Bug 1688774 - Enable "Connection Settings" dialog to Accept file:// and npipe:// proxy

browser/components/preferences/dialogs/connection.js

@@ -128,7 +128,10 @@ var gConnectionsDialog = {
             .focus();
           event.preventDefault();
           return;
-        } else if (!Services.io.isValidHostname(proxyPref.value)) {
+        } else if (
+          !Services.io.isValidHostname(proxyPref.value) &&
+          !(prefName === "socks" && (proxyPref.value.startsWith("file://") || proxyPref.value.startsWith("npipe://")))
+        ) {
           document
             .getElementById("networkProxy" + prefName.toUpperCase())
             .focus();

browser/components/preferences/tests/networking/browser_connection_valid_hostname.js

@@ -53,3 +53,77 @@ add_task(async function test_valid_hostname() {
 
   gBrowser.removeCurrentTab();
 });
+
+add_task(async function test_socks_file_uri() {
+  await openPreferencesViaOpenPreferencesAPI("general", { leaveOpen: true });
+  const connectionURL =
+    "chrome://browser/content/preferences/dialogs/connection.xhtml";
+  let dialog = await openAndLoadSubDialog(connectionURL);
+  let dialogElement = dialog.document.getElementById("ConnectionsDialog");
+
+  let oldNetworkProxyType = Services.prefs.getIntPref("network.proxy.type");
+  let oldSocksPort = Services.prefs.getIntPref("network.proxy.socks_port");
+  registerCleanupFunction(function () {
+    Services.prefs.setIntPref("network.proxy.type", oldNetworkProxyType);
+    Services.prefs.setIntPref("network.proxy.socks_port", oldSocksPort);
+    Services.prefs.clearUserPref("network.proxy.share_proxy_settings");
+    for (let proxyType of ["http", "ssl", "socks"]) {
+      Services.prefs.clearUserPref("network.proxy." + proxyType);
+      Services.prefs.clearUserPref("network.proxy." + proxyType + "_port");
+      if (proxyType == "http") {
+        continue;
+      }
+      Services.prefs.clearUserPref("network.proxy.backup." + proxyType);
+      Services.prefs.clearUserPref(
+        "network.proxy.backup." + proxyType + "_port"
+      );
+    }
+  });
+
+  let proxyType = dialog.Preferences.get("network.proxy.type");
+  let socksPref = dialog.Preferences.get("network.proxy.socks");
+  let socksPortPref = dialog.Preferences.get("network.proxy.socks_port");
+  proxyType.value = 1;
+  socksPortPref.value = 1234;
+
+  // file:// URIs should be accepted for SOCKS
+  socksPref.value = "file:///var/run/socks5.sock";
+  let beforeAcceptCalled = BrowserTestUtils.waitForEvent(
+    dialogElement,
+    "beforeaccept"
+  );
+  dialogElement.acceptDialog();
+  let event = await beforeAcceptCalled;
+  Assert.ok(
+    !event.defaultPrevented,
+    "The dialog was accepted with file:// SOCKS path"
+  );
+
+  // npipe:// URIs should also be accepted for SOCKS (Windows named pipes)
+  socksPref.value = "npipe:///./pipe/socks";
+  beforeAcceptCalled = BrowserTestUtils.waitForEvent(
+    dialogElement,
+    "beforeaccept"
+  );
+  dialogElement.acceptDialog();
+  event = await beforeAcceptCalled;
+  Assert.ok(
+    !event.defaultPrevented,
+    "The dialog was accepted with npipe:// SOCKS path"
+  );
+
+  // Regular hostnames should still work for SOCKS
+  socksPref.value = "localhost";
+  beforeAcceptCalled = BrowserTestUtils.waitForEvent(
+    dialogElement,
+    "beforeaccept"
+  );
+  dialogElement.acceptDialog();
+  event = await beforeAcceptCalled;
+  Assert.ok(
+    !event.defaultPrevented,
+    "The dialog was accepted with regular SOCKS hostname"
+  );
+
+  gBrowser.removeCurrentTab();
+});