Imported Upstream version 5.0.1

1 files changed, 1714 insertions, 0 deletions

diff --git a/src/libcharon/sa/ikev1/task_manager_v1.c b/src/libcharon/sa/ikev1/task_manager_v1.c
new file mode 100644
index 000000000..fd0ad235a
--- /dev/null
+++ b/src/libcharon/sa/ikev1/task_manager_v1.c
@@ -0,0 +1,1714 @@
+/*
+ * Copyright (C) 2007-2011 Tobias Brunner
+ * Copyright (C) 2007-2011 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.
+ */
+
+#include "task_manager_v1.h"
+
+#include <math.h>
+
+#include <daemon.h>
+#include <sa/ikev1/tasks/main_mode.h>
+#include <sa/ikev1/tasks/aggressive_mode.h>
+#include <sa/ikev1/tasks/quick_mode.h>
+#include <sa/ikev1/tasks/quick_delete.h>
+#include <sa/ikev1/tasks/xauth.h>
+#include <sa/ikev1/tasks/mode_config.h>
+#include <sa/ikev1/tasks/informational.h>
+#include <sa/ikev1/tasks/isakmp_natd.h>
+#include <sa/ikev1/tasks/isakmp_vendor.h>
+#include <sa/ikev1/tasks/isakmp_cert_pre.h>
+#include <sa/ikev1/tasks/isakmp_cert_post.h>
+#include <sa/ikev1/tasks/isakmp_delete.h>
+#include <sa/ikev1/tasks/isakmp_dpd.h>
+
+#include <processing/jobs/retransmit_job.h>
+#include <processing/jobs/delete_ike_sa_job.h>
+#include <processing/jobs/dpd_timeout_job.h>
+
+/**
+ * Number of old messages hashes we keep for retransmission.
+ *
+ * In Main Mode, we must ignore messages from a previous message pair if
+ * we already continued to the next. Otherwise a late retransmission
+ * could be considered as a reply to the newer request.
+ */
+#define MAX_OLD_HASHES 2
+
+/**
+ * First sequence number of responding packets.
+ *
+ * To distinguish retransmission jobs for initiating and responding packets,
+ * we split up the sequence counter and use the upper half for responding.
+ */
+#define RESPONDING_SEQ INT_MAX
+
+typedef struct exchange_t exchange_t;
+
+/**
+ * An exchange in the air, used do detect and handle retransmission
+ */
+struct exchange_t {
+
+	/**
+	 * Message ID used for this transaction
+	 */
+	u_int32_t mid;
+
+	/**
+	 * generated packet for retransmission
+	 */
+	packet_t *packet;
+};
+
+typedef struct private_task_manager_t private_task_manager_t;
+
+/**
+ * private data of the task manager
+ */
+struct private_task_manager_t {
+
+	/**
+	 * public functions
+	 */
+	task_manager_v1_t public;
+
+	/**
+	 * associated IKE_SA we are serving
+	 */
+	ike_sa_t *ike_sa;
+
+	/**
+	 * RNG to create message IDs
+	 */
+	rng_t *rng;
+
+	/**
+	 * Exchange we are currently handling as responder
+	 */
+	struct {
+		/**
+		 * Message ID of the last response
+		 */
+		u_int32_t mid;
+
+		/**
+		 * Hash of a previously received message
+		 */
+		u_int32_t hash;
+
+		/**
+		 * packet for retransmission
+		 */
+		packet_t *packet;
+
+		/**
+		 * Sequence number of the last sent message
+		 */
+		u_int32_t seqnr;
+
+		/**
+		 * how many times we have retransmitted so far
+		 */
+		u_int retransmitted;
+
+	} responding;
+
+	/**
+	 * Exchange we are currently handling as initiator
+	 */
+	struct {
+		/**
+		 * Message ID of the exchange
+		 */
+		u_int32_t mid;
+
+		/**
+		 * Hashes of old responses we can ignore
+		 */
+		u_int32_t old_hashes[MAX_OLD_HASHES];
+
+		/**
+		 * Position in old hash array
+		 */
+		int old_hash_pos;
+
+		/**
+		 * Sequence number of the last sent message
+		 */
+		u_int32_t seqnr;
+
+		/**
+		 * how many times we have retransmitted so far
+		 */
+		u_int retransmitted;
+
+		/**
+		 * packet for retransmission
+		 */
+		packet_t *packet;
+
+		/**
+		 * type of the initated exchange
+		 */
+		exchange_type_t type;
+
+	} initiating;
+
+	/**
+	 * List of queued tasks not yet in action
+	 */
+	linked_list_t *queued_tasks;
+
+	/**
+	 * List of active tasks, initiated by ourselve
+	 */
+	linked_list_t *active_tasks;
+
+	/**
+	 * List of tasks initiated by peer
+	 */
+	linked_list_t *passive_tasks;
+
+	/**
+	 * Queued messages not yet ready to process
+	 */
+	message_t *queued;
+
+	/**
+	 * Number of times we retransmit messages before giving up
+	 */
+	u_int retransmit_tries;
+
+	/**
+	 * Retransmission timeout
+	 */
+	double retransmit_timeout;
+
+	/**
+	 * Base to calculate retransmission timeout
+	 */
+	double retransmit_base;
+
+	/**
+	 * Sequence number for sending DPD requests
+	 */
+	u_int32_t dpd_send;
+
+	/**
+	 * Sequence number for received DPD requests
+	 */
+	u_int32_t dpd_recv;
+};
+
+METHOD(task_manager_t, flush_queue, void,
+	private_task_manager_t *this, task_queue_t queue)
+{
+	linked_list_t *list;
+	task_t *task;
+
+	if (this->queued)
+	{
+		this->queued->destroy(this->queued);
+		this->queued = NULL;
+	}
+	switch (queue)
+	{
+		case TASK_QUEUE_ACTIVE:
+			list = this->active_tasks;
+			/* cancel pending retransmits */
+			this->initiating.type = EXCHANGE_TYPE_UNDEFINED;
+			DESTROY_IF(this->initiating.packet);
+			this->initiating.packet = NULL;
+			break;
+		case TASK_QUEUE_PASSIVE:
+			list = this->passive_tasks;
+			break;
+		case TASK_QUEUE_QUEUED:
+			list = this->queued_tasks;
+			break;
+		default:
+			return;
+	}
+	while (list->remove_last(list, (void**)&task) == SUCCESS)
+	{
+		task->destroy(task);
+	}
+}
+
+/**
+ * flush all tasks in the task manager
+ */
+static void flush(private_task_manager_t *this)
+{
+	flush_queue(this, TASK_QUEUE_QUEUED);
+	flush_queue(this, TASK_QUEUE_PASSIVE);
+	flush_queue(this, TASK_QUEUE_ACTIVE);
+}
+
+/**
+ * move a task of a specific type from the queue to the active list
+ */
+static bool activate_task(private_task_manager_t *this, task_type_t type)
+{
+	enumerator_t *enumerator;
+	task_t *task;
+	bool found = FALSE;
+
+	enumerator = this->queued_tasks->create_enumerator(this->queued_tasks);
+	while (enumerator->enumerate(enumerator, (void**)&task))
+	{
+		if (task->get_type(task) == type)
+		{
+			DBG2(DBG_IKE, "  activating %N task", task_type_names, type);
+			this->queued_tasks->remove_at(this->queued_tasks, enumerator);
+			this->active_tasks->insert_last(this->active_tasks, task);
+			found = TRUE;
+			break;
+		}
+	}
+	enumerator->destroy(enumerator);
+	return found;
+}
+
+/**
