/*
 * Copyright (C) 2006-2008 Tobias Brunner
 * Copyright (C) 2006 Daniel Roethlisberger
 * Copyright (C) 2005-2009 Martin Willi
 * Copyright (C) 2005 Jan Hutter
 * 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 <string.h>
#include <sys/stat.h>
#include <errno.h>
#include <time.h>

#include "ike_sa.h"

#include <library.h>
#include <hydra.h>
#include <daemon.h>
#include <utils/linked_list.h>
#include <utils/lexparser.h>
#include <sa/task_manager.h>
#include <sa/tasks/ike_init.h>
#include <sa/tasks/ike_natd.h>
#include <sa/tasks/ike_mobike.h>
#include <sa/tasks/ike_auth.h>
#include <sa/tasks/ike_auth_lifetime.h>
#include <sa/tasks/ike_config.h>
#include <sa/tasks/ike_cert_pre.h>
#include <sa/tasks/ike_cert_post.h>
#include <sa/tasks/ike_rekey.h>
#include <sa/tasks/ike_reauth.h>
#include <sa/tasks/ike_delete.h>
#include <sa/tasks/ike_dpd.h>
#include <sa/tasks/ike_vendor.h>
#include <sa/tasks/child_create.h>
#include <sa/tasks/child_delete.h>
#include <sa/tasks/child_rekey.h>
#include <processing/jobs/retransmit_job.h>
#include <processing/jobs/delete_ike_sa_job.h>
#include <processing/jobs/send_dpd_job.h>
#include <processing/jobs/send_keepalive_job.h>
#include <processing/jobs/rekey_ike_sa_job.h>
#include <encoding/payloads/unknown_payload.h>

#ifdef ME
#include <sa/tasks/ike_me.h>
#include <processing/jobs/initiate_mediation_job.h>
#endif

ENUM(ike_sa_state_names, IKE_CREATED, IKE_DESTROYING,
	"CREATED",
	"CONNECTING",
	"ESTABLISHED",
	"PASSIVE",
	"REKEYING",
	"DELETING",
	"DESTROYING",
);

typedef struct private_ike_sa_t private_ike_sa_t;
typedef struct attribute_entry_t attribute_entry_t;

/**
 * Private data of an ike_sa_t object.
 */
struct private_ike_sa_t {

	/**
	 * Public members
	 */
	ike_sa_t public;

	/**
	 * Identifier for the current IKE_SA.
	 */
	ike_sa_id_t *ike_sa_id;

	/**
	 * unique numerical ID for this IKE_SA.
	 */
	u_int32_t unique_id;

	/**
	 * Current state of the IKE_SA
	 */
	ike_sa_state_t state;

	/**
	 * IKE configuration used to set up this IKE_SA
	 */
	ike_cfg_t *ike_cfg;

	/**
	 * Peer and authentication information to establish IKE_SA.
	 */
	peer_cfg_t *peer_cfg;

	/**
	 * currently used authentication ruleset, local (as auth_cfg_t)
	 */
	auth_cfg_t *my_auth;

	/**
	 * list of completed local authentication rounds
	 */
	linked_list_t *my_auths;

	/**
	 * list of completed remote authentication rounds
	 */
	linked_list_t *other_auths;

	/**
	 * currently used authentication constraints, remote (as auth_cfg_t)
	 */
	auth_cfg_t *other_auth;

	/**
	 * Selected IKE proposal
	 */
	proposal_t *proposal;

	/**
	 * Juggles tasks to process messages
	 */
	task_manager_t *task_manager;

	/**
	 * Address of local host
	 */
	host_t *my_host;

	/**
	 * Address of remote host
	 */
	host_t *other_host;

#ifdef ME
	/**
	 * Are we mediation server
	 */
	bool is_mediation_server;

	/**
	 * Server reflexive host
	 */
	host_t *server_reflexive_host;

	/**
	 * Connect ID
	 */
	chunk_t connect_id;
#endif /* ME */

	/**
	 * Identification used for us
	 */
	identification_t *my_id;

	/**
	 * Identification used for other
	 */
	identification_t *other_id;

	/**
	 * set of extensions the peer supports
	 */
	ike_extension_t extensions;

	/**
	 * set of condition flags currently enabled for this IKE_SA
	 */
	ike_condition_t conditions;

	/**
	 * Linked List containing the child sa's of the current IKE_SA.
	 */
	linked_list_t *child_sas;

	/**
	 * keymat of this IKE_SA
	 */
	keymat_t *keymat;

	/**
	 * Virtual IP on local host, if any
	 */
	host_t *my_virtual_ip;

	/**
	 * Virtual IP on remote host, if any
	 */
	host_t *other_virtual_ip;

	/**
	 * List of configuration attributes (attribute_entry_t)
	 */
	linked_list_t *attributes;

	/**
	 * list of peers additional addresses, transmitted via MOBIKE
	 */
	linked_list_t *additional_addresses;

	/**
	 * previously value of received DESTINATION_IP hash
	 */
	chunk_t nat_detection_dest;

	/**
	 * number pending UPDATE_SA_ADDRESS (MOBIKE)
	 */
	u_int32_t pending_updates;

	/**
	 * NAT keep alive interval
	 */
	u_int32_t keepalive_interval;

	/**
	 * Timestamps for this IKE_SA
	 */
	u_int32_t stats[STAT_MAX];

	/**
	 * how many times we have retried so far (keyingtries)
	 */
	u_int32_t keyingtry;

	/**
	 * local host address to be used for IKE, set via MIGRATE kernel message
	 */
	host_t *local_host;

	/**
	 * remote host address to be used for IKE, set via MIGRATE kernel message
	 */
	host_t *remote_host;
};

/**
 * Entry to maintain install configuration attributes during IKE_SA lifetime
 */
struct attribute_entry_t {
	/** handler used to install this attribute */
	attribute_handler_t *handler;
	/** attribute type */
	configuration_attribute_type_t type;
	/** attribute data */
	chunk_t data;
};

/**
 * get the time of the latest traffic processed by the kernel
 */
static time_t get_use_time(private_ike_sa_t* this, bool inbound)
{
	enumerator_t *enumerator;
	child_sa_t *child_sa;
	time_t use_time, current;

	if (inbound)
	{
		use_time = this->stats[STAT_INBOUND];
	}
	else
	{
		use_time = this->stats[STAT_OUTBOUND];
	}
	enumerator = this->child_sas->create_enumerator(this->child_sas);
	while (enumerator->enumerate(enumerator, &child_sa))
	{
		child_sa->get_usestats(child_sa, inbound, &current, NULL);
		use_time = max(use_time, current);
	}
	enumerator->destroy(enumerator);

	return use_time;
}

METHOD(ike_sa_t, get_unique_id, u_int32_t,
	private_ike_sa_t *this)
{
	return this->unique_id;
}

METHOD(ike_sa_t, get_name, char*,
	private_ike_sa_t *this)
{
	if (this->peer_cfg)
	{
		return this->peer_cfg->get_name(this->peer_cfg);
	}
	return "(unnamed)";
}

METHOD(ike_sa_t, get_statistic, u_int32_t,
	private_ike_sa_t *this, statistic_t kind)
{
	if (kind < STAT_MAX)
	{
		return this->stats[kind];
	}
	return 0;
}

METHOD(ike_sa_t, get_my_host, host_t*,
	private_ike_sa_t *this)
{
	return this->my_host;
}

METHOD(ike_sa_t, set_my_host, void,
	private_ike_sa_t *this, host_t *me)
{
	DESTROY_IF(this->my_host);
	this->my_host = me;
}

METHOD(ike_sa_t, get_other_host, host_t*,
	private_ike_sa_t *this)
{
	return this->other_host;
}

METHOD(ike_sa_t, set_other_host, void,
	private_ike_sa_t *this, host_t *other)
{
	DESTROY_IF(this->other_host);
	this->other_host = other;
}

METHOD(ike_sa_t, get_peer_cfg, peer_cfg_t*,
	private_ike_sa_t *this)
{
	return this->peer_cfg;
}

METHOD(ike_sa_t, set_peer_cfg, void,
	private_ike_sa_t *this, peer_cfg_t *peer_cfg)
{
	DESTROY_IF(this->peer_cfg);
	peer_cfg->get_ref(peer_cfg);
	this->peer_cfg = peer_cfg;

	if (this->ike_cfg == NULL)
	{
		this->ike_cfg = peer_cfg->get_ike_cfg(peer_cfg);
		this->ike_cfg->get_ref(this->ike_cfg);
	}
}

