-/* netfilter.c: look after the filters for various protocols.
+/* netfilter.c: look after the filters for various protocols.
* Heavily influenced by the old firewall.c by David Bonn and Alan Cox.
*
* Thanks to Rob `CmdrTaco' Malda for not influencing this code in any
* way.
*
* Rusty Russell (C)2000 -- This code is GPL.
- *
- * February 2000: Modified by James Morris to have 1 queue per protocol.
- * 15-Mar-2000: Added NF_REPEAT --RR.
- * 08-May-2003: Internal logging interface added by Jozsef Kadlecsik.
*/
#include <linux/kernel.h>
#include <linux/netfilter.h>
#include <linux/netdevice.h>
#include <linux/inetdevice.h>
#include <linux/proc_fs.h>
+#include <linux/mutex.h>
+#include <net/net_namespace.h>
#include <net/sock.h>
#include "nf_internals.h"
-static DEFINE_SPINLOCK(afinfo_lock);
+static DEFINE_MUTEX(afinfo_mutex);
-struct nf_afinfo *nf_afinfo[NPROTO];
+const struct nf_afinfo *nf_afinfo[NFPROTO_NUMPROTO] __read_mostly;
EXPORT_SYMBOL(nf_afinfo);
-int nf_register_afinfo(struct nf_afinfo *afinfo)
+int nf_register_afinfo(const struct nf_afinfo *afinfo)
{
- spin_lock(&afinfo_lock);
+ int err;
+
+ err = mutex_lock_interruptible(&afinfo_mutex);
+ if (err < 0)
+ return err;
rcu_assign_pointer(nf_afinfo[afinfo->family], afinfo);
- spin_unlock(&afinfo_lock);
+ mutex_unlock(&afinfo_mutex);
return 0;
}
EXPORT_SYMBOL_GPL(nf_register_afinfo);
-void nf_unregister_afinfo(struct nf_afinfo *afinfo)
+void nf_unregister_afinfo(const struct nf_afinfo *afinfo)
{
- spin_lock(&afinfo_lock);
+ mutex_lock(&afinfo_mutex);
rcu_assign_pointer(nf_afinfo[afinfo->family], NULL);
- spin_unlock(&afinfo_lock);
+ mutex_unlock(&afinfo_mutex);
synchronize_rcu();
}
EXPORT_SYMBOL_GPL(nf_unregister_afinfo);
-/* In this code, we can be waiting indefinitely for userspace to
- * service a packet if a hook returns NF_QUEUE. We could keep a count
- * of skbuffs queued for userspace, and not deregister a hook unless
- * this is zero, but that sucks. Now, we simply check when the
- * packets come back: if the hook is gone, the packet is discarded. */
-struct list_head nf_hooks[NPROTO][NF_MAX_HOOKS];
+struct list_head nf_hooks[NFPROTO_NUMPROTO][NF_MAX_HOOKS] __read_mostly;
EXPORT_SYMBOL(nf_hooks);
-static DEFINE_SPINLOCK(nf_hook_lock);
+static DEFINE_MUTEX(nf_hook_mutex);
int nf_register_hook(struct nf_hook_ops *reg)
{
- struct list_head *i;
-
- spin_lock_bh(&nf_hook_lock);
- list_for_each(i, &nf_hooks[reg->pf][reg->hooknum]) {
- if (reg->priority < ((struct nf_hook_ops *)i)->priority)
+ struct nf_hook_ops *elem;
+ int err;
+
+ err = mutex_lock_interruptible(&nf_hook_mutex);
+ if (err < 0)
+ return err;
+ list_for_each_entry(elem, &nf_hooks[reg->pf][reg->hooknum], list) {
+ if (reg->priority < elem->priority)
break;
}
- list_add_rcu(®->list, i->prev);
- spin_unlock_bh(&nf_hook_lock);
-
- synchronize_net();
+ list_add_rcu(®->list, elem->list.prev);
+ mutex_unlock(&nf_hook_mutex);
return 0;
}
EXPORT_SYMBOL(nf_register_hook);
void nf_unregister_hook(struct nf_hook_ops *reg)
{
- spin_lock_bh(&nf_hook_lock);
+ mutex_lock(&nf_hook_mutex);
list_del_rcu(®->list);
- spin_unlock_bh(&nf_hook_lock);
+ mutex_unlock(&nf_hook_mutex);
synchronize_net();
}
EXPORT_SYMBOL(nf_unregister_hooks);
unsigned int nf_iterate(struct list_head *head,
- struct sk_buff **skb,
- int hook,
+ struct sk_buff *skb,
+ unsigned int hook,
const struct net_device *indev,
const struct net_device *outdev,
struct list_head **i,
continue;
/* Optimization: we don't need to hold module
- reference here, since function can't sleep. --RR */
+ reference here, since function can't sleep. --RR */
verdict = elem->hook(hook, skb, indev, outdev, okfn);
if (verdict != NF_ACCEPT) {
#ifdef CONFIG_NETFILTER_DEBUG
if (unlikely((verdict & NF_VERDICT_MASK)
> NF_MAX_VERDICT)) {
NFDEBUG("Evil return from %p(%u).\n",
- elem->hook, hook);
+ elem->hook, hook);
continue;
}
#endif
/* Returns 1 if okfn() needs to be executed by the caller,
* -EPERM for NF_DROP, 0 otherwise. */
-int nf_hook_slow(int pf, unsigned int hook, struct sk_buff **pskb,
+int nf_hook_slow(u_int8_t pf, unsigned int hook, struct sk_buff *skb,
struct net_device *indev,
struct net_device *outdev,
int (*okfn)(struct sk_buff *),
elem = &nf_hooks[pf][hook];
next_hook:
