Added navigator protection

lib/main.js

@@ -140,6 +140,9 @@
 	message("Initialize data-URL workaround.");
 	require("./dataUrls").init();
 	
+	message("Initialize navigator HTTP header protection.");
+	require("./navigator").init();
+	
 	browser.runtime.onInstalled.addListener(function(details){
 		function openOptions(reason){
 			if (

lib/modifiedAPI.js

@@ -540,4 +540,5 @@
 	appendModified(require("./modifiedHistoryAPI"));
 	appendModified(require("./modifiedWindowAPI"));
 	appendModified(modifiedDOMRectAPI);
+	appendModified(require("./modifiedNavigatorAPI"));
 }());

lib/modifiedNavigatorAPI.js

@@ -0,0 +1,52 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+(function(){
+	"use strict";
+	
+	var scope;
+	if ((typeof exports) !== "undefined"){
+		scope = exports;
+	}
+	else {
+		scope = require.register("./modifiedNavigatorAPI", {});
+	}
+	
+	const {checkerWrapper} = require("./modifiedAPIFunctions");
+	const navigator = require("./navigator");
+	
+	scope.changedGetters = navigator.allProperties.map(function(property){
+		return {
+			objectGetters: [function(window){return window.Navigator && window.Navigator.prototype;}],
+			name: property,
+			getterGenerator: function(checker){
+				const temp = {
+					get [property](){
+						return checkerWrapper(checker, this, arguments, function(args, check){
+							const {prefs, notify, window, original} = check;
+							const originalValue = original.apply(this, window.Array.from(args));
+							const returnValue = navigator.getNavigatorValue(property);
+							if (originalValue !== returnValue){
+								notify("fakedNavigatorReadout");
+							}
+							return returnValue;
+						});
+					}
+				};
+				return Object.getOwnPropertyDescriptor(temp, property).get;
+			}
+		};
+	});
+	
+	function getStatus(obj, status, prefs){
+		status = Object.create(status);
+		status.active = prefs("protectNavigator", status.url);
+		return status;
+	}
+	
+	scope.changedGetters.forEach(function(changedGetter){
+		changedGetter.type = "readout";
+		changedGetter.getStatus = getStatus;
+		changedGetter.api = "navigator";
+	});
+}());

lib/navigator.js

@@ -0,0 +1,116 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+(function(){
+	"use strict";
+	
+	var scope;
+	if ((typeof exports) !== "undefined"){
+		scope = exports;
+	}
+	else {
+		scope = require.register("./navigator", {});
+	}
+	
+	const settings = require("./settings");
+	const logging = require("./logging");
+	
+	scope.allProperties = [
+		"appCodeName", "appName",
+		"appVersion", "buildID", "oscpu", "platform",
+		"product",
+		"productSub", "userAgent", "vendor", "vendorSub"];
+	const original = {};
+	scope.allProperties.forEach(function(property){
+		original[property] = window.navigator[property];
+	});
+	original["real Firefox version"] = window.navigator.userAgent.replace(/^.+Firefox\//, "");
+	
+	let changedValues = {};
+	
+	settings.onloaded(function(){
+		changedValues = settings.navigatorDetails;
+	});
+	settings.on("navigatorDetails", function({newValue}){
+		changedValues = newValue;
+	});
+	
+	
+	function getValue(name, stack = []){
+		if (stack.indexOf(name) !== -1){
+			return "[ERROR: loop in property definition]";
+		}
+		stack.push(name);
+		
+		switch (name){
+			case "original value":
+				return original[stack[stack.length - 2]];
+			case "random":
+				return String.fromCharCode(Math.floor(65 + 85 * Math.random()));
+			default:
+				if (changedValues.hasOwnProperty(name)){
+					return parseString(changedValues[name], stack.slice());
+				}
+				else {
+					return original[name];
+				}
+		}
+	}
+	function parseString(string, stack){
+		return string.replace(/{([a-z[\]_. -]*)}/ig, function(m, name){
+			return getValue(name, stack.slice());
+		});
+	}
+	
+	scope.getNavigatorValue = function getNavigatorValue(name){
+		return getValue(name);
+	};
+	
+	function changeHTTPHeader(details){
+		if (
+			settings.protectNavigator &&
+			(
+				!settings.protectedAPIFeatures.hasOwnProperty("userAgent") ||
+				settings.protectedAPIFeatures.userAgent
+			)
+		){
+			for (var header of details.requestHeaders){
+				if (header.name.toLowerCase() === "user-agent"){
+					header.value = getValue("userAgent");
+				}
+			}
+		}
+		return details;
+	}
+	
+	scope.registerHeaderChange = function(){
+		logging.message("Register HTTP header modification for navigator protection.");
+		if (!browser.webRequest.onBeforeSendHeaders.hasListener(changeHTTPHeader)){
+			browser.webRequest.onBeforeSendHeaders.addListener(
+				changeHTTPHeader,
+				{
+					urls: ["<all_urls>"],
+				},
+				["blocking", "requestHeaders"]);
+		}
+	};
+	scope.unregisterHeaderChange = function(){
+		logging.message("Removing header modification for navigator protection.");
+		browser.webRequest.onBeforeSendHeaders.removeListener(changeHTTPHeader);
+	};
+	scope.init = function (){
+		settings.onloaded(function(){
+			if (!settings.protectNavigator){
+				scope.unregisterHeaderChange();
+			}
+		});
+		settings.on("protectNavigator", function({newValue}){
+			if (newValue){
+				scope.registerHeaderChange();
+			}
+			else {
+				scope.unregisterHeaderChange();
+			}
+		});
+	};
+}());

lib/settingDefinitions.js

@@ -117,6 +117,18 @@
 				"intersectionRect",
 				"boundingClientRect",
 				"rootBounds",
+				{name: "Navigator-API", level: 1},
+				"appCodeName",
+				"appName",
+				"appVersion",
+				"buildID",
+				"oscpu",
+				"platform",
+				"product",
+				"productSub",
+				"userAgent",
+				"vendor",
+				"vendorSub"
 			],
 			defaultKeyValue: true
 		},
@@ -222,6 +234,7 @@
 				"history",
 				"window",
 				"domRect",
+				"navigator",
 			],
 			defaultKeyValue: false
 		},
@@ -293,6 +306,14 @@
 			name: "blockDataURLs",
 			defaultValue: true
 		},
+		{
+			name: "protectNavigator",
+			defaultValue: false
+		},
+		{
+			name: "navigatorDetails",
+			defaultValue: {},
+		},
 		{
 			name: "displayAdvancedSettings",
 			defaultValue: false