METHOD(ike_sa_t, get_auth_cfg, auth_cfg_t*,
	private_ike_sa_t *this, bool local)
{
	if (local)
	{
		return this->my_auth;
	}
	return this->other_auth;
}

METHOD(ike_sa_t, add_auth_cfg, void,
	private_ike_sa_t *this, bool local, auth_cfg_t *cfg)
{
	if (local)
	{
		this->my_auths->insert_last(this->my_auths, cfg);
	}
	else
	{
		this->other_auths->insert_last(this->other_auths, cfg);
	}
}

METHOD(ike_sa_t, create_auth_cfg_enumerator, enumerator_t*,
	private_ike_sa_t *this, bool local)
{
	if (local)
	{
		return this->my_auths->create_enumerator(this->my_auths);
	}
	return this->other_auths->create_enumerator(this->other_auths);
}

/**
 * Flush the stored authentication round information
 */
static void flush_auth_cfgs(private_ike_sa_t *this)
{
	auth_cfg_t *cfg;

	while (this->my_auths->remove_last(this->my_auths,
									   (void**)&cfg) == SUCCESS)
	{
		cfg->destroy(cfg);
	}
	while (this->other_auths->remove_last(this->other_auths,
										  (void**)&cfg) == SUCCESS)
	{
		cfg->destroy(cfg);
	}
}

METHOD(ike_sa_t, get_proposal, proposal_t*,
	private_ike_sa_t *this)
{
	return this->proposal;
}

METHOD(ike_sa_t, set_proposal, void,
	private_ike_sa_t *this, proposal_t *proposal)
{
	DESTROY_IF(this->proposal);
	this->proposal = proposal->clone(proposal);
}

METHOD(ike_sa_t, set_message_id, void,
	private_ike_sa_t *this, bool initiate, u_int32_t mid)
{
	if (initiate)
	{
		this->task_manager->reset(this->task_manager, mid, UINT_MAX);
	}
	else
	{
		this->task_manager->reset(this->task_manager, UINT_MAX, mid);
	}
}

METHOD(ike_sa_t, send_keepalive, void,
	private_ike_sa_t *this)
{
	send_keepalive_job_t *job;
	time_t last_out, now, diff;

	if (!(this->conditions & COND_NAT_HERE) || this->keepalive_interval == 0)
	{	/* disable keep alives if we are not NATed anymore */
		return;
	}

	last_out = get_use_time(this, FALSE);
	now = time_monotonic(NULL);

	diff = now - last_out;

	if (diff >= this->keepalive_interval)
	{
		packet_t *packet;
		chunk_t data;

		packet = packet_create();
		packet->set_source(packet, this->my_host->clone(this->my_host));
		packet->set_destination(packet, this->other_host->clone(this->other_host));
		data.ptr = malloc(1);
		data.ptr[0] = 0xFF;
		data.len = 1;
		packet->set_data(packet, data);
		DBG1(DBG_IKE, "sending keep alive");
		charon->sender->send(charon->sender, packet);
		diff = 0;
	}
	job = send_keepalive_job_create(this->ike_sa_id);
	lib->scheduler->schedule_job(lib->scheduler, (job_t*)job,
								 this->keepalive_interval - diff);
}

METHOD(ike_sa_t, get_ike_cfg, ike_cfg_t*,
	private_ike_sa_t *this)
{
	return this->ike_cfg;
}

METHOD(ike_sa_t, set_ike_cfg, void,
	private_ike_sa_t *this, ike_cfg_t *ike_cfg)
{
	ike_cfg->get_ref(ike_cfg);
	this->ike_cfg = ike_cfg;
}

METHOD(ike_sa_t, enable_extension, void,
	private_ike_sa_t *this, ike_extension_t extension)
{
	this->extensions |= extension;
}

METHOD(ike_sa_t, supports_extension, bool,
	private_ike_sa_t *this, ike_extension_t extension)
{
	return (this->extensions & extension) != FALSE;
}

METHOD(ike_sa_t, has_condition, bool,
	private_ike_sa_t *this, ike_condition_t condition)
{
	return (this->conditions & condition) != FALSE;
}

METHOD(ike_sa_t, set_condition, void,
	private_ike_sa_t *this, ike_condition_t condition, bool enable)
{
	if (has_condition(this, condition) != enable)
	{
		if (enable)
		{
			this->conditions |= condition;
			switch (condition)
			{
				case COND_NAT_HERE:
					DBG1(DBG_IKE, "local host is behind NAT, sending keep alives");
					this->conditions |= COND_NAT_ANY;
					send_keepalive(this);
					break;
				case COND_NAT_THERE:
					DBG1(DBG_IKE, "remote host is behind NAT");
					this->conditions |= COND_NAT_ANY;
					break;
				case COND_NAT_FAKE:
					DBG1(DBG_IKE, "faking NAT situation to enforce UDP encapsulation");
					this->conditions |= COND_NAT_ANY;
					break;
				default:
					break;
			}
		}
		else
		{
			this->conditions &= ~condition;
			switch (condition)
			{
				case COND_NAT_HERE:
				case COND_NAT_FAKE:
				case COND_NAT_THERE:
					set_condition(this, COND_NAT_ANY,
								  has_condition(this, COND_NAT_HERE) ||
								  has_condition(this, COND_NAT_THERE) ||
								  has_condition(this, COND_NAT_FAKE));
					break;
				default:
					break;
			}
		}
	}
}

METHOD(ike_sa_t, send_dpd, status_t,
	private_ike_sa_t *this)
{
	job_t *job;
	time_t diff, delay;

	delay = this->peer_cfg->get_dpd(this->peer_cfg);
	if (this->task_manager->busy(this->task_manager))
	{
		/* an exchange is in the air, no need to start a DPD check */
		diff = 0;
	}
	else
	{
		/* check if there was any inbound traffic */
		time_t last_in, now;
		last_in = get_use_time(this, TRUE);
		now = time_monotonic(NULL);
		diff = now - last_in;
		if (!delay || diff >= delay)
		{
			/* to long ago, initiate dead peer detection */
			task_t *task;
			ike_mobike_t *mobike;

			if (supports_extension(this, EXT_MOBIKE) &&
				has_condition(this, COND_NAT_HERE))
			{
				/* use mobike enabled DPD to detect NAT mapping changes */
				mobike = ike_mobike_create(&this->public, TRUE);
				mobike->dpd(mobike);
				task = &mobike->task;
			}
			else
			{
				task = (task_t*)ike_dpd_create(TRUE);
			}
			diff = 0;
			DBG1(DBG_IKE, "sending DPD request");

			this->task_manager->queue_task(this->task_manager, task);
			this->task_manager->initiate(this->task_manager);
		}
	}
	/* recheck in "interval" seconds */
	if (delay)
	{
		job = (job_t*)send_dpd_job_create(this->ike_sa_id);
		lib->scheduler->schedule_job(lib->scheduler, job, delay - diff);
	}
	return SUCCESS;
}

METHOD(ike_sa_t, get_state, ike_sa_state_t,
	private_ike_sa_t *this)
{
	return this->state;
}

METHOD(ike_sa_t, set_state, void,
	private_ike_sa_t *this, ike_sa_state_t state)
{
	DBG2(DBG_IKE, "IKE_SA %s[%d] state change: %N => %N",
		 get_name(this), this->unique_id,
		 ike_sa_state_names, this->state,
		 ike_sa_state_names, state);

	switch (state)
	{
		case IKE_ESTABLISHED:
		{
			if (this->state == IKE_CONNECTING ||
				this->state == IKE_PASSIVE)
			{
				job_t *job;
				u_int32_t t;

				/* calculate rekey, reauth and lifetime */
				this->stats[STAT_ESTABLISHED] = time_monotonic(NULL);

