+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;
+
+extern int nf_conntrack_ipv4_compat_init(void);
+extern void nf_conntrack_ipv4_compat_fini(void);
+