+ * Retransmit a packet, either as initiator or as responder
+ */
+static status_t retransmit_packet(private_task_manager_t *this, u_int32_t seqnr,
+							u_int mid, u_int retransmitted, packet_t *packet)
+{
+	u_int32_t t;
+
+	if (retransmitted > this->retransmit_tries)
+	{
+		DBG1(DBG_IKE, "giving up after %u retransmits", retransmitted - 1);
+		return DESTROY_ME;
+	}
+	t = (u_int32_t)(this->retransmit_timeout * 1000.0 *
+					pow(this->retransmit_base, retransmitted));
+	if (retransmitted)
+	{
+		DBG1(DBG_IKE, "sending retransmit %u of %s message ID %u, seq %u",
+			 retransmitted, seqnr < RESPONDING_SEQ ? "request" : "response",
+			 mid, seqnr < RESPONDING_SEQ ? seqnr : seqnr - RESPONDING_SEQ);
+	}
+	charon->sender->send(charon->sender, packet->clone(packet));
+	lib->scheduler->schedule_job_ms(lib->scheduler, (job_t*)
+			retransmit_job_create(seqnr, this->ike_sa->get_id(this->ike_sa)), t);
+	return NEED_MORE;
+}
+
+METHOD(task_manager_t, retransmit, status_t,
+	private_task_manager_t *this, u_int32_t seqnr)
+{
+	status_t status = SUCCESS;
+
+	if (seqnr == this->initiating.seqnr && this->initiating.packet)
+	{
+		status = retransmit_packet(this, seqnr, this->initiating.mid,
+					this->initiating.retransmitted, this->initiating.packet);
+		if (status == NEED_MORE)
+		{
+			this->initiating.retransmitted++;
+			status = SUCCESS;
+		}
+	}
+	if (seqnr == this->responding.seqnr && this->responding.packet)
+	{
+		status = retransmit_packet(this, seqnr, this->responding.mid,
+					this->responding.retransmitted, this->responding.packet);
+		if (status == NEED_MORE)
+		{
+			this->responding.retransmitted++;
+			status = SUCCESS;
+		}
+	}
+	return status;
+}
+
+/**
+ * Check if we have to wait for a mode config before starting a quick mode
+ */
+static bool mode_config_expected(private_task_manager_t *this)
+{
+	enumerator_t *enumerator;
+	peer_cfg_t *peer_cfg;
+	char *pool;
+	host_t *host;
+
+	peer_cfg = this->ike_sa->get_peer_cfg(this->ike_sa);
+	if (peer_cfg)
+	{
+		enumerator = peer_cfg->create_pool_enumerator(peer_cfg);
+		if (!enumerator->enumerate(enumerator, &pool))
+		{	/* no pool configured */
+			enumerator->destroy(enumerator);
+			return FALSE;
+		}
+		enumerator->destroy(enumerator);
+
+		enumerator = this->ike_sa->create_virtual_ip_enumerator(this->ike_sa,
+																FALSE);
+		if (!enumerator->enumerate(enumerator, &host))
+		{	/* have a pool, but no VIP assigned yet */
+			enumerator->destroy(enumerator);
+			return TRUE;
+		}
+		enumerator->destroy(enumerator);
+	}
+	return FALSE;
+}
+
+METHOD(task_manager_t, initiate, status_t,
+	private_task_manager_t *this)
+{
+	enumerator_t *enumerator;
+	task_t *task;
+	message_t *message;
+	host_t *me, *other;
+	status_t status;
+	exchange_type_t exchange = EXCHANGE_TYPE_UNDEFINED;
+	bool new_mid = FALSE, expect_response = FALSE, cancelled = FALSE, keep = FALSE;
+
+	if (this->initiating.type != EXCHANGE_TYPE_UNDEFINED &&
+		this->initiating.type != INFORMATIONAL_V1)
+	{
+		DBG2(DBG_IKE, "delaying task initiation, %N exchange in progress",
+				exchange_type_names, this->initiating.type);
+		/* do not initiate if we already have a message in the air */
+		return SUCCESS;
+	}
+
+	if (this->active_tasks->get_count(this->active_tasks) == 0)
+	{
+		DBG2(DBG_IKE, "activating new tasks");
+		switch (this->ike_sa->get_state(this->ike_sa))
+		{
+			case IKE_CREATED:
+				activate_task(this, TASK_ISAKMP_VENDOR);
+				activate_task(this, TASK_ISAKMP_CERT_PRE);
+				if (activate_task(this, TASK_MAIN_MODE))
+				{
+					exchange = ID_PROT;
+				}
+				else if (activate_task(this, TASK_AGGRESSIVE_MODE))
+				{
+					exchange = AGGRESSIVE;
+				}
+				activate_task(this, TASK_ISAKMP_CERT_POST);
+				activate_task(this, TASK_ISAKMP_NATD);
+				break;
+			case IKE_CONNECTING:
+				if (activate_task(this, TASK_ISAKMP_DELETE))
+				{
+					exchange = INFORMATIONAL_V1;
+					new_mid = TRUE;
+					break;
+				}
+				if (activate_task(this, TASK_XAUTH))
+				{
+					exchange = TRANSACTION;
+					new_mid = TRUE;
+					break;
+				}
+				if (activate_task(this, TASK_INFORMATIONAL))
+				{
+					exchange = INFORMATIONAL_V1;
+					new_mid = TRUE;
+					break;
+				}
+				break;
+			case IKE_ESTABLISHED:
+				if (activate_task(this, TASK_MODE_CONFIG))
+				{
+					exchange = TRANSACTION;
+					new_mid = TRUE;
+					break;
+				}
+				if (!mode_config_expected(this) &&
+					activate_task(this, TASK_QUICK_MODE))
+				{
+					exchange = QUICK_MODE;
+					new_mid = TRUE;
+					break;
+				}
+				if (activate_task(this, TASK_INFORMATIONAL))
+				{
+					exchange = INFORMATIONAL_V1;
+					new_mid = TRUE;
+					break;
+				}
+				if (activate_task(this, TASK_QUICK_DELETE))
+				{
+					exchange = INFORMATIONAL_V1;
+					new_mid = TRUE;
+					break;
+				}
+				if (activate_task(this, TASK_ISAKMP_DELETE))
+				{
+					exchange = INFORMATIONAL_V1;
+					new_mid = TRUE;
+					break;
+				}
+				if (activate_task(this, TASK_ISAKMP_DPD))
+				{
+					exchange = INFORMATIONAL_V1;
+					new_mid = TRUE;
+					break;
+				}
+				break;
+			default:
+				break;
+		}
+	}
+	else
+	{
+		DBG2(DBG_IKE, "reinitiating already active tasks");
+		enumerator = this->active_tasks->create_enumerator(this->active_tasks);
+		while (enumerator->enumerate(enumerator, (void**)&task))
+		{
+			DBG2(DBG_IKE, "  %N task", task_type_names, task->get_type(task));
+			switch (task->get_type(task))
+			{
+				case TASK_MAIN_MODE:
+					exchange = ID_PROT;
+					break;
+				case TASK_AGGRESSIVE_MODE:
+					exchange = AGGRESSIVE;
+					break;
+				case TASK_QUICK_MODE:
+					exchange = QUICK_MODE;
+					break;
+				case TASK_XAUTH:
+					exchange = TRANSACTION;
+					new_mid = TRUE;
+					break;
+				default:
+					continue;
+			}
+			break;
+		}
+		enumerator->destroy(enumerator);
+	}
+
+	if (exchange == EXCHANGE_TYPE_UNDEFINED)
+	{
+		DBG2(DBG_IKE, "nothing to initiate");
+		/* nothing to do yet... */
+		return SUCCESS;
+	}
+
+	me = this->ike_sa->get_my_host(this->ike_sa);
+	other = this->ike_sa->get_other_host(this->ike_sa);
