diff --git a/src/internal.h b/src/internal.h
index 3a88d1a..cd2093a 100644
--- a/src/internal.h
+++ b/src/internal.h
@@ -9,4 +9,15 @@
 #	define EXPORT_SYMBOL
 #endif
 
+#include <stdint.h>
+#include <netinet/in.h>
+
+struct gtp_tunnel {
+	uint32_t	ifidx;
+	struct in_addr	ms_addr;
+	struct in_addr	sgsn_addr;
+	uint64_t	tid;
+	int		gtp_version;
+};
+
 #endif