netfilter: remove CONFIG_NETFILTER checks from headers.

`struct nf_hook_ops`, `struct nf_hook_state` and the `nf_hookfn`
function typedef appear in function and struct declarations and
definitions in a number of netfilter headers.  The structs and typedef
themselves are defined by linux/netfilter.h but only when
CONFIG_NETFILTER is enabled.  Define them unconditionally and add
forward declarations in order to remove CONFIG_NETFILTER conditionals
from the other headers.

Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

6 files changed, 4 insertions, 21 deletions

diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h
index 754995d028e2..77ebb61faf48 100644
--- a/include/linux/netfilter.h
+++ b/include/linux/netfilter.h
@@ -15,7 +15,6 @@
 #include <linux/netdevice.h>
 #include <net/net_namespace.h>
 
-#ifdef CONFIG_NETFILTER
 static inline int NF_DROP_GETERR(int verdict)
 {
 	return -(verdict >> NF_VERDICT_QBITS);
@@ -118,6 +117,7 @@ struct nf_hook_entries {
 	 */
 };
 
+#ifdef CONFIG_NETFILTER
 static inline struct nf_hook_ops **nf_hook_entries_get_hook_ops(const struct nf_hook_entries *e)
 {
 	unsigned int n = e->num_hook_entries;
diff --git a/include/linux/netfilter/x_tables.h b/include/linux/netfilter/x_tables.h
index b9bc25f57c8e..1b261c51b3a3 100644
--- a/include/linux/netfilter/x_tables.h
+++ b/include/linux/netfilter/x_tables.h
@@ -35,15 +35,12 @@ struct xt_action_param {
 	union {
 		const void *matchinfo, *targinfo;
 	};
-#if IS_ENABLED(CONFIG_NETFILTER)
 	const struct nf_hook_state *state;
-#endif
 	int fragoff;
 	unsigned int thoff;
 	bool hotdrop;
 };
 
-#if IS_ENABLED(CONFIG_NETFILTER)
 static inline struct net *xt_net(const struct xt_action_param *par)
 {
 	return par->state->net;
@@ -78,7 +75,6 @@ static inline u_int8_t xt_family(const struct xt_action_param *par)
 {
 	return par->state->pf;
 }
-#endif
 
 /**
  * struct xt_mtchk_param - parameters for match extensions'
@@ -450,9 +446,7 @@ xt_get_per_cpu_counter(struct xt_counters *cnt, unsigned int cpu)
 	return cnt;
 }
 
-#if IS_ENABLED(CONFIG_NETFILTER)
 struct nf_hook_ops *xt_hook_ops_alloc(const struct xt_table *, nf_hookfn *);
-#endif
 
 #ifdef CONFIG_COMPAT
 #include <net/compat.h>
diff --git a/include/linux/netfilter_arp/arp_tables.h b/include/linux/netfilter_arp/arp_tables.h
index 1b7b35bb9c27..e98028f00e47 100644
--- a/include/linux/netfilter_arp/arp_tables.h
+++ b/include/linux/netfilter_arp/arp_tables.h
@@ -49,7 +49,6 @@ struct arpt_error {
 }
 
 extern void *arpt_alloc_initial_table(const struct xt_table *);
-#if IS_ENABLED(CONFIG_NETFILTER)
 int arpt_register_table(struct net *net, const struct xt_table *table,
 			const struct arpt_replace *repl,
 			const struct nf_hook_ops *ops, struct xt_table **res);
@@ -58,7 +57,6 @@ void arpt_unregister_table(struct net *net, struct xt_table *table,
 extern unsigned int arpt_do_table(struct sk_buff *skb,
 				  const struct nf_hook_state *state,
 				  struct xt_table *table);
-#endif
 