				/* schedule rekeying if we have a time which is smaller than
				 * an already scheduled rekeying */
				t = this->peer_cfg->get_rekey_time(this->peer_cfg);
				if (t && (this->stats[STAT_REKEY] == 0 ||
					(this->stats[STAT_REKEY] > t + this->stats[STAT_ESTABLISHED])))
				{
					this->stats[STAT_REKEY] = t + this->stats[STAT_ESTABLISHED];
					job = (job_t*)rekey_ike_sa_job_create(this->ike_sa_id, FALSE);
					lib->scheduler->schedule_job(lib->scheduler, job, t);
					DBG1(DBG_IKE, "scheduling rekeying in %ds", t);
				}
				t = this->peer_cfg->get_reauth_time(this->peer_cfg);
				if (t && (this->stats[STAT_REAUTH] == 0 ||
					(this->stats[STAT_REAUTH] > t + this->stats[STAT_ESTABLISHED])))
				{
					this->stats[STAT_REAUTH] = t + this->stats[STAT_ESTABLISHED];
					job = (job_t*)rekey_ike_sa_job_create(this->ike_sa_id, TRUE);
					lib->scheduler->schedule_job(lib->scheduler, job, t);
					DBG1(DBG_IKE, "scheduling reauthentication in %ds", t);
				}
				t = this->peer_cfg->get_over_time(this->peer_cfg);
				if (this->stats[STAT_REKEY] || this->stats[STAT_REAUTH])
				{
					if (this->stats[STAT_REAUTH] == 0)
					{
						this->stats[STAT_DELETE] = this->stats[STAT_REKEY];
					}
					else if (this->stats[STAT_REKEY] == 0)
					{
						this->stats[STAT_DELETE] = this->stats[STAT_REAUTH];
					}
					else
					{
						this->stats[STAT_DELETE] = min(this->stats[STAT_REKEY],
													   this->stats[STAT_REAUTH]);
					}
					this->stats[STAT_DELETE] += t;
					t = this->stats[STAT_DELETE] - this->stats[STAT_ESTABLISHED];
					job = (job_t*)delete_ike_sa_job_create(this->ike_sa_id, TRUE);
					lib->scheduler->schedule_job(lib->scheduler, job, t);
					DBG1(DBG_IKE, "maximum IKE_SA lifetime %ds", t);
				}

				/* start DPD checks */
				if (this->peer_cfg->get_dpd(this->peer_cfg))
				{
					send_dpd(this);
				}
			}
			break;
		}
		case IKE_DELETING:
		{
			/* delete may fail if a packet gets lost, so set a timeout */
			job_t *job = (job_t*)delete_ike_sa_job_create(this->ike_sa_id, TRUE);
			lib->scheduler->schedule_job(lib->scheduler, job,
										 HALF_OPEN_IKE_SA_TIMEOUT);
			break;
		}
		default:
			break;
	}
	charon->bus->ike_state_change(charon->bus, &this->public, state);
	this->state = state;
}

METHOD(ike_sa_t, reset, void,
	private_ike_sa_t *this)
{
	/*  the responder ID is reset, as peer may choose another one */
	if (this->ike_sa_id->is_initiator(this->ike_sa_id))
	{
		this->ike_sa_id->set_responder_spi(this->ike_sa_id, 0);
	}

	set_state(this, IKE_CREATED);

	flush_auth_cfgs(this);

	this->keymat->destroy(this->keymat);
	this->keymat = keymat_create(this->ike_sa_id->is_initiator(this->ike_sa_id));

	this->task_manager->reset(this->task_manager, 0, 0);
}

METHOD(ike_sa_t, get_keymat, keymat_t*,
	private_ike_sa_t *this)
{
	return this->keymat;
}

METHOD(ike_sa_t, set_virtual_ip, void,
	private_ike_sa_t *this, bool local, host_t *ip)
{
	if (local)
	{
		DBG1(DBG_IKE, "installing new virtual IP %H", ip);
		if (hydra->kernel_interface->add_ip(hydra->kernel_interface, ip,
											this->my_host) == SUCCESS)
		{
			if (this->my_virtual_ip)
			{
				DBG1(DBG_IKE, "removing old virtual IP %H", this->my_virtual_ip);
				hydra->kernel_interface->del_ip(hydra->kernel_interface,
												this->my_virtual_ip);
			}
			DESTROY_IF(this->my_virtual_ip);
			this->my_virtual_ip = ip->clone(ip);
		}
		else
		{
			DBG1(DBG_IKE, "installing virtual IP %H failed", ip);
			this->my_virtual_ip = NULL;
		}
	}
	else
	{
		DESTROY_IF(this->other_virtual_ip);
		this->other_virtual_ip = ip->clone(ip);
	}
}

METHOD(ike_sa_t, get_virtual_ip, host_t*,
	private_ike_sa_t *this, bool local)
{
	if (local)
	{
		return this->my_virtual_ip;
	}
	else
	{
		return this->other_virtual_ip;
	}
}

METHOD(ike_sa_t, add_additional_address, void,
	private_ike_sa_t *this, host_t *host)
{
	this->additional_addresses->insert_last(this->additional_addresses, host);
}

METHOD(ike_sa_t, create_additional_address_iterator, iterator_t*,
	private_ike_sa_t *this)
{
	return this->additional_addresses->create_iterator(
											this->additional_addresses, TRUE);
}

METHOD(ike_sa_t, has_mapping_changed, bool,
	private_ike_sa_t *this, chunk_t hash)
{
	if (this->nat_detection_dest.ptr == NULL)
	{
		this->nat_detection_dest = chunk_clone(hash);
		return FALSE;
	}
	if (chunk_equals(hash, this->nat_detection_dest))
	{
		return FALSE;
	}
	free(this->nat_detection_dest.ptr);
	this->nat_detection_dest = chunk_clone(hash);
	return TRUE;
}

METHOD(ike_sa_t, set_pending_updates, void,
	private_ike_sa_t *this, u_int32_t updates)
{
	this->pending_updates = updates;
}

METHOD(ike_sa_t, get_pending_updates, u_int32_t,
	private_ike_sa_t *this)
{
	return this->pending_updates;
}

METHOD(ike_sa_t, float_ports, void,
	   private_ike_sa_t *this)
{
	/* do not switch if we have a custom port from MOBIKE/NAT */
	if (this->my_host->get_port(this->my_host) == IKEV2_UDP_PORT)
	{
		this->my_host->set_port(this->my_host, IKEV2_NATT_PORT);
	}
	if (this->other_host->get_port(this->other_host) == IKEV2_UDP_PORT)
	{
		this->other_host->set_port(this->other_host, IKEV2_NATT_PORT);
	}
}

METHOD(ike_sa_t, update_hosts, void,
	private_ike_sa_t *this, host_t *me, host_t *other, bool force)
{
	bool update = FALSE;

	if (me == NULL)
	{
		me = this->my_host;
	}
	if (other == NULL)
	{
		other = this->other_host;
	}

	/* apply hosts on first received message */
	if (this->my_host->is_anyaddr(this->my_host) ||
		this->other_host->is_anyaddr(this->other_host))
	{
		set_my_host(this, me->clone(me));
		set_other_host(this, other->clone(other));
		update = TRUE;
	}
	else
	{
		/* update our address in any case */
		if (!me->equals(me, this->my_host))
		{
			set_my_host(this, me->clone(me));
			update = TRUE;
		}

		if (!other->equals(other, this->other_host))
		{
			/* update others adress if we are NOT NATed */
			if (force || !has_condition(this, COND_NAT_HERE))
			{
				set_other_host(this, other->clone(other));
				update = TRUE;
			}
		}
	}

	/* update all associated CHILD_SAs, if required */
	if (update)
	{
		iterator_t *iterator;
		child_sa_t *child_sa;

		iterator = this->child_sas->create_iterator(this->child_sas, TRUE);
		while (iterator->iterate(iterator, (void**)&child_sa))
		{
			if (child_sa->update(child_sa, this->my_host,
						this->other_host, this->my_virtual_ip,
						has_condition(this, COND_NAT_ANY)) == NOT_SUPPORTED)
			{
				this->public.rekey_child_sa(&this->public,
						child_sa->get_protocol(child_sa),
						child_sa->get_spi(child_sa, TRUE));
			}
		}
		iterator->destroy(iterator);
	}
}

METHOD(ike_sa_t, generate_message, status_t,
	private_ike_sa_t *this, message_t *message, packet_t **packet)
{
	if (message->is_encoded(message))
	{	/* already done */
		*packet = message->get_packet(message);
		return SUCCESS;
	}
	this->stats[STAT_OUTBOUND] = time_monotonic(NULL);
	message->set_ike_sa_id(message, this->ike_sa_id);
	charon->bus->message(charon->bus, message, FALSE);
	return message->generate(message,
				this->keymat->get_aead(this->keymat, FALSE), packet);
}

