stream-service: move CAP_CHOWN check from plugins to service constructor

A plugin service can be a TCP socket now, so it does not make much sense
to strictly check for CAP_CHOWN.

src/libcharon/plugins/duplicheck/duplicheck_plugin.c

@@ -98,12 +98,6 @@ plugin_t *duplicheck_plugin_create()
 		return NULL;
 	}
 
-	if (!lib->caps->check(lib->caps, CAP_CHOWN))
-	{	/* required to chown(2) notify socket */
-		DBG1(DBG_CFG, "duplicheck plugin requires CAP_CHOWN capability");
-		return NULL;
-	}
-
 	INIT(this,
 		.public = {
 			.plugin = {

src/libcharon/plugins/error_notify/error_notify_plugin.c

@@ -92,12 +92,6 @@ plugin_t *error_notify_plugin_create()
 {
 	private_error_notify_plugin_t *this;
 
-	if (!lib->caps->check(lib->caps, CAP_CHOWN))
-	{	/* required to chown(2) notify socket */
-		DBG1(DBG_CFG, "error-notify plugin requires CAP_CHOWN capability");
-		return NULL;
-	}
-
 	INIT(this,
 		.public = {
 			.plugin = {

src/libcharon/plugins/load_tester/load_tester_plugin.c

@@ -269,12 +269,6 @@ plugin_t *load_tester_plugin_create()
 		return NULL;
 	}
 
-	if (!lib->caps->check(lib->caps, CAP_CHOWN))
-	{	/* required to chown(2) control socket */
-		DBG1(DBG_CFG, "load-tester plugin requires CAP_CHOWN capability");
-		return NULL;
-	}
-
 	INIT(this,
 		.public = {
 			.plugin = {
@@ -304,4 +298,3 @@ plugin_t *load_tester_plugin_create()
 	}
 	return &this->public.plugin;
 }
-

src/libcharon/plugins/lookip/lookip_plugin.c

@@ -92,12 +92,6 @@ plugin_t *lookip_plugin_create()
 {
 	private_lookip_plugin_t *this;
 
-	if (!lib->caps->check(lib->caps, CAP_CHOWN))
-	{	/* required to chown(2) control socket */
-		DBG1(DBG_CFG, "lookip plugin requires CAP_CHOWN capability");
-		return NULL;
-	}
-
 	INIT(this,
 		.public = {
 			.plugin = {

src/libcharon/plugins/stroke/stroke_plugin.c

@@ -51,12 +51,13 @@ static bool register_stroke(private_stroke_plugin_t *this,
 	if (reg)
 	{
 		this->socket = stroke_socket_create();
+		return this->socket != NULL;
 	}
 	else
 	{
 		DESTROY_IF(this->socket);
+		return TRUE;
 	}
-	return TRUE;
 }
 
 METHOD(plugin_t, get_features, int,
@@ -91,12 +92,6 @@ plugin_t *stroke_plugin_create()
 {
 	private_stroke_plugin_t *this;
 
-	if (!lib->caps->check(lib->caps, CAP_CHOWN))
-	{	/* required to chown(2) stroke socket */
-		DBG1(DBG_CFG, "stroke plugin requires CAP_CHOWN capability");
-		return NULL;
-	}
-
 	INIT(this,
 		.public = {
 			.plugin = {
@@ -110,4 +105,3 @@ plugin_t *stroke_plugin_create()
 
 	return &this->public.plugin;
 }
-

src/libcharon/plugins/whitelist/whitelist_plugin.c

@@ -92,12 +92,6 @@ plugin_t *whitelist_plugin_create()
 {
 	private_whitelist_plugin_t *this;
 
-	if (!lib->caps->check(lib->caps, CAP_CHOWN))
-	{	/* required to chown(2) control socket */
-		DBG1(DBG_CFG, "whitelist plugin requires CAP_CHOWN capability");
-		return NULL;
-	}
-
 	INIT(this,
 		.public = {
 			.plugin = {

src/libstrongswan/networking/streams/stream_service.c

@@ -251,6 +251,11 @@ stream_service_t *stream_service_create_unix(char *uri, int backlog)
 		DBG1(DBG_NET, "invalid stream URI: '%s'", uri);
 		return NULL;
 	}
+	if (!lib->caps->check(lib->caps, CAP_CHOWN))
+	{	/* required to chown(2) service socket */
+		DBG1(DBG_NET, "socket '%s' requires CAP_CHOWN capability", uri);
+		return NULL;
+	}
 	fd = socket(AF_UNIX, SOCK_STREAM, 0);
 	if (fd == -1)
 	{