- verdict = nf_iterate(&nf_hooks[pf][hook], pskb, hook, indev,
+ verdict = nf_iterate(&nf_hooks[pf][hook], skb, hook, indev,
outdev, &elem, okfn, hook_thresh);
if (verdict == NF_ACCEPT || verdict == NF_STOP) {
ret = 1;
- goto unlock;
} else if (verdict == NF_DROP) {
- kfree_skb(*pskb);
+ kfree_skb(skb);
ret = -EPERM;
- } else if ((verdict & NF_VERDICT_MASK) == NF_QUEUE) {
- NFDEBUG("nf_hook: Verdict = QUEUE.\n");
- if (!nf_queue(pskb, elem, pf, hook, indev, outdev, okfn,
+ } else if ((verdict & NF_VERDICT_MASK) == NF_QUEUE) {
+ if (!nf_queue(skb, elem, pf, hook, indev, outdev, okfn,
verdict >> NF_VERDICT_BITS))
goto next_hook;
}
-unlock:
rcu_read_unlock();
return ret;
}
EXPORT_SYMBOL(nf_hook_slow);
-int skb_make_writable(struct sk_buff **pskb, unsigned int writable_len)
+int skb_make_writable(struct sk_buff *skb, unsigned int writable_len)
{
- struct sk_buff *nskb;
-
- if (writable_len > (*pskb)->len)
+ if (writable_len > skb->len)
return 0;
/* Not exclusive use of packet? Must copy. */
- if (skb_shared(*pskb) || skb_cloned(*pskb))
- goto copy_skb;
-
- return pskb_may_pull(*pskb, writable_len);
-
-copy_skb:
- nskb = skb_copy(*pskb, GFP_ATOMIC);
- if (!nskb)
- return 0;
- BUG_ON(skb_is_nonlinear(nskb));
-
- /* Rest of kernel will get very unhappy if we pass it a
- suddenly-orphaned skbuff */
- if ((*pskb)->sk)
- skb_set_owner_w(nskb, (*pskb)->sk);
- kfree_skb(*pskb);
- *pskb = nskb;
- return 1;
+ if (!skb_cloned(skb)) {
+ if (writable_len <= skb_headlen(skb))
+ return 1;
+ } else if (skb_clone_writable(skb, writable_len))
+ return 1;
+
+ if (writable_len <= skb_headlen(skb))
+ writable_len = 0;
+ else
+ writable_len -= skb_headlen(skb);
+
+ return !!__pskb_pull_tail(skb, writable_len);
}
EXPORT_SYMBOL(skb_make_writable);
-u_int16_t nf_csum_update(u_int32_t oldval, u_int32_t newval, u_int32_t csum)
-{
- u_int32_t diff[] = { oldval, newval };
-
- return csum_fold(csum_partial((char *)diff, sizeof(diff), ~csum));
-}
-EXPORT_SYMBOL(nf_csum_update);
-
-u_int16_t nf_proto_csum_update(struct sk_buff *skb,
- u_int32_t oldval, u_int32_t newval,
- u_int16_t csum, int pseudohdr)
-{
- if (skb->ip_summed != CHECKSUM_PARTIAL) {
- csum = nf_csum_update(oldval, newval, csum);
- if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
- skb->csum = nf_csum_update(oldval, newval, skb->csum);
- } else if (pseudohdr)
- csum = ~nf_csum_update(oldval, newval, ~csum);
-
- return csum;
-}
-EXPORT_SYMBOL(nf_proto_csum_update);
-
+#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
/* 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
manufactured ICMP or RST packets will not be associated with it. */
{
void (*attach)(struct sk_buff *, struct sk_buff *);
- if (skb->nfct && (attach = ip_ct_attach) != NULL) {
- mb(); /* Just to be sure: must be read before executing this */
- attach(new, skb);
+ if (skb->nfct) {
+ rcu_read_lock();
+ attach = rcu_dereference(ip_ct_attach);
+ if (attach)
+ attach(new, skb);
+ rcu_read_unlock();
}
}
EXPORT_SYMBOL(nf_ct_attach);
+void (*nf_ct_destroy)(struct nf_conntrack *);
+EXPORT_SYMBOL(nf_ct_destroy);
+
+void nf_conntrack_destroy(struct nf_conntrack *nfct)
+{
+ void (*destroy)(struct nf_conntrack *);
+
+ rcu_read_lock();
+ destroy = rcu_dereference(nf_ct_destroy);
+ BUG_ON(destroy == NULL);
+ destroy(nfct);
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL(nf_conntrack_destroy);
+#endif /* CONFIG_NF_CONNTRACK */
+
#ifdef CONFIG_PROC_FS
struct proc_dir_entry *proc_net_netfilter;
EXPORT_SYMBOL(proc_net_netfilter);
void __init netfilter_init(void)
{
int i, h;
- for (i = 0; i < NPROTO; i++) {
+ for (i = 0; i < ARRAY_SIZE(nf_hooks); i++) {
for (h = 0; h < NF_MAX_HOOKS; h++)
INIT_LIST_HEAD(&nf_hooks[i][h]);
}
#ifdef CONFIG_PROC_FS
- proc_net_netfilter = proc_mkdir("netfilter", proc_net);
+ proc_net_netfilter = proc_mkdir("netfilter", init_net.proc_net);
if (!proc_net_netfilter)
panic("cannot create netfilter proc entry");
#endif
if (netfilter_log_init() < 0)
panic("cannot initialize nf_log");
}
+
+#ifdef CONFIG_SYSCTL
+struct ctl_path nf_net_netfilter_sysctl_path[] = {
+ { .procname = "net", },
+ { .procname = "netfilter", },
+ { }
+};
+EXPORT_SYMBOL_GPL(nf_net_netfilter_sysctl_path);
+#endif /* CONFIG_SYSCTL */
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff