[NETFILTER]: nf_conntrack: move extern declaration to header files

Using extern in a C file is a bad idea because the compiler can't
catch type errors.

Signed-off-by: Patrick McHardy <[e-mail]>

include/net/netfilter/ipv4/nf_conntrack_ipv4.h

···
 struct sk_buff *
 nf_ct_ipv4_ct_gather_frags(struct sk_buff *skb);
 
+extern struct nf_conntrack_l4proto nf_conntrack_l4proto_tcp4;
+extern struct nf_conntrack_l4proto nf_conntrack_l4proto_udp4;
+extern struct nf_conntrack_l4proto nf_conntrack_l4proto_icmp;
+
 #endif /*_NF_CONNTRACK_IPV4_H*/

include/net/netfilter/ipv6/nf_conntrack_ipv6.h

···
+#ifndef _NF_CONNTRACK_IPV6_H
+#define _NF_CONNTRACK_IPV6_H
+
+extern struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6;
+
+extern struct nf_conntrack_l4proto nf_conntrack_l4proto_tcp6;
+extern struct nf_conntrack_l4proto nf_conntrack_l4proto_udp6;
+extern struct nf_conntrack_l4proto nf_conntrack_l4proto_icmpv6;
+
+extern int nf_ct_ipv6_skip_exthdr(struct sk_buff *skb, int start,
+				  u8 *nexthdrp, int len);
+
+extern int nf_ct_frag6_init(void);
+extern void nf_ct_frag6_cleanup(void);
+extern struct sk_buff *nf_ct_frag6_gather(struct sk_buff *skb);
+extern void nf_ct_frag6_output(unsigned int hooknum, struct sk_buff *skb,
+			       struct net_device *in,
+			       struct net_device *out,
+			       int (*okfn)(struct sk_buff *));
+
+extern unsigned int nf_ct_frag6_timeout;
+extern unsigned int nf_ct_frag6_low_thresh;
+extern unsigned int nf_ct_frag6_high_thresh;
+
+#endif /* _NF_CONNTRACK_IPV6_H*/

include/net/netfilter/nf_conntrack.h

···
 
 
 #include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
+#include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
+
 struct nf_conn
 {
 	/* Usage count in here is 1 for hash table/destruct timer, 1 per skb,
···
 
 extern unsigned int nf_conntrack_htable_size;
 extern int nf_conntrack_checksum;
+extern atomic_t nf_conntrack_count;
+extern int nf_conntrack_max;
 
+DECLARE_PER_CPU(struct ip_conntrack_stat, nf_conntrack_stat);
 #define NF_CT_STAT_INC(count) (__get_cpu_var(nf_conntrack_stat).count++)
 
 /* no helper, no nat */

net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c

···
 #define DEBUGP(format, args...)
 #endif
 
-DECLARE_PER_CPU(struct nf_conntrack_stat, nf_conntrack_stat);
-
 static int ipv4_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff,
 			     struct nf_conntrack_tuple *tuple)
 {
···
 #endif
 	.me		 = THIS_MODULE,
 };
-
-extern struct nf_conntrack_l4proto nf_conntrack_l4proto_tcp4;
-extern struct nf_conntrack_l4proto nf_conntrack_l4proto_udp4;
-extern struct nf_conntrack_l4proto nf_conntrack_l4proto_icmp;
 
 MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET));
 MODULE_LICENSE("GPL");

net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c

···
 #define DEBUGP(format, args...)
 #endif
 
-DECLARE_PER_CPU(struct ip_conntrack_stat, nf_conntrack_stat);
-
 static int ipv6_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff,
 			     struct nf_conntrack_tuple *tuple)
 {
···
 	return nf_conntrack_confirm(pskb);
 }
 
-extern struct sk_buff *nf_ct_frag6_gather(struct sk_buff *skb);
-extern void nf_ct_frag6_output(unsigned int hooknum, struct sk_buff *skb,
-			       struct net_device *in,
-			       struct net_device *out,
-			       int (*okfn)(struct sk_buff *));
 static unsigned int ipv6_defrag(unsigned int hooknum,
 				struct sk_buff **pskb,
 				const struct net_device *in,
···
 /* From nf_conntrack_proto_icmpv6.c */
 extern unsigned int nf_ct_icmpv6_timeout;
 
-/* From nf_conntrack_reasm.c */
-extern unsigned int nf_ct_frag6_timeout;
-extern unsigned int nf_ct_frag6_low_thresh;
-extern unsigned int nf_ct_frag6_high_thresh;
-
 static struct ctl_table_header *nf_ct_ipv6_sysctl_header;
 
 static ctl_table nf_ct_sysctl_table[] = {
···
 	.get_features		= ipv6_get_features,
 	.me			= THIS_MODULE,
 };
-
-extern struct nf_conntrack_l4proto nf_conntrack_l4proto_tcp6;
-extern struct nf_conntrack_l4proto nf_conntrack_l4proto_udp6;
-extern struct nf_conntrack_l4proto nf_conntrack_l4proto_icmpv6;
-extern int nf_ct_frag6_init(void);
-extern void nf_ct_frag6_cleanup(void);
 
 MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6));
 MODULE_LICENSE("GPL");

net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c

···
 	return 1;
 }
 
-extern int
-nf_ct_ipv6_skip_exthdr(struct sk_buff *skb, int start, u8 *nexthdrp, int len);
-extern struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6;
 static int
 icmpv6_error_message(struct sk_buff *skb,
 		     unsigned int icmp6off,

net/netfilter/nf_conntrack_expect.c

···
 
 LIST_HEAD(nf_conntrack_expect_list);
 kmem_cache_t *nf_conntrack_expect_cachep __read_mostly;
-DECLARE_PER_CPU(struct ip_conntrack_stat, nf_conntrack_stat);
 static unsigned int nf_conntrack_expect_next_id;
 
 /* nf_conntrack_expect helper functions */

net/netfilter/nf_conntrack_l3proto_generic.c

···
 #define DEBUGP(format, args...)
 #endif
 
-DECLARE_PER_CPU(struct nf_conntrack_stat, nf_conntrack_stat);
-
 static int generic_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff,
 				struct nf_conntrack_tuple *tuple)
 {

net/netfilter/nf_conntrack_standalone.c

···
 
 MODULE_LICENSE("GPL");
 
-extern atomic_t nf_conntrack_count;
-DECLARE_PER_CPU(struct ip_conntrack_stat, nf_conntrack_stat);
-
 #ifdef CONFIG_PROC_FS
 int
 print_tuple(struct seq_file *s, const struct nf_conntrack_tuple *tuple,
···
 int nf_conntrack_checksum __read_mostly = 1;
 
 #ifdef CONFIG_SYSCTL
-
-/* From nf_conntrack_core.c */
-extern int nf_conntrack_max;
-extern unsigned int nf_conntrack_htable_size;
 
 /* From nf_conntrack_proto_tcp.c */
 extern unsigned int nf_ct_tcp_timeout_syn_sent;