bus: Add ike_reestablish_pre hook, called before DNS resolution

The old hook is renamed to ike_reestablish_post and is now also called
when the initiation of the new IKE_SA failed.

src/frontends/android/jni/libandroidbridge/backend/android_service.c

@@ -445,10 +445,11 @@ METHOD(listener_t, ike_rekey, bool,
 	return TRUE;
 }
 
-METHOD(listener_t, ike_reestablish, bool,
-	private_android_service_t *this, ike_sa_t *old, ike_sa_t *new)
+METHOD(listener_t, ike_reestablish_post, bool,
+	private_android_service_t *this, ike_sa_t *old, ike_sa_t *new,
+	bool initiated)
 {
-	if (this->ike_sa == old)
+	if (this->ike_sa == old && initiated)
 	{
 		this->ike_sa = new;
 		/* re-register hook to detect initiation failures */
@@ -655,7 +656,7 @@ android_service_t *android_service_create(android_creds_t *creds, char *type,
 		.public = {
 			.listener = {
 				.ike_rekey = _ike_rekey,
-				.ike_reestablish = _ike_reestablish,
+				.ike_reestablish_post = _ike_reestablish_post,
 				.ike_updown = _ike_updown,
 				.child_updown = _child_updown,
 				.alert = _alert,

src/libcharon/bus/bus.c

@@ -755,7 +755,7 @@ METHOD(bus_t, ike_rekey, void,
 	this->mutex->unlock(this->mutex);
 }
 
-METHOD(bus_t, ike_reestablish, void,
+METHOD(bus_t, ike_reestablish_pre, void,
 	private_bus_t *this, ike_sa_t *old, ike_sa_t *new)
 {
 	enumerator_t *enumerator;
@@ -766,12 +766,40 @@ METHOD(bus_t, ike_reestablish, void,
 	enumerator = this->listeners->create_enumerator(this->listeners);
 	while (enumerator->enumerate(enumerator, &entry))
 	{
-		if (entry->calling || !entry->listener->ike_reestablish)
+		if (entry->calling || !entry->listener->ike_reestablish_pre)
 		{
 			continue;
 		}
 		entry->calling++;
-		keep = entry->listener->ike_reestablish(entry->listener, old, new);
+		keep = entry->listener->ike_reestablish_pre(entry->listener, old, new);
+		entry->calling--;
+		if (!keep)
+		{
+			unregister_listener(this, entry, enumerator);
+		}
+	}
+	enumerator->destroy(enumerator);
+	this->mutex->unlock(this->mutex);
+}
+
+METHOD(bus_t, ike_reestablish_post, void,
+	private_bus_t *this, ike_sa_t *old, ike_sa_t *new, bool initiated)
+{
+	enumerator_t *enumerator;
+	entry_t *entry;
+	bool keep;
+
+	this->mutex->lock(this->mutex);
+	enumerator = this->listeners->create_enumerator(this->listeners);
+	while (enumerator->enumerate(enumerator, &entry))
+	{
+		if (entry->calling || !entry->listener->ike_reestablish_post)
+		{
+			continue;
+		}
+		entry->calling++;
+		keep = entry->listener->ike_reestablish_post(entry->listener, old, new,
+													 initiated);
 		entry->calling--;
 		if (!keep)
 		{
@@ -978,7 +1006,8 @@ bus_t *bus_create()
 			.child_keys = _child_keys,
 			.ike_updown = _ike_updown,
 			.ike_rekey = _ike_rekey,
-			.ike_reestablish = _ike_reestablish,
+			.ike_reestablish_pre = _ike_reestablish_pre,
+			.ike_reestablish_post = _ike_reestablish_post,
 			.child_updown = _child_updown,
 			.child_rekey = _child_rekey,
 			.authorize = _authorize,

src/libcharon/bus/bus.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2012 Tobias Brunner
+ * Copyright (C) 2012-2014 Tobias Brunner
  * Copyright (C) 2006-2009 Martin Willi
  * Hochschule fuer Technik Rapperswil
  *
@@ -380,12 +380,23 @@ struct bus_t {
 	void (*ike_rekey)(bus_t *this, ike_sa_t *old, ike_sa_t *new);
 
