ikev2: Return to the original host if connection fails after redirection

[thirdparty/strongswan.git] / src / libcharon / sa / ike_sa.c

/*
 * Copyright (C) 2006-2020 Tobias Brunner
 * Copyright (C) 2006 Daniel Roethlisberger
 * Copyright (C) 2005-2009 Martin Willi
 * Copyright (C) 2005 Jan Hutter
 * HSR 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.
 */

/*
 * Copyright (c) 2014 Volker Rümelin
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include <string.h>
#include <sys/stat.h>
#include <errno.h>
#include <time.h>

#include "ike_sa.h"

#include <library.h>
#include <daemon.h>
#include <collections/array.h>
#include <utils/lexparser.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 <processing/jobs/retry_initiate_job.h>
#include <sa/ikev2/tasks/ike_auth_lifetime.h>
#include <sa/ikev2/tasks/ike_reauth_complete.h>
#include <sa/ikev2/tasks/ike_redirect.h>
#include <credentials/sets/auth_cfg_wrapper.h>

#ifdef ME
#include <sa/ikev2/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",
	"REKEYED",
	"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;

	/**
	 * IKE version of this SA.
	 */
	ike_version_t version;

	/**
	 * unique numerical ID for this IKE_SA.
	 */
	uint32_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
	 */
	auth_cfg_t *my_auth;

	/**
	 * currently used authentication constraints, remote
	 */
	auth_cfg_t *other_auth;

	/**
	 * Array of completed local authentication rounds (as auth_cfg_t)
	 */
	array_t *my_auths;

	/**
	 * Array of completed remote authentication rounds (as auth_cfg_t)
	 */
	array_t *other_auths;

	/**
	 * 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;

	/**
	 * Array containing the child sa's of the current IKE_SA.
	 */
	array_t *child_sas;

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

	/**
	 * Virtual IPs on local host
	 */
	array_t *my_vips;

	/**
	 * Virtual IPs on remote host
	 */
	array_t *other_vips;

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

	/**
	 * list of peer's addresses, additional ones transmitted via MOBIKE
	 */
	array_t *peer_addresses;

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

	/**
	 * NAT keep alive interval
	 */
	uint32_t keepalive_interval;

	/**
	 * The scheduled keep alive job, if any
	 */
	send_keepalive_job_t *keepalive_job;

	/**
	 * interval for retries during initiation (e.g. if DNS resolution failed),
	 * 0 to disable (default)
	 */
	uint32_t retry_initiate_interval;

	/**
	 * TRUE if a retry_initiate_job has been queued
	 */
	bool retry_initiate_queued;

	/**
	 * Timestamps for this IKE_SA
	 */
	uint32_t stats[STAT_MAX];

	/**
	 * how many times we have retried so far (keyingtries)
	 */
	uint32_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;

	/**
	 * Flush auth configs once established?
	 */
	bool flush_auth_cfg;

	/**
	 * Maximum length of a single fragment, 0 for address-specific defaults
	 */
	size_t fragment_size;

	/**
	 * Whether to follow IKEv2 redirects
	 */
	bool follow_redirects;

	/**
	 * Original gateway address from which we got redirected
	 */
	host_t *redirected_from;

	/**
	 * Timestamps of redirect attempts to handle loops
	 */
	array_t *redirected_at;

	/**
	 * Inbound interface ID
	 */
	uint32_t if_id_in;

	/**
	 * Outbound interface ID
	 */
	uint32_t if_id_out;
};

/**
 * 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 = array_create_enumerator(this->child_sas);
	while (enumerator->enumerate(enumerator, &child_sa))
	{
		child_sa->get_usestats(child_sa, inbound, &current, NULL, NULL);
		use_time = max(use_time, current);
	}
	enumerator->destroy(enumerator);

	return use_time;
}

METHOD(ike_sa_t, get_unique_id, uint32_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, uint32_t,
	private_ike_sa_t *this, statistic_t kind)
{
	if (kind < STAT_MAX)
	{
		return this->stats[kind];
	}
	return 0;
}

METHOD(ike_sa_t, set_statistic, void,
	private_ike_sa_t *this, statistic_t kind, uint32_t value)
{
	if (kind < STAT_MAX)
	{
		this->stats[kind] = value;
	}
}

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_redirected_from, host_t*,
	private_ike_sa_t *this)
{
	return this->redirected_from;
}

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)
{
	peer_cfg->get_ref(peer_cfg);
	DESTROY_IF(this->peer_cfg);
	this->peer_cfg = peer_cfg;

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

	this->if_id_in = peer_cfg->get_if_id(peer_cfg, TRUE);
	this->if_id_out = peer_cfg->get_if_id(peer_cfg, FALSE);
	allocate_unique_if_ids(&this->if_id_in, &this->if_id_out);
}

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)
	{
		array_insert(this->my_auths, ARRAY_TAIL, cfg);
	}
	else
	{
		array_insert(this->other_auths, ARRAY_TAIL, cfg);
	}
}

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

	this->my_auth->purge(this->my_auth, FALSE);
	this->other_auth->purge(this->other_auth, FALSE);

	while (array_remove(this->my_auths, ARRAY_TAIL, &cfg))
	{
		cfg->destroy(cfg);
	}
	while (array_remove(this->other_auths, ARRAY_TAIL, &cfg))
	{
		cfg->destroy(cfg);
	}
}

METHOD(ike_sa_t, verify_peer_certificate, bool,
	private_ike_sa_t *this)
{
	enumerator_t *e1, *e2, *certs;
	auth_cfg_t *cfg, *cfg_done;
	certificate_t *peer, *cert;
	public_key_t *key;
	auth_cfg_t *auth;
	auth_cfg_wrapper_t *wrapper;
	time_t not_before, not_after;
	bool valid = TRUE, found;

	if (this->state != IKE_ESTABLISHED)
	{
		DBG1(DBG_IKE, "unable to verify peer certificate in state %N",
			 ike_sa_state_names, this->state);
		return FALSE;
	}

	if (!this->flush_auth_cfg &&
		lib->settings->get_bool(lib->settings,
								"%s.flush_auth_cfg", FALSE, lib->ns))
	{	/* we can do this check only once if auth configs are flushed */
		DBG1(DBG_IKE, "unable to verify peer certificate as authentication "
			 "information has been flushed");
		return FALSE;
	}
	this->public.set_condition(&this->public, COND_ONLINE_VALIDATION_SUSPENDED,
							   FALSE);

	e1 = this->peer_cfg->create_auth_cfg_enumerator(this->peer_cfg, FALSE);
	e2 = array_create_enumerator(this->other_auths);
	while (e1->enumerate(e1, &cfg))
	{
		if (!e2->enumerate(e2, &cfg_done))
		{	/* this should not happen as the authentication should never have
			 * succeeded */
			valid = FALSE;
			break;
		}
		if ((uintptr_t)cfg_done->get(cfg_done,
									 AUTH_RULE_AUTH_CLASS) != AUTH_CLASS_PUBKEY)
		{
			continue;
		}
		peer = cfg_done->get(cfg_done, AUTH_RULE_SUBJECT_CERT);
		if (!peer)
		{
			DBG1(DBG_IKE, "no subject certificate found, skipping certificate "
				 "verification");
			continue;
		}
		if (!peer->get_validity(peer, NULL, &not_before, &not_after))
		{
			DBG1(DBG_IKE, "peer certificate invalid (valid from %T to %T)",
				 &not_before, FALSE, &not_after, FALSE);
			valid = FALSE;
			break;
		}
		key = peer->get_public_key(peer);
		if (!key)
		{
			DBG1(DBG_IKE, "unable to retrieve public key, skipping certificate "
				 "verification");
			continue;
		}
		DBG1(DBG_IKE, "verifying peer certificate");
		/* serve received certificates */
		wrapper = auth_cfg_wrapper_create(cfg_done);
		lib->credmgr->add_local_set(lib->credmgr, &wrapper->set, FALSE);
		certs = lib->credmgr->create_trusted_enumerator(lib->credmgr,
							key->get_type(key), peer->get_subject(peer), TRUE);
		key->destroy(key);

		found = FALSE;
		while (certs->enumerate(certs, &cert, &auth))
		{
			if (peer->equals(peer, cert))
			{
				cfg_done->add(cfg_done, AUTH_RULE_CERT_VALIDATION_SUSPENDED,
							  FALSE);
				cfg_done->merge(cfg_done, auth, FALSE);
				valid = cfg_done->complies(cfg_done, cfg, TRUE);
				found = TRUE;
				break;
			}
		}
		certs->destroy(certs);
		lib->credmgr->remove_local_set(lib->credmgr, &wrapper->set);
		wrapper->destroy(wrapper);
		if (!found || !valid)
		{
			valid = FALSE;
			break;
		}
	}
	e1->destroy(e1);
	e2->destroy(e2);

	if (this->flush_auth_cfg)
	{
		this->flush_auth_cfg = FALSE;
		flush_auth_cfgs(this);
	}
	return valid;
}

