Support for closing CHILD/IKE_SA if a CHILD_SA is inactive.

NEWS

@@ -12,6 +12,11 @@ strongswan-4.3.6
 
 - The IKEv1 and IKEV2 daemons now check certificate path length constraints.
 
+- The new strongswan.conf option "charon.inactivity_timeout" closes a CHILD_SA
+  if no traffic was sent or received within the given interval. To close the
+  complete IKE_SA if its only CHILD_SA was inactive, set
+  "charon.inactivity_close_ike" to yes.
+
 - More detailed IKEv2 EAP payload information in debug output
 
 - IKEv2 EAP-SIM and EAP-AKA share joint libsimaka library

src/charon/Makefile.am

@@ -60,6 +60,7 @@ processing/jobs/send_dpd_job.c processing/jobs/send_dpd_job.h \
 processing/jobs/send_keepalive_job.c processing/jobs/send_keepalive_job.h \
 processing/jobs/roam_job.c processing/jobs/roam_job.h \
 processing/jobs/update_sa_job.c processing/jobs/update_sa_job.h \
+processing/jobs/inactivity_job.c processing/jobs/inactivity_job.h \
 processing/scheduler.c processing/scheduler.h \
 processing/processor.c processing/processor.h  \
 sa/authenticators/authenticator.c sa/authenticators/authenticator.h \

src/charon/processing/jobs/inactivity_job.c

@@ -0,0 +1,150 @@
+/*
+ * Copyright (C) 2010 Martin Willi
+ * Hochschule fuer Technik Rapperswil
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+#include "inactivity_job.h"
+
+#include <daemon.h>
+
+typedef struct private_inactivity_job_t private_inactivity_job_t;
+
+/**
+ * Private data of an inactivity_job_t object.
+ */
+struct private_inactivity_job_t {
+
+	/**
+	 * Public inactivity_job_t interface.
+	 */
+	inactivity_job_t public;
+
+	/**
+	 * Reqid of CHILD_SA to check
+	 */
+	u_int32_t reqid;
+
+	/**
+	 * Inactivity timeout
+	 */
+	u_int32_t timeout;
+
+	/**
+	 * Close IKE_SA if last remaining CHILD inactive?
+	 */
+	bool close_ike;
+};
+
+METHOD(job_t, destroy, void,
+	private_inactivity_job_t *this)
+{
+	free(this);
+}
+
+METHOD(job_t, execute, void,
+	private_inactivity_job_t *this)
+{
+	ike_sa_t *ike_sa;
+	bool rescheduled = FALSE;
+
+	ike_sa = charon->ike_sa_manager->checkout_by_id(charon->ike_sa_manager,
+													this->reqid, TRUE);
+	if (ike_sa)
+	{
+		iterator_t *iterator;
+		child_sa_t *child_sa;
+		u_int32_t delete = 0;
+		protocol_id_t proto = 0;
+		int children = 0;
+		status_t status = SUCCESS;
+
+		iterator = ike_sa->create_child_sa_iterator(ike_sa);
+		while (iterator->iterate(iterator, (void**)&child_sa))
+		{
+			if (child_sa->get_reqid(child_sa) == this->reqid)
+			{
+				time_t in, out, diff;
+
+				child_sa->get_usestats(child_sa, TRUE, &in, NULL);
+				child_sa->get_usestats(child_sa, FALSE, &out, NULL);
+
+				diff = time_monotonic(NULL) - max(in, out);
+
+				if (diff >= this->timeout)
+				{
+					delete = child_sa->get_spi(child_sa, TRUE);
+					proto = child_sa->get_protocol(child_sa);
+				}
+				else
+				{
+					charon->scheduler->schedule_job(charon->scheduler,
+							&this->public.job_interface, this->timeout - diff);
+					rescheduled = TRUE;
+				}
+			}
+			children++;
+		}
+		iterator->destroy(iterator);
+
+		if (delete)
+		{
+			if (children == 1 && this->close_ike)
+			{
+				DBG1(DBG_JOB, "deleting IKE_SA after %d seconds "
+					 "of CHILD_SA inactivity", this->timeout);
+				status = ike_sa->delete(ike_sa);
+			}
+			else
+			{
+				DBG1(DBG_JOB, "deleting CHILD_SA after %d seconds "
+					 "of inactivity", this->timeout);
+				status = ike_sa->delete_child_sa(ike_sa, proto, delete);
+			}
+		}
+		if (status == DESTROY_ME)
+		{
+			charon->ike_sa_manager->checkin_and_destroy(charon->ike_sa_manager,
+														ike_sa);
+		}
+		else
+		{
+			charon->ike_sa_manager->checkin(charon->ike_sa_manager, ike_sa);
+		}
+	}
+	if (!rescheduled)
+	{
+		destroy(this);
+	}
+}
+
+/**
+ * See header
+ */
+inactivity_job_t *inactivity_job_create(u_int32_t reqid, u_int32_t timeout,
+										bool close_ike)
+{
+	private_inactivity_job_t *this;
+
+	INIT(this,
+		.public.job_interface = {
+			.execute = _execute,
+			.destroy = _destroy,
+		},
+		.reqid = reqid,
+		.timeout = timeout,
+		.close_ike = close_ike,
+	);
+
+	return &this->public;
+}
+

