netfilter: Introduce NFPROTO_* constants
[safe/jmp/linux-2.6] / net / netfilter / nf_queue.c
index c61f723..4f2310c 100644 (file)
@@ -1,4 +1,3 @@
-#include <linux/config.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/seq_file.h>
 #include <linux/rcupdate.h>
 #include <net/protocol.h>
+#include <net/netfilter/nf_queue.h>
 
 #include "nf_internals.h"
 
-/* 
+/*
  * A queue handler may be registered for each protocol.  Each is protected by
  * long term mutex.  The handler must provide an an outfn() to accept packets
  * for queueing and must reinject all packets it receives, no matter what.
  */
-static struct nf_queue_handler *queue_handler[NPROTO];
-static struct nf_queue_rerouter *queue_rerouter[NPROTO];
+static const struct nf_queue_handler *queue_handler[NFPROTO_NUMPROTO] __read_mostly;
 
-static DEFINE_RWLOCK(queue_handler_lock);
+static DEFINE_MUTEX(queue_handler_mutex);
 
 /* return EBUSY when somebody else is registered, return EEXIST if the
  * same handler is registered, return 0 in case of success. */
-int nf_register_queue_handler(int pf, struct nf_queue_handler *qh)
-{      
+int nf_register_queue_handler(u_int8_t pf, const struct nf_queue_handler *qh)
+{
        int ret;
 
-       if (pf >= NPROTO)
+       if (pf >= ARRAY_SIZE(queue_handler))
                return -EINVAL;
 
-       write_lock_bh(&queue_handler_lock);
+       mutex_lock(&queue_handler_mutex);
        if (queue_handler[pf] == qh)
                ret = -EEXIST;
        else if (queue_handler[pf])
                ret = -EBUSY;
        else {
-               queue_handler[pf] = qh;
+               rcu_assign_pointer(queue_handler[pf], qh);
                ret = 0;
        }
-       write_unlock_bh(&queue_handler_lock);
+       mutex_unlock(&queue_handler_mutex);
 
        return ret;
 }
 EXPORT_SYMBOL(nf_register_queue_handler);
 
 /* The caller must flush their queue before this */
-int nf_unregister_queue_handler(int pf)
+int nf_unregister_queue_handler(u_int8_t pf, const struct nf_queue_handler *qh)
 {
-       if (pf >= NPROTO)
+       if (pf >= ARRAY_SIZE(queue_handler))
                return -EINVAL;
 
-       write_lock_bh(&queue_handler_lock);
-       queue_handler[pf] = NULL;
-       write_unlock_bh(&queue_handler_lock);
-       
-       return 0;
-}
-EXPORT_SYMBOL(nf_unregister_queue_handler);
-
-int nf_register_queue_rerouter(int pf, struct nf_queue_rerouter *rer)
-{
-       if (pf >= NPROTO)
+       mutex_lock(&queue_handler_mutex);
+       if (queue_handler[pf] && queue_handler[pf] != qh) {
+               mutex_unlock(&queue_handler_mutex);
                return -EINVAL;
+       }
 
-       write_lock_bh(&queue_handler_lock);
-       rcu_assign_pointer(queue_rerouter[pf], rer);
-       write_unlock_bh(&queue_handler_lock);
+       rcu_assign_pointer(queue_handler[pf], NULL);
+       mutex_unlock(&queue_handler_mutex);
+
+       synchronize_rcu();
 
        return 0;
 }
-EXPORT_SYMBOL_GPL(nf_register_queue_rerouter);
+EXPORT_SYMBOL(nf_unregister_queue_handler);
 
-int nf_unregister_queue_rerouter(int pf)
+void nf_unregister_queue_handlers(const struct nf_queue_handler *qh)
 {
-       if (pf >= NPROTO)
-               return -EINVAL;
+       u_int8_t pf;
+
+       mutex_lock(&queue_handler_mutex);
+       for (pf = 0; pf < ARRAY_SIZE(queue_handler); pf++)  {
+               if (queue_handler[pf] == qh)
+                       rcu_assign_pointer(queue_handler[pf], NULL);
+       }
+       mutex_unlock(&queue_handler_mutex);
 
-       write_lock_bh(&queue_handler_lock);
-       rcu_assign_pointer(queue_rerouter[pf], NULL);
-       write_unlock_bh(&queue_handler_lock);
        synchronize_rcu();
-       return 0;
 }
-EXPORT_SYMBOL_GPL(nf_unregister_queue_rerouter);
+EXPORT_SYMBOL_GPL(nf_unregister_queue_handlers);
 