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, 0);
}

METHOD(ike_sa_t, set_message_id, void,
	private_ike_sa_t *this, bool initiate, uint32_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, get_message_id, uint32_t,
	private_ike_sa_t *this, bool initiate)
{
	return this->task_manager->get_mid(this->task_manager, initiate);
}

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

	if (scheduled)
	{
		this->keepalive_job = NULL;
	}
	if (!this->keepalive_interval || this->state == IKE_PASSIVE)
	{	/* keepalives disabled either by configuration or for passive IKE_SAs */
		return;
	}
	if (!(this->conditions & COND_NAT_HERE) || (this->conditions & COND_STALE))
	{	/* disable keepalives if we are not NATed anymore, or the SA is stale */
		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 to %#H", this->other_host);
		charon->sender->send_no_marker(charon->sender, packet);
		diff = 0;
	}
	if (!this->keepalive_job)
	{
		this->keepalive_job = send_keepalive_job_create(this->ike_sa_id);
		lib->scheduler->schedule_job(lib->scheduler, (job_t*)this->keepalive_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)
{
	DESTROY_IF(this->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, FALSE);
					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_THERE:
					DBG1(DBG_IKE, "%s host is not behind NAT anymore",
						 condition == COND_NAT_HERE ? "local" : "remote");
					/* fall-through */
				case COND_NAT_FAKE:
					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;
				case COND_STALE:
					send_keepalive(this, FALSE);
					break;
				default:
					break;
			}
		}
	}
}

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

	if (this->state == IKE_PASSIVE)
	{
		return INVALID_STATE;
	}
	if (this->version == IKEV1 && this->state == IKE_REKEYING)
	{	/* don't send DPDs for rekeyed IKEv1 SAs */
		return SUCCESS;
	}
	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)
		{
			/* too long ago, initiate dead peer detection */
			DBG1(DBG_IKE, "sending DPD request");
			this->task_manager->queue_dpd(this->task_manager);
			task_queued = TRUE;
			diff = 0;
		}
	}
	/* 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);
	}
	if (task_queued)
	{
		return this->task_manager->initiate(this->task_manager);
	}
	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)
{
	bool trigger_dpd = FALSE, keepalives = FALSE;

	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;
				uint32_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, TRUE);
				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, TRUE);
				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);
				}
				trigger_dpd = this->peer_cfg->get_dpd(this->peer_cfg);
				if (trigger_dpd)
				{
					/* Some peers delay the DELETE after rekeying an IKE_SA.
					 * If this delay is longer than our DPD delay, we would
					 * send a DPD request here. The IKE_SA is not ready to do
					 * so yet, so prevent that. */
					this->stats[STAT_INBOUND] = this->stats[STAT_ESTABLISHED];
				}
				if (this->state == IKE_PASSIVE)
				{
					keepalives = TRUE;
				}
				DESTROY_IF(this->redirected_from);
				this->redirected_from = NULL;
			}
			break;
		}
		default:
			break;
	}
	charon->bus->ike_state_change(charon->bus, &this->public, state);
	this->state = state;

	if (trigger_dpd)
	{
		if (supports_extension(this, EXT_DPD))
		{
			send_dpd(this);
		}
		else
		{
			DBG1(DBG_IKE, "DPD not supported by peer, disabled");
		}
	}
	if (keepalives)
	{
		send_keepalive(this, FALSE);
	}
}

METHOD(ike_sa_t, reset, void,
	private_ike_sa_t *this, bool new_spi)
{
	/* reset the initiator SPI if requested */
	if (new_spi)
	{
		charon->ike_sa_manager->new_initiator_spi(charon->ike_sa_manager,
												  &this->public);

		/* when starting from scratch, connect to the original peer again e.g.
		 * if we got redirected but weren't able to connect successfully */
		if (this->redirected_from)
		{
			this->redirected_from->destroy(this->redirected_from);
			this->redirected_from = NULL;
			/* we can't restore the original value, if there was any */
			DESTROY_IF(this->remote_host);
			this->remote_host = NULL;
		}
	}
	/* 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->version,
							this->ike_sa_id->is_initiator(this->ike_sa_id));

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

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

METHOD(ike_sa_t, add_virtual_ip, void,
	private_ike_sa_t *this, bool local, host_t *ip)
{
	if (local)
	{
		char *iface;

		if (charon->kernel->get_interface(charon->kernel, this->my_host,
										  &iface))
		{
			DBG1(DBG_IKE, "installing new virtual IP %H", ip);
			if (charon->kernel->add_ip(charon->kernel, ip, -1,
									   iface) == SUCCESS)
			{
				array_insert_create(&this->my_vips, ARRAY_TAIL, ip->clone(ip));
			}
			else
			{
				DBG1(DBG_IKE, "installing virtual IP %H failed", ip);
			}
			free(iface);
		}
		else
		{
			DBG1(DBG_IKE, "looking up interface for virtual IP %H failed", ip);
		}
	}
	else
	{
		array_insert_create(&this->other_vips, ARRAY_TAIL, ip->clone(ip));
	}
}


METHOD(ike_sa_t, clear_virtual_ips, void,
	private_ike_sa_t *this, bool local)
{
	array_t *vips;
	host_t *vip;

	vips = local ? this->my_vips : this->other_vips;
	if (!local && array_count(vips))
	{
		charon->bus->assign_vips(charon->bus, &this->public, FALSE);
	}
	while (array_remove(vips, ARRAY_HEAD, &vip))
	{
		if (local)
		{
			charon->kernel->del_ip(charon->kernel, vip, -1, TRUE);
		}
		vip->destroy(vip);
	}
}

METHOD(ike_sa_t, create_virtual_ip_enumerator, enumerator_t*,
	private_ike_sa_t *this, bool local)
{
	if (local)
	{
		return array_create_enumerator(this->my_vips);
	}
	return array_create_enumerator(this->other_vips);
}

METHOD(ike_sa_t, add_peer_address, void,
	private_ike_sa_t *this, host_t *host)
{
	array_insert_create(&this->peer_addresses, ARRAY_TAIL, host);
}

METHOD(ike_sa_t, create_peer_address_enumerator, enumerator_t*,
	private_ike_sa_t *this)
{
	if (this->peer_addresses)
	{
		return array_create_enumerator(this->peer_addresses);
	}
	/* in case we don't have MOBIKE */
	return enumerator_create_single(this->other_host, NULL);
}

METHOD(ike_sa_t, clear_peer_addresses, void,
	private_ike_sa_t *this)
{
	array_destroy_offset(this->peer_addresses, offsetof(host_t, destroy));
	this->peer_addresses = NULL;
}

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, float_ports, void,
	   private_ike_sa_t *this)
{
	/* even if the remote port is not 500 (e.g. because the response was natted)
	 * we switch the remote port if we used port 500 */
	if (this->other_host->get_port(this->other_host) == IKEV2_UDP_PORT ||
		this->my_host->get_port(this->my_host) == IKEV2_UDP_PORT)
	{
		this->other_host->set_port(this->other_host, IKEV2_NATT_PORT);
	}
	if (this->my_host->get_port(this->my_host) ==
			charon->socket->get_port(charon->socket, FALSE))
	{
		this->my_host->set_port(this->my_host,
								charon->socket->get_port(charon->socket, TRUE));
	}
}

