Add bind_address option (#349)

Add option to set the IP address the master server binds its HTTP and
HTTPS ports to.

docs/configuration.md

@@ -32,6 +32,17 @@ of this and master.http_port needs to be set to a port.
 Defaults to 8443.
 
 
+### master.bind_address
+
+IP address to bind the HTTP and HTTPS ports on.  Useful to limit which
+interface to accept connections from.  If set to null the unspecified
+IPv6 address will be used, which on most systems means it will also
+listen on the unspecified IPv4 address and accept connections from all
+interfaces.
+
+Defaults to null.
+
+
 ### master.external_address
 
 External address the master server is accessible on.  Currently only

packages/lib/config/definitions.js

@@ -33,6 +33,13 @@ MasterGroup.define({
 	optional: true,
 	initial_value: 8443,
 });
+MasterGroup.define({
+	name: "bind_address",
+	title: "Bind Address",
+	description: "IP address to bind the HTTP and HTTPS ports on.",
+	type: "string",
+	optional: true,
+});
 MasterGroup.define({
 	name: "external_address",
 	title: "External Address",

packages/master/master.js

@@ -1943,6 +1943,7 @@ async function startServer() {
 	// Make sure we're actually going to listen on a port
 	let httpPort = masterConfig.get("master.http_port");
 	let httpsPort = masterConfig.get("master.https_port");
+	let bindAddress = masterConfig.get("master.bind_address") || "";
 	if (!httpPort && !httpsPort) {
 		logger.fatal("Error: at least one of http_port and https_port must be configured");
 		process.exit(1);
@@ -1980,7 +1981,7 @@ async function startServer() {
 	// Only start listening for connections after all plugins have loaded
 	if (httpPort) {
 		httpServer = new (require("http").Server)(app);
-		await listen(httpServer, httpPort);
+		await listen(httpServer, httpPort, bindAddress);
 		logger.info(`Listening for HTTP on port ${httpServer.address().port}`);
 	}
 
@@ -2000,7 +2001,7 @@ async function startServer() {
 			key: privateKey,
 			cert: certificate,
 		}, app);
-		await listen(httpsServer, httpsPort);
+		await listen(httpsServer, httpsPort, bindAddress);
 		logger.info(`Listening for HTTPS on port ${httpsServer.address().port}`);
 	}
 }