-void nf_unregister_queue_handlers(struct nf_queue_handler *qh)
+static void nf_queue_entry_release_refs(struct nf_queue_entry *entry)
 {
-       int pf;
+       /* Release those devices we held, or Alexey will kill me. */
+       if (entry->indev)
+               dev_put(entry->indev);
+       if (entry->outdev)
+               dev_put(entry->outdev);
+#ifdef CONFIG_BRIDGE_NETFILTER
+       if (entry->skb->nf_bridge) {
+               struct nf_bridge_info *nf_bridge = entry->skb->nf_bridge;
 
-       write_lock_bh(&queue_handler_lock);
-       for (pf = 0; pf < NPROTO; pf++)  {
-               if (queue_handler[pf] == qh)
-                       queue_handler[pf] = NULL;
+               if (nf_bridge->physindev)
+                       dev_put(nf_bridge->physindev);
+               if (nf_bridge->physoutdev)
+                       dev_put(nf_bridge->physoutdev);
        }
-       write_unlock_bh(&queue_handler_lock);
+#endif
+       /* Drop reference to owner of hook which queued us. */
+       module_put(entry->elem->owner);
 }
-EXPORT_SYMBOL_GPL(nf_unregister_queue_handlers);
 
-/* 
- * Any packet that leaves via this function must come back 
+/*
+ * Any packet that leaves via this function must come back
  * through nf_reinject().
  */
-int nf_queue(struct sk_buff **skb, 
-            struct list_head *elem, 
-            int pf, unsigned int hook,
-            struct net_device *indev,
-            struct net_device *outdev,
-            int (*okfn)(struct sk_buff *),
-            unsigned int queuenum)
+static int __nf_queue(struct sk_buff *skb,
+                     struct list_head *elem,
+                     u_int8_t pf, unsigned int hook,
+                     struct net_device *indev,
+                     struct net_device *outdev,
+                     int (*okfn)(struct sk_buff *),
+                     unsigned int queuenum)
 {
        int status;
-       struct nf_info *info;
+       struct nf_queue_entry *entry = NULL;
 #ifdef CONFIG_BRIDGE_NETFILTER
-       struct net_device *physindev = NULL;
-       struct net_device *physoutdev = NULL;
+       struct net_device *physindev;
+       struct net_device *physoutdev;
 #endif
-       struct nf_queue_rerouter *rerouter;
+       const struct nf_afinfo *afinfo;
+       const struct nf_queue_handler *qh;
 
        /* QUEUE == DROP if noone is waiting, to be safe. */
-       read_lock(&queue_handler_lock);
-       if (!queue_handler[pf] || !queue_handler[pf]->outfn) {
-               read_unlock(&queue_handler_lock);
-               kfree_skb(*skb);
-               return 1;
-       }
-
-       info = kmalloc(sizeof(*info)+queue_rerouter[pf]->rer_size, GFP_ATOMIC);
-       if (!info) {
-               if (net_ratelimit())
-                       printk(KERN_ERR "OOM queueing packet %p\n",
-                              *skb);
-               read_unlock(&queue_handler_lock);
-               kfree_skb(*skb);
-               return 1;
-       }
+       rcu_read_lock();
 
-       *info = (struct nf_info) { 
-               (struct nf_hook_ops *)elem, pf, hook, indev, outdev, okfn };
+       qh = rcu_dereference(queue_handler[pf]);
+       if (!qh)
+               goto err_unlock;
+
+       afinfo = nf_get_afinfo(pf);
+       if (!afinfo)
+               goto err_unlock;
+
+       entry = kmalloc(sizeof(*entry) + afinfo->route_key_size, GFP_ATOMIC);
+       if (!entry)
+               goto err_unlock;
+
+       *entry = (struct nf_queue_entry) {
+               .skb    = skb,
+               .elem   = list_entry(elem, struct nf_hook_ops, list),
+               .pf     = pf,
+               .hook   = hook,
+               .indev  = indev,
+               .outdev = outdev,
+               .okfn   = okfn,
+       };
 
        /* If it's going away, ignore hook. */
-       if (!try_module_get(info->elem->owner)) {
-               read_unlock(&queue_handler_lock);
-               kfree(info);
+       if (!try_module_get(entry->elem->owner)) {
+               rcu_read_unlock();
+               kfree(entry);
                return 0;
        }
 
