Bug 1560703 - Make sure creating an FTP channel throws if FTP is disabled r=michal

Previously we would throw in nsFtpProtocolHandler::NewURI. Since that doesn't exist anymore, and creating FTP URLs always works, we need to make sure creating the FTP channel doesn't work anymore.

Differential Revision: https://phabricator.services.mozilla.com/D35642

--HG--
extra : moz-landing-system : lando

netwerk/protocol/ftp/nsFtpProtocolHandler.cpp

@@ -151,6 +151,10 @@ nsFtpProtocolHandler::NewProxiedChannel(nsIURI* uri, nsIProxyInfo* proxyInfo,
                                         nsIURI* proxyURI,
                                         nsILoadInfo* aLoadInfo,
                                         nsIChannel** result) {
+  if (!mEnabled) {
+    return NS_ERROR_UNKNOWN_PROTOCOL;
+  }
+
   NS_ENSURE_ARG_POINTER(uri);
   RefPtr<nsBaseChannel> channel;
   if (IsNeckoChild())

netwerk/test/unit/test_disabled_ftp.js

@@ -0,0 +1,12 @@
+registerCleanupFunction(function() {
+  Services.prefs.clearUserPref("network.ftp.enabled");
+});
+
+add_task(async function ftp_disabled() {
+  Services.prefs.setBoolPref("network.ftp.enabled", false);
+
+  let chan = null;
+  Assert.throws(() => { chan = NetUtil.newChannel({uri: "ftp://ftp.de.debian.org/", loadUsingSystemPrincipal: true})
+                .QueryInterface(Ci.nsIHttpChannel); },
+                /NS_ERROR_UNKNOWN_PROTOCOL/, "creating the FTP channel must throw");
+});

netwerk/test/unit/xpcshell.ini

@@ -456,3 +456,5 @@ run-sequentially = one http2 node proxy is used for all tests, this test is usin
 # so far has to be disabled until we update nodejs to at least 8.4+, then keep off on android (os == "android")
 skip-if = true
 [test_head_request_no_response_body.js]
+[test_disabled_ftp.js]
+