[NETFILTER]: Add helper functions for mass hook registration/unregistration

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/netfilter.h

@@ -110,6 +110,8 @@ struct nf_info
 /* Function to register/unregister hook points. */
 int nf_register_hook(struct nf_hook_ops *reg);
 void nf_unregister_hook(struct nf_hook_ops *reg);
+int nf_register_hooks(struct nf_hook_ops *reg, unsigned int n);
+void nf_unregister_hooks(struct nf_hook_ops *reg, unsigned int n);
 
 /* Functions to register get/setsockopt ranges (non-inclusive).  You
    need to check permissions yourself! */

net/netfilter/core.c

@@ -63,6 +63,34 @@ void nf_unregister_hook(struct nf_hook_ops *reg)
 }
 EXPORT_SYMBOL(nf_unregister_hook);
 
+int nf_register_hooks(struct nf_hook_ops *reg, unsigned int n)
+{
+	unsigned int i;
+	int err = 0;
+
+	for (i = 0; i < n; i++) {
+		err = nf_register_hook(&reg[i]);
+		if (err)
+			goto err;
+	}
+	return err;
+
+err:
+	if (i > 0)
+		nf_unregister_hooks(reg, i);
+	return err;
+}
+EXPORT_SYMBOL(nf_register_hooks);
+
+void nf_unregister_hooks(struct nf_hook_ops *reg, unsigned int n)
+{
+	unsigned int i;
+
+	for (i = 0; i < n; i++)
+		nf_unregister_hook(&reg[i]);
+}
+EXPORT_SYMBOL(nf_unregister_hooks);
+
 unsigned int nf_iterate(struct list_head *head,
 			struct sk_buff **skb,
 			int hook,