diff options
| -rw-r--r-- | include/net/netfilter/nf_nat.h | 4 | ||||
| -rw-r--r-- | net/netfilter/nf_nat_core.c | 157 |
2 files changed, 161 insertions, 0 deletions
diff --git a/include/net/netfilter/nf_nat.h b/include/net/netfilter/nf_nat.h index da3d601cadee..a17eb2f8d40e 100644 --- a/include/net/netfilter/nf_nat.h +++ b/include/net/netfilter/nf_nat.h @@ -75,4 +75,8 @@ static inline bool nf_nat_oif_changed(unsigned int hooknum, #endif } +int nf_nat_register_fn(struct net *net, const struct nf_hook_ops *ops, + const struct nf_hook_ops *nat_ops, unsigned int ops_count); +void nf_nat_unregister_fn(struct net *net, const struct nf_hook_ops *ops, + unsigned int ops_count); #endif diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c index 0cd503aacbf0..f531d77dd684 100644 --- a/net/netfilter/nf_nat_core.c +++ b/net/netfilter/nf_nat_core.c @@ -32,6 +32,8 @@ #include <net/netfilter/nf_conntrack_zones.h> #include <linux/netfilter/nf_nat.h> +#include "nf_internals.h" + static spinlock_t nf_nat_locks[CONNTRACK_LOCKS]; static DEFINE_MUTEX(nf_nat_proto_mutex); @@ -39,11 +41,27 @@ static const struct nf_nat_l3proto __rcu *nf_nat_l3protos[NFPROTO_NUMPROTO] __read_mostly; static const struct nf_nat_l4proto __rcu **nf_nat_l4protos[NFPROTO_NUMPROTO] __read_mostly; +static unsigned int nat_net_id __read_mostly; static struct hlist_head *nf_nat_bysource __read_mostly; static unsigned int nf_nat_htable_size __read_mostly; static unsigned int nf_nat_hash_rnd __read_mostly; +struct nf_nat_lookup_hook_priv { + struct nf_hook_entries __rcu *entries; + + struct rcu_head rcu_head; +}; + +struct nf_nat_hooks_net { + struct nf_hook_ops *nat_hook_ops; + unsigned int users; +}; + +struct nat_net { + struct nf_nat_hooks_net nat_proto_net[NFPROTO_NUMPROTO]; +}; + inline const struct nf_nat_l3proto * __nf_nat_l3proto_find(u8 family) { @@ -871,6 +889,138 @@ static struct nf_ct_helper_expectfn follow_master_nat = { .expectfn = nf_nat_follow_master, }; +int nf_nat_register_fn(struct net *net, const struct nf_hook_ops *ops, + const struct nf_hook_ops *orig_nat_ops, unsigned int ops_count) +{ + struct nat_net *nat_net = net_generic(net, nat_net_id); + struct nf_nat_hooks_net *nat_proto_net; + struct nf_nat_lookup_hook_priv *priv; + unsigned int hooknum = ops->hooknum; + struct nf_hook_ops *nat_ops; + int i, ret; + + if (WARN_ON_ONCE(ops->pf >= ARRAY_SIZE(nat_net->nat_proto_net))) + return -EINVAL; + + nat_proto_net = &nat_net->nat_proto_net[ops->pf]; + + for (i = 0; i < ops_count; i++) { + if (WARN_ON(orig_nat_ops[i].pf != ops->pf)) + return -EINVAL; + if (orig_nat_ops[i].hooknum == hooknum) { + hooknum = i; + break; + } + } + + if (WARN_ON_ONCE(i == ops_count)) + return -EINVAL; + + mutex_lock(&nf_nat_proto_mutex); + if (!nat_proto_net->nat_hook_ops) { + WARN_ON(nat_proto_net->users != 0); + + nat_ops = kmemdup(orig_nat_ops, sizeof(*orig_nat_ops) * ops_count, GFP_KERNEL); + if (!nat_ops) { + mutex_unlock(&nf_nat_proto_mutex); + return -ENOMEM; + } + + for (i = 0; i < ops_count; i++) { + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (priv) { + nat_ops[i].priv = priv; + continue; + } + mutex_unlock(&nf_nat_proto_mutex); + while (i) + kfree(nat_ops[--i].priv); + kfree(nat_ops); + return -ENOMEM; + } + + ret = nf_register_net_hooks(net, nat_ops, ops_count); + if (ret < 0) { + mutex_unlock(&nf_nat_proto_mutex); + for (i = 0; i < ops_count; i++) + kfree(nat_ops[i].priv); + kfree(nat_ops); + return ret; + } + + nat_proto_net->nat_hook_ops = nat_ops; + } + + nat_ops = nat_proto_net->nat_hook_ops; + priv = nat_ops[hooknum].priv; + if (WARN_ON_ONCE(!priv)) { + mutex_unlock(&nf_nat_proto_mutex); + return -EOPNOTSUPP; + } + + ret = nf_hook_entries_insert_raw(&priv->entries, ops); + if (ret == 0) + nat_proto_net->users++; + + mutex_unlock(&nf_nat_proto_mutex); + return ret; +} +EXPORT_SYMBOL_GPL(nf_nat_register_fn); + +void nf_nat_unregister_fn(struct net *net, const struct nf_hook_ops *ops, + unsigned int ops_count) +{ + struct nat_net *nat_net = net_generic(net, nat_net_id); + struct nf_nat_hooks_net *nat_proto_net; + struct nf_nat_lookup_hook_priv *priv; + struct nf_hook_ops *nat_ops; + int hooknum = ops->hooknum; + int i; + + if (ops->pf >= ARRAY_SIZE(nat_net->nat_proto_net)) + return; + + nat_proto_net = &nat_net->nat_proto_net[ops->pf]; + + mutex_lock(&nf_nat_proto_mutex); + if (WARN_ON(nat_proto_net->users == 0)) + goto unlock; + + nat_proto_net->users--; + + nat_ops = nat_proto_net->nat_hook_ops; + for (i = 0; i < ops_count; i++) { + if (nat_ops[i].hooknum == hooknum) { + hooknum = i; + break; + } + } + if (WARN_ON_ONCE(i == ops_count)) + goto unlock; + priv = nat_ops[hooknum].priv; + nf_hook_entries_delete_raw(&priv->entries, ops); + + if (nat_proto_net->users == 0) { + nf_unregister_net_hooks(net, nat_ops, ops_count); + + for (i = 0; i < ops_count; i++) { + priv = nat_ops[i].priv; + kfree_rcu(priv, rcu_head); + } + + nat_proto_net->nat_hook_ops = NULL; + kfree(nat_ops); + } +unlock: + mutex_unlock(&nf_nat_proto_mutex); +} +EXPORT_SYMBOL_GPL(nf_nat_unregister_fn); + +static struct pernet_operations nat_net_ops = { + .id = &nat_net_id, + .size = sizeof(struct nat_net), +}; + static int __init nf_nat_init(void) { int ret, i; @@ -894,6 +1044,12 @@ static int __init nf_nat_init(void) for (i = 0; i < CONNTRACK_LOCKS; i++) spin_lock_init(&nf_nat_locks[i]); + ret = register_pernet_subsys(&nat_net_ops); + if (ret < 0) { + nf_ct_extend_unregister(&nat_extend); + return ret; + } + nf_ct_helper_expectfn_register(&follow_master_nat); BUG_ON(nfnetlink_parse_nat_setup_hook != NULL); @@ -925,6 +1081,7 @@ static void __exit nf_nat_cleanup(void) kfree(nf_nat_l4protos[i]); synchronize_net(); nf_ct_free_hashtable(nf_nat_bysource, nf_nat_htable_size); + unregister_pernet_subsys(&nat_net_ops); } MODULE_LICENSE("GPL"); |