Merge master.kernel.org:/home/rmk/linux-2.6-arm
[safe/jmp/linux-2.6] / net / netfilter / core.c
index a84478e..78b505d 100644 (file)
 #include <linux/inetdevice.h>
 #include <linux/proc_fs.h>
 #include <linux/mutex.h>
+#include <linux/slab.h>
+#include <net/net_namespace.h>
 #include <net/sock.h>
 
 #include "nf_internals.h"
 
 static DEFINE_MUTEX(afinfo_mutex);
 
-struct nf_afinfo *nf_afinfo[NPROTO] __read_mostly;
+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)
 {
        int err;
 
@@ -41,7 +43,7 @@ int nf_register_afinfo(struct nf_afinfo *afinfo)
 }
 EXPORT_SYMBOL_GPL(nf_register_afinfo);
 
-void nf_unregister_afinfo(struct nf_afinfo *afinfo)
+void nf_unregister_afinfo(const struct nf_afinfo *afinfo)
 {
        mutex_lock(&afinfo_mutex);
        rcu_assign_pointer(nf_afinfo[afinfo->family], NULL);
@@ -50,28 +52,23 @@ void nf_unregister_afinfo(struct nf_afinfo *afinfo)
 }
 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] __read_mostly;
+struct list_head nf_hooks[NFPROTO_NUMPROTO][NF_MAX_HOOKS] __read_mostly;
 EXPORT_SYMBOL(nf_hooks);
 static DEFINE_MUTEX(nf_hook_mutex);
 
 int nf_register_hook(struct nf_hook_ops *reg)
 {
-       struct list_head *i;
+       struct nf_hook_ops *elem;
        int err;
 
        err = mutex_lock_interruptible(&nf_hook_mutex);
        if (err < 0)
                return err;
-       list_for_each(i, &nf_hooks[reg->pf][reg->hooknum]) {
-               if (reg->priority < ((struct nf_hook_ops *)i)->priority)
+       list_for_each_entry(elem, &nf_hooks[reg->pf][reg->hooknum], list) {
+               if (reg->priority < elem->priority)
                        break;
        }
-       list_add_rcu(&reg->list, i->prev);
+       list_add_rcu(&reg->list, elem->list.prev);
        mutex_unlock(&nf_hook_mutex);
        return 0;
 }
@@ -116,8 +113,8 @@ void nf_unregister_hooks(struct nf_hook_ops *reg, unsigned int n)
 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,
@@ -159,7 +156,7 @@ unsigned int nf_iterate(struct list_head *head,
 
 /* 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 *),
@@ -174,72 +171,45 @@ int nf_hook_slow(int pf, unsigned int hook, struct sk_buff **pskb,
 
        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);
 
-void nf_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb,
-                           __be32 from, __be32 to, int pseudohdr)
-{
-       __be32 diff[] = { ~from, to };
-       if (skb->ip_summed != CHECKSUM_PARTIAL) {
-               *sum = csum_fold(csum_partial((char *)diff, sizeof(diff),
-                               ~csum_unfold(*sum)));
-               if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
-                       skb->csum = ~csum_partial((char *)diff, sizeof(diff),
-                                               ~skb->csum);
-       } else if (pseudohdr)
-               *sum = ~csum_fold(csum_partial((char *)diff, sizeof(diff),
-                               csum_unfold(*sum)));
-}
-EXPORT_SYMBOL(nf_proto_csum_replace4);
-
 #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
@@ -285,13 +255,13 @@ 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
@@ -301,3 +271,12 @@ void __init netfilter_init(void)
        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 */