+
+	if (new_mid)
+	{
+		if (!this->rng->get_bytes(this->rng, sizeof(this->initiating.mid),
+								 (void*)&this->initiating.mid))
+		{
+			DBG1(DBG_IKE, "failed to allocate message ID, destroying IKE_SA");
+			flush(this);
+			return DESTROY_ME;
+		}
+	}
+	message = message_create(IKEV1_MAJOR_VERSION, IKEV1_MINOR_VERSION);
+	message->set_message_id(message, this->initiating.mid);
+	message->set_source(message, me->clone(me));
+	message->set_destination(message, other->clone(other));
+	message->set_exchange_type(message, exchange);
+	this->initiating.type = exchange;
+	this->initiating.retransmitted = 0;
+
+	enumerator = this->active_tasks->create_enumerator(this->active_tasks);
+	while (enumerator->enumerate(enumerator, (void*)&task))
+	{
+		switch (task->build(task, message))
+		{
+			case SUCCESS:
+				/* task completed, remove it */
+				this->active_tasks->remove_at(this->active_tasks, enumerator);
+				if (task->get_type(task) == TASK_AGGRESSIVE_MODE ||
+					task->get_type(task) == TASK_QUICK_MODE)
+				{	/* last message of three message exchange */
+					keep = TRUE;
+				}
+				task->destroy(task);
+				continue;
+			case NEED_MORE:
+				expect_response = TRUE;
+				/* processed, but task needs another exchange */
+				continue;
+			case ALREADY_DONE:
+				cancelled = TRUE;
+				break;
+			case FAILED:
+			default:
+				if (this->ike_sa->get_state(this->ike_sa) != IKE_CONNECTING)
+				{
+					charon->bus->ike_updown(charon->bus, this->ike_sa, FALSE);
+				}
+				/* FALL */
+			case DESTROY_ME:
+				/* critical failure, destroy IKE_SA */
+				enumerator->destroy(enumerator);
+				message->destroy(message);
+				flush(this);
+				return DESTROY_ME;
+		}
+		break;
+	}
+	enumerator->destroy(enumerator);
+
+	if (this->active_tasks->get_count(this->active_tasks) == 0 &&
+		(exchange == QUICK_MODE || exchange == AGGRESSIVE))
+	{	/* tasks completed, no exchange active anymore */
+		this->initiating.type = EXCHANGE_TYPE_UNDEFINED;
+	}
+	if (cancelled)
+	{
+		message->destroy(message);
+		return initiate(this);
+	}
+
+	DESTROY_IF(this->initiating.packet);
+	status = this->ike_sa->generate_message(this->ike_sa, message,
+											&this->initiating.packet);
+	if (status != SUCCESS)
+	{
+		/* message generation failed. There is nothing more to do than to
+		 * close the SA */
+		message->destroy(message);
+		flush(this);
+		charon->bus->ike_updown(charon->bus, this->ike_sa, FALSE);
+		return DESTROY_ME;
+	}
+
+	this->initiating.seqnr++;
+	if (expect_response)
+	{
+		message->destroy(message);
+		return retransmit(this, this->initiating.seqnr);
+	}
+	if (keep)
+	{	/* keep the packet for retransmission, the responder might request it */
+		charon->sender->send(charon->sender,
+					this->initiating.packet->clone(this->initiating.packet));
+	}
+	else
+	{
+		charon->sender->send(charon->sender, this->initiating.packet);
+		this->initiating.packet = NULL;
+	}
+	message->destroy(message);
+
+	if (exchange == INFORMATIONAL_V1)
+	{
+		switch (this->ike_sa->get_state(this->ike_sa))
+		{
+			case IKE_CONNECTING:
+				/* close after sending an INFORMATIONAL when unestablished */
+				return FAILED;
+			case IKE_DELETING:
+				/* close after sending a DELETE */
+				return DESTROY_ME;
+			default:
+				break;
+		}
+	}
+	return initiate(this);
+}
+
+/**
+ * build a response depending on the "passive" task list
+ */
+static status_t build_response(private_task_manager_t *this, message_t *request)
+{
+	enumerator_t *enumerator;
+	task_t *task;
+	message_t *message;
+	host_t *me, *other;
+	bool delete = FALSE, cancelled = FALSE, expect_request = FALSE;
+	status_t status;
+
+	me = request->get_destination(request);
+	other = request->get_source(request);
+
+	message = message_create(IKEV1_MAJOR_VERSION, IKEV1_MINOR_VERSION);
+	message->set_exchange_type(message, request->get_exchange_type(request));
+	/* send response along the path the request came in */
+	message->set_source(message, me->clone(me));
+	message->set_destination(message, other->clone(other));
+	message->set_message_id(message, request->get_message_id(request));
+	message->set_request(message, FALSE);
+
+	this->responding.mid = request->get_message_id(request);
+	this->responding.retransmitted = 0;
+	this->responding.seqnr++;
+
+	enumerator = this->passive_tasks->create_enumerator(this->passive_tasks);
+	while (enumerator->enumerate(enumerator, (void*)&task))
+	{
+		switch (task->build(task, message))
+		{
+			case SUCCESS:
+				/* task completed, remove it */
+				this->passive_tasks->remove_at(this->passive_tasks, enumerator);
+				task->destroy(task);
+				continue;
+			case NEED_MORE:
+				/* processed, but task needs another exchange */
+				if (task->get_type(task) == TASK_QUICK_MODE ||
+					task->get_type(task) == TASK_AGGRESSIVE_MODE)
+				{	/* we rely on initiator retransmission, except for
+					 * three-message exchanges */
+					expect_request = TRUE;
+				}
+				continue;
+			case ALREADY_DONE:
+				cancelled = TRUE;
+				break;
+			case FAILED:
+			default:
+				charon->bus->ike_updown(charon->bus, this->ike_sa, FALSE);
+				/* FALL */
+			case DESTROY_ME:
+				/* destroy IKE_SA, but SEND response first */
+				delete = TRUE;
+				break;
+		}
+		break;
+	}
+	enumerator->destroy(enumerator);
+
+	DESTROY_IF(this->responding.packet);
+	this->responding.packet = NULL;
+	if (cancelled)
+	{
+		message->destroy(message);
+		return initiate(this);
+	}
+	status = this->ike_sa->generate_message(this->ike_sa, message,
+											&this->responding.packet);
+	message->destroy(message);
+	if (status != SUCCESS)
+	{
+		charon->bus->ike_updown(charon->bus, this->ike_sa, FALSE);
+		return DESTROY_ME;
+	}
+
+	if (expect_request && !delete)
+	{
+		return retransmit(this, this->responding.seqnr);
+	}
+	charon->sender->send(charon->sender,
+					this->responding.packet->clone(this->responding.packet));
+	if (delete)
+	{
+		return DESTROY_ME;
+	}
+	return SUCCESS;
+}
+
+/**
+ * Send a notify in a separate INFORMATIONAL exchange back to the sender.
+ * The notify protocol_id is set to ISAKMP
+ */
+static void send_notify(private_task_manager_t *this, message_t *request,
+						notify_type_t type)
+{
+	message_t *response;
+	packet_t *packet;
+	host_t *me, *other;
+	u_int32_t mid;
+
+	if (request->get_exchange_type(request) == INFORMATIONAL_V1)
+	{	/* don't respond to INFORMATIONAL requests to avoid a notify war */
+		DBG1(DBG_IKE, "ignore malformed INFORMATIONAL request");
+		return;
+	}
+	if (!this->rng->get_bytes(this->rng, sizeof(mid), (void*)&mid))
+	{
+		DBG1(DBG_IKE, "failed to allocate message ID");
+		return;
+	}
+	response = message_create(IKEV1_MAJOR_VERSION, IKEV1_MINOR_VERSION);
+	response->set_exchange_type(response, INFORMATIONAL_V1);
+	response->set_request(response, TRUE);
+	response->set_message_id(response, mid);
+	response->add_payload(response, (payload_t*)
+				notify_payload_create_from_protocol_and_type(NOTIFY_V1,
+													PROTO_IKE, type));
+
+	me = this->ike_sa->get_my_host(this->ike_sa);
+	if (me->is_anyaddr(me))
+	{
+		me = request->get_destination(request);
+		this->ike_sa->set_my_host(this->ike_sa, me->clone(me));
+	}
+	other = this->ike_sa->get_other_host(this->ike_sa);
+	if (other->is_anyaddr(other))
+	{
+		other = request->get_source(request);
+		this->ike_sa->set_other_host(this->ike_sa, other->clone(other));
+	}
+	response->set_source(response, me->clone(me));
+	response->set_destination(response, other->clone(other));
+	if (this->ike_sa->generate_message(this->ike_sa, response,
+									   &packet) == SUCCESS)
+	{
+		charon->sender->send(charon->sender, packet);
+	}
+	response->destroy(response);
+}
+
+/**
+ * Process a DPD request/response
+ */
+static bool process_dpd(private_task_manager_t *this, message_t *message)
+{
+	notify_payload_t *notify;
+	notify_type_t type;
+	u_int32_t seq;
+	chunk_t data;
+
+	type = DPD_R_U_THERE;
+	notify = message->get_notify(message, type);
+	if (!notify)
+	{
+		type = DPD_R_U_THERE_ACK;
+		notify = message->get_notify(message, type);
+	}
+	if (!notify)
+	{
+		return FALSE;
+	}
+	data = notify->get_notification_data(notify);
+	if (data.len != 4)
+	{
+		return FALSE;
+	}
+	seq = untoh32(data.ptr);
+
+	if (type == DPD_R_U_THERE)
+	{
+		if (this->dpd_recv == 0 || seq == this->dpd_recv)
+		{	/* check sequence validity */
+			this->dpd_recv = seq + 1;
+			this->ike_sa->set_statistic(this->ike_sa, STAT_INBOUND,
+										time_monotonic(NULL));
+		}
+		/* but respond anyway */
+		this->ike_sa->queue_task(this->ike_sa,
+				&isakmp_dpd_create(this->ike_sa, DPD_R_U_THERE_ACK, seq)->task);
+	}
+	else /* DPD_R_U_THERE_ACK */
+	{
+		if (seq == this->dpd_send - 1)
+		{
+			this->ike_sa->set_statistic(this->ike_sa, STAT_INBOUND,
+										time_monotonic(NULL));
+		}
+		else
+		{
+			DBG1(DBG_IKE, "received invalid DPD sequence number %u "
+				 "(expected %u), ignored", seq, this->dpd_send - 1);
+		}
+	}
+	return TRUE;
+}
+
+/**
+ * handle an incoming request message
+ */
+static status_t process_request(private_task_manager_t *this,
+								message_t *message)
+{
+	enumerator_t *enumerator;
+	task_t *task = NULL;
+	bool send_response = FALSE, dpd = FALSE;
+
+	if (message->get_exchange_type(message) == INFORMATIONAL_V1 ||
+		this->passive_tasks->get_count(this->passive_tasks) == 0)
+	{	/* create tasks depending on request type, if not already some queued */
+		switch (message->get_exchange_type(message))
+		{
+			case ID_PROT:
+				task = (task_t *)isakmp_vendor_create(this->ike_sa, FALSE);
+				this->passive_tasks->insert_last(this->passive_tasks, task);
+				task = (task_t*)isakmp_cert_pre_create(this->ike_sa, FALSE);
+				this->passive_tasks->insert_last(this->passive_tasks, task);
+				task = (task_t *)main_mode_create(this->ike_sa, FALSE);
+				this->passive_tasks->insert_last(this->passive_tasks, task);
+				task = (task_t*)isakmp_cert_post_create(this->ike_sa, FALSE);
+				this->passive_tasks->insert_last(this->passive_tasks, task);
+				task = (task_t *)isakmp_natd_create(this->ike_sa, FALSE);
+				this->passive_tasks->insert_last(this->passive_tasks, task);
+				break;
+			case AGGRESSIVE:
+				task = (task_t *)isakmp_vendor_create(this->ike_sa, FALSE);
+				this->passive_tasks->insert_last(this->passive_tasks, task);
+				task = (task_t*)isakmp_cert_pre_create(this->ike_sa, FALSE);
+				this->passive_tasks->insert_last(this->passive_tasks, task);
+				task = (task_t *)aggressive_mode_create(this->ike_sa, FALSE);
+				this->passive_tasks->insert_last(this->passive_tasks, task);
+				task = (task_t*)isakmp_cert_post_create(this->ike_sa, FALSE);
+				this->passive_tasks->insert_last(this->passive_tasks, task);
+				task = (task_t *)isakmp_natd_create(this->ike_sa, FALSE);
+				this->passive_tasks->insert_last(this->passive_tasks, task);
+				break;
+			case QUICK_MODE:
+				if (this->ike_sa->get_state(this->ike_sa) != IKE_ESTABLISHED)
+				{
+					DBG1(DBG_IKE, "received quick mode request for "
+						 "unestablished IKE_SA, ignored");
+					return FAILED;
+				}
+				task = (task_t *)quick_mode_create(this->ike_sa, NULL,
+												   NULL, NULL);
+				this->passive_tasks->insert_last(this->passive_tasks, task);
+				break;
+			case INFORMATIONAL_V1:
+				if (process_dpd(this, message))
+				{
+					dpd = TRUE;
+				}
+				else
+				{
+					task = (task_t *)informational_create(this->ike_sa, NULL);
+					this->passive_tasks->insert_first(this->passive_tasks, task);
+				}
+				break;
+			case TRANSACTION:
+				if (this->ike_sa->get_state(this->ike_sa) != IKE_CONNECTING)
+				{
+					task = (task_t *)mode_config_create(this->ike_sa, FALSE);
+				}
+				else
+				{
+					task = (task_t *)xauth_create(this->ike_sa, FALSE);
+				}
+				this->passive_tasks->insert_last(this->passive_tasks, task);
+				break;
+			default:
+				return FAILED;
+		}
+	}
+	if (dpd)
+	{
+		return initiate(this);
+	}
+	this->ike_sa->set_statistic(this->ike_sa, STAT_INBOUND, time_monotonic(NULL));
+
+	/* let the tasks process the message */
+	enumerator = this->passive_tasks->create_enumerator(this->passive_tasks);
+	while (enumerator->enumerate(enumerator, (void*)&task))
+	{
+		switch (task->process(task, message))
+		{
+			case SUCCESS:
+				/* task completed, remove it */
+				this->passive_tasks->remove_at(this->passive_tasks, enumerator);
+				task->destroy(task);
+				continue;
+			case NEED_MORE:
+				/* processed, but task needs at least another call to build() */
+				send_response = TRUE;
+				continue;
+			case ALREADY_DONE:
+				send_response = FALSE;
+				break;
+			case FAILED:
+			default:
+				charon->bus->ike_updown(charon->bus, this->ike_sa, FALSE);
+				/* FALL */
+			case DESTROY_ME:
+				/* critical failure, destroy IKE_SA */
+				this->passive_tasks->remove_at(this->passive_tasks, enumerator);
+				enumerator->destroy(enumerator);
+				task->destroy(task);
+				return DESTROY_ME;
+		}
+		break;
+	}
+	enumerator->destroy(enumerator);
+
+	if (send_response)
+	{
+		if (build_response(this, message) != SUCCESS)
+		{
+			return DESTROY_ME;
+		}
+	}
+	else
+	{	/* We don't send a response, so don't retransmit one if we get
+		 * the same message again. */
+		DESTROY_IF(this->responding.packet);
+		this->responding.packet = NULL;
+	}
+	if (this->passive_tasks->get_count(this->passive_tasks) == 0 &&
+		this->queued_tasks->get_count(this->queued_tasks) > 0)
+	{
+		/* passive tasks completed, check if an active task has been queued,
+		 * such as XAUTH or modeconfig push */
+		return initiate(this);
+	}
+	return SUCCESS;
+}
+
+/**
+ * handle an incoming response message
+ */
+static status_t process_response(private_task_manager_t *this,
+								 message_t *message)
+{
+	enumerator_t *enumerator;
+	message_t *queued;
+	status_t status;
+	task_t *task;
+
+	if (message->get_exchange_type(message) != this->initiating.type)
+	{
+		DBG1(DBG_IKE, "received %N response, but expected %N",
+			 exchange_type_names, message->get_exchange_type(message),
+			 exchange_type_names, this->initiating.type);
+		charon->bus->ike_updown(charon->bus, this->ike_sa, FALSE);
+		return DESTROY_ME;
+	}
+
+	enumerator = this->active_tasks->create_enumerator(this->active_tasks);
+	while (enumerator->enumerate(enumerator, (void*)&task))
+	{
+		switch (task->process(task, message))
+		{
+			case SUCCESS:
+				/* task completed, remove it */
+				this->active_tasks->remove_at(this->active_tasks, enumerator);
+				task->destroy(task);
+				continue;
+			case NEED_MORE:
+				/* processed, but task needs another exchange */
+				continue;
+			case ALREADY_DONE:
+				break;
+			case FAILED:
+			default:
+				charon->bus->ike_updown(charon->bus, this->ike_sa, FALSE);
+				/* FALL */
+			case DESTROY_ME:
+				/* critical failure, destroy IKE_SA */
+				this->active_tasks->remove_at(this->active_tasks, enumerator);
+				enumerator->destroy(enumerator);
+				task->destroy(task);
+				return DESTROY_ME;
+		}
+		break;
+	}
+	enumerator->destroy(enumerator);
+
+	this->initiating.type = EXCHANGE_TYPE_UNDEFINED;
+	DESTROY_IF(this->initiating.packet);
+	this->initiating.packet = NULL;
+
+	if (this->queued && this->active_tasks->get_count(this->active_tasks) == 0)
+	{
+		queued = this->queued;
+		this->queued = NULL;
+		status = this->public.task_manager.process_message(
+											&this->public.task_manager, queued);
+		queued->destroy(queued);
+		if (status == DESTROY_ME)
+		{
+			return status;
+		}
+	}
+
+	return initiate(this);
+}
+
+/**
+ * Parse the given message and verify that it is valid.
+ */
+static status_t parse_message(private_task_manager_t *this, message_t *msg)
+{
+	status_t status;
+
+	status = msg->parse_body(msg, this->ike_sa->get_keymat(this->ike_sa));
+
+	if (status != SUCCESS)
+	{
+		switch (status)
+		{
+			case NOT_SUPPORTED:
+				DBG1(DBG_IKE, "unsupported exchange type");
+				send_notify(this, msg, INVALID_EXCHANGE_TYPE);
+				break;
+			case PARSE_ERROR:
+				DBG1(DBG_IKE, "message parsing failed");
+				send_notify(this, msg, PAYLOAD_MALFORMED);
+				break;
+			case VERIFY_ERROR:
+				DBG1(DBG_IKE, "message verification failed");
+				send_notify(this, msg, PAYLOAD_MALFORMED);
+				break;
+			case FAILED:
+				DBG1(DBG_IKE, "integrity check failed");
+				send_notify(this, msg, INVALID_HASH_INFORMATION);
+				break;
+			case INVALID_STATE:
+				DBG1(DBG_IKE, "found encrypted message, but no keys available");
+				send_notify(this, msg, PAYLOAD_MALFORMED);
+			default:
+				break;
+		}
+		DBG1(DBG_IKE, "%N %s with message ID %u processing failed",
+			 exchange_type_names, msg->get_exchange_type(msg),
+			 msg->get_request(msg) ? "request" : "response",
+			 msg->get_message_id(msg));
+
+		if (this->ike_sa->get_state(this->ike_sa) == IKE_CREATED)
+		{	/* invalid initiation attempt, close SA */
+			return DESTROY_ME;
+		}
+	}
+	return status;
+}
+
+METHOD(task_manager_t, process_message, status_t,
+	private_task_manager_t *this, message_t *msg)
+{
+	u_int32_t hash, mid, i;
+	host_t *me, *other;
+	status_t status;
+
+	/* TODO-IKEv1: update hosts more selectively */
+	me = msg->get_destination(msg);
+	other = msg->get_source(msg);
+	mid = msg->get_message_id(msg);
+	hash = chunk_hash(msg->get_packet_data(msg));
+	for (i = 0; i < MAX_OLD_HASHES; i++)
+	{
+		if (this->initiating.old_hashes[i] == hash)
+		{
+			if (this->initiating.packet &&
+				i == (this->initiating.old_hash_pos % MAX_OLD_HASHES) &&
+				(msg->get_exchange_type(msg) == QUICK_MODE ||
+				 msg->get_exchange_type(msg) == AGGRESSIVE))
+			{
+				DBG1(DBG_IKE, "received retransmit of response with ID %u, "
+					 "resending last request", mid);
+				charon->sender->send(charon->sender,
+						this->initiating.packet->clone(this->initiating.packet));