src/charon/processing/jobs/inactivity_job.h

@@ -0,0 +1,53 @@
+/*
+ * Copyright (C) 2010 Martin Willi
+ * Hochschule fuer Technik Rapperswil
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+/**
+ * @defgroup inactivity_job inactivity_job
+ * @{ @ingroup jobs
+ */
+
+#ifndef INACTIVITY_JOB_H_
+#define INACTIVITY_JOB_H_
+
+#include <library.h>
+#include <processing/jobs/job.h>
+
+typedef struct inactivity_job_t inactivity_job_t;
+
+/**
+ * Job checking for inactivity of CHILD_SA to close them.
+ *
+ * The inactivity job reschedules itself to check CHILD_SAs prediodically.
+ */
+struct inactivity_job_t {
+
+	/**
+	 * Implements job_t.
+	 */
+	job_t job_interface;
+};
+
+/**
+ * Create a inactivity_job instance.
+ *
+ * @param reqid		reqid of CHILD_SA to check for inactivity
+ * @param timeout	inactivity timeout in s
+ * @param close_ike	close IKE_SA if the last remaining CHILD_SA is inactive?
+ * @return			inactivity checking job
+ */
+inactivity_job_t *inactivity_job_create(u_int32_t reqid, u_int32_t timeout,
+										bool close_ike);
+
+#endif /** INACTIVITY_JOB_H_ @}*/

src/charon/sa/tasks/child_create.c

@@ -26,6 +26,7 @@
 #include <encoding/payloads/nonce_payload.h>
 #include <encoding/payloads/notify_payload.h>
 #include <processing/jobs/delete_ike_sa_job.h>
+#include <processing/jobs/inactivity_job.h>
 
 
 typedef struct private_child_create_t private_child_create_t;
@@ -247,6 +248,25 @@ static bool allocate_spi(private_child_create_t *this)
 	return FALSE;
 }
 
+/**
+ * Schedule inactivity timeout for CHILD_SA with reqid, if enabled
+ */
+static void schedule_inactivity_timeout(u_int32_t reqid)
+{
+	time_t timeout;
+	bool close_ike;
+
+	timeout = lib->settings->get_time(lib->settings,
+									  "charon.inactivity_timeout", 0);
+	if (timeout)
+	{
+		close_ike = lib->settings->get_bool(lib->settings,
+										"charon.inactivity_close_ike", FALSE);
+		charon->scheduler->schedule_job(charon->scheduler,
+			(job_t*)inactivity_job_create(reqid, timeout, close_ike), timeout);
+	}
+}
+
 /**
  * Install a CHILD_SA for usage, return value:
  * - FAILED: no acceptable proposal
@@ -516,6 +536,11 @@ static status_t select_and_install(private_child_create_t *this, bool no_dh)
 	this->child_sa->set_state(this->child_sa, CHILD_INSTALLED);
 	this->ike_sa->add_child_sa(this->ike_sa, this->child_sa);
 	this->established = TRUE;
+
+	if (!this->rekey)
+	{	/* a rekeyed SA uses the same reqid, no need for a new job */
+		schedule_inactivity_timeout(this->child_sa->get_reqid(this->child_sa));
+	}
 	return SUCCESS;
 }