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 (force && !me->equals(me, this->my_host))
		{
			charon->bus->ike_update(charon->bus, &this->public, TRUE, me);
			set_my_host(this, me->clone(me));
			update = TRUE;
		}

		if (!other->equals(other, this->other_host) &&
			(force || has_condition(this, COND_NAT_THERE)))
		{
			/* only update other's address if we are behind a static NAT,
			 * which we assume is the case if we are not initiator */
			if (force ||
				(!has_condition(this, COND_NAT_HERE) ||
				 !has_condition(this, COND_ORIGINAL_INITIATOR)))
			{
				charon->bus->ike_update(charon->bus, &this->public, FALSE, other);
				set_other_host(this, other->clone(other));
				update = TRUE;
			}
		}
	}

	/* update all associated CHILD_SAs, if required */
	if (update)
	{
		enumerator_t *enumerator;
		child_sa_t *child_sa;
		linked_list_t *vips;

		vips = linked_list_create_from_enumerator(
									array_create_enumerator(this->my_vips));

		enumerator = array_create_enumerator(this->child_sas);
		while (enumerator->enumerate(enumerator, &child_sa))
		{
			charon->child_sa_manager->remove(charon->child_sa_manager, child_sa);
			charon->child_sa_manager->add(charon->child_sa_manager,
										  child_sa, &this->public);

			if (child_sa->update(child_sa, this->my_host, this->other_host,
					vips, 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));
			}

		}
		enumerator->destroy(enumerator);

		vips->destroy(vips);
	}
}

/**
 * Set configured DSCP value on packet
 */
static void set_dscp(private_ike_sa_t *this, packet_t *packet)
{
	ike_cfg_t *ike_cfg;

	/* prefer IKE config on peer_cfg, as its selection is more accurate
	 * then the initial IKE config */
	if (this->peer_cfg)
	{
		ike_cfg = this->peer_cfg->get_ike_cfg(this->peer_cfg);
	}
	else
	{
		ike_cfg = this->ike_cfg;
	}
	if (ike_cfg)
	{
		packet->set_dscp(packet, ike_cfg->get_dscp(ike_cfg));
	}
}

METHOD(ike_sa_t, generate_message, status_t,
	private_ike_sa_t *this, message_t *message, packet_t **packet)
{
	status_t status;

	if (message->is_encoded(message))
	{	/* already encoded in task, but set DSCP value */
		*packet = message->get_packet(message);
		set_dscp(this, *packet);
		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, TRUE);
	status = message->generate(message, this->keymat, packet);
	if (status == SUCCESS)
	{
		set_dscp(this, *packet);
		charon->bus->message(charon->bus, message, FALSE, FALSE);
	}
	return status;
}

CALLBACK(filter_fragments, bool,
	private_ike_sa_t *this, enumerator_t *orig, va_list args)
{
	packet_t *fragment, **packet;

	VA_ARGS_VGET(args, packet);

	if (orig->enumerate(orig, &fragment))
	{
		*packet = fragment->clone(fragment);
		set_dscp(this, *packet);
		return TRUE;
	}
	return FALSE;
}

METHOD(ike_sa_t, generate_message_fragmented, status_t,
	private_ike_sa_t *this, message_t *message, enumerator_t **packets)
{
	enumerator_t *fragments;
	packet_t *packet;
	status_t status;
	bool use_frags = FALSE;
	bool pre_generated = FALSE;

	if (this->ike_cfg)
	{
		switch (this->ike_cfg->fragmentation(this->ike_cfg))
		{
			case FRAGMENTATION_FORCE:
				use_frags = TRUE;
				break;
			case FRAGMENTATION_YES:
				use_frags = supports_extension(this, EXT_IKE_FRAGMENTATION);
				if (use_frags && this->version == IKEV1 &&
					supports_extension(this, EXT_MS_WINDOWS))
				{
					/* It seems Windows 7 and 8 peers only accept proprietary
					 * fragmented messages if they expect certificates. */
					use_frags = message->get_payload(message,
													 PLV1_CERTIFICATE) != NULL;
				}
				break;
			default:
				break;
		}
	}
	if (!use_frags)
	{
		status = generate_message(this, message, &packet);
		if (status != SUCCESS)
		{
			return status;
		}
		*packets = enumerator_create_single(packet, NULL);
		return SUCCESS;
	}

	pre_generated = message->is_encoded(message);
	this->stats[STAT_OUTBOUND] = time_monotonic(NULL);
	message->set_ike_sa_id(message, this->ike_sa_id);
	if (!pre_generated)
	{
		charon->bus->message(charon->bus, message, FALSE, TRUE);
	}
	status = message->fragment(message, this->keymat, this->fragment_size,
							   &fragments);
	if (status == SUCCESS)
	{
		if (!pre_generated)
		{
			charon->bus->message(charon->bus, message, FALSE, FALSE);
		}
		*packets = enumerator_create_filter(fragments, filter_fragments,
											this, NULL);
	}
	return status;
}

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;
	int family = AF_UNSPEC;

	switch (charon->socket->supported_families(charon->socket))
	{
		case SOCKET_FAMILY_IPV4:
			family = AF_INET;
			break;
		case SOCKET_FAMILY_IPV6:
			family = AF_INET6;
			break;
		case SOCKET_FAMILY_BOTH:
		case SOCKET_FAMILY_NONE:
			break;
	}

	/* if an IP address is set locally, use the same family to resolve remote */
	if (family == AF_UNSPEC && !this->remote_host)
	{
		if (this->local_host)
		{
			family = this->local_host->get_family(this->local_host);
		}
		else
		{
			family = ike_cfg_get_family(this->ike_cfg, TRUE);
		}
	}

	if (this->remote_host)
	{
		host = this->remote_host->clone(this->remote_host);
		host->set_port(host, IKEV2_UDP_PORT);
	}
	else
	{
		host = this->ike_cfg->resolve_other(this->ike_cfg, family);
	}
	if (host)
	{
		if (!host->is_anyaddr(host) ||
			this->other_host->is_anyaddr(this->other_host))
		{	/* don't set to %any if we currently have an address, but the
			 * address family might have changed */
			set_other_host(this, host);
		}
		else
		{	/* reuse the original port as some implementations might not like
			 * initial IKE messages on other ports */
			this->other_host->set_port(this->other_host, host->get_port(host));
			host->destroy(host);
		}
	}

	if (this->local_host)
	{
		host = this->local_host->clone(this->local_host);
		host->set_port(host, charon->socket->get_port(charon->socket, FALSE));
	}
	else
	{
		/* 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 = this->ike_cfg->resolve_me(this->ike_cfg, family);

		if (host && host->is_anyaddr(host) &&
			!this->other_host->is_anyaddr(this->other_host))
		{
			host->destroy(host);
			host = charon->kernel->get_source_addr(charon->kernel,
												   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 = this->ike_cfg->resolve_me(this->ike_cfg, family);
			}
		}
	}
	if (host)
	{
		set_my_host(this, host);
	}
}

METHOD(ike_sa_t, initiate, status_t,
	private_ike_sa_t *this, child_cfg_t *child_cfg, uint32_t reqid,
	traffic_selector_t *tsi, traffic_selector_t *tsr)
{
	bool defer_initiate = FALSE;

	if (this->state == IKE_CREATED)
	{
		if (this->my_host->is_anyaddr(this->my_host) ||
			this->other_host->is_anyaddr(this->other_host))
		{
			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 */
			)
		{
			char *addr;

			addr = this->ike_cfg->get_other_addr(this->ike_cfg);
			if (!this->retry_initiate_interval)
			{
				DBG1(DBG_IKE, "unable to resolve %s, initiate aborted",
					 addr);
				DESTROY_IF(child_cfg);
				charon->bus->alert(charon->bus, ALERT_PEER_ADDR_FAILED);
				return DESTROY_ME;
			}
			DBG1(DBG_IKE, "unable to resolve %s, retrying in %ds",
				 addr, this->retry_initiate_interval);
			defer_initiate = TRUE;
		}

		set_condition(this, COND_ORIGINAL_INITIATOR, TRUE);
		this->task_manager->queue_ike(this->task_manager);
	}