+				return SUCCESS;
+			}
+			DBG1(DBG_IKE, "received retransmit of response with ID %u, "
+				 "but next request already sent", mid);
+			return SUCCESS;
+		}
+	}
+
+	if ((mid && mid == this->initiating.mid) ||
+		(this->initiating.mid == 0 &&
+		 msg->get_exchange_type(msg) == this->initiating.type &&
+		 this->active_tasks->get_count(this->active_tasks)))
+	{
+		msg->set_request(msg, FALSE);
+		charon->bus->message(charon->bus, msg, TRUE, FALSE);
+		status = parse_message(this, msg);
+		if (status != SUCCESS)
+		{
+			return status;
+		}
+		this->ike_sa->set_statistic(this->ike_sa, STAT_INBOUND,
+									time_monotonic(NULL));
+		this->ike_sa->update_hosts(this->ike_sa, me, other, TRUE);
+		charon->bus->message(charon->bus, msg, TRUE, TRUE);
+		if (process_response(this, msg) != SUCCESS)
+		{
+			flush(this);
+			return DESTROY_ME;
+		}
+		this->initiating.old_hashes[(++this->initiating.old_hash_pos) %
+									MAX_OLD_HASHES] = hash;
+	}
+	else
+	{
+		if (hash == this->responding.hash)
+		{
+			if (this->responding.packet)
+			{
+				DBG1(DBG_IKE, "received retransmit of request with ID %u, "
+					 "retransmitting response", mid);
+				charon->sender->send(charon->sender,
+						this->responding.packet->clone(this->responding.packet));
+			}
+			else if (this->initiating.packet &&
+					 this->initiating.type == INFORMATIONAL_V1)
+			{
+				DBG1(DBG_IKE, "received retransmit of DPD request, "
+					 "retransmitting response");
+				charon->sender->send(charon->sender,
+						this->initiating.packet->clone(this->initiating.packet));
+			}
+			else
+			{
+				DBG1(DBG_IKE, "received retransmit of request with ID %u, "
+					 "but no response to retransmit", mid);
+			}
+			return SUCCESS;
+		}
+		if (msg->get_exchange_type(msg) == TRANSACTION &&
+			this->active_tasks->get_count(this->active_tasks))
+		{	/* main mode not yet complete, queue XAuth/Mode config tasks */
+			if (this->queued)
+			{
+				DBG1(DBG_IKE, "ignoring additional %N request, queue full",
+					 exchange_type_names, TRANSACTION);
+				return SUCCESS;
+			}
+			this->queued = message_create_from_packet(msg->get_packet(msg));
+			if (this->queued->parse_header(this->queued) != SUCCESS)
+			{
+				this->queued->destroy(this->queued);
+				this->queued = NULL;
+				return FAILED;
+			}
+			DBG1(DBG_IKE, "queueing %N request as tasks still active",
+				 exchange_type_names, TRANSACTION);
+			return SUCCESS;
+		}
+
+		msg->set_request(msg, TRUE);
+		charon->bus->message(charon->bus, msg, TRUE, FALSE);
+		status = parse_message(this, msg);
+		if (status != SUCCESS)
+		{
+			return status;
+		}
+		/* if this IKE_SA is virgin, we check for a config */
+		if (this->ike_sa->get_ike_cfg(this->ike_sa) == NULL)
+		{
+			ike_sa_id_t *ike_sa_id;
+			ike_cfg_t *ike_cfg;
+			job_t *job;
+
+			ike_cfg = charon->backends->get_ike_cfg(charon->backends, me, other);
+			if (ike_cfg == NULL)
+			{
+				/* no config found for these hosts, destroy */
+				DBG1(DBG_IKE, "no IKE config found for %H...%H, sending %N",
+					 me, other, notify_type_names, NO_PROPOSAL_CHOSEN);
+				send_notify(this, msg, NO_PROPOSAL_CHOSEN);
+				return DESTROY_ME;
+			}
+			this->ike_sa->set_ike_cfg(this->ike_sa, ike_cfg);
+			ike_cfg->destroy(ike_cfg);
+			/* add a timeout if peer does not establish it completely */
+			ike_sa_id = this->ike_sa->get_id(this->ike_sa);
+			job = (job_t*)delete_ike_sa_job_create(ike_sa_id, FALSE);
+			lib->scheduler->schedule_job(lib->scheduler, job,
+					lib->settings->get_int(lib->settings,
+							"%s.half_open_timeout", HALF_OPEN_IKE_SA_TIMEOUT,
+							charon->name));
+		}
+		this->ike_sa->update_hosts(this->ike_sa, me, other, TRUE);
+		charon->bus->message(charon->bus, msg, TRUE, TRUE);
+		if (process_request(this, msg) != SUCCESS)
+		{
+			flush(this);
+			return DESTROY_ME;
+		}
+		this->responding.hash = hash;
+	}
+	return SUCCESS;
+}
+
+METHOD(task_manager_t, queue_task, void,
+	private_task_manager_t *this, task_t *task)
+{
+	DBG2(DBG_IKE, "queueing %N task", task_type_names, task->get_type(task));
+	this->queued_tasks->insert_last(this->queued_tasks, task);
+}
+
+/**
+ * Check if a given task has been queued already
+ */
+static bool has_queued(private_task_manager_t *this, task_type_t type)
+{
+	enumerator_t *enumerator;
+	bool found = FALSE;
+	task_t *task;
+
+	enumerator = this->queued_tasks->create_enumerator(this->queued_tasks);
+	while (enumerator->enumerate(enumerator, &task))
+	{
+		if (task->get_type(task) == type)
+		{
+			found = TRUE;
+			break;
+		}
+	}
+	enumerator->destroy(enumerator);
+	return found;
+}
+
+METHOD(task_manager_t, queue_ike, void,
+	private_task_manager_t *this)
+{
+	peer_cfg_t *peer_cfg;
+
+	if (!has_queued(this, TASK_ISAKMP_VENDOR))
+	{
+		queue_task(this, (task_t*)isakmp_vendor_create(this->ike_sa, TRUE));
+	}
+	if (!has_queued(this, TASK_ISAKMP_CERT_PRE))
+	{
+		queue_task(this, (task_t*)isakmp_cert_pre_create(this->ike_sa, TRUE));
+	}
+	peer_cfg = this->ike_sa->get_peer_cfg(this->ike_sa);
+	if (peer_cfg->use_aggressive(peer_cfg))
+	{
+		if (!has_queued(this, TASK_AGGRESSIVE_MODE))
+		{
+			queue_task(this, (task_t*)aggressive_mode_create(this->ike_sa, TRUE));
+		}
+	}
+	else
+	{
+		if (!has_queued(this, TASK_MAIN_MODE))
+		{
+			queue_task(this, (task_t*)main_mode_create(this->ike_sa, TRUE));
+		}
+	}
+	if (!has_queued(this, TASK_ISAKMP_CERT_POST))
+	{
+		queue_task(this, (task_t*)isakmp_cert_post_create(this->ike_sa, TRUE));
+	}
+	if (!has_queued(this, TASK_ISAKMP_NATD))
+	{
+		queue_task(this, (task_t*)isakmp_natd_create(this->ike_sa, TRUE));
+	}
+}
+
+METHOD(task_manager_t, queue_ike_reauth, void,
+	private_task_manager_t *this)
+{
+	enumerator_t *enumerator;
+	child_sa_t *child_sa;
+	ike_sa_t *new;
+	host_t *host;
+
+	new = charon->ike_sa_manager->checkout_new(charon->ike_sa_manager,
