--- /dev/null
+/*
+ * Copyright (C) 2010 Tobias Brunner
+ * Hochschule fuer Technik Rapperswil
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+/**
+ * @defgroup kernel_listener kernel_listener
+ * @{ @ingroup kernel
+ */
+
+#ifndef KERNEL_LISTENER_H_
+#define KERNEL_LISTENER_H_
+
+typedef struct kernel_listener_t kernel_listener_t;
+
+#include <kernel/kernel_ipsec.h>
+#include <selectors/traffic_selector.h>
+#include <utils/host.h>
+
+/**
+ * Interface for components interested in kernel events.
+ */
+struct kernel_listener_t {
+
+ /**
+ * Hook called if an acquire event for a policy is received.
+ *
+ * @param reqid reqid of the policy to acquire
+ * @param src_ts source traffic selector
+ * @param dst_ts destination traffic selector
+ * @return TRUE to remain registered, FALSE to unregister
+ */
+ bool (*acquire)(kernel_listener_t *this, u_int32_t reqid,
+ traffic_selector_t *src_ts, traffic_selector_t *dst_ts);
+
+ /**
+ * Hook called if an exire event for an IPsec SA is received.
+ *
+ * @param reqid reqid of the expired SA
+ * @param protocol protocol of the expired SA
+ * @param spi spi of the expired SA
+ * @param hard TRUE if it is a hard expire, FALSE otherwise
+ * @return TRUE to remain registered, FALSE to unregister
+ */
+ bool (*expire)(kernel_listener_t *this, u_int32_t reqid,
+ protocol_id_t protocol, u_int32_t spi, bool hard);
+
+ /**
+ * Hook called if the NAT mappings of an IPsec SA changed.
+ *
+ * @param reqid reqid of the SA
+ * @param spi spi of the SA
+ * @param remote new remote host
+ * @return TRUE to remain registered, FALSE to unregister
+ */
+ bool (*mapping)(kernel_listener_t *this, u_int32_t reqid, u_int32_t spi,
+ host_t *remote);
+
+ /**
+ * Hook called if a migrate event for a policy is received.
+ *
+ * @param reqid reqid of the policy
+ * @param src_ts source traffic selector
+ * @param dst_ts destination traffic selector
+ * @param direction direction of the policy (in|out)
+ * @param local local host address to be used in the IKE_SA
+ * @param remote remote host address to be used in the IKE_SA
+ * @return TRUE to remain registered, FALSE to unregister
+ */
+ bool (*migrate)(kernel_listener_t *this, u_int32_t reqid,
+ traffic_selector_t *src_ts, traffic_selector_t *dst_ts,
+ policy_dir_t direction, host_t *local, host_t *remote);
+
+ /**
+ * Hook called if changes in the networking layer occured (interfaces
+ * up/down, routes added/deleted etc.).
+ *
+ * @param address TRUE if address list, FALSE if routing changed
+ * @return TRUE to remain registered, FALSE to unregister
+ */
+ bool (*roam)(kernel_listener_t *this, bool address);
+};
+
+#endif /** KERNEL_LISTENER_H_ @}*/