/**
 * send a notify back to the sender
 */
static void send_notify_response(private_ike_sa_t *this, message_t *request,
								 notify_type_t type, chunk_t data)
{
	message_t *response;
	packet_t *packet;

	response = message_create();
	response->set_exchange_type(response, request->get_exchange_type(request));
	response->set_request(response, FALSE);
	response->set_message_id(response, request->get_message_id(request));
	response->add_notify(response, FALSE, type, data);
	if (this->my_host->is_anyaddr(this->my_host))
	{
		this->my_host->destroy(this->my_host);
		this->my_host = request->get_destination(request);
		this->my_host = this->my_host->clone(this->my_host);
	}
	if (this->other_host->is_anyaddr(this->other_host))
	{
		this->other_host->destroy(this->other_host);
		this->other_host = request->get_source(request);
		this->other_host = this->other_host->clone(this->other_host);
	}
	response->set_source(response, this->my_host->clone(this->my_host));
	response->set_destination(response, this->other_host->clone(this->other_host));
	if (generate_message(this, response, &packet) == SUCCESS)
	{
		charon->sender->send(charon->sender, packet);
	}
	response->destroy(response);
}

METHOD(ike_sa_t, set_kmaddress, void,
	private_ike_sa_t *this, host_t *local, host_t *remote)
{
	DESTROY_IF(this->local_host);
	DESTROY_IF(this->remote_host);
	this->local_host = local->clone(local);
	this->remote_host = remote->clone(remote);
}

#ifdef ME
METHOD(ike_sa_t, act_as_mediation_server, void,
	private_ike_sa_t *this)
{
	charon->mediation_manager->update_sa_id(charon->mediation_manager,
			this->other_id, this->ike_sa_id);
	this->is_mediation_server = TRUE;
}

METHOD(ike_sa_t, get_server_reflexive_host, host_t*,
	private_ike_sa_t *this)
{
	return this->server_reflexive_host;
}

METHOD(ike_sa_t, set_server_reflexive_host, void,
	private_ike_sa_t *this, host_t *host)
{
	DESTROY_IF(this->server_reflexive_host);
	this->server_reflexive_host = host;
}

METHOD(ike_sa_t, get_connect_id, chunk_t,
	private_ike_sa_t *this)
{
	return this->connect_id;
}

METHOD(ike_sa_t, respond, status_t,
	private_ike_sa_t *this, identification_t *peer_id, chunk_t connect_id)
{
	ike_me_t *task = ike_me_create(&this->public, TRUE);
	task->respond(task, peer_id, connect_id);
	this->task_manager->queue_task(this->task_manager, (task_t*)task);
	return this->task_manager->initiate(this->task_manager);
}

METHOD(ike_sa_t, callback, status_t,
	private_ike_sa_t *this, identification_t *peer_id)
{
	ike_me_t *task = ike_me_create(&this->public, TRUE);
	task->callback(task, peer_id);
	this->task_manager->queue_task(this->task_manager, (task_t*)task);
	return this->task_manager->initiate(this->task_manager);
}

METHOD(ike_sa_t, relay, status_t,
	private_ike_sa_t *this, identification_t *requester, chunk_t connect_id,
	chunk_t connect_key, linked_list_t *endpoints, bool response)
{
	ike_me_t *task = ike_me_create(&this->public, TRUE);
	task->relay(task, requester, connect_id, connect_key, endpoints, response);
	this->task_manager->queue_task(this->task_manager, (task_t*)task);
	return this->task_manager->initiate(this->task_manager);
}

METHOD(ike_sa_t, initiate_mediation, status_t,
	private_ike_sa_t *this, peer_cfg_t *mediated_cfg)
{
	ike_me_t *task = ike_me_create(&this->public, TRUE);
	task->connect(task, mediated_cfg->get_peer_id(mediated_cfg));
	this->task_manager->queue_task(this->task_manager, (task_t*)task);
	return this->task_manager->initiate(this->task_manager);
}

METHOD(ike_sa_t, initiate_mediated, status_t,
	private_ike_sa_t *this, host_t *me, host_t *other, chunk_t connect_id)
{
	set_my_host(this, me->clone(me));
	set_other_host(this, other->clone(other));
	chunk_free(&this->connect_id);
	this->connect_id = chunk_clone(connect_id);
	return this->task_manager->initiate(this->task_manager);
}
#endif /* ME */

/**
 * Resolve DNS host in configuration
 */
static void resolve_hosts(private_ike_sa_t *this)
{
	host_t *host;

	if (this->remote_host)
	{
		host = this->remote_host->clone(this->remote_host);
		host->set_port(host, IKEV2_UDP_PORT);
	}
	else
	{
		host = host_create_from_dns(this->ike_cfg->get_other_addr(this->ike_cfg),
								0, this->ike_cfg->get_other_port(this->ike_cfg));
	}
	if (host)
	{
		set_other_host(this, host);
	}

	if (this->local_host)
	{
		host = this->local_host->clone(this->local_host);
		host->set_port(host, IKEV2_UDP_PORT);
	}
	else
	{
		int family = 0;

		/* use same address family as for other */
		if (!this->other_host->is_anyaddr(this->other_host))
		{
			family = this->other_host->get_family(this->other_host);
		}
		host = host_create_from_dns(this->ike_cfg->get_my_addr(this->ike_cfg),
							family, this->ike_cfg->get_my_port(this->ike_cfg));

		if (host && host->is_anyaddr(host) &&
			!this->other_host->is_anyaddr(this->other_host))
		{
			host->destroy(host);
			host = hydra->kernel_interface->get_source_addr(
							hydra->kernel_interface, this->other_host, NULL);
			if (host)
			{
				host->set_port(host, this->ike_cfg->get_my_port(this->ike_cfg));
			}
			else
			{	/* fallback to address family specific %any(6), if configured */
				host = host_create_from_dns(
								this->ike_cfg->get_my_addr(this->ike_cfg),
								0, this->ike_cfg->get_my_port(this->ike_cfg));
			}
		}
	}
	if (host)
	{
		set_my_host(this, host);
	}
}

METHOD(ike_sa_t, initiate, status_t,
	private_ike_sa_t *this, child_cfg_t *child_cfg, u_int32_t reqid,
	traffic_selector_t *tsi, traffic_selector_t *tsr)
{
	task_t *task;

	if (this->state == IKE_CREATED)
	{
		resolve_hosts(this);

		if (this->other_host->is_anyaddr(this->other_host)
#ifdef ME
			&& !this->peer_cfg->get_mediated_by(this->peer_cfg)
#endif /* ME */
			)
		{
			child_cfg->destroy(child_cfg);
			DBG1(DBG_IKE, "unable to initiate to %%any");
			return DESTROY_ME;
		}

		set_condition(this, COND_ORIGINAL_INITIATOR, TRUE);

		task = (task_t*)ike_vendor_create(&this->public, TRUE);
		this->task_manager->queue_task(this->task_manager, task);
		task = (task_t*)ike_init_create(&this->public, TRUE, NULL);
		this->task_manager->queue_task(this->task_manager, task);
		task = (task_t*)ike_natd_create(&this->public, TRUE);
		this->task_manager->queue_task(this->task_manager, task);
		task = (task_t*)ike_cert_pre_create(&this->public, TRUE);
		this->task_manager->queue_task(this->task_manager, task);
		task = (task_t*)ike_auth_create(&this->public, TRUE);
		this->task_manager->queue_task(this->task_manager, task);
		task = (task_t*)ike_cert_post_create(&this->public, TRUE);
		this->task_manager->queue_task(this->task_manager, task);
		task = (task_t*)ike_config_create(&this->public, TRUE);
		this->task_manager->queue_task(this->task_manager, task);
		task = (task_t*)ike_auth_lifetime_create(&this->public, TRUE);
		this->task_manager->queue_task(this->task_manager, task);
		if (this->peer_cfg->use_mobike(this->peer_cfg))
		{
			task = (task_t*)ike_mobike_create(&this->public, TRUE);
			this->task_manager->queue_task(this->task_manager, task);
		}
#ifdef ME
		task = (task_t*)ike_me_create(&this->public, TRUE);
		this->task_manager->queue_task(this->task_manager, task);
#endif /* ME */
	}