#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 */
	if (child_cfg)
	{
		/* normal IKE_SA with CHILD_SA */
		this->task_manager->queue_child(this->task_manager, child_cfg, reqid,
										tsi, tsr);
#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 */
	}

	if (defer_initiate)
	{
		if (!this->retry_initiate_queued)
		{
			job_t *job = (job_t*)retry_initiate_job_create(this->ike_sa_id);
			lib->scheduler->schedule_job(lib->scheduler, (job_t*)job,
										 this->retry_initiate_interval);
			this->retry_initiate_queued = TRUE;
		}
		return SUCCESS;
	}
	this->retry_initiate_queued = FALSE;
	return this->task_manager->initiate(this->task_manager);
}

METHOD(ike_sa_t, retry_initiate, status_t,
	private_ike_sa_t *this)
{
	if (this->retry_initiate_queued)
	{
		this->retry_initiate_queued = FALSE;
		return initiate(this, NULL, 0, NULL, NULL);
	}
	return SUCCESS;
}

METHOD(ike_sa_t, process_message, status_t,
	private_ike_sa_t *this, message_t *message)
{
	status_t status;

	if (this->state == IKE_PASSIVE)
	{	/* do not handle messages in passive state */
		return FAILED;
	}
	if (message->get_major_version(message) != this->version)
	{
		DBG1(DBG_IKE, "ignoring %N IKEv%u exchange on %N SA",
			 exchange_type_names, message->get_exchange_type(message),
			 message->get_major_version(message),
			 ike_version_names, this->version);
		/* TODO-IKEv1: fall back to IKEv1 if we receive an IKEv1
		 * INVALID_MAJOR_VERSION on an IKEv2 SA. */
		return FAILED;
	}
	status = this->task_manager->process_message(this->task_manager, message);
	if (this->flush_auth_cfg && this->state == IKE_ESTABLISHED)
	{
		/* authentication completed but if the online validation is suspended we
		 * need the auth cfgs until we did the delayed verification, we flush
		 * them afterwards */
		if (!has_condition(this, COND_ONLINE_VALIDATION_SUSPENDED))
		{
			this->flush_auth_cfg = FALSE;
			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_version, ike_version_t,
	private_ike_sa_t *this)
{
	return this->version;
}

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 = array_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_XAUTH_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, get_if_id, uint32_t,
	private_ike_sa_t *this, bool inbound)
{
	return inbound ? this->if_id_in : this->if_id_out;
}

METHOD(ike_sa_t, add_child_sa, void,
	private_ike_sa_t *this, child_sa_t *child_sa)
{
	array_insert_create(&this->child_sas, ARRAY_TAIL, child_sa);
	charon->child_sa_manager->add(charon->child_sa_manager,
								  child_sa, &this->public);
}

METHOD(ike_sa_t, get_child_sa, child_sa_t*,
	private_ike_sa_t *this, protocol_id_t protocol, uint32_t spi, bool inbound)
{
	enumerator_t *enumerator;
	child_sa_t *current, *found = NULL;

	enumerator = array_create_enumerator(this->child_sas);
	while (enumerator->enumerate(enumerator, (void**)&current))
	{
		if (current->get_spi(current, inbound) == spi &&
			current->get_protocol(current) == protocol)
		{
			found = current;
		}
	}
	enumerator->destroy(enumerator);
	return found;
}

METHOD(ike_sa_t, get_child_count, int,
	private_ike_sa_t *this)
{
	return array_count(this->child_sas);
}

/**
 * Private data of a create_child_sa_enumerator()
 */
typedef struct {
	/** implements enumerator */
	enumerator_t public;
	/** inner array enumerator */
	enumerator_t *inner;
	/** current item */
	child_sa_t *current;
} child_enumerator_t;

METHOD(enumerator_t, child_enumerate, bool,
	child_enumerator_t *this, va_list args)
{
	child_sa_t **child_sa;

	VA_ARGS_VGET(args, child_sa);
	if (this->inner->enumerate(this->inner, &this->current))
	{
		*child_sa = this->current;
		return TRUE;
	}
	return FALSE;
}

METHOD(enumerator_t, child_enumerator_destroy, void,
	child_enumerator_t *this)
{
	this->inner->destroy(this->inner);
	free(this);
}

METHOD(ike_sa_t, create_child_sa_enumerator, enumerator_t*,
	private_ike_sa_t *this)
{
	child_enumerator_t *enumerator;

	INIT(enumerator,
		.public = {
			.enumerate = enumerator_enumerate_default,
			.venumerate = _child_enumerate,
			.destroy = _child_enumerator_destroy,
		},
		.inner = array_create_enumerator(this->child_sas),
	);
	return &enumerator->public;
}

METHOD(ike_sa_t, remove_child_sa, void,
	private_ike_sa_t *this, enumerator_t *enumerator)
{
	child_enumerator_t *ce = (child_enumerator_t*)enumerator;

	charon->child_sa_manager->remove(charon->child_sa_manager, ce->current);
	array_remove_at(this->child_sas, ce->inner);
}

METHOD(ike_sa_t, rekey_child_sa, status_t,
	private_ike_sa_t *this, protocol_id_t protocol, uint32_t spi)
{
	if (this->state == IKE_PASSIVE)
	{
		return INVALID_STATE;
	}
	this->task_manager->queue_child_rekey(this->task_manager, protocol, spi);
	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, uint32_t spi, bool expired)
{
	if (this->state == IKE_PASSIVE)
	{
		return INVALID_STATE;
	}
	this->task_manager->queue_child_delete(this->task_manager,
										   protocol, spi, expired);
	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, uint32_t spi)
{
	enumerator_t *enumerator;
	child_sa_t *child_sa;
	status_t status = NOT_FOUND;

	enumerator = create_child_sa_enumerator(this);
	while (enumerator->enumerate(enumerator, (void**)&child_sa))
	{
		if (child_sa->get_protocol(child_sa) == protocol &&
			child_sa->get_spi(child_sa, TRUE) == spi)
		{
			remove_child_sa(this, enumerator);
			child_sa->destroy(child_sa);
			status = SUCCESS;
			break;
		}
	}
	enumerator->destroy(enumerator);
	return status;
}

METHOD(ike_sa_t, delete_, status_t,
	private_ike_sa_t *this, bool force)
{
	status_t status = DESTROY_ME;

	switch (this->state)
	{
		case IKE_ESTABLISHED:
		case IKE_REKEYING:
			if (time_monotonic(NULL) >= this->stats[STAT_DELETE] &&
				!(this->version == IKEV1 && this->state == IKE_REKEYING))
			{	/* IKE_SA hard lifetime hit, ignored for reauthenticated
				 * IKEv1 SAs */
				charon->bus->alert(charon->bus, ALERT_IKE_SA_EXPIRED);
			}
			this->task_manager->queue_ike_delete(this->task_manager);
			status = this->task_manager->initiate(this->task_manager);
			break;
		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);
			force = TRUE;
			break;
	}

	if (force)
	{
		status = DESTROY_ME;

		if (this->version == IKEV2)
		{	/* for IKEv1 we trigger this in the ISAKMP delete task */
			switch (this->state)
			{
				case IKE_ESTABLISHED:
				case IKE_REKEYING:
				case IKE_DELETING:
					charon->bus->ike_updown(charon->bus, &this->public, FALSE);
				default:
					break;
			}
		}
	}
	return status;
}

METHOD(ike_sa_t, rekey, status_t,
	private_ike_sa_t *this)
{
	if (this->state == IKE_PASSIVE)
	{
		return INVALID_STATE;
	}
	this->task_manager->queue_ike_rekey(this->task_manager);
	return this->task_manager->initiate(this->task_manager);
}