 #ifdef CONFIG_COMPAT
 #include <net/compat.h>
diff --git a/include/linux/netfilter_bridge/ebtables.h b/include/linux/netfilter_bridge/ebtables.h
index b5b2d371f0ef..162f59d0d17a 100644
--- a/include/linux/netfilter_bridge/ebtables.h
+++ b/include/linux/netfilter_bridge/ebtables.h
@@ -105,7 +105,7 @@ struct ebt_table {
 
 #define EBT_ALIGN(s) (((s) + (__alignof__(struct _xt_align)-1)) & \
 		     ~(__alignof__(struct _xt_align)-1))
-#if IS_ENABLED(CONFIG_NETFILTER)
+
 extern int ebt_register_table(struct net *net,
 			      const struct ebt_table *table,
 			      const struct nf_hook_ops *ops,
@@ -115,7 +115,6 @@ extern void ebt_unregister_table(struct net *net, struct ebt_table *table,
 extern unsigned int ebt_do_table(struct sk_buff *skb,
 				 const struct nf_hook_state *state,
 				 struct ebt_table *table);
-#endif
 
 /* True if the hook mask denotes that the rule is in a base chain,
  * used in the check() functions */
diff --git a/include/linux/netfilter_ipv4/ip_tables.h b/include/linux/netfilter_ipv4/ip_tables.h
index 0b0d43ad9ed9..e9e1ed74cdf1 100644
--- a/include/linux/netfilter_ipv4/ip_tables.h
+++ b/include/linux/netfilter_ipv4/ip_tables.h
@@ -17,19 +17,16 @@
 
 #include <linux/if.h>
 #include <linux/in.h>
+#include <linux/init.h>
 #include <linux/ip.h>
 #include <linux/skbuff.h>
-
-#include <linux/init.h>
 #include <uapi/linux/netfilter_ipv4/ip_tables.h>
 
-#if IS_ENABLED(CONFIG_NETFILTER)
 int ipt_register_table(struct net *net, const struct xt_table *table,
 		       const struct ipt_replace *repl,
 		       const struct nf_hook_ops *ops, struct xt_table **res);
 void ipt_unregister_table(struct net *net, struct xt_table *table,
 			  const struct nf_hook_ops *ops);
-#endif
 
 /* Standard entry. */
 struct ipt_standard {
@@ -65,11 +62,9 @@ struct ipt_error {
 }
 
 extern void *ipt_alloc_initial_table(const struct xt_table *);
-#if IS_ENABLED(CONFIG_NETFILTER)
 extern unsigned int ipt_do_table(struct sk_buff *skb,
 				 const struct nf_hook_state *state,
 				 struct xt_table *table);
-#endif
 
 #ifdef CONFIG_COMPAT
 #include <net/compat.h>
diff --git a/include/linux/netfilter_ipv6/ip6_tables.h b/include/linux/netfilter_ipv6/ip6_tables.h
index 3a0a2bd054cc..78ab959c4575 100644
--- a/include/linux/netfilter_ipv6/ip6_tables.h
+++ b/include/linux/netfilter_ipv6/ip6_tables.h
@@ -17,15 +17,13 @@
 
 #include <linux/if.h>
 #include <linux/in6.h>
+#include <linux/init.h>
 #include <linux/ipv6.h>
 #include <linux/skbuff.h>
-
-#include <linux/init.h>
 #include <uapi/linux/netfilter_ipv6/ip6_tables.h>
 
 extern void *ip6t_alloc_initial_table(const struct xt_table *);
 
-#if IS_ENABLED(CONFIG_NETFILTER)
 int ip6t_register_table(struct net *net, const struct xt_table *table,
 			const struct ip6t_replace *repl,
 			const struct nf_hook_ops *ops, struct xt_table **res);
@@ -34,7 +32,6 @@ void ip6t_unregister_table(struct net *net, struct xt_table *table,
 extern unsigned int ip6t_do_table(struct sk_buff *skb,
 				  const struct nf_hook_state *state,
 				  struct xt_table *table);
-#endif
 
 #ifdef CONFIG_COMPAT
 #include <net/compat.h>