kernel: Use a time_t to report use time in query_policy()

src/libhydra/kernel/kernel_interface.c

@@ -256,7 +256,7 @@ METHOD(kernel_interface_t, add_policy, status_t,
 METHOD(kernel_interface_t, query_policy, status_t,
 	private_kernel_interface_t *this, traffic_selector_t *src_ts,
 	traffic_selector_t *dst_ts, policy_dir_t direction, mark_t mark,
-	u_int32_t *use_time)
+	time_t *use_time)
 {
 	if (!this->ipsec)
 	{

src/libhydra/kernel/kernel_interface.h

@@ -264,14 +264,14 @@ struct kernel_interface_t {
 	 * @param dst_ts		traffic selector to match traffic dest
 	 * @param direction		direction of traffic, POLICY_(IN|OUT|FWD)
 	 * @param mark			optional mark
-	 * @param[out] use_time	the time of this SA's last use
+	 * @param[out] use_time	the (monotonic) time of this SA's last use
 	 * @return				SUCCESS if operation completed
 	 */
 	status_t (*query_policy) (kernel_interface_t *this,
 							  traffic_selector_t *src_ts,
 							  traffic_selector_t *dst_ts,
 							  policy_dir_t direction, mark_t mark,
-							  u_int32_t *use_time);
+							  time_t *use_time);
 
 	/**
 	 * Remove a policy from the SPD.

src/libhydra/kernel/kernel_ipsec.h

@@ -228,7 +228,7 @@ struct kernel_ipsec_t {
 							  traffic_selector_t *src_ts,
 							  traffic_selector_t *dst_ts,
 							  policy_dir_t direction, mark_t mark,
-							  u_int32_t *use_time);
+							  time_t *use_time);
 
 	/**
 	 * Remove a policy from the SPD.