METHOD(ike_sa_t, reauth, status_t,
	private_ike_sa_t *this)
{
	if (this->state == IKE_PASSIVE)
	{
		return INVALID_STATE;
	}
	if (this->state == IKE_CONNECTING)
	{
		DBG0(DBG_IKE, "reinitiating IKE_SA %s[%d]",
			 get_name(this), this->unique_id);
		reset(this, TRUE);
		return this->task_manager->initiate(this->task_manager);
	}
	/* 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 (array_count(this->other_vips) != 0 ||
			has_condition(this, COND_XAUTH_AUTHENTICATED) ||
			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 del, now;

			del = this->stats[STAT_DELETE];
			now = time_monotonic(NULL);
			DBG1(DBG_IKE, "IKE_SA %s[%d] will timeout in %V",
				 get_name(this), this->unique_id, &now, &del);
			return FAILED;
		}
		else
		{
			DBG0(DBG_IKE, "reauthenticating IKE_SA %s[%d] actively",
				 get_name(this), this->unique_id);
		}
	}
	else
	{
		DBG0(DBG_IKE, "reauthenticating IKE_SA %s[%d]",
			 get_name(this), this->unique_id);
	}
	set_condition(this, COND_REAUTHENTICATING, TRUE);
	this->task_manager->queue_ike_reauth(this->task_manager);
	return this->task_manager->initiate(this->task_manager);
}

/**
 * Check if any tasks of a specific type are queued in the given queue.
 */
static bool is_task_queued(private_ike_sa_t *this, task_queue_t queue,
						   task_type_t type)
{
	enumerator_t *enumerator;
	task_t *task;
	bool found = FALSE;

	enumerator = this->task_manager->create_task_enumerator(this->task_manager,
															queue);
	while (enumerator->enumerate(enumerator, &task))
	{
		if (task->get_type(task) == type)
		{
			found = TRUE;
			break;
		}
	}
	enumerator->destroy(enumerator);
	return found;
}

/**
 * Check if any tasks to create CHILD_SAs are queued in the given queue.
 */
static bool is_child_queued(private_ike_sa_t *this, task_queue_t queue)
{
	return is_task_queued(this, queue,
				this->version == IKEV1 ? TASK_QUICK_MODE : TASK_CHILD_CREATE);
}

/**
 * Check if any tasks to delete the IKE_SA are queued in the given queue.
 */
static bool is_delete_queued(private_ike_sa_t *this, task_queue_t queue)
{
	return is_task_queued(this, queue,
				this->version == IKEV1 ? TASK_ISAKMP_DELETE : TASK_IKE_DELETE);
}

/**
 * Reestablish CHILD_SAs and migrate queued tasks.
 *
 * If force is true all SAs are restarted, otherwise their close/dpd_action
 * is followed.
 */
static status_t reestablish_children(private_ike_sa_t *this, ike_sa_t *new,
									 bool force)
{
	enumerator_t *enumerator;
	child_sa_t *child_sa;
	child_cfg_t *child_cfg;
	action_t action;
	status_t status = FAILED;

	/* handle existing CHILD_SAs */
	enumerator = create_child_sa_enumerator(this);
	while (enumerator->enumerate(enumerator, (void**)&child_sa))
	{
		switch (child_sa->get_state(child_sa))
		{
			case CHILD_REKEYED:
			case CHILD_DELETED:
				/* ignore CHILD_SAs in these states */
				continue;
			default:
				break;
		}
		if (force)
		{
			action = ACTION_RESTART;
		}
		else
		{	/* only restart CHILD_SAs that are configured accordingly */
			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,
								child_sa->get_reqid(child_sa), NULL, NULL);
				break;
			default:
				continue;
		}
		if (status == DESTROY_ME)
		{
			break;
		}
	}
	enumerator->destroy(enumerator);
	/* adopt any active or queued CHILD-creating tasks */
	if (status != DESTROY_ME)
	{
		new->adopt_child_tasks(new, &this->public);
		if (new->get_state(new) == IKE_CREATED)
		{
			status = new->initiate(new, NULL, 0, NULL, NULL);
		}
	}
	return status;
}

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

	if (is_delete_queued(this, TASK_QUEUE_QUEUED))
	{	/* don't reestablish IKE_SAs that have explicitly been deleted in the
		 * mean time */
		return FAILED;
	}

	if (has_condition(this, COND_REAUTHENTICATING))
	{	/* only reauthenticate if we have children */
		if (array_count(this->child_sas) == 0
#ifdef ME
			/* allow reauth of mediation connections without CHILD_SAs */
			&& !this->peer_cfg->is_mediation(this->peer_cfg)
#endif /* ME */
			)
		{
			DBG1(DBG_IKE, "unable to reauthenticate IKE_SA, no CHILD_SA "
				 "to recreate");
		}
		else
		{
			restart = TRUE;
		}
	}
	else
	{	/* check if we have children to keep up at all */
		enumerator = array_create_enumerator(this->child_sas);
		while (enumerator->enumerate(enumerator, (void**)&child_sa))
		{
			switch (child_sa->get_state(child_sa))
			{
				case CHILD_REKEYED:
				case CHILD_DELETED:
					/* ignore CHILD_SAs in these states */
					continue;
				default:
					break;
			}
			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;
			}
		}
		enumerator->destroy(enumerator);
		/* check if we have tasks that recreate children */
		if (!restart)
		{
			restart = is_child_queued(this, TASK_QUEUE_ACTIVE) ||
					  is_child_queued(this, TASK_QUEUE_QUEUED);
		}
#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) &&
		(array_count(this->other_vips) != 0 ||
		 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,
											   this->version, TRUE);
	if (!new)
	{
		return FAILED;
	}
	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));
	charon->bus->ike_reestablish_pre(charon->bus, &this->public, new);
	if (!has_condition(this, COND_REAUTHENTICATING))
	{	/* reauthenticate to the same addresses, but resolve hosts if
		 * reestablishing (old addresses serve as fallback) */
		resolve_hosts((private_ike_sa_t*)new);
	}
	/* if we already have a virtual IP, we reuse it */
	enumerator = array_create_enumerator(this->my_vips);
	while (enumerator->enumerate(enumerator, &host))
	{
		new->add_virtual_ip(new, TRUE, host);
	}
	enumerator->destroy(enumerator);

#ifdef ME
	if (this->peer_cfg->is_mediation(this->peer_cfg))
	{
		status = new->initiate(new, NULL, 0, NULL, NULL);
	}
	else
#endif /* ME */
	{
		status = reestablish_children(this, new,
									has_condition(this, COND_REAUTHENTICATING));
	}

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

/**
 * Resolve the given gateway ID
 */
static host_t *resolve_gateway_id(identification_t *gateway)
{
	char gw[BUF_LEN];
	host_t *addr;

	snprintf(gw, sizeof(gw), "%Y", gateway);
	gw[sizeof(gw)-1] = '\0';
	addr = host_create_from_dns(gw, AF_UNSPEC, IKEV2_UDP_PORT);
	if (!addr)
	{
		DBG1(DBG_IKE, "unable to resolve gateway ID '%Y', redirect failed",
			 gateway);
	}
	return addr;
}

