[svn-upgrade] Integrating new upstream version, strongswan (4.4.0)

1 files changed, 173 insertions, 0 deletions

diff --git a/src/libcharon/sa/task_manager.h b/src/libcharon/sa/task_manager.h
new file mode 100644
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+++ b/src/libcharon/sa/task_manager.h
@@ -0,0 +1,173 @@
+/*
+ * Copyright (C) 2006 Martin Willi
+ * 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 task_manager task_manager
+ * @{ @ingroup sa
+ */
+
+#ifndef TASK_MANAGER_H_
+#define TASK_MANAGER_H_
+
+typedef struct task_manager_t task_manager_t;
+
+#include <limits.h>
+
+#include <library.h>
+#include <encoding/message.h>
+#include <sa/ike_sa.h>
+#include <sa/tasks/task.h>
+
+/**
+ * First retransmit timeout in seconds.
+ */
+#define RETRANSMIT_TIMEOUT 4.0
+
+/**
+ * Base which is raised to the power of the retransmission try.
+ */
+#define RETRANSMIT_BASE 1.8
+
+/**
+ * Number of retransmits done before giving up.
+ */
+#define RETRANSMIT_TRIES 5
+
+/**
+ * Interval for mobike routability checks in ms.
+ */
+#define ROUTEABILITY_CHECK_INTERVAL 2500
+
+/**
+ * Number of routability checks before giving up
+ */
+#define ROUTEABILITY_CHECK_TRIES 10
+
+
+/**
+ * The task manager, juggles task and handles message exchanges.
+ *
+ * On incoming requests, the task manager creates new tasks on demand and
+ * juggles the request through all available tasks. Each task inspects the
+ * request and adds payloads as necessary to the response.
+ * On outgoing requests, the task manager delivers the request through the tasks
+ * to build it, the response gets processed by each task to complete.
+ * The task manager has an internal Queue to store task which should get
+ * completed.
+ * For the initial IKE_SA setup, several tasks are queued: One for the
+ * unauthenticated IKE_SA setup, one for authentication, one for CHILD_SA setup
+ * and maybe one for virtual IP assignement.
+ * The task manager is also responsible for retransmission. It uses a backoff
+ * algorithm. The timeout is calculated using
+ * RETRANSMIT_TIMEOUT * (RETRANSMIT_BASE ** try).
+ * When try reaches RETRANSMIT_TRIES, retransmission is given up.
+ *
+ * Using an initial TIMEOUT of 4s, a BASE of 1.8, and 5 TRIES gives us:
+ * @verbatim
+                   | relative | absolute
+   ---------------------------------------------------------
+   4s * (1.8 ** 0) =    4s         4s
+   4s * (1.8 ** 1) =    7s        11s
+   4s * (1.8 ** 2) =   13s        24s
+   4s * (1.8 ** 3) =   23s        47s
+   4s * (1.8 ** 4) =   42s        89s
+   4s * (1.8 ** 5) =   76s       165s
+
+   @endverbatim
+ * The peer is considered dead after 2min 45s when no reply comes in.
+ */
+struct task_manager_t {
+
+	/**
+	 * Process an incoming message.
+	 *
+	 * @param message		message to add payloads to
+	 * @return
+	 *						- DESTROY_ME if IKE_SA must be closed
+	 *						- SUCCESS otherwise
+	 */
+	status_t (*process_message) (task_manager_t *this, message_t *message);
+
+	/**
+	 * Initiate an exchange with the currently queued tasks.
+	 */
+	status_t (*initiate) (task_manager_t *this);
+
+	/**
+	 * Queue a task in the manager.
+	 *
+	 * @param task			task to queue
+	 */
+	void (*queue_task) (task_manager_t *this, task_t *task);
+
+	/**
+	 * Retransmit a request if it hasn't been acknowledged yet.
+	 *
+	 * A return value of INVALID_STATE means that the message was already
+	 * acknowledged and has not to be retransmitted. A return value of SUCCESS
+	 * means retransmission was required and the message has been resent.
+	 *
+	 * @param message_id	ID of the message to retransmit
+	 * @return
+	 *						- INVALID_STATE if retransmission not required
+	 *						- SUCCESS if retransmission sent
+	 */
+	status_t (*retransmit) (task_manager_t *this, u_int32_t message_id);
+
+	/**
+	 * Migrate all tasks from other to this.
+	 *
+	 * To rekey or reestablish an IKE_SA completely, all queued or active
+	 * tasks should get migrated to the new IKE_SA.
+	 *
+	 * @param other			manager which gives away its tasks
+	 */
+	void (*adopt_tasks) (task_manager_t *this, task_manager_t *other);
+
+	/**
+	 * Reset message ID counters of the task manager.
+	 *
+	 * The IKEv2 protocol requires to restart exchanges with message IDs
+	 * reset to zero (INVALID_KE_PAYLOAD, COOKIES, ...). The reset() method
+	 * resets the message IDs and resets all active tasks using the migrate()
+	 * method.
+	 * Use a value of UINT_MAX to keep the current message ID.
+	 *
+	 * @param initiate		message ID to initiate exchanges (send)
+	 * @param respond		message ID to respond to exchanges (expect)
+	 */
+	void (*reset) (task_manager_t *this, u_int32_t initiate, u_int32_t respond);
+
+	/**
+	 * Check if we are currently waiting for a reply.
+	 *
+	 * @return				TRUE if we are waiting, FALSE otherwise
+	 */
+	bool (*busy) (task_manager_t *this);
+
+	/**
+	 * Destroy the task_manager_t.
+	 */
+	void (*destroy) (task_manager_t *this);
+};
+
+/**
+ * Create an instance of the task manager.
+ *
+ * @param ike_sa		IKE_SA to manage.
+ */
+task_manager_t *task_manager_create(ike_sa_t *ike_sa);
+
+#endif /** TASK_MANAGER_H_ @}*/