implemented RADIUS Filter-ID attribute

src/libradius/radius_message.h

@@ -30,6 +30,8 @@
 
 #define MAX_RADIUS_ATTRIBUTE_SIZE	253
 
+#define RADIUS_TUNNEL_TYPE_ESP		9
+
 typedef struct radius_message_t radius_message_t;
 typedef enum radius_message_code_t radius_message_code_t;
 typedef enum radius_attribute_type_t radius_attribute_type_t;