/**
 * Redirect the current SA to the given target host
 */
static bool redirect_established(private_ike_sa_t *this, identification_t *to)
{
	private_ike_sa_t *new_priv;
	ike_sa_t *new;
	host_t *other;
	time_t redirect;

	new = charon->ike_sa_manager->checkout_new(charon->ike_sa_manager,
											   this->version, TRUE);
	if (!new)
	{
		return FALSE;
	}
	new_priv = (private_ike_sa_t*)new;
	new->set_peer_cfg(new, this->peer_cfg);
	new_priv->redirected_from = this->other_host->clone(this->other_host);
	charon->bus->ike_reestablish_pre(charon->bus, &this->public, new);
	other = resolve_gateway_id(to);
	if (other)
	{
		set_my_host(new_priv, this->my_host->clone(this->my_host));
		/* this allows us to force the remote address while we still properly
		 * resolve the local address */
		new_priv->remote_host = other;
		resolve_hosts(new_priv);
		new_priv->redirected_at = array_create(sizeof(time_t), MAX_REDIRECTS);
		while (array_remove(this->redirected_at, ARRAY_HEAD, &redirect))
		{
			array_insert(new_priv->redirected_at, ARRAY_TAIL, &redirect);
		}
		if (reestablish_children(this, new, TRUE) != DESTROY_ME)
		{
#ifdef USE_IKEV2
			new->queue_task(new, (task_t*)ike_reauth_complete_create(new,
															 this->ike_sa_id));
#endif
			charon->bus->ike_reestablish_post(charon->bus, &this->public, new,
											  TRUE);
			charon->ike_sa_manager->checkin(charon->ike_sa_manager, new);
			charon->bus->set_sa(charon->bus, &this->public);
			return TRUE;
		}
	}
	charon->bus->ike_reestablish_post(charon->bus, &this->public, new,
									  FALSE);
	charon->ike_sa_manager->checkin_and_destroy(charon->ike_sa_manager, new);
	charon->bus->set_sa(charon->bus, &this->public);
	return FALSE;
}

/**
 * Redirect the current connecting SA to the given target host
 */
static bool redirect_connecting(private_ike_sa_t *this, identification_t *to)
{
	host_t *other;

	other = resolve_gateway_id(to);
	if (!other)
	{
		return FALSE;
	}
	reset(this, TRUE);
	DESTROY_IF(this->redirected_from);
	this->redirected_from = this->other_host->clone(this->other_host);
	/* this allows us to force the remote address while we still properly
	 * resolve the local address */
	DESTROY_IF(this->remote_host);
	this->remote_host = other;
	resolve_hosts(this);
	return TRUE;
}

/**
 * Check if the current redirect exceeds the limits for redirects
 */
static bool redirect_count_exceeded(private_ike_sa_t *this)
{
	time_t now, redirect;

	now = time_monotonic(NULL);
	/* remove entries outside the defined period */
	while (array_get(this->redirected_at, ARRAY_HEAD, &redirect) &&
		   now - redirect >= REDIRECT_LOOP_DETECT_PERIOD)
	{
		array_remove(this->redirected_at, ARRAY_HEAD, NULL);
	}
	if (array_count(this->redirected_at) < MAX_REDIRECTS)
	{
		if (!this->redirected_at)
		{
			this->redirected_at = array_create(sizeof(time_t), MAX_REDIRECTS);
		}
		array_insert(this->redirected_at, ARRAY_TAIL, &now);
		return FALSE;
	}
	return TRUE;
}

METHOD(ike_sa_t, handle_redirect, bool,
	private_ike_sa_t *this, identification_t *gateway)
{
	DBG1(DBG_IKE, "redirected to %Y", gateway);
	if (!this->follow_redirects)
	{
		DBG1(DBG_IKE, "server sent REDIRECT even though we disabled it");
		return FALSE;
	}
	if (redirect_count_exceeded(this))
	{
		DBG1(DBG_IKE, "only %d redirects are allowed within %d seconds",
			 MAX_REDIRECTS, REDIRECT_LOOP_DETECT_PERIOD);
		return FALSE;
	}

	switch (this->state)
	{
		case IKE_CONNECTING:
			return redirect_connecting(this, gateway);
		case IKE_ESTABLISHED:
			return redirect_established(this, gateway);
		default:
			DBG1(DBG_IKE, "unable to handle redirect for IKE_SA in state %N",
				 ike_sa_state_names, this->state);
			return FALSE;
	}
}

METHOD(ike_sa_t, redirect, status_t,
	private_ike_sa_t *this, identification_t *gateway)
{
	switch (this->state)
	{
		case IKE_CONNECTING:
		case IKE_ESTABLISHED:
		case IKE_REKEYING:
			if (has_condition(this, COND_REDIRECTED))
			{	/* IKE_SA already got redirected */
				return SUCCESS;
			}
			if (has_condition(this, COND_ORIGINAL_INITIATOR))
			{
				DBG1(DBG_IKE, "unable to redirect IKE_SA as initiator");
				return FAILED;
			}
			if (this->version == IKEV1)
			{
				DBG1(DBG_IKE, "unable to redirect IKEv1 SA");
				return FAILED;
			}
			if (!supports_extension(this, EXT_IKE_REDIRECTION))
			{
				DBG1(DBG_IKE, "client does not support IKE redirection");
				return FAILED;
			}
#ifdef USE_IKEV2
			this->task_manager->queue_task(this->task_manager,
						(task_t*)ike_redirect_create(&this->public, gateway));
#endif
			return this->task_manager->initiate(this->task_manager);
		default:
			DBG1(DBG_IKE, "unable to redirect IKE_SA in state %N",
				 ike_sa_state_names, this->state);
			return INVALID_STATE;
	}
}

METHOD(ike_sa_t, retransmit, status_t,
	private_ike_sa_t *this, uint32_t message_id)
{
	if (this->state == IKE_PASSIVE)
	{
		return INVALID_STATE;
	}
	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/Main Mode if we have multiple keyingtries */
				uint32_t tries = this->peer_cfg->get_keyingtries(this->peer_cfg);
				charon->bus->alert(charon->bus, ALERT_PEER_INIT_UNREACHABLE,
								   this->keyingtry);
				this->keyingtry++;
				if (tries == 0 || tries > this->keyingtry)
				{
					DBG1(DBG_IKE, "peer not responding, trying again (%d/%d)",
						 this->keyingtry + 1, tries);
					reset(this, TRUE);
					resolve_hosts(this);
					return this->task_manager->initiate(this->task_manager);
				}
				DBG1(DBG_IKE, "establishing IKE_SA failed, peer not responding");

				if (this->version == IKEV1 && array_count(this->child_sas))
				{
					enumerator_t *enumerator;
					child_sa_t *child_sa;

					/* if reauthenticating an IKEv1 SA failed (assumed for an SA
					 * in this state with CHILD_SAs), try again from scratch */
					DBG1(DBG_IKE, "reauthentication failed, trying to "
						 "reestablish IKE_SA");
					reestablish(this);
					/* trigger down events for the CHILD_SAs, as no down event
					 * is triggered below for IKE SAs in this state */
					enumerator = array_create_enumerator(this->child_sas);
					while (enumerator->enumerate(enumerator, &child_sa))
					{
						if (child_sa->get_state(child_sa) != CHILD_REKEYED &&
							child_sa->get_state(child_sa) != CHILD_DELETED)
						{
							charon->bus->child_updown(charon->bus, child_sa,
													  FALSE);
						}
					}
					enumerator->destroy(enumerator);
				}
				break;
			}
			case IKE_DELETING:
				DBG1(DBG_IKE, "proper IKE_SA delete failed, peer not responding");
				if (has_condition(this, COND_REAUTHENTICATING) &&
					!lib->settings->get_bool(lib->settings,
										"%s.make_before_break", FALSE, lib->ns))
				{
					DBG1(DBG_IKE, "delete during reauthentication failed, "
						 "trying to reestablish IKE_SA anyway");
					reestablish(this);
				}
				break;
			case IKE_REKEYING:
				DBG1(DBG_IKE, "rekeying IKE_SA failed, peer not responding");
				/* FALL */
			default:
				reestablish(this);
				break;
		}
		if (this->state != IKE_CONNECTING &&
			this->state != IKE_REKEYED)
		{
			charon->bus->ike_updown(charon->bus, &this->public, FALSE);
		}
		return DESTROY_ME;
	}
	return SUCCESS;
}

METHOD(ike_sa_t, set_auth_lifetime, status_t,
	private_ike_sa_t *this, uint32_t lifetime)
{
	uint32_t diff, hard, soft, now;
	bool send_update;

	diff = this->peer_cfg->get_over_time(this->peer_cfg);
	now = time_monotonic(NULL);
	hard = now + lifetime;
	soft = hard - diff;

