diff options
Diffstat (limited to 'kernel/net/netfilter/core.c')
-rw-r--r-- | kernel/net/netfilter/core.c | 233 |
1 files changed, 204 insertions, 29 deletions
diff --git a/kernel/net/netfilter/core.c b/kernel/net/netfilter/core.c index f0adf700b..10880c89d 100644 --- a/kernel/net/netfilter/core.c +++ b/kernel/net/netfilter/core.c @@ -40,6 +40,9 @@ EXPORT_SYMBOL(nf_afinfo); const struct nf_ipv6_ops __rcu *nf_ipv6_ops __read_mostly; EXPORT_SYMBOL_GPL(nf_ipv6_ops); +DEFINE_PER_CPU(bool, nf_skb_duplicated); +EXPORT_SYMBOL_GPL(nf_skb_duplicated); + int nf_register_afinfo(const struct nf_afinfo *afinfo) { mutex_lock(&afinfo_mutex); @@ -58,9 +61,6 @@ void nf_unregister_afinfo(const struct nf_afinfo *afinfo) } EXPORT_SYMBOL_GPL(nf_unregister_afinfo); -struct list_head nf_hooks[NFPROTO_NUMPROTO][NF_MAX_HOOKS] __read_mostly; -EXPORT_SYMBOL(nf_hooks); - #ifdef HAVE_JUMP_LABEL struct static_key nf_hooks_needed[NFPROTO_NUMPROTO][NF_MAX_HOOKS]; EXPORT_SYMBOL(nf_hooks_needed); @@ -68,33 +68,168 @@ EXPORT_SYMBOL(nf_hooks_needed); static DEFINE_MUTEX(nf_hook_mutex); -int nf_register_hook(struct nf_hook_ops *reg) +static struct list_head *nf_find_hook_list(struct net *net, + const struct nf_hook_ops *reg) +{ + struct list_head *hook_list = NULL; + + if (reg->pf != NFPROTO_NETDEV) + hook_list = &net->nf.hooks[reg->pf][reg->hooknum]; + else if (reg->hooknum == NF_NETDEV_INGRESS) { +#ifdef CONFIG_NETFILTER_INGRESS + if (reg->dev && dev_net(reg->dev) == net) + hook_list = ®->dev->nf_hooks_ingress; +#endif + } + return hook_list; +} + +struct nf_hook_entry { + const struct nf_hook_ops *orig_ops; + struct nf_hook_ops ops; +}; + +int nf_register_net_hook(struct net *net, const struct nf_hook_ops *reg) { + struct list_head *hook_list; + struct nf_hook_entry *entry; struct nf_hook_ops *elem; + entry = kmalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return -ENOMEM; + + entry->orig_ops = reg; + entry->ops = *reg; + + hook_list = nf_find_hook_list(net, reg); + if (!hook_list) { + kfree(entry); + return -ENOENT; + } + mutex_lock(&nf_hook_mutex); - list_for_each_entry(elem, &nf_hooks[reg->pf][reg->hooknum], list) { + list_for_each_entry(elem, hook_list, list) { if (reg->priority < elem->priority) break; } - list_add_rcu(®->list, elem->list.prev); + list_add_rcu(&entry->ops.list, elem->list.prev); mutex_unlock(&nf_hook_mutex); +#ifdef CONFIG_NETFILTER_INGRESS + if (reg->pf == NFPROTO_NETDEV && reg->hooknum == NF_NETDEV_INGRESS) + net_inc_ingress_queue(); +#endif #ifdef HAVE_JUMP_LABEL static_key_slow_inc(&nf_hooks_needed[reg->pf][reg->hooknum]); #endif return 0; } -EXPORT_SYMBOL(nf_register_hook); +EXPORT_SYMBOL(nf_register_net_hook); -void nf_unregister_hook(struct nf_hook_ops *reg) +void nf_unregister_net_hook(struct net *net, const struct nf_hook_ops *reg) { + struct list_head *hook_list; + struct nf_hook_entry *entry; + struct nf_hook_ops *elem; + + hook_list = nf_find_hook_list(net, reg); + if (!hook_list) + return; + mutex_lock(&nf_hook_mutex); - list_del_rcu(®->list); + list_for_each_entry(elem, hook_list, list) { + entry = container_of(elem, struct nf_hook_entry, ops); + if (entry->orig_ops == reg) { + list_del_rcu(&entry->ops.list); + break; + } + } mutex_unlock(&nf_hook_mutex); + if (&elem->list == hook_list) { + WARN(1, "nf_unregister_net_hook: hook not found!