        /* Bump dev refs so they don't vanish while packet is out */
-       if (indev) dev_hold(indev);
-       if (outdev) dev_hold(outdev);
-
+       if (indev)
+               dev_hold(indev);
+       if (outdev)
+               dev_hold(outdev);
 #ifdef CONFIG_BRIDGE_NETFILTER
-       if ((*skb)->nf_bridge) {
-               physindev = (*skb)->nf_bridge->physindev;
-               if (physindev) dev_hold(physindev);
-               physoutdev = (*skb)->nf_bridge->physoutdev;
-               if (physoutdev) dev_hold(physoutdev);
+       if (skb->nf_bridge) {
+               physindev = skb->nf_bridge->physindev;
+               if (physindev)
+                       dev_hold(physindev);
+               physoutdev = skb->nf_bridge->physoutdev;
+               if (physoutdev)
+                       dev_hold(physoutdev);
        }
 #endif
-       rerouter = rcu_dereference(queue_rerouter[pf]);
-       if (rerouter)
-               rerouter->save(*skb, info);
-
-       status = queue_handler[pf]->outfn(*skb, info, queuenum,
-                                         queue_handler[pf]->data);
+       afinfo->saveroute(skb, entry);
+       status = qh->outfn(entry, queuenum);
 
-       read_unlock(&queue_handler_lock);
+       rcu_read_unlock();
 
        if (status < 0) {
-               /* James M doesn't say fuck enough. */
-               if (indev) dev_put(indev);
-               if (outdev) dev_put(outdev);
-#ifdef CONFIG_BRIDGE_NETFILTER
-               if (physindev) dev_put(physindev);
-               if (physoutdev) dev_put(physoutdev);
-#endif
-               module_put(info->elem->owner);
-               kfree(info);
-               kfree_skb(*skb);
-
-               return 1;
+               nf_queue_entry_release_refs(entry);
+               goto err;
        }
 
        return 1;
+
+err_unlock:
+       rcu_read_unlock();
+err:
+       kfree_skb(skb);
+       kfree(entry);
+       return 1;
 }
 
-void nf_reinject(struct sk_buff *skb, struct nf_info *info,
-                unsigned int verdict)
+int nf_queue(struct sk_buff *skb,
+            struct list_head *elem,
+            u_int8_t pf, unsigned int hook,
+            struct net_device *indev,
+            struct net_device *outdev,
+            int (*okfn)(struct sk_buff *),
+            unsigned int queuenum)
 {
-       struct list_head *elem = &info->elem->list;
-       struct list_head *i;
-       struct nf_queue_rerouter *rerouter;
+       struct sk_buff *segs;
 
-       rcu_read_lock();
+       if (!skb_is_gso(skb))
+               return __nf_queue(skb, elem, pf, hook, indev, outdev, okfn,
+                                 queuenum);
 
-       /* Release those devices we held, or Alexey will kill me. */
-       if (info->indev) dev_put(info->indev);
-       if (info->outdev) dev_put(info->outdev);
-#ifdef CONFIG_BRIDGE_NETFILTER
-       if (skb->nf_bridge) {
-               if (skb->nf_bridge->physindev)
-                       dev_put(skb->nf_bridge->physindev);
-               if (skb->nf_bridge->physoutdev)
-                       dev_put(skb->nf_bridge->physoutdev);
+       switch (pf) {
+       case AF_INET:
+               skb->protocol = htons(ETH_P_IP);
+               break;
+       case AF_INET6:
+               skb->protocol = htons(ETH_P_IPV6);
+               break;
        }
-#endif
 
-       /* Drop reference to owner of hook which queued us. */
-       module_put(info->elem->owner);
-
-       list_for_each_rcu(i, &nf_hooks[info->pf][info->hook]) {
-               if (i == elem) 
-                       break;
-       }
-  
-       if (elem == &nf_hooks[info->pf][info->hook]) {
-               /* The module which sent it to userspace is gone. */
-               NFDEBUG("%s: module disappeared, dropping packet.\n",
-                       __FUNCTION__);
-               verdict = NF_DROP;
-       }
+       segs = skb_gso_segment(skb, 0);
+       kfree_skb(skb);
+       if (IS_ERR(segs))
+               return 1;
+
+       do {
+               struct sk_buff *nskb = segs->next;
+
+               segs->next = NULL;
+               if (!__nf_queue(segs, elem, pf, hook, indev, outdev, okfn,
+                               queuenum))
+                       kfree_skb(segs);
+               segs = nskb;
+       } while (segs);
+       return 1;
+}
+
+void nf_reinject(struct nf_queue_entry *entry, unsigned int verdict)
+{
+       struct sk_buff *skb = entry->skb;
+       struct list_head *elem = &entry->elem->list;
+       const struct nf_afinfo *afinfo;
+
+       rcu_read_lock();
+
+       nf_queue_entry_release_refs(entry);
 