 	/**
-	 * IKE_SA reestablishing hook.
+	 * IKE_SA reestablishing hook (before resolving hosts).
 	 *
 	 * @param old		reestablished and obsolete IKE_SA
 	 * @param new		new IKE_SA replacing old
 	 */
-	void (*ike_reestablish)(bus_t *this, ike_sa_t *old, ike_sa_t *new);
+	void (*ike_reestablish_pre)(bus_t *this, ike_sa_t *old, ike_sa_t *new);
+
+	/**
+	 * IKE_SA reestablishing hook (after configuring and initiating the new
+	 * IKE_SA).
+	 *
+	 * @param old		reestablished and obsolete IKE_SA
+	 * @param new		new IKE_SA replacing old
+	 * @param initiated	TRUE if initiated successfully, FALSE otherwise
+	 */
+	void (*ike_reestablish_post)(bus_t *this, ike_sa_t *old, ike_sa_t *new,
+								 bool initiated);
 
 	/**
 	 * CHILD_SA up/down hook.

src/libcharon/bus/listeners/listener.h

@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2011-2014 Tobias Brunner
  * Copyright (C) 2009 Martin Willi
  * Hochschule fuer Technik Rapperswil
  *
@@ -129,14 +130,29 @@ struct listener_t {
 	/**
 	 * Hook called when an initiator reestablishes an IKE_SA.
 	 *
-	 * This is invoked right before the new IKE_SA is checked in after
-	 * initiating it.  It is not invoked on the responder.
+	 * This is invoked right after creating the new IKE_SA and setting the
+	 * peer_cfg (and the old hosts), but before resolving the hosts anew.
+	 * It is not invoked on the responder.
 	 *
 	 * @param old		IKE_SA getting reestablished (is destroyed)
 	 * @param new		new IKE_SA replacing old (gets established)
 	 * @return			TRUE to stay registered, FALSE to unregister
 	 */
-	bool (*ike_reestablish)(listener_t *this, ike_sa_t *old, ike_sa_t *new);
+	bool (*ike_reestablish_pre)(listener_t *this, ike_sa_t *old, ike_sa_t *new);
+
+	/**
+	 * Hook called when an initiator reestablishes an IKE_SA.
+	 *
+	 * This is invoked right before the new IKE_SA is checked in after
+	 * initiating it.  It is not invoked on the responder.
+	 *
+	 * @param old		IKE_SA getting reestablished (is destroyed)
+	 * @param new		new IKE_SA replacing old (gets established)
+	 * @param initiated TRUE if initiation was successful, FALSE otherwise
+	 * @return			TRUE to stay registered, FALSE to unregister
+	 */
+	bool (*ike_reestablish_post)(listener_t *this, ike_sa_t *old,
+								 ike_sa_t *new, bool initiated);
 
 	/**
 	 * Hook called when a CHILD_SA gets up or down.

src/libcharon/sa/ike_sa.c

@@ -1650,6 +1650,7 @@ METHOD(ike_sa_t, reestablish, status_t,
 	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);
 	/* resolve hosts but use the old addresses above as fallback */
 	resolve_hosts((private_ike_sa_t*)new);
 	/* if we already have a virtual IP, we reuse it */
@@ -1734,12 +1735,15 @@ METHOD(ike_sa_t, reestablish, status_t,
 
 	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(charon->bus, &this->public, new);
+		charon->bus->ike_reestablish_post(charon->bus, &this->public, new,
+										  TRUE);
 		charon->ike_sa_manager->checkin(charon->ike_sa_manager, new);
 		status = SUCCESS;
 	}