[NETFILTER]: Move reroute-after-queue code up to the nf_queue layer.

The rerouting functionality is required by the core, therefore it has
to be implemented by the core and not in individual queue handlers.

Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 54 insertions, 12 deletions

diff --git a/net/core/netfilter.c b/net/core/netfilter.c
index 9849357f6129..1ed4f3110421 100644
--- a/net/core/netfilter.c
+++ b/net/core/netfilter.c
@@ -53,6 +53,9 @@ static struct nf_queue_handler_t {
         nf_queue_outfn_t outfn;
         void *data;
 } queue_handler[NPROTO];
+
+static struct nf_queue_rerouter *queue_rerouter;
+
 static DEFINE_RWLOCK(queue_handler_lock);
 
 int nf_register_hook(struct nf_hook_ops *reg)
@@ -260,11 +263,34 @@ int nf_unregister_queue_handler(int pf)
         return 0;
 }
 
+int nf_register_queue_rerouter(int pf, struct nf_queue_rerouter *rer)
+{
+        if (pf >= NPROTO)
+                return -EINVAL;
+
+        write_lock_bh(&queue_handler_lock);
+        memcpy(&queue_rerouter[pf], rer, sizeof(queue_rerouter[pf]));
+        write_unlock_bh(&queue_handler_lock);
+
+        return 0;
+}
+
+int nf_unregister_queue_rerouter(int pf)
+{
+        if (pf >= NPROTO)
+                return -EINVAL;
+
+        write_lock_bh(&queue_handler_lock);
+        memset(&queue_rerouter[pf], 0, sizeof(queue_rerouter[pf]));
+        write_unlock_bh(&queue_handler_lock);
+        return 0;
+}
+
 /* 
  * Any packet that leaves via this function must come back 
  * through nf_reinject().
  */
-static int nf_queue(struct sk_buff *skb, 
+static int nf_queue(struct sk_buff **skb, 
                     struct list_head *elem, 
                     int pf, unsigned int hook,
                     struct net_device *indev,
@@ -282,17 +308,17 @@ static int nf_queue(struct sk_buff *skb,
         read_lock(&queue_handler_lock);
         if (!queue_handler[pf].outfn) {
                 read_unlock(&queue_handler_lock);
-                kfree_skb(skb);
+                kfree_skb(*skb);
                 return 1;
         }
 
-        info = kmalloc(sizeof(*info), GFP_ATOMIC);
+        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);
+                               *skb);
                 read_unlock(&queue_handler_lock);
-                kfree_skb(skb);
+                kfree_skb(*skb);
                 return 1;
         }
 
@@ -311,15 +337,21 @@ static int nf_queue(struct sk_buff *skb,
         if (outdev) dev_hold(outdev);
 
 #ifdef CONFIG_BRIDGE_NETFILTER
-        if (skb->nf_bridge) {
-                physindev = skb->nf_bridge->physindev;
+        if ((*skb)->nf_bridge) {
+                physindev = (*skb)->nf_bridge->physindev;
                 if (physindev) dev_hold(physindev);
-                physoutdev = skb->nf_bridge->physoutdev;
+                physoutdev = (*skb)->nf_bridge->physoutdev;
                 if (physoutdev) dev_hold(physoutdev);
         }
 #endif
+        if (queue_rerouter[pf].save)
+                queue_rerouter[pf].save(*skb, info);
+
+        status = queue_handler[pf].outfn(*skb, info, queue_handler[pf].data);
+
+        if (status >= 0 && queue_rerouter[pf].reroute)
+                status = queue_rerouter[pf].reroute(skb, info);
 
-        status = queue_handler[pf].outfn(skb, info, queue_handler[pf].data);
         read_unlock(&queue_handler_lock);
 
         if (status < 0) {
@@ -332,9 +364,11 @@ static int nf_queue(struct sk_buff *skb,
 #endif
                 module_put(info->elem->owner);
                 kfree(info);
-                kfree_skb(skb);
+                kfree_skb(*skb);
+
                 return 1;
         }
+
         return 1;
 }
 
@@ -365,7 +399,7 @@ next_hook:
                 ret = -EPERM;
         } else if (verdict == NF_QUEUE) {
                 NFDEBUG("nf_hook: Verdict = QUEUE.\n");
-                if (!nf_queue(*pskb, elem, pf, hook, indev, outdev, okfn))
+                if (!nf_queue(pskb, elem, pf, hook, indev, outdev, okfn))
                         goto next_hook;
         }
 unlock:
@@ -428,7 +462,7 @@ void nf_reinject(struct sk_buff *skb, struct nf_info *info,
                 break;
 
         case NF_QUEUE:
-                if (!nf_queue(skb, elem, info->pf, info->hook, 
+                if (!nf_queue(&skb, elem, info->pf, info->hook, 
                               info->indev, info->outdev, info->okfn))
                         goto next_hook;
                 break;
@@ -555,6 +589,12 @@ void __init netfilter_init(void)
 {
         int i, h;
 
+        queue_rerouter = kmalloc(NPROTO * sizeof(struct nf_queue_rerouter),
+                                 GFP_KERNEL);
+        if (!queue_rerouter)
+                panic("netfilter: cannot allocate queue rerouter array\n");
+        memset(queue_rerouter, 0, NPROTO * sizeof(struct nf_queue_rerouter));
+
         for (i = 0; i < NPROTO; i++) {
                 for (h = 0; h < NF_MAX_HOOKS; h++)
                         INIT_LIST_HEAD(&nf_hooks[i][h]);
@@ -573,4 +613,6 @@ EXPORT_SYMBOL(nf_reinject);
 EXPORT_SYMBOL(nf_setsockopt);
 EXPORT_SYMBOL(nf_unregister_hook);
 EXPORT_SYMBOL(nf_unregister_queue_handler);
+EXPORT_SYMBOL_GPL(nf_register_queue_rerouter);
+EXPORT_SYMBOL_GPL(nf_unregister_queue_rerouter);
 EXPORT_SYMBOL(nf_unregister_sockopt);