        /* Continue traversal iff userspace said ok... */
        if (verdict == NF_REPEAT) {
@@ -228,37 +246,38 @@ void nf_reinject(struct sk_buff *skb, struct nf_info *info,
        }
 
        if (verdict == NF_ACCEPT) {
-               rerouter = rcu_dereference(queue_rerouter[info->pf]);
-               if (rerouter && rerouter->reroute(&skb, info) < 0)
+               afinfo = nf_get_afinfo(entry->pf);
+               if (!afinfo || afinfo->reroute(skb, entry) < 0)
                        verdict = NF_DROP;
        }
 
        if (verdict == NF_ACCEPT) {
        next_hook:
-               verdict = nf_iterate(&nf_hooks[info->pf][info->hook],
-                                    &skb, info->hook, 
-                                    info->indev, info->outdev, &elem,
-                                    info->okfn, INT_MIN);
+               verdict = nf_iterate(&nf_hooks[entry->pf][entry->hook],
+                                    skb, entry->hook,
+                                    entry->indev, entry->outdev, &elem,
+                                    entry->okfn, INT_MIN);
        }
 
        switch (verdict & NF_VERDICT_MASK) {
        case NF_ACCEPT:
-               info->okfn(skb);
+       case NF_STOP:
+               local_bh_disable();
+               entry->okfn(skb);
+               local_bh_enable();
+       case NF_STOLEN:
                break;
-
        case NF_QUEUE:
-               if (!nf_queue(&skb, elem, info->pf, info->hook, 
-                             info->indev, info->outdev, info->okfn,
-                             verdict >> NF_VERDICT_BITS))
+               if (!__nf_queue(skb, elem, entry->pf, entry->hook,
+                               entry->indev, entry->outdev, entry->okfn,
+                               verdict >> NF_VERDICT_BITS))
                        goto next_hook;
                break;
+       default:
+               kfree_skb(skb);
        }
        rcu_read_unlock();
-
-       if (verdict == NF_DROP)
-               kfree_skb(skb);
-
-       kfree(info);
+       kfree(entry);
        return;
 }
 EXPORT_SYMBOL(nf_reinject);
@@ -266,7 +285,7 @@ EXPORT_SYMBOL(nf_reinject);
 #ifdef CONFIG_PROC_FS
 static void *seq_start(struct seq_file *seq, loff_t *pos)
 {
-       if (*pos >= NPROTO)
+       if (*pos >= ARRAY_SIZE(queue_handler))
                return NULL;
 
        return pos;
@@ -276,7 +295,7 @@ static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
 {
        (*pos)++;
 
-       if (*pos >= NPROTO)
+       if (*pos >= ARRAY_SIZE(queue_handler))
                return NULL;
 
        return pos;
@@ -291,20 +310,20 @@ static int seq_show(struct seq_file *s, void *v)
 {
        int ret;
        loff_t *pos = v;
-       struct nf_queue_handler *qh;
+       const struct nf_queue_handler *qh;
 
-       read_lock_bh(&queue_handler_lock);
-       qh = queue_handler[*pos];
+       rcu_read_lock();
+       qh = rcu_dereference(queue_handler[*pos]);
        if (!qh)
                ret = seq_printf(s, "%2lld NONE\n", *pos);
        else
                ret = seq_printf(s, "%2lld %s\n", *pos, qh->name);
-       read_unlock_bh(&queue_handler_lock);
+       rcu_read_unlock();
 
        return ret;
 }
 
-static struct seq_operations nfqueue_seq_ops = {
+static const struct seq_operations nfqueue_seq_ops = {
        .start  = seq_start,
        .next   = seq_next,
        .stop   = seq_stop,
@@ -316,7 +335,7 @@ static int nfqueue_open(struct inode *inode, struct file *file)
        return seq_open(file, &nfqueue_seq_ops);
 }
 
-static struct file_operations nfqueue_file_ops = {
+static const struct file_operations nfqueue_file_ops = {
        .owner   = THIS_MODULE,
        .open    = nfqueue_open,
        .read    = seq_read,
@@ -329,12 +348,9 @@ static struct file_operations nfqueue_file_ops = {
 int __init netfilter_queue_init(void)
 {
 #ifdef CONFIG_PROC_FS
-       struct proc_dir_entry *pde;
-
-       pde = create_proc_entry("nf_queue", S_IRUGO, proc_net_netfilter);
-       if (!pde)
+       if (!proc_create("nf_queue", S_IRUGO,
+                        proc_net_netfilter, &nfqueue_file_ops))
                return -1;
-       pde->proc_fops = &nfqueue_file_ops;
 #endif
        return 0;
 }