\n"); + return; + } +#ifdef CONFIG_NETFILTER_INGRESS + if (reg->pf == NFPROTO_NETDEV && reg->hooknum == NF_NETDEV_INGRESS) + net_dec_ingress_queue(); +#endif #ifdef HAVE_JUMP_LABEL static_key_slow_dec(&nf_hooks_needed[reg->pf][reg->hooknum]); #endif synchronize_net(); + nf_queue_nf_hook_drop(net, &entry->ops); + /* other cpu might still process nfqueue verdict that used reg */ + synchronize_net(); + kfree(entry); +} +EXPORT_SYMBOL(nf_unregister_net_hook); + +int nf_register_net_hooks(struct net *net, const struct nf_hook_ops *reg, + unsigned int n) +{ + unsigned int i; + int err = 0; + + for (i = 0; i < n; i++) { + err = nf_register_net_hook(net, ®[i]); + if (err) + goto err; + } + return err; + +err: + if (i > 0) + nf_unregister_net_hooks(net, reg, i); + return err; +} +EXPORT_SYMBOL(nf_register_net_hooks); + +void nf_unregister_net_hooks(struct net *net, const struct nf_hook_ops *reg, + unsigned int n) +{ + while (n-- > 0) + nf_unregister_net_hook(net, ®[n]); +} +EXPORT_SYMBOL(nf_unregister_net_hooks); + +static LIST_HEAD(nf_hook_list); + +int nf_register_hook(struct nf_hook_ops *reg) +{ + struct net *net, *last; + int ret; + + rtnl_lock(); + for_each_net(net) { + ret = nf_register_net_hook(net, reg); + if (ret && ret != -ENOENT) + goto rollback; + } + list_add_tail(®->list, &nf_hook_list); + rtnl_unlock(); + + return 0; +rollback: + last = net; + for_each_net(net) { + if (net == last) + break; + nf_unregister_net_hook(net, reg); + } + rtnl_unlock(); + return ret; +} +EXPORT_SYMBOL(nf_register_hook); + +void nf_unregister_hook(struct nf_hook_ops *reg) +{ + struct net *net; + + rtnl_lock(); + list_del(®->list); + for_each_net(net) + nf_unregister_net_hook(net, reg); + rtnl_unlock(); } EXPORT_SYMBOL(nf_unregister_hook); @@ -142,7 +277,7 @@ unsigned int nf_iterate(struct list_head *head, /* Optimization: we don't need to hold module reference here, since function can't sleep. --RR */ repeat: - verdict = (*elemp)->hook(*elemp, skb, state); + verdict = (*elemp)->hook((*elemp)->priv, skb, state); if (verdict != NF_ACCEPT) { #ifdef CONFIG_NETFILTER_DEBUG if (unlikely((verdict & NF_VERDICT_MASK) @@ -172,11 +307,9 @@ int nf_hook_slow(struct sk_buff *skb, struct nf_hook_state *state) /* We may already have this, but read-locks nest anyway */ rcu_read_lock(); - elem = list_entry_rcu(&nf_hooks[state->pf][state->hook], - struct nf_hook_ops, list); + elem = list_entry_rcu(state->hook_list, struct nf_hook_ops, list); next_hook: - verdict = nf_iterate(&nf_hooks[state->pf][state->hook], skb, state, - &elem); + verdict = nf_iterate(state->hook_list, skb, state, &elem); if (verdict == NF_ACCEPT || verdict == NF_STOP) { ret = 1; } else if ((verdict & NF_VERDICT_MASK) == NF_DROP) { @@ -188,8 +321,6 @@ next_hook: int err = nf_queue(skb, elem, state, verdict >> NF_VERDICT_QBITS); if (err < 0) { - if (err == -ECANCELED) - goto next_hook; if (err == -ESRCH && (verdict & NF_VERDICT_FLAG_QUEUE_BYPASS)) goto next_hook; @@ -223,6 +354,12 @@ int skb_make_writable(struct sk_buff *skb, unsigned int writable_len) } EXPORT_SYMBOL(skb_make_writable); +/* This needs to be compiled in any case to avoid dependencies between the + * nfnetlink_queue code and nf_conntrack. + */ +struct nfnl_ct_hook __rcu *nfnl_ct_hook __read_mostly; +EXPORT_SYMBOL_GPL(nfnl_ct_hook); + #if IS_ENABLED(CONFIG_NF_CONNTRACK) /* This does not belong here, but locally generated errors need it if connection tracking in use: without this, connection may not be in hash table, and hence @@ -260,12 +397,12 @@ void nf_conntrack_destroy(struct nf_conntrack *nfct) } EXPORT_SYMBOL(nf_conntrack_destroy); -struct nfq_ct_hook __rcu *nfq_ct_hook __read_mostly; -EXPORT_SYMBOL_GPL(nfq_ct_hook); - -struct nfq_ct_nat_hook __rcu *nfq_ct_nat_hook __read_mostly; -EXPORT_SYMBOL_GPL(nfq_ct_nat_hook); - +/* Built-in default zone used e.g. by modules. */ +const struct nf_conntrack_zone nf_ct_zone_dflt = { + .id = NF_CT_DEFAULT_ZONE_ID, + .dir = NF_CT_DEFAULT_ZONE_DIR, +}; +EXPORT_SYMBOL_GPL(nf_ct_zone_dflt); #endif /* CONFIG_NF_CONNTRACK */ #ifdef CONFIG_NF_NAT_NEEDED @@ -273,8 +410,46 @@ void (*nf_nat_decode_session_hook)(struct sk_buff *, struct flowi *); EXPORT_SYMBOL(nf_nat_decode_session_hook); #endif +static int nf_register_hook_list(struct net *net) +{ + struct nf_hook_ops *elem; + int ret; + + rtnl_lock(); + list_for_each_entry(elem, &nf_hook_list, list) { + ret = nf_register_net_hook(net, elem); + if (ret && ret != -ENOENT) + goto out_undo; + } + rtnl_unlock(); + return 0; + +out_undo: + list_for_each_entry_continue_reverse(elem, &nf_hook_list, list) + nf_unregister_net_hook(net, elem); + rtnl_unlock(); + return ret; +} + +static void nf_unregister_hook_list(struct net *net) +{ + struct nf_hook_ops *elem; + + rtnl_lock(); + list_for_each_entry(elem, &nf_hook_list, list) + nf_unregister_net_hook(net, elem); + rtnl_unlock(); +} + static int __net_init netfilter_net_init(struct net *net) { + int i, h, ret; + + for (i = 0; i < ARRAY_SIZE(net->nf.hooks); i++) { + for (h = 0; h < NF_MAX_HOOKS; h++) + INIT_LIST_HEAD(&net->nf.hooks[i][h]); + } + #ifdef CONFIG_PROC_FS net->nf.proc_netfilter = proc_net_mkdir(net, "netfilter", net->proc_net); @@ -285,11 +460,16 @@ static int __net_init netfilter_net_init(struct net *net) return -ENOMEM; } #endif - return 0; + ret = nf_register_hook_list(net); + if (ret) + remove_proc_entry("netfilter", net->proc_net); + + return ret; } static void __net_exit netfilter_net_exit(struct net *net) { + nf_unregister_hook_list(net); remove_proc_entry("netfilter", net->proc_net); } @@ -300,12 +480,7 @@ static struct pernet_operations netfilter_net_ops = { int __init netfilter_init(void) { - int i, h, ret; - - for (i = 0; i < ARRAY_SIZE(nf_hooks); i++) { - for (h = 0; h < NF_MAX_HOOKS; h++) - INIT_LIST_HEAD(&nf_hooks[i][h]); - } + int ret; ret = register_pernet_subsys(&netfilter_net_ops); if (ret < 0) |