#ifdef ME
	if (this->peer_cfg->is_mediation(this->peer_cfg))
	{
		if (this->state == IKE_ESTABLISHED)
		{
			/* mediation connection is already established, retrigger state
			 * change to notify bus listeners */
			DBG1(DBG_IKE, "mediation connection is already up");
			set_state(this, IKE_ESTABLISHED);
		}
		DESTROY_IF(child_cfg);
	}
	else
#endif /* ME */
	{
		/* normal IKE_SA with CHILD_SA */
		task = (task_t*)child_create_create(&this->public, child_cfg, FALSE,
											tsi, tsr);
		child_cfg->destroy(child_cfg);
		if (reqid)
		{
			child_create_t *child_create = (child_create_t*)task;
			child_create->use_reqid(child_create, reqid);
		}
		this->task_manager->queue_task(this->task_manager, task);

#ifdef ME
		if (this->peer_cfg->get_mediated_by(this->peer_cfg))
		{
			/* mediated connection, initiate mediation process */
			job_t *job = (job_t*)initiate_mediation_job_create(this->ike_sa_id);
			lib->processor->queue_job(lib->processor, job);
			return SUCCESS;
		}
#endif /* ME */
	}

	return this->task_manager->initiate(this->task_manager);
}

METHOD(ike_sa_t, process_message, status_t,
	private_ike_sa_t *this, message_t *message)
{
	status_t status;
	bool is_request;
	u_int8_t type = 0;

	if (this->state == IKE_PASSIVE)
	{	/* do not handle messages in passive state */
		return FAILED;
	}

	is_request = message->get_request(message);

	status = message->parse_body(message,
								 this->keymat->get_aead(this->keymat, TRUE));
	if (status == SUCCESS)
	{	/* check for unsupported critical payloads */
		enumerator_t *enumerator;
		unknown_payload_t *unknown;
		payload_t *payload;

		enumerator = message->create_payload_enumerator(message);
		while (enumerator->enumerate(enumerator, &payload))
		{
			unknown = (unknown_payload_t*)payload;
			type = payload->get_type(payload);
			if (!payload_is_known(type) &&
				unknown->is_critical(unknown))
			{
				DBG1(DBG_ENC, "payload type %N is not supported, "
					 "but its critical!", payload_type_names, type);
				status = NOT_SUPPORTED;
			}
		}
		enumerator->destroy(enumerator);
	}
	if (status != SUCCESS)
	{
		if (is_request)
		{
			switch (status)
			{
				case NOT_SUPPORTED:
					DBG1(DBG_IKE, "critical unknown payloads found");
					if (is_request)
					{
						send_notify_response(this, message,
											 UNSUPPORTED_CRITICAL_PAYLOAD,
											 chunk_from_thing(type));
						this->task_manager->incr_mid(this->task_manager, FALSE);
					}
					break;
				case PARSE_ERROR:
					DBG1(DBG_IKE, "message parsing failed");
					if (is_request)
					{
						send_notify_response(this, message,
											 INVALID_SYNTAX, chunk_empty);
						this->task_manager->incr_mid(this->task_manager, FALSE);
					}
					break;
				case VERIFY_ERROR:
					DBG1(DBG_IKE, "message verification failed");
					if (is_request)
					{
						send_notify_response(this, message,
											 INVALID_SYNTAX, chunk_empty);
						this->task_manager->incr_mid(this->task_manager, FALSE);
					}
					break;
				case FAILED:
					DBG1(DBG_IKE, "integrity check failed");
					/* ignored */
					break;
				case INVALID_STATE:
					DBG1(DBG_IKE, "found encrypted message, but no keys available");
				default:
					break;
			}
		}
		DBG1(DBG_IKE, "%N %s with message ID %d processing failed",
			 exchange_type_names, message->get_exchange_type(message),
			 message->get_request(message) ? "request" : "response",
			 message->get_message_id(message));

		if (this->state == IKE_CREATED)
		{	/* invalid initiation attempt, close SA */
			return DESTROY_ME;
		}
	}
	else
	{
		/* if this IKE_SA is virgin, we check for a config */
		if (this->ike_cfg == NULL)
		{
			job_t *job;
			host_t *me = message->get_destination(message),
				   *other = message->get_source(message);
			this->ike_cfg = charon->backends->get_ike_cfg(charon->backends,
														  me, other);
			if (this->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_response(this, message,
									 NO_PROPOSAL_CHOSEN, chunk_empty);
				return DESTROY_ME;
			}
			/* add a timeout if peer does not establish it completely */
			job = (job_t*)delete_ike_sa_job_create(this->ike_sa_id, FALSE);
			lib->scheduler->schedule_job(lib->scheduler, job,
										 HALF_OPEN_IKE_SA_TIMEOUT);
		}
		this->stats[STAT_INBOUND] = time_monotonic(NULL);
		status = this->task_manager->process_message(this->task_manager,
													 message);
		if (message->get_exchange_type(message) == IKE_AUTH &&
			this->state == IKE_ESTABLISHED &&
			lib->settings->get_bool(lib->settings,
									"charon.flush_auth_cfg", FALSE))
		{	/* authentication completed */
			flush_auth_cfgs(this);
		}
	}
	return status;
}

METHOD(ike_sa_t, get_id, ike_sa_id_t*,
	private_ike_sa_t *this)
{
	return this->ike_sa_id;
}

METHOD(ike_sa_t, get_my_id, identification_t*,
	private_ike_sa_t *this)
{
	return this->my_id;
}

METHOD(ike_sa_t, set_my_id, void,
	private_ike_sa_t *this, identification_t *me)
{
	DESTROY_IF(this->my_id);
	this->my_id = me;
}

METHOD(ike_sa_t, get_other_id, identification_t*,
	private_ike_sa_t *this)
{
	return this->other_id;
}

METHOD(ike_sa_t, get_other_eap_id, identification_t*,
	private_ike_sa_t *this)
{
	identification_t *id = NULL, *current;
	enumerator_t *enumerator;
	auth_cfg_t *cfg;

	enumerator = this->other_auths->create_enumerator(this->other_auths);
	while (enumerator->enumerate(enumerator, &cfg))
	{
		/* prefer EAP-Identity of last round */
		current = cfg->get(cfg, AUTH_RULE_EAP_IDENTITY);
		if (!current || current->get_type(current) == ID_ANY)
		{
			current = cfg->get(cfg, AUTH_RULE_IDENTITY);
		}
		if (current && current->get_type(current) != ID_ANY)
		{
			id = current;
			continue;
		}
	}
	enumerator->destroy(enumerator);
	if (id)
	{
		return id;
	}
	return this->other_id;
}

METHOD(ike_sa_t, set_other_id, void,
	private_ike_sa_t *this, identification_t *other)
{
	DESTROY_IF(this->other_id);
	this->other_id = other;
}

METHOD(ike_sa_t, add_child_sa, void,
	private_ike_sa_t *this, child_sa_t *child_sa)
{
	this->child_sas->insert_last(this->child_sas, child_sa);
}

METHOD(ike_sa_t, get_child_sa, child_sa_t*,
	private_ike_sa_t *this, protocol_id_t protocol, u_int32_t spi, bool inbound)
{
	iterator_t *iterator;
	child_sa_t *current, *found = NULL;

	iterator = this->child_sas->create_iterator(this->child_sas, TRUE);
	while (iterator->iterate(iterator, (void**)&current))
	{
		if (current->get_spi(current, inbound) == spi &&
			current->get_protocol(current) == protocol)
		{
			found = current;
		}
	}
	iterator->destroy(iterator);
	return found;
}

METHOD(ike_sa_t, create_child_sa_iterator, iterator_t*,
	private_ike_sa_t *this)
{
	return this->child_sas->create_iterator(this->child_sas, TRUE);
}

METHOD(ike_sa_t, rekey_child_sa, status_t,
	private_ike_sa_t *this, protocol_id_t protocol, u_int32_t spi)
{
	child_rekey_t *child_rekey;

	child_rekey = child_rekey_create(&this->public, protocol, spi);
	this->task_manager->queue_task(this->task_manager, &child_rekey->task);
	return this->task_manager->initiate(this->task_manager);
}

METHOD(ike_sa_t, delete_child_sa, status_t,
	private_ike_sa_t *this, protocol_id_t protocol, u_int32_t spi)
{
	child_delete_t *child_delete;

	child_delete = child_delete_create(&this->public, protocol, spi);
	this->task_manager->queue_task(this->task_manager, &child_delete->task);
	return this->task_manager->initiate(this->task_manager);
}