	/* check if we have to send an AUTH_LIFETIME to enforce the new lifetime.
	 * We send the notify in IKE_AUTH if not yet ESTABLISHED. */
	send_update = this->state == IKE_ESTABLISHED && this->version == IKEV2 &&
				  !has_condition(this, COND_ORIGINAL_INITIATOR) &&
				  (array_count(this->other_vips) != 0 ||
				  has_condition(this, COND_EAP_AUTHENTICATED));

	if (lifetime < diff)
	{
		this->stats[STAT_REAUTH] = now;

		if (!send_update)
		{
			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] > soft)
	{
		this->stats[STAT_REAUTH] = soft;
		if (!send_update)
		{
			DBG1(DBG_IKE, "received AUTH_LIFETIME of %ds, scheduling "
				 "reauthentication in %ds", lifetime, lifetime - diff);
			lib->scheduler->schedule_job(lib->scheduler,
						(job_t*)rekey_ike_sa_job_create(this->ike_sa_id, TRUE),
						lifetime - diff);
		}
	}
	else
	{
		DBG1(DBG_IKE, "received AUTH_LIFETIME of %ds, "
			 "reauthentication already scheduled in %ds", lifetime,
			 this->stats[STAT_REAUTH] - time_monotonic(NULL));
		send_update = FALSE;
	}
	/* give at least some seconds to reauthenticate */
	this->stats[STAT_DELETE] = max(hard, now + 10);

#ifdef USE_IKEV2
	if (send_update)
	{
		ike_auth_lifetime_t *task;

		task = ike_auth_lifetime_create(&this->public, TRUE);
		this->task_manager->queue_task(this->task_manager, &task->task);
		return this->task_manager->initiate(this->task_manager);
	}
#endif
	return SUCCESS;
}

/**
 * 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;

	if (supports_extension(this, EXT_MOBIKE) &&
		lib->settings->get_bool(lib->settings,
								"%s.prefer_best_path", FALSE, lib->ns))
	{
		/* check if the current path is the best path; migrate otherwise */
		src = charon->kernel->get_source_addr(charon->kernel, this->other_host,
											  NULL);
		if (src)
		{
			valid = src->ip_equals(src, this->my_host);
			src->destroy(src);
		}
		if (!valid)
		{
			DBG1(DBG_IKE, "old path is not preferred anymore");
		}
		return valid;
	}
	src = charon->kernel->get_source_addr(charon->kernel, this->other_host,
										  this->my_host);
	if (src)
	{
		if (src->ip_equals(src, this->my_host))
		{
			valid = TRUE;
		}
		src->destroy(src);
	}
	if (!valid)
	{
		DBG1(DBG_IKE, "old path is not available anymore, try to find another");
	}
	return valid;
}

/**
 * Check if we have any path available for this IKE SA.
 */
static bool is_any_path_valid(private_ike_sa_t *this)
{
	bool valid = FALSE;
	enumerator_t *enumerator;
	host_t *src = NULL, *addr;
	int family = AF_UNSPEC;

	switch (charon->socket->supported_families(charon->socket))
	{
		case SOCKET_FAMILY_IPV4:
			family = AF_INET;
			break;
		case SOCKET_FAMILY_IPV6:
			family = AF_INET6;
			break;
		case SOCKET_FAMILY_BOTH:
		case SOCKET_FAMILY_NONE:
			break;
	}

	enumerator = create_peer_address_enumerator(this);
	while (enumerator->enumerate(enumerator, &addr))
	{
		if (family != AF_UNSPEC && addr->get_family(addr) != family)
		{
			continue;
		}
		DBG1(DBG_IKE, "looking for a route to %H ...", addr);
		src = charon->kernel->get_source_addr(charon->kernel, 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)
{
	switch (this->state)
	{
		case IKE_CREATED:
		case IKE_DELETING:
		case IKE_DESTROYING:
		case IKE_PASSIVE:
		case IKE_REKEYED:
			return SUCCESS;
		default:
			break;
	}

	if (!this->ike_cfg)
	{	/* this is the case for new HA SAs not yet in state IKE_PASSIVE and
		 * without config assigned */
		return SUCCESS;
	}
	if (this->version == IKEV1)
	{	/* ignore roam events for IKEv1 where we don't have MOBIKE and would
		 * have to reestablish from scratch (reauth is not enough) */
		return SUCCESS;
	}

	/* ignore roam events if MOBIKE is not supported/enabled and the local
	 * address is statically configured */
	if (!supports_extension(this, EXT_MOBIKE) &&
		ike_cfg_has_address(this->ike_cfg, this->my_host, TRUE))
	{
		DBG2(DBG_IKE, "keeping statically configured path %H - %H",
			 this->my_host, this->other_host);
		return SUCCESS;
	}

	/* 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");
			this->task_manager->queue_mobike(this->task_manager, FALSE, TRUE);
			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");
		}
		this->task_manager->queue_mobike(this->task_manager, TRUE, address);
		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");
	/* since our previous path is not valid anymore, try and find a new one */
	resolve_hosts(this);
	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 = {
		.handler = handler,
		.type = type,
		.data = chunk_clone(data),
	};
	array_insert(this->attributes, ARRAY_TAIL, &entry);
}

CALLBACK(filter_attribute, bool,
	void *null, enumerator_t *orig, va_list args)
{
	attribute_entry_t *entry;
	configuration_attribute_type_t *type;
	chunk_t *data;
	bool *handled;

	VA_ARGS_VGET(args, type, data, handled);

	if (orig->enumerate(orig, &entry))
	{
		*type = entry->type;
		*data = entry->data;
		*handled = entry->handler != NULL;
		return TRUE;
	}
	return FALSE;
}

METHOD(ike_sa_t, create_attribute_enumerator, enumerator_t*,
	private_ike_sa_t *this)
{
	return enumerator_create_filter(array_create_enumerator(this->attributes),
									filter_attribute, NULL, NULL);
}

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, remove_task, void,
	private_ike_sa_t *this, enumerator_t *enumerator)
{
	return this->task_manager->remove_task(this->task_manager, enumerator);
}

METHOD(ike_sa_t, flush_queue, void,
	private_ike_sa_t *this, task_queue_t queue)
{
	this->task_manager->flush_queue(this->task_manager, queue);
}

METHOD(ike_sa_t, queue_task, void,
	private_ike_sa_t *this, task_t *task)
{
	this->task_manager->queue_task(this->task_manager, task);
}

METHOD(ike_sa_t, queue_task_delayed, void,
	private_ike_sa_t *this, task_t *task, uint32_t delay)
{
	this->task_manager->queue_task_delayed(this->task_manager, task, delay);
}

/**
 * Migrate and queue child-creating tasks from another IKE_SA
 */
static void migrate_child_tasks(private_ike_sa_t *this, ike_sa_t *other,
								task_queue_t queue)
{
	enumerator_t *enumerator;
	task_t *task;

	enumerator = other->create_task_enumerator(other, queue);
	while (enumerator->enumerate(enumerator, &task))
	{
		if (task->get_type(task) == TASK_CHILD_CREATE ||
			task->get_type(task) == TASK_QUICK_MODE)
		{
			other->remove_task(other, enumerator);
			task->migrate(task, &this->public);
			queue_task(this, task);
		}
	}
	enumerator->destroy(enumerator);
}

METHOD(ike_sa_t, adopt_child_tasks, void,
	private_ike_sa_t *this, ike_sa_t *other)
{
	migrate_child_tasks(this, other, TASK_QUEUE_ACTIVE);
	migrate_child_tasks(this, other, TASK_QUEUE_QUEUED);
}

METHOD(ike_sa_t, inherit_pre, void,
	private_ike_sa_t *this, ike_sa_t *other_public)
{
	private_ike_sa_t *other = (private_ike_sa_t*)other_public;

	/* apply config and hosts */
	set_peer_cfg(this, other->peer_cfg);
	set_my_host(this, other->my_host->clone(other->my_host));
	set_other_host(this, other->other_host->clone(other->other_host));

	/* apply extensions and conditions with a few exceptions */
	this->extensions = other->extensions;
	this->conditions = other->conditions;
	this->conditions &= ~COND_STALE;
	this->conditions &= ~COND_REAUTHENTICATING;
}