+								this->ike_sa->get_version(this->ike_sa), TRUE);
+	if (!new)
+	{	/* shouldn't happen */
+		return;
+	}
+
+	new->set_peer_cfg(new, this->ike_sa->get_peer_cfg(this->ike_sa));
+	host = this->ike_sa->get_other_host(this->ike_sa);
+	new->set_other_host(new, host->clone(host));
+	host = this->ike_sa->get_my_host(this->ike_sa);
+	new->set_my_host(new, host->clone(host));
+	enumerator = this->ike_sa->create_virtual_ip_enumerator(this->ike_sa, TRUE);
+	while (enumerator->enumerate(enumerator, &host))
+	{
+		new->add_virtual_ip(new, TRUE, host);
+	}
+	enumerator->destroy(enumerator);
+
+	enumerator = this->ike_sa->create_child_sa_enumerator(this->ike_sa);
+	while (enumerator->enumerate(enumerator, &child_sa))
+	{
+		this->ike_sa->remove_child_sa(this->ike_sa, enumerator);
+		new->add_child_sa(new, child_sa);
+	}
+	enumerator->destroy(enumerator);
+
+	if (!new->get_child_count(new))
+	{	/* check if a Quick Mode task is queued (UNITY_LOAD_BALANCE case) */
+		task_t *task;
+
+		enumerator = this->queued_tasks->create_enumerator(this->queued_tasks);
+		while (enumerator->enumerate(enumerator, &task))
+		{
+			if (task->get_type(task) == TASK_QUICK_MODE)
+			{
+				this->queued_tasks->remove_at(this->queued_tasks, enumerator);
+				task->migrate(task, new);
+				new->queue_task(new, task);
+			}
+		}
+		enumerator->destroy(enumerator);
+	}
+
+	if (new->initiate(new, NULL, 0, NULL, NULL) != DESTROY_ME)
+	{
+		charon->ike_sa_manager->checkin(charon->ike_sa_manager, new);
+		this->ike_sa->set_state(this->ike_sa, IKE_REKEYING);
+	}
+	else
+	{
+		charon->ike_sa_manager->checkin_and_destroy(charon->ike_sa_manager, new);
+		DBG1(DBG_IKE, "reauthenticating IKE_SA failed");
+	}
+	charon->bus->set_sa(charon->bus, this->ike_sa);
+}
+
+METHOD(task_manager_t, queue_ike_rekey, void,
+	private_task_manager_t *this)
+{
+	queue_ike_reauth(this);
+}
+
+METHOD(task_manager_t, queue_ike_delete, void,
+	private_task_manager_t *this)
+{
+	enumerator_t *enumerator;
+	child_sa_t *child_sa;
+
+	enumerator = this->ike_sa->create_child_sa_enumerator(this->ike_sa);
+	while (enumerator->enumerate(enumerator, &child_sa))
+	{
+		queue_task(this, (task_t*)
+			quick_delete_create(this->ike_sa, child_sa->get_protocol(child_sa),
+								child_sa->get_spi(child_sa, TRUE), FALSE, FALSE));
+	}
+	enumerator->destroy(enumerator);
+
+	queue_task(this, (task_t*)isakmp_delete_create(this->ike_sa, TRUE));
+}
+
+METHOD(task_manager_t, queue_mobike, void,
+	private_task_manager_t *this, bool roam, bool address)
+{
+	/* Not supported in IKEv1 */
+}
+
+METHOD(task_manager_t, queue_child, void,
+	private_task_manager_t *this, child_cfg_t *cfg, u_int32_t reqid,
+	traffic_selector_t *tsi, traffic_selector_t *tsr)
+{
+	quick_mode_t *task;
+
+	task = quick_mode_create(this->ike_sa, cfg, tsi, tsr);
+	task->use_reqid(task, reqid);
+
+	queue_task(this, &task->task);
+}
+
+/**
+ * Check if two CHILD_SAs have the same traffic selector
+ */
+static bool have_equal_ts(child_sa_t *a, child_sa_t *b, bool local)
+{
+	linked_list_t *list;
+	traffic_selector_t *ts_a, *ts_b;
+
+	list = a->get_traffic_selectors(a, local);
+	if (list->get_first(list, (void**)&ts_a) == SUCCESS)
+	{
+		list = b->get_traffic_selectors(b, local);
+		if (list->get_first(list, (void**)&ts_b) == SUCCESS)
+		{
+			return ts_a->equals(ts_a, ts_b);
+		}
+	}
+	return FALSE;
+}
+
+/**
+ * Check if a CHILD_SA is redundant and we should delete instead of rekey
+ */
+static bool is_redundant(private_task_manager_t *this, child_sa_t *child_sa)
+{
+	enumerator_t *enumerator;
+	child_sa_t *current;
+	bool redundant = FALSE;
+
+	enumerator = this->ike_sa->create_child_sa_enumerator(this->ike_sa);
+	while (enumerator->enumerate(enumerator, &current))
+	{
+		if (current->get_state(current) == CHILD_INSTALLED &&
+			streq(current->get_name(current), child_sa->get_name(child_sa)) &&
+			have_equal_ts(current, child_sa, TRUE) &&
+			have_equal_ts(current, child_sa, FALSE) &&
+			current->get_lifetime(current, FALSE) >
+				child_sa->get_lifetime(child_sa, FALSE))
+		{
+			DBG1(DBG_IKE, "deleting redundant CHILD_SA %s{%d}",
+				 child_sa->get_name(child_sa), child_sa->get_reqid(child_sa));
+			redundant = TRUE;
+			break;
+		}
+	}
+	enumerator->destroy(enumerator);
+
+	return redundant;
+}
+
+/**
+ * Get the first traffic selector of a CHILD_SA, local or remote
+ */
+static traffic_selector_t* get_first_ts(child_sa_t *child_sa, bool local)
+{
+	traffic_selector_t *ts = NULL;
+	linked_list_t *list;
+
+	list = child_sa->get_traffic_selectors(child_sa, local);
+	if (list->get_first(list, (void**)&ts) == SUCCESS)
+	{
+		return ts;
+	}
+	return NULL;
+}
+
+METHOD(task_manager_t, queue_child_rekey, void,
+	private_task_manager_t *this, protocol_id_t protocol, u_int32_t spi)
+{
+	child_sa_t *child_sa;
+	child_cfg_t *cfg;
+	quick_mode_t *task;
+
+	child_sa = this->ike_sa->get_child_sa(this->ike_sa, protocol, spi, TRUE);
+	if (!child_sa)
+	{
+		child_sa = this->ike_sa->get_child_sa(this->ike_sa, protocol, spi, FALSE);
+	}
+	if (child_sa && child_sa->get_state(child_sa) == CHILD_INSTALLED)
+	{
+		if (is_redundant(this, child_sa))
+		{
+			queue_task(this, (task_t*)quick_delete_create(this->ike_sa,
+												protocol, spi, FALSE, FALSE));
+		}
+		else
+		{
+			child_sa->set_state(child_sa, CHILD_REKEYING);
+			cfg = child_sa->get_config(child_sa);
+			task = quick_mode_create(this->ike_sa, cfg->get_ref(cfg),
+				get_first_ts(child_sa, TRUE), get_first_ts(child_sa, FALSE));
+			task->use_reqid(task, child_sa->get_reqid(child_sa));
+			task->rekey(task, child_sa->get_spi(child_sa, TRUE));
+
+			queue_task(this, &task->task);
+		}
+	}
+}
+
+METHOD(task_manager_t, queue_child_delete, void,
+	private_task_manager_t *this, protocol_id_t protocol, u_int32_t spi,
+	bool expired)
+{
