |
| 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, ¬ify, &gc_update, &managed_update); |
| if (flags & (NEIGH_UPDATE_F_USE | NEIGH_UPDATE_F_MANAGED)) { |
| new = old & ~NUD_PERMANENT; |
| neigh->nud_state = new; |
| err = 0; |
| goto out; |
| } |
| |
| if (!(new & NUD_VALID)) { |
| neigh_del_timer(neigh); |
| if (old & NUD_CONNECTED) |
| neigh_suspect(neigh); |
| neigh->nud_state = new; |
| err = 0; |
| notify = old & NUD_VALID; |
| 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))); |
| 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; |
| } |
| 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, ¬ify); |
| 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; |
| 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, |
| max(NEIGH_VAR(&tbl->parms, DELAY_PROBE_TIME), HZ)); |
| 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; |
| |
| __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); |
| } |
| |
| void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p, |
| struct sk_buff *skb) |
| { |
| unsigned long sched_next = jiffies + |
| prandom_u32_max(NEIGH_VAR(p, PROXY_DELAY)); |
| |
| if (tbl->proxy_queue.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); |
| 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)); |
| dev_hold_track(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)) { |
| dev_put_track(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); |
| dev_put_track(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 *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->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; |
| |
| neigh_tables[index] = tbl; |
| } |
| EXPORT_SYMBOL(neigh_table_init); |
| |
| int neigh_table_clear(int index, struct neigh_table *tbl) |
| { |
| neigh_tables[index] = NULL; |
| /* 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); |
| 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 = neigh_tables[NEIGH_ARP_TABLE]; |
| break; |
| case AF_INET6: |
| tbl = neigh_tables[NEIGH_ND_TABLE]; |
| break; |
| case AF_DECnet: |
| tbl = neigh_tables[NEIGH_DN_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, tbl); |
| 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)) |
| 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, tbl->gc_interval, NDTA_PAD) || |
| nla_put_u32(skb, NDTA_THRESH1, tbl->gc_thresh1) || |
| nla_put_u32(skb, NDTA_THRESH2, tbl->gc_thresh2) || |
| nla_put_u32(skb, NDTA_THRESH3, tbl->gc_thresh3)) |
| goto nla_put_failure; |
| { |
| unsigned long now = jiffies; |
| long flush_delta = now - tbl->last_flush; |
| long rand_delta = now - 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 = tbl->proxy_queue.qlen, |
| }; |
| |
| rcu_read_lock_bh(); |
| nht = rcu_dereference_bh(tbl->nht); |
| ndc.ndtc_hash_rnd = nht->hash_rnd[0]; |
| ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1); |
| rcu_read_unlock_bh(); |
| |
| 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 += st->allocs; |
| ndst.ndts_destroys += st->destroys; |
| ndst.ndts_hash_grows += st->hash_grows; |
| ndst.ndts_res_failed += st->res_failed; |
| ndst.ndts_lookups += st->lookups; |
| ndst.ndts_hits += st->hits; |
| ndst.ndts_rcv_probes_mcast += st->rcv_probes_mcast; |
| ndst.ndts_rcv_probes_ucast += st->rcv_probes_ucast; |
| ndst.ndts_periodic_gc_runs += st->periodic_gc_runs; |
| ndst.ndts_forced_gc_runs += st->forced_gc_runs; |
| ndst.ndts_table_fulls += 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 }, |
| }; |
| |
| 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 = 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_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]) |
| tbl->gc_thresh1 = nla_get_u32(tb[NDTA_THRESH1]); |
| |
| if (tb[NDTA_THRESH2]) |
| tbl->gc_thresh2 = nla_get_u32(tb[NDTA_THRESH2]); |
| |
| if (tb[NDTA_THRESH3]) |
| tbl->gc_thresh3 = nla_get_u32(tb[NDTA_THRESH3]); |
| |
| if (tb[NDTA_GC_INTERVAL]) |
| 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 = 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(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 rc, 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; |
| |
| rcu_read_lock_bh(); |
| nht = rcu_dereference_bh(tbl->nht); |
| |
| for (h = s_h; h < (1 << nht->hash_shift); h++) { |
| if (h > s_h) |
| s_idx = 0; |
| for (n = rcu_dereference_bh(nht->hash_buckets[h]), idx = 0; |
| n != NULL; |
| n = rcu_dereference_bh(n->next)) { |
| 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; |
| if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid, |
| cb->nlh->nlmsg_seq, |
| RTM_NEWNEIGH, |
| flags) < 0) { |
| rc = -1; |
| goto out; |
| } |
| next: |
| idx++; |
| } |
| } |
| rc = skb->len; |
| out: |
| rcu_read_unlock_bh(); |
| cb->args[1] = h; |
| cb->args[2] = idx; |
| return rc; |
| } |
| |
| 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 rc, 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; |
| if (pneigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid, |
| cb->nlh->nlmsg_seq, |
| RTM_NEWNEIGH, flags, tbl) < 0) { |
| read_unlock_bh(&tbl->lock); |
| rc = -1; |
| goto out; |
| } |
| next: |
| idx++; |
| } |
| } |
| |
| read_unlock_bh(&tbl->lock); |
| rc = skb->len; |
| out: |
| cb->args[3] = h; |
| cb->args[4] = idx; |
| return rc; |
| |
| } |
| |
| 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]; |
| |
| for (t = 0; t < NEIGH_NR_TABLES; t++) { |
| tbl = 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; |
| } |
| |
| cb->args[0] = t; |
| return skb->len; |
| } |
| |
| 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; |
|