METHOD(ike_sa_t, inherit_post, 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;
	enumerator_t *enumerator;
	attribute_entry_t entry;
	auth_cfg_t *cfg;
	host_t *vip;

	/* 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);
	this->if_id_in = other->if_id_in;
	this->if_id_out = other->if_id_out;

	/* apply assigned virtual IPs... */
	while (array_remove(other->my_vips, ARRAY_HEAD, &vip))
	{
		array_insert_create(&this->my_vips, ARRAY_TAIL, vip);
	}
	while (array_remove(other->other_vips, ARRAY_HEAD, &vip))
	{
		array_insert_create(&this->other_vips, ARRAY_TAIL, vip);
	}

	/* MOBIKE additional addresses */
	while (array_remove(other->peer_addresses, ARRAY_HEAD, &vip))
	{
		array_insert_create(&this->peer_addresses, ARRAY_TAIL, vip);
	}

	/* authentication information */
	enumerator = array_create_enumerator(other->my_auths);
	while (enumerator->enumerate(enumerator, &cfg))
	{
		array_insert(this->my_auths, ARRAY_TAIL, cfg->clone(cfg));
	}
	enumerator->destroy(enumerator);
	enumerator = array_create_enumerator(other->other_auths);
	while (enumerator->enumerate(enumerator, &cfg))
	{
		array_insert(this->other_auths, ARRAY_TAIL, cfg->clone(cfg));
	}
	enumerator->destroy(enumerator);

	/* ... and configuration attributes */
	while (array_remove(other->attributes, ARRAY_HEAD, &entry))
	{
		array_insert(this->attributes, ARRAY_TAIL, &entry);
	}

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

#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 (array_remove(other->child_sas, ARRAY_HEAD, &child_sa))
	{
		charon->child_sa_manager->remove(charon->child_sa_manager, child_sa);
		add_child_sa(this, 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;
	child_sa_t *child_sa;
	host_t *vip;

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

	set_state(this, IKE_DESTROYING);
	if (this->task_manager)
	{
		this->task_manager->flush(this->task_manager);
	}

	/* remove attributes first, as we pass the IKE_SA to the handler */
	charon->bus->handle_vips(charon->bus, &this->public, FALSE);
	while (array_remove(this->attributes, ARRAY_TAIL, &entry))
	{
		if (entry.handler)
		{
			charon->attributes->release(charon->attributes, entry.handler,
										&this->public, entry.type, entry.data);
		}
		free(entry.data.ptr);
	}
	/* uninstall CHILD_SAs before virtual IPs, otherwise we might kill
	 * routes that the CHILD_SA tries to uninstall. */
	while (array_remove(this->child_sas, ARRAY_TAIL, &child_sa))
	{
		charon->child_sa_manager->remove(charon->child_sa_manager, child_sa);
		child_sa->destroy(child_sa);
	}
	while (array_remove(this->my_vips, ARRAY_TAIL, &vip))
	{
		charon->kernel->del_ip(charon->kernel, vip, -1, TRUE);
		vip->destroy(vip);
	}
	if (array_count(this->other_vips))
	{
		charon->bus->assign_vips(charon->bus, &this->public, FALSE);
	}
	while (array_remove(this->other_vips, ARRAY_TAIL, &vip))
	{
		if (this->peer_cfg)
		{
			linked_list_t *pools;

			pools = linked_list_create_from_enumerator(
						this->peer_cfg->create_pool_enumerator(this->peer_cfg));
			charon->attributes->release_address(charon->attributes,
												pools, vip, &this->public);
			pools->destroy(pools);
		}
		vip->destroy(vip);
	}

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

	array_destroy(this->child_sas);
	DESTROY_IF(this->task_manager);
	DESTROY_IF(this->keymat);
	array_destroy(this->attributes);
	array_destroy(this->my_vips);
	array_destroy(this->other_vips);
	array_destroy_offset(this->peer_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->redirected_from);
	array_destroy(this->redirected_at);

	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);
	array_destroy_offset(this->my_auths, offsetof(auth_cfg_t, destroy));
	array_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, bool initiator,
						 ike_version_t version)
{
	private_ike_sa_t *this;
	static refcount_t unique_id = 0;

	if (version == IKE_ANY)
	{	/* prefer IKEv2 if protocol not specified */
#ifdef USE_IKEV2
		version = IKEV2;
#else
		version = IKEV1;
#endif
	}

	INIT(this,
		.public = {
			.get_version = _get_version,
			.get_state = _get_state,
			.set_state = _set_state,
			.get_name = _get_name,
			.get_statistic = _get_statistic,
			.set_statistic = _set_statistic,
			.process_message = _process_message,
			.initiate = _initiate,
			.retry_initiate = _retry_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,
			.verify_peer_certificate = _verify_peer_certificate,
			.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,
			.get_message_id = _get_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,
			.create_peer_address_enumerator = _create_peer_address_enumerator,
			.add_peer_address = _add_peer_address,
			.clear_peer_addresses = _clear_peer_addresses,
			.has_mapping_changed = _has_mapping_changed,
			.retransmit = _retransmit,
			.delete = _delete_,
			.destroy = _destroy,
			.send_dpd = _send_dpd,
			.send_keepalive = _send_keepalive,
			.redirect = _redirect,
			.handle_redirect = _handle_redirect,
			.get_redirected_from = _get_redirected_from,
			.get_keymat = _get_keymat,
			.add_child_sa = _add_child_sa,
			.get_child_sa = _get_child_sa,
			.get_child_count = _get_child_count,
			.create_child_sa_enumerator = _create_child_sa_enumerator,
			.remove_child_sa = _remove_child_sa,
			.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_pre = _inherit_pre,
			.inherit_post = _inherit_post,
			.generate_message = _generate_message,
			.generate_message_fragmented = _generate_message_fragmented,
			.reset = _reset,
			.get_unique_id = _get_unique_id,
			.add_virtual_ip = _add_virtual_ip,
			.clear_virtual_ips = _clear_virtual_ips,
			.create_virtual_ip_enumerator = _create_virtual_ip_enumerator,
			.add_configuration_attribute = _add_configuration_attribute,
			.create_attribute_enumerator = _create_attribute_enumerator,
			.get_if_id = _get_if_id,
			.set_kmaddress = _set_kmaddress,
			.create_task_enumerator = _create_task_enumerator,
			.remove_task = _remove_task,
			.flush_queue = _flush_queue,
			.queue_task = _queue_task,
			.queue_task_delayed = _queue_task_delayed,
			.adopt_child_tasks = _adopt_child_tasks,
#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),
		.version = version,
		.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(version, initiator),
		.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 = array_create(0, 0),
		.other_auths = array_create(0, 0),
		.attributes = array_create(sizeof(attribute_entry_t), 0),
		.unique_id = ref_get(&unique_id),
		.keepalive_interval = lib->settings->get_time(lib->settings,
								"%s.keep_alive", KEEPALIVE_INTERVAL, lib->ns),
		.retry_initiate_interval = lib->settings->get_time(lib->settings,
								"%s.retry_initiate_interval", 0, lib->ns),
		.flush_auth_cfg = lib->settings->get_bool(lib->settings,
								"%s.flush_auth_cfg", FALSE, lib->ns),
		.fragment_size = lib->settings->get_int(lib->settings,
								"%s.fragment_size", 1280, lib->ns),
		.follow_redirects = lib->settings->get_bool(lib->settings,
								"%s.follow_redirects", TRUE, lib->ns),
	);

	if (version == IKEV2)
	{	/* always supported with IKEv2 */
		enable_extension(this, EXT_DPD);
	}

	this->task_manager = task_manager_create(&this->public);
	this->my_host->set_port(this->my_host,
							charon->socket->get_port(charon->socket, FALSE));

	if (!this->task_manager || !this->keymat)
	{
		DBG1(DBG_IKE, "IKE version %d not supported", this->version);
		destroy(this);
		return NULL;
	}
	return &this->public;
}