METHOD(ike_sa_t, destroy_child_sa, status_t,
	private_ike_sa_t *this, protocol_id_t protocol, u_int32_t spi)
{
	iterator_t *iterator;
	child_sa_t *child_sa;
	status_t status = NOT_FOUND;

	iterator = this->child_sas->create_iterator(this->child_sas, TRUE);
	while (iterator->iterate(iterator, (void**)&child_sa))
	{
		if (child_sa->get_protocol(child_sa) == protocol &&
			child_sa->get_spi(child_sa, TRUE) == spi)
		{
			child_sa->destroy(child_sa);
			iterator->remove(iterator);
			status = SUCCESS;
			break;
		}
	}
	iterator->destroy(iterator);
	return status;
}

METHOD(ike_sa_t, delete_, status_t,
	private_ike_sa_t *this)
{
	ike_delete_t *ike_delete;

	switch (this->state)
	{
		case IKE_ESTABLISHED:
		case IKE_REKEYING:
			ike_delete = ike_delete_create(&this->public, TRUE);
			this->task_manager->queue_task(this->task_manager, &ike_delete->task);
			return this->task_manager->initiate(this->task_manager);
		case IKE_CREATED:
			DBG1(DBG_IKE, "deleting unestablished IKE_SA");
			break;
		case IKE_PASSIVE:
			break;
		default:
			DBG1(DBG_IKE, "destroying IKE_SA in state %N "
				"without notification", ike_sa_state_names, this->state);
			charon->bus->ike_updown(charon->bus, &this->public, FALSE);
			break;
	}
	return DESTROY_ME;
}

METHOD(ike_sa_t, rekey, status_t,
	private_ike_sa_t *this)
{
	ike_rekey_t *ike_rekey;

	ike_rekey = ike_rekey_create(&this->public, TRUE);

	this->task_manager->queue_task(this->task_manager, &ike_rekey->task);
	return this->task_manager->initiate(this->task_manager);
}

METHOD(ike_sa_t, reauth, status_t,
	private_ike_sa_t *this)
{
	task_t *task;

	/* we can't reauthenticate as responder when we use EAP or virtual IPs.
	 * If the peer does not support RFC4478, there is no way to keep the
	 * IKE_SA up. */
	if (!has_condition(this, COND_ORIGINAL_INITIATOR))
	{
		DBG1(DBG_IKE, "initiator did not reauthenticate as requested");
		if (this->other_virtual_ip != NULL ||
			has_condition(this, COND_EAP_AUTHENTICATED)
#ifdef ME
			/* as mediation server we too cannot reauth the IKE_SA */
			|| this->is_mediation_server
#endif /* ME */
			)
		{
			time_t now = time_monotonic(NULL);

			DBG1(DBG_IKE, "IKE_SA will timeout in %V",
				 &now, &this->stats[STAT_DELETE]);
			return FAILED;
		}
		else
		{
			DBG1(DBG_IKE, "reauthenticating actively");
		}
	}
	task = (task_t*)ike_reauth_create(&this->public);
	this->task_manager->queue_task(this->task_manager, task);

	return this->task_manager->initiate(this->task_manager);
}

METHOD(ike_sa_t, reestablish, status_t,
	private_ike_sa_t *this)
{
	ike_sa_t *new;
	host_t *host;
	action_t action;
	iterator_t *iterator;
	child_sa_t *child_sa;
	child_cfg_t *child_cfg;
	bool restart = FALSE;
	status_t status = FAILED;

	/* check if we have children to keep up at all */
	iterator = create_child_sa_iterator(this);
	while (iterator->iterate(iterator, (void**)&child_sa))
	{
		if (this->state == IKE_DELETING)
		{
			action = child_sa->get_close_action(child_sa);
		}
		else
		{
			action = child_sa->get_dpd_action(child_sa);
		}
		switch (action)
		{
			case ACTION_RESTART:
				restart = TRUE;
				break;
			case ACTION_ROUTE:
				charon->traps->install(charon->traps, this->peer_cfg,
									   child_sa->get_config(child_sa));
				break;
			default:
				break;
		}
	}
	iterator->destroy(iterator);
#ifdef ME
	/* mediation connections have no children, keep them up anyway */
	if (this->peer_cfg->is_mediation(this->peer_cfg))
	{
		restart = TRUE;
	}
#endif /* ME */
	if (!restart)
	{
		return FAILED;
	}

	/* check if we are able to reestablish this IKE_SA */
	if (!has_condition(this, COND_ORIGINAL_INITIATOR) &&
		(this->other_virtual_ip != NULL ||
		 has_condition(this, COND_EAP_AUTHENTICATED)
#ifdef ME
		 || this->is_mediation_server
#endif /* ME */
		))
	{
		DBG1(DBG_IKE, "unable to reestablish IKE_SA due to asymmetric setup");
		return FAILED;
	}

	new = charon->ike_sa_manager->checkout_new(charon->ike_sa_manager, TRUE);
	new->set_peer_cfg(new, this->peer_cfg);
	host = this->other_host;
	new->set_other_host(new, host->clone(host));
	host = this->my_host;
	new->set_my_host(new, host->clone(host));
	/* if we already have a virtual IP, we reuse it */
	host = this->my_virtual_ip;
	if (host)
	{
		new->set_virtual_ip(new, TRUE, host);
	}

#ifdef ME
	if (this->peer_cfg->is_mediation(this->peer_cfg))
	{
		status = new->initiate(new, NULL, 0, NULL, NULL);
	}
	else
#endif /* ME */
	{
		iterator = create_child_sa_iterator(this);
		while (iterator->iterate(iterator, (void**)&child_sa))
		{
			if (this->state == IKE_DELETING)
			{
				action = child_sa->get_close_action(child_sa);
			}
			else
			{
				action = child_sa->get_dpd_action(child_sa);
			}
			switch (action)
			{
				case ACTION_RESTART:
					child_cfg = child_sa->get_config(child_sa);
					DBG1(DBG_IKE, "restarting CHILD_SA %s",
						 child_cfg->get_name(child_cfg));
					child_cfg->get_ref(child_cfg);
					status = new->initiate(new, child_cfg, 0, NULL, NULL);
					break;
				default:
					continue;
			}
			if (status == DESTROY_ME)
			{
				break;
			}
		}
		iterator->destroy(iterator);
	}

	if (status == DESTROY_ME)
	{
		charon->ike_sa_manager->checkin_and_destroy(charon->ike_sa_manager, new);
		status = FAILED;
	}
	else
	{
		charon->ike_sa_manager->checkin(charon->ike_sa_manager, new);
		status = SUCCESS;
	}
	charon->bus->set_sa(charon->bus, &this->public);
	return status;
}

/**
 * Requeue the IKE_SA_INIT tasks for initiation, if required
 */
static void requeue_init_tasks(private_ike_sa_t *this)
{
	enumerator_t *enumerator;
	bool has_init = FALSE;
	task_t *task;

	/* if we have advanced to IKE_AUTH, the IKE_INIT and related tasks
	 * have already completed. Recreate them if necessary. */
	enumerator = this->task_manager->create_task_enumerator(
										this->task_manager, TASK_QUEUE_QUEUED);
	while (enumerator->enumerate(enumerator, &task))
	{
		if (task->get_type(task) == IKE_INIT)
		{
			has_init = TRUE;
			break;
		}
	}
	enumerator->destroy(enumerator);

	if (!has_init)
	{
		task = (task_t*)ike_vendor_create(&this->public, TRUE);
		this->task_manager->queue_task(this->task_manager, task);
		task = (task_t*)ike_natd_create(&this->public, TRUE);
		this->task_manager->queue_task(this->task_manager, task);
		task = (task_t*)ike_init_create(&this->public, TRUE, NULL);
		this->task_manager->queue_task(this->task_manager, task);
	}
}

METHOD(ike_sa_t, retransmit, status_t,
	private_ike_sa_t *this, u_int32_t message_id)
{
	this->stats[STAT_OUTBOUND] = time_monotonic(NULL);
	if (this->task_manager->retransmit(this->task_manager, message_id) != SUCCESS)
	{
		/* send a proper signal to brief interested bus listeners */
		switch (this->state)
		{
			case IKE_CONNECTING:
			{
				/* retry IKE_SA_INIT if we have multiple keyingtries */
				u_int32_t tries = this->peer_cfg->get_keyingtries(this->peer_cfg);
				this->keyingtry++;
				if (tries == 0 || tries > this->keyingtry)
				{
					DBG1(DBG_IKE, "peer not responding, trying again (%d/%d)",
						 this->keyingtry + 1, tries);
					reset(this);
					requeue_init_tasks(this);
					return this->task_manager->initiate(this->task_manager);
				}
				DBG1(DBG_IKE, "establishing IKE_SA failed, peer not responding");
				break;
			}
			case IKE_DELETING:
				DBG1(DBG_IKE, "proper IKE_SA delete failed, peer not responding");
				break;
			case IKE_REKEYING:
				DBG1(DBG_IKE, "rekeying IKE_SA failed, peer not responding");
				/* FALL */
			default:
				reestablish(this);
				break;
		}
		return DESTROY_ME;
	}
	return SUCCESS;
}