+	queue_task(this, (task_t*)quick_delete_create(this->ike_sa, protocol,
+												  spi, FALSE, expired));
+}
+
+METHOD(task_manager_t, queue_dpd, void,
+	private_task_manager_t *this)
+{
+	peer_cfg_t *peer_cfg;
+	u_int32_t t, retransmit;
+
+	queue_task(this, (task_t*)isakmp_dpd_create(this->ike_sa, DPD_R_U_THERE,
+												this->dpd_send++));
+	peer_cfg = this->ike_sa->get_peer_cfg(this->ike_sa);
+
+	/* compute timeout in milliseconds */
+	t = 1000 * peer_cfg->get_dpd_timeout(peer_cfg);
+	if (t == 0)
+	{
+		/* use the same timeout as a retransmitting IKE message would have */
+		for (retransmit = 0; retransmit <= this->retransmit_tries; retransmit++)
+		{
+			t += (u_int32_t)(this->retransmit_timeout * 1000.0 *
+							pow(this->retransmit_base, retransmit));
+		}
+	}
+
+	/* schedule DPD timeout job */
+	lib->scheduler->schedule_job_ms(lib->scheduler,
+		(job_t*)dpd_timeout_job_create(this->ike_sa->get_id(this->ike_sa)), t);
+}
+
+METHOD(task_manager_t, adopt_tasks, void,
+	private_task_manager_t *this, task_manager_t *other_public)
+{
+	private_task_manager_t *other = (private_task_manager_t*)other_public;
+	task_t *task;
+
+	/* move queued tasks from other to this */
+	while (other->queued_tasks->remove_last(other->queued_tasks,
+												(void**)&task) == SUCCESS)
+	{
+		DBG2(DBG_IKE, "migrating %N task", task_type_names, task->get_type(task));
+		task->migrate(task, this->ike_sa);
+		this->queued_tasks->insert_first(this->queued_tasks, task);
+	}
+}
+
+METHOD(task_manager_t, busy, bool,
+	private_task_manager_t *this)
+{
+	return (this->active_tasks->get_count(this->active_tasks) > 0);
+}
+
+METHOD(task_manager_t, incr_mid, void,
+	private_task_manager_t *this, bool initiate)
+{
+}
+
+METHOD(task_manager_t, reset, void,
+	private_task_manager_t *this, u_int32_t initiate, u_int32_t respond)
+{
+	enumerator_t *enumerator;
+	task_t *task;
+
+	/* reset message counters and retransmit packets */
+	DESTROY_IF(this->responding.packet);
+	DESTROY_IF(this->initiating.packet);
+	this->responding.packet = NULL;
+	this->responding.seqnr = RESPONDING_SEQ;
+	this->responding.retransmitted = 0;
+	this->initiating.packet = NULL;
+	this->initiating.mid = 0;
+	this->initiating.seqnr = 0;
+	this->initiating.retransmitted = 0;
+	this->initiating.type = EXCHANGE_TYPE_UNDEFINED;
+	if (initiate != UINT_MAX)
+	{
+		this->dpd_send = initiate;
+	}
+	if (respond != UINT_MAX)
+	{
+		this->dpd_recv = respond;
+	}
+
+	/* reset queued tasks */
+	enumerator = this->queued_tasks->create_enumerator(this->queued_tasks);
+	while (enumerator->enumerate(enumerator, &task))
+	{
+		task->migrate(task, this->ike_sa);
+	}
+	enumerator->destroy(enumerator);
+
+	/* reset active tasks */
+	while (this->active_tasks->remove_last(this->active_tasks,
+										   (void**)&task) == SUCCESS)
+	{
+		task->migrate(task, this->ike_sa);
+		this->queued_tasks->insert_first(this->queued_tasks, task);
+	}
+}
+
+METHOD(task_manager_t, create_task_enumerator, enumerator_t*,
+	private_task_manager_t *this, task_queue_t queue)
+{
+	switch (queue)
+	{
+		case TASK_QUEUE_ACTIVE:
+			return this->active_tasks->create_enumerator(this->active_tasks);
+		case TASK_QUEUE_PASSIVE:
+			return this->passive_tasks->create_enumerator(this->passive_tasks);
+		case TASK_QUEUE_QUEUED:
+			return this->queued_tasks->create_enumerator(this->queued_tasks);
+		default:
+			return enumerator_create_empty();
+	}
+}
+
+METHOD(task_manager_t, destroy, void,
+	private_task_manager_t *this)
+{
+	flush(this);
+
+	this->active_tasks->destroy(this->active_tasks);
+	this->queued_tasks->destroy(this->queued_tasks);
+	this->passive_tasks->destroy(this->passive_tasks);
+
+	DESTROY_IF(this->queued);
+	DESTROY_IF(this->responding.packet);
+	DESTROY_IF(this->initiating.packet);
+	DESTROY_IF(this->rng);
+	free(this);
+}
+
+/*
+ * see header file
+ */
+task_manager_v1_t *task_manager_v1_create(ike_sa_t *ike_sa)
+{
+	private_task_manager_t *this;
+
+	INIT(this,
+		.public = {
+			.task_manager = {
+				.process_message = _process_message,
+				.queue_task = _queue_task,
+				.queue_ike = _queue_ike,
+				.queue_ike_rekey = _queue_ike_rekey,
+				.queue_ike_reauth = _queue_ike_reauth,
+				.queue_ike_delete = _queue_ike_delete,
+				.queue_mobike = _queue_mobike,
+				.queue_child = _queue_child,
+				.queue_child_rekey = _queue_child_rekey,
+				.queue_child_delete = _queue_child_delete,
+				.queue_dpd = _queue_dpd,
+				.initiate = _initiate,
+				.retransmit = _retransmit,
+				.incr_mid = _incr_mid,
+				.reset = _reset,
+				.adopt_tasks = _adopt_tasks,
+				.busy = _busy,
+				.create_task_enumerator = _create_task_enumerator,
+				.flush_queue = _flush_queue,
+				.destroy = _destroy,
+			},
+		},
+		.initiating = {
+			.type = EXCHANGE_TYPE_UNDEFINED,
+		},
+		.responding = {
+			.seqnr = RESPONDING_SEQ,
+		},
+		.ike_sa = ike_sa,
+		.rng = lib->crypto->create_rng(lib->crypto, RNG_WEAK),
+		.queued_tasks = linked_list_create(),
+		.active_tasks = linked_list_create(),
+		.passive_tasks = linked_list_create(),
+		.retransmit_tries = lib->settings->get_int(lib->settings,
+					"%s.retransmit_tries", RETRANSMIT_TRIES, charon->name),
+		.retransmit_timeout = lib->settings->get_double(lib->settings,
+					"%s.retransmit_timeout", RETRANSMIT_TIMEOUT, charon->name),
+		.retransmit_base = lib->settings->get_double(lib->settings,
+					"%s.retransmit_base", RETRANSMIT_BASE, charon->name),
+	);
+
+	if (!this->rng)
+	{
+		DBG1(DBG_IKE, "no RNG found, unable to create IKE_SA");
+		destroy(this);
+		return NULL;
+	}
+	if (!this->rng->get_bytes(this->rng, sizeof(this->dpd_send),
+							  (void*)&this->dpd_send))
+	{
+		DBG1(DBG_IKE, "failed to allocate message ID, unable to create IKE_SA");
+		destroy(this);
+		return NULL;
+	}
+	this->dpd_send &= 0x7FFFFFFF;
+
+	return &this->public;
+}
+