first merge of NATT code

src/charon/config/configuration.h

@@ -69,6 +69,39 @@ struct configuration_t {
 	 */	
 	u_int32_t (*get_half_open_ike_sa_timeout) (configuration_t *this);
 
+	/**
+	 * @brief Returns the keepalive interval in ms.
+	 * 
+	 * The keepalive interval defines the idle time after which a
+	 * NAT keepalive packet should be sent.
+	 * 
+	 * @param this				calling object
+	 * @return					interval in milliseconds (ms)
+	 */	
+	u_int32_t (*get_keepalive_interval) (configuration_t *this);
+
+	/**
+	 * @brief Returns the keepalive timeout in ms.
+	 * 
+	 * The keepalive timeout defines how long we should keep sending
+	 * NAT keepalives after closing an IKE_SA.
+	 * 
+	 * @param this				calling object
+	 * @return					timeout in milliseconds (ms)
+	 */	
+	u_int32_t (*get_keepalive_timeout) (configuration_t *this);
+
+	/**
+	 * @brief Returns the DPD interval in ms.
+	 * 
+	 * The DPD interval defines the time after which a
+	 * DPD request packet should be sent.
+	 * 
+	 * @param this				calling object
+	 * @return					interval in milliseconds (ms)
+	 */	
+	u_int32_t (*get_dpd_interval) (configuration_t *this);
+
 	/**
 	 * @brief Destroys a configuration_t object.
 	 *