METHOD(ike_sa_t, set_auth_lifetime, void,
	private_ike_sa_t *this, u_int32_t lifetime)
{
	u_int32_t reduction = this->peer_cfg->get_over_time(this->peer_cfg);
	u_int32_t reauth_time = time_monotonic(NULL) + lifetime - reduction;

	if (lifetime < reduction)
	{
		DBG1(DBG_IKE, "received AUTH_LIFETIME of %ds, starting reauthentication",
			 lifetime);
		lib->processor->queue_job(lib->processor,
					(job_t*)rekey_ike_sa_job_create(this->ike_sa_id, TRUE));
	}
	else if (this->stats[STAT_REAUTH] == 0 ||
			 this->stats[STAT_REAUTH] > reauth_time)
	{
		this->stats[STAT_REAUTH] = reauth_time;
		DBG1(DBG_IKE, "received AUTH_LIFETIME of %ds, scheduling reauthentication"
			 " in %ds", lifetime, lifetime - reduction);
		lib->scheduler->schedule_job(lib->scheduler,
						(job_t*)rekey_ike_sa_job_create(this->ike_sa_id, TRUE),
						lifetime - reduction);
	}
	else
	{
		DBG1(DBG_IKE, "received AUTH_LIFETIME of %ds, "
			 "reauthentication already scheduled in %ds", lifetime,
			 this->stats[STAT_REAUTH] - time_monotonic(NULL));
	}
}

/**
 * Check if the current combination of source and destination address is still
 * valid.
 */
static bool is_current_path_valid(private_ike_sa_t *this)
{
	bool valid = FALSE;
	host_t *src;
	src = hydra->kernel_interface->get_source_addr(hydra->kernel_interface,
											this->other_host, this->my_host);
	if (src)
	{
		if (src->ip_equals(src, this->my_host))
		{
			valid = TRUE;
		}
		src->destroy(src);
	}
	return valid;
}

/**
 * Check if we have any path avialable for this IKE SA.
 */
static bool is_any_path_valid(private_ike_sa_t *this)
{
	bool valid = FALSE;
	enumerator_t *enumerator;
	host_t *src, *addr;
	DBG1(DBG_IKE, "old path is not available anymore, try to find another");
	src = hydra->kernel_interface->get_source_addr(hydra->kernel_interface,
												   this->other_host, NULL);
	if (!src)
	{
		enumerator = this->additional_addresses->create_enumerator(
												this->additional_addresses);
		while (enumerator->enumerate(enumerator, &addr))
		{
			DBG1(DBG_IKE, "looking for a route to %H ...", addr);
			src = hydra->kernel_interface->get_source_addr(
									hydra->kernel_interface, addr, NULL);
			if (src)
			{
				break;
			}
		}
		enumerator->destroy(enumerator);
	}
	if (src)
	{
		valid = TRUE;
		src->destroy(src);
	}
	return valid;
}

METHOD(ike_sa_t, roam, status_t,
	private_ike_sa_t *this, bool address)
{
	ike_mobike_t *mobike;

	switch (this->state)
	{
		case IKE_CREATED:
		case IKE_DELETING:
		case IKE_DESTROYING:
		case IKE_PASSIVE:
			return SUCCESS;
		default:
			break;
	}

	/* keep existing path if possible */
	if (is_current_path_valid(this))
	{
		DBG2(DBG_IKE, "keeping connection path %H - %H",
			 this->my_host, this->other_host);
		set_condition(this, COND_STALE, FALSE);

		if (supports_extension(this, EXT_MOBIKE) && address)
		{	/* if any addresses changed, send an updated list */
			DBG1(DBG_IKE, "sending address list update using MOBIKE");
			mobike = ike_mobike_create(&this->public, TRUE);
			mobike->addresses(mobike);
			this->task_manager->queue_task(this->task_manager,
										   (task_t*)mobike);
			return this->task_manager->initiate(this->task_manager);
		}
		return SUCCESS;
	}

	if (!is_any_path_valid(this))
	{
		DBG1(DBG_IKE, "no route found to reach %H, MOBIKE update deferred",
			 this->other_host);
		set_condition(this, COND_STALE, TRUE);
		return SUCCESS;
	}
	set_condition(this, COND_STALE, FALSE);

	/* update addresses with mobike, if supported ... */
	if (supports_extension(this, EXT_MOBIKE))
	{
		if (!has_condition(this, COND_ORIGINAL_INITIATOR))
		{	/* responder updates the peer about changed address config */
			DBG1(DBG_IKE, "sending address list update using MOBIKE, "
				 "implicitly requesting an address change");
			address = TRUE;
		}
		else
		{
			DBG1(DBG_IKE, "requesting address change using MOBIKE");
		}
		mobike = ike_mobike_create(&this->public, TRUE);
		mobike->roam(mobike, address);
		this->task_manager->queue_task(this->task_manager, (task_t*)mobike);
		return this->task_manager->initiate(this->task_manager);
	}

	/* ... reauth if not */
	if (!has_condition(this, COND_ORIGINAL_INITIATOR))
	{	/* responder does not reauthenticate */
		set_condition(this, COND_STALE, TRUE);
		return SUCCESS;
	}
	DBG1(DBG_IKE, "reauthenticating IKE_SA due to address change");
	return reauth(this);
}

METHOD(ike_sa_t, add_configuration_attribute, void,
	private_ike_sa_t *this, attribute_handler_t *handler,
	configuration_attribute_type_t type, chunk_t data)
{
	attribute_entry_t *entry = malloc_thing(attribute_entry_t);

	entry->handler = handler;
	entry->type = type;
	entry->data = chunk_clone(data);

	this->attributes->insert_last(this->attributes, entry);
}

METHOD(ike_sa_t, create_task_enumerator, enumerator_t*,
	private_ike_sa_t *this, task_queue_t queue)
{
	return this->task_manager->create_task_enumerator(this->task_manager, queue);
}

METHOD(ike_sa_t, inherit, void,
	private_ike_sa_t *this, ike_sa_t *other_public)
{
	private_ike_sa_t *other = (private_ike_sa_t*)other_public;
	child_sa_t *child_sa;
	attribute_entry_t *entry;

	/* apply hosts and ids */
	this->my_host->destroy(this->my_host);
	this->other_host->destroy(this->other_host);
	this->my_id->destroy(this->my_id);
	this->other_id->destroy(this->other_id);
	this->my_host = other->my_host->clone(other->my_host);
	this->other_host = other->other_host->clone(other->other_host);
	this->my_id = other->my_id->clone(other->my_id);
	this->other_id = other->other_id->clone(other->other_id);

	/* apply virtual assigned IPs... */
	if (other->my_virtual_ip)
	{
		this->my_virtual_ip = other->my_virtual_ip;
		other->my_virtual_ip = NULL;
	}
	if (other->other_virtual_ip)
	{
		this->other_virtual_ip = other->other_virtual_ip;
		other->other_virtual_ip = NULL;
	}

	/* ... and configuration attributes */
	while (other->attributes->remove_last(other->attributes,
										  (void**)&entry) == SUCCESS)
	{
		this->attributes->insert_first(this->attributes, entry);
	}

	/* inherit all conditions */
	this->conditions = other->conditions;
	if (this->conditions & COND_NAT_HERE)
	{
		send_keepalive(this);
	}

#ifdef ME
	if (other->is_mediation_server)
	{
		act_as_mediation_server(this);
	}
	else if (other->server_reflexive_host)
	{
		this->server_reflexive_host = other->server_reflexive_host->clone(
				other->server_reflexive_host);
	}
#endif /* ME */

	/* adopt all children */
	while (other->child_sas->remove_last(other->child_sas,
										 (void**)&child_sa) == SUCCESS)
	{
		this->child_sas->insert_first(this->child_sas, (void*)child_sa);
	}

	/* move pending tasks to the new IKE_SA */
	this->task_manager->adopt_tasks(this->task_manager, other->task_manager);

	/* reauthentication timeout survives a rekeying */
	if (other->stats[STAT_REAUTH])
	{
		time_t reauth, delete, now = time_monotonic(NULL);

		this->stats[STAT_REAUTH] = other->stats[STAT_REAUTH];
		reauth = this->stats[STAT_REAUTH] - now;
		delete = reauth + this->peer_cfg->get_over_time(this->peer_cfg);
		this->stats[STAT_DELETE] = this->stats[STAT_REAUTH] + delete;
		DBG1(DBG_IKE, "rescheduling reauthentication in %ds after rekeying, "
			 "lifetime reduced to %ds", reauth, delete);
		lib->scheduler->schedule_job(lib->scheduler,
				(job_t*)rekey_ike_sa_job_create(this->ike_sa_id, TRUE), reauth);
		lib->scheduler->schedule_job(lib->scheduler,
				(job_t*)delete_ike_sa_job_create(this->ike_sa_id, TRUE), delete);
	}
}

METHOD(ike_sa_t, destroy, void,
	private_ike_sa_t *this)
{
	attribute_entry_t *entry;

	charon->bus->set_sa(charon->bus, &this->public);

	set_state(this, IKE_DESTROYING);
	this->task_manager->destroy(this->task_manager);

	/* remove attributes first, as we pass the IKE_SA to the handler */
	while (this->attributes->remove_last(this->attributes,
										 (void**)&entry) == SUCCESS)
	{
		hydra->attributes->release(hydra->attributes, entry->handler,
								   this->other_id, entry->type, entry->data);
		free(entry->data.ptr);
		free(entry);
	}
	this->attributes->destroy(this->attributes);

	this->child_sas->destroy_offset(this->child_sas, offsetof(child_sa_t, destroy));

	/* unset SA after here to avoid usage by the listeners */
	charon->bus->set_sa(charon->bus, NULL);

	this->keymat->destroy(this->keymat);

	if (this->my_virtual_ip)
	{
		hydra->kernel_interface->del_ip(hydra->kernel_interface,
										this->my_virtual_ip);
		this->my_virtual_ip->destroy(this->my_virtual_ip);
	}
	if (this->other_virtual_ip)
	{
		if (this->peer_cfg && this->peer_cfg->get_pool(this->peer_cfg))
		{
			hydra->attributes->release_address(hydra->attributes,
							this->peer_cfg->get_pool(this->peer_cfg),
							this->other_virtual_ip, get_other_eap_id(this));
		}
		this->other_virtual_ip->destroy(this->other_virtual_ip);
	}
	this->additional_addresses->destroy_offset(this->additional_addresses,
													offsetof(host_t, destroy));
#ifdef ME
	if (this->is_mediation_server)
	{
		charon->mediation_manager->remove(charon->mediation_manager,
										  this->ike_sa_id);
	}
	DESTROY_IF(this->server_reflexive_host);
	chunk_free(&this->connect_id);
#endif /* ME */
	free(this->nat_detection_dest.ptr);

	DESTROY_IF(this->my_host);
	DESTROY_IF(this->other_host);
	DESTROY_IF(this->my_id);
	DESTROY_IF(this->other_id);
	DESTROY_IF(this->local_host);
	DESTROY_IF(this->remote_host);

	DESTROY_IF(this->ike_cfg);
	DESTROY_IF(this->peer_cfg);
	DESTROY_IF(this->proposal);
	this->my_auth->destroy(this->my_auth);
	this->other_auth->destroy(this->other_auth);
	this->my_auths->destroy_offset(this->my_auths,
								   offsetof(auth_cfg_t, destroy));
	this->other_auths->destroy_offset(this->other_auths,
									  offsetof(auth_cfg_t, destroy));

	this->ike_sa_id->destroy(this->ike_sa_id);
	free(this);
}

/*
 * Described in header.
 */
ike_sa_t * ike_sa_create(ike_sa_id_t *ike_sa_id)
{
	private_ike_sa_t *this;
	static u_int32_t unique_id = 0;

	INIT(this,
		.public = {
			.get_state = _get_state,
			.set_state = _set_state,
			.get_name = _get_name,
			.get_statistic = _get_statistic,
			.process_message = _process_message,
			.initiate = _initiate,
			.get_ike_cfg = _get_ike_cfg,
			.set_ike_cfg = _set_ike_cfg,
			.get_peer_cfg = _get_peer_cfg,
			.set_peer_cfg = _set_peer_cfg,
			.get_auth_cfg = _get_auth_cfg,
			.create_auth_cfg_enumerator = _create_auth_cfg_enumerator,
			.add_auth_cfg = _add_auth_cfg,
			.get_proposal = _get_proposal,
			.set_proposal = _set_proposal,
			.get_id = _get_id,
			.get_my_host = _get_my_host,
			.set_my_host = _set_my_host,
			.get_other_host = _get_other_host,
			.set_other_host = _set_other_host,
			.set_message_id = _set_message_id,
			.float_ports = _float_ports,
			.update_hosts = _update_hosts,
			.get_my_id = _get_my_id,
			.set_my_id = _set_my_id,
			.get_other_id = _get_other_id,
			.set_other_id = _set_other_id,
			.get_other_eap_id = _get_other_eap_id,
			.enable_extension = _enable_extension,
			.supports_extension = _supports_extension,
			.set_condition = _set_condition,
			.has_condition = _has_condition,
			.set_pending_updates = _set_pending_updates,
			.get_pending_updates = _get_pending_updates,
			.create_additional_address_iterator = _create_additional_address_iterator,
			.add_additional_address = _add_additional_address,
			.has_mapping_changed = _has_mapping_changed,
			.retransmit = _retransmit,
			.delete = _delete_,
			.destroy = _destroy,
			.send_dpd = _send_dpd,
			.send_keepalive = _send_keepalive,
			.get_keymat = _get_keymat,
			.add_child_sa = _add_child_sa,
			.get_child_sa = _get_child_sa,
			.create_child_sa_iterator = _create_child_sa_iterator,
			.rekey_child_sa = _rekey_child_sa,
			.delete_child_sa = _delete_child_sa,
			.destroy_child_sa = _destroy_child_sa,
			.rekey = _rekey,
			.reauth = _reauth,
			.reestablish = _reestablish,
			.set_auth_lifetime = _set_auth_lifetime,
			.roam = _roam,
			.inherit = _inherit,
			.generate_message = _generate_message,
			.reset = _reset,
			.get_unique_id = _get_unique_id,
			.set_virtual_ip = _set_virtual_ip,
			.get_virtual_ip = _get_virtual_ip,
			.add_configuration_attribute = _add_configuration_attribute,
			.set_kmaddress = _set_kmaddress,
			.create_task_enumerator = _create_task_enumerator,
#ifdef ME
			.act_as_mediation_server = _act_as_mediation_server,
			.get_server_reflexive_host = _get_server_reflexive_host,
			.set_server_reflexive_host = _set_server_reflexive_host,
			.get_connect_id = _get_connect_id,
			.initiate_mediation = _initiate_mediation,
			.initiate_mediated = _initiate_mediated,
			.relay = _relay,
			.callback = _callback,
			.respond = _respond,
#endif /* ME */
		},
		.ike_sa_id = ike_sa_id->clone(ike_sa_id),
		.child_sas = linked_list_create(),
		.my_host = host_create_any(AF_INET),
		.other_host = host_create_any(AF_INET),
		.my_id = identification_create_from_encoding(ID_ANY, chunk_empty),
		.other_id = identification_create_from_encoding(ID_ANY, chunk_empty),
		.keymat = keymat_create(ike_sa_id->is_initiator(ike_sa_id)),
		.state = IKE_CREATED,
		.stats[STAT_INBOUND] = time_monotonic(NULL),
		.stats[STAT_OUTBOUND] = time_monotonic(NULL),
		.my_auth = auth_cfg_create(),
		.other_auth = auth_cfg_create(),
		.my_auths = linked_list_create(),
		.other_auths = linked_list_create(),
		.task_manager = task_manager_create(&this->public),
		.unique_id = ++unique_id,
		.additional_addresses = linked_list_create(),
		.attributes = linked_list_create(),
		.keepalive_interval = lib->settings->get_time(lib->settings,
									"charon.keep_alive", KEEPALIVE_INTERVAL),
	);
	this->my_host->set_port(this->my_host, IKEV2_UDP_PORT);

	return &this->public;
}